BIOCHEMISTRY OF CELL CYCLE REGULATION

细胞周期调节的生物化学

基本信息

批准号：
6385753
负责人：
MARK J SOLOMON
金额：
$ 35.61万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
1992
资助国家：
美国
起止时间：
1992-09-30 至 2002-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6385753
关键词：
Schizosaccharomyces pombe Xenopus alternatives to animals in research cell cycle cell growth regulation chemical binding cyclin dependent kinase enzyme activity enzyme inhibitors enzyme structure fungal genetics molecular cloning phosphorylation protein structure function protein tyrosine phosphatase western blottings

项目摘要

DESCRIPTION: Progression through the cell cycle is regulated by the sequential activation and inactivation of a number of cyclin-dependent protein kinase (cdks). Many cdks, such as p34cdc2, and cdc4 require an activating phosphorylation on a site equivalent to Thr-161 in human p34cdc2. This phosphorylation is carried out by CAK, the Cdk-Activating Kinase. Solomon and others purified vertebrate CAK and found that it contained at least two proteins, a catalytic subunit termed p40MO15 (or cdk7), and a regulatory subunit, cyclin H. Both proteins are also subunits of the general transcriptio factor TFIIH. He recently purified CAK from the budding yeast, and found that it was composed of a single subunit (Cak1p) with unusual protein kinase motifs and only distant similarity to previously identified CAKs. Since the transcription function of p40MO15 is performed in yeast by Kin28p, the identification of Cak1p as the physiological yeast CAK suggested that there might be an additional vertebrate CAK, one more like Cak1p than p40MO15. These studies are aimed at furthering our understanding of CAK, both in yeast and in vertebrates. The Specific Aims of this project are: 1) To determine the range of Cak1p's substrates, how it is regulated, and its three-dimensional structure. 2) To characterize the end-product inhibition of Cak1p and to determine its physiological role. 3) To determine whether p40MO15 is a physiological CAK in vertebrates, to screen other fungi for evidence of a Cak1p-like CAK, to search for an additional vertebrate CAK, similar to yeast Cak1p, and to assess its functional importance. 4) To identify and study the phosphatase that counters Cak1p by dephosphorylating Thr-169 of Cdc28p.

描述：细胞周期的进展受以下因素调节一系列细胞周期蛋白依赖性的序列激活和失活蛋白激酶（cdks）。许多 cdks，例如 p34cdc2 和 cdc4 需要激活相当于人 p34cdc2 中 Thr-161 的位点的磷酸化。这种磷酸化是由 Cdk 激活激酶 CAK 进行的。 Solomon等人纯化了脊椎动物CAK，发现它含有至少两种蛋白质，一个称为 p40MO15（或 cdk7）的催化亚基，以及一个调节亚基，细胞周期蛋白 H。这两种蛋白也是通用蛋白的亚基转录因子TFIIH。他最近从芽殖酵母中纯化了 CAK，并发现它由一个具有不寻常的亚基（Cak1p）组成蛋白激酶基序，与之前发现的仅有遥远的相似性 CAK。由于 p40MO15 的转录功能是在酵母中通过 Kin28p，Cak1p鉴定为生理酵母CAK提示可能还存在一种额外的脊椎动物 CAK，它比 Cak1p 更像 Cak1p p40MO15。这些研究旨在加深我们对 CAK 的理解，在酵母和脊椎动物中。该项目的具体目标是： 1) 确定 Cak1p 底物的范围、其调节方式以及它的三维结构。 2) 表征最终产品抑制Cak1p并确定其生理作用。 3) 至确定p40MO15是否是脊椎动物中的生理性CAK，以筛选其他真菌寻找 Cak1p 样 CAK 的证据，以寻找额外的脊椎动物 CAK，类似于酵母 Cak1p，并评估其功能重要性。 4) 鉴定并研究对抗 Cak1p 的磷酸酶使 Cdc28p 的 Thr-169 去磷酸化。