Disease relevance of TGM1

• Hepatitis B surface antigen binds to human serum albumin cross-linked by transglutaminase [1].
• The transglutaminase-mediated crosslinking of alpha B-crystallin may have implications for its involvement in normal and pathological processes in lens and other tissues [2].
• The results provide a basis for the suggestion that binding of a peptide to a protein, in connection to its modification to a T cell epitope, might be a general explanation for the role of TG2 in celiac disease and a possible mechanism for the generation of autoantigens [3].

Psychiatry related information on TGM1

• Here, we present a potential mechanism for the abnormal aggregation of tau in Alzheimer's disease: the covalent cross-linking of tau by the enzyme transglutaminase [4].

High impact information on TGM1

• Requirement for transglutaminase in the activation of latent transforming growth factor-beta in bovine endothelial cells [5].
• A hitherto unknown function for transglutaminase (TGase; R-glutaminyl-peptide: amine gamma-glutamyltransferase, EC 2.3.2.13) was found in the conversion of latent transforming growth factor-beta (LTGF-beta) to active TGF-beta by bovine aortic endothelial cells (BAECs) [5].
• Of particular interest is that antibody TGM-1, unlike TGM-3, bound poorly to homogenates of 19-d embryonic smooth muscles [6].
• Isolation of transglutaminase-reactive sequences from complex biological systems: a prominent lysine donor sequence in bovine lens [7].
• Apart from its fluorescent properties, the dansyl hapten offered special advantages as a "handle" for the rapid isolation of transglutaminase targets even in the complex system of lens cortical homogenate [7].

Biological context of TGM1

• A thrombin-independent TG in vascular cells of blood vessels could provide an alternate pathway to inhibit fibrinolysis and promote fibrin stabilization [8].
• These data indicate that HBsAg particles contain specific binding sites for transglutaminase-cross-linked human serum albumin, but it remains to be determined whether the albumin polymers play a role in the attachment of hepatitis B virus to hepatocytes [1].
• High calcium concentrations only stimulate transglutaminase activity after the cells become committed to terminal cell division [9].
• Our results show that the increase in transglutaminase activity correlates with the induction of the terminal differentiated phenotype and suggest that this enzyme can function as a marker for this program of differentiation of rabbit tracheal epithelial cells in culture [9].
• The surrounding amino acid sequence (Leu-Gly-Gln-Ser) shows homology with some synthetic peptide substrates of transglutaminase [10].

Anatomical context of TGM1

• Using [3H]methylamine as a convenient probe for transglutaminase activity, we have explored the action of this enzyme in the bovine eye lens [11].
• It was, moreover, established that several components of the lens cytoskeleton are substrates for transglutaminase [11].
• Sequencing of the cloned gene failed to reveal a secretory signal, which supports the notion that the thyroid transglutaminase is the cytosolic type [12].
• We postulate the intracellular assembly of Mr = 36,000 substrate, with subsequent cross-linking by transglutaminase and insolubilization into the keratinocyte membrane [13].
• Characterization of transglutaminase activity in rabbit tracheal epithelial cells. Regulation by retinoids [9].

Associations of TGM1 with chemical compounds

• We could characterize the glutamine residues acting as acyl-donor sites in three beta-crystallin chains, which are the only substrates for lens transglutaminase among the various lens-specific structural proteins, the crystallins [11].
• Since glutaraldehyde-dependent cross-linking of albumin molecules is not likely to occur in vivo, we considered the possibility that albumin may be polymerized by the action of transglutaminase enzymes present in plasma as activated factor XIII or released into plasma from tissues [1].
• Guinea pig liver transglutaminase covalently cross-linked human serum albumin molecules into dimers, trimers and polymers up to hexamers as shown by polyacrylamide gel electrophoresis in sodium dodecyl sulfate [1].
• GTP also inhibited rat liver and adult bovine aortic endothelial cell transglutaminase, but did not inhibit Factor XIIIa activity [14].
• Guanosine 5'-triphosphate (GTP) was found to inhibit guinea pig liver transglutaminase activity as measured by [3H]putrescine incorporation into casein [14].

Physical interactions of TGM1

• Stabilization of follicle-stimulating hormone-receptor complexes may involve calcium-dependent transglutaminase activation [15].

Other interactions of TGM1

• Microfibril-associated glycoprotein binds to the carboxyl-terminal domain of tropoelastin and is a substrate for transglutaminase [16].
• Fine mapping of the modification sites through mutational analysis demonstrated that Gln20 is a major amine acceptor site for the transglutaminase reaction and confirmed that a canonical tyrosine sulfation consensus sequence is the site of MAGP-1 sulfation [17].
• Covalent cross-linking of secreted bovine thyroglobulin by transglutaminase [12].
• HMW-DS is precipitable from endothelial cell monolayer extracts with antibodies against fibronectin, a known transglutaminase substrate [18].
• We propose that the Trappin protein family forms a new group of enzyme inhibitors with various specificities of the WAP domain, which share transglutaminase substrate motifs that can act as an anchoring sequence [19].

Analytical, diagnostic and therapeutic context of TGM1

• Antibody TGM-1 bound to a 50-kD peptide of subfragment-1 (S-1) previously found to be associated with actin binding and was localized by immunoelectron microscopy to the distal aspect of the myosin head [6].
• The dansylated peptide was incorporated into bovine lens proteins under the influence of the Ca(2+)-activated intrinsic transglutaminase and, after digestion by endoproteinase Glu-C, the tracer-containing fragments were isolated by affinity chromatography on an anti-dansyl antibody column [7].
• Only one messenger RNA for transglutaminase was found by Northern blotting [12].
• Soluble TG was shown to be a substrate for transglutaminase in vitro; moreover, the presence of transglutaminase was demonstrated by immunofluorescence and by immunoblotting in freshly isolated bovine thyroid globules [12].
• Circular dichroism analysis of monomeric and polymeric osteopontin indicated that transglutaminase treatment induces a conformational change in osteopontin, probably exposing motives relevant to its interactions with other extracellular molecules [20].

References