Genes of the MAGE family direct the expression of tumor antigens that are recognized on a human melanoma by
autologous cytolytic T lymphocytes. The MAGE genes were initially isolated from different kinds of tumors, and based
on their virtually exclusive tumor-specific expression in adult tissues, they have
been used as targets for cancer immunotherapy. However, although a large number
of MAGE genes have now been identified and extensively studied in tumors of
various origin, their functions in normal cells remain unknown.
NCBI Summary:
This gene is a member of the MAGEB gene family. The members of this family have their entire coding sequences located in the last exon, and the encoded proteins show 50 to 68% sequence identity to each other. The promoters and first exons of the MAGEB genes show considerable variability, suggesting that the existence of this gene family enables the same function to be expressed under different transcriptional controls. The MAGEB genes are clustered on chromosome Xp22-p21. This gene sequence ends in the first intron of MAGEB1, another family member. This gene is expressed in testis.
General function
Receptor
Comment
Cellular localization
Cytoplasmic, Plasma membrane
Comment
Ovarian function
Oogenesis
Comment
Expression regulated by
Comment
Ovarian localization
Oocyte
Comment
Osterlund C, et al 2000 reported that Mage-b4, a novel melanoma antigen (MAGE) gene is specifically
expressed during germ cell differentiation.
They described
the isolation and characterization of a novel murine MAGE homologue, Mage-b4.
mRNA expression studies in a wide variety of adult and embryonic tissues
revealed that Mage-b4 is specifically expressed in fetal and adult gonads. An
antibody specific to Mage-b4 was developed, and using this antibody, the Mage-b4 protein was confined to the cytoplasm of germ cells.
Double-labeling experiments using antibodies against the meiosis-specific SCP3
protein and the Mage-b4 protein showed that Mage-b4 is down-regulated as the
germ cells enter meiosis in adult testis. In contrast, Mage-b4 was expressed in
female germ cells throughout meiosis, and the protein was also found in dormant
primary oocytes.