MAGEA2 acts mainly as a regulator of the p53 pathway. It reduces p53 (TP53) transactivation by recruiting HDAC3 to p53 transcription sites, and it also represses p73 (TP73) activity. It is proposed to enhance the activity of RING-type zinc finger E3 ubiquitin-protein ligases, probably by recruiting or stabilising the Ubl-conjugating enzyme (E2) at the E3:substrate complex. In vitro, it enhances the ubiquitin ligase activity of TRIM28 and stimulates p53 ubiquitination by TRIM28, potentially with the E2 enzyme UBE2H. It also negatively regulates acetylation and sumoylation of PML and represses PML-induced p53 acetylation and activation. The protein localises to the nucleus, including PML bodies.

The MAGEA2 gene belongs to the MAGEA gene family, whose members encode proteins with 50 to 80% sequence identity to each other. The promoters and first exons of the MAGEA genes vary considerably. This suggests that the family allows the same function to be expressed under different transcriptional controls. The genes are clustered on the X chromosome. The MAGEA2 gene has two identical copies at different loci, which accounts for the MAGEA2A symbol, and its alternatively spliced transcript variants encode the same protein.

The protein name, melanoma-associated antigen 2, reflects its discovery as an antigen recognised on a melanoma by autologous cytolytic T-lymphocytes. HGNC previously listed the gene as melanoma antigen family A2. UniProt notes that the protein may play a role in embryonal development and in tumour transformation or progression, and that it promotes cell viability in melanoma cell lines in vitro. The MAGEA family as a whole has been implicated in some hereditary disorders, such as dyskeratosis congenita.