Myosin Regulatory Light Chain MRCL3 (11-24) MLCK Substrate

KKRPQRATSNVFAM-NH2 corresponds to residues 11-24 of human myosin regulatory light chain MRCL3 and is used as a peptide substrate for myosin light-chain kinase (MLCK). The sequence contains a serine phosphoacceptor within the native regulatory region of myosin light chain, providing a defined reagent for biochemical studies of MLCK catalytic activity and calcium/calmodulin-dependent phosphorylation.

• MLCK activity assays
• myosin light-chain phosphorylation studies
• Ca2+/calmodulin signaling research
• kinase inhibitor screening

This peptide models only a short segment of MRCL3. Catalytic behavior may differ from intact myosin regulatory light chain because higher-order protein structure and additional binding interactions are absent.

1. Activation of a cytosolic serine protein kinase by epidermal growth factor
2. Restoration of the calcium binding activity of mutant calmodulins toward normal by the presence of a calmodulin binding structure