Enables p53 binding activity and ubiquitin protein ligase activity. Involved in apoptotic process and positive regulation of muscle cell differentiation. Acts upstream of or within several processes, including blood vessel remodeling; circulatory system development; and traversing start control point of mitotic cell cycle. Located in cytoplasm and nucleolus. Is expressed in several structures, including alimentary system; embryo ectoderm; genitourinary system; respiratory system; and sensory organ. Human ortholog(s) of this gene implicated in chronic myeloid leukemia; endocrine gland cancer (multiple); glioblastoma; ichthyosis; and sarcoma. Orthologous to human MDM2 (MDM2 proto-oncogene). [provided by Alliance of Genome Resources, Apr 2022]