Protein-glutamine gamma-glutamyltransferase 2 (TGM2) is a 78-kDa, calcium dependent enzyme,It belongs to the transglutaminase superfamily and transglutaminase family. The protein encoded by this TGM2 gene acts as a monomer, is induced by retinoic acid, and appears to be involved in apoptosis. TGM2 is the autoantigen implicated in celiac disease. Two transcript variants encoding different isoforms have been found for this gene.