Enables several functions, including ATPase binding activity; potassium channel regulator activity; and transmembrane transporter binding activity. Involved in several processes, including positive regulation of ion transmembrane transporter activity; regulation of cardiac muscle cell action potential; and regulation of heart contraction. Acts upstream of or within several processes, including cardiac muscle contraction; regulation of cardiac muscle cell membrane potential; and regulation of cation channel activity. Located in several cellular components, including T-tubule; intercalated disc; and myofibril. Is integral component of plasma membrane. Is active in paranodal junction. Is expressed in central nervous system; eye; genitourinary system; and heart. Used to study sinoatrial node disease. Human ortholog(s) of this gene implicated in ankyrin-B-related cardiac arrhythmia; atrial fibrillation; long QT syndrome; and sick sinus syndrome. Orthologous to human ANK2 (ankyrin 2). [provided by Alliance of Genome Resources, Apr 2022]