Converge of Pathways Regulating SMC Contractility

调节 SMC 收缩性途径的汇聚

• 批准号: 7746392
• 负责人: Avril V. Somlyo
• 金额: $ 62.57万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7746392
• 关键词: ATP-sepharose; Accounting; Actomyosin; Actomyosin Adenosinetriphosphatase; Address; Affect; Affinity; Animals; Aorta; Atherosclerosis; Binding; Biochemical; Biological Assay; Calmodulin; Cells; Cerebrovascular Spasm; Characteristics; Collaborations; Collagen; Complex; Contracts; Coronary Restenosis; Coronary Vessels; Coupling; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Cyclic Nucleotides; Cytokinesis; Defect; Development; Embryo; Embryonic Development; Figs - dietary; Filament; Fluorescence; Gel; Gene Expression Regulation; Gene Targeting; Generations; Goals; Growth; Heart; Hypertension; Kinetics; Knockout Mice; Laboratories; Lead; Maintenance; Measures; Mechanics; MgADP; Microfilaments; Modeling; Motor; Mus; Muscle; Myocardium; Myosin ATPase; Myosin Light Chain Kinase; Myosin Regulatory Light Chains; Myosin Type I; Nucleotides; Organ; Organ Culture Techniques; Outcome; Pathway interactions; Peptides; Phase; Phenotype; Phosphorylation; Phosphotransferases; Physiological; Play; Population; Principal Investigator; Process; Protein Dephosphorylation; Protocols documentation; Rattus; Regulation; Relaxation; Reporting; Resolution; Reverse Transcriptase Polymerase Chain Reaction; Role; Sarcomeres; Shock; Signal Pathway; Signal Transduction; Smooth Muscle; Smooth Muscle Actin Staining Method; Smooth Muscle Myosins; Staging; Stem cells; Testing; Thick Filament; Thymus Gland; Time; Vascular Smooth Muscle; Visceral; Western Blotting; analog; base; cell motility; embryonic stem cell; inhibitor/antagonist; migration; myosin phosphatase; novel; nucleotide analog; photolysis; precursor cell; programs; promoter; protein expression; receptor; research study; response; skeletal; telokin; tissue culture

The overall goal of this Project is to understand the complex processes that regulate contractility in vascular smooth muscle under physiological and pathophysiological conditions, which lead to high blood pressure, atherosclerosis, coronary restenosis, shock or cerebral vasospasm. Contractility is switched on in smooth muscle (SM) via phosphorylation of the regulatory light chain of myosin (RLC) and the level of phosphorylation is dependent upon the opposing activities of the Ca2+/calmodulin dependent myosin light chain kinase (MLCK) and myosin light chain phosphatase, both of which can be regulated by upstream signaling pathways. We, with Project 2, have generated MLCK null mice, which are embryonic lethal, starting at E15.5 with some reaching term, but prior to this embryonic aortae or umbilical vessels display RLC phosphorylation and normal force development in response to Ca 2+. We will test the hypothesis that ubiquitously expressed SM MLCKs are critical for contraction, migration, filament and sarcomere formation in smooth and cardiac muscle respectively, as well as A404SMC "progenitor" cells (Project 2, Core A) and transformed proepicardial cells (Project 3, Core A); or alternatively that a compensatory kinase(s) accounts for the MLCK activity in MLCK null embryos or that another kinase normally predominants during embryonic development. Preliminary studies suggest that formation of the coronary vessels is defective in MLCK null embryos, thus, we will test the hypothesis that MLCKs are critical for migration of the epicardial cells of the proepicardial organ, the precursors of the coronary vessels with Project 3. The myosin motors underlying cell migration and contractility are also regulated and contribute to the SM contractile phenotype. These mechanisms will be explored using kinetic analysis with a novel recently synthesized fluorescent 3'-amino derivative of ATP. We will test the hypothesis that AM. ADP strongly bound crossbridges play a significant role in maintaining tonic force at low actomyosin activity, slow shortening velocity and low levels of RLC phosphorylation, characteristic features of SM myosins. The proposed studies require extensive interactions with the other projects and Core A and match the central theme of this PPG.

该项目的总体目标是了解在生理和病理生理条件下调节血管平滑肌收缩力的复杂过程，从而导致高血压，动脉粥样硬化，冠状动脉再狭窄，休克或脑血管痉挛。通过肌球蛋白（RLC）调节轻链的磷酸化，在平滑肌（SM）中打开收缩力，磷酸化水平取决于Ca2+/钙调蛋白肌球蛋白光链轻链激酶（MLCK）的相对活性（MLCK）和肌球蛋白轻链酶磷酸化酶，这两种磷酸酶磷酸化酶的磷酸磷酸化酶，这两个磷酸磷酸酶都可以根据上层的范围来调节。我们使用项目2产生了胚胎致死的MLCK null小鼠，从E15.5开始，有一些达到术语，但是在此胚胎主动脉或脐带血管之前，我们显示出RLC磷酸化和向师力的发育，响应于Ca 2+。我们将检验以下假设：普通和心脏肌肉中分别对收缩，迁移，细丝和肌节形成至关重要，以及A404SMC“祖细胞”细胞（Project 2，core a）和转化的ProEpicardial细胞（Project 2，Project o Core A）（Project 3，Core 3，Core A）；或者，代偿性激酶（S）解释了MLCK无效胚胎的MLCK活性，或者是胚胎发育过程中另一种激酶通常为主要的激酶。初步研究表明，冠状血管的形成在MLCK无效胚胎中有缺陷，因此，我们将检验以下假设：MLCK对于促头皮器官的心外膜细胞的迁移至关重要，冠状器官的前体的前体是带有Project 3的细胞迁移和合同的肌电蛋白动力和缩水量。这些机制将使用动力学分析来探索使用新颖 最近合成ATP的荧光3'-氨基衍生物。我们将检验AM的假设。 ADP强烈结合的跨桥在维持低肌动球蛋白活性，缩短速度缓慢和RLC磷酸化水平较低的情况下，SM肌球蛋白的特征性特征的较慢，起着重要作用。拟议的研究需要与其他项目和核心A进行广泛的互动，并与该PPG的中心主题相匹配。