The Elm1 kinase functions in a mitotic signaling network in budding yeast

作     者：Sreenivasan, A Kellogg, D 

作者机构：Univ Calif Santa Cruz Dept Biol Sinsheimer Labs Santa Cruz CA 95064 USA 

出 版 物：《MOLECULAR AND CELLULAR BIOLOGY》 (分子生物学与细胞生物学)

年 卷 期：1999年第19卷第12期

页      面：7983-7994页

核心收录：

学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 07[理学] 

基　　金：NIGMS NIH HHS [GM53959  R01 GM053959] Funding Source: Medline 

主　　题：CDC28蛋白激酶 S酿酒酵母/代谢 细胞周期蛋白质类 细胞周期蛋白B/代谢 细胞周期蛋白质依赖激酶类/遗传学 细胞周期蛋白质依赖激酶类/代谢 细胞周期蛋白质依赖激酶类/生理学 酶激活 真菌蛋白质类/遗传学 真菌蛋白质类/代谢 真菌蛋白质类/生理学 基因 真菌 有丝分裂 诱变 磷酰化 蛋白质丝氨酸苏氨酸激酶/遗传学 蛋白质丝氨酸苏氨酸激酶/代谢 蛋白质丝氨酸苏氨酸激酶/生理学 蛋白酪氨酸激酶类/遗传学 蛋白酪氨酸激酶类/代谢 酿酒酵母菌/酶学 酿酒酵母菌/生长和发育 酿酒酵母蛋白质类 信号传导 动物 兔 

摘      要：In budding yeast, the Clb2 mitotic cyclin initiates a signaling network that negatively regulates polar bud growth during mitosis. This signaling network appears to require the function of a Clb2-binding protein called Nap1, the Cdc42 GTPase, and two protein kinases called Gin4 and Cla4. In this study, we demonstrate that the Elm1 kinase also plays a role in the control of bud growth during mitosis. Cells carrying a deletion of the ELM1 gene undergo a prolonged mitotic delay, fail to negatively regulate polar bud growth during mitosis, and show defects in septin organization. In addition, Elm1 is required in vivo for the proper regulation of both the Cla4 and Gin4 kinases and interacts genetically with Cla4, Gin4, and the mitotic cyclins. Previous studies have suggested that Elm1 may function to negatively regulate the Swe1 kinase. To further understand the functional relationship between Elm1 and Swe1, we have characterized the phenotype of Delta elm1 Delta swe1 cells. We found that Delta elm1 Delta swe1 cells are inviable at 37 degrees C and that a large proportion of Delta elm1 Delta swe1 cells grown at 30 degrees C contain multiple nuclei, suggesting severe defects in cytokinesis. In addition, we found that Elm1 is required for the normal hyperphosphorylation of Swe1 during mitosis. We propose a model in which the Elm1 kinase functions in a mitotic signaling network that controls events required for normal bud growth and cytokinesis, while the Swe1 kinase functions in a checkpoint pathway that delays nuclear division in response to defects in these events.