CDK-containing macromolecular assemblies

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（CDKs）在内的许多酶的严格控制。cdk1、2、4和6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。CDK家族的其他成员（cdk7,8和9）对转录的控制也很重要，转录是基因转录成信使RNA的过程，信使RNA反过来作为蛋白质合成的模板。转录调节确保了细胞生长和分化所需的蛋白质的及时表达。控制细胞周期进程或转录的错误可导致不受控制的细胞生长和增殖。虽然CDK家族成员在序列上密切相关，但生物学研究表明，每个成员都具有独特的特性。它们的活性可以通过与不同的调节蛋白家族结合或通过在特定氨基酸侧链上添加磷酸化或乙酰基残基对蛋白质序列进行酶修饰来调节。我们的工作，主要是使用x射线晶体学技术，使我们能够看到CDKs的结构和它们在原子分辨率下形成的复合物，从而了解它们彼此之间的区别。本提案的目的是建立在我们对CDK/细胞周期蛋白对的结构和功能特性的研究基础上，确定当它们位于多蛋白复合物中时，结构和生化特性是如何改变的。为此，我们建议使用异源表达系统鉴定和重建选定的含cdk复合物。我们将通过结构、生化和生物物理方法来描述这些复合物。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，对导致疾病的特定缺陷的理解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格列卫、易瑞沙和赫赛汀）。许多cdk选择性抑制剂正在临床试验中用于治疗癌症。这些药物都通过结合CDK活性位点来阻断CDK活性。阻断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定向治疗的另一种靶点。本项目所描述的工作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 number of enzymes that include the cyclin dependent protein kinases (CDKs). CDKs 1, 2, 4 and 6 are switched on and off in an orderly sequence, to ensure that cell division starts and stops at the required time. Other members of the CDK family (CDKs 7, 8 and 9) are also important for the control of transcription, the process by which genes are transcribed into messenger RNA that in turn serves as the template for protein synthesis. Regulation of transcription ensures the timely expression of proteins required for cell growth and differentiation. Errors in either the control of cell cycle progression or transcription can lead to uncontrolled cell growth and proliferation. Although CDK family members are closely related in sequence, biological studies have revealed that each has unique properties. Their activities can be regulated both by association with different families of regulatory proteins and by enzymatic modification of the protein sequence by addition of phosphoryl or acetyl residues to specific amino acid side chains. Our work, primarily using the technique of X-ray crystallography, allows us to see the structures of CDKs and the complexes they form at atomic resolution and so to learn how they differ from each other. The aim of this proposal is to build upon our research into the structural and functional properties of CDK/cyclin pairs, to establish how structural and biochemical properties are altered when they are located in multi-protein complexes. To this end we propose to identify and reconstitute selected CDK-containing complexes using heterologous expression systems. We will characterise these complexes by structural, biochemical, and biophysical methods. 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 will aid the further development of such compounds and may also reveal additional targets for inhibitor development.