Intranet
Acces
Contact
Accès direct
Unités de recherche
Bienvenue
Spectrométrie de masse
Publications
2024
Hoffmann Anne, Lorenz Christian, Fallmann Jörg, Wolff Philippe, Lechner Antony, Betat Heike, Mörl Mario, Stadler Peter F
Temperature-Dependent tRNA Modifications in Bacillales Article de journal
Dans: Int J Mol Sci, vol. 25, no. 16, 2024, ISSN: 1422-0067.
Résumé | Liens | BibTeX | Étiquettes: ARN-MS, Unité ARN
@article{pmid39201508,
title = {Temperature-Dependent tRNA Modifications in Bacillales},
author = {Anne Hoffmann and Christian Lorenz and Jörg Fallmann and Philippe Wolff and Antony Lechner and Heike Betat and Mario Mörl and Peter F Stadler},
doi = {10.3390/ijms25168823},
issn = {1422-0067},
year = {2024},
date = {2024-08-01},
urldate = {2024-08-01},
journal = {Int J Mol Sci},
volume = {25},
number = {16},
abstract = {Transfer RNA (tRNA) modifications are essential for the temperature adaptation of thermophilic and psychrophilic organisms as they control the rigidity and flexibility of transcripts. To further understand how specific tRNA modifications are adjusted to maintain functionality in response to temperature fluctuations, we investigated whether tRNA modifications represent an adaptation of bacteria to different growth temperatures (minimal, optimal, and maximal), focusing on closely related psychrophilic ( and ), mesophilic (), and thermophilic () Bacillales. Utilizing an RNA sequencing approach combined with chemical pre-treatment of tRNA samples, we systematically profiled dihydrouridine (D), 4-thiouridine (sU), 7-methyl-guanosine (mG), and pseudouridine (Ψ) modifications at single-nucleotide resolution. Despite their close relationship, each bacterium exhibited a unique tRNA modification profile. Our findings revealed increased tRNA modifications in the thermophilic bacterium at its optimal growth temperature, particularly showing elevated levels of sU8 and Ψ55 modifications compared to non-thermophilic bacteria, indicating a temperature-dependent regulation that may contribute to thermotolerance. Furthermore, we observed higher levels of D modifications in psychrophilic and mesophilic bacteria, indicating an adaptive strategy for cold environments by enhancing local flexibility in tRNAs. Our method demonstrated high effectiveness in identifying tRNA modifications compared to an established tool, highlighting its potential for precise tRNA profiling studies.},
keywords = {ARN-MS, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
Transfer RNA (tRNA) modifications are essential for the temperature adaptation of thermophilic and psychrophilic organisms as they control the rigidity and flexibility of transcripts. To further understand how specific tRNA modifications are adjusted to maintain functionality in response to temperature fluctuations, we investigated whether tRNA modifications represent an adaptation of bacteria to different growth temperatures (minimal, optimal, and maximal), focusing on closely related psychrophilic ( and ), mesophilic (), and thermophilic () Bacillales. Utilizing an RNA sequencing approach combined with chemical pre-treatment of tRNA samples, we systematically profiled dihydrouridine (D), 4-thiouridine (sU), 7-methyl-guanosine (mG), and pseudouridine (Ψ) modifications at single-nucleotide resolution. Despite their close relationship, each bacterium exhibited a unique tRNA modification profile. Our findings revealed increased tRNA modifications in the thermophilic bacterium at its optimal growth temperature, particularly showing elevated levels of sU8 and Ψ55 modifications compared to non-thermophilic bacteria, indicating a temperature-dependent regulation that may contribute to thermotolerance. Furthermore, we observed higher levels of D modifications in psychrophilic and mesophilic bacteria, indicating an adaptive strategy for cold environments by enhancing local flexibility in tRNAs. Our method demonstrated high effectiveness in identifying tRNA modifications compared to an established tool, highlighting its potential for precise tRNA profiling studies.
Pitolli Martina, Cela Marta, Kapps Delphine, Chicher Johana, Despons Laurence, Frugier Magali
Comparative proteomics uncovers low asparagine content in Plasmodium tRip-KO proteins Article de journal
Dans: IUBMB Life, 2024, ISSN: 1521-6551.
Résumé | Liens | BibTeX | Étiquettes: PPSE, RYCKELYNCK, Unité ARN
@article{pmid38963319,
title = {Comparative proteomics uncovers low asparagine content in Plasmodium tRip-KO proteins},
author = {Martina Pitolli and Marta Cela and Delphine Kapps and Johana Chicher and Laurence Despons and Magali Frugier},
doi = {10.1002/iub.2891},
issn = {1521-6551},
year = {2024},
date = {2024-07-01},
urldate = {2024-07-01},
journal = {IUBMB Life},
abstract = {tRNAs are not only essential for decoding the genetic code, but their abundance also has a strong impact on the rate of protein production, folding, and on the stability of the translated messenger RNAs. Plasmodium expresses a unique surface protein called tRip, involved in the import of exogenous tRNAs into the parasite. Comparative proteomic analysis of the blood stage of wild-type and tRip-KO variant of P. berghei parasites revealed that downregulated proteins in the mutant parasite are distinguished by a bias in their asparagine content. Furthermore, the demonstration of the possibility of charging host tRNAs with Plasmodium aminoacyl-tRNA synthetases led us to propose that imported host tRNAs participate in parasite protein synthesis. These results also suggest a novel mechanism of translational control in which import of host tRNAs emerge as regulators of gene expression in the Plasmodium developmental cycle and pathogenesis, by enabling the synthesis of asparagine-rich regulatory proteins that efficiently and selectively control the parasite infectivity.},
keywords = {PPSE, RYCKELYNCK, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
tRNAs are not only essential for decoding the genetic code, but their abundance also has a strong impact on the rate of protein production, folding, and on the stability of the translated messenger RNAs. Plasmodium expresses a unique surface protein called tRip, involved in the import of exogenous tRNAs into the parasite. Comparative proteomic analysis of the blood stage of wild-type and tRip-KO variant of P. berghei parasites revealed that downregulated proteins in the mutant parasite are distinguished by a bias in their asparagine content. Furthermore, the demonstration of the possibility of charging host tRNAs with Plasmodium aminoacyl-tRNA synthetases led us to propose that imported host tRNAs participate in parasite protein synthesis. These results also suggest a novel mechanism of translational control in which import of host tRNAs emerge as regulators of gene expression in the Plasmodium developmental cycle and pathogenesis, by enabling the synthesis of asparagine-rich regulatory proteins that efficiently and selectively control the parasite infectivity.
Holvec Samuel, Barchet Charles, Lechner Antony, Fréchin Léo, Silva S Nimali T De, Hazemann Isabelle, Wolff Philippe, von Loeffelholz Ottilie, Klaholz Bruno P
The structure of the human 80S ribosome at 1.9 Å resolution reveals the molecular role of chemical modifications and ions in RNA Article de journal
Dans: Nat Struct Mol Biol, 2024, ISSN: 1545-9985.
Résumé | Liens | BibTeX | Étiquettes: ARN-MS, Unité ARN
@article{pmid38844527,
title = {The structure of the human 80S ribosome at 1.9 Å resolution reveals the molecular role of chemical modifications and ions in RNA},
author = {Samuel Holvec and Charles Barchet and Antony Lechner and Léo Fréchin and S Nimali T De Silva and Isabelle Hazemann and Philippe Wolff and Ottilie von Loeffelholz and Bruno P Klaholz},
doi = {10.1038/s41594-024-01274-x},
issn = {1545-9985},
year = {2024},
date = {2024-06-01},
urldate = {2024-06-01},
journal = {Nat Struct Mol Biol},
abstract = {The ribosomal RNA of the human protein synthesis machinery comprises numerous chemical modifications that are introduced during ribosome biogenesis. Here we present the 1.9 Å resolution cryo electron microscopy structure of the 80S human ribosome resolving numerous new ribosomal RNA modifications and functionally important ions such as Zn, K and Mg, including their associated individual water molecules. The 2'-O-methylation, pseudo-uridine and base modifications were confirmed by mass spectrometry, resulting in a complete investigation of the >230 sites, many of which could not be addressed previously. They choreograph key interactions within the RNA and at the interface with proteins, including at the ribosomal subunit interfaces of the fully assembled 80S ribosome. Uridine isomerization turns out to be a key mechanism for U-A base pair stabilization in RNA in general. The structural environment of chemical modifications and ions is primordial for the RNA architecture of the mature human ribosome, hence providing a structural framework to address their role in healthy states and in human diseases.},
keywords = {ARN-MS, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
The ribosomal RNA of the human protein synthesis machinery comprises numerous chemical modifications that are introduced during ribosome biogenesis. Here we present the 1.9 Å resolution cryo electron microscopy structure of the 80S human ribosome resolving numerous new ribosomal RNA modifications and functionally important ions such as Zn, K and Mg, including their associated individual water molecules. The 2'-O-methylation, pseudo-uridine and base modifications were confirmed by mass spectrometry, resulting in a complete investigation of the >230 sites, many of which could not be addressed previously. They choreograph key interactions within the RNA and at the interface with proteins, including at the ribosomal subunit interfaces of the fully assembled 80S ribosome. Uridine isomerization turns out to be a key mechanism for U-A base pair stabilization in RNA in general. The structural environment of chemical modifications and ions is primordial for the RNA architecture of the mature human ribosome, hence providing a structural framework to address their role in healthy states and in human diseases.
Messmer Mélanie, Pierson Louison, Pasquier Charline, Djordjevic Nikola, Chicher Johana, Hammann Philippe, Pfeffer Sébastien, Girardi Erika
DEAD box RNA helicase 5 is a new pro-viral host factor for Sindbis virus infection Article de journal
Dans: Virol J, vol. 21, no. 1, p. 76, 2024, ISSN: 1743-422X.
Résumé | Liens | BibTeX | Étiquettes: PFEFFER, PPSE, Unité ARN
@article{pmid38553727,
title = {DEAD box RNA helicase 5 is a new pro-viral host factor for Sindbis virus infection},
author = {Mélanie Messmer and Louison Pierson and Charline Pasquier and Nikola Djordjevic and Johana Chicher and Philippe Hammann and Sébastien Pfeffer and Erika Girardi},
doi = {10.1186/s12985-024-02349-3},
issn = {1743-422X},
year = {2024},
date = {2024-03-01},
urldate = {2024-03-01},
journal = {Virol J},
volume = {21},
number = {1},
pages = {76},
abstract = {BACKGROUND: RNA helicases are emerging as key factors regulating host-virus interactions. The DEAD-box ATP-dependent RNA helicase DDX5, which plays an important role in many aspects of cellular RNA biology, was also found to either promote or inhibit viral replication upon infection with several RNA viruses. Here, our aim is to examine the impact of DDX5 on Sindbis virus (SINV) infection.nnMETHODS: We analysed the interaction between DDX5 and the viral RNA using imaging and RNA-immunoprecipitation approaches. The interactome of DDX5 in mock- and SINV-infected cells was determined by mass spectrometry. We validated the interaction between DDX17 and the viral capsid by co- immunoprecipitation in the presence or absence of an RNase treatment. We determined the subcellular localization of DDX5, its cofactor DDX17 and the viral capsid protein by co-immunofluorescence. Finally, we investigated the impact of DDX5 depletion and overexpression on SINV infection at the viral protein, RNA and infectious particle accumulation level. The contribution of DDX17 was also tested by knockdown experiments.nnRESULTS: In this study we demonstrate that DDX5 interacts with the SINV RNA during infection. Furthermore, the proteomic analysis of the DDX5 interactome in mock and SINV-infected HCT116 cells identified new cellular and viral partners and confirmed the interaction between DDX5 and DDX17. Both DDX5 and DDX17 re-localize from the nucleus to the cytoplasm upon SINV infection and interact with the viral capsid protein. We also show that DDX5 depletion negatively impacts the viral replication cycle, while its overexpression has a pro-viral effect. Finally, we observed that DDX17 depletion reduces SINV infection, an effect which is even more pronounced in a DDX5-depleted background, suggesting a synergistic pro-viral effect of the DDX5 and DDX17 proteins on SINV.nnCONCLUSIONS: These results not only shed light on DDX5 as a novel and important host factor to the SINV life cycle, but also expand our understanding of the roles played by DDX5 and DDX17 as regulators of viral infections.},
keywords = {PFEFFER, PPSE, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
BACKGROUND: RNA helicases are emerging as key factors regulating host-virus interactions. The DEAD-box ATP-dependent RNA helicase DDX5, which plays an important role in many aspects of cellular RNA biology, was also found to either promote or inhibit viral replication upon infection with several RNA viruses. Here, our aim is to examine the impact of DDX5 on Sindbis virus (SINV) infection.nnMETHODS: We analysed the interaction between DDX5 and the viral RNA using imaging and RNA-immunoprecipitation approaches. The interactome of DDX5 in mock- and SINV-infected cells was determined by mass spectrometry. We validated the interaction between DDX17 and the viral capsid by co- immunoprecipitation in the presence or absence of an RNase treatment. We determined the subcellular localization of DDX5, its cofactor DDX17 and the viral capsid protein by co-immunofluorescence. Finally, we investigated the impact of DDX5 depletion and overexpression on SINV infection at the viral protein, RNA and infectious particle accumulation level. The contribution of DDX17 was also tested by knockdown experiments.nnRESULTS: In this study we demonstrate that DDX5 interacts with the SINV RNA during infection. Furthermore, the proteomic analysis of the DDX5 interactome in mock and SINV-infected HCT116 cells identified new cellular and viral partners and confirmed the interaction between DDX5 and DDX17. Both DDX5 and DDX17 re-localize from the nucleus to the cytoplasm upon SINV infection and interact with the viral capsid protein. We also show that DDX5 depletion negatively impacts the viral replication cycle, while its overexpression has a pro-viral effect. Finally, we observed that DDX17 depletion reduces SINV infection, an effect which is even more pronounced in a DDX5-depleted background, suggesting a synergistic pro-viral effect of the DDX5 and DDX17 proteins on SINV.nnCONCLUSIONS: These results not only shed light on DDX5 as a novel and important host factor to the SINV life cycle, but also expand our understanding of the roles played by DDX5 and DDX17 as regulators of viral infections.
D'Agostino Mattia, Simonetti Angelita, Motta Stefano, Wolff Philippe, Romagnoli Alice, Piccinini Astra, Spinozzi Francesco, Marino Daniele Di, Teana Anna La, Ennifar Eric
Crystal structure of archaeal IF5A-DHS complex reveals insights into the hypusination mechanism Article de journal
Dans: Structure, 2024, ISSN: 1878-4186.
Résumé | Liens | BibTeX | Étiquettes: ARN-MS, ENNIFAR, Unité ARN
@article{pmid38582076,
title = {Crystal structure of archaeal IF5A-DHS complex reveals insights into the hypusination mechanism},
author = {Mattia D'Agostino and Angelita Simonetti and Stefano Motta and Philippe Wolff and Alice Romagnoli and Astra Piccinini and Francesco Spinozzi and Daniele Di Marino and Anna La Teana and Eric Ennifar},
doi = {10.1016/j.str.2024.03.008},
issn = {1878-4186},
year = {2024},
date = {2024-03-01},
urldate = {2024-03-01},
journal = {Structure},
abstract = {The translation factor IF5A is highly conserved in Eukarya and Archaea and undergoes a unique post-translational hypusine modification by the deoxyhypusine synthase (DHS) enzyme. DHS transfers the butylamine moiety from spermidine to IF5A using NAD as a cofactor, forming a deoxyhypusine intermediate. IF5A is a key player in protein synthesis, preventing ribosome stalling in proline-rich sequences during translation elongation and facilitating translation elongation and termination. Additionally, human eIF5A participates in various essential cellular processes and contributes to cancer metastasis, with inhibiting hypusination showing anti-proliferative effects. The hypusination pathway of IF5A is therefore an attractive new therapeutic target. We elucidated the 2.0 Å X-ray crystal structure of the archaeal DHS-IF5A complex, revealing hetero-octameric architecture and providing a detailed view of the complex active site including the hypusination loop. This structure, along with biophysical data and molecular dynamics simulations, provides new insights into the catalytic mechanism of the hypusination reaction.},
keywords = {ARN-MS, ENNIFAR, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
The translation factor IF5A is highly conserved in Eukarya and Archaea and undergoes a unique post-translational hypusine modification by the deoxyhypusine synthase (DHS) enzyme. DHS transfers the butylamine moiety from spermidine to IF5A using NAD as a cofactor, forming a deoxyhypusine intermediate. IF5A is a key player in protein synthesis, preventing ribosome stalling in proline-rich sequences during translation elongation and facilitating translation elongation and termination. Additionally, human eIF5A participates in various essential cellular processes and contributes to cancer metastasis, with inhibiting hypusination showing anti-proliferative effects. The hypusination pathway of IF5A is therefore an attractive new therapeutic target. We elucidated the 2.0 Å X-ray crystal structure of the archaeal DHS-IF5A complex, revealing hetero-octameric architecture and providing a detailed view of the complex active site including the hypusination loop. This structure, along with biophysical data and molecular dynamics simulations, provides new insights into the catalytic mechanism of the hypusination reaction.
