Protein Domain : Transglutaminase, N-terminal IPR001102

Type	Domain
Description	Synonym(s): Protein-glutamine gamma-glutamyltransferase, Fibrinoligase, TGase. Protein-glutamine gamma-glutamyltransferases ( ) (TGase) are calcium-dependent enzymes that catalyse the cross-linking of proteins by promoting the formation of isopeptide bonds between the γ-carboxyl group of a glutamine in one polypeptide chain and the ε-amino group of a lysine in a second polypeptide chain. TGases also catalyse the conjugation of polyamines to proteins [ , ].Transglutaminases are widely distributed in various organs, tissues and body fluids. The best known transglutaminase is blood coagulation factor XIII, a plasma tetrameric protein composed of two catalytic A subunits and two non-catalytic B subunits. Factor XIII is responsible for cross-linking fibrin chains, thus stabilising the fibrin clot.There are commonly three domains: N-terminal, middle ( ) and C-terminal ( ). This entry represents the N-terminal domain found in transglutaminases. Proteins containing this domain also include Protein 4.2 (also known as Epb42), which is one of the most abundant protein components of the erythrocyte membrane. The protein shares significant sequence homology with transglutaminases, but lacks the catalytic triad residues required for transglutaminase activity [ ]. The complete or nearly complete absence of protein 4.2 is associated with an atypical form of hereditary spherocytosis (HS) [].
Short Name	Transglutaminase_N