title: Quantitative proteomics and dynamic imaging reveal that G3BP-mediated stress granule assembly is poly(ADP-ribose)-dependent following exposure to MNNG-induced DNA alkylation.
abstract: Poly(ADP-ribose) (pADPr) is a heterogenic molecule synthesised from NAD by poly(ADP-ribose) polymerases (PARPs). Many cellular functions from genome integrity surveillance, cell cycle progression and DNA repair to apoptosis are affected by pADPr through its network of associated proteins. Using quantitative proteomics, we established a temporal map of pADPr-associated complexes upon genotoxic stress. Results suggested a strong pADPr association to many proteins involved in stress granule formation, notably the ras-GAP SH3-binding protein G3BP, as well as in the later phases of alkylation-stress-induced responses. Further investigation with dynamic imaging clearly demonstrated a pADPr-dependent initiation of stress granule assembly originating from the nucleus. The co-transfection of G3BP with poly(ADP-ribose) glycohydrolase (PARG) indicates that pADPr is involved in modulating the nuclear translocation of G3BP. Moreover, a peptide pADPr blot assay of G3BP revealed that pADPr binds to the glycine-arginine-rich domain of G3BP. Thereafter, we established a comprehensive G3BP interactome in the presence of pADPr. Our findings establish a novel function for pADPr in the formation of G3BP-induced stress granules upon genotoxic stress.
authors: Centre de recherche du CHUQ, Laval University, Cancer Department, Québec,  Canada.
authors: Maxim
authors: M
authors: Isabelle
authors: Jean-Philippe
authors: JP
authors: Gagné
authors: Imed-Eddine
authors: IE
authors: Gallouzi
authors: Guy G
authors: GG
authors: Poirier
mesh_terms: D000478:Alkylation / Q000187:drug effects; D000595:Amino Acid Sequence; D015153:Blotting, Western; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D016000:Cluster Analysis; D003594:Cytoplasmic Granules / Q000187:drug effects / Q000378:metabolism*; D004247:DNA / Q000378:metabolism*; D004249:DNA Damage; D004265:DNA Helicases; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007553:Isotope Labeling; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology; D008969:Molecular Sequence Data; D011064:Poly Adenosine Diphosphate Ribose / Q000378:metabolism*; D000075223:Poly-ADP-Ribose Binding Proteins; D011485:Protein Binding / Q000187:drug effects; D017434:Protein Structure, Tertiary; D021381:Protein Transport / Q000187:drug effects; D040901:Proteomics / Q000379:methods*; D020365:RNA Helicases; D000067776:RNA Recognition Motif Proteins; D015203:Reproducibility of Results; D013312:Stress, Physiological / Q000187:drug effects; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism; D013997:Time Factors
chemical_list: D002352:Carrier Proteins; D005231:Fatty Acids, Unsaturated; D000075223:Poly-ADP-Ribose Binding Proteins; D000067776:RNA Recognition Motif Proteins; D008769:Methylnitronitrosoguanidine; D049452:Green Fluorescent Proteins; D011064:Poly Adenosine Diphosphate Ribose; D004247:DNA; D004265:DNA Helicases; C116070:G3BP1 protein, human; D020365:RNA Helicases; C038753:leptomycin B