Thioredoxin is a small redox protein that is widely expressed in most organisms. In humans, two isoforms of thioredoxin are encoded by the TXN gene. Thioredoxins are characterized by the presence of two neighboring cysteines arranged in a CXXC motif at the active site. Thioredoxin exists as a homodimer in the cytoplasm and participates in a variety of redox reactions through the reversible oxidation of a dithiol group at its active site to a disulfide.
Thioredoxins are maintained in the reduced state by the flavoenzyme thioredoxin reductase through an NADPH-dependent reaction. Thioredoxins act as electron donors to peroxidases and ribonucleotide reductase. They are responsible for the reversible S-nitrosylation of cysteine residues in target proteins, as part of the response to intracellular nitric oxide. Several transcription factors, such as c-Fos/c-Jun, NF-kappa B, and AP1 also require thioredoxin-mediated reduction to exert DNA-binding activity. Thioredoxin knockout mammal embryos die in utero. Numerous other functions for thioredoxin have been described, including oxidative stress protection and control of growth and apoptosis.
Alternate names for thioredoxin include surface-associated sulphydryl protein (SASP), ATL-derived factor (ADF), TRX, TRDX and TRX1.
ELISAs for Thioredoxin Detection
The Human Thioredoxin Assay (Cat. # 27417A) is a solid-phase sandwich ELISA that uses two highly specific antibodies to human thioredoxin protein; one antibody is precoated onto the thioredoxin ELISA plate and the other antibody is HRP-conjugated. The thioredoxin assay can be used to measure soluble human thioredoxin protein in serum, EDTA-plasma, and urine, or in cell culture supernatant.
Antibodies for Thioredoxin Detection
The anti-human thioredoxin antibody product (Cat. # 18651A) is an affinity-purified IgG antibody that recognizes human thioredoxin protein. The antibody was raised in rabbit using a synthetic peptide and can be used for Western blot (WB) detection of human thioredoxin protein.