Crosby J A, Konopka J B, Fields S
Program in Biochemistry and Molecular Biology, Department of Molecular and Cellular Biology, State University of New York at Stony Brook, 11794, USA.
Yeast. 2000 Nov;16(15):1365-75. doi: 10.1002/1097-0061(200011)16:15<1365::AID-YEA630>3.0.CO;2-S.
The transcriptional activator Ste12p is required for the expression of genes induced by mating pheromone in the yeast Saccharomyces cerevisiae. We identified mutations in the amino-terminal DNA-binding domain of Ste12p that lead to constitutively high-level transcription of pheromone-induced genes. The behaviour of these mutant proteins is consistent with an enhanced DNA-binding ability. Cells carrying these hyperactive proteins retain their sensitivity to pheromone treatment, and their phenotype is largely dependent on the presence of at least one of the MAP kinases (Fus3p or Kss1p) and the scaffold protein Ste5p. Deletion of either FUS3 or KSS1 leads to a marked increase in Ste12p activity, consistent with a negative regulatory role for Fus3p, similar to that described for Kss1p. The properties of the constitutive mutants support the idea that the pheromone response pathway plays a role in basal as well as pheromone-induced transcription.
转录激活因子Ste12p是酿酒酵母中交配信息素诱导基因表达所必需的。我们在Ste12p的氨基末端DNA结合结构域中鉴定出突变，这些突变导致信息素诱导基因的组成型高水平转录。这些突变蛋白的行为与增强的DNA结合能力一致。携带这些活性过高蛋白的细胞对信息素处理仍保持敏感性，并且它们的表型很大程度上取决于至少一种MAP激酶（Fus3p或Kss1p）和支架蛋白Ste5p的存在。删除FUS3或KSS1中的任何一个都会导致Ste12p活性显著增加，这与Fus3p的负调控作用一致，类似于对Kss1p的描述。组成型突变体的特性支持这样一种观点，即信息素反应途径在基础转录以及信息素诱导的转录中都发挥作用。
