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2023
Klug Dennis, Gautier Amandine, Calvo Eric, Marois Eric, Blandin Stéphanie A.
The salivary protein Saglin facilitates efficient midgut colonization of Anopheles mosquitoes by malaria parasites Article de journal
Dans: Plos Pathogens, vol. 19, iss. 3, no. 3, 2023.
Résumé | Liens | BibTeX | Étiquettes: blandin, BLOOD, M3i, malarial parasites, marois, mosquitoes, Oocysts, Parasitic Diseases, Plasmodium, salivary glands, sporozoites
@article{Klug2023,
title = {The salivary protein Saglin facilitates efficient midgut colonization of Anopheles mosquitoes by malaria parasites},
author = {Dennis Klug and Amandine Gautier and Eric Calvo and Eric Marois and Stéphanie A. Blandin},
url = {https://doi.org/10.1371/journal.ppat.1010538},
doi = {10.1371/journal.ppat.1010538},
year = {2023},
date = {2023-03-02},
urldate = {2023-03-02},
booktitle = {Plos Pathogens},
journal = {Plos Pathogens},
volume = {19},
number = {3},
issue = {3},
abstract = {Female mosquitoes rely on blood feeding to acquire sufficient nutrients for egg development. Because of the importance of this process mosquitoes evolved salivary proteins with a broad range of functions acting as blood thinners, anti-coagulants and immunosuppressants. The effect of these proteins on the blood at the bite site directly influences the size of the blood bolus a female takes up in a given time frame. Both, time of feeding and bolus size, are important parameters for fecundity and survival. Recent studies have shown that a significant proportion of salivated proteins is re-ingested during feeding and becomes part of the blood meal. Here we investigated the salivary protein Saglin which has been previously suggested as putative receptor mediating malaria parasite entry into the salivary gland. By engineering a loss-of-function mutant in An. coluzzi we could show that the absence of Saglin impairs the development of parasite stages in the blood meal of the rodent malaria parasite P. berghei and the human malaria parasite P. falciparum lowering the parasite burden of subsequent stages and preventing efficient transmission at low infection densities. Furthermore, we could show that Saglin is present in the blood meal after feeding possibly indicating a previously overlooked parasite-vector interaction.},
keywords = {blandin, BLOOD, M3i, malarial parasites, marois, mosquitoes, Oocysts, Parasitic Diseases, Plasmodium, salivary glands, sporozoites},
pubstate = {published},
tppubtype = {article}
}
Female mosquitoes rely on blood feeding to acquire sufficient nutrients for egg development. Because of the importance of this process mosquitoes evolved salivary proteins with a broad range of functions acting as blood thinners, anti-coagulants and immunosuppressants. The effect of these proteins on the blood at the bite site directly influences the size of the blood bolus a female takes up in a given time frame. Both, time of feeding and bolus size, are important parameters for fecundity and survival. Recent studies have shown that a significant proportion of salivated proteins is re-ingested during feeding and becomes part of the blood meal. Here we investigated the salivary protein Saglin which has been previously suggested as putative receptor mediating malaria parasite entry into the salivary gland. By engineering a loss-of-function mutant in An. coluzzi we could show that the absence of Saglin impairs the development of parasite stages in the blood meal of the rodent malaria parasite P. berghei and the human malaria parasite P. falciparum lowering the parasite burden of subsequent stages and preventing efficient transmission at low infection densities. Furthermore, we could show that Saglin is present in the blood meal after feeding possibly indicating a previously overlooked parasite-vector interaction.
2017
Volohonsky Gloria, Hopp Ann-Katrin, Saenger Mélanie, Soichot Julien, Scholze Heidi, Boch Jens, Blandin Stéphanie A, Marois Eric
Transgenic Expression of the Anti-parasitic Factor TEP1 in the Malaria Mosquito Anopheles gambiae Article de journal
Dans: PLOS Pathogens, vol. 13, no. 1, p. e1006113, 2017, ISSN: 1553-7374.
Liens | BibTeX | Étiquettes: Anopheles gambiae, anti-parasitic factor, blandin, M3i, Malaria, marois, TEP1, transgenic
@article{volohonsky_transgenic_2017,
title = {Transgenic Expression of the Anti-parasitic Factor TEP1 in the Malaria Mosquito Anopheles gambiae},
author = {Gloria Volohonsky and Ann-Katrin Hopp and Mélanie Saenger and Julien Soichot and Heidi Scholze and Jens Boch and Stéphanie A Blandin and Eric Marois},
editor = {Kenneth D Vernick},
url = {http://dx.plos.org/10.1371/journal.ppat.1006113},
doi = {10.1371/journal.ppat.1006113},
issn = {1553-7374},
year = {2017},
date = {2017-01-01},
urldate = {2017-02-01},
journal = {PLOS Pathogens},
volume = {13},
number = {1},
pages = {e1006113},
keywords = {Anopheles gambiae, anti-parasitic factor, blandin, M3i, Malaria, marois, TEP1, transgenic},
pubstate = {published},
tppubtype = {article}
}
2016
Ehrhardt Katharina, Deregnaucourt Christiane, Goetz Alice-Anne, Tzanova Tzvetomira, Gallo Valentina, Arese Paolo, Pradines Bruno, Adjalley Sophie H, Bagrel Denyse, Blandin Stephanie A, Lanzer Michael, Davioud-Charvet Elisabeth
The redox-cycler plasmodione is a fast acting antimalarial lead compound with pronounced activity against sexual and early asexual blood-stage parasites Article de journal
Dans: Antimicrob. Agents Chemother., vol. 60, no. 9, p. 5146-5158, 2016, ISSN: 1098-6596.
Résumé | Liens | BibTeX | Étiquettes: antimalarial, blandin, M3i, parasites, Plasmodium, redox-cycler
@article{ehrhardt_redox-cycler_2016,
title = {The redox-cycler plasmodione is a fast acting antimalarial lead compound with pronounced activity against sexual and early asexual blood-stage parasites},
author = {Katharina Ehrhardt and Christiane Deregnaucourt and Alice-Anne Goetz and Tzvetomira Tzanova and Valentina Gallo and Paolo Arese and Bruno Pradines and Sophie H Adjalley and Denyse Bagrel and Stephanie A Blandin and Michael Lanzer and Elisabeth Davioud-Charvet},
url = {http://aac.asm.org/content/60/9/5146},
doi = {10.1128/AAC.02975-15},
issn = {1098-6596},
year = {2016},
date = {2016-09-01},
journal = {Antimicrob. Agents Chemother.},
volume = {60},
number = {9},
pages = {5146-5158},
abstract = {Previously, we presented the chemical design of a promising series of antimalarial agents, 3-[substituted-benzyl]-menadiones, with potent in vitro and in vivo activities. Ongoing studies on the mode of action of antimalarial 3-[substituted-benzyl]-menadiones revealed that these agents disturb the redox balance of the parasitized erythrocyte by acting as redox-cyclers - a strategy that is broadly recognized for the development of new antimalarial agents. Here, we report a detailed parasitological characterization of the in vitro activity profile of the lead compound 3-[4-(trifluoromethyl)benzyl]-menadione 1c (henceforth called plasmodione) against intra-erythrocytic stages of the human malaria parasite Plasmodium falciparum We show that plasmodione acts rapidly against asexual blood stages, thereby disrupting the clinically relevant intra-erythrocytic life cycle of the parasite, and furthermore has potent activity against early gametocytes. The lead's antiplasmodial activity was unaffected by the most common resistance mechanisms to clinically used antimalarials. Moreover, plasmodione has a low potential to induce drug resistance and a fast killing speed as observed by culturing parasites under continuous drug pressure. Drug interactions with licensed antimalarial drugs were also established using the fixed-ratio isobologram method. Initial toxicological profiling suggests that it is a safe agent for possible human use. Our studies identify plasmodione as a promising antimalarial lead compound and strongly support the future development of redox-active benzylmenadiones as antimalarial agents.},
keywords = {antimalarial, blandin, M3i, parasites, Plasmodium, redox-cycler},
pubstate = {published},
tppubtype = {article}
}
Previously, we presented the chemical design of a promising series of antimalarial agents, 3-[substituted-benzyl]-menadiones, with potent in vitro and in vivo activities. Ongoing studies on the mode of action of antimalarial 3-[substituted-benzyl]-menadiones revealed that these agents disturb the redox balance of the parasitized erythrocyte by acting as redox-cyclers - a strategy that is broadly recognized for the development of new antimalarial agents. Here, we report a detailed parasitological characterization of the in vitro activity profile of the lead compound 3-[4-(trifluoromethyl)benzyl]-menadione 1c (henceforth called plasmodione) against intra-erythrocytic stages of the human malaria parasite Plasmodium falciparum We show that plasmodione acts rapidly against asexual blood stages, thereby disrupting the clinically relevant intra-erythrocytic life cycle of the parasite, and furthermore has potent activity against early gametocytes. The lead's antiplasmodial activity was unaffected by the most common resistance mechanisms to clinically used antimalarials. Moreover, plasmodione has a low potential to induce drug resistance and a fast killing speed as observed by culturing parasites under continuous drug pressure. Drug interactions with licensed antimalarial drugs were also established using the fixed-ratio isobologram method. Initial toxicological profiling suggests that it is a safe agent for possible human use. Our studies identify plasmodione as a promising antimalarial lead compound and strongly support the future development of redox-active benzylmenadiones as antimalarial agents.
2015
Volohonsky Gloria, Terenzi Olivier, Soichot Julien, Naujoks Daniel A, Nolan Tony, Windbichler Nikolai, Kapps Delphine, Smidler Andie L, Vittu Anaïs, Costa Giulia, Steinert Stefanie, Levashina Elena A, Blandin Stéphanie A, Marois Eric
Tools for Anopheles gambiae Transgenesis Article de journal
Dans: G3 (Bethesda), vol. 5, no. 6, p. 1151-63, 2015.
