Enables MDM2/MDM4 family protein binding activity; enzyme inhibitor activity; and protein N-terminus binding activity. Involved in several processes, including negative regulation of lymphocyte proliferation; positive regulation of apoptotic process; and regulation of transcription, DNA-templated. Acts upstream of or within several processes, including negative regulation of cellular protein metabolic process; negative regulation of mammary gland epithelial cell proliferation; and positive regulation of apoptotic process involved in mammary gland involution. Located in cytoplasm and granular component. Part of protein-containing complex. Is expressed in several structures, including bone marrow; central nervous system; dorsal root ganglion; eye; and testis. Human ortholog(s) of this gene implicated in several diseases, including breast cancer (multiple); carcinoma (multiple); hematologic cancer (multiple); melanoma (multiple); and nervous system cancer (multiple). Orthologous to human CDKN2A (cyclin dependent kinase inhibitor 2A). [provided by Alliance of Genome Resources, Apr 2022]