M3i

@article{dieker_apoptosis-linked_2008,

title = {Apoptosis-linked changes in the phosphorylation status and subcellular localization of the spliceosomal autoantigen U1-70K},

author = {J Dieker and B Cisterna and F Monneaux and M Decossas and J van der Vlag and M Biggiogera and S Muller},

doi = {10.1038/sj.cdd.4402312},

issn = {1350-9047},

year  = {2008},

date = {2008-01-01},

journal = {Cell Death and Differentiation},

volume = {15},

number = {4},

pages = {793--804},

abstract = {Apoptosis consists of highly regulated pathways involving post-translational modifications and cleavage of proteins leading to sequential inactivation of the main cellular processes. Here, we focused on the apoptotic processing of one of the essential components of the mRNA splicing machinery, the U1-70K snRNP protein. We found that at an early stage of apoptosis, before the cleavage of the C-terminal part of the protein by caspase-3, the basal phosphorylation of the Ser140 residue located within the RNA recognition motif, increases very significantly. A caspase-dependent, PP1-mediated dephosphorylation of other serine residues takes place in a subset of U1-70K proteins. The U1-70K protein phosphorylated at Ser140 is clustered in heterogeneous ectopic RNP-derived structures, which are finally extruded in apoptotic bodies. The elaborate processing of the spliceosomal U1-70K protein we identified might play an important role in the regulated breakdown of the mRNA splicing machinery during early apoptosis. In addition, these specific changes in the phosphorylation/dephosphorylation balance and the subcellular localization of the U1-70K protein might explain why the region encompassing the Ser140 residue becomes a central autoantigen during the autoimmune disease systemic lupus erythematosus.},

keywords = {Apoptosis, Autoantigens, Autoimmunity, Caspase 3, Chromatin, HeLa Cells, Humans, I2CT, Jurkat Cells, Lupus Erythematosus, Monneaux, Phosphorylation, Post-Translational, Protein Phosphatase 1, Protein Processing, Protein Transport, Recombinant Proteins, Ribonucleoprotein, RNA Splicing, Serine, Spliceosomes, Systemic, Team-Dumortier, Time Factors, U1 Small Nuclear},

pubstate = {published},

tppubtype = {article}

}

@article{monneaux_spliceosome_2007,

title = {[The spliceosome and its interest for lupus therapy]},

author = {F Monneaux and S Muller},

doi = {10.1016/j.revmed.2007.05.003},

issn = {0248-8663},

year  = {2007},

date = {2007-01-01},

journal = {La Revue De Medecine Interne},

volume = {28},

number = {10},

pages = {725--728},

abstract = {INTRODUCTION: The spliceosome, which is a particle containing a molecule of U-RNA and proteins that are specific to each U ribonuclear particle (U-snRNP) or common to every U-snRNPs, is one of the numerous nuclear targets recognized by the antibodies (Abs) and CD4+ T cells from patients with systemic lupus erythematosus and lupus mice. 

EXEGESIS: We recently characterized a peptide from the spliceosomal protein U1-70K (sequence 131-151), which is recognized by the Abs and CD4+ T cells from lupus mice and patients. This peptide contains a conserved RNP1 motif, which is also present in other spliceosomal proteins targeted by the Abs from individuals with lupus. We further showed that peptide 131-151 containing a phosphoserine at position 140 (peptide P140) possessed tolerogenic properties in lupus mice and was recognized by the Abs and CD4+ T cells from lupus patients. 

CONCLUSION: Thanks to its RNP1 motif, the peptide P140 might play an important role in the initiation and perpetuation steps of the humoral and cellular immune response diversification in lupus individuals. Therapeutic and particularly immunomodulating properties of P140 peptide are being evaluated in humans (a phase III clinical trial will be undertaken in the next weeks).},

keywords = {Amino Acid Motifs, Animals, Antibodies, CD4-Positive T-Lymphocytes, Conserved Sequence, DNA, Epitopes, Haplotypes, Humans, I2CT, Immune Tolerance, Inbred MRL lpr, Inbred NZB, Lupus Erythematosus, Mice, Monneaux, Phosphoserine, Protein, Recombinant, Ribonucleoprotein, Sequence Analysis, Serine, Spliceosomes, Systemic, Team-Dumortier, U1 Small Nuclear},

pubstate = {published},

tppubtype = {article}

}