CELL CYCLE ARREST AND SIGNAL TRANSDUCTION IN YEAST

酵母交配途径为负增长提供了一个极好的范例 高等真核生物的控制和分化。 建议的目标 研究的目的是确定进化上保守的蛋白激酶，FUS 3， 发挥调节细胞周期和信号传导的关键功能 在交配和营养生长期间的转导。 提出了一 遗传学和生物化学方法相结合，努力 确定：A）FUS 3如何同时阻止有丝分裂细胞周期 通过抑制G1-细胞周期蛋白并激活受体/G蛋白- B）功能性的基础 FUS 3和KSS 1之间的冗余，一种同源推定的蛋白激酶 这也促进了信号转导。 为了实现这些目标， 该提案的具体目标是：1）诱变FUS 3以鉴定 蛋白质结构域，指定其多种功能，并使突变体， 后续目标。 2)使用FUS 3免疫复合物激酶测定来检测 生理相关蛋白质是否被FUS 3磷酸化 体外或体内与FUS 3相关，并检查FUS 3是如何 在体外和体内调节。 3)为了鉴定蛋白质， 与FUS 3相互作用或通过遗传筛选是其功能同源物。

The yeast mating pathway provides an excellent paradigm for negative growth control and differentiation in higher eukaryotes. The goal of the proposed research is to define how an evolutionarily conserved protein kinase, FUS3, exerts critical functions which regulate the cell cycle and signal transduction during mating and vegetative growth. It is proposed that a combination of genetic and biochemical approaches be taken in an effort to determine: A) How FUS3 simultaneously arrests the mitotic cell cycle through inhibition of a G1-cyclins and activates a receptor/G protein- coupled signal transduction pathway; B) The basis of the functional redundancy between FUS3 and KSS1, a homologous putative protein kinase which also promotes signal transduction. To accomplish these goals, the specific aims of the proposal are: 1) To mutagenize FUS3 to identify the protein domains that specify its multiple functions and to make mutants for subsequent aims. 2) To use a FUS3 immune complex kinase assay to test whether physiologically relevant proteins are either phosphorylated by FUS3 in vitro or associated with FUS3 in vivo, and to examine how FUS3 is regulated in vitro and in vivo. 3) To identify proteins which either interact with FUS3 or are its functional homologues by genetic screens.