Résumé | Liens | BibTeX | Étiquettes: Anopheles gambiae, bioinformatic, blandin, M3i, marois, transgenesis
@article{G2015,
title = {Tools for Anopheles gambiae Transgenesis},
author = {Gloria Volohonsky and Olivier Terenzi and Julien Soichot and Daniel A Naujoks and Tony Nolan and Nikolai Windbichler and Delphine Kapps and Andie L Smidler and Anaïs Vittu and Giulia Costa and Stefanie Steinert and Elena A Levashina and Stéphanie A Blandin and Eric Marois},
url = {http://www.ncbi.nlm.nih.gov/pubmed/25869647},
year = {2015},
date = {2015-04-13},
journal = {G3 (Bethesda)},
volume = {5},
number = {6},
pages = {1151-63},
abstract = {Transgenesis is an essential tool to investigate gene function and to introduce desired characters in laboratory organisms. Setting-up transgenesis in non-model organisms is challenging due to the diversity of biological life traits and due to knowledge gaps in genomic information. Some procedures will be broadly applicable to many organisms, and others have to be specifically developed for the target species. Transgenesis in disease vector mosquitoes has existed since the 2000s but has remained limited by the delicate biology of these insects. Here, we report a compilation of the transgenesis tools that we have designed for the malaria vector Anopheles gambiae, including new docking strains, convenient transgenesis plasmids, a puromycin resistance selection marker, mosquitoes expressing cre recombinase, and various reporter lines defining the activity of cloned promoters. This toolbox contributed to rendering transgenesis routine in this species and is now enabling the development of increasingly refined genetic manipulations such as targeted mutagenesis. Some of the reagents and procedures reported here are easily transferable to other nonmodel species, including other disease vector or agricultural pest insects.},
keywords = {Anopheles gambiae, bioinformatic, blandin, M3i, marois, transgenesis},
pubstate = {published},
tppubtype = {article}
}
Transgenesis is an essential tool to investigate gene function and to introduce desired characters in laboratory organisms. Setting-up transgenesis in non-model organisms is challenging due to the diversity of biological life traits and due to knowledge gaps in genomic information. Some procedures will be broadly applicable to many organisms, and others have to be specifically developed for the target species. Transgenesis in disease vector mosquitoes has existed since the 2000s but has remained limited by the delicate biology of these insects. Here, we report a compilation of the transgenesis tools that we have designed for the malaria vector Anopheles gambiae, including new docking strains, convenient transgenesis plasmids, a puromycin resistance selection marker, mosquitoes expressing cre recombinase, and various reporter lines defining the activity of cloned promoters. This toolbox contributed to rendering transgenesis routine in this species and is now enabling the development of increasingly refined genetic manipulations such as targeted mutagenesis. Some of the reagents and procedures reported here are easily transferable to other nonmodel species, including other disease vector or agricultural pest insects.
Neafsey D E, Waterhouse R M, Abai M R, Aganezov S S, Alekseyev M A, Allen J E, Amon J, Arcà B, Arensburger P, Artemov G, Assour L A, Basseri H, Berlin A, Birren B W, Blandin Stéphanie A, Brockman A I, Burkot T R, Burt A, Chan C S, Chauve C, Chiu J C, Christensen M, Costantini C, Davidson V L M, Deligianni E, Dottorini T, Dritsou V, Gabriel S B, Guelbeogo W M, Hall A B, Han M W, Hlaing T, Hughes D S T, Jenkins A M, Jiang X, Jungreis I, Kakani E G, Kamali M, Kemppainen P, Kennedy R C, Kirmitzoglou I K, Koekemoer L L, Laban N, Langridge N, Lawniczak M K N, Lirakis M, Lobo N F, Lowy E, MacCallum R M, Mao C, Maslen G, Mbogo C, McCarthy J, Michel K, Mitchell S N, Moore W, Murphy K A, Naumenko A N, Nolan Tony, Novoa E M, O’Loughlin S, Oringanje C, Oshaghi M A, Pakpour N, Papathanos P A, Peery A N, Povelones Michael, Prakash A, Price D A, Rajaraman A, Reimer L J, Rinker D C, Rokas A, Russell T L, Sagnon N F, Sharakhova M V, Shea T, Simão F A, Simard F, Slotman M A, Somboon P, Stegniy V, Struchiner C J, Thomas G W C, Tojo M, Topalis P, Tubio J M C, Unger M F, Vontas J, Walton C, Wilding C S, Willis J H, Wu Y-C, Yan G, Zdobnov E M, Zhou X, Catteruccia Flaminia, Christophides Georges K, Collins F H, Cornman R S, Crisanti Andrea, Donnelly M J, Emrich S J, Fontaine M C, Gelbart W, Hahn M W, Hansen I A, Howell P I, Kafatos Fotis C, Kellis M, Lawson D, Louis C, Luckhart S, Muskavitch M A T, Ribeiro J M, Riehle M A, Sharakhov I V, Tu Z, Zwiebel L J, Besansky N J
Highly evolvable malaria vectors: The genomes of 16 Anopheles mosquitoes. Article de journal
Dans: Science, vol. 347, no. 6217, p. 1258522, 2015.
Résumé | Liens | BibTeX | Étiquettes: Anopheles, blandin, genomes, M3i
@article{DE2015,
title = {Highly evolvable malaria vectors: The genomes of 16 Anopheles mosquitoes.},
author = {D E Neafsey and R M Waterhouse and M R Abai and S S Aganezov and M A Alekseyev and J E Allen and J Amon and B Arcà and P Arensburger and G Artemov and L A Assour and H Basseri and A Berlin and B W Birren and Stéphanie A Blandin and A I Brockman and T R Burkot and A Burt and C S Chan and C Chauve and J C Chiu and M Christensen and C Costantini and V L M Davidson and E Deligianni and T Dottorini and V Dritsou and S B Gabriel and W M Guelbeogo and A B Hall and M W Han and T Hlaing and D S T Hughes and A M Jenkins and X Jiang and I Jungreis and E G Kakani and M Kamali and P Kemppainen and R C Kennedy and I K Kirmitzoglou and L L Koekemoer and N Laban and N Langridge and M K N Lawniczak and M Lirakis and N F Lobo and E Lowy and R M MacCallum and C Mao and G Maslen and C Mbogo and J McCarthy and K Michel and S N Mitchell and W Moore and K A Murphy and A N Naumenko and Tony Nolan and E M Novoa and S O’Loughlin and C Oringanje and M A Oshaghi and N Pakpour and P A Papathanos and A N Peery and Michael Povelones and A Prakash and D A Price and A Rajaraman and L J Reimer and D C Rinker and A Rokas and T L Russell and N F Sagnon and M V Sharakhova and T Shea and F A Simão and F Simard and M A Slotman and P Somboon and V Stegniy and C J Struchiner and G W C Thomas and M Tojo and P Topalis and J M C Tubio and M F Unger and J Vontas and C Walton and C S Wilding and J H Willis and Y-C Wu and G Yan and E M Zdobnov and X Zhou and Flaminia Catteruccia and Georges K Christophides and F H Collins and R S Cornman and Andrea Crisanti and M J Donnelly and S J Emrich and M C Fontaine and W Gelbart and M W Hahn and I A Hansen and P I Howell and Fotis C Kafatos and M Kellis and D Lawson and C Louis and S Luckhart and M A T Muskavitch and J M Ribeiro and M A Riehle and I V Sharakhov and Z Tu and L J Zwiebel and N J Besansky},
url = {http://www.ncbi.nlm.nih.gov/pubmed/25554792},
year = {2015},
date = {2015-01-02},
journal = {Science},
volume = {347},
number = {6217},
pages = {1258522},
abstract = {Variation in vectorial capacity for human malaria among Anopheles mosquito species is determined by many factors, including behavior, immunity, and life history. To investigate the genomic basis of vectorial capacity and explore new avenues for vector control, we sequenced the genomes of 16 anopheline mosquito species from diverse locations spanning ~100 million years of evolution. Comparative analyses show faster rates of gene gain and loss, elevated gene shuffling on the X chromosome, and more intron losses, relative to Drosophila. Some determinants of vectorial capacity, such as chemosensory genes, do not show elevated turnover but instead diversify through protein-sequence changes. This dynamism of anopheline genes and genomes may contribute to their flexible capacity to take advantage of new ecological niches, including adapting to humans as primary hosts.},
keywords = {Anopheles, blandin, genomes, M3i},
pubstate = {published},
tppubtype = {article}
}
Variation in vectorial capacity for human malaria among Anopheles mosquito species is determined by many factors, including behavior, immunity, and life history. To investigate the genomic basis of vectorial capacity and explore new avenues for vector control, we sequenced the genomes of 16 anopheline mosquito species from diverse locations spanning ~100 million years of evolution. Comparative analyses show faster rates of gene gain and loss, elevated gene shuffling on the X chromosome, and more intron losses, relative to Drosophila. Some determinants of vectorial capacity, such as chemosensory genes, do not show elevated turnover but instead diversify through protein-sequence changes. This dynamism of anopheline genes and genomes may contribute to their flexible capacity to take advantage of new ecological niches, including adapting to humans as primary hosts.
2013
Lamacchia Marina, Clayton John Randy, Wang-Sattler R, Steinmetz Lars M, Levashina Elena A, Blandin Stéphanie A
Silencing of Genes and Alleles by RNAi in Anopheles gambiae Article de journal
Dans: Methods Mol Biol., vol. 923, p. 161-76, 2013.
Résumé | BibTeX | Étiquettes: blandin, dsRNA, M3i, RNAi
@article{M2013,
title = {Silencing of Genes and Alleles by RNAi in Anopheles gambiae},
author = {Marina Lamacchia and John Randy Clayton and R Wang-Sattler and Lars M Steinmetz and Elena A Levashina and Stéphanie A Blandin},
year = {2013},
date = {2013-06-13},
journal = {Methods Mol Biol.},
volume = {923},
pages = {161-76},
abstract = {Anopheles gambiae mosquitoes are the major vectors of human malaria parasites. However, mosquitoes are not passive hosts for parasites, actively limiting their development in vivo. Our current understanding of the mosquito antiparasitic response is mostly based on the phenotypic analysis of gene knockdowns obtained by RNA interference (RNAi), through the injection or transfection of long dsRNAs in adult mosquitoes or cultured cells, respectively. Recently, RNAi has been extended to silence specifically one allele of a given gene in a heterozygous context, thus allowing to compare the contribution of different alleles to a phenotype in the same genetic background.},
keywords = {blandin, dsRNA, M3i, RNAi},
pubstate = {published},
tppubtype = {article}
}
Anopheles gambiae mosquitoes are the major vectors of human malaria parasites. However, mosquitoes are not passive hosts for parasites, actively limiting their development in vivo. Our current understanding of the mosquito antiparasitic response is mostly based on the phenotypic analysis of gene knockdowns obtained by RNA interference (RNAi), through the injection or transfection of long dsRNAs in adult mosquitoes or cultured cells, respectively. Recently, RNAi has been extended to silence specifically one allele of a given gene in a heterozygous context, thus allowing to compare the contribution of different alleles to a phenotype in the same genetic background.
