Mechanisms of regulation of actin-myosin interaction induced by remodeling of contractile filaments in living smooth muscle

2015 Fiscal Year Final Research Report

• Project/Area Number: 23500475
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Neurophysiology and muscle physiology
• Research Institution: Tokyo Metropolitan University
• Principal Investigator: WATANABE MASARU 首都大学東京, 人間健康科学研究科, 教授 (60191798)
• Co-Investigator(Renkei-kenkyūsha): ISHIDA YUKISATO 文京学院大学, 保健医療学部, 教授 (50092135)
• Project Period (FY): 2011-04-28 – 2016-03-31
• Keywords: 平滑筋 / 収縮フィラメント / リモデリング

Outline of Final Research Achievements

To explore the mechanisms of regulation of actin-myosin interaction induced by remodeling of contractile filaments in living smooth muscle, we examined X-ray diffraction studies and also force measurements in skinned (cell membrane permeabilized) smooth muscle. In skinned taenia cecum in the resting state, myosin-remodeling induced diffuse equatorial peak at 11.4 nm originated from lattice-like arrangement of the thin filaments, indicating that functional changes in smooth muscle myosin molecules regulate the organization of thick-filaments, resulting in the alteration of thin-filaments structure and/or organization even in the absence of cross-bridge formation.
Under the same experimental conditions, we found that myosin remodeling changed chemo-mechanical coupling of skinned taenia cecum, because such a stimuli accelerated relaxation processes by interference of latch-bridge formation.

Free Research Field

生理学