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The Special Structure and Function of Troponin I in Regulation of Cardiac Contraction and Relaxation

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Molecular and Cellular Aspects of Muscle Contraction

Part of the book series: Advances in Experimental Medicine and Biology ((AEMB,volume 538))

Abstract

In this chapter I review evidence for a pivotal role of the sarcomeric thin filament protein, troponin I, in cardiac muscle activation and its modulation by covalent modifications, sarcomere length, and intracellular pH. This evidence demonstrates that the cardiac variant of troponin I (cTnl), which is the only isoform expressed in the adult myocardium, has unique structure and function that are specialized for extrinsic and intrinsic control of cardiac contraction and relaxation.

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Solaro, R.J. (2003). The Special Structure and Function of Troponin I in Regulation of Cardiac Contraction and Relaxation. In: Sugi, H. (eds) Molecular and Cellular Aspects of Muscle Contraction. Advances in Experimental Medicine and Biology, vol 538. Springer, Boston, MA. https://doi.org/10.1007/978-1-4419-9029-7_36

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