Association of the cell cycle transcription factor Mbp1 with the Skn7 response regulator in budding yeast.
We previously isolated the SKN7 gene in a screen designed to isolate new components of the G1-S cell cycle transcription machinery in budding yeast. We have now found that Skn7 associates with Mbp1, the DNA-binding component of the G1-S transcription factor DSC1/MBF. SKN7 and MBP1 show several genetic interactions. Skn7 overexpression is lethal and is suppressed by a mutation in MBP1. Similarly, high overexpression of Mbp1 is lethal and can be suppressed by skn7 mutations. SKN7 is also required for MBP1 function in a mutant compromised for G1-specific transcription. Gel-retardation assays indicate that Skn7 is not an integral part of MBF. However, a physical interaction between Skn7 and Mbp1 was detected using two-hybrid assays and GST pulldowns. Thus, Skn7 and Mbp1 seem to form a transcription factor independent of MBF. Genetic data suggest that this new transcription factor could be involved in the bud-emergence process.
Bouquin
N
N
Division of Yeast Genetics, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, United Kingdom.
Johnson
A L
AL
Morgan
B A
BA
Johnston
L H
LH
D002453:Cell Cycle / Q000235:genetics; D002470:Cell Survival / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics*; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D009154:Mutation; D010957:Plasmids; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014170:Transformation, Genetic
D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C083209:MBP1 protein, S cerevisiae; C083962:SKN7 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors