Overview:

Troponin1 is a member of the tropomyosin family and regulates the calcium sensitivity of the myofibril contractile apparatus of striated muscles. Troponin1 is part of a complex with troponin T and troponin C in which Troponin1 acts as an inhibitory subunit that blocks actin-myosin interactions and thereby mediates striated muscle relaxation (1). Troponin1 is expressed in cardiac and skeletal muscle during early development but is restricted to slow-twitch skeletal muscle fibers in adults. The Troponin1 protein prevents muscle contraction by inhibiting calcium-mediated conformational changes in actin-myosin complexes (2).

Gene Aliases:

TNNI1; DKFZp451O223; SSTNI; TNN1

Genbank Number:

NM_003281

References:

1. Tiso, N. et al: Fine mapping of five human skeletal muscle genes: alpha-tropomyosin, beta-tropomyosin, troponin-I slow-twitch, troponin-I fast-twitch, and troponin-C fast. Biochem. Biophys. Res. Commun. 230: 347-350, 1997. 2. Nadal-Ginard.et al: Molecular basis of cardiac performance: plasticity of the myocardium generated through protein isoform switches. J. Clin. Invest. 84: 1693-1700,198