20 kDa myosin light chain,KMLC,LC20,MLC-2C,MLCK2,MRLC1,MYL9,MYL9,Myosin regulatory light chain 2,Myosin regulatory light chain 2,smooth muscle isoform,Myosin regulatory light chain 9,Myosin regulatory light chain MRLC1,Myosin regulatory light polypeptide 9,Myosin RLC,Myosin,light chain 9,regulatory,MYRL2,smooth muscle isoform,Myosin, a structural component of muscle, consists of two heavy chains and four light chains. The protein encoded by this gene is a myosin light chain that may regulate muscle contraction by modulating the ATPase activity of myosin heads. The encoded protein binds calcium and is activated by myosin light chain kinase. Two transcript variants encoding different isoforms have been found for this gene.