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：该研究项目的重点是了解Cortactin是一种F-肌动蛋白结合蛋白，在细胞运动和肿瘤细胞侵袭中的作用。拟议的研究的长期目标集中在皮质素和相关蛋白在薄片中的作用，其功能与信号转导和运动性有关，以及Cortactin过表达如何影响细胞运动，粘附和肿瘤细胞的侵入性。该应用特异性地解决了cortactin在基于ARP2/3-F-肌肉蛋白的皮质细胞骨架组织中的功能，以及Cortactin如何用于调节正常和肿瘤细胞运动。 Cortactin是包括SRC在内的多种酪氨酸激酶的底物，在30％的头颈部鳞状细胞癌（HNSCCS）中表达过多。基于初步数据，假定皮质素通过一种涉及酪氨酸磷酸化的机制以及ARP2/3-F-肌动蛋白网络的激活和保护。 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.在AIM 1中，我们将解决Cortactin酪氨酸磷酸化是否会影响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Cortactin酪氨酸磷酸化会影响lamellipodia动力学，并确定Cortactin是否可以通过差异化ADFFIN来保护Cortactin，并确定Cortactin是否可以保护ARP2/3-F-肌动蛋白。 AIM 2将检查由RNAi衍生出的降低或消除Cortactin表达的细胞，以确定Cortactin如何影响皮质肌动蛋白细胞骨架，细胞迁移和粘附。 AIM 3将检查Cortactin的过表达如何通过确定过表达皮质素的HNSCC细胞系中的ARP2/3复合缔合和激活是否增强了HNSCC的侵入性特性，并确定细胞浸润和细胞外基质基质蛋白水解是否会因HNSCC中皮质素过表达而增加。所提出的目标的完成将更好地理解cortactin在细胞迁移和肿瘤细胞侵袭/转移中的功能。