Microtubule/Actin Interactions in Cell Motility

细胞运动中的微管/肌动蛋白相互作用

• 批准号: 7118202
• 负责人: Clare Michal Waterman
• 金额: $ 35.89万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7118202
• 关键词: Urodela; actins; cell migration; cell motility; chickens; crosslink; cytoskeletal proteins; fluorescence microscopy; green fluorescent proteins; guanine nucleotide binding protein; guanosinetriphosphatases; image processing; laboratory rabbit; microtubules; molecular /cellular imaging; protein protein interaction; proteomics; respiratory epithelium; small interfering RNA; tissue /cell culture

DESCRIPTION (provided by applicant): Microtubules (MTs) and filamentous actin (f-actin), are required for directed tissue cell motility. Spatial control of f-actin polymerization and actomyosin contraction is essential to generate a self perpetuating asymmetry of lamellipodial protrusion in the front and retraction in the rear to drive cell motility. MTs provide spatial and temporal orchestration of these f-actin-based events, however the molecular basis is poorly understood. MTs and f-actin exhibit two mechanistic categories of interactions in migrating cells. "Structural Interactions" in which f-actin and MTs are physically cross linked, and thus directly affect each other's organization and dynamics. "Regulatory Interactions" are those in which the activities of Rho-family small GTPase signaling cascades are spatiotemporally controlled by the assembly and disassembly of MTs, and at the same time, Rho GTPases regionally co-regulate the dynamics of MTs and f-actin. It is critical for our understanding of the mechanisms of polarized cell motility to discover the molecular linkages between the microtubules and actin cytoskeletons and the molecular mechanisms that regulate these linkages and the feedback between the dynamics of the actin and MT cytoskeletal arrays. Specific Aims:A.1. Test the hypothesis that specific classes of structural interactions between MTs and f-actin are required to mediate directed cell motility.A.2. Dissect the molecular mechanism of Rac1 GTPase-induced MT growth and test the hypothesis that Rac1-mediated promotion of microtubule growth is required for cell motility.A.3. Test the hypothesis that the adenomatous polyposis coli protein (ARC) mediates MT growth- activation of lamellipodial protrusion and Rac1 GTPase. A.4. Develop automated image analysis tools to quantitate the assembly, disassembly and movement of large populations of MTs in living cells. The experiments proposed in this grant will provide significant advances in our understanding of the basic mechanism of cell motility and provide important new technology that will aid in the advancement of other areas of biological science if they are achieved.

描述（由申请人提供）：定向组织细胞运动需要微管（MTS）和丝状肌动蛋白（F-肌动蛋白）。 F-肌动蛋白聚合和肌动蛋白收缩的空间控制对于产生前部层状突起的自永久不对称性和后部缩回以驱动细胞运动至关重要。 MT提供了这些基于F-肌动蛋白事件的空间和时间编排，但是分子基础知之甚少。 MT和F-肌动蛋白在迁移细胞中表现出两种机械类别。 F-肌动蛋白和MT物理交叉链接，从而直接影响彼此的组织和动态的“结构相互作用”。 “调节性相互作用”是Rho-family小GTPase信号传导级联的活性由MTS组装和拆卸的空间控制，同时Rho GTPases区域在区域内共同调节MTS和F-肌动蛋白的动力学。对于我们对极化细胞运动机制的理解至关重要的是，发现微管与肌动蛋白细胞骨架之间的分子链接以及调节这些链接的分子机制以及肌动蛋白和MT细胞骨骼骨骼阵列的动力学之间的反馈。具体目的：A.1。检验以下假设：MTS与F-肌动蛋白之间的特定结构相互作用需要介导定向细胞运动。A.2。解剖RAC1 GTPase诱导的MT生长的分子机制，并检验了Rac1介导的微管生长的促进是细胞运动所必需的。A.3。测试腺瘤性息肉病蛋白（ARC）介导MT生长激活层状叶片突出和Rac1 GTPase的假设。 A.4。开发自动图像分析工具，以量化活细胞中大量MT的组装，拆卸和运动。这笔赠款中提出的实验将在我们对细胞运动的基本机制的理解中提供重大进步，并提供重要的新技术，以帮助其他生物科学领域的进步。