A yeast transcription factor bypassing the requirement for SBF and DSC1/MBF in budding yeast has homology to bacterial signal transduction proteins

EMBO J. 1995 Nov 15;14(22):5679-89.


The transcription factors SBF and DSC1/MBF bind SCB and MCB promoter elements, respectively, and are essential for the cell cycle progression of Saccharomyces cerevisiae through the control of G1 cyclin gene expression. We isolated a gene (BRY1; Bacterial Response regulator in Yeast) able to activate either MCB or SCB promoter elements on a reporter plasmid which, when overexpressed, can bypass the normally essential requirement for SBF and DSC1/MBF by the stimulation of CLN1 and CLN2 expression. In the case of CLN2 at least, this expression depends upon the MCB and SCB promoter elements. In wild-type yeast, the disruption of BRY1 has no apparent phenotype, but under conditions where the activities of SBF and DSC1/MBF are reduced, BRY1 becomes essential. Our data imply the existence of a third pathway affecting cyclin expression. BRY1 is the same gene as SKN7 which has significant sequence homology to the receiver domains found in response regulator proteins from the bacterial two-component signal transduction pathways. SKN7 is thought to affect cell wall structure, and when highly overexpressed we find that BRY1/SKN7 is lethal perhaps because of perturbations in cell wall biosynthesis. The lethality is partially rescued by genes from the protein kinase C pathway, but genetic data imply that BRY1/SKN7 and protein kinase C are not in the same pathway. Our results suggest that Bry1/Skn7 can influence the expression of MCB- and SCB-driven gene expression in budding yeast, perhaps including genes involved in cell wall metabolism, via a two-component signal transduction pathway which activates Bry1/Skn7 in response to an unidentified signal.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cyclins / genetics
  • Cyclins / metabolism
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • G1 Phase
  • Gene Expression Regulation, Fungal*
  • Genes, Fungal
  • Heat Shock Transcription Factors
  • Promoter Regions, Genetic
  • Protein Kinase C / metabolism
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins*
  • Signal Transduction
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*


  • CLN1 protein, S cerevisiae
  • CLN2 protein, S cerevisiae
  • Cyclins
  • DNA-Binding Proteins
  • Fungal Proteins
  • Heat Shock Transcription Factors
  • SBF protein, S cerevisiae
  • SKN7 protein, S cerevisiae
  • SWI4 protein, S cerevisiae
  • SWI6 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors
  • Protein Kinase C