Tissue transglutaminase (abbreviated as TG2 or tTG) is an enzyme (EC 2.3.2.13) of the transglutaminase family. Like other transglutaminases, it crosslinks proteins between an ε-amino group of a lysine residue and a γ-carboxamide group of glutamine residue, creating an inter- or intramolecular bond that is highly resistant to proteolysis (protein degradation). It is particularly notable for being the autoantigen in coeliac disease, but is also known to play a role in apoptosis, cellular differentiation and matrix stabilisation. Transglutaminases are enzymes that catalyze the crosslinking of proteins by epsilon-gamma glutamyl lysine isopeptide bonds. While the primary structure of transglutaminases is not conserved, they all have the same amino acid sequence at their active sites and their activity is calcium-dependent. The protein encoded by this gene acts as a monomer, is induced by retinoic acid, and appears to be involved in apoptosis. Finally, the encoded protein is the autoantigen implicated in celiac disease. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq].
Function: Catalyzes the cross-linking of proteins and the conjugation of polyamines to proteins.