학술논문
Crossbridge Recruitment Capacity of Wild-Type and Hypertrophic Cardiomyopathy-Related Mutant Troponin-T Evaluated by X-ray Diffraction and Mechanical Study of Cardiac Skinned Fibers.
Document Type
Academic Journal
Author
Yamaguchi M; Department of Physiology, The Jikei University School of Medicine, Tokyo 105-8461, Japan.; Kimura M; Department of Integrated Physiology, Kagawa Nutrition University, Saitama 350-0288, Japan.; Ohno T; Department of Sports Medicine, Teikyo Heisei University, Chiba 290-0193, Japan.; Nakahara N; Department of Physiology, The Jikei University School of Medicine, Tokyo 105-8461, Japan.; Akiyama N; Core Research Facilities for Basic Science, The Jikei University School of Medicine, Tokyo 105-8461, Japan.; Takemori S; Department of Physiology, The Jikei University School of Medicine, Tokyo 105-8461, Japan.; Yagi N; Spectroscopy and Imaging Division, Japan Synchrotron Radiation Research Institute, SPring-8 679-5198 Hyogo, Japan.
Source
Publisher: MDPI Country of Publication: Switzerland NLM ID: 101092791 Publication Model: Electronic Cited Medium: Internet ISSN: 1422-0067 (Electronic) Linking ISSN: 14220067 NLM ISO Abbreviation: Int J Mol Sci Subsets: MEDLINE
Subject
Language
English
Abstract
X-ray diffraction and tension measurement experiments were conducted on rat left ventricular skinned fibers with or without "troponin-T treatment," which exchanges the endogenous troponin T/I/C complex with exogenous troponin-T. These experiments were performed to observe the structural changes in troponin-T within a fiber elicited by contractile crossbridge formation and investigate the abnormality of hypertrophic cardiomyopathy-related troponin-T mutants. The intensity of the troponin reflection at 1/38.5 nm -1 was decreased significantly by ATP addition after treatment with wild-type or mutant troponin-T, indicating that crossbridge formation affected the conformation of troponin-T. In experiments on cardiac fibers treated with the hypertrophic cardiomyopathy-related mutants E244D- and K247R-troponin-T, treatment with K247R-troponin-T did not recruit contracting actomyosin to a greater extent than wild-type-troponin-T, although a similar drop in the intensity of the troponin reflection occurred. Therefore, the conformational change in K247R-troponin-T was suggested to be unable to fully recruit actomyosin interaction, which may be the cause of cardiomyopathy.
Competing Interests: The authors declare no conflict of interest.
Competing Interests: The authors declare no conflict of interest.