Compain Guillaume, Monsarrat Clément, Blagojevic Julie, Brillet Karl, Dumas Philippe, Hammann Philippe, Kuhn Lauriane, Martiel Isabelle, Engilberge Sylvain, Oliéric Vincent, Wolff Philippe, Burnouf Dominique Y, Wagner Jérôme, Guichard Gilles
Peptide-Based Covalent Inhibitors Bearing Mild Electrophiles to Target a Conserved His Residue of the Bacterial Sliding Clamp Article de journal
Dans: JACS Au, vol. 4, no. 2, p. 432–440, 2024, ISSN: 2691-3704.
Résumé | Liens | BibTeX | Étiquettes: ARN-MS, ENNIFAR, PPSE, Unité ARN
@article{pmid38425897,
title = {Peptide-Based Covalent Inhibitors Bearing Mild Electrophiles to Target a Conserved His Residue of the Bacterial Sliding Clamp},
author = {Guillaume Compain and Clément Monsarrat and Julie Blagojevic and Karl Brillet and Philippe Dumas and Philippe Hammann and Lauriane Kuhn and Isabelle Martiel and Sylvain Engilberge and Vincent Oliéric and Philippe Wolff and Dominique Y Burnouf and Jérôme Wagner and Gilles Guichard},
doi = {10.1021/jacsau.3c00572},
issn = {2691-3704},
year = {2024},
date = {2024-02-01},
urldate = {2024-02-01},
journal = {JACS Au},
volume = {4},
number = {2},
pages = {432--440},
abstract = {Peptide-based covalent inhibitors targeted to nucleophilic protein residues have recently emerged as new modalities to target protein-protein interactions (PPIs) as they may provide some benefits over more classic competitive inhibitors. Covalent inhibitors are generally targeted to cysteine, the most intrinsically reactive amino acid residue, and to lysine, which is more abundant at the surface of proteins but much less frequently to histidine. Herein, we report the structure-guided design of targeted covalent inhibitors (TCIs) able to bind covalently and selectively to the bacterial sliding clamp (SC), by reacting with a well-conserved histidine residue located on the edge of the peptide-binding pocket. SC is an essential component of the bacterial DNA replication machinery, identified as a promising target for the development of new antibacterial compounds. Thermodynamic and kinetic analyses of ligands bearing different mild electrophilic warheads confirmed the higher efficiency of the chloroacetamide compared to Michael acceptors. Two high-resolution X-ray structures of covalent inhibitor-SC adducts were obtained, revealing the canonical orientation of the ligand and details of covalent bond formation with histidine. Proteomic studies were consistent with a selective SC engagement by the chloroacetamide-based TCI. Finally, the TCI of SC was substantially more active than the parent noncovalent inhibitor in an in vitro SC-dependent DNA synthesis assay, validating the potential of the approach to design covalent inhibitors of protein-protein interactions targeted to histidine.},
keywords = {ARN-MS, ENNIFAR, PPSE, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
Peptide-based covalent inhibitors targeted to nucleophilic protein residues have recently emerged as new modalities to target protein-protein interactions (PPIs) as they may provide some benefits over more classic competitive inhibitors. Covalent inhibitors are generally targeted to cysteine, the most intrinsically reactive amino acid residue, and to lysine, which is more abundant at the surface of proteins but much less frequently to histidine. Herein, we report the structure-guided design of targeted covalent inhibitors (TCIs) able to bind covalently and selectively to the bacterial sliding clamp (SC), by reacting with a well-conserved histidine residue located on the edge of the peptide-binding pocket. SC is an essential component of the bacterial DNA replication machinery, identified as a promising target for the development of new antibacterial compounds. Thermodynamic and kinetic analyses of ligands bearing different mild electrophilic warheads confirmed the higher efficiency of the chloroacetamide compared to Michael acceptors. Two high-resolution X-ray structures of covalent inhibitor-SC adducts were obtained, revealing the canonical orientation of the ligand and details of covalent bond formation with histidine. Proteomic studies were consistent with a selective SC engagement by the chloroacetamide-based TCI. Finally, the TCI of SC was substantially more active than the parent noncovalent inhibitor in an in vitro SC-dependent DNA synthesis assay, validating the potential of the approach to design covalent inhibitors of protein-protein interactions targeted to histidine.
Hayek Hassan, Gross Lauriane, Alghoul Fatima, Martin Franck, Eriani Gilbert, Allmang Christine
Immunoprecipitation Methods to Isolate Messenger Ribonucleoprotein Complexes (mRNP) Chapitre d'ouvrage
Dans: vol. 3234, p. 1–15, M. Cristina Vega, Francisco J. Fernández, Springer, 2024, ISSN: 0065-2598.
Résumé | Liens | BibTeX | Étiquettes: ERIANI, MARTIN, PPSE, Unité ARN
@inbook{pmid38507196,
title = {Immunoprecipitation Methods to Isolate Messenger Ribonucleoprotein Complexes (mRNP)},
author = {Hassan Hayek and Lauriane Gross and Fatima Alghoul and Franck Martin and Gilbert Eriani and Christine Allmang},
doi = {10.1007/978-3-031-52193-5_1},
issn = {0065-2598},
year = {2024},
date = {2024-01-01},
urldate = {2024-01-01},
journal = {Adv Exp Med Biol},
volume = {3234},
pages = {1--15},
publisher = {M. Cristina Vega, Francisco J. Fernández},
edition = {Springer},
series = {Advanced Technologies for Protein Complex Production and Characterization},
abstract = {Throughout their life cycle, messenger RNAs (mRNAs) associate with proteins to form ribonucleoproteins (mRNPs). Each mRNA is part of multiple successive mRNP complexes that participate in their biogenesis, cellular localization, translation and decay. The dynamic composition of mRNP complexes and their structural remodelling play crucial roles in the control of gene expression. Studying the endogenous composition of different mRNP complexes is a major challenge. In this chapter, we describe the variety of protein-centric immunoprecipitation methods available for the identification of mRNP complexes and the requirements for their experimental settings.},
keywords = {ERIANI, MARTIN, PPSE, Unité ARN},
pubstate = {published},
tppubtype = {inbook}
}
Throughout their life cycle, messenger RNAs (mRNAs) associate with proteins to form ribonucleoproteins (mRNPs). Each mRNA is part of multiple successive mRNP complexes that participate in their biogenesis, cellular localization, translation and decay. The dynamic composition of mRNP complexes and their structural remodelling play crucial roles in the control of gene expression. Studying the endogenous composition of different mRNP complexes is a major challenge. In this chapter, we describe the variety of protein-centric immunoprecipitation methods available for the identification of mRNP complexes and the requirements for their experimental settings.
Lechner Antony, Wolff Philippe
In-Gel Cyanoethylation for Pseudouridines Mass Spectrometry Detection of Bacterial Regulatory RNA Chapitre d'ouvrage
Dans: Véronique Arluison, Claudio Valverde (Ed.): vol. 2741, p. 273–287, Véronique Arluison, Claudio Valverde, 2024, ISSN: 1940-6029.
Résumé | Liens | BibTeX | Étiquettes: ARN-MS, Unité ARN
@inbook{pmid38217659,
title = {In-Gel Cyanoethylation for Pseudouridines Mass Spectrometry Detection of Bacterial Regulatory RNA},
author = {Antony Lechner and Philippe Wolff},
editor = {Véronique Arluison, Claudio Valverde},
doi = {10.1007/978-1-0716-3565-0_15},
issn = {1940-6029},
year = {2024},
date = {2024-01-01},
urldate = {2024-01-01},
journal = {Methods Mol Biol},
volume = {2741},
pages = {273--287},
publisher = {Véronique Arluison, Claudio Valverde},
series = {Bacterial Regulatory RNA, Methods and Protocols},
abstract = {Regulatory RNAs, as well as many RNA families, contain chemically modified nucleotides, including pseudouridines (ψ). To map nucleotide modifications, approaches based on enzymatic digestion of RNA followed by nano liquid chromatography-tandem mass spectrometry (nanoLC-MS/MS) analysis were implemented several years ago. However, detection of ψ by mass spectrometry (MS) is challenging as ψ exhibits the same mass as uridine. Thus, a chemical labeling strategy using acrylonitrile was developed to detect this mass-silent modification. Acrylonitrile reacts specifically to ψ to form 1-cyanoethylpseudouridine (Ceψ), resulting in a mass shift of ψ detectable by MS. Here, a protocol detailing the steps from the purification of RNA by polyacrylamide gel electrophoresis, including in-gel labeling of ψ, to MS data interpretation to map ψ and other modifications is proposed. To demonstrate its efficiency, the protocol was applied to bacterial regulatory RNAs from E. coli: 6S RNA and transfer-messenger RNA (tmRNA, also known as 10Sa RNA). Moreover, ribonuclease P (RNase P) was also mapped using this approach. This method enabled the detection of several ψ at single nucleotide resolution.},
keywords = {ARN-MS, Unité ARN},
pubstate = {published},
tppubtype = {inbook}
}
Regulatory RNAs, as well as many RNA families, contain chemically modified nucleotides, including pseudouridines (ψ). To map nucleotide modifications, approaches based on enzymatic digestion of RNA followed by nano liquid chromatography-tandem mass spectrometry (nanoLC-MS/MS) analysis were implemented several years ago. However, detection of ψ by mass spectrometry (MS) is challenging as ψ exhibits the same mass as uridine. Thus, a chemical labeling strategy using acrylonitrile was developed to detect this mass-silent modification. Acrylonitrile reacts specifically to ψ to form 1-cyanoethylpseudouridine (Ceψ), resulting in a mass shift of ψ detectable by MS. Here, a protocol detailing the steps from the purification of RNA by polyacrylamide gel electrophoresis, including in-gel labeling of ψ, to MS data interpretation to map ψ and other modifications is proposed. To demonstrate its efficiency, the protocol was applied to bacterial regulatory RNAs from E. coli: 6S RNA and transfer-messenger RNA (tmRNA, also known as 10Sa RNA). Moreover, ribonuclease P (RNase P) was also mapped using this approach. This method enabled the detection of several ψ at single nucleotide resolution.
2023
Bahena-Ceron Roberto, Teixeira Chloe, Ponce Jose R Jaramillo, Wolff Philippe, Couzon Florence, François Pauline, Klaholz Bruno, Vandenesch François, Romby Pascale, Moreau Karen, Marzi Stefano
RlmQ: A Newly Discovered rRNA Modification Enzyme Bridging RNA Modification and Virulence Traits in Article de journal
Dans: RNA, vol. 30, no. 3, p. 200-212, 2023, ISSN: 1469-9001.
Résumé | Liens | BibTeX | Étiquettes: ARN-MS, ROMBY, Unité ARN
@article{pmid38164596,
title = {RlmQ: A Newly Discovered rRNA Modification Enzyme Bridging RNA Modification and Virulence Traits in },
author = {Roberto Bahena-Ceron and Chloe Teixeira and Jose R Jaramillo Ponce and Philippe Wolff and Florence Couzon and Pauline François and Bruno Klaholz and François Vandenesch and Pascale Romby and Karen Moreau and Stefano Marzi},
doi = {10.1261/rna.079850.123},
issn = {1469-9001},
year = {2023},
date = {2023-12-01},
urldate = {2023-12-01},
journal = {RNA},
volume = {30},
number = {3},
pages = {200-212},
abstract = {rRNA modifications play crucial roles in fine-tuning the delicate balance between translation speed and accuracy, yet the underlying mechanisms remain elusive. Comparative analyses of the ribosomal RNA modifications in taxonomically distant bacteria could help define their general, as well as species-specific, roles. In this study, we identified a new methyltransferase, RlmQ, in responsible for the Gram-positive specific mG2601, which is not modified in (G2574). We also demonstrate the absence of methylation on C1989, equivalent to C1962, which is methylated at position 5 by the Gram-negative specific RlmI methyltransferase, a paralogue of RlmQ. Both modifications ( mG2601 and mC1962) are situated within the same tRNA accommodation corridor, hinting at a potential shared function in translation. Inactivation of Q causes the loss of methylation at G2601 and significantly impacts growth, cytotoxicity, and biofilm formation. These findings unravel the intricate connections between rRNA modifications, translation, and virulence in pathogenic Gram-positive bacteria.},
keywords = {ARN-MS, ROMBY, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
rRNA modifications play crucial roles in fine-tuning the delicate balance between translation speed and accuracy, yet the underlying mechanisms remain elusive. Comparative analyses of the ribosomal RNA modifications in taxonomically distant bacteria could help define their general, as well as species-specific, roles. In this study, we identified a new methyltransferase, RlmQ, in responsible for the Gram-positive specific mG2601, which is not modified in (G2574). We also demonstrate the absence of methylation on C1989, equivalent to C1962, which is methylated at position 5 by the Gram-negative specific RlmI methyltransferase, a paralogue of RlmQ. Both modifications ( mG2601 and mC1962) are situated within the same tRNA accommodation corridor, hinting at a potential shared function in translation. Inactivation of Q causes the loss of methylation at G2601 and significantly impacts growth, cytotoxicity, and biofilm formation. These findings unravel the intricate connections between rRNA modifications, translation, and virulence in pathogenic Gram-positive bacteria.
Arrivé Mathilde, Bruggeman Mathieu, Skaltsogiannis Vasileios, Coudray Léna, Quan Yi-Fat, Schelcher Cédric, Cognat Valérie, Hammann Philippe, Chicher Johana, Wolff Philippe, Gobert Anthony, Giegé Philippe
A tRNA-modifying enzyme facilitates RNase P activity in Arabidopsis nuclei Article de journal
Dans: Nat Plants, vol. 9, iss. 12, p. 2031-2041, 2023, ISSN: 2055-0278.
