STRUCTURAL BIOLOGY OF CARDIOVASCULAR PROTEINS

这个跨学科项目的目标是确定结构-- 正常组织中重要蛋白质的功能关系和机制 心血管功能异常，容易引起疾病。 主要组成部分(项目1、3和4)涉及机制和结构 小分子GTP结合蛋白RhoA及其效应蛋白的研究进展 监管机制。RhoA对血管平滑肌的调节作用 收缩、心肌肥厚和应力纤维的形成及其 唐斯流效应器，Rho-Kinase，最近被牵连到 高血压。RhoA及其相关蛋白的细胞机制 将在项目1中确定，其原子结构在项目3中确定，以及 它们在项目4中的亚细胞定位，主要是蛋白质 产生于核心B。钙/2+脱敏蛋白的机制， Telokin，将在项目1和3中确定，它是亚细胞的 项目4.肌球蛋白的分子结构的定位，最终 RhoA介导的主要调控过程的下游靶点 肌肉，将用冷冻原子力显微镜来测定，这是一种新的 本项目(项目2)中的一名研究人员开发的方法。这些 研究还将确定相互作用的结构基础 RhoA调节的天然双头肌肌球蛋白磷酸酶 肌球蛋白分子与肌球蛋白分子的构象 调节收缩的跨桥周期。程序将完成 发展了一种强大的结构方法--能量过滤扫描 透射电子显微镜(STEM-EELS)，旨在获得 关于细胞的纳米分辨率的组成信息 钙的分布，它的运动和其他元素。这种方法 将被用来定量绘制与心脏和血管结合的钙 平滑肌细胞膜，并积聚在线粒体等 并将这些发现评定为正常功能和 钙的异常作用。低温原子力显微镜工作在 环境压力和中高压、场发射枪- 装备STEM-EELS系统和非常紧密的学科交叉 结构生物学家和细胞生理学家之间的合作是 这个节目几乎是独一无二的资源和特点。高水平的 这一点的生物医学意义源于 哮喘和高血压中的平滑肌调节蛋白，以及 从钙在脑室发育中的重要性谈起 纤颤是心源性猝死最常见的原因。

The aim of this interdisciplinary program is to determine the structure- function relationships and mechanisms of proteins important in normal cardiovascular function and subject to abnormalities that cause disease. Major components (Projects 1, 3 and 4) address the mechanism and structure of the small GTP-binding protein RhoA, its effector proteins and its mechanisms of regulation. RhoA regulates vascular smooth muscle contraction, cardiac hypertrophy and formation of stress fibers, and its downs stream effectors, Rho-kinase, was recently implicated in hypertension. The cellular mechanisms of RhoA and Rho-related proteins will be determine in Project 1, their atomic structures in Project 3, and their subcellular localization in Project 4, with proteins largely produced in Core B. The mechanisms of Ca/2+-desensitization protein, telokin, will be determined in Projects 1 and 3, and it sub-cellular localization in Project 4. The molecular structure of myosin, the final downstream target of the major RhoA-mediated regulatory process in smooth muscle, will be determined with cryo-atomic force microscopy, a novel method developed by an investigator in this program (Project 2). These studies will also determine the structural bases of the interaction of the RhoA-regulated, smooth muscle myosin phosphatase with native, two-headed myosin molecules and the conformation of the myosin molecule during the cross bridge cycle that mediates contraction. The program will complete the development of a powerful structural method, energy filtered scanning transmission electron microscopy (STEM-EELS), that is designed to obtain compositional information at nanometer resolution about the cellular distribution of calcium, its movements and of other elements. This method will be used to quantitatively map calcium bound to cardiac and vascular smooth muscle cell membranes, and accumulated in mitochondria and other cell organelles and will rate these findings to the normal functions and abnormal effects of calcium. The cryo-atomic force microscope operating at ambient pressure and the intermediate high voltage, field emission gun- equipped STEM-EELS system and the very close interdisciplinary collaborations between structural biologists and cell physiologists are almost unique resources and features of this program. The high level of biomedical significance of this is derived from the involvement of the smooth muscle regulatory proteins in asthma and high blood pressure, and from the importance of calcium in the development of ventricular fibrillation, the most common cause of sudden cardiac death.