MYL2 and chronic obstructive pulmonary disease: Myosin light chain 2 (MLC2) is a diagnostic marker in COPD, and its phosphorylation plays key roles in the activation of actin and myosin motor to provide the contractility for several cellular processes in smooth muscle cells, such as cell contraction, stress fiber formation, cell motility, and cytokinesis (Duan et al., 2016).