Cooperation between small nuclear RNA-activating protein complex (SNAPC) and TATA-box-binding protein antagonizes protein kinase CK2 inhibition of DNA binding by SNAPC.
Protein kinase CK2 regulates RNA polymerase III transcription of human U6 small nuclear RNA (snRNA) genes both negatively and positively depending upon whether the general transcription machinery or RNA polymerase III is preferentially phosphorylated. Human U1 snRNA genes share similar promoter architectures as that of U6 genes but are transcribed by RNA polymerase II. Herein, we report that CK2 inhibits U1 snRNA gene transcription by RNA polymerase II. Decreased levels of endogenous CK2 correlates with increased U1 expression, whereas CK2 associates with U1 gene promoters, indicating that it plays a direct role in U1 gene regulation. CK2 phosphorylates the general transcription factor small nuclear RNA-activating protein complex (SNAP(C)) that is required for both RNA polymerase II and III transcription, and SNAP(C) phosphorylation inhibits binding to snRNA gene promoters. However, restricted promoter access by phosphorylated SNAP(C) can be overcome by cooperative interactions with TATA-box-binding protein at a U6 promoter but not at a U1 promoter. Thus, CK2 may have the capacity to differentially regulate U1 and U6 transcription even though SNAP(C) is universally utilized for human snRNA gene transcription.
Gu
Liping
L
Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824, USA.
Esselman
Walter J
WJ
Henry
R William
RW
D001665:Binding Sites; D047390:Casein Kinase II / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D047369:Chromatin Immunoprecipitation; D002855:Chromatography, Thin Layer; D004247:DNA / Q000737:chemistry; D006367:HeLa Cells; D006801:Humans; D047468:Immunoprecipitation; D010455:Peptides / Q000737:chemistry; D010766:Phosphorylation; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D012319:RNA Polymerase II / Q000378:metabolism; D012342:RNA, Small Nuclear / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry; D035181:TATA-Box Binding Protein / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D014158:Transcription, Genetic; D014357:Trypsin / Q000494:pharmacology
D010455:Peptides; D012342:RNA, Small Nuclear; D011994:Recombinant Proteins; C106703:SNAPC protein complex, human; D035181:TATA-Box Binding Protein; D014157:Transcription Factors; D004247:DNA; D047390:Casein Kinase II; D012319:RNA Polymerase II; D014357:Trypsin