Résumé | Liens | BibTeX | Étiquettes: ARN-MS, PPSE, Unité ARN
@article{pmid37945696,
title = {A tRNA-modifying enzyme facilitates RNase P activity in Arabidopsis nuclei},
author = {Mathilde Arrivé and Mathieu Bruggeman and Vasileios Skaltsogiannis and Léna Coudray and Yi-Fat Quan and Cédric Schelcher and Valérie Cognat and Philippe Hammann and Johana Chicher and Philippe Wolff and Anthony Gobert and Philippe Giegé},
doi = {10.1038/s41477-023-01564-0},
issn = {2055-0278},
year = {2023},
date = {2023-11-01},
urldate = {2023-11-01},
journal = {Nat Plants},
volume = {9},
issue = {12},
pages = {2031-2041},
abstract = {RNase P is the essential activity that performs the 5' maturation of transfer RNA (tRNA) precursors. Beyond the ancestral form of RNase P containing a ribozyme, protein-only RNase P enzymes termed PRORP were identified in eukaryotes. In human mitochondria, PRORP forms a complex with two protein partners to become functional. In plants, although PRORP enzymes are active alone, we investigate their interaction network to identify potential tRNA maturation complexes. Here we investigate functional interactions involving the Arabidopsis nuclear RNase P PRORP2. We show, using an immuno-affinity strategy, that PRORP2 occurs in a complex with the tRNA methyl transferases TRM1A and TRM1B in vivo. Beyond RNase P, these enzymes can also interact with RNase Z. We show that TRM1A/TRM1B localize in the nucleus and find that their double knockout mutation results in a severe macroscopic phenotype. Using a combination of immuno-detections, mass spectrometry and a transcriptome-wide tRNA sequencing approach, we observe that TRM1A/TRM1B are responsible for the mG26 modification of 70% of cytosolic tRNAs in vivo. We use the transcriptome wide tRNAseq approach as well as RNA blot hybridizations to show that RNase P activity is impaired in TRM1A/TRM1B mutants for specific tRNAs, in particular, tRNAs containing a mG modification at position 26 that are strongly downregulated in TRM1A/TRM1B mutants. Altogether, results indicate that the mG-adding enzymes TRM1A/TRM1B functionally cooperate with nuclear RNase P in vivo for the early steps of cytosolic tRNA biogenesis.},
keywords = {ARN-MS, PPSE, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
RNase P is the essential activity that performs the 5' maturation of transfer RNA (tRNA) precursors. Beyond the ancestral form of RNase P containing a ribozyme, protein-only RNase P enzymes termed PRORP were identified in eukaryotes. In human mitochondria, PRORP forms a complex with two protein partners to become functional. In plants, although PRORP enzymes are active alone, we investigate their interaction network to identify potential tRNA maturation complexes. Here we investigate functional interactions involving the Arabidopsis nuclear RNase P PRORP2. We show, using an immuno-affinity strategy, that PRORP2 occurs in a complex with the tRNA methyl transferases TRM1A and TRM1B in vivo. Beyond RNase P, these enzymes can also interact with RNase Z. We show that TRM1A/TRM1B localize in the nucleus and find that their double knockout mutation results in a severe macroscopic phenotype. Using a combination of immuno-detections, mass spectrometry and a transcriptome-wide tRNA sequencing approach, we observe that TRM1A/TRM1B are responsible for the mG26 modification of 70% of cytosolic tRNAs in vivo. We use the transcriptome wide tRNAseq approach as well as RNA blot hybridizations to show that RNase P activity is impaired in TRM1A/TRM1B mutants for specific tRNAs, in particular, tRNAs containing a mG modification at position 26 that are strongly downregulated in TRM1A/TRM1B mutants. Altogether, results indicate that the mG-adding enzymes TRM1A/TRM1B functionally cooperate with nuclear RNase P in vivo for the early steps of cytosolic tRNA biogenesis.
Silva P Malaka De, Bennett Rebecca J, Kuhn Lauriane, Ngondo Patryk, Debande Lorine, Njamkepo Elisabeth, Ho Brian, Weill François-Xavier, Marteyn Benoît S, Jenkins Claire, Baker Kate S
Escherichia coli killing by epidemiologically successful sublineages of Shigella sonnei is mediated by colicins Article de journal
Dans: EBioMedicine, vol. 97, p. 104822, 2023, ISSN: 2352-3964.
Résumé | Liens | BibTeX | Étiquettes: MARTEYN, PPSE, Unité ARN
@article{pmid37806286,
title = {Escherichia coli killing by epidemiologically successful sublineages of Shigella sonnei is mediated by colicins},
author = {P Malaka De Silva and Rebecca J Bennett and Lauriane Kuhn and Patryk Ngondo and Lorine Debande and Elisabeth Njamkepo and Brian Ho and François-Xavier Weill and Benoît S Marteyn and Claire Jenkins and Kate S Baker},
doi = {10.1016/j.ebiom.2023.104822},
issn = {2352-3964},
year = {2023},
date = {2023-10-01},
urldate = {2023-10-01},
journal = {EBioMedicine},
volume = {97},
pages = {104822},
abstract = {BACKGROUND: Shigella sp. are enteric pathogens which causes >125 million cases of shigellosis annually. S. sonnei accounts for about a quarter of those cases and is increasingly prevalent in industrialising nations. Being an enteric pathogen, S. sonnei benefits from outcompeting gut commensals such as Escherichia coli to establish itself and cause disease. There are numerous mechanisms that bacterial pathogens use to outcompete its rivals including molecules called colicins. A Type 6 Secretion System (T6SS) was recently described as contributing to E. coli killing in S. sonnei.nnMETHODS: We used Bulk Phenotyping of Epidemiological Replicates (BPER) which combined bacterial Genome Wide Association Studies (bGWAS) and high throughput phenotyping on a collection of S. sonnei surveillance isolates to identify the genetic features associated with E. coli killing and explore their relationship with epidemiological behaviour. We further explored the presence of colicins and T6SS components in the isolates using genomics, laboratory experimentation, and proteomics.nnFINDINGS: Our bGWAS analysis returned known and novel colicin and colicin related genes as significantly associated with E. coli killing. In silico analyses identified key colicin clusters responsible for the killing phenotype associated with epidemiologically successful sub-lineages. The killing phenotype was not associated with the presence of a T6SS. Laboratory analyses confirmed the presence of the key colicin clusters and that killing was contact-independent.nnINTERPRETATION: Colicins are responsible for E. coli killing by S. sonnei, not a T6SS. This phenotype contributes to shaping the observed epidemiology of S. sonnei and may contribute to its increasing prevalence globally. BPER is an epidemiologically relevant approach to phenotypic testing that enables the rapid identification of genetic drivers of phenotypic changes, and assessment of their relevance to epidemiology in natural settings.nnFUNDING: Biotechnology and Biological Sciences Research Council, Biotechnology and Biological Sciences Research Council Doctoral Training Partnership studentship, Wellcome Trust, Medical Research Council (UK), French National Research Agency.},
keywords = {MARTEYN, PPSE, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
BACKGROUND: Shigella sp. are enteric pathogens which causes >125 million cases of shigellosis annually. S. sonnei accounts for about a quarter of those cases and is increasingly prevalent in industrialising nations. Being an enteric pathogen, S. sonnei benefits from outcompeting gut commensals such as Escherichia coli to establish itself and cause disease. There are numerous mechanisms that bacterial pathogens use to outcompete its rivals including molecules called colicins. A Type 6 Secretion System (T6SS) was recently described as contributing to E. coli killing in S. sonnei.nnMETHODS: We used Bulk Phenotyping of Epidemiological Replicates (BPER) which combined bacterial Genome Wide Association Studies (bGWAS) and high throughput phenotyping on a collection of S. sonnei surveillance isolates to identify the genetic features associated with E. coli killing and explore their relationship with epidemiological behaviour. We further explored the presence of colicins and T6SS components in the isolates using genomics, laboratory experimentation, and proteomics.nnFINDINGS: Our bGWAS analysis returned known and novel colicin and colicin related genes as significantly associated with E. coli killing. In silico analyses identified key colicin clusters responsible for the killing phenotype associated with epidemiologically successful sub-lineages. The killing phenotype was not associated with the presence of a T6SS. Laboratory analyses confirmed the presence of the key colicin clusters and that killing was contact-independent.nnINTERPRETATION: Colicins are responsible for E. coli killing by S. sonnei, not a T6SS. This phenotype contributes to shaping the observed epidemiology of S. sonnei and may contribute to its increasing prevalence globally. BPER is an epidemiologically relevant approach to phenotypic testing that enables the rapid identification of genetic drivers of phenotypic changes, and assessment of their relevance to epidemiology in natural settings.nnFUNDING: Biotechnology and Biological Sciences Research Council, Biotechnology and Biological Sciences Research Council Doctoral Training Partnership studentship, Wellcome Trust, Medical Research Council (UK), French National Research Agency.
Vindry Caroline, Guillin Olivia, Wolff Philippe, Marie Paul, Mortreux Franck, Mangeot Philippe E, Ohlmann Théophile, Chavatte Laurent
A homozygous mutation in the human selenocysteine tRNA gene impairs UGA recoding activity and selenoproteome regulation by selenium Article de journal
Dans: Nucleic Acids Res, vol. 51, iss. 14, p. 7580-7601, 2023, ISSN: 1362-4962.
Résumé | Liens | BibTeX | Étiquettes: ARN-MS, Unité ARN
@article{pmid37254812,
title = {A homozygous mutation in the human selenocysteine tRNA gene impairs UGA recoding activity and selenoproteome regulation by selenium},
author = {Caroline Vindry and Olivia Guillin and Philippe Wolff and Paul Marie and Franck Mortreux and Philippe E Mangeot and Théophile Ohlmann and Laurent Chavatte},
doi = {10.1093/nar/gkad482},
issn = {1362-4962},
year = {2023},
date = {2023-05-01},
urldate = {2023-05-01},
journal = {Nucleic Acids Res},
volume = {51},
issue = {14},
pages = {7580-7601},
abstract = {The selenocysteine (Sec) tRNA (tRNA[Ser]Sec) governs Sec insertion into selenoproteins by the recoding of a UGA codon, typically used as a stop codon. A homozygous point mutation (C65G) in the human tRNA[Ser]Sec acceptor arm has been reported by two independent groups and was associated with symptoms such as thyroid dysfunction and low blood selenium levels; however, the extent of altered selenoprotein synthesis resulting from this mutation has yet to be comprehensively investigated. In this study, we used CRISPR/Cas9 technology to engineer homozygous and heterozygous mutant human cells, which we then compared with the parental cell lines. This C65G mutation affected many aspects of tRNA[Ser]Sec integrity and activity. Firstly, the expression level of tRNA[Ser]Sec was significantly reduced due to an altered recruitment of RNA polymerase III at the promoter. Secondly, selenoprotein expression was strongly altered, but, more surprisingly, it was no longer sensitive to selenium supplementation. Mass spectrometry analyses revealed a tRNA isoform with unmodified wobble nucleotide U34 in mutant cells that correlated with reduced UGA recoding activities. Overall, this study demonstrates the pleiotropic effect of a single C65G mutation on both tRNA phenotype and selenoproteome expression.},
keywords = {ARN-MS, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
The selenocysteine (Sec) tRNA (tRNA[Ser]Sec) governs Sec insertion into selenoproteins by the recoding of a UGA codon, typically used as a stop codon. A homozygous point mutation (C65G) in the human tRNA[Ser]Sec acceptor arm has been reported by two independent groups and was associated with symptoms such as thyroid dysfunction and low blood selenium levels; however, the extent of altered selenoprotein synthesis resulting from this mutation has yet to be comprehensively investigated. In this study, we used CRISPR/Cas9 technology to engineer homozygous and heterozygous mutant human cells, which we then compared with the parental cell lines. This C65G mutation affected many aspects of tRNA[Ser]Sec integrity and activity. Firstly, the expression level of tRNA[Ser]Sec was significantly reduced due to an altered recruitment of RNA polymerase III at the promoter. Secondly, selenoprotein expression was strongly altered, but, more surprisingly, it was no longer sensitive to selenium supplementation. Mass spectrometry analyses revealed a tRNA isoform with unmodified wobble nucleotide U34 in mutant cells that correlated with reduced UGA recoding activities. Overall, this study demonstrates the pleiotropic effect of a single C65G mutation on both tRNA phenotype and selenoproteome expression.
Girardi Erika, Messmer Mélanie, Lopez Paula, Fender Aurélie, Chicher Johana, Chane-Woon-Ming Béatrice, Hammann Philippe, Pfeffer Sébastien
Proteomics-based determination of double-stranded RNA interactome reveals known and new factors involved in Sindbis virus infection Article de journal
Dans: RNA, vol. 29, no. 3, p. 361–375, 2023, ISSN: 1469-9001.
Résumé | Liens | BibTeX | Étiquettes: PFEFFER, PPSE, Unité ARN
@article{pmid36617674b,
title = {Proteomics-based determination of double-stranded RNA interactome reveals known and new factors involved in Sindbis virus infection},
author = {Erika Girardi and Mélanie Messmer and Paula Lopez and Aurélie Fender and Johana Chicher and Béatrice Chane-Woon-Ming and Philippe Hammann and Sébastien Pfeffer},
doi = {10.1261/rna.079270.122},
issn = {1469-9001},
year = {2023},
date = {2023-03-01},
urldate = {2023-03-01},
journal = {RNA},
volume = {29},
number = {3},
pages = {361--375},
abstract = {Viruses are obligate intracellular parasites, which depend on the host cellular machineries to replicate their genome and complete their infectious cycle. Long double-stranded (ds)RNA is a common viral by-product originating during RNA virus replication and is universally sensed as a danger signal to trigger the antiviral response. As a result, viruses hide dsRNA intermediates into viral replication factories and have evolved strategies to hijack cellular proteins for their benefit. The characterization of the host factors associated with viral dsRNA and involved in viral replication remains a major challenge to develop new antiviral drugs against RNA viruses. Here, we performed anti-dsRNA immunoprecipitation followed by mass spectrometry analysis to fully characterize the dsRNA interactome in Sindbis virus (SINV) infected human cells. Among the identified proteins, we characterized SFPQ (splicing factor, proline-glutamine rich) as a new dsRNA-associated proviral factor upon SINV infection. We showed that SFPQ depletion reduces SINV infection in human HCT116 and SK-N-BE(2) cells, suggesting that SFPQ enhances viral production. We demonstrated that the cytoplasmic fraction of SFPQ partially colocalizes with dsRNA upon SINV infection. In agreement, we proved by RNA-IP that SFPQ can bind dsRNA and viral RNA. Furthermore, we showed that overexpression of a wild-type, but not an RNA binding mutant SFPQ, increased viral infection, suggesting that RNA binding is essential for its positive effect on the virus. Overall, this study provides the community with a compendium of dsRNA-associated factors during viral infection and identifies SFPQ as a new proviral dsRNA binding protein.},
keywords = {PFEFFER, PPSE, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
Viruses are obligate intracellular parasites, which depend on the host cellular machineries to replicate their genome and complete their infectious cycle. Long double-stranded (ds)RNA is a common viral by-product originating during RNA virus replication and is universally sensed as a danger signal to trigger the antiviral response. As a result, viruses hide dsRNA intermediates into viral replication factories and have evolved strategies to hijack cellular proteins for their benefit. The characterization of the host factors associated with viral dsRNA and involved in viral replication remains a major challenge to develop new antiviral drugs against RNA viruses. Here, we performed anti-dsRNA immunoprecipitation followed by mass spectrometry analysis to fully characterize the dsRNA interactome in Sindbis virus (SINV) infected human cells. Among the identified proteins, we characterized SFPQ (splicing factor, proline-glutamine rich) as a new dsRNA-associated proviral factor upon SINV infection. We showed that SFPQ depletion reduces SINV infection in human HCT116 and SK-N-BE(2) cells, suggesting that SFPQ enhances viral production. We demonstrated that the cytoplasmic fraction of SFPQ partially colocalizes with dsRNA upon SINV infection. In agreement, we proved by RNA-IP that SFPQ can bind dsRNA and viral RNA. Furthermore, we showed that overexpression of a wild-type, but not an RNA binding mutant SFPQ, increased viral infection, suggesting that RNA binding is essential for its positive effect on the virus. Overall, this study provides the community with a compendium of dsRNA-associated factors during viral infection and identifies SFPQ as a new proviral dsRNA binding protein.
Gosset-Erard Clarisse, Didierjean Mévie, Pansanel Jérome, Lechner Antony, Wolff Philippe, Kuhn Lauriane, Aubriet Frédéric, Leize-Wagner Emmanuelle, Chaimbault Patrick, François Yannis-Nicolas
Nucleos'ID: A New Search Engine Enabling the Untargeted Identification of RNA Post-transcriptional Modifications from Tandem Mass Spectrometry Analyses of Nucleosides Article de journal
Dans: Anal Chem, vol. 95, iss. 2, p. 1608-1617, 2023, ISSN: 1520-6882.
