The role of Akt in platelet signaling and thrombosis

描述(由申请人提供)： 我的长期职业目标是在一家大型研究机构获得一个教员职位，那里的资源足以支持糖尿病血管并发症的研究专业。我的短期目标是利用这一研究职业奖助金支持的项目，发展作为一名研究人员的日益独立的能力，并拓宽我在信号转导和血小板生物学方面的发展专长，包括更全面地了解血小板在体内的作用。Brass博士在宾夕法尼亚大学医学部Hem-ONC分部的实验室为管理科学和职业过渡提供了理想的环境。科学上，每周一次的数据俱乐部和由当地血小板生物学、糖尿病、血液学和药理学专家举办的研讨会系列为讨论每个专业的当前发展提供了活跃的论坛，其中许多导致了卓有成效的合作。关于我的职业发展，我的赞助人和医学主席都致力于支持我在3年内过渡到正式的教员职位。这一建议的科学目标是了解调节血小板激活的细胞内信号事件，以更好地了解它们对血栓形成的贡献。在以下3个具体目标中，该提议将检验Akt1和Akt2在导致体内形成的血小板聚集和稳定的信号通路中发挥关键作用的假设。 目的1)Akt在体外是否促进了血小板的活化和聚集？这些研究将继续我已经开始的工作，以确定缺乏Akt1和Akt2多个等位基因的小鼠是否在纤维蛋白原结合、颗粒分泌或凝块回缩方面存在缺陷。 目的2)Akt如何参与导致血小板活化的信号通路？血小板Akt的低表达对整合素αLibβ3的GTPase Rap1的激活和β3尾部的磷酸化的影响将被测试，因为这些事件与血小板聚集有关。 目的3)Akt在体内对血小板堵塞的形成有贡献吗？我们将测量Akt缺陷小鼠和野生型小鼠的出血时间、三氯化铁损伤颈动脉后的血流量和血栓栓塞症，以确定Akt对止血和血栓形成的影响。

DESCRIPTION (provided by applicant): My long-term career objectives are to obtain a faculty position at a major research institution, where the resources exist to support a research specialty in the vascular complications of diabetes. My short-term goals are to use the project supported by this research career grant award both to develop increasing independence as an investigator and to broaden my developing expertise in signal transduction and platelet biology to include a more complete understanding of the role of the platelet in vivo. The laboratory of Dr. Brass here in the Hem-Onc Division of the Department of Medicine at Penn provides an ideal environment in which to manage both the scientific and career transition. Scientifically, weekly data clubs and seminar series run by local experts in platelet biology, diabetes, hematology, and pharmacology provide lively forums for discussion of the current developments in each specialty, many of which lead to fruitful collaborations. With regard to my career development, both my sponsor and the Chair of Medicine are committed to supporting my transition to a full faculty position within 3 years. The scientific objective of this proposal is to understand the intracellular signaling events that regulate platelet activation to gain a better understanding of their contribution to thrombosis. In the following 3 Specific Aims, this proposal will test the hypothesis that Akt1 and Akt2 play a critical role in the signaling pathways that lead to platelet aggregation and stabilization of the platelet plug formed in vivo. Aim 1) Does Akt contribute to platelet activation and platelet aggregation in vitro? These studies will continue work that I have already begun to determine whether mice lacking multiple alleles of Akt1 and Akt2 have defects in fibrinogen binding, granule secretion, or clot retraction. Aim 2) How is Akt involved in signaling pathways leading to platelet activation? The effects of low expression of platelet Akt on activation of the GTPase Rap1 and phosphorylation of the beta 3 tail of integrin alpha lIb beta 3 will be tested since these events have been associated with platelet aggregation. Aim 3) Does Akt contribute to platelet plug formation in vivo? We will measure bleeding time, blood flow after ferric chloride injury of the carotid artery, and thromboembolism in Akt-deficient versus wildtype mice to determine the effect of Akt on hemostasis and thrombosis.