TXN

The protein encoded by this gene acts as a homodimer and is involved in many redox reactions. The encoded protein is active in the reversible S-nitrosylation of cysteines in certain proteins, which is part of the response to intracellular nitric oxide. This protein is found in the cytoplasm. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2011]

TXN Gene(Protein Coding) Thioredoxin

Participates in various redox reactions through the reversible oxidation of its active center dithiol to a disulfide and catalyzes dithiol-disulfide exchange reactions (PubMed:2176490, PubMed:17182577, PubMed:19032234).
Plays a role in the reversible S-nitrosylation of cysteine residues in target proteins, and thereby contributes to the response to intracellular nitric oxide. Nitrosylates the active site Cys of CASP3 in response to nitric oxide (NO), and thereby inhibits caspase-3 activity (PubMed:16408020, PubMed:17606900).
Induces the FOS/JUN AP-1 DNA-binding activity in ionizing radiation (IR) cells through its oxidation/reduction status and stimulates AP-1 transcriptional activity (PubMed:9108029, PubMed:11118054).
ADF augments the expression of the interleukin-2 receptor TAC (IL2R/P55).

Biological Process activation of protein kinase B activity Source:ParkinsonsUK-UCL1 Publication
Biological Process cell redox homeostasis Source:UniProtKB1 Publication
Biological Process negative regulation of hydrogen peroxide-induced cell death Source:ParkinsonsUK-UCL1 Publication
Biological Process negative regulation of protein export from nucleus Source:Ensembl
Biological Process negative regulation of transcription by RNA polymerase II Source:Ensembl
Biological Process positive regulation of DNA binding Source:UniProtKB1 Publication
Biological Process positive regulation of peptidyl-cysteine S-nitrosylation Source:UniProtKB3 Publications
Biological Process positive regulation of peptidyl-serine phosphorylation Source:ParkinsonsUK-UCL1 Publication
Biological Process positive regulation of protein kinase B signaling Source:ParkinsonsUK-UCL1 Publication
Biological Process response to nitric oxide Source:UniProtKB2 Publications
Biological Process response to radiation Source:UniProtKB2 Publications

Nucleus
Cytoplasm
Secreted
Translocates from the cytoplasm into the nucleus after phorbol 12-myristate 13-acetate induction (PMA) (PubMed:9108029).
Predominantly in the cytoplasm in non irradiated cells (PubMed:11118054).
Radiation induces translocation of TRX from the cytoplasm to the nucleus (PubMed:11118054).
Secreted by a leaderless secretory pathway (PubMed:1332947).

Causes an allergic reaction in human (PubMed:17182577, PubMed:19032234, PubMed:21489611).
Recombinant protein binds to IgE in atopic eczema-suffering patients allergic to opportunistic skin-colonizing yeast M.sympodialis. Intermediate cross-reactivity is detected between the recombinant thioredoxin from M.sympodialis (Mala s 13) and recombinant form of this protein. Skin-prick test (SPT) and atopy patch test (APT) with 5 patients confirm cross-reactivity between the two proteins (PubMed:17182577).
Recombinant protein binds to IgE of patients suffering from allergic bronchopulmonary aspergillosis (ABPA) and cross-reacts extensively with recombinant thioredoxin proteins from A.fumigatus (Asp f 28 and Asp f 29) and Mala s 13. Causes a positive skin reaction and induces proliferation of the human peripheral blood mononuclear cells in ABPA patients allergic to this protein. Acts as an IgE-binding self-antigen in ABPA patients allergic to fungal thioredoxin (PubMed:19032234).
In atopic dermatitis (AD)-suffering patients allergic to M.sympodialis, a cross-reactivity between Mala s 13 and this protein can be detected in T-cells of the peripheral blood and skin. Keratinocytes stimulated by interferon (IFN)-alpha and tumor necrosis factor (TNF)-alpha release thioredoxin, which then becomes available for cross-reactivity with Mala s 13-specific T cells. The autoreactive T cells identified include T-helper 1 (Th1), T-helper 2 (Th2), T-helper 17 (Th17) and T-helper 22 (Th22) phenotypes. Skinhoming T cells autoreactive to this protein may be relevant for cutaneous inflammation in patients with AD (PubMed:21489611).

In the fully reduced protein, both Cys-69 and Cys-73 are nitrosylated in response to nitric oxide (NO). When two disulfide bonds are present in the protein, only Cys-73 is nitrosylated. Cys-73 can serve as donor for nitrosylation of target proteins.
In case of infection, ubiquitinated by S.typhimurium protein slrP, leading to its degradation.