V-Maf Musculoaponeurotic Fibrosarcoma Oncogene Homolog A (MAFA)

MAFA is a transcription factor that binds RIPE3b, a conserved enhancer element that regulates pancreatic beta cell-specific expression of the insulin gene.

The deduced 352-amino acid protein contains an N-terminal activation domain rich in serine, proline, and threonine, followed by 2 glycine-rich regions separated by a histidine-rich region, and a C-terminal DNA-binding and dimerization domain containing a basic leucine zipper. Northern blot analysis detected Mafa in mouse and hamster insulinoma cells, in mouse thymus, and in mouse embryos at embryonic day 14, and there was evidence of alternative splicing. No expression was detected in other mouse tissues examined or in a glucagon-producing cell line.