Biological Functionalities of Transglutaminase 2 and the Possibility of Its Compensation by Other Members of the Transglutaminase Family

Table 2

Transglutaminase 2 substrates, reactive sites, cellular localizations, and possible involvement in human physiology/diseases.

TG2 substrate	Reactive site	Localization	Physiology/disease
Acetylcholine esterase	Glutamine	Intracellular	Neurological disease [53]
Actin	Glutamine and lysine	Intracellular	Cytoskeleton regulation [124]
Aldolase	Reactive glutamine present but specific residue is unknown	Intracellular	Genetic disease, endocrine and metabolic diseases, autoimmune and inflammatory diseases [125]
Androgen receptor		Intracellular (nuclear receptor)	Endocrine and metabolic diseases [97, 98]
Annexin I (lipocortin I)	Glutamine	Intracellular	Autoimmune and inflammatory diseases, cytoskeleton regulation [126]
Calgizzarin-S100C protein-MLN 70—S100A11	Glutamine and lysine	Keratinocyte cornified envelope	Endocrine and metabolic diseases, dermatological diseases [127]
Collagen alpha 1(III)	Glutamine	Extracellular	Extracellular matrix interaction and stabilization, autoimmune and inflammatory diseases [128]
α-B-crystallin	Lysine	Intracellular	Cell life and death, cytoskeleton regulation, protein stabilization [129]
β-A3 crystallin	Glutamine	Intracellular	Cell life and death, cytoskeleton regulation, protein stabilization [130]
β-B3 crystallin	Glutamine	Intracellular	Cell life and death, cytoskeleton regulation, protein stabilization [131]
β-Bp (beta-B2) crystalline	Glutamine	Intracellular	Cell life and death, cytoskeleton regulation, protein stabilization [131]
Cytochrome c	Glutamine	Intracellular	Cell life and death [132]
Fibronectin	Glutamine	Extracellular	Protein stabilization, extracellular matrix interaction and stabilization [68]
Fibrinogen A alpha	Glutamine and lysine	Extracellular	Extracellular matrix interaction and stabilization, autoimmune and inflammatory diseases [133]
Glutathione S-transferase	Glutamine, lysine, and fluorescein	Intracellular	Extracellular matrix interaction and stabilization [134]
Gluten proteins	Glutamine	Extracellular	Celiac disease [79]
Glyceraldehyde 3 phosphate dehydrogenase	Lysine	Intracellular	Neurological diseases [135]
H3 histone	Glutamine	Intracellular	Cell life and death [136]
H4 histone	Glutamine	Intracellular	Cell life and death [136]
H2A histone	Glutamine	Intracellular	Cell life and death [136]
H2B histone	Glutamine	Intracellular	Cell life and death [136]
Importin alpha 3		Nuclear transport protein	Cell life and death [34]
α-Ketoglutarate dehydrogenase	Lysine	Intracellular	endocrine and metabolic diseases [137]
Latent TGF-beta binding protein-1 (LTBP-1)		Extracellular	Carcinogenesis, autoimmune, and inflammatory diseases [138]
α-2-Macroglobulin receptor-associated protein	Glutamine	Extracellular	autoimmune and inflammatory diseases [139]
Microtubule-associated protein tau-isoform Tau-F (Tau-4)	Glutamine and lysine	Intracellular	Cytoskeleton regulation, neurological diseases [140]
Myosin		Intracellular	Cytoskeleton regulation [141]
Nidogen	Glutamine	Extracellular	Extracellular matrix interaction and stabilization [142]
Osteocalcin		Extracellular	Autoimmune and inflammatory diseases [143]
Osteonectin	Glutamine	Extracellular	Autoimmune and inflammatory diseases, extracellular matrix interaction, and stabilization [144]
Osteopontin	Glutamine	Extracellular	Autoimmune and inflammatory diseases, extracellular matrix interaction, and stabilization [145]
Phospholipase A2	Glutamine	Extracellular	Endocrine and metabolic diseases, signal transduction, autoimmune, and inflammatory diseases [2, 86]
Troponin T		Intracellular	Cytoskeleton regulation [146]