Biochemistry of Cell Cycle Regulation

细胞周期调控的生物化学

• 批准号: 6625767
• 负责人: MARK J SOLOMON
• 金额: $ 36.79万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-30 至 2006-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6625767
• 关键词: Schizosaccharomyces pombe; Xenopus oocyte; biochemical evolution; biochemistry; cell cycle; cell cycle proteins; cell growth regulation; cell line; cyclin dependent kinase; enzyme activity; phosphorylation; polymerase chain reaction; protein kinase; protein structure function; protein tyrosine phosphatase; western blottings

DESCRIPTION (provided by applicant): Progression through the cell cycle is regulated by the sequential activation and inactivation of cyclin-dependent protein kinase (cdks). All of the cell cycle cdks, such as human Cdc2, Cdk2, and Cdk4, and yeast Cdc2Sp, require an activating phosphorylation on a site equivalent to Thr-160 in human Cdk2. This phosphorylation is carried out by CAK, the Cdk-Activating Kinase. In most species, CAK consists of a catalytic subunit, Cdk7, a regulatory subunit, cyclin H, and an assembly factor, MAT 1. All three of these proteins are also subunits of the general transcription factor TFIIH. In yeast, however, CAK consists of a single polypeptide, Cakip. The phosphorylation that is carried out by CAK is removed by Type 2C phosphatases (PP2Cs). These studies are aimed at furthering our understanding of activating phosphorylations of cdks, both in yeast and in vertebrates. The Specific Aims of this project are: 1) To use "analog-sensitive" (asi) and "analog-specific" (as2) forms of Cakip and CDK7 to study CAK functions and substrates in yeast and humans. 2)To characterize the regulation of PP2C activity by N-terminal myristoylation and to identify additional PP2C substrates in yeast. 3)To test the hypothesis that the differences in the CDK activation pathways of budding yeast and of most other species result from the closed vs. open mitoses in these organisms, respectively. 4)To investigate why CDKs have been designed to require activating phosphorylations and to determine the consequences of not dephosphorylating a mammalian CDK following cyclin degradation.

描述（由申请人提供）：细胞周期的进展是 受细胞周期蛋白依赖性细胞周期蛋白的连续激活和失活调节 蛋白激酶（cdks）。所有细胞周期cdks，例如人类Cdc2、Cdk2、 Cdk4 和酵母 Cdc2Sp 需要一个位点上的激活磷酸化 相当于人类 Cdk2 中的 Thr-160。该磷酸化是通过 CAK，Cdk 激活激酶。在大多数物种中，CAK 由催化 亚基 Cdk7、调节亚基细胞周期蛋白 H 和组装因子 MAT 1。 所有这三种蛋白质也是一般转录的亚基 因子 TFIIH。然而，在酵母中，CAK 由单一多肽 Cakip 组成。 由 CAK 进行的磷酸化被 Type 2C 去除 磷酸酶（PP2C）。这些研究旨在加深我们的理解 在酵母和脊椎动物中激活 cdks 的磷酸化。这 该项目的具体目标是： 1）使用“模拟敏感”（asi）和 Cakip 和 CDK7 的“模拟特异性”(as2) 形式，用于研究 CAK 功能和 酵母和人类的底物。 2）表征PP2C的调节 通过 N 端肉豆蔻酰化来检测活性并鉴定额外的 PP2C 酵母中的底物。 3）检验CDK差异的假设 芽殖酵母和大多数其他物种的激活途径是由 这些生物体中分别有闭合有丝分裂和开放有丝分裂。 4）调查原因 CDK 被设计为需要激活磷酸化并确定 细胞周期蛋白后不去磷酸化哺乳动物 CDK 的后果 降解。