Ring Finger Protein 40 (RNF40)

E3 ubiquitin-protein ligase BRE1B is an enzyme contains a RING finger, a motif known to be involved in protein-protein and protein-DNA interactions. This protein was reported to interact with the tumor suppressor protein RB1. Studies of the rat counterpart suggested that this protein may function as an E3 ubiquitin-protein ligase, and facilitate the ubiquitination and degradation of syntaxin 1, which is an essential component of the neurotransmitter release machinery.The human RNF40 protein contains 1,001 amino acids and shares about 93% amino acid identity with the rat protein. Both proteins have 6 coiled-coil domains and a C-terminal RING finger motif. Ubiquitously expressed. Expressed at higher level in testis, heart and pancreas, while it is only weakly expressed in lung, skeletal muscle and small intestine.