Enables ATPase inhibitor activity and identical protein binding activity. Involved in several processes, including response to insulin; response to testosterone; and response to zinc ion. Located in sarcoplasmic reticulum and vesicle. Part of protein-containing complex. Used to study congestive heart failure; heart disease; and myocardial infarction. Biomarker of type 2 diabetes mellitus. Human ortholog(s) of this gene implicated in dilated cardiomyopathy 1P and hypertrophic cardiomyopathy 18. Orthologous to human PLN (phospholamban). [provided by Alliance of Genome Resources, Apr 2022]