The Biochemical Basis for the Mechanics of Cytokinesis

细胞分裂机制的生化基础

基本信息

批准号：
8269834
负责人：
DOUGLAS N ROBINSON
金额：
$ 32.95万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2003
资助国家：
美国
起止时间：
2003-08-01 至 2013-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8269834
关键词：
Actins Affect Aneuploidy Antineoplastic Agents Behavior Biochemical Cell Adhesion Cell Cycle Cell Shape Cell division Cell physiology Cells Computer Architectures Crosslinker Cytokinesis Cytoskeletal Modeling Data Daughter Dependency Disease Dissection Drosophila polo protein Drug Delivery Systems Event Evolution Failure Genes Genetic Goals Grant Human Image Lead Life Link Malignant Neoplasms Measures Mechanical Stress Mechanics Mediating Microtubules Modeling Molecular Mothers Myosin Type II Nocodazole Normal Cell Pathway interactions Plasmids Process Property Proteins RNA-Binding Proteins Race Regulatory Pathway Shapes Signal Transduction Source Specificity Stress Structure System Testing Tetraploidy Tumor Suppressor Genes Work aurora kinase base cancer cell cancer therapy cell growth chemical genetics clinical application crosslink daughter cell gene function in vivo inhibitor/antagonist inner centromere protein interest loss of function mutant novel particle physical property reconstitution response small molecule tumor

项目摘要

Project Summary Cytokinesis, the separation of a mother cell into two daughters, is an essential life process. Cytokinesis failure leads to tetraploidy then aneuploidy, an early event in tumor formation. We have been striving to understand how cells use proteins to generate the relevant cellular physical properties that drive cytokinesis contractility. We are also interested in developing small molecule inhibitors to aid in gene function identification and pathway dissection, but with the ultimate goal that some of these small molecule inhibitors will have clinical applications. In this proposal, we will build on the analytical framework that we initiated in the first cycle of the grant, but we will also expand our effort in several ways. In Aim 1, we will measure the lifetimes of myosin-II and various actin crosslinkers in different mutant backgrounds where the mechanics are known in order to assess the consequences of mechanical strain on crosslinker lifetimes. We will test our understanding of the molecular control of cytokinesis mechanics and dynamics by measuring cortical mechanics of dividing mutant strains where we have specific predictions of the mechanics. We will also begin studying lower hierarchical levels of cytoskeletal function by reconstituting crosslinked actin networks, applying mechanical strain to them, and studying the behavior of the crosslinkers and the network. We will use either FRAP or single particle analysis to assess the strain dependency of crosslinker lifetimes; we have several predictions based on our in vivo studies. In Aim 2, we will draw upon our observations that RacE is responsible for generating resistive stresses during cytokinesis and for restricting the mechanosensory system that we discovered to cytokinesis. In this Aim, we will identify RacE effectors to flesh out this pathway. We will study 14-3-3, which was identified as a suppressor of nocodazole. Genetic interactions between RacE and 14-3-3 further point towards a pathway in which microtubules regulate RacE and/or 14-3-3, which in turn regulate global actin crosslinkers to control the dynamics and mechanics of cytokinesis contractility. In Aim 3, we will expand our molecular inquiry by identifying the affected genes in the REMI mutants we have already recovered.

项目摘要细胞因子（将母细胞分为两个女儿）是一个必不可少的生活过程。细胞因子衰竭导致四倍体，然后导致非整倍性，这是肿瘤形成的早期事件。我们一直在努力理解细胞如何使用蛋白质生成驱动细胞因子收缩力的相关细胞物理特性。我们还有兴趣开发小分子抑制剂以帮助基因功能鉴定和途径解剖，但最终的目标是这些小分子抑制剂中的某些将具有临床申请。在此提案中，我们将建立在我们在第一个周期中启动的分析框架上格兰特，但我们还将以多种方式扩大我们的努力。在AIM 1中，我们将测量肌球蛋白-II的寿命以及在不同突变体背景下的各种肌动蛋白交联，以便为了评估机械应变对交联寿命的后果。我们将测试我们对通过测量分裂突变体的皮质力学对细胞因子力学和动力学的分子控制我们对机械师有特定预测的菌株。我们还将开始研究较低的层次结构通过重构交联的肌动蛋白网络，对其应用机械应变，将细胞骨架功能的水平并研究交联链和网络的行为。我们将使用FRAP或单个粒子分析以评估交联寿命的应变依赖性；我们有几个基于我们的预测体内研究。在AIM 2中，我们将借鉴我们的观察，即种族负责产生抵抗力细胞因子过程中的应力和限制了我们发现的细胞因子的机械增强系统。在此目标中，我们将确定种族效应者以充实这一途径。我们将研究14-3-3，已确定作为Nocodazole的抑制剂。种族与14-3-3之间的遗传相互作用进一步指向微管调节种族和/或14-3-3的途径，这反过控制细胞因子收缩力的动力学和力学。在AIM 3中，我们将扩展分子查询通过识别REMI突变体中的受影响基因，我们已经恢复了。