Kinase Subfamily Kit

Kinase Classification: Group TK: Family PVR: Subfamily Kit

Kit is a vertebrate-specific subfamily of receptor tyrosine kinases, including the human genes kit, Flt3 and Fms/CSF1R, involved in blood cell development and various other functions.

Evolution

The three kit family members are found in all vertebrates, but not in any invertebrate. They likely arose as a tandem duplication of an ancestral PVR gene, which was then double-duplicated by the whole genome duplication at the base of the vertebrates. Duplicate kit and fms genes are found in fish.

Domain Structure

The extracellular region consists of 5 Immunoglobulin repeats, flanked by a signal peptide and a transmembrane region, while the intracellular region encodes a kinase domain and several other important short functional motifs.