Membrane-Cytoskeletal Remodeling in Platelet Biogenesis

血小板生物发生中的膜细胞骨架重塑

• 批准号: 9032516
• 负责人: Yolande Chen
• 金额: $ 9.19万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2020-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9032516
• 关键词: Actins; Address; Affect; Animal Model; Autoimmunity; Award; Banana; Binding; Biochemistry; Biogenesis; Biophysics; Blood; Blood Cells; Blood Platelets; Blood flow; C-terminal; Cancer Cell Growth; Cardiovascular Diseases; Cardiovascular system; Cell membrane; Cells; Cellular biology; Clinical; Data; Defect; Development; Discontinuous Capillary; Disease; Dynamin; Endocytic Vesicle; Event; Goals; Health; Hematologist; Hematopoiesis; Hemorrhage; Hemostatic function; Human; Image; Infarction; Infection; Inflammation; Inflammatory; Instruction; International; Intracellular Membranes; K-Series Research Career Programs; Knock-out; Knockout Mice; Laboratories; Lead; Link; Lipid Binding; Malignant Neoplasms; Mediating; Megakaryocytes; Membrane; Membrane Lipids; Mentors; Mentorship; Morbidity - disease rate; Mus; N-terminal; Pathogenesis; Pathway interactions; Patients; Physicians; Physiological; Plasma; Platelet Activation; Platelet Count measurement; Play; Production; Proteins; Research; Research Personnel; Research Training; Role; SH3 Domains; Schools; Scientist; Shapes; Stroke; System; TRIP10 gene; Thrombocytopenia; Thrombosis; Time; Training; United States; Universities; Variant; Wiskott-Aldrich Syndrome; Yeasts; amphiphysin; career; cellular imaging; defined contribution; dimer; fascinate; human disease; improved; insight; knock-down; laboratory experience; meetings; mortality; neoplastic; novel; prevent; skills; src-Family Kinases; trafficking; yeast two hybrid system

 DESCRIPTION (provided by applicant): Project Summary Defects in platelet production and function play substantial roles in cardiovascular, bleeding, and inflammatory diseases. More complete understanding of platelet biogenesis will yield insights and advances in human health. My mentor's lab discovered a new cytoskeletal component, Cdc42-interacting protein 4 (CIP4), in a yeast two-hybrid screen with the Src kinase Lyn as bait. CIP4 is a BAR protein that coordinates membrane and cytoskeletal remodeling. Through its SH3 domain, CIP4 interacts with Wiskott-Aldrich Syndrome Protein (WASP) or dynamin. Wiskott-Aldrich Syndrome is characterized by thrombocytopenia. My lab generated CIP4-knockout (KO) mice that displayed thrombocytopenia. I determined that the mechanism for thrombocytopenia in CIP4-KO mouse megakaryocytes involves decreased proplatelet formation and reduced demarcation membrane system, which are not observed in WASP-KO mouse megakaryocytes. In addition, unlike WASP-KO mice, CIP4 KO mice show decreased platelet-microparticle release into the plasma. I hypothesize that CIP4-dependent thrombocytopenia involves dynamin. Surprisingly, cells with dynamin knockdown showed increased microparticle release. Since dynamin's chief role is to promote endocytic vesicle formation, this variation of membrane scission mediated by dynamin would be novel. The goal of my proposed research is to determine the mechanism by which CIP4-dynamin pathway regulates membrane remodeling in normal platelet biogenesis and how this may impact platelet biogenesis. I hypothesize that loss of dynamin, affects membrane intracellular trafficking in megakaryocytes, resulting in more membrane being available for demarcation membrane system invagination and for microparticle release. To address this hypothesis, I propose the following two specific aims: 1) establish that loss of dynamin promotes formation of the demarcation membrane system and 2) define the thrombogenic potential from microparticles produced by megakaryocytes/platelets with reduced dynamin activity. This proposal combines cell biology, biochemistry, biophysics, and advanced imaging with animal modeling to establish a new pathway of membrane remodeling in platelet biogenesis and thrombogenesis. This K08 award provides me with intensive laboratory training, mentorship, and committee oversight so that I can successfully develop into an independent physician- scientist. Research and training plan will be carried at Northwestern University under the mentorships of Drs. Seth Corey and Susan Quaggin with graduate school coursework in cell biology and advice from a committee of well-established investigators in platelet biogenesis (Joseph Italiano), thrombogenesis (Xiaoping Du) and hematopoiesis (Liz Eklund).

 描述（由申请人提供）：项目概述血小板生成和功能缺陷在心血管、出血和炎症性疾病中起重要作用。对血小板生物发生的更全面的了解将产生对人类健康的见解和进步。我导师的实验室在以Src激酶林恩为诱饵的酵母双杂交筛选中发现了一种新的细胞骨架成分，即Cdc 42相互作用蛋白4（CIP 4）。CIP 4是协调膜和细胞骨架重塑的BAR蛋白。通过其SH 3结构域，CIP 4与Wiskott-Aldrich综合征蛋白（WASP）或发动蛋白相互作用。Wiskott-Aldrich综合征的特征是血小板减少症。我的实验室产生了CIP 4敲除（KO）小鼠，显示血小板减少症。本人确定，CIP 4-KO小鼠巨核细胞中血小板减少的机制涉及前血小板形成减少和分界膜系统减少，这在WASP-KO小鼠巨核细胞中未观察到。此外，与WASP-KO小鼠不同，CIP 4 KO小鼠显示血小板微粒释放到血浆中减少。我推测CIP 4依赖性血小板减少症与发动蛋白有关。令人惊讶的是，发动蛋白敲低的细胞显示出增加的微粒释放。由于发动蛋白的主要作用是促进内吞囊泡的形成，因此这种由发动蛋白介导的膜断裂变化将是新颖的。我提出的研究的目标是确定CIP 4-动力蛋白途径调节正常血小板生物发生中的膜重塑的机制，以及这可能如何影响血小板生物发生。我推测，发动蛋白的损失，影响巨核细胞的膜细胞内运输，导致更多的膜可用于分界膜系统内陷和微粒释放。为了解决这一假设，我提出了以下两个具体目标：1）建立动力蛋白的损失促进分界膜系统的形成和2）定义由巨核细胞/血小板产生的微粒与减少动力蛋白活性的血栓形成的潜力。该建议将细胞生物学、生物化学、生物物理学和先进的成像与动物建模相结合，以建立血小板生物生成和血栓形成中膜重塑的新途径。这个K 08奖为我提供了密集的实验室培训，指导和委员会监督，使我能够成功地发展成为一个独立的医生-科学家。研究和培训计划将在西北大学Seth Corey和Susan Quaggin博士的指导下进行，研究生院的细胞生物学课程以及血小板生物发生（Joseph Italiano），血栓形成（Xiaoping Du）和造血（Liz Eklund）方面的知名研究人员委员会的建议。