Myosin - still a good reference for skeletal muscle fibre classification?

摘要

Myosin heavy chain (MHC) isoforms have been taken for the molecular signature of skeletal muscle fibres based on their relationship to mechanical properties -maximum shortening velocity, power -and ATP consumption. This relation between MHCs, fibre mechanics and energy suggests that they direct a concerted myofibre molecular and functional program. Switching MHC isoforms had been reported to change 'myofibre type', but finding two MHC isoforms expressed in a single myofibre made interpreting their influence on fibre contractile properties more complex and raised an intriguing question about their relation to intracellular Ca~(2+) homeostasis.