Signal Transduction Pathways of Smooth Muscle

平滑肌的信号转导途径

• 批准号: 6853376
• 负责人: Avril V. Somlyo
• 金额: $ 47.06万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-01 至 2009-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6853376
• 关键词: RNA interference; bronchomotion; calcium flux; flash photolysis; guanine nucleotide binding protein; guanosinetriphosphatases; laboratory rabbit; muscle contraction; myosin light chain kinase; nucleoside phosphate kinase; phosphomonoesterases; phosphoprotein phosphatase; phosphorylation; protein isoforms; protein structure function; smooth muscle; vascular smooth muscle; vasomotion; yeast two hybrid system

The overall Aim of this Project is to determine the physiologically relevant mechanisms of signal transduction that regulate contractility by pathways not dependent on cytoplasmic Ca concentration. The domain dependent functions of the upstream regulators of Ca?+-sensitization by the RhoA-Rho kinase pathway, the guanine nucleotide exchange factors (GEFs) PDZ.RhoGEF and LARG, will be determined in conjunction with the structural identification and recombinant expression of GEF domains in Project 2. The role of a membrane associated protein (p120 catenin) as a potential RhoA-binding partner guanine nucleotide dissociations inhibitor (GDI) will be determined. The kinetics of myosin phosphatase regulation by Rho-kinase and its dependence on the expression level of the endogenous phosphatase inhibitor, CP1-17 will be quantitated in order to determine their relative physiological relevance. The dependence of myosin phosphatase activity on the specific long and short splice isoforms of the regulatory subunit (MYPT1) expressed in mammalian smooth muscle will be evaluated, based on the hypothesis that expression levels of the ratio of the two isoforms determine localization of the phosphatase and the mechanism of its regulation through differences in their phosphorylation sites and myosin binding properties. A major, novel, objective of this Project is to determine the functions of a protein, LPP, newly discovered to be selectively expressed in smooth muscle, on cellular phenotypes, including morphology, adhesion to substrate, cytoskeletal structure and motility. Localization and stimulus induced translocation of signaling proteins, co-localization of proteins, such as p120 catenin with RhoA or CP1-17 with myosin phosphatase or telokin and telokin and LPP partners identified in two-hybrid screens will be performed in Project 3. p120 catenin, LPP, recombinant RhoA, telokin, RhoA- and other protein-mutants will be supplied by Core B. Abnormalities of the RhoA pathway are thought to be involved in asthma and hypertension.

该项目的总体目的是确定信号的生理相关机制 通过途径调节收缩性的转导不取决于细胞质Ca浓度。 Rhoa-Rho激酶途径的CA？+敏化的上游调节剂的域依赖性功能，鸟嘌呤核苷酸交换因子（GEFS）PDZ.RHOGEF和LARG将与结构鉴定和gef在Project 2的结构识别和重组型蛋白（P1）的作用2. P​​. ef ew of Project os As a proje of Membrane of Protip os a prodection（P.将确定RhoA结合伴侣鸟嘌呤核苷酸分离抑制剂（GDI）。 Rho-激酶调节肌球蛋白磷酸酶的动力学及其对内源性磷酸酶抑制剂表达水平的依赖性，CP1-17将被定量以确定其相对生理相关性。基于假设，两个同工型的表达水平确定了确定的定位，将评估肌球蛋白磷酸酶活性对在哺乳动物平滑肌中表达的调节亚基（MYPT1）（MYPT1）（MYPT1）（MYPT1）的依赖性。 通过其磷酸化位点和肌球蛋白结合特性的差异，磷酸酶及其调节的机制。该项目的一个主要，新颖的目标是确定蛋白质，LPP的功能，新发现，在平滑肌，细胞表型中有选择地表达，包括形态学，对底物的粘附，细胞骨架结构和运动性。信号蛋白的局部定位和刺激诱导的易位，蛋白质的共定位，例如与RhoA或CP1-17的p120蛋白质与肌球蛋白磷酸酶或telokin，telokin和telokin及其LPP伴侣在两个杂交筛选中确定的蛋白质，将在Project 3中进行。由核心B提供的Rhoa途径异常是 被认为参与哮喘和高血压。