Acts upstream of or within midbrain-hindbrain boundary morphogenesis. Is expressed in several structures, including mesoderm; midbrain neural keel; nervous system; neural tube; and trigeminal placode. Human ortholog(s) of this gene implicated in catecholaminergic polymorphic ventricular tachycardia 4 and long QT syndrome 14. Orthologous to human CALM1 (calmodulin 1).