Cell Cycle control by cyclin-dependent kinases

超出所提供的空间。细胞周期蛋白依赖性激酶（Cdks）驱动真核细胞周期的事件。cdks被认为是通过磷酸化细胞中大量的蛋白质底物来起作用的，但是这些底物中很少被鉴定。在拟议的研究中，一种新的生化策略将被用来进行大规模的搜索，在芽殖酵母和脊椎动物的Cdk底物。 我们的初步研究已导致芽殖酵母中约200个Cdkl底物的鉴定，并且在所提出的工作的第一个目标中，将详细分析这些底物的子集。其他的初步工作表明，相关的细胞周期蛋白亚基的身份有一个深刻的影响，在Cdkl磷酸化许多酵母底物的速度，和拟议的研究的第二个目的将是探索这种细胞周期蛋白特异性的分子基础及其在细胞中的生理功能。 方法也将被开发用于脊椎动物细胞中大量的Cdk底物的系统识别和表征。最后，将采用"化学遗传学"方法来构建小鼠和小鼠细胞系，其中Cdkl或Cdk2可以以高特异性被抑制，从而允许严格分析它们在正常细胞生物学和肿瘤中的功能。 这些研究有望为Cdks驱动细胞周期事件的基本机制提供广泛的新见解。这些见解是更好地理解染色体分离缺陷和其他细胞周期缺陷的重要一步，这些缺陷是癌细胞的特征。性能现场=

EXCEED THE SPACE PROVIDED. Cyclin-dependent kinases (Cdks) drive the events of the eukaryotic cell cycle. Cdks are thought to act by phosphorylating a large number of protein substrates in the cell, but few of these substrates have been identified. In the proposed studies, a novel biochemical strategy will be used to perform large scale searches for Cdk substrates in budding yeast and vertebrates. Our preliminary studies have led to the identification of about 200 Cdkl substrates in budding yeast, and in the first aim of the proposed work a subset of these substrates will be analyzed in detail. Other preliminary work has revealed that the identity of the associated cyclin subunit has a profound effect on the rate at which Cdkl phosphorylates many yeast substrates, and the second aim of the proposed studies will be to explore the molecular basis of this cyclin specificity and its physiological function in the cell. Methods will also be developed for the systematic identification and characterization of large numbers of Cdk substrates in vertebrate cells. Finally, a 'chemical genetic' approach will be employed to construct mice and mouse cell lines in which Cdkl or Cdk2 can be inhibited with high specificity, allowing rigorous analysis of their function in normal cell biology and in tumors. These studies promise to provide a wide range of new insights into the basic mechanisms by which Cdks drive cell-cycle events. Such insights are an important step toward a better understanding of the chromosome segregation defects and other cell-cycle defects that characterize the cancer cell. PERFORMANCE SITE ========================================Section End===========================================