NAT, a human complex containing Srb polypeptides that functions as a negative regulator of activated transcription.
A complex that represses activated transcription and contains the human homologs of the yeast Srb7, Srb10, Srb11, Rgr1, and Med6 proteins was isolated. The complex is devoid of the Srb polypeptides previously shown to be components of the yeast Mediator complex that functions in transcriptional activation. The complex phosphorylates the CTD of RNA polymerase II (RNAPII) at residues other than those phosphorylated by the kinase of TFIIH. Moreover, the complex specifically interacts with RNAPII. The interaction is not mediated by the CTD of RNAPII, but is precluded by phosphorylation of the CTD. Our results indicate that the complex is a subcomplex of the human RNAPII holoenzyme. We suggest that the RNAPII holoenzyme is a transcriptional control panel, integrating and responding to specific signals to activate or repress transcription.
Sun
X
X
Howard Hughes Medical Institute, Department of Biochemistry, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway 08854-5635, USA.
Zhang
Y
Y
Cho
H
H
Rickert
P
P
Lees
E
E
Lane
W
W
Reinberg
D
D
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018844:Cyclin-Dependent Kinases; D016213:Cyclins; D018076:DNA, Complementary / Q000235:genetics; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006801:Humans; D046911:Macromolecular Substances; D056892:Mediator Complex; D008969:Molecular Sequence Data; D010766:Phosphorylation; D012319:RNA Polymerase II / Q000378:metabolism; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D015534:Trans-Activators; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D015533:Transcriptional Activation
D016213:Cyclins; D018076:DNA, Complementary; D005656:Fungal Proteins; C098617:MED21 protein, human; C491485:MED6 protein, human; D046911:Macromolecular Substances; D056892:Mediator Complex; C095061:RGR1 protein, S cerevisiae; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C093345:SSN8 protein, S cerevisiae; D018844:Cyclin-Dependent Kinases; D012319:RNA Polymerase II