2009
Blandin Stéphanie A, Wang-Sattler R, Lamacchia Marina, Gagneur Julien, Lycett G, Ning Y, Levashina Elena A, Steinmetz Lars M
Dissecting the genetic basis of resistance to malaria parasites in Anopheles gambiae Article de journal
Dans: Science, vol. 326, no. 5949, p. 147-50, 2009.
Résumé | Liens | BibTeX | Étiquettes: blandin, M3i, TEP1
@article{SA2009,
title = {Dissecting the genetic basis of resistance to malaria parasites in Anopheles gambiae},
author = {Stéphanie A Blandin and R Wang-Sattler and Marina Lamacchia and Julien Gagneur and G Lycett and Y Ning and Elena A Levashina and Lars M Steinmetz},
url = {http://www.ncbi.nlm.nih.gov/pubmed/19797663},
year = {2009},
date = {2009-10-02},
journal = {Science},
volume = {326},
number = {5949},
pages = {147-50},
abstract = {The ability of Anopheles gambiae mosquitoes to transmit Plasmodium parasites is highly variable between individuals. However, the genetic basis of this variability has remained unknown. We combined genome-wide mapping and reciprocal allele-specific RNA interference (rasRNAi) to identify the genomic locus that confers resistance to malaria parasites and demonstrated that polymorphisms in a single gene encoding the antiparasitic thioester-containing protein 1 (TEP1) explain a substantial part of the variability in parasite killing. The link between TEP1 alleles and resistance to malaria may offer new tools for controlling malaria transmission. The successful application of rasRNAi in Anopheles suggests that it could also be applied to other organisms where RNAi is feasible to dissect complex phenotypes to the level of individual quantitative trait alleles.},
keywords = {blandin, M3i, TEP1},
pubstate = {published},
tppubtype = {article}
}
The ability of Anopheles gambiae mosquitoes to transmit Plasmodium parasites is highly variable between individuals. However, the genetic basis of this variability has remained unknown. We combined genome-wide mapping and reciprocal allele-specific RNA interference (rasRNAi) to identify the genomic locus that confers resistance to malaria parasites and demonstrated that polymorphisms in a single gene encoding the antiparasitic thioester-containing protein 1 (TEP1) explain a substantial part of the variability in parasite killing. The link between TEP1 alleles and resistance to malaria may offer new tools for controlling malaria transmission. The successful application of rasRNAi in Anopheles suggests that it could also be applied to other organisms where RNAi is feasible to dissect complex phenotypes to the level of individual quantitative trait alleles.
Fraiture Malou, Baxter Richard H G, Steinert Stefanie, Chelliah Yogarany, Frolet Cécile, Quispe-Tintaya Wilber, Hoffmann Jules A, Blandin Stéphanie A, Levashina Elena A
Two mosquito LRR proteins function as complement control factors in the TEP1-mediated killing of Plasmodium Article de journal
Dans: Cell Host Microbe, vol. 5, no. 3, p. 273–284, 2009, ISSN: 1934-6069.
Résumé | Liens | BibTeX | Étiquettes: Animals, Anopheles, APL1, Biological, blandin, Complement System Proteins, Hemolymph, hoffmann, Immunologic Factors, LRIM1, M3i, Models, Plasmodium, Protein Binding, Proteins, TEP1
@article{fraiture_two_2009,
title = {Two mosquito LRR proteins function as complement control factors in the TEP1-mediated killing of Plasmodium},
author = {Malou Fraiture and Richard H G Baxter and Stefanie Steinert and Yogarany Chelliah and Cécile Frolet and Wilber Quispe-Tintaya and Jules A Hoffmann and Stéphanie A Blandin and Elena A Levashina},
doi = {10.1016/j.chom.2009.01.005},
issn = {1934-6069},
year = {2009},
date = {2009-03-01},
journal = {Cell Host Microbe},
volume = {5},
number = {3},
pages = {273--284},
abstract = {Plasmodium development within Anopheles mosquitoes is a vulnerable step in the parasite transmission cycle, and targeting this step represents a promising strategy for malaria control. The thioester-containing complement-like protein TEP1 and two leucine-rich repeat (LRR) proteins, LRIM1 and APL1, have been identified as major mosquito factors that regulate parasite loads. Here, we show that LRIM1 and APL1 are required for binding of TEP1 to parasites. RNAi silencing of the LRR-encoding genes results in deposition of TEP1 on Anopheles tissues, thereby depleting TEP1 from circulation in the hemolymph and impeding its binding to Plasmodium. LRIM1 and APL1 not only stabilize circulating TEP1, they also stabilize each other prior to their interaction with TEP1. Our results indicate that three major antiparasitic factors in mosquitoes jointly function as a complement-like system in parasite killing, and they reveal a role for LRR proteins as complement control factors.},
keywords = {Animals, Anopheles, APL1, Biological, blandin, Complement System Proteins, Hemolymph, hoffmann, Immunologic Factors, LRIM1, M3i, Models, Plasmodium, Protein Binding, Proteins, TEP1},
pubstate = {published},
tppubtype = {article}
}
Plasmodium development within Anopheles mosquitoes is a vulnerable step in the parasite transmission cycle, and targeting this step represents a promising strategy for malaria control. The thioester-containing complement-like protein TEP1 and two leucine-rich repeat (LRR) proteins, LRIM1 and APL1, have been identified as major mosquito factors that regulate parasite loads. Here, we show that LRIM1 and APL1 are required for binding of TEP1 to parasites. RNAi silencing of the LRR-encoding genes results in deposition of TEP1 on Anopheles tissues, thereby depleting TEP1 from circulation in the hemolymph and impeding its binding to Plasmodium. LRIM1 and APL1 not only stabilize circulating TEP1, they also stabilize each other prior to their interaction with TEP1. Our results indicate that three major antiparasitic factors in mosquitoes jointly function as a complement-like system in parasite killing, and they reveal a role for LRR proteins as complement control factors.
2008
Blandin Stéphanie A, Marois Eric, Levashina Elena A
Antimalarial responses in Anopheles gambiae: from a complement-like protein to a complement-like pathway Article de journal
Dans: Cell Host Microbe., vol. 3, no. 6, p. 364-74, 2008.
Résumé | Liens | BibTeX | Étiquettes: blandin, M3i, marois, TEP1
@article{SA2008,
title = {Antimalarial responses in Anopheles gambiae: from a complement-like protein to a complement-like pathway},
author = {Stéphanie A Blandin and Eric Marois and Elena A Levashina},
url = {http://www.ncbi.nlm.nih.gov/pubmed/18541213},
year = {2008},
date = {2008-06-12},
journal = {Cell Host Microbe.},
volume = {3},
number = {6},
pages = {364-74},
abstract = {Malaria transmission between humans depends on the ability of Anopheles mosquitoes to support Plasmodium development. New perspectives in vector control are emerging from understanding the mosquito immune system, which plays critical roles in parasite recognition and killing. A number of factors controlling this process have been recently identified, and key among them is TEP1, a homolog of human complement factor C3 whose binding to the parasite surface targets it for subsequent killing. Here, we review our current knowledge of mosquito factors that respond to Plasmodium infection and elaborate on the activity and mode of action of the TEP1 complement-like pathway.},
keywords = {blandin, M3i, marois, TEP1},
pubstate = {published},
tppubtype = {article}
}
Malaria transmission between humans depends on the ability of Anopheles mosquitoes to support Plasmodium development. New perspectives in vector control are emerging from understanding the mosquito immune system, which plays critical roles in parasite recognition and killing. A number of factors controlling this process have been recently identified, and key among them is TEP1, a homolog of human complement factor C3 whose binding to the parasite surface targets it for subsequent killing. Here, we review our current knowledge of mosquito factors that respond to Plasmodium infection and elaborate on the activity and mode of action of the TEP1 complement-like pathway.
Blandin Stéphanie A, Levashina Elena A
Reverse Genetics Analysis of Antiparasitic Responses in the Malaria Vector, Anopheles gambiae Article de journal
Dans: Methods Mol Biol., vol. 415, p. 365-77, 2008.
Résumé | Liens | BibTeX | Étiquettes: blandin, M3i, RNAi
@article{SA2008b,
title = {Reverse Genetics Analysis of Antiparasitic Responses in the Malaria Vector, Anopheles gambiae},
author = {Stéphanie A Blandin and Elena A Levashina},
url = {http://www.ncbi.nlm.nih.gov/pubmed/18370165},
year = {2008},
date = {2008-01-01},
journal = {Methods Mol Biol.},
volume = {415},
pages = {365-77},
abstract = {Anopheles mosquitoes are the major vectors of human malaria parasites. Mosquito-parasite interactions are critical for disease transmission and therefore represent a potential target for malaria control strategies. Mosquitoes mount potent antiparasitic responses, and identification of mosquito factors that limit parasite development is one of the major objectives in the field. To address this question, we have developed a convenient reverse genetics approach by injection of double-stranded RNA (dsRNA) in adult mosquitoes, to evaluate the function of candidate genes in mosquito antiparasitic responses.},
keywords = {blandin, M3i, RNAi},
pubstate = {published},
tppubtype = {article}
}
Anopheles mosquitoes are the major vectors of human malaria parasites. Mosquito-parasite interactions are critical for disease transmission and therefore represent a potential target for malaria control strategies. Mosquitoes mount potent antiparasitic responses, and identification of mosquito factors that limit parasite development is one of the major objectives in the field. To address this question, we have developed a convenient reverse genetics approach by injection of double-stranded RNA (dsRNA) in adult mosquitoes, to evaluate the function of candidate genes in mosquito antiparasitic responses.
2007
Blandin Stéphanie A, Levashina Elena A
Phagocytosis in mosquito immune responses Article de journal
Dans: Immunol Rev., vol. 219, p. 8-16, 2007.
