Abstract:
:Activation of eukaryotic class II gene expression involves the formation of a transcription initiation complex that includes RNA polymerase II, general transcription factors, and SRB components of the holoenzyme. Negative regulators of transcription have been described, but it is not clear whether any are general repressors of class II genes in vivo. We reasoned that defects in truly global negative regulators should compensate for deficiencies in SRB4 because SRB4 plays a positive role in holoenzyme function. Genetic experiments reveal that this is indeed the case: a defect in the yeast homologue of the human negative regulator NC2 (Dr1 x DRAP1) suppresses a mutation in SRB4. Global defects in mRNA synthesis caused by the defective yeast holoenzyme are alleviated by the NC2 suppressing mutation in vivo, indicating that yeast NC2 is a global negative regulator of class II transcription. These results imply that relief from repression at class II promoters is a general feature of gene activation in vivo.
journal_name
Proc Natl Acad Sci U S Aauthors
Gadbois EL,Chao DM,Reese JC,Green MR,Young RAdoi
10.1073/pnas.94.7.3145subject
Has Abstractpub_date
1997-04-01 00:00:00pages
3145-50issue
7eissn
0027-8424issn
1091-6490journal_volume
94pub_type
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