Predicted to enable actin filament binding activity and actin monomer binding activity. Predicted to be involved in cardiac muscle contraction; positive regulation of ATPase activity; and regulation of the force of heart contraction. Predicted to be located in A band. Predicted to be part of myosin complex. Is expressed in several structures, including alimentary system; brain; great vessel of heart; heart; and limb. Human ortholog(s) of this gene implicated in cardiomyopathy and familial atrial fibrillation. Orthologous to human MYL4 (myosin light chain 4). [provided by Alliance of Genome Resources, Apr 2022]