Résumé | Liens | BibTeX | Étiquettes: blandin, M3i, Phagocytosis, RNAi
@article{SA2007,
title = {Phagocytosis in mosquito immune responses},
author = {Stéphanie A Blandin and Elena A Levashina},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17850478},
year = {2007},
date = {2007-10-01},
journal = {Immunol Rev.},
volume = {219},
pages = {8-16},
abstract = {Anopheles mosquitoes are the only vectors of human malaria parasites. Mosquito-parasite interactions are critical for disease transmission and therefore are a potential target for malaria control strategies. Mosquitoes mount potent immune responses that efficiently limit proliferation of a variety of infectious agents, including microbial pathogens and malaria parasites. The recent completion of the Anopheles gambiae genome sequencing project combined with the development of the powerful RNA interference-based gene silencing helped to identify major players of the immune defenses and uncovered evolutionarily conserved mechanisms in the anti-bacterial and anti-Plasmodium responses. The anti-bacterial responses are based on phagocytosis at early steps of infections, followed, several hours later, by the synthesis of anti-microbial peptides. The principal regulators of anti-parasitic responses are predominantly synthesized by the mosquito blood cells; however, the exact molecular mechanisms of parasite killing remain unclear. Several regulators of phagocytosis are also required for efficient parasite killing. Here, we summarize our current knowledge of the anti-bacterial and anti-parasitic responses, with the particular emphasis on the role of phagocytosis in mosquito immunity.},
keywords = {blandin, M3i, Phagocytosis, RNAi},
pubstate = {published},
tppubtype = {article}
}
Anopheles mosquitoes are the only vectors of human malaria parasites. Mosquito-parasite interactions are critical for disease transmission and therefore are a potential target for malaria control strategies. Mosquitoes mount potent immune responses that efficiently limit proliferation of a variety of infectious agents, including microbial pathogens and malaria parasites. The recent completion of the Anopheles gambiae genome sequencing project combined with the development of the powerful RNA interference-based gene silencing helped to identify major players of the immune defenses and uncovered evolutionarily conserved mechanisms in the anti-bacterial and anti-Plasmodium responses. The anti-bacterial responses are based on phagocytosis at early steps of infections, followed, several hours later, by the synthesis of anti-microbial peptides. The principal regulators of anti-parasitic responses are predominantly synthesized by the mosquito blood cells; however, the exact molecular mechanisms of parasite killing remain unclear. Several regulators of phagocytosis are also required for efficient parasite killing. Here, we summarize our current knowledge of the anti-bacterial and anti-parasitic responses, with the particular emphasis on the role of phagocytosis in mosquito immunity.
Baxter Richard H, Chang C I, Chelliah Y, Blandin Stéphanie A, Levashina Elena A, Deisenhofer J
Structural basis for conserved complement factor-like function in the antimalarial protein TEP1 Article de journal
Dans: Proc Natl Acad Sci U S A., vol. 104, no. 28, p. 11615-20, 2007.
Résumé | Liens | BibTeX | Étiquettes: blandin, M3i, TEP1
@article{RH2007,
title = {Structural basis for conserved complement factor-like function in the antimalarial protein TEP1},
author = {Richard H Baxter and C I Chang and Y Chelliah and Stéphanie A Blandin and Elena A Levashina and J Deisenhofer},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17606907},
year = {2007},
date = {2007-07-10},
journal = {Proc Natl Acad Sci U S A.},
volume = {104},
number = {28},
pages = {11615-20},
abstract = {Thioester-containing proteins (TEPs) are a major component of the innate immune response of insects to invasion by bacteria and protozoa. TEPs form a distinct clade of a superfamily that includes the pan-protease inhibitors alpha(2)-macroglobulins and vertebrate complement factors. The essential feature of these proteins is a sequestered thioester bond that, after cleavage in a protease-sensitive region of the protein, is activated and covalently binds to its target. Recently, TEP1 from the malarial vector Anopheles gambiae was shown to mediate recognition and killing of ookinetes from the malarial parasite Plasmodium berghei, a model for the human malarial parasite Plasmodium falciparum. Here, we present the crystal structure of the TEP1 isoform TEP1r. Although the overall protein fold of TEP1r resembles that of complement factor C3, the TEP1r domains are repositioned to stabilize the inactive conformation of the molecule (containing an intact thioester) in the absence of the anaphylotoxin domain, a central component of complement factors. The structure of TEP1r provides a molecular basis for the differences between TEP1 alleles TEP1r and TEP1s, which correlate with resistance of A. gambiae to infection by P. berghei.},
keywords = {blandin, M3i, TEP1},
pubstate = {published},
tppubtype = {article}
}
Thioester-containing proteins (TEPs) are a major component of the innate immune response of insects to invasion by bacteria and protozoa. TEPs form a distinct clade of a superfamily that includes the pan-protease inhibitors alpha(2)-macroglobulins and vertebrate complement factors. The essential feature of these proteins is a sequestered thioester bond that, after cleavage in a protease-sensitive region of the protein, is activated and covalently binds to its target. Recently, TEP1 from the malarial vector Anopheles gambiae was shown to mediate recognition and killing of ookinetes from the malarial parasite Plasmodium berghei, a model for the human malarial parasite Plasmodium falciparum. Here, we present the crystal structure of the TEP1 isoform TEP1r. Although the overall protein fold of TEP1r resembles that of complement factor C3, the TEP1r domains are repositioned to stabilize the inactive conformation of the molecule (containing an intact thioester) in the absence of the anaphylotoxin domain, a central component of complement factors. The structure of TEP1r provides a molecular basis for the differences between TEP1 alleles TEP1r and TEP1s, which correlate with resistance of A. gambiae to infection by P. berghei.
Waterhouse R M, Kriventseva E V, Meister Stephan, Xi Z, Alvarez K S, Bartholomay L C, Barillas-Mury Carolina, Bian G, Blandin Stéphanie A, Christensen B M, Dong Y, Jiang H, Kanost M R, Koutsos A C, Levashina Elena A, Li J, Ligoxygakis Petros, Maccallum R M, Mayhew G F, Mendes A, Michel K, Osta M A, Paskewitz S, Shin S W, Vlachou D, Wang L, Wei W, Zheng L, Zou Z, Severson D W, Raikhel A S, Kafatos Fotis C, Dimopoulos G, Zdobnov E M, Christophides G K
Evolutionary dynamics of immune-related genes and pathways in disease-vector mosquitoes Article de journal
Dans: Science, vol. 316, p. 5832, 2007.
Résumé | Liens | BibTeX | Étiquettes: blandin, Evolution, M3i, Phylogeny
@article{RM2007,
title = {Evolutionary dynamics of immune-related genes and pathways in disease-vector mosquitoes},
author = {R M Waterhouse and E V Kriventseva and Stephan Meister and Z Xi and K S Alvarez and L C Bartholomay and Carolina Barillas-Mury and G Bian and Stéphanie A Blandin and B M Christensen and Y Dong and H Jiang and M R Kanost and A C Koutsos and Elena A Levashina and J Li and Petros Ligoxygakis and R M Maccallum and G F Mayhew and A Mendes and K Michel and M A Osta and S Paskewitz and S W Shin and D Vlachou and L Wang and W Wei and L Zheng and Z Zou and D W Severson and A S Raikhel and Fotis C Kafatos and G Dimopoulos and E M Zdobnov and G K Christophides},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17588928},
year = {2007},
date = {2007-06-22},
journal = {Science},
volume = {316},
pages = {5832},
abstract = {Mosquitoes are vectors of parasitic and viral diseases of immense importance for public health. The acquisition of the genome sequence of the yellow fever and Dengue vector, Aedes aegypti (Aa), has enabled a comparative phylogenomic analysis of the insect immune repertoire: in Aa, the malaria vector Anopheles gambiae (Ag), and the fruit fly Drosophila melanogaster (Dm). Analysis of immune signaling pathways and response modules reveals both conservative and rapidly evolving features associated with different functional gene categories and particular aspects of immune reactions. These dynamics reflect in part continuous readjustment between accommodation and rejection of pathogens and suggest how innate immunity may have evolved.},
keywords = {blandin, Evolution, M3i, Phylogeny},
pubstate = {published},
tppubtype = {article}
}
Mosquitoes are vectors of parasitic and viral diseases of immense importance for public health. The acquisition of the genome sequence of the yellow fever and Dengue vector, Aedes aegypti (Aa), has enabled a comparative phylogenomic analysis of the insect immune repertoire: in Aa, the malaria vector Anopheles gambiae (Ag), and the fruit fly Drosophila melanogaster (Dm). Analysis of immune signaling pathways and response modules reveals both conservative and rapidly evolving features associated with different functional gene categories and particular aspects of immune reactions. These dynamics reflect in part continuous readjustment between accommodation and rejection of pathogens and suggest how innate immunity may have evolved.
Lefevre T, Thomas F, Schwartz A, Levashina Elena A, Blandin Stéphanie A, Brizard J-P, Bourligu Le L, Demettre E, Renaud F, Biron D G
Malaria Plasmodium agent induces alteration in the head proteome of their Anopheles mosquito host Article de journal
Dans: Proteomics, vol. 7, no. 11, p. 1908-15, 2007.
Résumé | Liens | BibTeX | Étiquettes: blandin, M3i, Proteome
@article{T2007,
title = {Malaria Plasmodium agent induces alteration in the head proteome of their Anopheles mosquito host},
author = {T Lefevre and F Thomas and A Schwartz and Elena A Levashina and Stéphanie A Blandin and J-P Brizard and Le L Bourligu and E Demettre and F Renaud and D G Biron},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17464940},
year = {2007},
date = {2007-06-01},
journal = {Proteomics},
volume = {7},
number = {11},
pages = {1908-15},
abstract = {Despite increasing evidence of behavioural manipulation of their vectors by pathogens, the underlying mechanisms causing infected vectors to act in ways that benefit pathogen transmission remain enigmatic in most cases. Here, 2-D DIGE coupled with MS were employed to analyse and compare the head proteome of mosquitoes (Anopheles gambiae sensu stricto (Giles)) infected with the malarial parasite (Plasmodium berghei) with that of uninfected mosquitoes. This approach detected altered levels of 12 protein spots in the head of mosquitoes infected with sporozoites. These proteins were subsequently identified using MS and functionally classified as belonging to metabolic, synaptic, molecular chaperone, signalling, and cytoskeletal groups. Our results indicate an altered energy metabolism in the head of sporozoite-infected mosquitoes. Some of the up-/down-regulated proteins identified, such as synapse-associated protein, 14-3-3 protein and calmodulin, have previously been shown to play critical roles in the CNS of both invertebrates and vertebrates. Furthermore, a heat shock response (HSP 20) and a variation of cytoarchitecture (tropomyosins) have been shown. Discovery of these proteins sheds light on potential molecular mechanisms that underlie behavioural modifications and offers new insights into the study of intimate interactions between Plasmodium and its Anopheles vector.},
keywords = {blandin, M3i, Proteome},
pubstate = {published},
tppubtype = {article}
}
Despite increasing evidence of behavioural manipulation of their vectors by pathogens, the underlying mechanisms causing infected vectors to act in ways that benefit pathogen transmission remain enigmatic in most cases. Here, 2-D DIGE coupled with MS were employed to analyse and compare the head proteome of mosquitoes (Anopheles gambiae sensu stricto (Giles)) infected with the malarial parasite (Plasmodium berghei) with that of uninfected mosquitoes. This approach detected altered levels of 12 protein spots in the head of mosquitoes infected with sporozoites. These proteins were subsequently identified using MS and functionally classified as belonging to metabolic, synaptic, molecular chaperone, signalling, and cytoskeletal groups. Our results indicate an altered energy metabolism in the head of sporozoite-infected mosquitoes. Some of the up-/down-regulated proteins identified, such as synapse-associated protein, 14-3-3 protein and calmodulin, have previously been shown to play critical roles in the CNS of both invertebrates and vertebrates. Furthermore, a heat shock response (HSP 20) and a variation of cytoarchitecture (tropomyosins) have been shown. Discovery of these proteins sheds light on potential molecular mechanisms that underlie behavioural modifications and offers new insights into the study of intimate interactions between Plasmodium and its Anopheles vector.
