Melanoma Inhibitory Activity Protein 2 (MIA2)

The deduced 541-amino acid protein contains an N-terminal signal sequence that is removed to form a mature 522-amino acid protein. In addition to the signal sequence, MIA2 contains an N-terminal SH3 domain and 2 intramolecular disulfide bonds. MIA2 shares 34 to 45% amino acid identity with MIA, OTOR, and TANGO (ARNT). RT-PCR detected highest expression in human and mouse liver and much weaker expression in testis. RT-PCR of parenchymal and nonparenchymal liver cells and tumor cell lines detected expression in a hepatoma cell line and in primary hepatocytes, but not in Kupffer cells, quiescent or activated hepatic stellate cells, or several nonhepatic tumor cell lines. In situ hybridization of mouse embryos detected expression of Mia2 restricted to the developing liver.