title: Evidence of the involvement of O-GlcNAc-modified human RNA polymerase II CTD in transcription in vitro and in vivo.
abstract: The RNA polymerase II C-terminal domain (CTD), which serves as a scaffold to recruit machinery involved in transcription, is modified post-translationally. Although the O-GlcNAc modification of RNA polymerase II CTD was documented in 1993, its functional significance remained obscure. We show that O-GlcNAc transferase (OGT) modified CTD serine residues 5 and 7. Drug inhibition of OGT and OGA (N-acetylglucosaminidase) blocked transcription during preinitiation complex assembly. Polymerase II and OGT co-immunoprecipitated, and OGT is a component of the preinitiation complex. OGT shRNA experiments showed that reduction of OGT causes a reduction in transcription and RNA polymerase II occupancy at several B-cell promoters. These data suggest that the cycling of O-GlcNAc on and off of polymerase II occurs during assembly of the preinitiation complex. Our results define unexpected roles for both the CTD and O-GlcNAc in the regulation of transcription initiation in higher eukaryotes.
authors.affiliation: Metabolism Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA
authors.forename: Stella M
authors.initials: SM
authors.lastname: Ranuncolo
authors.forename: Salil
authors.initials: S
authors.lastname: Ghosh
authors.forename: John A
authors.initials: JA
authors.lastname: Hanover
authors.forename: Gerald W
authors.initials: GW
authors.lastname: Hart
authors.forename: Brian A
authors.initials: BA
authors.lastname: Lewis
mesh_terms: D000117:Acetylglucosamine / Q000031:analogs & derivatives / Q000378:metabolism* / Q000494:pharmacology; D000118:Acetylglucosaminidase / Q000037:antagonists & inhibitors / Q000378:metabolism; D001665:Binding Sites; D015153:Blotting, Western; D045744:Cell Line, Tumor; D047369:Chromatin Immunoprecipitation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D017351:N-Acetylglucosaminyltransferases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D010091:Oximes / Q000494:pharmacology; D048448:Phenylcarbamates / Q000494:pharmacology; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D021122:Protein Subunits / Q000378:metabolism; D034622:RNA Interference; D012319:RNA Polymerase II / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012694:Serine / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects / Q000235:genetics*
chemical_list: D004791:Enzyme Inhibitors; D010091:Oximes; D048448:Phenylcarbamates; D021122:Protein Subunits; C068836:N-acetylglucosaminono-1,5-lactone O-(phenylcarbamoyl)oxime; D012694:Serine; D017351:N-Acetylglucosaminyltransferases; C449880:O-GlcNAc transferase; D012319:RNA Polymerase II; D000118:Acetylglucosaminidase; D000117:Acetylglucosamine