Wang-Sattler Rui, Blandin Stephanie A, Ning Ye, Blass Claudia, Dolo Guimogo, Touré Yeya T, delle Torre Alessandra, Lanzaro Gregory C, Steinmetz Lars M, Kafatos Fotis C, Zheng Liangbiao
Mosaic genome architecture of the Anopheles gambiae species complex Article de journal
Dans: PLoS ONE, vol. 2, no. 11, p. e1249, 2007, ISSN: 1932-6203.
Résumé | Liens | BibTeX | Étiquettes: Animals, Anopheles gambiae, Artificial, Bacterial, Biological Evolution, blandin, Chromosomes, Female, Genetic Markers, Genetic Variation, Genome, M3i, Microsatellite Repeats, Mosaicism
@article{wang-sattler_mosaic_2007,
title = {Mosaic genome architecture of the Anopheles gambiae species complex},
author = {Rui Wang-Sattler and Stephanie A Blandin and Ye Ning and Claudia Blass and Guimogo Dolo and Yeya T Touré and Alessandra delle Torre and Gregory C Lanzaro and Lars M Steinmetz and Fotis C Kafatos and Liangbiao Zheng},
doi = {10.1371/journal.pone.0001249},
issn = {1932-6203},
year = {2007},
date = {2007-01-01},
journal = {PLoS ONE},
volume = {2},
number = {11},
pages = {e1249},
abstract = {BACKGROUND: Attempts over the last three decades to reconstruct the phylogenetic history of the Anopheles gambiae species complex have been important for developing better strategies to control malaria transmission. METHODOLOGY: We used fingerprint genotyping data from 414 field-collected female mosquitoes at 42 microsatellite loci to infer the evolutionary relationships of four species in the A. gambiae complex, the two major malaria vectors A. gambiae sensu stricto (A. gambiae s.s.) and A. arabiensis, as well as two minor vectors, A. merus and A. melas. PRINCIPAL FINDINGS: We identify six taxonomic units, including a clear separation of West and East Africa A. gambiae s.s. S molecular forms. We show that the phylogenetic relationships vary widely between different genomic regions, thus demonstrating the mosaic nature of the genome of these species. The two major malaria vectors are closely related and closer to A. merus than to A. melas at the genome-wide level, which is also true if only autosomes are considered. However, within the Xag inversion region of the X chromosome, the M and two S molecular forms are most similar to A. merus. Near the X centromere, outside the Xag region, the two S forms are highly dissimilar to the other taxa. Furthermore, our data suggest that the centromeric region of chromosome 3 is a strong discriminator between the major and minor malaria vectors. CONCLUSIONS: Although further studies are needed to elucidate the basis of the phylogenetic variation among the different regions of the genome, the preponderance of sympatric admixtures among taxa strongly favor introgression of different genomic regions between species, rather than lineage sorting of ancestral polymorphism, as a possible mechanism.},
keywords = {Animals, Anopheles gambiae, Artificial, Bacterial, Biological Evolution, blandin, Chromosomes, Female, Genetic Markers, Genetic Variation, Genome, M3i, Microsatellite Repeats, Mosaicism},
pubstate = {published},
tppubtype = {article}
}
BACKGROUND: Attempts over the last three decades to reconstruct the phylogenetic history of the Anopheles gambiae species complex have been important for developing better strategies to control malaria transmission. METHODOLOGY: We used fingerprint genotyping data from 414 field-collected female mosquitoes at 42 microsatellite loci to infer the evolutionary relationships of four species in the A. gambiae complex, the two major malaria vectors A. gambiae sensu stricto (A. gambiae s.s.) and A. arabiensis, as well as two minor vectors, A. merus and A. melas. PRINCIPAL FINDINGS: We identify six taxonomic units, including a clear separation of West and East Africa A. gambiae s.s. S molecular forms. We show that the phylogenetic relationships vary widely between different genomic regions, thus demonstrating the mosaic nature of the genome of these species. The two major malaria vectors are closely related and closer to A. merus than to A. melas at the genome-wide level, which is also true if only autosomes are considered. However, within the Xag inversion region of the X chromosome, the M and two S molecular forms are most similar to A. merus. Near the X centromere, outside the Xag region, the two S forms are highly dissimilar to the other taxa. Furthermore, our data suggest that the centromeric region of chromosome 3 is a strong discriminator between the major and minor malaria vectors. CONCLUSIONS: Although further studies are needed to elucidate the basis of the phylogenetic variation among the different regions of the genome, the preponderance of sympatric admixtures among taxa strongly favor introgression of different genomic regions between species, rather than lineage sorting of ancestral polymorphism, as a possible mechanism.
2006
Frolet Cécile, Thoma Martine, Blandin Stéphanie A, Hoffmann Jules A, Levashina Elena A
Boosting NF-kappaB-dependent basal immunity of Anopheles gambiae aborts development of Plasmodium berghei Article de journal
Dans: Immunity, vol. 25, no. 4, p. 677–685, 2006, ISSN: 1074-7613.
Résumé | Liens | BibTeX | Étiquettes: Animals, Anopheles gambiae, blandin, Gene Expression, Gene Expression Regulation, Genes, hoffmann, Immunity, Insect, M3i, NF-kappa B, Plasmodium berghei, telomerase
@article{frolet_boosting_2006,
title = {Boosting NF-kappaB-dependent basal immunity of Anopheles gambiae aborts development of Plasmodium berghei},
author = {Cécile Frolet and Martine Thoma and Stéphanie A Blandin and Jules A Hoffmann and Elena A Levashina},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17045818},
doi = {10.1016/j.immuni.2006.08.019},
issn = {1074-7613},
year = {2006},
date = {2006-10-01},
journal = {Immunity},
volume = {25},
number = {4},
pages = {677--685},
abstract = {Anopheles gambiae, the major vector for the protozoan malaria parasite Plasmodium falciparum, mounts powerful antiparasitic responses that cause marked parasite loss during midgut invasion. Here, we showed that these antiparasitic defenses were composed of pre- and postinvasion phases and that the preinvasion phase was predominantly regulated by Rel1 and Rel2 members of the NF-kappaB transcription factors. Concurrent silencing of Rel1 and Rel2 decreased the basal expression of the major antiparasitic genes TEP1 and LRIM1 and abolished resistance of Anopheles to the rodent malaria parasite P. berghei. Conversely, depletion of a negative regulator of Rel1, Cactus, prior to infection, enhanced the basal expression of TEP1 and of other immune factors and completely prevented parasite development. Our findings uncover the crucial role of the preinvasion defense in the elimination of parasites, which is at least in part based on circulating blood molecules.},
keywords = {Animals, Anopheles gambiae, blandin, Gene Expression, Gene Expression Regulation, Genes, hoffmann, Immunity, Insect, M3i, NF-kappa B, Plasmodium berghei, telomerase},
pubstate = {published},
tppubtype = {article}
}
Anopheles gambiae, the major vector for the protozoan malaria parasite Plasmodium falciparum, mounts powerful antiparasitic responses that cause marked parasite loss during midgut invasion. Here, we showed that these antiparasitic defenses were composed of pre- and postinvasion phases and that the preinvasion phase was predominantly regulated by Rel1 and Rel2 members of the NF-kappaB transcription factors. Concurrent silencing of Rel1 and Rel2 decreased the basal expression of the major antiparasitic genes TEP1 and LRIM1 and abolished resistance of Anopheles to the rodent malaria parasite P. berghei. Conversely, depletion of a negative regulator of Rel1, Cactus, prior to infection, enhanced the basal expression of TEP1 and of other immune factors and completely prevented parasite development. Our findings uncover the crucial role of the preinvasion defense in the elimination of parasites, which is at least in part based on circulating blood molecules.
2005
Moita L F, Wang R, Michel K, Blandin Stéphanie A, Zimmermann T, Levashina Elena A, Kafatos Fotis C
In Vivo Identification of Novel Regulators and Conserved Pathways of Phagocytosis in A. gambiae Article de journal
Dans: Immunity., vol. 23, no. 1, p. 65-73, 2005.
