Study of regulatory effect of tropomyosin on actin-myosin interaction in skeletal muscle by in vitro motility assay

Biochemistry (Mosc). 2013 Mar;78(3):260-6. doi: 10.1134/S0006297913030073.

Abstract

The interaction between myosin and actin in striated muscle tissue is regulated by Ca2+ via thin filament regulatory proteins. Skeletal muscle possesses a whole pattern of myosin and tropomyosin isoforms. The regulatory effect of tropomyosin on actin-myosin interaction was investigated by measuring the sliding velocity of both actin and actin-tropomyosin filaments over fast and slow skeletal myosins using the in vitro motility assay. The actin-tropomyosin filaments were reconstructed with tropomyosin isoforms from striated muscle tissue. It was found that tropomyosins with different content of α-, β-, and γ-chains added to actin filaments affect the sliding velocity of filaments in different ways. On the other hand, the sliding velocity of filaments with the same content of α-, β-, and γ-chains depends on myosin isoforms of striated muscle. The reciprocal effects of myosin and tropomyosin on actin-myosin interaction in striated muscle may play a significant role in maintenance of effective work of striated muscle both during ontogenesis and under pathological conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / chemistry
  • Actins / metabolism*
  • Animals
  • Cattle
  • Muscle, Skeletal / chemistry
  • Muscle, Skeletal / metabolism*
  • Myosins / chemistry
  • Myosins / metabolism*
  • Protein Binding
  • Protein Isoforms / metabolism
  • Rabbits
  • Tropomyosin / chemistry
  • Tropomyosin / metabolism*

Substances

  • Actins
  • Protein Isoforms
  • Tropomyosin
  • Myosins