Tags

Type your tag names separated by a space and hit enter

Regulation of myosin heavy chain expression during rat skeletal muscle development in vitro.
Mol Biol Cell. 2001 May; 12(5):1499-508.MB

Abstract

Signals that determine fast- and slow-twitch phenotypes of skeletal muscle fibers are thought to stem from depolarization, with concomitant contraction and activation of calcium-dependent pathways. We examined the roles of contraction and activation of calcineurin (CN) in regulation of slow and fast myosin heavy chain (MHC) protein expression during muscle fiber formation in vitro. Myotubes formed from embryonic day 21 rat myoblasts contracted spontaneously, and approximately 10% expressed slow MHC after 12 d in culture, as seen by immunofluorescent staining. Transfection with a constitutively active form of calcineurin (CN*) increased slow MHC by 2.5-fold as determined by Western blot. This effect was attenuated 35% by treatment with tetrodotoxin and 90% by administration of the selective inhibitor of CN, cyclosporin A. Conversely, cyclosporin A alone increased fast MHC by twofold. Cotransfection with VIVIT, a peptide that selectively inhibits calcineurin-induced activation of the nuclear factor of activated T-cells, blocked the effect of CN* on slow MHC by 70% but had no effect on fast MHC. The results suggest that contractile activity-dependent expression of slow MHC is mediated largely through the CN-nuclear factor of activated T-cells pathway, whereas suppression of fast MHC expression may be independent of nuclear factor of activated T-cells.

Authors+Show Affiliations

Laboratory of Biochemical Genetics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892-4036, USA.No affiliation info available

Pub Type(s)

Journal Article

Language

eng

PubMed ID

11359938

Citation

Torgan, C E., and M P. Daniels. "Regulation of Myosin Heavy Chain Expression During Rat Skeletal Muscle Development in Vitro." Molecular Biology of the Cell, vol. 12, no. 5, 2001, pp. 1499-508.
Torgan CE, Daniels MP. Regulation of myosin heavy chain expression during rat skeletal muscle development in vitro. Mol Biol Cell. 2001;12(5):1499-508.
Torgan, C. E., & Daniels, M. P. (2001). Regulation of myosin heavy chain expression during rat skeletal muscle development in vitro. Molecular Biology of the Cell, 12(5), 1499-508.
Torgan CE, Daniels MP. Regulation of Myosin Heavy Chain Expression During Rat Skeletal Muscle Development in Vitro. Mol Biol Cell. 2001;12(5):1499-508. PubMed PMID: 11359938.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Regulation of myosin heavy chain expression during rat skeletal muscle development in vitro. AU - Torgan,C E, AU - Daniels,M P, PY - 2001/5/22/pubmed PY - 2001/9/14/medline PY - 2001/5/22/entrez SP - 1499 EP - 508 JF - Molecular biology of the cell JO - Mol Biol Cell VL - 12 IS - 5 N2 - Signals that determine fast- and slow-twitch phenotypes of skeletal muscle fibers are thought to stem from depolarization, with concomitant contraction and activation of calcium-dependent pathways. We examined the roles of contraction and activation of calcineurin (CN) in regulation of slow and fast myosin heavy chain (MHC) protein expression during muscle fiber formation in vitro. Myotubes formed from embryonic day 21 rat myoblasts contracted spontaneously, and approximately 10% expressed slow MHC after 12 d in culture, as seen by immunofluorescent staining. Transfection with a constitutively active form of calcineurin (CN*) increased slow MHC by 2.5-fold as determined by Western blot. This effect was attenuated 35% by treatment with tetrodotoxin and 90% by administration of the selective inhibitor of CN, cyclosporin A. Conversely, cyclosporin A alone increased fast MHC by twofold. Cotransfection with VIVIT, a peptide that selectively inhibits calcineurin-induced activation of the nuclear factor of activated T-cells, blocked the effect of CN* on slow MHC by 70% but had no effect on fast MHC. The results suggest that contractile activity-dependent expression of slow MHC is mediated largely through the CN-nuclear factor of activated T-cells pathway, whereas suppression of fast MHC expression may be independent of nuclear factor of activated T-cells. SN - 1059-1524 UR - https://www.unboundmedicine.com/medline/citation/11359938/Regulation_of_myosin_heavy_chain_expression_during_rat_skeletal_muscle_development_in_vitro_ L2 - https://www.molbiolcell.org/doi/10.1091/mbc.12.5.1499?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub=pubmed DB - PRIME DP - Unbound Medicine ER -