Transcriptional regulation of a Ras nucleotide-exchange factor gene by extracellular signals in fission yeast

摘要: The ste6 gene of Schizosaccharomyces pombe encodes a putative GDP-GTP exchange factor for the ras1 product. Genetic analysis and genes has shown that they are required mating response to pheromones. In this study we show expression ste6-encoded mRNA is induced by nitrogen starvation, physiological signal triggers sexual differentiation. Exposure pheromones enhances induction upon starvation. Pheromone-induced requires not only function components pheromone-signalling pathway, but also function. Furthermore, mutants in which Ras1 protein activated have higher basal levels than wild-type cells. These observations indicate existence positive-feedback loop through stimulates its own activator. Since Ste6 likely promote guanine nucleotides on protein, our results suggest an important role regulation activity during process S. pombe.