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Structural and Functional Properties of Kappa Tropomyosin

In the myocardium, the TPM1 gene expresses two isoforms of tropomyosin (Tpm), alpha (αTpm; Tpm 1.1) and kappa (κTpm; Tpm 1.2). κTpm is the result of alternative splicing of the TPM1 gene. We studied the structural features of κTpm and its regulatory function in the atrial and ventricular myocardium...

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Autores principales: Kopylova, Galina V., Kochurova, Anastasia M., Yampolskaya, Daria S., Nefedova, Victoria V., Tsaturyan, Andrey K., Koubassova, Natalia A., Kleymenov, Sergey Y., Levitsky, Dmitrii I., Bershitsky, Sergey Y., Matyushenko, Alexander M., Shchepkin, Daniil V.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10179609/
https://www.ncbi.nlm.nih.gov/pubmed/37176047
http://dx.doi.org/10.3390/ijms24098340
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author Kopylova, Galina V.
Kochurova, Anastasia M.
Yampolskaya, Daria S.
Nefedova, Victoria V.
Tsaturyan, Andrey K.
Koubassova, Natalia A.
Kleymenov, Sergey Y.
Levitsky, Dmitrii I.
Bershitsky, Sergey Y.
Matyushenko, Alexander M.
Shchepkin, Daniil V.
author_facet Kopylova, Galina V.
Kochurova, Anastasia M.
Yampolskaya, Daria S.
Nefedova, Victoria V.
Tsaturyan, Andrey K.
Koubassova, Natalia A.
Kleymenov, Sergey Y.
Levitsky, Dmitrii I.
Bershitsky, Sergey Y.
Matyushenko, Alexander M.
Shchepkin, Daniil V.
author_sort Kopylova, Galina V.
collection PubMed
description In the myocardium, the TPM1 gene expresses two isoforms of tropomyosin (Tpm), alpha (αTpm; Tpm 1.1) and kappa (κTpm; Tpm 1.2). κTpm is the result of alternative splicing of the TPM1 gene. We studied the structural features of κTpm and its regulatory function in the atrial and ventricular myocardium using an in vitro motility assay. We tested the possibility of Tpm heterodimer formation from α- and κ-chains. Our result shows that the formation of ακTpm heterodimer is thermodynamically favorable, and in the myocardium, κTpm most likely exists as ακTpm heterodimer. Using circular dichroism, we compared the thermal unfolding of ααTpm, ακTpm, and κκTpm. κκTpm had the lowest stability, while the ακTpm was more stable than ααTpm. The differential scanning calorimetry results indicated that the thermal stability of the N-terminal part of κκTpm is much lower than that of ααTpm. The affinity of ααTpm and κκTpm to F-actin did not differ, and ακTpm interacted with F-actin significantly worse. The troponin T1 fragment enhanced the κκTpm and ακTpm affinity to F-actin. κκTpm differently affected the calcium regulation of the interaction of pig and rat ventricular myosin with the thin filament. With rat myosin, calcium sensitivity of thin filaments containing κκTpm was significantly lower than that with ααTpm and with pig myosin, and the sensitivity did not differ. Thin filaments containing κκTpm and ακTpm were better activated by pig atrial myosin than those containing ααTpm.
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spelling pubmed-101796092023-05-13 Structural and Functional Properties of Kappa Tropomyosin Kopylova, Galina V. Kochurova, Anastasia M. Yampolskaya, Daria S. Nefedova, Victoria V. Tsaturyan, Andrey K. Koubassova, Natalia A. Kleymenov, Sergey Y. Levitsky, Dmitrii I. Bershitsky, Sergey Y. Matyushenko, Alexander M. Shchepkin, Daniil V. Int J Mol Sci Article In the myocardium, the TPM1 gene expresses two isoforms of tropomyosin (Tpm), alpha (αTpm; Tpm 1.1) and kappa (κTpm; Tpm 1.2). κTpm is the result of alternative splicing of the TPM1 gene. We studied the structural features of κTpm and its regulatory function in the atrial and ventricular myocardium using an in vitro motility assay. We tested the possibility of Tpm heterodimer formation from α- and κ-chains. Our result shows that the formation of ακTpm heterodimer is thermodynamically favorable, and in the myocardium, κTpm most likely exists as ακTpm heterodimer. Using circular dichroism, we compared the thermal unfolding of ααTpm, ακTpm, and κκTpm. κκTpm had the lowest stability, while the ακTpm was more stable than ααTpm. The differential scanning calorimetry results indicated that the thermal stability of the N-terminal part of κκTpm is much lower than that of ααTpm. The affinity of ααTpm and κκTpm to F-actin did not differ, and ακTpm interacted with F-actin significantly worse. The troponin T1 fragment enhanced the κκTpm and ακTpm affinity to F-actin. κκTpm differently affected the calcium regulation of the interaction of pig and rat ventricular myosin with the thin filament. With rat myosin, calcium sensitivity of thin filaments containing κκTpm was significantly lower than that with ααTpm and with pig myosin, and the sensitivity did not differ. Thin filaments containing κκTpm and ακTpm were better activated by pig atrial myosin than those containing ααTpm. MDPI 2023-05-06 /pmc/articles/PMC10179609/ /pubmed/37176047 http://dx.doi.org/10.3390/ijms24098340 Text en © 2023 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Kopylova, Galina V.
Kochurova, Anastasia M.
Yampolskaya, Daria S.
Nefedova, Victoria V.
Tsaturyan, Andrey K.
Koubassova, Natalia A.
Kleymenov, Sergey Y.
Levitsky, Dmitrii I.
Bershitsky, Sergey Y.
Matyushenko, Alexander M.
Shchepkin, Daniil V.
Structural and Functional Properties of Kappa Tropomyosin
title Structural and Functional Properties of Kappa Tropomyosin
title_full Structural and Functional Properties of Kappa Tropomyosin
title_fullStr Structural and Functional Properties of Kappa Tropomyosin
title_full_unstemmed Structural and Functional Properties of Kappa Tropomyosin
title_short Structural and Functional Properties of Kappa Tropomyosin
title_sort structural and functional properties of kappa tropomyosin
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10179609/
https://www.ncbi.nlm.nih.gov/pubmed/37176047
http://dx.doi.org/10.3390/ijms24098340
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