Head-head interaction characterizes the relaxed state of Limulus muscle myosin filaments.

ABSTRACT: Regulation of muscle contraction via the myosin filaments occurs in vertebrate smooth and many invertebrate striated muscles. Studies of unphosphorylated vertebrate smooth muscle myosin suggest that activity is switched off through an intramolecular interaction between the actin-binding region of one head and the converter and essential light chains of the other, inhibiting ATPase activity and actin interaction. The same interaction (and additional interaction with the tail) is seen in three-dimensional reconstructions of relaxed, native myosin filaments from tarantula striated muscle, suggesting that such interactions are likely to underlie the off-state of myosin across a wide spectrum of the animal kingdom. We have tested this hypothesis by carrying out cryo-electron microscopy and thre

SUBMITTER: Zhao FQ 

PROVIDER: S-EPMC4266557 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature