Cell Adhesion and the Regulation of Rho GTPases

细胞粘附和 Rho GTP 酶的调节

• 批准号: 7999960
• 负责人: Keith Burridge
• 金额: $ 11.84万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-12-31 至 2010-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7999960
• 关键词: Adherens Junction; Adhesions; Affect; Binding; Biosensor; C-terminal; Cadherin Domain; Cadherins; Cell Adhesion; Cell membrane; Cell-Cell Adhesion; Cells; Consensus Sequence; Coupled; Cytoskeleton; Data; Dominant-Negative Mutation; Environment; Extracellular Matrix; Extracellular Matrix Proteins; Family; Family member; Fibronectins; Fluorescence Resonance Energy Transfer; Focal Adhesions; Goals; Grant; Guanine; Guanine Nucleotide Exchange Factors; Guanosine Triphosphate Phosphohydrolases; Integrin Signaling Pathway; Integrins; Intercellular Junctions; Isometric Exercise; Life; Maps; Mass Spectrum Analysis; Measures; Mediating; Molecular Weight; Nucleotides; Null Lymphocytes; Organism; PDZ protein; Phosphorylation; Phosphotransferases; Process; Protein Tyrosine Kinase; Proteins; Proteoglycan; Recruitment Activity; Regulation; Relative (related person); Research Personnel; Signal Pathway; Signal Transduction; Site; Small Interfering RNA; Surface; System; Testing; Tight Junctions; Work; cell behavior; cellular imaging; density; flexibility; inhibitor/antagonist; member; mutant; physical state; research study; response; rho; rho GTP-Binding Proteins; scaffold; syndecan-4

Adhesion of cells to other cells and to the extracellularmatrix is a fundamental characteristicof all multicellular organisms. Adhesions providenot onlystructurallinksbetween the intracellularcytoskeletonand theextracellular environment, but also provide sites of signal transductionthat affect many aspects of cell behavior. This grant is aimed at understandinghow signals from cell-matrix and cell-cell adhesions regulate members of the Rho family of GTPases, which are themselves key regulators of the cytoskeleton and many intracellular processes. The goal of the first aim is to determine how adhesion to the extracellular matrix protein fibronectin stimulates RhoA activity. The respectiveroles of integrins and syndecan-4 will be investigated. We will explore the contribution of specific integrin type, density of expression and clustering on RhoA activation. Wewill test thehypothesis that some of syndecan-4's effects are mediated through activation of Rapl, another low molecular weight GTPase. Strategies for identifying and isolating guanine nucleotideexchange factors (GEFs) involved in RhoA activation will be used. We will explore signaling pathwaysthat regulate these GEFs. Cells can sense the physical state of the surface to which they adhere and we will test the hypothesis that isometric tension can stimulate RhoA activity. RhoA activity will be measuredusing biosensors expressed in singlecells and live cell imaging. We will determine whetherthe applicationof tension to singlecells locally activatesRhoA. The second aim is directedin part toward identifying the Racl GEFs that are activated in response to cadherin engagement. Inpreliminary work, we have discovered that many Rho family GEFs bind to PDZ domains. Proteins with PDZ domains are typically enriched in cell-cell junctions. We will determine whether the binding of GEFs to PDZ domains serves to recruit them to cell junctions and whether this interaction regulates their activity.

细胞对其他细胞和细胞外肿块的粘附是所有多细胞的基本特征 有机体。粘连providEnot仅在细胞内环骨骼和细胞上的细胞内构造 环境，但还提供信号转导的位点会影响细胞行为的许多方面。这笔赠款是 旨在了解细胞矩阵和细胞细胞粘连的信号调节Rho家族的成员 GTPases本身是细胞骨架和许多细胞内过程的关键调节剂。目标 第一个目的是确定对细胞外基质蛋白纤连蛋白的粘附如何刺激RhoA 活动。整联蛋白和Syndecan-4的尊重将进行研究。我们将探索贡献 特定整合素类型，在RhoA激活上的表达密度和聚类。 We Will测试了thepothesis Syndecan-4的某些效应是通过RAPL激活（另一种低分子量GTPase的激活）介导的。 识别和隔离参与RhoA激活的鸟嘌呤核苷酸换因子（GEF）的策略 将使用。我们将探索信号通路，该路径调节这些GEF。细胞可以感觉到身体状态 它们粘附的表面，我们将测试等距张力可以刺激RhoA的假设 活动。 RhoA活性将通过在单细胞和活细胞成像中表达的生物传感器进行测量。我们将 确定在局部激活张力的张力是否局部激活。第二个目标是指导 旨在确定响应钙粘蛋白参与的RACL GEF。非原则 工作，我们发现许多Rho家族GEF与PDZ域结合。具有PDZ结构域的蛋白质是 通常富含细胞 - 细胞连接。我们将确定GEF与PDZ域的结合是否服务 将它们招募到细胞连接处，以及这种相互作用是否调节其活性。