Platelet granule exocytosis and thrombus formation

血小板颗粒胞吐作用和血栓形成

基本信息

批准号：
8605908
负责人：
Robert C Flaumenhaft
金额：
$ 42.63万
依托单位：
BETH ISRAEL DEACONESS MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-02-01 至 2017-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8605908
关键词：
Actins Address Adhesions Alpha Granule Blood Platelets Cells Coagulation Process Cytoplasmic Granules Cytoskeleton Disease Dynamin Dynamin 2 Dynamin III Evaluation Event Exocytosis Foundations Genetic Screening Hemostatic function Heterogeneity In Vitro Individual Inflammation Kinetics Laboratories Learning Malignant Neoplasms Mediating Membrane Membrane Fusion Molecular Molecular Chaperones Monitor Morbidity - disease rate Movement Mus Myocardial Infarction Platelet Activation Population Protein Isoforms Proteins Regulation Role SNAP receptor Sorting - Cell Movement Speed Stroke Structure Suspension substance Suspensions Thrombosis Thrombus Vascular Diseases Video Microscopy Wound Healing angiogenesis cellubrevin chaperone machinery chemical genetics controlled release in vivo intravital microscopy mortality neglect novel protein function public health relevance research study segregation trafficking vesicle-associated membrane protein

项目摘要

DESCRIPTION (provided by applicant): Granule exocytosis is an essential platelet function, contributing not only to hemostasis and thrombosis, but also to inflammation, wound healing, malignancy, and angiogenesis. Previous efforts to understand the molecular mechanisms of granule exocytosis have identified the SNARE machinery and chaperone proteins required for membrane fusion. Studies described in this proposal will evaluate the premise that this machinery serves a role in sorting specific cargos to distinct subpopulations of ¿-granules and enabling differential release of granule contents upon platelet activation. We will study granule segregation and secretion in mice lacking VAMP-3, VAMP-5, VAMP-7, and VAMP-8. Cytoskeleton dynamics that occur during platelet spreading can influence SNARE interactions and modify granule exocytosis. We will evaluate granule exocytosis during platelet spreading. These studies will also assess the role of exocytosis in providing membrane for growing actin structures at the periphery of adherent platelets and for directed spreading and movement on micropatterned matrices of adhesion proteins. Use of high-speed intravital microscopy will be used to monitor release of granules from individual platelets during thrombus formation in vivo. These approaches will allow us to evaluate the hypothesis that the mechanism of granule secretion is altered in adherent platelets compared to suspension platelets. We will also evaluate the role of dynamins in controlling fusion pore dynamics, demonstrating a level of control of platelet exocytosis that occurs following SNARE-mediated membrane fusion. These studies will use single-cell amperometry to monitor the release of individual granules from single platelets. The role of dynamins in controlling platelet exocytosis during thrombus formation in vivo will evaluate the hypothesis that the platelet fusion pore can be regulated to control thrombus formation. These experiments will address poorly understood aspects of platelet granule exocytosis and provide a foundation for targeting select platelet membrane fusion events during thrombosis.

描述（由适用提供）：颗粒胞吐作用是必不可少的血小板功能，不仅导致止血和血栓形成，还导致炎症，伤口愈合，恶性肿瘤和血管生成。以前了解颗粒胞吐作用的分子机制的努力已经确定了膜融合所需的圈圈机制和伴侣蛋白。该提案中描述的研究将评估该机械在将特定的嘉戈斯分类为存在的不同亚群中的作用，并在血小板激活后使颗粒含量的差异释放。我们将研究缺乏VAMP-3，VAMP-5，VAMP-7和VAMP-8的小鼠的颗粒分离和分泌。在血小板扩散期间发生的细胞骨架动力学会影响核心相互作用并改变颗粒胞吐作用。我们将评估血小板扩散期间颗粒胞吐作用。这些研究还将评估胞吐作用在为粘合剂血小板周围生长的肌动蛋白结构提供膜上的作用，并在粘合蛋白的微图案材料上进行定向扩散和运动。在体内血栓形成期间，使用高速浸润显微镜将用于监测单个血小板的颗粒释放。这些方法将使我们能够评估以下假设：与悬浮血小板相比，粘合剂血小板中颗粒分泌的机制发生了变化。我们还将评估动态蛋白在控制融合孔动力学中的作用，证明在循环介导的膜融合后发生的血小板胞吐作用水平。这些研究将使用单细胞安培法监测单个血小板的单个颗粒的释放。在体内血栓形成过程中，动力蛋白在控制血小板胞吐作用中的作用将评估可以调节血小板融合孔以控制血栓形成的假设。这些实验将解决缺乏血小板颗粒胞吐作用的方面，并为靶向血栓形成期间精选血小板膜融合事件的基础。