Yeast Ume6p repressor permits activator binding but restricts TBP binding at the HOP1 promoter.
Ume6p plays essential roles in the regulation of early meiotic genes in Saccharomyces cerevisiae. Ume6p exerts repression via recruitment of the Sin3p-Rpd3p histone deacetylase and Isw2p chromatin remodeling complexes. The transcriptional step that is ultimately inhibited by Ume6p is unknown. Here, in vivo footprinting shows that transcriptional activators Hap1p and Abf1p occupy upstream sites in repressed and derepressed promoters. In contrast, chromatin immunoprecipitation shows that TATA box-binding protein (TBP)- promoter binding is reduced upon repression of HOP1. Fusion of TBP to a zinc cluster DNA binding domain relieves repression at a HOP1 promoter modified to include the zinc cluster target site. We suggest that TBP binding is inhibited through chromatin modification by the Sin3p-Rpd3p and Isw2p complexes recruited by Ume6p.
Shimizu
Mitsuhiro
M
Department of Chemistry, Meisei University, Hino, Tokyo 191-8506, Japan. shimizum@chem.meisei-u.ac.jp
Takahashi
Keiko
K
Lamb
Teresa M
TM
Shindo
Heisaburo
H
Mitchell
Aaron P
AP
D001665:Binding Sites; D002843:Chromatin / Q000378:metabolism; D003574:Cytochrome c Group / Q000235:genetics; D045304:Cytochromes c; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D015966:Gene Expression Regulation, Fungal; D008957:Models, Genetic; D011233:Precipitin Tests; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012097:Repressor Proteins / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D035181:TATA-Box Binding Protein / Q000378:metabolism*; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism / Q000502:physiology*
C061886:ABF1 protein, S cerevisiae; C014059:CYC1 protein, S cerevisiae; D002843:Chromatin; D003574:Cytochrome c Group; D004268:DNA-Binding Proteins; C058452:HAP1 protein, S cerevisiae; C086672:HOP1 protein, S cerevisiae; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D035181:TATA-Box Binding Protein; D015534:Trans-Activators; D014157:Transcription Factors; C089979:UME6 protein, S cerevisiae; D045304:Cytochromes c