Effect of troponin C on the cooperativity in Ca2+ activation of cardiac muscle
Authors:
- 29 August 1988
- journal article
- Published by Wiley in FEBS Letters
- Vol. 236 (2) , 441-444
Abstract
This study describes the effects of exchanging native cardiac troponin C (CTnC) from the right ventricular muscle of Syrian hamster for purified skeletal (S) TnC from fast twitch muscles in triggering cardiac contraction. Ca2+ sensitivity of the myocardium became decreased with STnC to 62% of the original value with CTnC. Furthermore, the slope of the pCa‐force curve of cardiac muscle was found to be increased with STnC. The results show that the TnC moiety, as part of the switching mechanism during activation, also regulates thin‐filament cooperativity in muscle. Modifications in both the Ca2+ sensitivity and cooperativity are associated with alterations in the primary structure of TnC.Keywords
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