Disease relevance of TXN

• Thus, TRX may be specifically induced by acute inflammatory stimuli, and the development of acute immune-mediated myocarditis may be regulated by the cellular redox state via TRX [1].
• Reductive cleavage of tetanus toxin and botulinum neurotoxin A by the thioredoxin system from brain. Evidence for two redox isomers of tetanus toxin [2].

High impact information on TXN

• Some aspects of the proposed model may be relevant to all forms of FBPase, including the thioredoxin-regulated FBPase from the chloroplast [3].
• Enzyme regulation in C4 photosynthesis. Purification and properties of thioredoxin-linked fructose bisphosphatase and sedoheptulose bisphosphatase from corn leaves [4].
• Under mild H(2)O(2) stress, a slow and transient activation of TTase, Trx, and TR was observed [5].
• Induction of thioltransferase and thioredoxin/thioredoxin reductase systems in cultured porcine lenses under oxidative stress [5].
• Nitric oxide-induced inhibition of lung endothelial cell nitric oxide synthase via interaction with allosteric thiols: role of thioredoxin in regulation of catalytic activity [6].

Chemical compound and disease context of TXN

• Temocapril treatment ameliorates autoimmune myocarditis associated with enhanced cardiomyocyte thioredoxin expression [7].

Biological context of TXN

• The eucaryotic enzymes, which are light activated by the thioredoxin/ferredoxin system (Buchanan, 1980), were each shown to contain a putative regulatory amino acid sequence (Marcus et al., 1988; Porter et al., 1988) [8].
• Upregulation of thioredoxin (TRX) expression in giant cell myocarditis in rats [1].

Anatomical context of TXN

• The pyruvate and alpha-ketoglutarate dehydrogenase complexes isolated from pig heart mitochondria promote the reduction of thioredoxin in the presence of their alpha-ketoacid substrates, coenzyme A, and free lipoate [9].
• Thioredoxin was prominently localized in the folliculo-stellatae cells of the adenohypophysis while only a minor proportion of the glandular cells were positive [10].
• In the neurohypophysis, thioredoxin immunoreactivity was very intense in the pituicytes and moderate in the clusters of synaptic terminals [10].
• A role of both proteins in secretory processes has been suggested and recently it has been demonstrated that thioredoxin functions as a growth factor for lymphocytes in cell cultures [10].
• An immunohistochemical study showed that TRX stain was enhanced in infiltrating inflammatory cells and in damaged myocytes [7].

Associations of TXN with chemical compounds

• Thioredoxin-regulated reversal of NO-induced modulation of NO synthase protein suggests that an oxidative conformational change in vicinal thiols, resulting in the formation of intramolecular or intermolecular disulfides or both, is involved [6].
• Substrate-specific generation of reduced thioredoxin was established by two independent methods, viz. reduction of insulin and thioredoxin reductase-catalyzed NADPH formation [9].
• Western blot showed that temocapril enhanced cytosolic redox regulatory protein TRX expression, but neither mitochondrial TRX2 nor antioxidant enzymes, such as copper-zinc superoxide dismutase (Cu/Zn-SOD) or manganese superoxide dismutase (Mn-SOD) expression, was increased by the preconditioning treatment [7].
• NO-induced loss of the catalytic activity of PKC-zeta was restored by incubation with the disulfide reducing agent dithiothreitol (DTT) as well as by purified thioredoxin or thioredoxin reductase [11].

Other interactions of TXN

• Similarly, enzymatic reduction by thioredoxin/thioredoxin reductase, but not by glutaredoxin, reversed the inhibition of membrane fraction and purified NO synthase isolated from diamide-treated cells [12].
• Finally, the location of cysteines residues provides a basis for a preliminary discussion of the activation of the enzyme by reduction of cysteines via the ferredoxin-thioredoxin f system; this process is complementary to activation by pH changes, Mg2+ or Ca2+, Fru-1,6-P2, and possibly Fru-2,6-P2 [13].
• An engineered pepsinogen, which was a fusion protein of thioredoxin and pepsinogen, exhibited dominant self-activation (unimolecular reaction; intramolecular activation) in contrast to recombinant pepsinogen which exhibited both unimolecular and bimolecular reactions (intermolecular activation mediated by pepsin released during activation) [14].
• Confocal imaging studies revealed co-localization of PKC and thioredoxin in PAEC [11].
• Regarding the biological functions of glutaredoxin and thioredoxin, these results show that involvement in the processing of secretory proteins is not a general property of these two thiol-disulfide oxidoreductases, not even specifically in the case of cysteine-rich secretory proteins [15].

Analytical, diagnostic and therapeutic context of TXN

• To examine the possible involvement of a redox regulating mechanism in the pathogenesis of immune-mediated myocarditis, myocarditis was induced by immunization of porcine cardiac myosin in rats and immunohistochemistry and Western blot for thioredoxin (TRX) were performed [1].

References