The Effect of Experimental Hyperthyroidism on Characteristics of Actin–Myosin Interaction in Fast and Slow Skeletal Muscles

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G. V. Kopylova^1,a*, D. V. Shchepkin¹, and S. Y. Bershitsky¹

¹Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, 620049 Yekaterinburg, Russia

^* To whom correspondence should be addressed.

Received September 19, 2017; Revision received January 29, 2018

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The molecular mechanism of the failure of contractile function of skeletal muscles caused by oxidative damage to myosin in hyperthyroidism is not fully understood. Using an in vitro motility assay, we studied the effect of myosin damage caused by oxidative stress in experimental hyperthyroidism on the actin–myosin interaction and its regulation by calcium. We found that hyperthyroidism-induced oxidation of myosin is accompanied by a decrease in the sliding velocity of the regulated thin filaments in the in vitro motility assay, and this effect is increased with the duration of the pathological process.

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KEY WORDS: actin–myosin interaction, calcium regulation, myosin carbonylation, in vitro motility assay

DOI: 10.1134/S000629791805005X

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