The role of c-Abl in T cell activation

描述（由申请人提供）：几乎T细胞功能的每个方面都依赖于肌动蛋白动力学的调节变化。我最近表明，Abelson激酶c-Abl是T细胞激活和迁移中适当的肌动蛋白反应所必需的。与此相一致的是，使用c-Abl缺陷小鼠的研究和使用Abl抑制剂伊马替尼治疗的患者的临床研究表明，Abl激酶功能是T细胞介导的有效免疫所必需的。然而，我们对c-Abl在T细胞中的正常作用知之甚少。我的长期职业目标是建立自己的研究利基，研究项目围绕了解c-Abl在免疫系统中的功能。我的直接目标是验证c-Abl通过调节肌动蛋白相关蛋白HS1和WAVE2的功能来调节T细胞激活的假设。为了验证这一假设，我将进行三个具体目标：1)由于定位是调节c-Abl功能的关键机制，我将成像c-Abl在免疫突触（is）的募集和激活，并分析T细胞中调节c-Abl定位的结构域。2)为了了解c-Abl如何调节HS1活性，我将确定c-Abl磷酸化HS1的位点，并评估这种磷酸化的功能后果。此外，我将分析c-Abl和HS1在活T细胞中的空间和功能相互作用。3)为了了解c-Abl如何与WAVE2相互作用，我将询问c-Abl是否磷酸化WAVE2或WAVE复合物组分，并分析c-Abl对活T细胞中WAVE2定位的调节作用。这些研究将在Janis Burkhardt博士的实验室进行，并将利用她的实验室以及费城儿童医院和宾夕法尼亚大学的优秀研究环境。我期望通过开展这个项目，我将获得研究原代T细胞反应的宝贵经验。特别是，我计划结合先进的成像和蛋白质分析工具，在蛋白质动力学和信号复合物形成的水平上解决T细胞信号传导的问题。这将帮助我进入重要的和未被充分研究的T细胞信号领域，并将为我的独立研究计划奠定基础。

DESCRIPTION (provided by applicant): Virtually every aspect of T cell function depends on regulated changes in actin dynamics. I have recently shown that the Abelson kinase c-Abl is required for appropriate actin responses in T cell activation and migration. In keeping with this, evidence from studies using c-Abl-deficient mice and clinical studies of patients treated with the Abl inhibitor imatinib indicate that Abl kinase function is required for effective T cell-mediated immunity. However, little is known about the normal role of c-Abl in T cells. My long-term career goal is to establish my own research niche, with a research program revolving around understanding c-Abl function in the immune system. My immediate goal is to test the hypothesis that c-Abl regulates T cell activation by regulating the function of the actin-associated proteins HS1 and WAVE2. To test this hypothesis, I will conduct three specific aims: 1) Since localization is a key mechanism by which c-Abl function is regulated, I will image c-Abl recruitment and activation at the immunological synapse (IS), and analyze the domains that regulate c- Abl localization in T cells. 2) To understand how c-Abl regulates HS1 activity, I will identify the sites where c- Abl phosphorylates HS1, and assess the functional consequences of this phosphorylation. In addition, I will analyze the spatial and functional interaction of c-Abl and HS1 in living T cells. 3) To understand how c-Abl interacts with WAVE2, I will ask if c-Abl phosphorylates WAVE2 or WAVE complex components, and analyze the regulatory role of c-Abl on WAVE2 localization in living T cells. These studies will be conducted in Dr. Janis Burkhardt's lab, and will draw upon the outstanding research environment in her lab and at the Children's Hospital of Philadelphia and University of Pennsylvania. I anticipate that by carrying out this project, I will gain valuable experience in studying primary T cell responses. In particular, I plan to use a combination of advanced imaging and protein analytical tools to address the problem of T cell signaling at the level of protein dynamics and signaling complex formation. This will help me to move into important and understudied areas of T cell signaling, and will form the foundation for my independent research program.