title: Human RNA Polymerase II Promoter Recruitment in Vitro Is Regulated by O-Linked N-Acetylglucosaminyltransferase (OGT).
abstract: Although the O-linked N-acetylglucosamine (O-GlcNAc) modification of the RNA polymerase II C-terminal domain was described 20 years ago, the function of this RNA polymerase II (pol II) species is not known. We show here that an O-GlcNAcylated pol II species (pol IIγ) exists on promoters in vitro Inhibition of O-GlcNAc-transferase activity and O-GlcNAcylation prevents pol II entry into the promoter, and O-GlcNAc removal from pol II is an ATP-dependent step during initiation. These data indicate that O-GlcNAc-transferase activity is essential for RNA pol II promoter recruitment and that pol II goes through a cycling of O-GlcNAcylation at the promoter. Mass spectrometry shows that serine residues 2 and 5 of the pol II C-terminal domain are O-GlcNAcylated, suggesting an overlap with the transcription factor IIH (TFIIH)-dependent serine 5 phosphorylation events during initiation and P-TEFb (positive transcriptional elongation factor b) events during elongation. These data provide unexpected and important insights into the role of a previously ill-defined species of RNA polymerase II in regulating transcription.
authors.affiliation: Transcriptional Regulation and Biochemistry Unit, Metabolism Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892. Electronic address: lewisbri@mail.nih.gov.
authors.forename: Brian A
authors.initials: BA
authors.lastname: Lewis
authors.affiliation: Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94158.
authors.forename: Alma L
authors.initials: AL
authors.lastname: Burlingame
authors.affiliation: Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94158.
authors.forename: Samuel A
authors.initials: SA
authors.lastname: Myers
mesh_terms: D006801:Humans; D066298:In Vitro Techniques; D017351:N-Acetylglucosaminyltransferases / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D012319:RNA Polymerase II / Q000235:genetics*
chemical_list: D017351:N-Acetylglucosaminyltransferases; D012319:RNA Polymerase II
keywords: O-GlcNAcylation; O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT); RNA polymerase II; gene regulation; transcription