Mafa
Developmental stage
In the developing pancreas, expressed exclusively in the insulin-positive cells from 13.5 dpc onward and never in the glucagon-expressing cells (at protein level) (PubMed:14973194). At 12.5dpc, at the mRNA level, detected in each formed somite, in myotomal cells. Also detected in the head neural tube, liver cells and, at low levels, in some mesenchyme-like cells (PubMed:14680841).
Function
Transcriptional factor that activates insulin gene expression (PubMed:12368292, PubMed:15665000). Acts synergistically with NEUROD1/BETA2 and PDX1 (PubMed:15665000). Binds the insulin enhancer C1/RIPE3b element (PubMed:12917329, PubMed:14680841, PubMed:14973194, PubMed:15665000). Binds to consensus TRE-type MARE 5'-TGCTGACTCAGCA-3' DNA sequence (By similarity).
Post-translational modifications
Ubiquitinated, leading to its degradation by the proteasome.
Phosphorylated at tyrosines.
Sequence Similarities
Belongs to the bZIP family. Maf subfamily.
Tissue Specificity
Expressed in brain, lung, spleen, pancreas and kidney (PubMed:12368292, PubMed:14680841). In the pancreas, expressed in the insulin-producing beta-cells of the islets of Langerhans (at protein level) (PubMed:12917329, PubMed:15923615). Also expressed in the eye (PubMed:12368292, PubMed:15923615).
Cellular localization
- Nucleus
Alternative names
Transcription factor MafA, Pancreatic beta-cell-specific transcriptional activator, V-maf musculoaponeurotic fibrosarcoma oncogene homolog A, Mafa