Tubby protein homolog is a protein that in humans is encoded by the TUB gene. This gene encodes a member of the Tubby family of bipartite transcription factors. The encoded protein may play a role in obesity and sensorineural degradation. The crystal structure has been determined for a similar protein in mouse, and it functions as a membrane-bound transcription regulator that translocates to the nucleus in response to phosphoinositide hydrolysis. Two transcript variants encoding distinct isoforms have been identified for this gene.