Ssn6-Tup1 Is a General Repressor of Transcription in Yeast

Cell. 1992 Feb 21;68(4):709-19. doi: 10.1016/0092-8674(92)90146-4.

Abstract

The homeodomain protein alpha 2 and the SRF-like protein Mcm1 are required to establish cell type in the yeast Saccharomyces cerevisiae. Together, these regulatory proteins recognize a specific DNA operator, marking a set of genes for transcriptional repression. In this paper, we show that occupancy of the operator by alpha 2-Mcm1 is not sufficient to bring about repression. Rather, repression is effected only when Ssn6 (a TPR protein) and Tup1 (a beta-transducin repeat protein) are also present in the cell. We show that Ssn6 represses transcription when brought to a promoter by a bacterial DNA-binding domain and that Tup1 is required for this repression. Based on these and other results, we propose that Ssn6-Tup1 is a general repressor of transcription in yeast, recruited to target promoters by a variety of sequence-specific DNA-binding proteins.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Immunoblotting
  • Models, Genetic
  • Plasmids
  • Repressor Proteins / genetics*
  • Saccharomyces cerevisiae / genetics*
  • Transcription, Genetic

Substances

  • Repressor Proteins