title: Hyper-O-GlcNAcylation inhibits the induction of heat shock protein 70 (Hsp 70) by sodium arsenite in HeLa cells.
abstract: O-Linked β-N-acetylglucosamine-modification (O-GlcNAcylation) is a reversible, post-translational, and regulatory modification of nuclear, mitochondrial, and cytoplasmic proteins that is responsive to cellular stress. However, the role of O-GlcNAcylation in the induction of heat shock proteins (Hsps) by arsenite remains unclear. We used O-(2-acetamido-2-deoxy-D-glucopyranosylidene) amino N-phenyl carbamate (PUGNAc), an inhibitor of O-GlcNAcase, and glucosamine (GlcN), an enhancer of the hexosamine biosynthesis pathway, or O-GlcNAc transferase (OGT) short interfering RNA (siRNA) to enhance or suppress cellular O-GlcNAcylation levels, respectively, in HeLa cells. The exposure to arsenite increased O-GlcNAcylation and Hsp 70 levels in HeLa cells. However, the pre-treatment with PUGNAc or GlcN, which enhanced O-GlcNAcylation levels, decreased the arsenite-induced expression of Hsp 70. The pre-treatment with OGT siRNA, which suppressed O-GlcNAcylation levels, did not affect the induction of Hsp 70. We then examined the effects of O-GlcNAcylation on the nuclear translocation and phosphorylation of heat shock factor 1 (HSF1), and found that neither the nuclear translocation nor phosphorylation of HSF1 was regulated by O-GlcNAcylation. Finally, Hsp 70 mRNA expression was induced by arsenite, whereas the addition of PUGNAc slightly suppressed its induction. These results indicate that O-GlcNAcylation is related to arsenite-induced Hsp 70 expression, and demonstrated that hyper-O-GlcNAcylation inhibited the induction of Hsp 70 via transcriptional factors instead of HSF1.
authors.affiliation: Research Team for Mechanism of Aging, Tokyo Metropolitan Institute of Gerontology.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Miura
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Sato
authors.forename: Yoko
authors.initials: Y
authors.lastname: Sakurai
authors.forename: Ryo
authors.initials: R
authors.lastname: Sakai
authors.forename: Wakako
authors.initials: W
authors.lastname: Hiraoka
authors.forename: Tamao
authors.initials: T
authors.lastname: Endo
mesh_terms: D000117:Acetylglucosamine / Q000031:analogs & derivatives / Q000494:pharmacology; D000215:Acylation; D018053:Arsenites / Q000633:toxicity*; D004268:DNA-Binding Proteins / Q000378:metabolism; D005944:Glucosamine / Q000494:pharmacology; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D000076249:Heat Shock Transcription Factors; D006801:Humans; D017351:N-Acetylglucosaminyltransferases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects; D010091:Oximes / Q000494:pharmacology; D048448:Phenylcarbamates / Q000494:pharmacology; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D017670:Sodium Compounds / Q000633:toxicity*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D018053:Arsenites; D004268:DNA-Binding Proteins; C000619706:HSF1 protein, human; D018840:HSP70 Heat-Shock Proteins; D000076249:Heat Shock Transcription Factors; D010091:Oximes; D048448:Phenylcarbamates; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D017670:Sodium Compounds; D014157:Transcription Factors; C068836:N-acetylglucosaminono-1,5-lactone O-(phenylcarbamoyl)oxime; C017947:sodium arsenite; D017351:N-Acetylglucosaminyltransferases; C449880:O-GlcNAc transferase; D005944:Glucosamine; D000117:Acetylglucosamine