Cortactin in Cell Motility and Invasion

Cortactin 在细胞运动和侵袭中的作用

• 批准号: 6684810
• 负责人: Scott A Weed
• 金额: $ 25.57万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-10 至 2008-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6684810
• 关键词: actin binding protein; actins; cell adhesion; cell line; cell migration; cell motility; cytoskeleton; electron microscopy; extracellular matrix; immunofluorescence technique; metastasis; molecular assembly /self assembly; neoplastic cell; phosphorylation; protein structure function; proteolysis; squamous cell carcinoma; tyrosine; western blottings

DESCRIPTION: The focus of this research project is to understand how cortactin, an F-actin-binding protein, functions in cell motility and tumor cell invasion. The long-term goal of the proposed research centers on the role of cortactin and associated proteins in lamellipodia function as it pertains to signal transduction and motility, and how cortactin overexpression influences cell motility, adhesion and tumor cell invasiveness. This application specifically addresses the function of cortactin in the organization of the Arp2/3-F-actin based cortical cytoskeleton and how cortactin serves to regulate normal and tumor cell movement. Cortactin is a substrate for multiple tyrosine kinases, including Src, and is over expressed in 30% of head and neck squamous cell carcinomas (HNSCCs). Based on preliminary data, it is posited that cortactin dynamically regulates the cortical actin cytoskeleton by a mechanism that involves tyrosine phosphorylation along with activation and protection of Arp2/3-F-actin networks. The studies described here will use biochemical and cell biological analysis of fibroblast and HNSCC cell lines to explore the hypothesis that cortactin functions to regulate and stabilize cortical Arp2/3-F-actin networks during cell migration, and that enhanced dynamic regulation of Arp2/3-F-actin networks resultant from cortactin overexpression leads to increased invasion of HNSCC. In Aim 1, we will address if cortactin tyrosine phosphorylation affects Arp2/3 actin nucleation activity and its association with Arp2/3-F-actin networks, if cortactin tyrosine phosphorylation influences lamellipodia dynamics, and determine if cortactin protects Arp2/3-F-actin networks from disassembly by ADF/cofilin proteins. Aim 2 will examine cells with reduced or eliminated cortactin expression derived by RNAi to determine how cortactin impacts the cortical actin cytoskeleton, cell migration and adhesion. Aim 3 will examine how cortactin overexpression affects the invasive properties of HNSCC by determining if Arp2/3 complex association and activation are enhanced in HNSCC cell lines overexpressing cortactin, and to determine if cell invasion and extracellular matrix proteolysis is increased as a result of cortactin overexpression in HNSCC. Completion of the proposed Aims will provide a better understanding of how cortactin functions in cell migration and tumor cell invasion/metastasis.

描述：本研究项目的重点是了解一种f -肌动蛋白结合蛋白，如何在细胞运动和肿瘤细胞侵袭中起作用。本研究的长期目标是研究相关蛋白在板足功能中的作用，因为它与信号转导和运动有关，以及过表达相关蛋白如何影响细胞运动、粘附和肿瘤细胞侵袭性。本应用程序专门解决了在arp2 /3- f -肌动蛋白为基础的皮质细胞骨架组织中的联系功能，以及联系如何调节正常和肿瘤细胞的运动。皮质蛋白是多种酪氨酸激酶（包括Src）的底物，在30%的头颈部鳞状细胞癌（HNSCCs）中过表达。根据初步数据，我们假设皮质蛋白通过酪氨酸磷酸化以及arp2 /3- f -肌动蛋白网络的激活和保护机制动态调节皮质肌动蛋白细胞骨架。本文描述的研究将使用成纤维细胞和HNSCC细胞系的生化和细胞生物学分析来探索在细胞迁移过程中，接触蛋白调节和稳定皮层arp2 /3- f -肌动蛋白网络的功能，以及接触蛋白过表达导致的arp2 /3- f -肌动蛋白网络的动态调节增强导致HNSCC侵袭增加的假设。在Aim 1中，我们将探讨接触酪氨酸磷酸化是否影响Arp2/3肌动蛋白成核活性及其与Arp2/3- f -肌动蛋白网络的关联，如果接触酪氨酸磷酸化影响板足动力学，并确定接触是否保护Arp2/3- f -肌动蛋白网络免受ADF/cofilin蛋白的破坏。目的2将检测RNAi诱导的皮质蛋白表达减少或消除的细胞，以确定皮质蛋白如何影响皮质肌动蛋白细胞骨架、细胞迁移和粘附。目的3将通过确定Arp2/3复合物的关联和激活是否在过表达HNSCC的HNSCC细胞系中增强，并确定细胞侵袭和细胞外基质蛋白水解是否因HNSCC中的过表达而增加，来研究接触蛋白过表达如何影响HNSCC的侵袭特性。该研究的完成将有助于更好地理解细胞接触在细胞迁移和肿瘤细胞侵袭/转移中的作用。