Structure-function study of CDK complexes

细胞的生长和分裂在分子水平上受到包括细胞周期蛋白依赖性蛋白激酶（CDK）在内的一系列酶的严格控制。这些酶以有序的顺序打开和关闭，以确保细胞分裂在所需的时间开始和停止。虽然在序列上密切相关，但对CDK家族不同成员的生物学研究表明，每个成员都具有独特的特性。我们的工作，使用X射线晶体学技术，使我们能够看到这些分子在原子分辨率的结构，从而了解它们彼此之间的差异。我们工作的第一个目的是确定CDK家族的底物的序列模式。我们可以使用这些模式来识别人类基因组中编码的潜在底物。这些研究还将确定适合通过X射线晶体学分析的底物，这将提供对它们如何与CDK相互作用的理解。CDK活性受CDK与细胞周期蛋白和CKS蛋白家族成员结合的调节。我们工作的第二个目的是使用动力学，生物物理和结构的方法来提供解释细胞周期蛋白和CKS蛋白如何调节CDK活性。异常的CDK活性与癌症、神经系统疾病和类风湿性关节炎有关。近年来，了解导致疾病的特定缺陷导致了针对特定靶点的令人兴奋的新药（例如用于癌症治疗的药物Gleevec，Iressa和Herceptin）。许多CDK选择性抑制剂正在进行治疗癌症的临床试验。这些试剂都通过结合CDK活性位点来阻断CDK活性。阻断由CDK/细胞周期蛋白复合物产生的其他相互作用的化合物代表了CDK定向疗法的替代靶标。本项目中描述的工作，阐述了介导底物与CDK和CDK调节蛋白结合的相互作用，将有助于进一步开发此类化合物，也可能揭示抑制剂开发的其他靶点。

The growth and division of cells is strictly controlled at the molecular level by a series of enzymes that include the cyclin dependent protein kinases (CDKs). These enzymes are switched on and off in an orderly sequence to ensure that cell division starts and stops at the required time. Though closely related in sequence, biological studies of the different members of the CDK family have revealed that each has unique properties. Our work, using the technique of X-ray crystallography, allows us to see the structure of these molecules at atomic resolution and so to learn how they differ from each other. The first aim of our work is to identify the sequence patterns that characterise substrates of the CDK family. We can use these patterns to identify potential substrates encoded within the human genome. These studies will also identify substrates suitable for analysis by X-ray crystallography that will provide an understanding of how they interact with CDKs. CDK activity is regulated by CDK binding to members of the cyclin and CKS protein families. The second aim of our work is to use kinetic, biophysical and structural methods to provide explanations for how cyclins and CKS proteins regulate CDK activity. Aberrant CDK activity has been linked to cancer, neurological diseases, and rheumatoid arthritis. In recent years, understanding a particular defect that leads to disease has led to exciting new medicines directed towards a particular target (e.g. the drugs Gleevec, Iressa and Herceptin for cancer treatment). A number of CDK-selective inhibitors are in clinical trials for the treatment of cancer. These agents all act by binding to the CDK active site to block CDK activity. Compounds that block other interactions made by CDK/cyclin complexes represent an alternative target for CDK-directed therapies. The work described in this project, to elaborate the interactions that mediate the binding of substrates to CDKs and CDK-regulatory proteins, will aid the further development of such compounds and may also reveal additional targets for inhibitor development.