Transcriptional repression by Tup1-Ssn6.
The Tup1-Ssn6 complex from budding yeast is one of the best studied corepressors and has served as a model for the study of similar corepressor complexes in higher eukaryotes. Tup1-Ssn6 represses multiple subsets of genes when recruited to promoters by sequence-specific DNA binding repressors. Tup1-Ssn6 mediated repression involves interactions among the corepressor and hypoacetylated histones, histone deacetylases, and the RNA transcriptional machinery. Nucleosome positioning is also involved in repression of a subset of Tup1-Ssn6 regulated genes. These findings highlight the importance of chromatin modification states in Tup1-Ssn6 mediated repression. Here we review the multiple mechanisms involved in repression and discuss Tup1-Ssn6 homolog functions in higher organisms. We also present a model for how repression by Tup1-Ssn6 may be established.
Malavé
Tania M
TM
Department of Biochemistry and Molecular Biology, U.T. M.D. Anderson Cancer Center, Houston, TX 77030, USA.
Dent
Sharon Y R
SY
D004268:DNA-Binding Proteins / Q000235:genetics*; D006655:Histone Deacetylases / Q000235:genetics / Q000378:metabolism; D006657:Histones / Q000235:genetics / Q000502:physiology; D008954:Models, Biological; D009687:Nuclear Proteins / Q000235:genetics*; D009707:Nucleosomes / Q000235:genetics / Q000378:metabolism; D012319:RNA Polymerase II / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*; D014158:Transcription, Genetic
C065455:CYC8 protein, S cerevisiae; D004268:DNA-Binding Proteins; D006657:Histones; D009687:Nuclear Proteins; D009707:Nucleosomes; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; C066502:TUP1 protein, S cerevisiae; D012319:RNA Polymerase II; D006655:Histone Deacetylases