V maf musculoaponeurotic fibrosarcoma oncogene homolog B (avian)
V-maf musculoaponeurotic fibrosarcoma oncogene homolog B
Acts as a transcriptional activator or repressor. Plays a pivotal role in regulating lineage-specific hematopoiesis by repressing ETS1-mediated transcription of erythroid-specific genes in myeloid cells. Required for monocytic, macrophage, podocyte and islet beta cell differentiation. Involved in renal tubule survival and F4/80 maturation. Activates the insulin and glucagon promoters. Together with PAX6, transactivates weakly the glucagon gene promoter through the G1 element. SUMO modification controls its transcriptional activity and ability to specify macrophage fate. Binds element G1 on the glucagon promoter (By similarity). Involved either as an oncogene or as a tumor suppressor, depending on the cell context.
Involvement in disease
Defects in MAFB are the cause of multicentric carpotarsal osteolysis syndrome (MCTO) [MIM:166300]. MCTO is a rare skeletal disorder, usually presenting in early childhood with a clinical picture mimicking juvenile rheumatoid arthritis. Progressive destruction of the carpal and tarsal bone usually occurs and other bones may also be involved. Chronic renal failure is a frequent component of the syndrome. Mental retardation and minor facial anomalies have been noted in some patients.
Belongs to the bZIP family. Maf subfamily. Contains 1 bZIP domain.
The leucine-zipper domain is involved in the interaction with LRPICD.
Phosphorylated by GSK3 and MAPK13 on serine and threonine residues. Sumoylated. Sumoylation on Lys-32 and Lys-297 stimulates its transcriptional repression activity and promotes macrophage differentiation from myeloid progenitors.