Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1992 Jul 7;31(26):6126-33.
doi: 10.1021/bi00141a024.

Autophosphorylation of skeletal muscle myosin light chain kinase

Affiliations

Autophosphorylation of skeletal muscle myosin light chain kinase

Z H Gao et al. Biochemistry. .

Abstract

Ca2+/calmodulin-dependent myosin light chain kinase phosphorylates the regulatory light chain of myosin. Rabbit skeletal muscle myosin light chain kinase also catalyzes a Ca2+/calmodulin-dependent autophosphorylation with a rapid rate of incorporation of 1 mol of 32P/mol of kinase and a slower rate of incorporation up to 1.52 mol of 32P/mol. Autophosphorylation was inhibited by a peptide substrate that has a low Km value for myosin light chain kinase. Autophosphorylation at both rates was concentration-independent, indicating an intramolecular mechanism. There were no significant changes in catalytic properties toward light chain and MgATP substrates or in calmodulin activation properties upon autophosphorylation. After digestion with V8 protease, phosphopeptides were purified and sequenced. Two phosphorylation sites were identified, Ser 160 and Ser 234, with the former associated with the rapid rate of phosphorylation. Both sites are located amino terminal of the catalytic domain. These results indicate that the extended "tail" region of the enzyme can fold into the active site of the kinase.

PubMed Disclaimer

Similar articles

Cited by

Publication types

MeSH terms

LinkOut - more resources

-