REGULATION OF MICROTUBULES BY RHO GTPASES

RHO GTP酶对微管的调节

基本信息

批准号：
8204449
负责人：
Gregg G Gundersen
金额：
$ 43.08万
依托单位：
COLUMBIA UNIVERSITY HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
2001
资助国家：
美国
起止时间：
2001-04-01 至 2013-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8204449
关键词：
Abnormal Cell Actins Address Adenomatous Polyposis Coli Protein Adhesions Behavior Binding Biochemical Biological Biological Assay Biological Models COX7A2L Protein Cell Nucleus Cell Polarity Cell physiology Cells Centrosome Characteristics Cues Cytokinesis Cytoskeleton DNA Sequence Rearrangement Development Disease Elements Eukaryotic Cell Event Family Fibroblasts Generations Genetic Goals Grant Growth Factor Guanosine Triphosphate Phosphohydrolases Image Immune response In Vitro Inflammation Kinesin Knowledge Lead Length Life Lysophospholipids Mediating Microtubule Stabilization Microtubules Molecular Monomeric GTP-Binding Proteins Motor Mus Neoplasm Metastasis Orthologous Gene Pathway interactions Phenotype Polymers Positioning Attribute Process Proteins Regulation Role Serum Signal Pathway Signal Transduction Site Specificity System Testing Work Wound Healing Xenopus cell associated matrix cell cortex cell motility cellular transduction combat in vivo lysophosphatidic acid migration monolayer mutant neuronal cell body new therapeutic target novel polymerization public health relevance research study response rho rho GTP-Binding Proteins single molecule wound

项目摘要

DESCRIPTION (provided by applicant): The overall goal of this project is to understand how small GTPases of the Rho family regulate the stability and organization of microtubules (MTs) during polarization of cells for migration. The dynamics of MTs allows them to response to external signals during cell polarization and Rho GTPase signaling pathways are known to transduce these signals to MTs to bring about changes in their stability and organization. Cell migration into an in vitro wound is a model system for studying the signals regulating MT as the contribution of soluble, matrix and cell-associated factors can be dissected. The serum factor lysophosphatidic acid (LPA) stimulates separate Rho and Cdc42 signaling pathways that regulate two characteristic rearrangements of MTs in wound edge migrating fibroblasts: formation of a subset of unusually stable MTs and reorientation of the centrosome. In previous grant periods, we identified many of the factors in the pathways that are activated by these GTPases and have found that the pathways alter the dynamics of MTs near the cell cortex, a process termed MT capture. Yet, it is unknown how the proteins activated by these signaling pathways mediate MT capture or how the captured MTs influence cellular behavior. The current aims focus on the mechanism by which MT capture leads to long-lived MTs and the role of these stabilized MTs in motile processes in migrating cells. In addition to their well-characterized roles in regulating the actin cytoskeleton, formins have emerged as important regulators of MTs. We will explore the role of the formin mDia1 in generating stabilized MTs by defining its sites of interaction with MTs, determining its intrinsic ability to regulate MT dynamics, examining how interacting proteins, such as the MT +TIPs, alter its activity toward MTs and testing whether its interaction with MTs alters its actin polymerizing activity. We will explore the relationship between mDia1 and a kinesin motor protein that we have identified as a novel regulator of MT stabilization in cells. Approaches will be developed to specifically interfere with the generation of stable MTs in migrating cells so that their contribution to motile processes in cells can be determined. Understanding how Rho GTPase signaling pathways act to regulate MTs will provide new information about the fundamental ways cells transduce signals to cytoskeletal systems during cell migration, a process of importance for development, wound healing and metastasis. PUBLIC HEALTH RELEVANCE: Microtubules are dynamic cytoskeletal elements that contribute to cellular responses to external cues, such as growth factor stimulation. In migrating cells, microtubules contribute to the polarization of cellular activities that allow the cell to migrate in a directional fashion but the molecular mechanisms involved are unclear. Understanding the molecular mechanism controlling microtubules in migrating cells will contribute to fundamental knowledge of how cells migrate during development, wound healing and immune response and may lead to the identification of novel therapeutic targets for combating diseases involving abnormal cell migration, such as cancer metastasis and inflammation.

描述（由申请人提供）：该项目的总体目标是了解RHO家族的小GTPase如何调节细胞偏振迁移的偏振过程中微管（MTS）的稳定性和组织。 MTS的动力学使他们能够在细胞极化期间对外部信号响应，而Rho GTPase信号通路可以将这些信号转换为MT，从而带来其稳定性和组织的变化。细胞迁移到体外伤口是一种模型系统，用于研究调节MT的信号，因为可以阐述可溶性，基质和细胞相关因子的贡献。血清因子溶物磷脂酸（LPA）刺激单独的RHO和CDC42信号通路，这些途径调节了迁移成纤维细胞的MTS的两个特征重排：形成了异常稳定的MTS的子集和中心体的重新定向。在以前的赠款期间，我们确定了这些GTPases激活的途径中的许多因素，并发现途径改变了细胞皮质附近MT的动力学，这一过程称为MT捕获。然而，未知这些信号通路激活的蛋白质如何介导MT捕获或捕获的MT如何影响细胞行为。当前的目的集中在MT捕获导致长期寿命的MT以及这些稳定MT在迁移细胞中运动过程中的作用的机制。除了它们在调节肌动蛋白细胞骨架中的特征性作用外，甲素还成为MT的重要调节剂。我们将通过定义其与MTS的相互作用的位点来探讨formin MDIA1在生成稳定的MT中的作用，确定其固有的调节MT动力学的能力，研究MT +TIPS等相互作用的蛋白质，例如如何改变其对MTS的活性并测试其与MTS Alters Alters Alters Alters Altters Altters Actin Polymerization polymerization polymerizatization。我们将探索MDIA1与动力蛋白运动蛋白之间的关系，我们已将其确定为细胞中MT稳定的新调节剂。将开发方法以特异性干扰迁移细胞中稳定的MT的产生，以便可以确定它们对细胞运动过程的贡献。了解Rho GTPase信号通路如何调节MTS将提供有关细胞信号在细胞迁移过程中转导信号向细胞骨架系统的基本信息的新信息，这是对发育，伤口愈合和转移的重要性过程。公共卫生相关性：微管是动态细胞骨架元素，有助于细胞对外部线索的反应，例如生长因子刺激。在迁移的细胞中，微管有助于细胞活性的极化，这些细胞活性使细胞以方向性的方式迁移，但涉及的分子机制尚不清楚。了解控制细胞中微管的分子机制将有助于对细胞在发育，伤口愈合和免疫反应过程中如何迁移的基本知识，并可能导致鉴定出新的治疗靶标，以打击涉及异常细胞迁移的疾病，例如癌症转移和炎症。