Résumé | Liens | BibTeX | Étiquettes: ARN-MS, PPSE, Unité ARN
@article{pmid36598775,
title = {Nucleos'ID: A New Search Engine Enabling the Untargeted Identification of RNA Post-transcriptional Modifications from Tandem Mass Spectrometry Analyses of Nucleosides},
author = {Clarisse Gosset-Erard and Mévie Didierjean and Jérome Pansanel and Antony Lechner and Philippe Wolff and Lauriane Kuhn and Frédéric Aubriet and Emmanuelle Leize-Wagner and Patrick Chaimbault and Yannis-Nicolas François},
doi = {10.1021/acs.analchem.2c04722},
issn = {1520-6882},
year = {2023},
date = {2023-01-01},
urldate = {2023-01-01},
journal = {Anal Chem},
volume = {95},
issue = {2},
pages = {1608-1617},
abstract = {As RNA post-transcriptional modifications are of growing interest, several methods were developed for their characterization. One of them established for their identification, at the nucleosidic level, is the hyphenation of separation methods, such as liquid chromatography or capillary electrophoresis, to tandem mass spectrometry. However, to our knowledge, no software is yet available for the untargeted identification of RNA post-transcriptional modifications from MS/MS data-dependent acquisitions. Thus, very long and tedious manual data interpretations are required. To meet the need of easier and faster data interpretation, a new user-friendly search engine, called Nucleos'ID, was developed for CE-MS/MS and LC-MS/MS users. Performances of this new software were evaluated on CE-MS/MS data from nucleoside analyses of already well-described transfer RNA and total tRNA extract. All samples showed great true positive, true negative, and false discovery rates considering the database size containing all modified and unmodified nucleosides referenced in the literature. The true positive and true negative rates obtained were above 0.94, while the false discovery rates were between 0.09 and 0.17. To increase the level of sample complexity, untargeted identification of several RNA modifications from 70S ribosome was achieved by the Nucleos'ID search following CE-MS/MS analysis.},
keywords = {ARN-MS, PPSE, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
As RNA post-transcriptional modifications are of growing interest, several methods were developed for their characterization. One of them established for their identification, at the nucleosidic level, is the hyphenation of separation methods, such as liquid chromatography or capillary electrophoresis, to tandem mass spectrometry. However, to our knowledge, no software is yet available for the untargeted identification of RNA post-transcriptional modifications from MS/MS data-dependent acquisitions. Thus, very long and tedious manual data interpretations are required. To meet the need of easier and faster data interpretation, a new user-friendly search engine, called Nucleos'ID, was developed for CE-MS/MS and LC-MS/MS users. Performances of this new software were evaluated on CE-MS/MS data from nucleoside analyses of already well-described transfer RNA and total tRNA extract. All samples showed great true positive, true negative, and false discovery rates considering the database size containing all modified and unmodified nucleosides referenced in the literature. The true positive and true negative rates obtained were above 0.94, while the false discovery rates were between 0.09 and 0.17. To increase the level of sample complexity, untargeted identification of several RNA modifications from 70S ribosome was achieved by the Nucleos'ID search following CE-MS/MS analysis.
Kuhn Lauriane, Vincent Timothée, Hammann Philippe, Zuber Hélène
Exploring Protein Interactome Data with IPinquiry: Statistical Analysis and Data Visualization by Spectral Counts Article de journal
Dans: Methods Mol Biol, vol. 2426, p. 243–265, 2023, ISSN: 1940-6029.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{pmid36308692,
title = {Exploring Protein Interactome Data with IPinquiry: Statistical Analysis and Data Visualization by Spectral Counts},
author = {Lauriane Kuhn and Timothée Vincent and Philippe Hammann and Hélène Zuber},
doi = {10.1007/978-1-0716-1967-4_11},
issn = {1940-6029},
year = {2023},
date = {2023-01-01},
journal = {Methods Mol Biol},
volume = {2426},
pages = {243--265},
abstract = {Immunoprecipitation mass spectrometry (IP-MS) is a popular method for the identification of protein-protein interactions. This approach is particularly powerful when information is collected without a priori knowledge and has been successively used as a first key step for the elucidation of many complex protein networks. IP-MS consists in the affinity purification of a protein of interest and of its interacting proteins followed by protein identification and quantification by mass spectrometry analysis. We developed an R package, named IPinquiry, dedicated to IP-MS analysis and based on the spectral count quantification method. The main purpose of this package is to provide a simple R pipeline with a limited number of processing steps to facilitate data exploration for biologists. This package allows to perform differential analysis of protein accumulation between two groups of IP experiments, to retrieve protein annotations, to export results, and to create different types of graphics. Here we describe the step-by-step procedure for an interactome analysis using IPinquiry from data loading to result export and plot production.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
Immunoprecipitation mass spectrometry (IP-MS) is a popular method for the identification of protein-protein interactions. This approach is particularly powerful when information is collected without a priori knowledge and has been successively used as a first key step for the elucidation of many complex protein networks. IP-MS consists in the affinity purification of a protein of interest and of its interacting proteins followed by protein identification and quantification by mass spectrometry analysis. We developed an R package, named IPinquiry, dedicated to IP-MS analysis and based on the spectral count quantification method. The main purpose of this package is to provide a simple R pipeline with a limited number of processing steps to facilitate data exploration for biologists. This package allows to perform differential analysis of protein accumulation between two groups of IP experiments, to retrieve protein annotations, to export results, and to create different types of graphics. Here we describe the step-by-step procedure for an interactome analysis using IPinquiry from data loading to result export and plot production.
2022
Girardi Erika, Messmer Melanie, Lopez Paula, Fender Aurelie, Chicher Johana, Chane-Woon-Ming Beatrice, Hammann Philippe, Pfeffer Sebastien
Proteomics-based determination of double stranded RNA interactome reveals known and new factors involved in Sindbis virus infection Article de journal
Dans: RNA, vol. 29, iss. 3, p. 361-375, 2022, ISSN: 1469-9001.
Résumé | Liens | BibTeX | Étiquettes: PFEFFER, PPSE, Unité ARN
@article{pmid36617674,
title = {Proteomics-based determination of double stranded RNA interactome reveals known and new factors involved in Sindbis virus infection},
author = {Erika Girardi and Melanie Messmer and Paula Lopez and Aurelie Fender and Johana Chicher and Beatrice Chane-Woon-Ming and Philippe Hammann and Sebastien Pfeffer},
doi = {10.1261/rna.079270.122},
issn = {1469-9001},
year = {2022},
date = {2022-12-01},
urldate = {2022-12-01},
journal = {RNA},
volume = {29},
issue = {3},
pages = {361-375},
abstract = {Viruses are obligate intracellular parasites, which depend on the host cellular machineries to replicate their genome and complete their infectious cycle. Long double stranded (ds)RNA is a common viral by-product originating during RNA virus replication and is universally sensed as a danger signal to trigger the antiviral response. As a result, viruses hide dsRNA intermediates into viral replication factories and have evolved strategies to hijack cellular proteins for their benefit. The characterization of the host factors associated with viral dsRNA and involved in viral replication remains a major challenge to develop new antiviral drugs against RNA viruses. Here, we performed anti-dsRNA immunoprecipitation followed by mass spectrometry analysis to fully characterize the dsRNA interactome in Sindbis virus (SINV) infected human cells. Among the identified proteins, we characterized SFPQ (Splicing factor, proline-glutamine rich) as a new dsRNA-associated proviral factor upon SINV infection. We showed that SFPQ depletion reduces SINV infection in human HCT116 and SK-N-BE(2) cells, suggesting that SFPQ enhances viral production. We demonstrated that the cytoplasmic fraction of SFPQ partially colocalizes with dsRNA upon SINV infection. In agreement, we proved by RNA-IP that SFPQ can bind dsRNA and viral RNA. Furthermore, we showed that overexpression of a wild type, but not an RNA binding mutant SFPQ, increased viral infection, suggesting that RNA binding is essential for its positive effect on the virus. Overall, this study provides the community with a compendium of dsRNA-associated factors during viral infection and identifies SFPQ as a new proviral dsRNA binding protein.},
keywords = {PFEFFER, PPSE, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
Viruses are obligate intracellular parasites, which depend on the host cellular machineries to replicate their genome and complete their infectious cycle. Long double stranded (ds)RNA is a common viral by-product originating during RNA virus replication and is universally sensed as a danger signal to trigger the antiviral response. As a result, viruses hide dsRNA intermediates into viral replication factories and have evolved strategies to hijack cellular proteins for their benefit. The characterization of the host factors associated with viral dsRNA and involved in viral replication remains a major challenge to develop new antiviral drugs against RNA viruses. Here, we performed anti-dsRNA immunoprecipitation followed by mass spectrometry analysis to fully characterize the dsRNA interactome in Sindbis virus (SINV) infected human cells. Among the identified proteins, we characterized SFPQ (Splicing factor, proline-glutamine rich) as a new dsRNA-associated proviral factor upon SINV infection. We showed that SFPQ depletion reduces SINV infection in human HCT116 and SK-N-BE(2) cells, suggesting that SFPQ enhances viral production. We demonstrated that the cytoplasmic fraction of SFPQ partially colocalizes with dsRNA upon SINV infection. In agreement, we proved by RNA-IP that SFPQ can bind dsRNA and viral RNA. Furthermore, we showed that overexpression of a wild type, but not an RNA binding mutant SFPQ, increased viral infection, suggesting that RNA binding is essential for its positive effect on the virus. Overall, this study provides the community with a compendium of dsRNA-associated factors during viral infection and identifies SFPQ as a new proviral dsRNA binding protein.
Chaignaud Pauline, Gruffaz Christelle, Borreca Adrien, Fouteau Stéphanie, Kuhn Lauriane, Masbou Jérémy, Rouy Zoé, Hammann Philippe, Imfeld Gwenaël, Roche David, Vuilleumier Stéphane
A Methylotrophic Bacterium Growing with the Antidiabetic Drug Metformin as Its Sole Carbon, Nitrogen and Energy Source Article de journal
Dans: Microorganisms, vol. 10, no. 11, 2022, ISSN: 2076-2607.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{pmid36422372,
title = {A Methylotrophic Bacterium Growing with the Antidiabetic Drug Metformin as Its Sole Carbon, Nitrogen and Energy Source},
author = {Pauline Chaignaud and Christelle Gruffaz and Adrien Borreca and Stéphanie Fouteau and Lauriane Kuhn and Jérémy Masbou and Zoé Rouy and Philippe Hammann and Gwenaël Imfeld and David Roche and Stéphane Vuilleumier},
doi = {10.3390/microorganisms10112302},
issn = {2076-2607},
year = {2022},
date = {2022-11-01},
journal = {Microorganisms},
volume = {10},
number = {11},
abstract = {Metformin is one of the most prescribed antidiabetic agents worldwide and is also considered for other therapeutic applications including cancer and endocrine disorders. It is largely unmetabolized by human enzymes and its presence in the environment has raised concern, with reported toxic effects on aquatic life and potentially also on humans. We report on the isolation and characterisation of strain MD1, an aerobic methylotrophic bacterium growing with metformin as its sole carbon, nitrogen and energy source. Strain MD1 degrades metformin into dimethylamine used for growth, and guanylurea as a side-product. Sequence analysis of its fully assembled genome showed its affiliation to . Differential proteomics and transcriptomics, as well as mini-transposon mutagenesis of the strain, point to genes and proteins essential for growth with metformin and potentially associated with hydrolytic C-N cleavage of metformin or with cellular transport of metformin and guanylurea. The obtained results suggest the recent evolution of the growth-supporting capacity of strain MD1 to degrade metformin. Our results identify candidate proteins of the enzymatic system for metformin transformation in strain MD1 and will inform future research on the fate of metformin and its degradation products in the environment and in humans.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
Metformin is one of the most prescribed antidiabetic agents worldwide and is also considered for other therapeutic applications including cancer and endocrine disorders. It is largely unmetabolized by human enzymes and its presence in the environment has raised concern, with reported toxic effects on aquatic life and potentially also on humans. We report on the isolation and characterisation of strain MD1, an aerobic methylotrophic bacterium growing with metformin as its sole carbon, nitrogen and energy source. Strain MD1 degrades metformin into dimethylamine used for growth, and guanylurea as a side-product. Sequence analysis of its fully assembled genome showed its affiliation to . Differential proteomics and transcriptomics, as well as mini-transposon mutagenesis of the strain, point to genes and proteins essential for growth with metformin and potentially associated with hydrolytic C-N cleavage of metformin or with cellular transport of metformin and guanylurea. The obtained results suggest the recent evolution of the growth-supporting capacity of strain MD1 to degrade metformin. Our results identify candidate proteins of the enzymatic system for metformin transformation in strain MD1 and will inform future research on the fate of metformin and its degradation products in the environment and in humans.
Hemono Mickaele, Salinas-Giegé Thalia, Roignant Jeanne, Vingadassalon Audrey, Hammann Philippe, Ubrig Elodie, Ngondo Patryk, Duchêne Anne-Marie
FRIENDLY (FMT) is an RNA binding protein associated with cytosolic ribosomes at the mitochondrial surface Article de journal
Dans: Plant J, vol. 112, no. 2, p. 309–321, 2022, ISSN: 1365-313X.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{pmid36050837,
title = {FRIENDLY (FMT) is an RNA binding protein associated with cytosolic ribosomes at the mitochondrial surface},
author = {Mickaele Hemono and Thalia Salinas-Giegé and Jeanne Roignant and Audrey Vingadassalon and Philippe Hammann and Elodie Ubrig and Patryk Ngondo and Anne-Marie Duchêne},
doi = {10.1111/tpj.15962},
issn = {1365-313X},
year = {2022},
date = {2022-10-01},
urldate = {2022-10-01},
journal = {Plant J},
volume = {112},
number = {2},
pages = {309--321},
abstract = {The spatial organization of protein synthesis in the eukaryotic cell is essential for maintaining the integrity of the proteome and the functioning of the cell. Translation on free polysomes or on ribosomes associated with the endoplasmic reticulum has been studied for a long time. More recent data have revealed selective translation of mRNAs in other compartments, in particular at the surface of mitochondria. Although these processes have been described in many organisms, particularky in plants, the mRNA targeting and localized translation mechanisms remain poorly understood. Here, the Arabidopsis thaliana Friendly (FMT) protein is shown to be a cytosolic RNA binding protein that associates with cytosolic ribosomes at the surface of mitochondria. FMT knockout delays seedling development and causes mitochondrial clustering. The mutation also disrupts the mitochondrial proteome, as well as the localization of nuclear transcripts encoding mitochondrial proteins at the surface of mitochondria. These data indicate that FMT participates in the localization of mRNAs and their translation at the surface of mitochondria.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
The spatial organization of protein synthesis in the eukaryotic cell is essential for maintaining the integrity of the proteome and the functioning of the cell. Translation on free polysomes or on ribosomes associated with the endoplasmic reticulum has been studied for a long time. More recent data have revealed selective translation of mRNAs in other compartments, in particular at the surface of mitochondria. Although these processes have been described in many organisms, particularky in plants, the mRNA targeting and localized translation mechanisms remain poorly understood. Here, the Arabidopsis thaliana Friendly (FMT) protein is shown to be a cytosolic RNA binding protein that associates with cytosolic ribosomes at the surface of mitochondria. FMT knockout delays seedling development and causes mitochondrial clustering. The mutation also disrupts the mitochondrial proteome, as well as the localization of nuclear transcripts encoding mitochondrial proteins at the surface of mitochondria. These data indicate that FMT participates in the localization of mRNAs and their translation at the surface of mitochondria.
