Effect of hypothyroidism on actin subdomain-1 movement induced by myosin subfragment-1 binding in fast and slow rat skeletal muscles
The orientation and mobility of an N-(iodoacetyl)-(1-naphtyl-5-sulpho-ethylenediamine) fluorescent probe (1.5-IAEDANS) specifically bound to Cys-374 of actin in ghost muscle fibers isolated from fast and slow rat muscles were studied by polarized fluorimetry in the absence and presence of a myosin subfragment-1 (S1) in intact rats and in animals with a gradual (2–5 weeks) reduction in the level of thyroid hormones (development of hypothyroidism). The binding of S1 to F-actin of ghost muscle fibers was shown to induce changes in the orientation of dipoles of the 1.5-IAEDANS fluorescent probe and in the relative amount of the randomly oriented fluorophores that indicates changes in actin subdomain-1 orientation and mobility resulting from formation of its strong binding with S1. This effect is markedly inhibited by the development of hypothyroidism. The maximal effect of hypothyroidism is observed after 34 days of the development of the disease. It is suggested that the change in the thyroid status in muscle inhibits the ability of F-actin to form strong binding with myosin, which is essential for the generation of force.
Key wordsmuscle contraction hypothyroidism actin conformational changes F-actin polarized fluorescence
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- Borovikov Yu.S., Kirillina V.P., Chernogryadskaya N.A., and Braun A.D., Studies of Structural Changes in Muscle Fiber Contractile Proteins using Polarized Ultraviolet Fluorescence Microscopy. III. Structural Changes in the Contractile Apparatus of Muscle Fiber during Developing Necrosis, Tsitologiia, 1977, vol. 19, no. 4, pp. 382–387.Google Scholar
- Borovikov, Y.S., Dedova, I.V., Dos Remedios, C.G., Vikhoreva, N.N., Vikhorev, P.G., Avrova, S.V., Hazlett, T.L., and Van der Meer, B.W., Fluorescence Depolarization of Actin Filaments in Reconstructed Myofibers: the Effect of S1 or pPDM-S1 on Movements of Distinct Areas of Actin, Biophys. J., 2004, vol. 86, pp. 3020–3029.CrossRefPubMedGoogle Scholar
- Borovikov, Yu.S. and Gusev, E.B., Effect of Troponin-Tropomyosin Complex and Ca2+ on Conformational Changes in F-Actin Induced by Myosin Subfragmant 1, Fur. J. Biochem., 1983, vol. 136, pp. 363–369.Google Scholar
- Borovikov, Yu.S., Kirillina, V.P., and Chernogryadskaya, N.A., State of the Contractile Apparatus during the Development of a Pathological Process in the Muscles. V. Effect of Zenker’s Necrosis and Denervation Atrophy on FActin Structure, Tsitologiia, 1982, vol. 24, no. 8, pp. 918–923.Google Scholar
- Borovikov, Yu.S., Kirillina, V.P., Szczepanjwska, J., and Carraro, U., Polarized Microfluorimetry Investigation of the Conformational Changes of F-Actin in Ghost Fibers of Dast (EDL) and Slow (SOL) Rat Muscles Induced by Functional Electrostimulation, Basic and Applied Myology, 1991, vol. 1, pp. 139–143.Google Scholar
- Bremel, R.D. and Weber, A., Cooperation Within Actin Filaments in Vertebrate Skeletal Muscle, Nature, 1972, vol. 238, pp. 97–101.Google Scholar
- Ciechomska, I., Wojda, J., Jakubiec-Puka, A., and Kirillina, V., Effects of Some Hormones on the Skeletal Muscle Denervation Atrophy and on the Muscle Recovery Following Self-Reinnervation. I. Thymus factor X (TFX) and Ubiquitin, Int. J. of Thymol., 1998, vol. 6, pp. 493–501.Google Scholar
- Jajubiec-Puka, A., Catani, C., and Carraro, U., Myosin Heavy Chain Composition in Striated Muscle after Tenotomy, Biochem. J., 1992, vol. 282, pp. 237–242.Google Scholar
- Jakubiec-Puka, A., Wojda, J., Ciechimska, I., and Kirillina, V., The Effects of Hormones on the Skeletal Muscle Denervation Atrophy and on the Muscle Recovery Following Self-Reinnervation. II. Glucocorticoids, Int. J. Thymol., 1998, vol. 6, pp. 611–617.Google Scholar
- Kirillina, V.P. and Borovikov, Yu.S., Effect of Σ-ADP on the Structure of F-Actin-Myosin Subfragment-1 Complex, Basic Appl. Myology, 1992, vol. 2, pp. 169–174.Google Scholar
- Leijendekker, W.J. and Hardeveld, C. van, Phosphorilase a Formation, Myosinlight Chain Phosphorilation and the Energy Turnover in Contracting Skeletal Muscle of Thypothyroid Rats, J. Muscle Res. Cell Motyl., 1985, vol. 6, pp. 91–94.Google Scholar