The protein may be important in cardiac antiarrhythmia via the strong suppression of voltage-gated L-type Ca2+ currents. As regulator of voltage-dependent L-type calcium channel subunit alpha-1C trafficking to the cell membrane. Inhibits cardiac hypertrophy through the calmodulin-dependent kinase II (CaMKII) pathway and phosphorylation and activation of CAMK2D. Mostly expressed in the heart and muscle of type II diabetic humans. Also found in the skeletal muscle, lung and adipose tissue. Lesser amounts in placenta and kidney.