Predicted to enable sodium channel regulator activity and transmembrane transporter binding activity. Predicted to be involved in cardiac conduction; cardiac muscle cell action potential; and regulation of ventricular cardiac muscle cell membrane repolarization. Predicted to act upstream of or within monoatomic ion transmembrane transport. Predicted to be located in membrane. Predicted to be part of voltage-gated sodium channel complex. Predicted to be active in plasma membrane. Is expressed in cardiac ventricle; liver; nervous system; and solid lens vesicle. Human ortholog(s) of this gene implicated in long QT syndrome 10. Orthologous to human SCN4B (sodium voltage-gated channel beta subunit 4).