Predicted to enable cysteine-type endopeptidase inhibitor activity involved in apoptotic process; protease binding activity; and serine-type endopeptidase inhibitor activity. Acts upstream of or within T cell mediated cytotoxicity. Predicted to be located in Golgi apparatus; cytosol; and nucleoplasm. Predicted to be active in cytoplasm and extracellular space. Is expressed in atrioventricular canal; atrioventricular valve; endocardial cushion; interventricular septum; and mitral valve. Orthologous to human SERPINB9 (serpin family B member 9). [provided by Alliance of Genome Resources, Apr 2022]