History and Biology of Transglutaminase 2: A Synopsis

Transglutaminase 2 (TG2) belongs to the family of transglutaminase, a large group of intracellular and extracellular enzymes that primarily catalyze the Ca2+-dependent post-translational modification of proteins. Discovery of the first transglutaminase in the early 1920s, has subsequently lead to the identification of nine members of the enzyme family including TG2; the most abundant, most popular and most studied member of the transglutaminase enzyme family. The popularity of TG2 is due to its uniqueness amongst other members of the Transglutaminase (Tgase) family. Its difference from other Tgase family members is due to its specialized structural and biochemical activities; abundant tissue distribution and sub-cellular localization; and multi-functionality and physiology. The growing interests in TG2 and related research has resulted to an attendant mega-research output; and the need to produce a well-structured compilation of data on this popular enzyme has arisen. It is against this background, that we have compiled herein, a synopsis of available literature on TG2 history, structural and biochemical activities, tissue distribution, and physiology. This was done with the view to providing a compendium of background information that could be handy to researchers and new interest in the field of TG2 research.