Fritsch Sarah, Gasser Véronique, Peukert Carsten, Pinkert Lukas, Kuhn Lauriane, Perraud Quentin, Normant Vincent, Brönstrup Mark, Schalk Isabelle J
Uptake Mechanisms and Regulatory Responses to MECAM- and DOTAM-Based Artificial Siderophores and Their Antibiotic Conjugates in Article de journal
Dans: ACS Infect Dis, vol. 8, no. 6, p. 1134–1146, 2022, ISSN: 2373-8227.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{pmid35500104,
title = {Uptake Mechanisms and Regulatory Responses to MECAM- and DOTAM-Based Artificial Siderophores and Their Antibiotic Conjugates in },
author = {Sarah Fritsch and Véronique Gasser and Carsten Peukert and Lukas Pinkert and Lauriane Kuhn and Quentin Perraud and Vincent Normant and Mark Brönstrup and Isabelle J Schalk},
doi = {10.1021/acsinfecdis.2c00049},
issn = {2373-8227},
year = {2022},
date = {2022-06-01},
journal = {ACS Infect Dis},
volume = {8},
number = {6},
pages = {1134--1146},
abstract = {The development of new antibiotics against Gram-negative bacteria has to deal with the low permeability of the outer membrane. This obstacle can be overcome by utilizing siderophore-dependent iron uptake pathways as entrance routes for antibiotic uptake. Iron-chelating siderophores are actively imported by bacteria, and their conjugation to antibiotics allows smuggling the latter into bacterial cells. Synthetic siderophore mimetics based on MECAM (1,3,5-,',″-tris-(2,3-dihydroxybenzoyl)-triaminomethylbenzene) and DOTAM (1,4,7,10-tetrakis(carbamoylmethyl)-1,4,7,10-tetraazacyclododecane) cores, both chelating iron via catechol groups, have been recently applied as versatile carriers of functional cargo. In the present study, we show that MECAM and the MECAM-ampicillin conjugate transport iron into cells via the catechol-type outer membrane transporters PfeA and PirA and DOTAM solely via PirA. Differential proteomics and quantitative real-time polymerase chain reaction (qRT-PCR) showed that MECAM import induced the expression of , whereas led to an increase in the expression of and , a gene conferring ampicillin resistance. The presence of DOTAM did not induce the expression of but upregulated the expression of two zinc transporters ( and ), pointing out that bacteria become zinc starved in the presence of this compound. Iron uptake experiments with radioactive Fe demonstrated that import of this nutrient by MECAM and DOTAM was as efficient as with the natural siderophore enterobactin. The study provides a functional validation for DOTAM- and MECAM-based artificial siderophore mimetics as vehicles for the delivery of cargo into Gram-negative bacteria.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
The development of new antibiotics against Gram-negative bacteria has to deal with the low permeability of the outer membrane. This obstacle can be overcome by utilizing siderophore-dependent iron uptake pathways as entrance routes for antibiotic uptake. Iron-chelating siderophores are actively imported by bacteria, and their conjugation to antibiotics allows smuggling the latter into bacterial cells. Synthetic siderophore mimetics based on MECAM (1,3,5-,',″-tris-(2,3-dihydroxybenzoyl)-triaminomethylbenzene) and DOTAM (1,4,7,10-tetrakis(carbamoylmethyl)-1,4,7,10-tetraazacyclododecane) cores, both chelating iron via catechol groups, have been recently applied as versatile carriers of functional cargo. In the present study, we show that MECAM and the MECAM-ampicillin conjugate transport iron into cells via the catechol-type outer membrane transporters PfeA and PirA and DOTAM solely via PirA. Differential proteomics and quantitative real-time polymerase chain reaction (qRT-PCR) showed that MECAM import induced the expression of , whereas led to an increase in the expression of and , a gene conferring ampicillin resistance. The presence of DOTAM did not induce the expression of but upregulated the expression of two zinc transporters ( and ), pointing out that bacteria become zinc starved in the presence of this compound. Iron uptake experiments with radioactive Fe demonstrated that import of this nutrient by MECAM and DOTAM was as efficient as with the natural siderophore enterobactin. The study provides a functional validation for DOTAM- and MECAM-based artificial siderophore mimetics as vehicles for the delivery of cargo into Gram-negative bacteria.
Roovers Martine L, Labar Geoffray, Wolff Philippe, Feller Andre, Elder Dany Van, Soin Romuald, Gueydan Cyril, Kruys Veronique, Droogmans Louis
The Bacillus subtilis open reading frame ysgA encodes the SPOUT methyltransferase RlmP forming 2'-O-methylguanosine at position 2553 in the A-loop of 23S rRNA Article de journal
Dans: RNA, vol. 28, iss. 9, p. 1185-1196, 2022, ISSN: 1469-9001.
Résumé | Liens | BibTeX | Étiquettes: ARN-MS, ENNIFAR, Unité ARN
@article{pmid35710145b,
title = {The Bacillus subtilis open reading frame ysgA encodes the SPOUT methyltransferase RlmP forming 2'-O-methylguanosine at position 2553 in the A-loop of 23S rRNA},
author = {Martine L Roovers and Geoffray Labar and Philippe Wolff and Andre Feller and Dany Van Elder and Romuald Soin and Cyril Gueydan and Veronique Kruys and Louis Droogmans},
doi = {10.1261/rna.079131.122},
issn = {1469-9001},
year = {2022},
date = {2022-06-01},
urldate = {2022-06-01},
journal = {RNA},
volume = {28},
issue = {9},
pages = {1185-1196},
abstract = {A previous bioinformatic analysis predicted that the ysgA open reading frame of Bacillus subtilis encodes an RNA methyltransferase of the SPOUT superfamily. Here we show that YsgA is the 2'-O-methyltransferase that targets position G2553 (Escherichia coli numbering) of the A-loop of 23S rRNA. This was shown by a combination of biochemical and mass spectrometry approaches using both rRNA extracted from B. subtilis wild-type or ΔysgA cells and in vitro synthesized rRNA. When the target G2553 is mutated, YsgA is able to methylate the ribose of adenosine. However it cannot methylate cytidine nor uridine. The enzyme modifies free 23S rRNA but not the fully assembled ribosome nor the 50S subunit, suggesting that the modification occurs early during ribosome biogenesis. Nevertheless ribosome subunits assembly is unaffected in a B. subtilis ΔysgA mutant strain. The crystal structure of the recombinant YsgA protein, combined with mutagenesis data, outlined in this article highlights a typical SPOUT fold preceded by an L7Ae/L30 (eL8/eL30 in a new nomenclature) N-terminal domain.},
keywords = {ARN-MS, ENNIFAR, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
A previous bioinformatic analysis predicted that the ysgA open reading frame of Bacillus subtilis encodes an RNA methyltransferase of the SPOUT superfamily. Here we show that YsgA is the 2'-O-methyltransferase that targets position G2553 (Escherichia coli numbering) of the A-loop of 23S rRNA. This was shown by a combination of biochemical and mass spectrometry approaches using both rRNA extracted from B. subtilis wild-type or ΔysgA cells and in vitro synthesized rRNA. When the target G2553 is mutated, YsgA is able to methylate the ribose of adenosine. However it cannot methylate cytidine nor uridine. The enzyme modifies free 23S rRNA but not the fully assembled ribosome nor the 50S subunit, suggesting that the modification occurs early during ribosome biogenesis. Nevertheless ribosome subunits assembly is unaffected in a B. subtilis ΔysgA mutant strain. The crystal structure of the recombinant YsgA protein, combined with mutagenesis data, outlined in this article highlights a typical SPOUT fold preceded by an L7Ae/L30 (eL8/eL30 in a new nomenclature) N-terminal domain.
Hacquard Thibaut, Clavel Marion, Baldrich Patricia, Lechner Esther, Pérez-Salamó Imma, Schepetilnikov Mikhail, Derrien Benoît, Dubois Marieke, Hammann Philippe, Kuhn Lauriane, Brun Danaé, Bouteiller Nathalie, Baumberger Nicolas, Vaucheret Hervé, Meyers Blake C, Genschik Pascal
The Arabidopsis F-box protein FBW2 targets AGO1 for degradation to prevent spurious loading of illegitimate small RNA Article de journal
Dans: Cell Rep, vol. 39, no. 2, p. 110671, 2022, ISSN: 2211-1247.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{pmid35417704,
title = {The Arabidopsis F-box protein FBW2 targets AGO1 for degradation to prevent spurious loading of illegitimate small RNA},
author = {Thibaut Hacquard and Marion Clavel and Patricia Baldrich and Esther Lechner and Imma Pérez-Salamó and Mikhail Schepetilnikov and Benoît Derrien and Marieke Dubois and Philippe Hammann and Lauriane Kuhn and Danaé Brun and Nathalie Bouteiller and Nicolas Baumberger and Hervé Vaucheret and Blake C Meyers and Pascal Genschik},
doi = {10.1016/j.celrep.2022.110671},
issn = {2211-1247},
year = {2022},
date = {2022-04-01},
journal = {Cell Rep},
volume = {39},
number = {2},
pages = {110671},
abstract = {RNA silencing is a conserved mechanism in eukaryotes involved in development and defense against viruses. In plants, ARGONAUTE1 (AGO1) protein plays a central role in both microRNA- and small interfering RNA-directed silencing, and its expression is regulated at multiple levels. Here, we report that the F-box protein FBW2 assembles an SCF complex that selectively targets for proteolysis AGO1 when it is unloaded and mutated. Although FBW2 loss of function does not lead to strong growth or developmental defects, it significantly increases RNA-silencing activity. Interestingly, under conditions in which small-RNA accumulation is affected, the failure to degrade AGO1 in fbw2 mutants becomes more deleterious for the plant. Accordingly, the non-degradable AGO1 protein assembles high-molecular-weight complexes and binds illegitimate small RNA, leading to off-target cleavage. Therefore, control of AGO1 homeostasis by FBW2 plays an important role in quality control of RNA silencing.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
RNA silencing is a conserved mechanism in eukaryotes involved in development and defense against viruses. In plants, ARGONAUTE1 (AGO1) protein plays a central role in both microRNA- and small interfering RNA-directed silencing, and its expression is regulated at multiple levels. Here, we report that the F-box protein FBW2 assembles an SCF complex that selectively targets for proteolysis AGO1 when it is unloaded and mutated. Although FBW2 loss of function does not lead to strong growth or developmental defects, it significantly increases RNA-silencing activity. Interestingly, under conditions in which small-RNA accumulation is affected, the failure to degrade AGO1 in fbw2 mutants becomes more deleterious for the plant. Accordingly, the non-degradable AGO1 protein assembles high-molecular-weight complexes and binds illegitimate small RNA, leading to off-target cleavage. Therefore, control of AGO1 homeostasis by FBW2 plays an important role in quality control of RNA silencing.
Schiaffini Marlene, Chicois Clara, Pouclet Aude, Chartier Tiphaine, Ubrig Elodie, Gobert Anthony, Zuber Hélène, Mutterer Jérôme, Chicher Johana, Kuhn Lauriane, Hammann Philippe, Gagliardi Dominique, Garcia Damien
A NYN domain protein directly interacts with DECAPPING1 and is required for phyllotactic pattern Article de journal
Dans: Plant Physiol, vol. 188, no. 2, p. 1174–1188, 2022, ISSN: 1532-2548.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{pmid34791434,
title = {A NYN domain protein directly interacts with DECAPPING1 and is required for phyllotactic pattern},
author = {Marlene Schiaffini and Clara Chicois and Aude Pouclet and Tiphaine Chartier and Elodie Ubrig and Anthony Gobert and Hélène Zuber and Jérôme Mutterer and Johana Chicher and Lauriane Kuhn and Philippe Hammann and Dominique Gagliardi and Damien Garcia},
doi = {10.1093/plphys/kiab529},
issn = {1532-2548},
year = {2022},
date = {2022-02-01},
urldate = {2022-02-01},
journal = {Plant Physiol},
volume = {188},
number = {2},
pages = {1174--1188},
abstract = {In eukaryotes, general mRNA decay requires the decapping complex. The activity of this complex depends on its catalytic subunit, DECAPPING2 (DCP2), and its interaction with decapping enhancers, including its main partner DECAPPING1 (DCP1). Here, we report that in Arabidopsis thaliana, DCP1 also interacts with a NYN domain endoribonuclease, hence named DCP1-ASSOCIATED NYN ENDORIBONUCLEASE 1 (DNE1). Interestingly, we found DNE1 predominantly associated with DCP1, but not with DCP2, and reciprocally, suggesting the existence of two distinct protein complexes. We also showed that the catalytic residues of DNE1 are required to repress the expression of mRNAs in planta upon transient expression. The overexpression of DNE1 in transgenic lines led to growth defects and a similar gene deregulation signature than inactivation of the decapping complex. Finally, the combination of dne1 and dcp2 mutations revealed a functional redundancy between DNE1 and DCP2 in controlling phyllotactic pattern formation. Our work identifies DNE1, a hitherto unknown DCP1 protein partner highly conserved in the plant kingdom and identifies its importance for developmental robustness.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
In eukaryotes, general mRNA decay requires the decapping complex. The activity of this complex depends on its catalytic subunit, DECAPPING2 (DCP2), and its interaction with decapping enhancers, including its main partner DECAPPING1 (DCP1). Here, we report that in Arabidopsis thaliana, DCP1 also interacts with a NYN domain endoribonuclease, hence named DCP1-ASSOCIATED NYN ENDORIBONUCLEASE 1 (DNE1). Interestingly, we found DNE1 predominantly associated with DCP1, but not with DCP2, and reciprocally, suggesting the existence of two distinct protein complexes. We also showed that the catalytic residues of DNE1 are required to repress the expression of mRNAs in planta upon transient expression. The overexpression of DNE1 in transgenic lines led to growth defects and a similar gene deregulation signature than inactivation of the decapping complex. Finally, the combination of dne1 and dcp2 mutations revealed a functional redundancy between DNE1 and DCP2 in controlling phyllotactic pattern formation. Our work identifies DNE1, a hitherto unknown DCP1 protein partner highly conserved in the plant kingdom and identifies its importance for developmental robustness.
Roche Béatrice, Garcia-Rivera Mariel A, Normant Vincent, Kuhn Lauriane, Hammann Philippe, Brönstrup Mark, Mislin Gaëtan L A, Schalk Isabelle J
A role for PchHI as the ABC transporter in iron acquisition by the siderophore pyochelin in Pseudomonas aeruginosa Article de journal
Dans: Environ Microbiol, vol. 24, no. 2, p. 866–877, 2022, ISSN: 1462-2920.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{pmid34664350,
title = {A role for PchHI as the ABC transporter in iron acquisition by the siderophore pyochelin in Pseudomonas aeruginosa},
author = {Béatrice Roche and Mariel A Garcia-Rivera and Vincent Normant and Lauriane Kuhn and Philippe Hammann and Mark Brönstrup and Gaëtan L A Mislin and Isabelle J Schalk},
doi = {10.1111/1462-2920.15811},
issn = {1462-2920},
year = {2022},
date = {2022-02-01},
journal = {Environ Microbiol},
volume = {24},
number = {2},
pages = {866--877},
abstract = {Iron is an essential nutrient for bacterial growth but poorly bioavailable. Bacteria scavenge ferric iron by synthesizing and secreting siderophores, small compounds with a high affinity for iron. Pyochelin (PCH) is one of the two siderophores produced by the opportunistic pathogen Pseudomonas aeruginosa. After capturing a ferric iron molecule, PCH-Fe is imported back into bacteria first by the outer membrane transporter FptA and then by the inner membrane permease FptX. Here, using molecular biology, Fe uptake assays, and LC-MS/MS quantification, we first find a role for PchHI as the heterodimeric ABC transporter involved in the siderophore-free iron uptake into the bacterial cytoplasm. We also provide the first evidence that PCH is able to reach the bacterial periplasm and cytoplasm when both FptA and FptX are expressed. Finally, we detected an interaction between PchH and FptX, linking the ABC transporter PchHI with the inner permease FptX in the PCH-Fe uptake pathway. These results pave the way for a better understanding of the PCH siderophore pathway, giving future directions to tackle P. aeruginosa infections.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
Iron is an essential nutrient for bacterial growth but poorly bioavailable. Bacteria scavenge ferric iron by synthesizing and secreting siderophores, small compounds with a high affinity for iron. Pyochelin (PCH) is one of the two siderophores produced by the opportunistic pathogen Pseudomonas aeruginosa. After capturing a ferric iron molecule, PCH-Fe is imported back into bacteria first by the outer membrane transporter FptA and then by the inner membrane permease FptX. Here, using molecular biology, Fe uptake assays, and LC-MS/MS quantification, we first find a role for PchHI as the heterodimeric ABC transporter involved in the siderophore-free iron uptake into the bacterial cytoplasm. We also provide the first evidence that PCH is able to reach the bacterial periplasm and cytoplasm when both FptA and FptX are expressed. Finally, we detected an interaction between PchH and FptX, linking the ABC transporter PchHI with the inner permease FptX in the PCH-Fe uptake pathway. These results pave the way for a better understanding of the PCH siderophore pathway, giving future directions to tackle P. aeruginosa infections.
