[The involvement of transglutaminase 2 in autoimmunological diseases].
Transglutaminase 2 (TG-ase 2) is one of the enzymes which catalyzes the deamination and transacylation of proteins. The transfer of a glutamine acyl residue to a lysine amine group of the acceptor protein is one of the posttranslational covalent modifications regulating some polypeptide activities. The control of protein oligomerization by TG-ase 2 is a cause of the formation of detergent-insoluble macromolecular aggregates. These inclusions are present in degenerating cells during, for example, Alzheimer's and Parkinson's disease. Overexpression of TG-ase 2 has been noted in apoptotic cells. Protein reserves in cereals are rich in glutamine, a substrate of TG-ase 2. Deamination of glutamine is the most important reaction for the initiation of the inflammatory process during gluten-dependent disease of the gut (celiac disease). Grains that contain gliadin are a cause of inflammatory reaction in children with intolerance to glutene. Interactions of the TG-ase product-glutamate with antigens of the major histocompatibility complex type II (MHC II, or HLA DQ) cause autoimmunological reaction by CD4+ T lymphocytes. Knowledge of the kinetic and molecular character of TG-ase 2 has contributed to finding peptides to replace gliadin. These molecules do not evoke immunological events.
Ostrowski
Maciej
M
Katedra i Zakład Histologii i Embriologii, Uniwersytetu Mikołaja Kopernika w Toruniu Collegium Medicum im. L. Rydygiera w Bydgoszczy, 85-092 Bydgoszcz. macost2@wp.pl
Izdebska
Magdalena
M
Grzanka
Alina
A
Zuryń
Agnieszka
A
Grzanka
Dariusz
D
D000818:Animals; D017209:Apoptosis / Q000276:immunology; D001327:Autoimmune Diseases / Q000201:enzymology*; D002446:Celiac Disease / Q000503:physiopathology; D004789:Enzyme Activation; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D007249:Inflammation / Q000503:physiopathology; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases / Q000378:metabolism*
D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D019204:GTP-Binding Proteins