Abstract
This chapter describes a current perception of the molecular interactions regulating myofilament activity in heart cells. The focus is on the interaction between troponin-C (TnC), the Ca2+-receptor and troponin I (TnI), an inhibitory protein. It is this interaction that appears to form a molecular switch that turns on the thin filament. It will be seen that control of the actin-myosin reaction is not only through Ca2+-binding to TnC, but also through steric, cooperative and allosteric processes involving all of the main myofilament proteins-actin, myosin, tropomyosin (Tm), troponin T (TnT), TnC, and TnI. The process is modulated by covalent and non-covalent mechanisms. The process is altered in diverse myopathies and pathologies of the heart and is a target for pharmacological manipulation by a new class of inotropic agents, the “Ca2+-sensitizers”.
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© 1995 Springer Science+Business Media New York
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Solaro, R.J. (1995). Troponin C — Troponin I Interactions and Molecular Signalling in Cardiac Myofilaments. In: Sideman, S., Beyar, R. (eds) Molecular and Subcellular Cardiology. Advances in Experimental Medicine and Biology, vol 382. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-1893-8_12
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DOI: https://doi.org/10.1007/978-1-4615-1893-8_12
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