Perraud Quentin, Kuhn Lauriane, Fritsch Sarah, Graulier Gwenaëlle, Gasser Véronique, Normant Vincent, Hammann Philippe, Schalk Isabelle J
Opportunistic use of catecholamine neurotransmitters as siderophores to access iron by Pseudomonas aeruginosa Article de journal
Dans: Environ Microbiol, vol. 24, no. 2, p. 878–893, 2022, ISSN: 1462-2920.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{pmid33350053,
title = {Opportunistic use of catecholamine neurotransmitters as siderophores to access iron by Pseudomonas aeruginosa},
author = {Quentin Perraud and Lauriane Kuhn and Sarah Fritsch and Gwenaëlle Graulier and Véronique Gasser and Vincent Normant and Philippe Hammann and Isabelle J Schalk},
doi = {10.1111/1462-2920.15372},
issn = {1462-2920},
year = {2022},
date = {2022-02-01},
journal = {Environ Microbiol},
volume = {24},
number = {2},
pages = {878--893},
abstract = {Iron is an essential nutrient for bacterial growth and the cause of a fierce battle between the pathogen and host during infection. Bacteria have developed several strategies to access iron from the host, the most common being the production of siderophores, small iron-chelating molecules secreted into the bacterial environment. The opportunist pathogen Pseudomonas aeruginosa produces two siderophores, pyoverdine and pyochelin, and is also able to use a wide panoply of xenosiderophores, siderophores produced by other microorganisms. Here, we demonstrate that catecholamine neurotransmitters (dopamine, l-DOPA, epinephrine and norepinephrine) are able to chelate iron and efficiently bring iron into P. aeruginosa cells via TonB-dependent transporters (TBDTs). Bacterial growth assays under strong iron-restricted conditions and with numerous mutants showed that the TBDTs involved are PiuA and PirA. PiuA exhibited more pronounced specificity for dopamine uptake than for norepinephrine, epinephrine and l-DOPA, whereas PirA specificity appeared to be higher for l-DOPA and norepinephrine. Proteomic and qRT-PCR approaches showed pirA transcription and expression to be induced in the presence of all four catecholamines. Finally, the oxidative properties of catecholamines enable them to reduce iron, and we observed ferrous iron uptake via the FeoABC system in the presence of l-DOPA.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
Iron is an essential nutrient for bacterial growth and the cause of a fierce battle between the pathogen and host during infection. Bacteria have developed several strategies to access iron from the host, the most common being the production of siderophores, small iron-chelating molecules secreted into the bacterial environment. The opportunist pathogen Pseudomonas aeruginosa produces two siderophores, pyoverdine and pyochelin, and is also able to use a wide panoply of xenosiderophores, siderophores produced by other microorganisms. Here, we demonstrate that catecholamine neurotransmitters (dopamine, l-DOPA, epinephrine and norepinephrine) are able to chelate iron and efficiently bring iron into P. aeruginosa cells via TonB-dependent transporters (TBDTs). Bacterial growth assays under strong iron-restricted conditions and with numerous mutants showed that the TBDTs involved are PiuA and PirA. PiuA exhibited more pronounced specificity for dopamine uptake than for norepinephrine, epinephrine and l-DOPA, whereas PirA specificity appeared to be higher for l-DOPA and norepinephrine. Proteomic and qRT-PCR approaches showed pirA transcription and expression to be induced in the presence of all four catecholamines. Finally, the oxidative properties of catecholamines enable them to reduce iron, and we observed ferrous iron uptake via the FeoABC system in the presence of l-DOPA.
Normant Vincent, Kuhn Lauriane, Munier Mathilde, Hammann Philippe, Mislin Gaëtan L. A., Schalk Isabelle J.
How the Presence of Hemin Affects the Expression of the Different Iron Uptake Pathways in Pseudomonas aeruginosa Cells Article de journal
Dans: ACS infectious diseases, vol. 8, no. 1, p. 183–196, 2022, ISSN: 2373-8227.
Résumé | Liens | BibTeX | Étiquettes: Hemin, hemin (heme) uptake, Iron, iron homeostasis, iron uptake, outer membrane transporters, PPSE, proteomics, Pseudomonas aeruginosa, siderophore, Siderophores
@article{normant_how_2022,
title = {How the Presence of Hemin Affects the Expression of the Different Iron Uptake Pathways in Pseudomonas aeruginosa Cells},
author = {Vincent Normant and Lauriane Kuhn and Mathilde Munier and Philippe Hammann and Gaëtan L. A. Mislin and Isabelle J. Schalk},
doi = {10.1021/acsinfecdis.1c00525},
issn = {2373-8227},
year = {2022},
date = {2022-01-01},
journal = {ACS infectious diseases},
volume = {8},
number = {1},
pages = {183--196},
abstract = {Iron is an essential nutriment for almost all organisms, but this metal is poorly bioavailable. During infection, bacteria access iron from the host by importing either iron or heme. Pseudomonas aeruginosa, a gram-negative pathogen, secretes two siderophores, pyoverdine (PVD) and pyochelin (PCH), to access iron and is also able to use many siderophores produced by other microorganisms (called xenosiderophores). To access heme, P. aeruginosa uses three distinct uptake pathways, named Has, Phu, and Hxu. We previously showed that P. aeruginosa expresses the Has and Phu heme uptake systems and the PVD- and PCH-dependent iron uptake pathways in iron-restricted growth conditions, using proteomic and RT-qPCR approaches. Here, using the same approaches, we show that physiological concentrations of hemin in the bacterial growth medium result in the repression of the expression of the proteins of the PVD- and PCH-dependent iron uptake pathways, leading to less production of these two siderophores. This indicates that the pathogen adapts its phenotype to use hemin as an iron source rather than produce PVD and PCH to access iron. Moreover, the presence of both hemin and a xenosiderophore resulted in (i) the strong induction of the expression of the proteins of the added xenosiderophore uptake pathway, (ii) repression of the PVD- and PCH-dependent iron uptake pathways, and (iii) no effect on the expression levels of the Has, Phu, or Hxu systems, indicating that bacteria use both xenosiderophores and heme to access iron.},
keywords = {Hemin, hemin (heme) uptake, Iron, iron homeostasis, iron uptake, outer membrane transporters, PPSE, proteomics, Pseudomonas aeruginosa, siderophore, Siderophores},
pubstate = {published},
tppubtype = {article}
}
Iron is an essential nutriment for almost all organisms, but this metal is poorly bioavailable. During infection, bacteria access iron from the host by importing either iron or heme. Pseudomonas aeruginosa, a gram-negative pathogen, secretes two siderophores, pyoverdine (PVD) and pyochelin (PCH), to access iron and is also able to use many siderophores produced by other microorganisms (called xenosiderophores). To access heme, P. aeruginosa uses three distinct uptake pathways, named Has, Phu, and Hxu. We previously showed that P. aeruginosa expresses the Has and Phu heme uptake systems and the PVD- and PCH-dependent iron uptake pathways in iron-restricted growth conditions, using proteomic and RT-qPCR approaches. Here, using the same approaches, we show that physiological concentrations of hemin in the bacterial growth medium result in the repression of the expression of the proteins of the PVD- and PCH-dependent iron uptake pathways, leading to less production of these two siderophores. This indicates that the pathogen adapts its phenotype to use hemin as an iron source rather than produce PVD and PCH to access iron. Moreover, the presence of both hemin and a xenosiderophore resulted in (i) the strong induction of the expression of the proteins of the added xenosiderophore uptake pathway, (ii) repression of the PVD- and PCH-dependent iron uptake pathways, and (iii) no effect on the expression levels of the Has, Phu, or Hxu systems, indicating that bacteria use both xenosiderophores and heme to access iron.
Hémono Mickaële, Haller Alexandre, Chicher Johana, Duchêne Anne-Marie, Ngondo Richard Patryk
The interactome of CLUH reveals its association to SPAG5 and its co-translational proximity to mitochondrial proteins Article de journal
Dans: BMC Biol, vol. 20, no. 1, p. 13, 2022, ISSN: 1741-7007.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{pmid35012549b,
title = {The interactome of CLUH reveals its association to SPAG5 and its co-translational proximity to mitochondrial proteins},
author = {Mickaële Hémono and Alexandre Haller and Johana Chicher and Anne-Marie Duchêne and Richard Patryk Ngondo},
doi = {10.1186/s12915-021-01213-y},
issn = {1741-7007},
year = {2022},
date = {2022-01-01},
urldate = {2022-01-01},
journal = {BMC Biol},
volume = {20},
number = {1},
pages = {13},
abstract = {BACKGROUND: Mitochondria require thousands of proteins to fulfill their essential function in energy production and other fundamental biological processes. These proteins are mostly encoded by the nuclear genome, translated in the cytoplasm before being imported into the organelle. RNA binding proteins (RBPs) are central players in the regulation of this process by affecting mRNA translation, stability, or localization. CLUH is an RBP recognizing specifically mRNAs coding for mitochondrial proteins, but its precise molecular function and interacting partners remain undiscovered in mammals.
RESULTS: Here we reveal for the first time CLUH interactome in mammalian cells. Using both co-IP and BioID proximity-labeling approaches, we identify novel molecular partners interacting stably or transiently with CLUH in HCT116 cells and mouse embryonic stem cells. We reveal stable RNA-independent interactions of CLUH with itself and with SPAG5 in cytosolic granular structures. More importantly, we uncover an unexpected proximity of CLUH to mitochondrial proteins and their cognate mRNAs in the cytosol. We show that this interaction occurs during the process of active translation and is dependent on CLUH TPR domain.
CONCLUSIONS: Overall, through the analysis of CLUH interactome, our study sheds a new light on CLUH molecular function by revealing new partners and by highlighting its link to the translation and subcellular localization of some mRNAs coding for mitochondrial proteins.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
BACKGROUND: Mitochondria require thousands of proteins to fulfill their essential function in energy production and other fundamental biological processes. These proteins are mostly encoded by the nuclear genome, translated in the cytoplasm before being imported into the organelle. RNA binding proteins (RBPs) are central players in the regulation of this process by affecting mRNA translation, stability, or localization. CLUH is an RBP recognizing specifically mRNAs coding for mitochondrial proteins, but its precise molecular function and interacting partners remain undiscovered in mammals.
RESULTS: Here we reveal for the first time CLUH interactome in mammalian cells. Using both co-IP and BioID proximity-labeling approaches, we identify novel molecular partners interacting stably or transiently with CLUH in HCT116 cells and mouse embryonic stem cells. We reveal stable RNA-independent interactions of CLUH with itself and with SPAG5 in cytosolic granular structures. More importantly, we uncover an unexpected proximity of CLUH to mitochondrial proteins and their cognate mRNAs in the cytosol. We show that this interaction occurs during the process of active translation and is dependent on CLUH TPR domain.
CONCLUSIONS: Overall, through the analysis of CLUH interactome, our study sheds a new light on CLUH molecular function by revealing new partners and by highlighting its link to the translation and subcellular localization of some mRNAs coding for mitochondrial proteins.
RESULTS: Here we reveal for the first time CLUH interactome in mammalian cells. Using both co-IP and BioID proximity-labeling approaches, we identify novel molecular partners interacting stably or transiently with CLUH in HCT116 cells and mouse embryonic stem cells. We reveal stable RNA-independent interactions of CLUH with itself and with SPAG5 in cytosolic granular structures. More importantly, we uncover an unexpected proximity of CLUH to mitochondrial proteins and their cognate mRNAs in the cytosol. We show that this interaction occurs during the process of active translation and is dependent on CLUH TPR domain.
CONCLUSIONS: Overall, through the analysis of CLUH interactome, our study sheds a new light on CLUH molecular function by revealing new partners and by highlighting its link to the translation and subcellular localization of some mRNAs coding for mitochondrial proteins.
Ponce J. R. Jaramillo, Kapps D., Paulus C., Chicher J., Frugier M.
Discovery of two distinct aminoacyl-tRNA synthetase complexes anchored to the Plasmodium surface tRNA import protein Article de journal
Dans: J Biol Chem, vol. 298, iss. 6, p. 101987, 2022, ISBN: 35487244, (1083-351X (Electronic) 0021-9258 (Linking) Journal Article).
Résumé | Liens | BibTeX | Étiquettes: FRUGIER, Labex, PPSE, Unité ARN
@article{nokey,
title = {Discovery of two distinct aminoacyl-tRNA synthetase complexes anchored to the Plasmodium surface tRNA import protein},
author = {J. R. Jaramillo Ponce and D. Kapps and C. Paulus and J. Chicher and M. Frugier},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=35487244},
doi = {0.1016/j.jbc.2022.101987},
isbn = {35487244},
year = {2022},
date = {2022-01-01},
urldate = {2022-01-01},
journal = {J Biol Chem},
volume = {298},
issue = {6},
pages = {101987},
abstract = {Aminoacyl-tRNA synthetases (aaRSs) attach amino acids to their cognate transfer RNAs. In eukaryotes, a subset of cytosolic aaRSs is organized into a multi-synthetase complex (MSC), along with specialized scaffolding proteins referred to as aaRS-interacting multifunctional proteins (AIMPs). In Plasmodium, the causative agent of malaria, the tRNA import protein (tRip), is a membrane protein that has been shown to participate in tRNA trafficking; here, we show that tRip also functions as an AIMP. We identified three aaRSs, namely the glutamyl- (ERS), glutaminyl- (QRS), and methionyl- (MRS) tRNA synthetases, which were specifically co-immunoprecipitated with tRip in P. berghei blood stage parasites. All four proteins contain an N-terminal GST-like domain that was demonstrated to be involved in MSC assembly. In contrast to previous studies, further dissection of GST-like interactions identified two exclusive heterotrimeric complexes: the Q-complex (tRip:ERS:QRS) and the M-complex (tRip:ERS:MRS). Gel filtration and light scattering suggest a 2:2:2 stoichiometry for both complexes but with distinct biophysical properties, and mutational analysis further revealed that the GST-like domains of QRS and MRS use different strategies to bind ERS. Taken together our results demonstrate that neither the singular homodimerization of tRip, nor its localization in the parasite plasma membrane prevents the formation of MSCs in Plasmodium. Besides, the extracellular localization of the tRNA-binding module of tRip is compensated by the presence of additional tRNA-binding modules fused to MRS and QRS, providing each MSC with two spatially distinct functions: aminoacylation of intraparasitic tRNAs and binding of extracellular tRNAs. This unique host-pathogen interaction is discussed.},
note = {1083-351X (Electronic)
0021-9258 (Linking)
Journal Article},
keywords = {FRUGIER, Labex, PPSE, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
Aminoacyl-tRNA synthetases (aaRSs) attach amino acids to their cognate transfer RNAs. In eukaryotes, a subset of cytosolic aaRSs is organized into a multi-synthetase complex (MSC), along with specialized scaffolding proteins referred to as aaRS-interacting multifunctional proteins (AIMPs). In Plasmodium, the causative agent of malaria, the tRNA import protein (tRip), is a membrane protein that has been shown to participate in tRNA trafficking; here, we show that tRip also functions as an AIMP. We identified three aaRSs, namely the glutamyl- (ERS), glutaminyl- (QRS), and methionyl- (MRS) tRNA synthetases, which were specifically co-immunoprecipitated with tRip in P. berghei blood stage parasites. All four proteins contain an N-terminal GST-like domain that was demonstrated to be involved in MSC assembly. In contrast to previous studies, further dissection of GST-like interactions identified two exclusive heterotrimeric complexes: the Q-complex (tRip:ERS:QRS) and the M-complex (tRip:ERS:MRS). Gel filtration and light scattering suggest a 2:2:2 stoichiometry for both complexes but with distinct biophysical properties, and mutational analysis further revealed that the GST-like domains of QRS and MRS use different strategies to bind ERS. Taken together our results demonstrate that neither the singular homodimerization of tRip, nor its localization in the parasite plasma membrane prevents the formation of MSCs in Plasmodium. Besides, the extracellular localization of the tRNA-binding module of tRip is compensated by the presence of additional tRNA-binding modules fused to MRS and QRS, providing each MSC with two spatially distinct functions: aminoacylation of intraparasitic tRNAs and binding of extracellular tRNAs. This unique host-pathogen interaction is discussed.
