STRUCTURAL BIOLOGY OF CARDIOVASCULAR PROTEINS

这个跨学科计划的目的是确定结构- 蛋白质的功能关系和机制在正常 心血管功能和易受导致疾病的异常。 主要组成部分（项目1、3和4）涉及机制和结构 小GTP结合蛋白RhoA、其效应蛋白及其 监管机制。RhoA调节血管平滑肌 收缩，心肌肥大和应力纤维的形成，及其 唐斯效应物Rho激酶，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，它们的原子结构在项目3中确定， 它们在项目4中的亚细胞定位，主要是蛋白质 在核心B中产生。Ca/2+-脱敏蛋白的作用机制， telokin，将在项目1和3中确定，它是亚细胞的 在Project 4中。肌球蛋白的分子结构， 下游目标的主要RhoA介导的调控过程中顺利 肌肉，将确定与冷冻原子力显微镜，一种新的 方法开发的研究人员在这个程序（项目2）。这些 研究还将确定相互作用的结构基础， RhoA调节的平滑肌肌球蛋白磷酸酶，具有天然双头 肌球蛋白分子和肌球蛋白分子的构象在 跨桥周期介导收缩。该计划将完成 开发了一种功能强大的结构化方法，能量过滤扫描 透射电子显微镜（STEM-EELS），旨在获得 纳米分辨率的细胞组成信息 钙的分布、运动和其他元素。该方法 将用于定量绘制与心脏和血管 平滑肌细胞膜，并积累在线粒体和其他 细胞器，并将这些发现的正常功能， 钙的异常作用。低温原子力显微镜工作在 环境压力和中间高压场发射枪- 配备STEM-EELS系统和非常紧密的跨学科 结构生物学家和细胞生理学家之间的合作 几乎是这个计划的独特资源和功能。的高水平 生物医学意义的这是来自参与的 哮喘和高血压中的平滑肌调节蛋白，以及 从钙在心室发育中的重要性 纤维性颤动是心脏性猝死的最常见原因。

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.