FUNCTION OF P130 CAS IN CELL SURVIVAL

P130 CAS 在细胞存活中的功能

• 批准号: 6182024
• 负责人: QIANG YU
• 金额: $ 25.61万
• 依托单位: BOSTON UNIVERSITY MEDICAL CAMPUS
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2003-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6182024
• 关键词: apoptosis; biological signal transduction; cell adhesion; cell cell interaction; cell growth regulation; cell transformation; chimeric proteins; extracellular matrix proteins; growth factor; immunoprecipitation; phosphoproteins; phosphorylation; polymerase chain reaction; protein structure function; protein tyrosine phosphatase; site directed mutagenesis; tissue /cell culture; transfection; western blottings; yeast two hybrid system

The goal of the proposed research plan is to investigate an unexplored and important function of p130Cas in cellular physiology, i.e., its role in regulating cell death and survival. p130Cas, originally identified as a major tyrosine-phosphorylated protein in v-Crk or v-Src transformed cells, is a multifunctional cell signal assembly protein. It contains multiple structure motifs and interact with a number of signaling molecules, such as Crk, Src, and FAK. Consistent with its structural characteristics, p130Cas has been found to be functionally involved in cell transformation, adhesion, migration and actin organization. It is essential for normal animal development. Mutant mice lacking p130Cas die in utero showing marked systemic congestion and growth retardation. Function of p130Cas in cell death/survival regulation, however, has not been studied. During the course of our study on regulation of protein tyrosine phosphorylation and cell growth, we found p130Cas to be a key player in tyrosine phosphatase LAR-induced apoptosis. LAR dephosphorylates and destabilizes the p130Cas protein. The down regulation of p130Cas by LAR leads to activation of a caspase pathway and induces apoptosis. Restoring p130Cas protein level alleviates the LAR-induced apoptosis. These data suggest a new function of p130Cas in regulating cell death/survival and a new mechanism by which the p130Cas protein is regulated. The present proposal is designed to investigate the function and mechanism of p130Cas in regulating cell death/survival. We will use a combination of biochemical, molecular, and cell biological techniques to identify specific signaling molecules and signal transduction pathways, through which p130Cas transduces cell death/survival signals. We will investigate the physiological relevance of p130Cas-mediated cell death by examining the regulation and function of p130Cas during anoikis, a form of cell death caused by detachment of epithelial and endothelial cells from their substratum, and in growth factor deprivation induced cell death, in both of which protein tyrosine phosphorylation/dephosphorylation play a critical role. Finally, the new mechanism regulating p130Cas protein level will also be investigated. The proposed study will increase our knowledge on function and mechanism of p130Cas, shed light on our general understanding of signal transduction, regulation of cell death/survival, and cell growth, and help designing therapeutic reagents to induce/prevent apoptosis in treating human diseases.

拟议研究计划的目标是研究p130 Cas在细胞生理学中未探索的重要功能，即，它在调节细胞死亡和存活中的作用。p130 Cas是一种多功能的细胞信号组装蛋白，最初被鉴定为v-Crk或v-Src转化细胞中的主要酪氨酸磷酸化蛋白。它含有多种结构基序，并与许多信号分子相互作用，如Crk，Src和FAK。 与其结构特征一致，p130 Cas已被发现在功能上参与细胞转化、粘附、迁移和肌动蛋白组织。 这对动物的正常发育至关重要。缺乏p130 Cas的突变小鼠在子宫内死亡，表现出明显的全身充血和生长迟缓。 然而，p130 Cas在细胞死亡/存活调节中的功能尚未研究。在我们对蛋白酪氨酸磷酸化和细胞生长调节的研究过程中，我们发现p130 Cas在酪氨酸磷酸酶LAR诱导的细胞凋亡中起关键作用。 LAR使p130 Cas蛋白去磷酸化和不稳定。 LAR下调p130 Cas蛋白表达，激活caspase通路，诱导细胞凋亡。 p130 Cas蛋白水平的恢复可抑制LAR诱导的细胞凋亡。这些数据表明p130 Cas在调节细胞死亡/存活中的新功能和p130 Cas蛋白调节的新机制。本研究旨在探讨p130 Cas在细胞死亡/存活调控中的作用和机制。 我们将使用生物化学，分子和细胞生物学技术的组合，以确定特定的信号分子和信号转导途径，通过p130 Cas转导细胞死亡/存活信号。 我们将研究p130 Cas介导的细胞死亡的生理相关性，通过检查p130 Cas在失巢凋亡过程中的调节和功能，失巢凋亡是上皮细胞和内皮细胞从其基质中脱落引起的细胞死亡的一种形式，在生长因子剥夺诱导的细胞死亡中，蛋白酪氨酸磷酸化/去磷酸化起着关键作用。 最后，对p130 Cas蛋白水平调控的新机制进行了探讨。 该研究将增加我们对p130 Cas的功能和机制的认识，阐明我们对信号转导、细胞死亡/存活调节和细胞生长的一般理解，并有助于设计治疗药物以诱导/预防细胞凋亡治疗人类疾病。