Résumé | Liens | BibTeX | Étiquettes: blandin, M3i, RNAi
@article{LF2005,
title = {In Vivo Identification of Novel Regulators and Conserved Pathways of Phagocytosis in A. gambiae},
author = {L F Moita and R Wang and K Michel and Stéphanie A Blandin and T Zimmermann and Elena A Levashina and Fotis C Kafatos},
url = {http://www.ncbi.nlm.nih.gov/pubmed/16039580},
year = {2005},
date = {2005-07-01},
journal = {Immunity.},
volume = {23},
number = {1},
pages = {65-73},
abstract = {Anopheles gambiae uses effective immune responses, including phagocytosis, to fight microbial infection. We have developed a semiquantitative phagocytosis test and used it in conjunction with dsRNA gene silencing to test the in vivo roles of 71 candidate genes in phagocytosis of Escherichia coli and Staphylococcus aureus. Here, we show that inactivation of 26 genes changes the phagocytic activity by more than 45% and that two pathways similar to those that mediate apoptotic cell removal in Caenorhabditis elegans are used in A. gambiae for phagocytosis of microorganisms. Simultaneous inactivation of the identified regulators of phagocytosis and conserved components defining each signaling pathway permitted provisional assignment of the novel regulators to one or the other pathway. Pathway inactivation enhances at least three times the ability of E. coli and S. aureus to proliferate in the mosquito. Interestingly, mosquito survival is not compromised even if both pathways are perturbed simultaneously.},
keywords = {blandin, M3i, RNAi},
pubstate = {published},
tppubtype = {article}
}
Anopheles gambiae uses effective immune responses, including phagocytosis, to fight microbial infection. We have developed a semiquantitative phagocytosis test and used it in conjunction with dsRNA gene silencing to test the in vivo roles of 71 candidate genes in phagocytosis of Escherichia coli and Staphylococcus aureus. Here, we show that inactivation of 26 genes changes the phagocytic activity by more than 45% and that two pathways similar to those that mediate apoptotic cell removal in Caenorhabditis elegans are used in A. gambiae for phagocytosis of microorganisms. Simultaneous inactivation of the identified regulators of phagocytosis and conserved components defining each signaling pathway permitted provisional assignment of the novel regulators to one or the other pathway. Pathway inactivation enhances at least three times the ability of E. coli and S. aureus to proliferate in the mosquito. Interestingly, mosquito survival is not compromised even if both pathways are perturbed simultaneously.
2004
Blandin Stéphanie A, Levashina Elena A
Curing mosquitoes to control malaria ? Article de journal
Dans: Med Sci (Paris)., vol. 20, no. 8-9, p. 740-2, 2004.
Liens | BibTeX | Étiquettes: blandin, M3i, population control
@article{S2004,
title = {Curing mosquitoes to control malaria ?},
author = {Stéphanie A Blandin and Elena A Levashina},
url = {http://www.ncbi.nlm.nih.gov/pubmed/15361335},
year = {2004},
date = {2004-08-02},
journal = {Med Sci (Paris).},
volume = {20},
number = {8-9},
pages = {740-2},
keywords = {blandin, M3i, population control},
pubstate = {published},
tppubtype = {article}
}
Budd A, Blandin Stéphanie A, Levashina Elena A, Gibson T J
Bacterial alpha2-macroglobulins: colonization factors acquired by horizontal gene transfer from the metazoan genome ? Article de journal
Dans: Genome Biol., vol. 5, no. 6, p. R38, 2004.
Résumé | Liens | BibTeX | Étiquettes: alpha2-macroglobulins, blandin, M3i
@article{EA2004b,
title = {Bacterial alpha2-macroglobulins: colonization factors acquired by horizontal gene transfer from the metazoan genome ?},
author = {A Budd and Stéphanie A Blandin and Elena A Levashina and T J Gibson},
url = {http://www.ncbi.nlm.nih.gov/pubmed/15186489},
year = {2004},
date = {2004-05-26},
journal = {Genome Biol.},
volume = {5},
number = {6},
pages = {R38},
abstract = {BACKGROUND: Invasive bacteria are known to have captured and adapted eukaryotic host genes. They also readily acquire colonizing genes from other bacteria by horizontal gene transfer. Closely related species such as Helicobacter pylori and Helicobacter hepaticus, which exploit different host tissues, share almost none of their colonization genes. The protease inhibitor alpha2-macroglobulin provides a major metazoan defense against invasive bacteria, trapping attacking proteases required by parasites for successful invasion. RESULTS: Database searches with metazoan alpha2-macroglobulin sequences revealed homologous sequences in bacterial proteomes. The bacterial alpha2-macroglobulin phylogenetic distribution is patchy and violates the vertical descent model. Bacterial alpha2-macroglobulin genes are found in diverse clades, including purple bacteria (proteobacteria), fusobacteria, spirochetes, bacteroidetes, deinococcids, cyanobacteria, planctomycetes and thermotogae. Most bacterial species with bacterial alpha2-macroglobulin genes exploit higher eukaryotes (multicellular plants and animals) as hosts. Both pathogenically invasive and saprophytically colonizing species possess bacterial alpha2-macroglobulins, indicating that bacterial alpha2-macroglobulin is a colonization rather than a virulence factor. CONCLUSIONS: Metazoan alpha2-macroglobulins inhibit proteases of pathogens. The bacterial homologs may function in reverse to block host antimicrobial defenses. Alpha2-macroglobulin was probably acquired one or more times from metazoan hosts and has then spread widely through other colonizing bacterial species by more than 10 independent horizontal gene transfers. yfhM-like bacterial alpha2-macroglobulin genes are often found tightly linked with pbpC, encoding an atypical peptidoglycan transglycosylase, PBP1C, that does not function in vegetative peptidoglycan synthesis. We suggest that YfhM and PBP1C are coupled together as a periplasmic defense and repair system. Bacterial alpha2-macroglobulins might provide useful targets for enhancing vaccine efficacy in combating infections.},
keywords = {alpha2-macroglobulins, blandin, M3i},
pubstate = {published},
tppubtype = {article}
}
BACKGROUND: Invasive bacteria are known to have captured and adapted eukaryotic host genes. They also readily acquire colonizing genes from other bacteria by horizontal gene transfer. Closely related species such as Helicobacter pylori and Helicobacter hepaticus, which exploit different host tissues, share almost none of their colonization genes. The protease inhibitor alpha2-macroglobulin provides a major metazoan defense against invasive bacteria, trapping attacking proteases required by parasites for successful invasion. RESULTS: Database searches with metazoan alpha2-macroglobulin sequences revealed homologous sequences in bacterial proteomes. The bacterial alpha2-macroglobulin phylogenetic distribution is patchy and violates the vertical descent model. Bacterial alpha2-macroglobulin genes are found in diverse clades, including purple bacteria (proteobacteria), fusobacteria, spirochetes, bacteroidetes, deinococcids, cyanobacteria, planctomycetes and thermotogae. Most bacterial species with bacterial alpha2-macroglobulin genes exploit higher eukaryotes (multicellular plants and animals) as hosts. Both pathogenically invasive and saprophytically colonizing species possess bacterial alpha2-macroglobulins, indicating that bacterial alpha2-macroglobulin is a colonization rather than a virulence factor. CONCLUSIONS: Metazoan alpha2-macroglobulins inhibit proteases of pathogens. The bacterial homologs may function in reverse to block host antimicrobial defenses. Alpha2-macroglobulin was probably acquired one or more times from metazoan hosts and has then spread widely through other colonizing bacterial species by more than 10 independent horizontal gene transfers. yfhM-like bacterial alpha2-macroglobulin genes are often found tightly linked with pbpC, encoding an atypical peptidoglycan transglycosylase, PBP1C, that does not function in vegetative peptidoglycan synthesis. We suggest that YfhM and PBP1C are coupled together as a periplasmic defense and repair system. Bacterial alpha2-macroglobulins might provide useful targets for enhancing vaccine efficacy in combating infections.
Blandin Stéphanie A, Levashina Elena A
Thioester-containing proteins in insect immunity Article de journal
Dans: Mol Immunol., vol. 40, no. 12, p. 903-8, 2004.
Résumé | BibTeX | Étiquettes: blandin, M3i, TEP1
@article{S2004b,
title = {Thioester-containing proteins in insect immunity},
author = {Stéphanie A Blandin and Elena A Levashina},
year = {2004},
date = {2004-02-01},
journal = {Mol Immunol.},
volume = {40},
number = {12},
pages = {903-8},
abstract = {Here, we discuss the role of thioester-containing proteins in innate immune responses of insects. TEPs are represented by multi-member families both in the fruitfly, Drosophila melanogaster, and in the mosquito, Anopheles gambiae. Phylogenetic analysis of the family suggests that in these two dipteran species evolution of TEPs followed independent scenarios as a result of specific adaptation to distinct ecological environments. Research on these two relatively simple model systems, which lack adaptive immunity, may provide new insights into the evolutionary origins and functions of this important protein family.},
keywords = {blandin, M3i, TEP1},
pubstate = {published},
tppubtype = {article}
}
Here, we discuss the role of thioester-containing proteins in innate immune responses of insects. TEPs are represented by multi-member families both in the fruitfly, Drosophila melanogaster, and in the mosquito, Anopheles gambiae. Phylogenetic analysis of the family suggests that in these two dipteran species evolution of TEPs followed independent scenarios as a result of specific adaptation to distinct ecological environments. Research on these two relatively simple model systems, which lack adaptive immunity, may provide new insights into the evolutionary origins and functions of this important protein family.
Marco Valeria De, Stier Gunter, Blandin Stephanie A, de Marco Ario
The solubility and stability of recombinant proteins are increased by their fusion to NusA Article de journal
Dans: Biochem. Biophys. Res. Commun., vol. 322, no. 3, p. 766–771, 2004, ISSN: 0006-291X.
Résumé | Liens | BibTeX | Étiquettes: blandin, Drug Stability, Escherichia coli Proteins, Genetic Vectors, Glutathione Transferase, Kinetics, M3i, Oxidation-Reduction, Peptide Elongation Factors, Recombinant Fusion Proteins, Recombinant Proteins, Solubility, Transcription Factors, Transcriptional Elongation Factors
@article{de_marco_solubility_2004,
title = {The solubility and stability of recombinant proteins are increased by their fusion to NusA},
author = {Valeria De Marco and Gunter Stier and Stephanie A Blandin and Ario de Marco},
doi = {10.1016/j.bbrc.2004.07.189},
issn = {0006-291X},
year = {2004},
date = {2004-01-01},
journal = {Biochem. Biophys. Res. Commun.},
volume = {322},
number = {3},
pages = {766--771},
abstract = {The new bacterial vector pETM60 enables the expression of His-tagged recombinant proteins fused to the C-terminus of NusA through a TEV protease recognition sequence. Three sequences coding for two protein domains (Xklp3A and Tep3Ag) and one membrane-bound viral protein (E8R) could not be expressed in a soluble form in bacteria. Their GST-fusions were mostly soluble but quickly degraded during purification. The same sequences cloned in pETM60 were efficiently purified by metal affinity and recovered soluble after the removal of the fusion partner. The NusA-fused constructs enabled to yield 13-20mg of fusion protein per litre of culture and 2.5-5mg of pure protein per litre of culture. Structural analysis indicated that the purified proteins were monodispersed and correctly folded. NusA has been used to raise antibodies that have been successfully used for Western blot and immunoprecipitation of NusA fusion proteins.},
keywords = {blandin, Drug Stability, Escherichia coli Proteins, Genetic Vectors, Glutathione Transferase, Kinetics, M3i, Oxidation-Reduction, Peptide Elongation Factors, Recombinant Fusion Proteins, Recombinant Proteins, Solubility, Transcription Factors, Transcriptional Elongation Factors},
pubstate = {published},
tppubtype = {article}
}
The new bacterial vector pETM60 enables the expression of His-tagged recombinant proteins fused to the C-terminus of NusA through a TEV protease recognition sequence. Three sequences coding for two protein domains (Xklp3A and Tep3Ag) and one membrane-bound viral protein (E8R) could not be expressed in a soluble form in bacteria. Their GST-fusions were mostly soluble but quickly degraded during purification. The same sequences cloned in pETM60 were efficiently purified by metal affinity and recovered soluble after the removal of the fusion partner. The NusA-fused constructs enabled to yield 13-20mg of fusion protein per litre of culture and 2.5-5mg of pure protein per litre of culture. Structural analysis indicated that the purified proteins were monodispersed and correctly folded. NusA has been used to raise antibodies that have been successfully used for Western blot and immunoprecipitation of NusA fusion proteins.
