YEAST TAF(II)145 REQUIRED FOR TRANSCRIPTION OF G1 S CYCLIN GENES AND REGULATED BY THE CELLULAR GROWTH-STATE/

TFIID comprises the TATA box-binding protein and a set of highly conse rved associated factors (TAF(II)s). yTAF(II)145, the core subunit of t he yeast TAF(II) complex, is dispensable for transcription of most yea st genes but specifically required for progression through G1/S. Here we show that transcription of G1 and certain B-type cyclin genes is de pendent upon yTAF(II)145. At high cell density or following nutrient d eprivation, yeast cells cease division, enter a G(0)-like state, and t erminate transcription of most genes. In this stationary phase, we fin d that the levels of yTAF(II)145, several other yTAF(II)s, and TBP are drastically reduced. Collectively, our results indicate that yTAF(II) 145 and other TFIID components have a specialized role in transcriptio nal regulation of cell cycle progression and growth control.