Resumo

PADRON, Raúl. El mecanismo molecular de la regulación de la contracción muscular. AVFT [online]. 2008, vol.27, n.1, pp.2-4. ISSN 0798-0264.

The structure of the thick filaments of striated muscle has been finally understood at the molecular level. The structure reveals intra- and inter-molecular interactions that held the myosin heads forming helices on the thick filament surface. The phosphorylation of the myosin regulatory light chains induces the weakening of these interactions, allowing the activation of thick filaments, and enabling their interaction with the thin filaments. These results open the possibility to the understanding of the molecular mechanism of the myosinlinked regulation of muscle contraction. This is of relevance as the mutations associated with mid ventricular cardiomyopathy are located near the phosphorylation site in the regulatory light chain.

Palavras-chave : muscle; myosin; regulation; activation; thick filament; three-dimensional reconstruction; cryo-electron microscopy; regulatory light chain; phosphorylation.