Blandin Stephanie A, Shiao Shin-Hong, Moita Luis F, Janse Chris J, Waters Andrew P, Kafatos Fotis C, Levashina Elena A
Complement-like protein TEP1 is a determinant of vectorial capacity in the malaria vector Anopheles gambiae Article de journal
Dans: Cell, vol. 116, no. 5, p. 661–670, 2004, ISSN: 0092-8674.
Résumé | BibTeX | Étiquettes: Animals, Anopheles, blandin, Female, Genetic, Humans, Insect Proteins, Insect Vectors, M3i, Malaria, Models, Molecular, Plasmodium berghei, Polymorphism, Protein Structure, RNA, Sequence Alignment, Tertiary
@article{blandin_complement-like_2004,
title = {Complement-like protein TEP1 is a determinant of vectorial capacity in the malaria vector Anopheles gambiae},
author = {Stephanie A Blandin and Shin-Hong Shiao and Luis F Moita and Chris J Janse and Andrew P Waters and Fotis C Kafatos and Elena A Levashina},
issn = {0092-8674},
year = {2004},
date = {2004-01-01},
journal = {Cell},
volume = {116},
number = {5},
pages = {661--670},
abstract = {Anopheles mosquitoes are major vectors of human malaria in Africa. Large variation exists in the ability of mosquitoes to serve as vectors and to transmit malaria parasites, but the molecular mechanisms that determine vectorial capacity remain poorly understood. We report that the hemocyte-specific complement-like protein TEP1 from the mosquito Anopheles gambiae binds to and mediates killing of midgut stages of the rodent malaria parasite Plasmodium berghei. The dsRNA knockdown of TEP1 in adults completely abolishes melanotic refractoriness in a genetically selected refractory strain. Moreover, in susceptible mosquitoes this knockdown increases the number of developing parasites. Our results suggest that the TEP1-dependent parasite killing is followed by a TEP1-independent clearance of dead parasites by lysis and/or melanization. Further elucidation of the molecular mechanisms of TEP1-mediated parasite killing will be of great importance for our understanding of the principles of vectorial capacity in insects.},
keywords = {Animals, Anopheles, blandin, Female, Genetic, Humans, Insect Proteins, Insect Vectors, M3i, Malaria, Models, Molecular, Plasmodium berghei, Polymorphism, Protein Structure, RNA, Sequence Alignment, Tertiary},
pubstate = {published},
tppubtype = {article}
}
Anopheles mosquitoes are major vectors of human malaria in Africa. Large variation exists in the ability of mosquitoes to serve as vectors and to transmit malaria parasites, but the molecular mechanisms that determine vectorial capacity remain poorly understood. We report that the hemocyte-specific complement-like protein TEP1 from the mosquito Anopheles gambiae binds to and mediates killing of midgut stages of the rodent malaria parasite Plasmodium berghei. The dsRNA knockdown of TEP1 in adults completely abolishes melanotic refractoriness in a genetically selected refractory strain. Moreover, in susceptible mosquitoes this knockdown increases the number of developing parasites. Our results suggest that the TEP1-dependent parasite killing is followed by a TEP1-independent clearance of dead parasites by lysis and/or melanization. Further elucidation of the molecular mechanisms of TEP1-mediated parasite killing will be of great importance for our understanding of the principles of vectorial capacity in insects.
Blandin Stéphanie A, Levashina Elena A
Mosquito immune responses against malaria parasites Article de journal
Dans: Curr. Opin. Immunol., vol. 16, no. 1, p. 16–20, 2004, ISSN: 0952-7915.
Résumé | BibTeX | Étiquettes: Animals, Anopheles, blandin, Gene Library, Genes, Hemocytes, Host-Parasite Interactions, Immunity, Innate, Insect, Insect Vectors, M3i, Malaria, Plasmodium
@article{blandin_mosquito_2004,
title = {Mosquito immune responses against malaria parasites},
author = {Stéphanie A Blandin and Elena A Levashina},
issn = {0952-7915},
year = {2004},
date = {2004-01-01},
journal = {Curr. Opin. Immunol.},
volume = {16},
number = {1},
pages = {16--20},
abstract = {Anopheline mosquitoes are the major vectors of human malaria. Mosquito-parasite interactions are a critical aspect of disease transmission and a potential target for malaria control. Mosquitoes vary in their innate ability to support development of the malaria parasite, but the molecular mechanisms that determine vector competence are poorly understood. This area of research has been revolutionized by recent advances in the mosquito genome characterization and by the development of new tools for functional gene analysis.},
keywords = {Animals, Anopheles, blandin, Gene Library, Genes, Hemocytes, Host-Parasite Interactions, Immunity, Innate, Insect, Insect Vectors, M3i, Malaria, Plasmodium},
pubstate = {published},
tppubtype = {article}
}
Anopheline mosquitoes are the major vectors of human malaria. Mosquito-parasite interactions are a critical aspect of disease transmission and a potential target for malaria control. Mosquitoes vary in their innate ability to support development of the malaria parasite, but the molecular mechanisms that determine vector competence are poorly understood. This area of research has been revolutionized by recent advances in the mosquito genome characterization and by the development of new tools for functional gene analysis.
2003
Goto Akira, Blandin Stéphanie A, Royet Julien, Reichhart Jean-Marc, Levashina Elena A
Silencing of Toll pathway components by direct injection of double-stranded RNA into Drosophila adult flies Article de journal
Dans: Nucleic Acids Res., vol. 31, no. 22, p. 6619–6623, 2003, ISSN: 1362-4962.
Résumé | BibTeX | Étiquettes: Animals, blandin, Cell Surface, Double-Stranded, Epistasis, Female, Genetic, Green Fluorescent Proteins, Homeodomain Proteins, Luminescent Proteins, M3i, Phenotype, Receptors, reichhart, RNA, RNA Interference, Serpins, Signal Transduction, Time Factors, Toll-Like Receptors, Transcription Factors
@article{goto_silencing_2003,
title = {Silencing of Toll pathway components by direct injection of double-stranded RNA into Drosophila adult flies},
author = {Akira Goto and Stéphanie A Blandin and Julien Royet and Jean-Marc Reichhart and Elena A Levashina},
issn = {1362-4962},
year = {2003},
date = {2003-11-01},
journal = {Nucleic Acids Res.},
volume = {31},
number = {22},
pages = {6619--6623},
abstract = {Double-stranded RNA (dsRNA) gene interference is an efficient method to silence gene expression in a sequence-specific manner. Here we show that the direct injection of dsRNA can be used in adult Drosophila flies to disrupt function of endogenous genes in vivo. As a proof of principle, we have used this method to silence components of a major signaling cascade, the Toll pathway, which controls fruit fly resistance to fungal and Gram-positive bacterial infections. We demonstrate that the knockout is efficient only if dsRNA is injected in 4- or more day-old flies and that it lasts for at least 1 week. Furthermore, we report dsRNA-based epistatic gene analysis via injection of a mixture of two dsRNAs and propose that injection of dsRNA represents a powerful method for rapid functional analysis of genes in Drosophila melanogaster adults, particularly of those whose mutations are lethal during development.},
keywords = {Animals, blandin, Cell Surface, Double-Stranded, Epistasis, Female, Genetic, Green Fluorescent Proteins, Homeodomain Proteins, Luminescent Proteins, M3i, Phenotype, Receptors, reichhart, RNA, RNA Interference, Serpins, Signal Transduction, Time Factors, Toll-Like Receptors, Transcription Factors},
pubstate = {published},
tppubtype = {article}
}
Double-stranded RNA (dsRNA) gene interference is an efficient method to silence gene expression in a sequence-specific manner. Here we show that the direct injection of dsRNA can be used in adult Drosophila flies to disrupt function of endogenous genes in vivo. As a proof of principle, we have used this method to silence components of a major signaling cascade, the Toll pathway, which controls fruit fly resistance to fungal and Gram-positive bacterial infections. We demonstrate that the knockout is efficient only if dsRNA is injected in 4- or more day-old flies and that it lasts for at least 1 week. Furthermore, we report dsRNA-based epistatic gene analysis via injection of a mixture of two dsRNAs and propose that injection of dsRNA represents a powerful method for rapid functional analysis of genes in Drosophila melanogaster adults, particularly of those whose mutations are lethal during development.
2002
Christophides George K, Zdobnov Evgeny, Barillas-Mury Carolina, Birney Ewan, Blandin Stephanie A, Blass Claudia, Brey Paul T, Collins Frank H, Danielli Alberto, Dimopoulos George, Hetru Charles, Hoa Ngo T, Hoffmann Jules A, Kanzok Stefan M, Letunic Ivica, Levashina Elena A, Loukeris Thanasis G, Lycett Gareth, Meister Stephan, Michel Kristin, Moita Luis F, Müller Hans-Michael, Osta Mike A, Paskewitz Susan M, Reichhart Jean-Marc, Rzhetsky Andrey, Troxler Laurent, Vernick Kenneth D, Vlachou Dina, Volz Jennifer, von Mering Christian, Xu Jiannong, Zheng Liangbiao, Bork Peer, Kafatos Fotis C
Immunity-related genes and gene families in Anopheles gambiae Article de journal
Dans: Science, vol. 298, no. 5591, p. 159–165, 2002, ISSN: 1095-9203.
