Myosin phosphorylation

Phosphorylation of Mammalian Myosin Light Chain Kinases

The phosphorylation of the calmodulin-dependent enzyme myosin light chain kinase, purified from bovine tracheal smooth muscle and human blood platelets, by the catalytic subunit of CAMP-dependent protein kinase and by cGMP-dependent protein kinase was investigated. When myosin light chain kinase which has calmodulin bound is phosphorylated by the catalytic subunit of CAMP-dependent protein kina...

Myosin light chain phosphorylation to the rescue.

A common cause of heart failure is hypertrophic cardiomyopathy (HCM) with a prevalence of at least 1 in 500 in adults (1); more recent data suggest that the prevalence of HCM may be as high as 1 in 200 (2). HCM is characterized by disorganized myocyte structure; formation of excess connective tissue (fibrosis); and, importantly, enlargement of cardiac myocytes that increases the ventricular wal...

Myosin II Light Chain Phosphorylation Regulates Membrane

Phosphorylation of myosin regulatory light chain controls myosin head conformation in cardiac muscle

The effect of phosphorylation on the conformation of the regulatory light chain (cRLC) region of myosin in ventricular trabeculae from rat heart was determined by polarized fluorescence from thiophosphorylated cRLCs labelled with bifunctional sulforhodamine (BSR). Less than 5% of cRLCs were endogenously phosphorylated in this preparation, and similarly low values of basal cRLC phosphorylation w...

Myosin light chain kinase and myosin phosphorylation effect frequency-dependent potentiation of skeletal muscle contraction.

Repetitive stimulation potentiates contractile tension of fast-twitch skeletal muscle. We examined the role of myosin regulatory light chain (RLC) phosphorylation in this physiological response by ablating Ca(2+)/calmodulin-dependent skeletal muscle myosin light chain kinase (MLCK) gene expression. Western blot and quantitative-PCR showed that MLCK is expressed predominantly in fast-twitch skel...