The function of MYLK2 (myosin light chain kinase 2, ENSG00000101306) is as follows. Ca(2+)/calmodulin-dependent kinase that phosphorylates the regulatory light chain (RLC) of sarcomeric myosin in skeletal and cardiac muscle. Phosphorylation of RLC promotes displacement of myosin cross-bridges from the thick filament backbone toward actin-containing thin filaments, increasing the probability of cross-bridge entry into force-generating states and thereby potentiating contractile force at submaximal Ca(2+) concentrations. {ECO:0000250|UniProtKB:Q8VCR8, ECO:0000269|PubMed:11733062}.