Résumé | Liens | BibTeX | Étiquettes: Alternative Splicing, Animals, Anopheles, Apoptosis, bacteria, bioinformatic, blandin, Catechol Oxidase, Computational Biology, Enzyme Precursors, Gene Expression Regulation, Genes, Genetic, Genome, hoffmann, Immunity, Innate, Insect, Insect Proteins, M3i, Multigene Family, Peptides, Phylogeny, Plasmodium, Protein Structure, reichhart, Selection, Serine Endopeptidases, Serpins, Signal Transduction, Tertiary
@article{christophides_immunity-related_2002,
title = {Immunity-related genes and gene families in Anopheles gambiae},
author = {George K Christophides and Evgeny Zdobnov and Carolina Barillas-Mury and Ewan Birney and Stephanie A Blandin and Claudia Blass and Paul T Brey and Frank H Collins and Alberto Danielli and George Dimopoulos and Charles Hetru and Ngo T Hoa and Jules A Hoffmann and Stefan M Kanzok and Ivica Letunic and Elena A Levashina and Thanasis G Loukeris and Gareth Lycett and Stephan Meister and Kristin Michel and Luis F Moita and Hans-Michael Müller and Mike A Osta and Susan M Paskewitz and Jean-Marc Reichhart and Andrey Rzhetsky and Laurent Troxler and Kenneth D Vernick and Dina Vlachou and Jennifer Volz and Christian von Mering and Jiannong Xu and Liangbiao Zheng and Peer Bork and Fotis C Kafatos},
url = {http://www.ncbi.nlm.nih.gov/pubmed/12364793},
doi = {10.1126/science.1077136},
issn = {1095-9203},
year = {2002},
date = {2002-10-01},
journal = {Science},
volume = {298},
number = {5591},
pages = {159--165},
abstract = {We have identified 242 Anopheles gambiae genes from 18 gene families implicated in innate immunity and have detected marked diversification relative to Drosophila melanogaster. Immune-related gene families involved in recognition, signal modulation, and effector systems show a marked deficit of orthologs and excessive gene expansions, possibly reflecting selection pressures from different pathogens encountered in these insects' very different life-styles. In contrast, the multifunctional Toll signal transduction pathway is substantially conserved, presumably because of counterselection for developmental stability. Representative expression profiles confirm that sequence diversification is accompanied by specific responses to different immune challenges. Alternative RNA splicing may also contribute to expansion of the immune repertoire.},
keywords = {Alternative Splicing, Animals, Anopheles, Apoptosis, bacteria, bioinformatic, blandin, Catechol Oxidase, Computational Biology, Enzyme Precursors, Gene Expression Regulation, Genes, Genetic, Genome, hoffmann, Immunity, Innate, Insect, Insect Proteins, M3i, Multigene Family, Peptides, Phylogeny, Plasmodium, Protein Structure, reichhart, Selection, Serine Endopeptidases, Serpins, Signal Transduction, Tertiary},
pubstate = {published},
tppubtype = {article}
}
We have identified 242 Anopheles gambiae genes from 18 gene families implicated in innate immunity and have detected marked diversification relative to Drosophila melanogaster. Immune-related gene families involved in recognition, signal modulation, and effector systems show a marked deficit of orthologs and excessive gene expansions, possibly reflecting selection pressures from different pathogens encountered in these insects' very different life-styles. In contrast, the multifunctional Toll signal transduction pathway is substantially conserved, presumably because of counterselection for developmental stability. Representative expression profiles confirm that sequence diversification is accompanied by specific responses to different immune challenges. Alternative RNA splicing may also contribute to expansion of the immune repertoire.
Blandin Stéphanie A, Moita L F, Kocher T, Wilm M, Kafatos Fotis C, Levashina Elena A
Reverse genetics in the mosquito, Anopheles gambiae : targeted disruption of the Defensin gene Article de journal
Dans: EMBO Rep., vol. 3, no. 9, p. 852-6, 2002.
Résumé | Liens | BibTeX | Étiquettes: blandin, defensin, M3i
@article{S2002,
title = {Reverse genetics in the mosquito, Anopheles gambiae : targeted disruption of the Defensin gene},
author = {Stéphanie A Blandin and L F Moita and T Kocher and M Wilm and Fotis C Kafatos and Elena A Levashina},
url = {http://www.ncbi.nlm.nih.gov/pubmed/12189180},
year = {2002},
date = {2002-09-02},
journal = {EMBO Rep.},
volume = {3},
number = {9},
pages = {852-6},
abstract = {Anopheles gambiae, the major vector of human malaria parasite, is an important insect model to study vector-parasite interactions. Here, we developed a simple in vivo double-stranded RNA (dsRNA) knockout approach to determine the function of the mosquito antimicrobial peptide gene Defensin. We injected dsRNA into adults and observed efficient and reproducible silencing of Defensin. Analysis of the knockdown phenotype revealed that this peptide is required for the mosquito antimicrobial defense against Gram-positive bacteria. In contrast, in mosquitoes infected by Plasmodium berghei, no loss of mosquito viability and no significant effect on the development and morphology of the parasite midgut stages were observed in the absence of Defensin. We conclude that this peptide is not a major antiparasitic factor in A. gambiae in vivo. Our results open new perspectives for the study of mosquito gene function in vivo and provide a basis for genome-scale systematic functional screens by targeted gene silencing.},
keywords = {blandin, defensin, M3i},
pubstate = {published},
tppubtype = {article}
}
Anopheles gambiae, the major vector of human malaria parasite, is an important insect model to study vector-parasite interactions. Here, we developed a simple in vivo double-stranded RNA (dsRNA) knockout approach to determine the function of the mosquito antimicrobial peptide gene Defensin. We injected dsRNA into adults and observed efficient and reproducible silencing of Defensin. Analysis of the knockdown phenotype revealed that this peptide is required for the mosquito antimicrobial defense against Gram-positive bacteria. In contrast, in mosquitoes infected by Plasmodium berghei, no loss of mosquito viability and no significant effect on the development and morphology of the parasite midgut stages were observed in the absence of Defensin. We conclude that this peptide is not a major antiparasitic factor in A. gambiae in vivo. Our results open new perspectives for the study of mosquito gene function in vivo and provide a basis for genome-scale systematic functional screens by targeted gene silencing.
Levashina Elena A, Blandin Stéphanie A, Moita L F, Lagueux Marie, Kafatos Fotis C
Thioester-Containing Proteins of Protostomes Chapitre d'ouvrage
Dans: Ezekowitz, Alan R B; Hoffmann, Jules A (Ed.): Chapitre Infectious Disease: Innate Immunity., p. 155-173, Humana Press Inc, Totowa, NJ, 2002.
BibTeX | Étiquettes: blandin, M3i, Thioester-Containing Protein
@inbook{EA2002,
title = {Thioester-Containing Proteins of Protostomes},
author = {Elena A Levashina and Stéphanie A Blandin and L F Moita and Marie Lagueux and Fotis C Kafatos},
editor = {Alan R B Ezekowitz and Jules A Hoffmann},
year = {2002},
date = {2002-06-08},
pages = {155-173},
publisher = {Humana Press Inc, Totowa, NJ},
chapter = {Infectious Disease: Innate Immunity.},
keywords = {blandin, M3i, Thioester-Containing Protein},
pubstate = {published},
tppubtype = {inbook}
}
2001
Levashina Elena A, Moita L F, Blandin Stéphanie A, Vriend G, Lagueux Marie, Kafatos F C
Conserved role of a complement-like protein in phagocytosis revealed by dsRNA knockout in cultured cells of the mosquito, Anopheles gambiae Article de journal
Dans: Cell, vol. 104, no. 5, p. 709–718, 2001, ISSN: 0092-8674.
Résumé | BibTeX | Étiquettes: alpha-Macroglobulins, Animals, Anopheles, blandin, Cells, Cloning, Complement C3, Cultured, DNA Fragmentation, Double-Stranded, Female, Genetic, Gram-Negative Bacteria, Hemocytes, Insect Proteins, M3i, Molecular, Nucleic Acid Denaturation, Phagocytosis, Protein Structure, RNA, Tertiary, Transcription
@article{levashina_conserved_2001,
title = {Conserved role of a complement-like protein in phagocytosis revealed by dsRNA knockout in cultured cells of the mosquito, Anopheles gambiae},
author = {Elena A Levashina and L F Moita and Stéphanie A Blandin and G Vriend and Marie Lagueux and F C Kafatos},
issn = {0092-8674},
year = {2001},
date = {2001-01-01},
journal = {Cell},
volume = {104},
number = {5},
pages = {709--718},
abstract = {We characterize a novel hemocyte-specific acute phase glycoprotein from the malaria vector, Anopheles gambiae. It shows substantial structural and functional similarities, including the highly conserved thioester motif, to both a central component of mammalian complement system, factor C3, and to a pan-protease inhibitor, alpha2-macroglobulin. Most importantly, this protein serves as a complement-like opsonin and promotes phagocytosis of some Gram-negative bacteria in a mosquito hemocyte-like cell line. Chemical inactivation by methylamine and depletion by double-stranded RNA knockout demonstrate that this function is dependent on the internal thioester bond. This evidence of a complement-like function in a protostome animal adds substantially to the accumulating evidence of a common ancestry of immune defenses in insects and vertebrates.},
keywords = {alpha-Macroglobulins, Animals, Anopheles, blandin, Cells, Cloning, Complement C3, Cultured, DNA Fragmentation, Double-Stranded, Female, Genetic, Gram-Negative Bacteria, Hemocytes, Insect Proteins, M3i, Molecular, Nucleic Acid Denaturation, Phagocytosis, Protein Structure, RNA, Tertiary, Transcription},
pubstate = {published},
tppubtype = {article}
}
We characterize a novel hemocyte-specific acute phase glycoprotein from the malaria vector, Anopheles gambiae. It shows substantial structural and functional similarities, including the highly conserved thioester motif, to both a central component of mammalian complement system, factor C3, and to a pan-protease inhibitor, alpha2-macroglobulin. Most importantly, this protein serves as a complement-like opsonin and promotes phagocytosis of some Gram-negative bacteria in a mosquito hemocyte-like cell line. Chemical inactivation by methylamine and depletion by double-stranded RNA knockout demonstrate that this function is dependent on the internal thioester bond. This evidence of a complement-like function in a protostome animal adds substantially to the accumulating evidence of a common ancestry of immune defenses in insects and vertebrates.