Normant Vincent, Kuhn Lauriane, Munier Mathilde, Hammann Philippe, Mislin Gaëtan L A, Schalk Isabelle J
How the Presence of Hemin Affects the Expression of the Different Iron Uptake Pathways in Cells Article de journal
Dans: ACS Infect Dis, vol. 8, no. 1, p. 183–196, 2022, ISSN: 2373-8227.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{pmid34878758,
title = {How the Presence of Hemin Affects the Expression of the Different Iron Uptake Pathways in Cells},
author = {Vincent Normant and Lauriane Kuhn and Mathilde Munier and Philippe Hammann and Gaëtan L A Mislin and Isabelle J Schalk},
doi = {10.1021/acsinfecdis.1c00525},
issn = {2373-8227},
year = {2022},
date = {2022-01-01},
journal = {ACS Infect Dis},
volume = {8},
number = {1},
pages = {183--196},
abstract = {Iron is an essential nutriment for almost all organisms, but this metal is poorly bioavailable. During infection, bacteria access iron from the host by importing either iron or heme. , a gram-negative pathogen, secretes two siderophores, pyoverdine (PVD) and pyochelin (PCH), to access iron and is also able to use many siderophores produced by other microorganisms (called xenosiderophores). To access heme, uses three distinct uptake pathways, named Has, Phu, and Hxu. We previously showed that expresses the Has and Phu heme uptake systems and the PVD- and PCH-dependent iron uptake pathways in iron-restricted growth conditions, using proteomic and RT-qPCR approaches. Here, using the same approaches, we show that physiological concentrations of hemin in the bacterial growth medium result in the repression of the expression of the proteins of the PVD- and PCH-dependent iron uptake pathways, leading to less production of these two siderophores. This indicates that the pathogen adapts its phenotype to use hemin as an iron source rather than produce PVD and PCH to access iron. Moreover, the presence of both hemin and a xenosiderophore resulted in (i) the strong induction of the expression of the proteins of the added xenosiderophore uptake pathway, (ii) repression of the PVD- and PCH-dependent iron uptake pathways, and (iii) no effect on the expression levels of the Has, Phu, or Hxu systems, indicating that bacteria use both xenosiderophores and heme to access iron.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
Iron is an essential nutriment for almost all organisms, but this metal is poorly bioavailable. During infection, bacteria access iron from the host by importing either iron or heme. , a gram-negative pathogen, secretes two siderophores, pyoverdine (PVD) and pyochelin (PCH), to access iron and is also able to use many siderophores produced by other microorganisms (called xenosiderophores). To access heme, uses three distinct uptake pathways, named Has, Phu, and Hxu. We previously showed that expresses the Has and Phu heme uptake systems and the PVD- and PCH-dependent iron uptake pathways in iron-restricted growth conditions, using proteomic and RT-qPCR approaches. Here, using the same approaches, we show that physiological concentrations of hemin in the bacterial growth medium result in the repression of the expression of the proteins of the PVD- and PCH-dependent iron uptake pathways, leading to less production of these two siderophores. This indicates that the pathogen adapts its phenotype to use hemin as an iron source rather than produce PVD and PCH to access iron. Moreover, the presence of both hemin and a xenosiderophore resulted in (i) the strong induction of the expression of the proteins of the added xenosiderophore uptake pathway, (ii) repression of the PVD- and PCH-dependent iron uptake pathways, and (iii) no effect on the expression levels of the Has, Phu, or Hxu systems, indicating that bacteria use both xenosiderophores and heme to access iron.
2021
Waltz Florent, Salinas-Giegé Thalia, Englmeier Robert, Meichel Herrade, Soufari Heddy, Kuhn Lauriane, Pfeffer Stefan, Förster Friedrich, Engel Benjamin D., Giegé Philippe, Drouard Laurence, Hashem Yaser
How to build a ribosome from RNA fragments in Chlamydomonas mitochondria Article de journal
Dans: Nature Communications, vol. 12, no. 1, p. 7176, 2021, ISSN: 2041-1723.
Résumé | Liens | BibTeX | Étiquettes: Chlamydomonas reinhardtii, Cryoelectron Microscopy, mitochondria, Mitochondrial Proteins, Mitochondrial Ribosomes, PPSE, Ribosomal Proteins, ribosomes, RNA
@article{waltz_how_2021,
title = {How to build a ribosome from RNA fragments in Chlamydomonas mitochondria},
author = {Florent Waltz and Thalia Salinas-Giegé and Robert Englmeier and Herrade Meichel and Heddy Soufari and Lauriane Kuhn and Stefan Pfeffer and Friedrich Förster and Benjamin D. Engel and Philippe Giegé and Laurence Drouard and Yaser Hashem},
doi = {10.1038/s41467-021-27200-z},
issn = {2041-1723},
year = {2021},
date = {2021-12-01},
journal = {Nature Communications},
volume = {12},
number = {1},
pages = {7176},
abstract = {Mitochondria are the powerhouse of eukaryotic cells. They possess their own gene expression machineries where highly divergent and specialized ribosomes, named hereafter mitoribosomes, translate the few essential messenger RNAs still encoded by mitochondrial genomes. Here, we present a biochemical and structural characterization of the mitoribosome in the model green alga Chlamydomonas reinhardtii, as well as a functional study of some of its specific components. Single particle cryo-electron microscopy resolves how the Chlamydomonas mitoribosome is assembled from 13 rRNA fragments encoded by separate non-contiguous gene pieces. Additional proteins, mainly OPR, PPR and mTERF helical repeat proteins, are found in Chlamydomonas mitoribosome, revealing the structure of an OPR protein in complex with its RNA binding partner. Targeted amiRNA silencing indicates that these ribosomal proteins are required for mitoribosome integrity. Finally, we use cryo-electron tomography to show that Chlamydomonas mitoribosomes are attached to the inner mitochondrial membrane via two contact points mediated by Chlamydomonas-specific proteins. Our study expands our understanding of mitoribosome diversity and the various strategies these specialized molecular machines adopt for membrane tethering.},
keywords = {Chlamydomonas reinhardtii, Cryoelectron Microscopy, mitochondria, Mitochondrial Proteins, Mitochondrial Ribosomes, PPSE, Ribosomal Proteins, ribosomes, RNA},
pubstate = {published},
tppubtype = {article}
}
Mitochondria are the powerhouse of eukaryotic cells. They possess their own gene expression machineries where highly divergent and specialized ribosomes, named hereafter mitoribosomes, translate the few essential messenger RNAs still encoded by mitochondrial genomes. Here, we present a biochemical and structural characterization of the mitoribosome in the model green alga Chlamydomonas reinhardtii, as well as a functional study of some of its specific components. Single particle cryo-electron microscopy resolves how the Chlamydomonas mitoribosome is assembled from 13 rRNA fragments encoded by separate non-contiguous gene pieces. Additional proteins, mainly OPR, PPR and mTERF helical repeat proteins, are found in Chlamydomonas mitoribosome, revealing the structure of an OPR protein in complex with its RNA binding partner. Targeted amiRNA silencing indicates that these ribosomal proteins are required for mitoribosome integrity. Finally, we use cryo-electron tomography to show that Chlamydomonas mitoribosomes are attached to the inner mitochondrial membrane via two contact points mediated by Chlamydomonas-specific proteins. Our study expands our understanding of mitoribosome diversity and the various strategies these specialized molecular machines adopt for membrane tethering.
Schiaffini Marlene, Chicois Clara, Pouclet Aude, Chartier Tiphaine, Ubrig Elodie, Gobert Anthony, Zuber Hélène, Mutterer Jérôme, Chicher Johana, Kuhn Lauriane, Hammann Philippe, Gagliardi Dominique, Garcia Damien
A NYN domain protein directly interacts with DECAPPING1 and is required for phyllotactic pattern Article de journal
Dans: Plant Physiology, p. kiab529, 2021, ISSN: 1532-2548.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{schiaffini_nyn_2021,
title = {A NYN domain protein directly interacts with DECAPPING1 and is required for phyllotactic pattern},
author = {Marlene Schiaffini and Clara Chicois and Aude Pouclet and Tiphaine Chartier and Elodie Ubrig and Anthony Gobert and Hélène Zuber and Jérôme Mutterer and Johana Chicher and Lauriane Kuhn and Philippe Hammann and Dominique Gagliardi and Damien Garcia},
doi = {10.1093/plphys/kiab529},
issn = {1532-2548},
year = {2021},
date = {2021-11-01},
urldate = {2021-11-01},
journal = {Plant Physiology},
pages = {kiab529},
abstract = {In eukaryotes, general mRNA decay requires the decapping complex. The activity of this complex depends on its catalytic subunit, DECAPPING2 (DCP2), and its interaction with decapping enhancers, including its main partner DECAPPING1 (DCP1). Here, we report that in Arabidopsis thaliana, DCP1 also interacts with a NYN domain endoribonuclease, hence named DCP1-ASSOCIATED NYN ENDORIBONUCLEASE 1 (DNE1). Interestingly, we found DNE1 predominantly associated with DCP1, but not with DCP2, and reciprocally, suggesting the existence of two distinct protein complexes. We also showed that the catalytic residues of DNE1 are required to repress the expression of mRNAs in planta upon transient expression. The overexpression of DNE1 in transgenic lines led to growth defects and a similar gene deregulation signature than inactivation of the decapping complex. Finally, the combination of dne1 and dcp2 mutations revealed a functional redundancy between DNE1 and DCP2 in controlling phyllotactic pattern formation. Our work identifies DNE1, a hitherto unknown DCP1 protein partner highly conserved in the plant kingdom and identifies its importance for developmental robustness.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
In eukaryotes, general mRNA decay requires the decapping complex. The activity of this complex depends on its catalytic subunit, DECAPPING2 (DCP2), and its interaction with decapping enhancers, including its main partner DECAPPING1 (DCP1). Here, we report that in Arabidopsis thaliana, DCP1 also interacts with a NYN domain endoribonuclease, hence named DCP1-ASSOCIATED NYN ENDORIBONUCLEASE 1 (DNE1). Interestingly, we found DNE1 predominantly associated with DCP1, but not with DCP2, and reciprocally, suggesting the existence of two distinct protein complexes. We also showed that the catalytic residues of DNE1 are required to repress the expression of mRNAs in planta upon transient expression. The overexpression of DNE1 in transgenic lines led to growth defects and a similar gene deregulation signature than inactivation of the decapping complex. Finally, the combination of dne1 and dcp2 mutations revealed a functional redundancy between DNE1 and DCP2 in controlling phyllotactic pattern formation. Our work identifies DNE1, a hitherto unknown DCP1 protein partner highly conserved in the plant kingdom and identifies its importance for developmental robustness.
Incarbone Marco, Clavel Marion, Monsion Baptiste, Kuhn Lauriane, Scheer Hélène, Vantard Émilie, Poignavent Vianney, Dunoyer Patrice, Genschik Pascal, Ritzenthaler Christophe
Dans: The Plant Cell, vol. 33, no. 11, p. 3402–3420, 2021, ISSN: 1532-298X.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{incarbone_immunocapture_2021,
title = {Immunocapture of dsRNA-bound proteins provides insight into Tobacco rattle virus replication complexes and reveals Arabidopsis DRB2 to be a wide-spectrum antiviral effector},
author = {Marco Incarbone and Marion Clavel and Baptiste Monsion and Lauriane Kuhn and Hélène Scheer and Émilie Vantard and Vianney Poignavent and Patrice Dunoyer and Pascal Genschik and Christophe Ritzenthaler},
doi = {10.1093/plcell/koab214},
issn = {1532-298X},
year = {2021},
date = {2021-11-01},
journal = {The Plant Cell},
volume = {33},
number = {11},
pages = {3402--3420},
abstract = {Plant RNA viruses form organized membrane-bound replication complexes to replicate their genomes. This process requires virus- and host-encoded proteins and leads to the production of double-stranded RNA (dsRNA) replication intermediates. Here, we describe the use of Arabidopsis thaliana expressing GFP-tagged dsRNA-binding protein (B2:GFP) to pull down dsRNA and associated proteins in planta upon infection with Tobacco rattle virus (TRV). Mass spectrometry analysis of the dsRNA-B2:GFP-bound proteins from infected plants revealed the presence of viral proteins and numerous host proteins. Among a selection of nine host candidate proteins, eight showed relocalization upon infection, and seven of these colocalized with B2-labeled TRV replication complexes. Infection of A. thaliana T-DNA mutant lines for eight such factors revealed that genetic knockout of dsRNA-BINDING PROTEIN 2 (DRB2) leads to increased TRV accumulation and DRB2 overexpression caused a decrease in the accumulation of four different plant RNA viruses, indicating that DRB2 has a potent and wide-ranging antiviral activity. We propose B2:GFP-mediated pull down of dsRNA to be a versatile method to explore virus replication complex proteomes and to discover key host virus replication factors. Given the universality of dsRNA, development of this tool holds great potential to investigate RNA viruses in other host organisms.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
Plant RNA viruses form organized membrane-bound replication complexes to replicate their genomes. This process requires virus- and host-encoded proteins and leads to the production of double-stranded RNA (dsRNA) replication intermediates. Here, we describe the use of Arabidopsis thaliana expressing GFP-tagged dsRNA-binding protein (B2:GFP) to pull down dsRNA and associated proteins in planta upon infection with Tobacco rattle virus (TRV). Mass spectrometry analysis of the dsRNA-B2:GFP-bound proteins from infected plants revealed the presence of viral proteins and numerous host proteins. Among a selection of nine host candidate proteins, eight showed relocalization upon infection, and seven of these colocalized with B2-labeled TRV replication complexes. Infection of A. thaliana T-DNA mutant lines for eight such factors revealed that genetic knockout of dsRNA-BINDING PROTEIN 2 (DRB2) leads to increased TRV accumulation and DRB2 overexpression caused a decrease in the accumulation of four different plant RNA viruses, indicating that DRB2 has a potent and wide-ranging antiviral activity. We propose B2:GFP-mediated pull down of dsRNA to be a versatile method to explore virus replication complex proteomes and to discover key host virus replication factors. Given the universality of dsRNA, development of this tool holds great potential to investigate RNA viruses in other host organisms.
Roche Béatrice, Garcia-Rivera Mariel A., Normant Vincent, Kuhn Lauriane, Hammann Philippe, Brönstrup Mark, Mislin Gaëtan L. A., Schalk Isabelle J.
A role for PchHI as the ABC transporter in iron acquisition by the siderophore pyochelin in Pseudomonas aeruginosa Article de journal
Dans: Environmental Microbiology, 2021, ISSN: 1462-2920.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{roche_role_2021,
title = {A role for PchHI as the ABC transporter in iron acquisition by the siderophore pyochelin in Pseudomonas aeruginosa},
author = {Béatrice Roche and Mariel A. Garcia-Rivera and Vincent Normant and Lauriane Kuhn and Philippe Hammann and Mark Brönstrup and Gaëtan L. A. Mislin and Isabelle J. Schalk},
doi = {10.1111/1462-2920.15811},
issn = {1462-2920},
year = {2021},
date = {2021-10-01},
journal = {Environmental Microbiology},
abstract = {Iron is an essential nutrient for bacterial growth but poorly bioavailable. Bacteria scavenge ferric iron by synthesizing and secreting siderophores, small compounds with a high affinity for iron. Pyochelin (PCH) is one of the two siderophores produced by the opportunistic pathogen Pseudomonas aeruginosa. After capturing a ferric iron molecule, PCH-Fe is imported back into bacteria first by the outer membrane transporter FptA and then by the inner membrane permease FptX. Here, using molecular biology, 55 Fe uptake assays, and LC-MS/MS quantification, we first find a role for PchHI as the heterodimeric ABC transporter involved in the siderophore-free iron uptake into the bacterial cytoplasm. We also provide the first evidence that PCH is able to reach the bacterial periplasm and cytoplasm when both FptA and FptX are expressed. Finally, we detected an interaction between PchH and FptX, linking the ABC transporter PchHI with the inner permease FptX in the PCH-Fe uptake pathway. These results pave the way for a better understanding of the PCH siderophore pathway, giving future directions to tackle P. aeruginosa infections.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
Iron is an essential nutrient for bacterial growth but poorly bioavailable. Bacteria scavenge ferric iron by synthesizing and secreting siderophores, small compounds with a high affinity for iron. Pyochelin (PCH) is one of the two siderophores produced by the opportunistic pathogen Pseudomonas aeruginosa. After capturing a ferric iron molecule, PCH-Fe is imported back into bacteria first by the outer membrane transporter FptA and then by the inner membrane permease FptX. Here, using molecular biology, 55 Fe uptake assays, and LC-MS/MS quantification, we first find a role for PchHI as the heterodimeric ABC transporter involved in the siderophore-free iron uptake into the bacterial cytoplasm. We also provide the first evidence that PCH is able to reach the bacterial periplasm and cytoplasm when both FptA and FptX are expressed. Finally, we detected an interaction between PchH and FptX, linking the ABC transporter PchHI with the inner permease FptX in the PCH-Fe uptake pathway. These results pave the way for a better understanding of the PCH siderophore pathway, giving future directions to tackle P. aeruginosa infections.
