Yeast TAF(II)90 is required for cell-cycle progression through G2/M but not for general transcription activation
UMass Chan AffiliationsProgram in Gene Function and Expression
Program in Molecular Medicine
Graduate School of Biomedical Sciences
KeywordsAlleles; Amino Acid Sequence; Bacterial Proteins; Cell Cycle; DNA-Binding Proteins; G2 Phase; Gene Expression Regulation, Fungal; Mitosis; Molecular Sequence Data; Mutation; Phenotype; RNA Polymerase II; Recombinant Fusion Proteins; *Saccharomyces cerevisiae Proteins; Serine Endopeptidases; *TATA-Binding Protein Associated Factors; TATA-Box Binding Protein; Temperature; *Trans-Activation (Genetics); Transcription Factors; Transcription, Genetic; Yeasts
Medicine and Health Sciences
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AbstractThe RNA polymerase II general transcription factor TFIID is a multisubunit complex comprising TATA-box binding protein and associated factors (TAFIIs). In vitro experiments have suggested that TAFIIs are essential coactivators required for RNA polymerase II-directed transcription activation. Here, for the first time, we analyze systematically the in vivo function of a specific TAFII, yeast TAFII90 (yTAFII90). We show that functional inactivation of yTAFII90 by temperature-sensitive mutations or depletion leads to arrest at the G2/M phase of the cell cycle. Unexpectedly, in the absence of functional yTAFII90, a variety of endogenous yeast genes were all transcribed normally, including those driven by well-characterized activators. Taken together, our results indicate that yTAFII90 is not required for transcription activation in general, and reveal linkages between TAF function and cell-cycle progression.
Genes Dev. 1996 Sep 15;10(18):2368-80.
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/33842
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