CALPONIN--ITS ROLE IN SMOOTH MUSCLE REGULATION

钙调蛋白——其在平滑肌调节中的作用

• 批准号: 6434898
• 负责人: Terence Tao
• 金额: $ 27.63万
• 依托单位: BOSTON BIOMEDICAL RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-04-01 至 2001-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6434898
• 关键词: actins; active sites; affinity chromatography; analytical ultracentrifugation; animal tissue; calponin; cell type; chemical binding; conformation; crosslink; cytoskeleton; enzyme linked immunosorbent assay; ferrets; fibrous protein; fluorescent dye /probe; gel filtration chromatography; gene deletion mutation; gene targeting; genetically modified animals; histology; laboratory mouse; laboratory rabbit; muscle contraction; muscle proteins; myosins; organ culture; protein isoforms; protein localization; protein sequence; protein structure function; smooth muscle; tropomyosin

The long term objective of this subproject is to decipher the role of calponin (CaP) in the regulation of smooth muscle contraction. The biochemical properties of CaP strongly suggest that it can regulate the contractility of smooth muscle by modifying the interaction between actin and myosin. Results of experiments using exogenously added CaP or CaP antagonist seem to support this notion. On the other hand, in situ localization studies show that Cap is primarily localized in the cytoskeletal rather than the actomyosin regions of chicken gizzard cells. These findings suggest several possibilities: 1) CaP is localized in the actomyosin regions in the relaxed state where it functions by inhibiting actin-myosin interaction; upon stimulation it migrates out of the actomyosin regions to the cytoskeletal regions. 2) CaP is not localized in the actomyosin regions regardless of contractile state and type of tissue; instead, it is localized in the cytoskeletal regions where it modulates contractibility via the cytoskeleton. 3) CaP is not involved in contractibility. In this process we will test these possibilities by carrying out the following experiments: 1) Determine the in situ localization of CaP as a function of contractile state and cell type. 2) Determine the in vivo stoichiometries of CaP and various contractile and cytoskeletal proteins. 3) Study the interaction between CaP and various smooth muscle proteins. 4) Determine the effects of CaP and CaP antagonists on the contractility and cytoskeletal structure of smooth muscle cells. Results derived from this project may reveal the true physiological function of CaP and uncover novel concepts in smooth muscle physiology such as the involvement of the cytoskeleton in contractility.

该子项目的长期目标是阐明 钙调蛋白 (CaP) 调节平滑肌收缩。这 CaP 的生化特性强烈表明它可以调节 通过改变肌动蛋白之间的相互作用来调节平滑肌的收缩性 和肌球蛋白。使用外源添加的CaP或CaP的实验结果 对手似乎支持这个观点。另一方面，在原地 本地化研究表明，Cap 主要本地化于 细胞骨架而不是鸡砂囊细胞的肌动球蛋白区域。 这些发现提出了几种可能性：1）CaP 位于 肌动球蛋白区域处于松弛状态，其功能是通过抑制 肌动蛋白-肌球蛋白相互作用；受到刺激后，它会迁移出 肌动球蛋白区域到细胞骨架区域。 2）CaP 不本地化 肌动球蛋白区域，无论收缩状态和组织类型如何； 相反，它位于调节的细胞骨架区域 通过细胞骨架的收缩性。 3）CaP不参与 收缩性。在此过程中，我们将通过以下方式测试这些可能性 进行以下实验： 1) 确定原位 CaP 的定位作为收缩状态和细胞类型的函数。 2） 确定 CaP 和各种收缩和收缩的体内化学计量 细胞骨架蛋白。 3）研究CaP与各种物质之间的相互作用 平滑肌蛋白。 4) 确定CaP和CaP的影响 平滑肌收缩力和细胞骨架结构的拮抗剂 肌肉细胞。该项目的结果可能会揭示真实的情况 CaP 的生理功能并揭示平滑肌的新概念 生理学，例如细胞骨架参与收缩性。