Arquier Nathalie, Bjordal Marianne, Hammann Philippe, Kuhn Lauriane, Léopold Pierre
Brain adiponectin signaling controls peripheral insulin response in Drosophila Article de journal
Dans: Nature Communications, vol. 12, no. 1, p. 5633, 2021, ISSN: 2041-1723.
Résumé | Liens | BibTeX | Étiquettes: Adiponectin, Animals, Brain, Cell Line, Drosophila melanogaster, Drosophila Proteins, Energy Metabolism, Genetically Modified, Hemolymph, Homeostasis, Insulin, Juvenile Hormones, Larva, Neurons, PPSE, Receptors, Signal Transduction
@article{arquier_brain_2021,
title = {Brain adiponectin signaling controls peripheral insulin response in Drosophila},
author = {Nathalie Arquier and Marianne Bjordal and Philippe Hammann and Lauriane Kuhn and Pierre Léopold},
doi = {10.1038/s41467-021-25940-6},
issn = {2041-1723},
year = {2021},
date = {2021-09-01},
journal = {Nature Communications},
volume = {12},
number = {1},
pages = {5633},
abstract = {The brain plays a key role in energy homeostasis, detecting nutrients, metabolites and circulating hormones from peripheral organs and integrating this information to control food intake and energy expenditure. Here, we show that a group of neurons in the Drosophila larval brain expresses the adiponectin receptor (AdipoR) and controls systemic growth and metabolism through insulin signaling. We identify glucose-regulated protein 78 (Grp78) as a circulating antagonist of AdipoR function produced by fat cells in response to dietary sugar. We further show that central AdipoR signaling inhibits peripheral Juvenile Hormone (JH) response, promoting insulin signaling. In conclusion, we identify a neuroendocrine axis whereby AdipoR-positive neurons control systemic insulin response.},
keywords = {Adiponectin, Animals, Brain, Cell Line, Drosophila melanogaster, Drosophila Proteins, Energy Metabolism, Genetically Modified, Hemolymph, Homeostasis, Insulin, Juvenile Hormones, Larva, Neurons, PPSE, Receptors, Signal Transduction},
pubstate = {published},
tppubtype = {article}
}
The brain plays a key role in energy homeostasis, detecting nutrients, metabolites and circulating hormones from peripheral organs and integrating this information to control food intake and energy expenditure. Here, we show that a group of neurons in the Drosophila larval brain expresses the adiponectin receptor (AdipoR) and controls systemic growth and metabolism through insulin signaling. We identify glucose-regulated protein 78 (Grp78) as a circulating antagonist of AdipoR function produced by fat cells in response to dietary sugar. We further show that central AdipoR signaling inhibits peripheral Juvenile Hormone (JH) response, promoting insulin signaling. In conclusion, we identify a neuroendocrine axis whereby AdipoR-positive neurons control systemic insulin response.
Khong Minh-Thuong, Berl Valérie, Kuhn Lauriane, Hammann Philippe, Lepoittevin Jean-Pierre
Chemical Modifications Induced by Phthalic Anhydride, a Respiratory Sensitizer, in Reconstructed Human Epidermis: A Combined HRMAS NMR and LC-MS/MS Proteomic Approach Article de journal
Dans: Chemical Research in Toxicology, vol. 34, no. 9, p. 2087–2099, 2021, ISSN: 1520-5010.
Résumé | Liens | BibTeX | Étiquettes: PPSE
@article{khong_chemical_2021,
title = {Chemical Modifications Induced by Phthalic Anhydride, a Respiratory Sensitizer, in Reconstructed Human Epidermis: A Combined HRMAS NMR and LC-MS/MS Proteomic Approach},
author = {Minh-Thuong Khong and Valérie Berl and Lauriane Kuhn and Philippe Hammann and Jean-Pierre Lepoittevin},
doi = {10.1021/acs.chemrestox.1c00172},
issn = {1520-5010},
year = {2021},
date = {2021-09-01},
journal = {Chemical Research in Toxicology},
volume = {34},
number = {9},
pages = {2087--2099},
abstract = {Chemical skin and respiratory allergies are becoming a major health problem. To date our knowledge on the process of protein haptenation is still limited and mainly derived from studies performed in solution using model nucleophiles. In order to better understand chemical interactions between chemical allergens and the skin, we have investigated the reactivity of phthalic anhydride 1 (PA), a chemical respiratory sensitizer, toward reconstructed human epidermis (RHE). This study was performed using a new approach combining HRMAS NMR to investigate the in situ chemical reactivity and LC-MS/MS to identify modified epidermal proteins. In RHE, the reaction of PA appeared to be quite fast and the major product formed was phthalic acid. Two amide type adducts on lysine residues were observed and after 8h of incubation, we also observed the formation of an imide type cyclized adducts with lysine. In parallel, RHE samples topically exposed to phthalic anhydride (13C)-1 were analyzed using the shotgun proteomics method. Thus, 948 different proteins were extracted and identified, 135 of which being modified by PA, i.e., 14.2% of the extracted proteome. A total of 211 amino acids were modified by PA and validated by fragmentation spectra. We thus identified 154 modified lysines, 22 modified histidines, 30 modified tyrosines, and 5 modified arginines. The rate of modified residues, as a proportion of the total number of modifiable nucleophilic residues in RHE, was rather low (1%). At the protein level, modified proteins were mainly type I and type II keratins and other proteins which are abundant in the epidermis such as protein S100A, Caspase 14, annexin A2, serpin B3, fatty-acid binding protein 5, histone H2, H3, H4, etc. However, the most modified protein, mainly on histidine residues, was filaggrin, a protein that is of low abundance (0.0266 mol %) and rich in histidine.},
keywords = {PPSE},
pubstate = {published},
tppubtype = {article}
}
Chemical skin and respiratory allergies are becoming a major health problem. To date our knowledge on the process of protein haptenation is still limited and mainly derived from studies performed in solution using model nucleophiles. In order to better understand chemical interactions between chemical allergens and the skin, we have investigated the reactivity of phthalic anhydride 1 (PA), a chemical respiratory sensitizer, toward reconstructed human epidermis (RHE). This study was performed using a new approach combining HRMAS NMR to investigate the in situ chemical reactivity and LC-MS/MS to identify modified epidermal proteins. In RHE, the reaction of PA appeared to be quite fast and the major product formed was phthalic acid. Two amide type adducts on lysine residues were observed and after 8h of incubation, we also observed the formation of an imide type cyclized adducts with lysine. In parallel, RHE samples topically exposed to phthalic anhydride (13C)-1 were analyzed using the shotgun proteomics method. Thus, 948 different proteins were extracted and identified, 135 of which being modified by PA, i.e., 14.2% of the extracted proteome. A total of 211 amino acids were modified by PA and validated by fragmentation spectra. We thus identified 154 modified lysines, 22 modified histidines, 30 modified tyrosines, and 5 modified arginines. The rate of modified residues, as a proportion of the total number of modifiable nucleophilic residues in RHE, was rather low (1%). At the protein level, modified proteins were mainly type I and type II keratins and other proteins which are abundant in the epidermis such as protein S100A, Caspase 14, annexin A2, serpin B3, fatty-acid binding protein 5, histone H2, H3, H4, etc. However, the most modified protein, mainly on histidine residues, was filaggrin, a protein that is of low abundance (0.0266 mol %) and rich in histidine.
Nettersheim Jo-Ann, Janel-Bintz Régine, Kuhn Lauriane, Cordonnier Agnès M.
DNA polymerase η is a substrate for calpain: a possible mechanism for pol η retention in UV-induced replication foci Article de journal
Dans: Journal of Cell Science, vol. 134, no. 13, p. jcs258637, 2021, ISSN: 1477-9137.
Résumé | Liens | BibTeX | Étiquettes: calpain, Calpain protease, CAPNS1, DNA Damage, DNA damage response, DNA polymerase η, DNA Repair, DNA Replication, DNA-Directed DNA Polymerase, PPSE, Replication foci, Translesion DNA synthesis
@article{nettersheim_dna_2021,
title = {DNA polymerase η is a substrate for calpain: a possible mechanism for pol η retention in UV-induced replication foci},
author = {Jo-Ann Nettersheim and Régine Janel-Bintz and Lauriane Kuhn and Agnès M. Cordonnier},
doi = {10.1242/jcs.258637},
issn = {1477-9137},
year = {2021},
date = {2021-07-01},
journal = {Journal of Cell Science},
volume = {134},
number = {13},
pages = {jcs258637},
abstract = {DNA polymerase η (pol η) is specifically required for translesion DNA synthesis across UV-induced DNA lesions. Recruitment of this error-prone DNA polymerase is tightly regulated during replication to avoid mutagenesis and perturbation of fork progression. Here, we report that pol η interacts with the calpain small subunit-1 (CAPNS1) in a yeast two-hybrid screening. This interaction is functional, as demonstrated by the ability of endogenous calpain to mediate calcium-dependent cleavage of pol η in cell-free extracts and in living cells treated with a calcium ionophore. The proteolysis of pol η was found to occur at position 465, leading to a catalytically active truncated protein containing the PCNA-interacting motif PIP1. Unexpectedly, cell treatment with the specific calpain inhibitor calpeptin resulted in a decreased extent of pol η foci after UV irradiation, indicating that calpain positively regulates pol η accumulation in replication foci.},
keywords = {calpain, Calpain protease, CAPNS1, DNA Damage, DNA damage response, DNA polymerase η, DNA Repair, DNA Replication, DNA-Directed DNA Polymerase, PPSE, Replication foci, Translesion DNA synthesis},
pubstate = {published},
tppubtype = {article}
}
DNA polymerase η (pol η) is specifically required for translesion DNA synthesis across UV-induced DNA lesions. Recruitment of this error-prone DNA polymerase is tightly regulated during replication to avoid mutagenesis and perturbation of fork progression. Here, we report that pol η interacts with the calpain small subunit-1 (CAPNS1) in a yeast two-hybrid screening. This interaction is functional, as demonstrated by the ability of endogenous calpain to mediate calcium-dependent cleavage of pol η in cell-free extracts and in living cells treated with a calcium ionophore. The proteolysis of pol η was found to occur at position 465, leading to a catalytically active truncated protein containing the PCNA-interacting motif PIP1. Unexpectedly, cell treatment with the specific calpain inhibitor calpeptin resulted in a decreased extent of pol η foci after UV irradiation, indicating that calpain positively regulates pol η accumulation in replication foci.
Mancera-Martínez Eder, Dong Yihan, Makarian Joelle, Srour Ola, Thiébeauld Odon, Jamsheer Muhammed, Chicher Johana, Hammann Philippe, Schepetilnikov Mikhail, Ryabova Lyubov A.
Phosphorylation of a reinitiation supporting protein, RISP, determines its function in translation reinitiation Article de journal
Dans: Nucleic Acids Research, vol. 49, no. 12, p. 6908–6924, 2021, ISSN: 1362-4962.
Résumé | Liens | BibTeX | Étiquettes: Arabidopsis, Arabidopsis Proteins, Caulimovirus, Eukaryotic, Eukaryotic Initiation Factor-2B, Eukaryotic Initiation Factor-3, Large, Peptide Chain Initiation, Phosphorylation, PPSE, Ribosomal Protein S6, Ribosome Subunits, translational
@article{mancera-martinez_phosphorylation_2021,
title = {Phosphorylation of a reinitiation supporting protein, RISP, determines its function in translation reinitiation},
author = {Eder Mancera-Martínez and Yihan Dong and Joelle Makarian and Ola Srour and Odon Thiébeauld and Muhammed Jamsheer and Johana Chicher and Philippe Hammann and Mikhail Schepetilnikov and Lyubov A. Ryabova},
doi = {10.1093/nar/gkab501},
issn = {1362-4962},
year = {2021},
date = {2021-07-01},
journal = {Nucleic Acids Research},
volume = {49},
number = {12},
pages = {6908--6924},
abstract = {Reinitiation supporting protein, RISP, interacts with 60S (60S ribosomal subunit) and eIF3 (eukaryotic initiation factor 3) in plants. TOR (target-of-rapamycin) mediates RISP phosphorylation at residue Ser267, favoring its binding to eL24 (60S ribosomal protein L24). In a viral context, RISP, when phosphorylated, binds the CaMV transactivator/ viroplasmin, TAV, to assist in an exceptional mechanism of reinitiation after long ORF translation. Moreover, we show here that RISP interacts with eIF2 via eIF2β and TOR downstream target 40S ribosomal protein eS6. A RISP phosphorylation knockout, RISP-S267A, binds preferentially eIF2β, and both form a ternary complex with eIF3a in vitro. Accordingly, transient overexpression in plant protoplasts of RISP-S267A, but not a RISP phosphorylation mimic, RISP-S267D, favors translation initiation. In contrast, RISP-S267D preferentially binds eS6, and, when bound to the C-terminus of eS6, can capture 60S in a highly specific manner in vitro, suggesting that it mediates 60S loading during reinitiation. Indeed, eS6-deficient plants are highly resistant to CaMV due to their reduced reinitiation capacity. Strikingly, an eS6 phosphomimic, when stably expressed in eS6-deficient plants, can fully restore the reinitiation deficiency of these plants in cellular and viral contexts. These results suggest that RISP function in translation (re)initiation is regulated by phosphorylation at Ser267.},
keywords = {Arabidopsis, Arabidopsis Proteins, Caulimovirus, Eukaryotic, Eukaryotic Initiation Factor-2B, Eukaryotic Initiation Factor-3, Large, Peptide Chain Initiation, Phosphorylation, PPSE, Ribosomal Protein S6, Ribosome Subunits, translational},
pubstate = {published},
tppubtype = {article}
}
Reinitiation supporting protein, RISP, interacts with 60S (60S ribosomal subunit) and eIF3 (eukaryotic initiation factor 3) in plants. TOR (target-of-rapamycin) mediates RISP phosphorylation at residue Ser267, favoring its binding to eL24 (60S ribosomal protein L24). In a viral context, RISP, when phosphorylated, binds the CaMV transactivator/ viroplasmin, TAV, to assist in an exceptional mechanism of reinitiation after long ORF translation. Moreover, we show here that RISP interacts with eIF2 via eIF2β and TOR downstream target 40S ribosomal protein eS6. A RISP phosphorylation knockout, RISP-S267A, binds preferentially eIF2β, and both form a ternary complex with eIF3a in vitro. Accordingly, transient overexpression in plant protoplasts of RISP-S267A, but not a RISP phosphorylation mimic, RISP-S267D, favors translation initiation. In contrast, RISP-S267D preferentially binds eS6, and, when bound to the C-terminus of eS6, can capture 60S in a highly specific manner in vitro, suggesting that it mediates 60S loading during reinitiation. Indeed, eS6-deficient plants are highly resistant to CaMV due to their reduced reinitiation capacity. Strikingly, an eS6 phosphomimic, when stably expressed in eS6-deficient plants, can fully restore the reinitiation deficiency of these plants in cellular and viral contexts. These results suggest that RISP function in translation (re)initiation is regulated by phosphorylation at Ser267.
Dahlet Thomas, Truss Matthias, Frede Ute, Adhami Hala Al, Bardet Anaïs F., Dumas Michael, Vallet Judith, Chicher Johana, Hammann Philippe, Kottnik Sarah, Hansen Peter, Luz Uschi, Alvarez Gonzalo, Auclair Ghislain, Hecht Jochen, Robinson Peter N., Hagemeier Christian, Weber Michael
E2F6 initiates stable epigenetic silencing of germline genes during embryonic development Article de journal
Dans: Nature Communications, vol. 12, no. 1, p. 3582, 2021, ISSN: 2041-1723.