TRX1 Antibody
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- Deoxyribonucleotide synthesis
- Repair of oxidatively damaged proteins
- Protein folding
- Sulfur metabolism
- Redox homeostasis
TRX1 is a key component of thioredoxin-dependent enzymes, including:
- Phosphoadenosine-phosphosulfate reductase MET16
- Alkyl-hydroperoxide reductase DOT5
- Thioredoxin peroxidases TSA1 and TSA2
- Alkyl hydroperoxide reductase AHP1
- Peroxiredoxin HYR1
Furthermore, TRX1 contributes to protection against reducing stress. As part of the LMA1 complex, it facilitates vesicle fusion, such as homotypic vacuole and ER-derived COPII vesicle fusion with the Golgi. Notably, this activity does not rely on the redox mechanism.
- NMR spectroscopic studies of yeast TRX1 provide insights into the mechanism for the closing of the water cavity. PMID: 26482062
- TRX1 is essential for maintaining the IMS small Tim proteins in reduced forms, facilitating their mitochondrial import. PMID: 22878414
- Research indicates that an oxidized sulfiredoxin under disulfide state is formed between the catalytic Cys(84) and Cys(48), and this oxidized form is selectively reduced by thioredoxin. PMID: 19801666
- The cytosolic form of thioredoxin Trx1 has been cloned, expressed, purified, and crystallized. PMID: 18391437
- Human wt p53 expression in yeast leads to gene repression of thioredoxin (TRX1/2), a highly conserved multifunctional antioxidative and antiapoptotic protein family. PMID: 19054132
- X-ray diffraction analysis has been conducted on glutathionylated Trx1 C33S mutant from yeast. PMID: 19153453
- A study resolved the crystal structures of oxidized Trx1 and glutathionylated Trx1Cys33Ser mutant at 1.76 and 1.80 A, respectively. Kinetic studies demonstrated that the Met35Arg mutation could alter the apparent K(m) and V(max) values of the reaction. PMID: 19362171
- Trx1 and Trx2 are crucial for the nuclear accumulation of Msn2/4 and Maf1. PMID: 19581440
KEGG: sce:YLR043C
STRING: 4932.YLR043C
Q&A
What validation protocols ensure specificity of TRX1 antibodies in detecting Thioredoxin 1?
To validate anti-Trx1 antibodies (e.g., mouse monoclonal IgG1 clone Trx1 ), researchers should:
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Use knockout controls: Compare signal intensity in wild-type vs. Trx1-deficient cell lines using western blotting (WB).
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Test cross-reactivity: Validate against recombinant Trx family proteins (e.g., Trx2, TrxR) via ELISA .
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Confirm subcellular localization: Perform fractionation followed by WB to verify cytoplasmic/nuclear distribution patterns observed in prostate cancer models .
Key validation data:
| Cell Line | Cytoplasmic Trx1 Signal (WB) | Nuclear Trx1 Signal (WB) |
|---|---|---|
| PrEC | 1.0 ± 0.2 | 0.8 ± 0.1 |
| LNCaP | 1.7 ± 0.3* | 2.1 ± 0.4* |
| PC3 | 2.4 ± 0.5* | 4.2 ± 0.6* |
| *Data normalized to PrEC; adapted from redox Western analyses |
How does experimental design influence TRX1 (anti-CD4) pharmacodynamic outcomes?
Phase I studies of anti-CD4 TRX1 demonstrated:
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Dose-dependent CD4 modulation: Saturation kinetics showed 90% receptor occupancy at ≥5 mg/kg doses .
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Time-resolved sampling: Free vs. total CD4 measurements required flow cytometry at 0, 24, 72, and 168 hr post-infusion .
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Compartmental modeling: A receptor-mediated PK/PD model incorporating internalization rates (k<sub>int</sub> = 0.15 hr<sup>-1</sup>) improved prediction of CD4 recovery timelines .
How do redox states of Trx1 impact antibody-based detection in cancer models?
Contradictory reports on Trx1’s pro-/anti-tumor roles stem from:
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Oxidation status: Despite elevated total Trx1 in PC3 prostate cancer cells (4.2-fold nuclear increase ), 60% exists in oxidized forms, reducing functional availability.
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Androgen modulation: R1881 treatment increases nuclear Trx1 in LNCaP cells (Δ=+150% at 24h ) but induces transient cytoplasmic oxidation (30% increase in disulfide bonds ).
Resolution strategy: -
Perform redox Western blotting with iodoacetamide alkylation to differentiate reduced/oxidized forms .
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Correlate with functional assays (e.g., insulin reduction activity) to confirm redox competence.
What mechanisms explain TRX1 (anti-CD4)-induced immune tolerance?
The anti-CD4 TRX1 antibody operates via:
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T-effector cell inhibition: Blocks CD4/MHC-II interactions (K<sub>D</sub> ≈ 1 nM ).
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T-regulatory cell preservation: Maintains CD25<sup>+</sup>FoxP3<sup>+</sup> populations (85% viability vs. 40% in alemtuzumab-treated cells ).
Clinical correlation: Phase Ib trials in cutaneous lupus showed sustained CD4<sup>+</sup> suppression (>28 days) without lymphocyte depletion .
How should researchers handle TRX1 stability issues in redox signaling studies?
Critical protocol modifications:
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Sample preparation: Use lysis buffers with 50 mM N-ethylmaleimide to arrest thiol-disulfide exchange .
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Storage conditions: Aliquot antibodies in 25% glycerol at -80°C; avoid freeze-thaw cycles >3× .
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Activity controls: Include recombinant Trx1 (1 µg/mL) as a positive control in insulin reduction assays .
What metrics validate TRX1 (anti-CD4) target engagement in vivo?
| Parameter | Value | Biological Impact |
|---|---|---|
| K<sub>on</sub> | 0.8 nM<sup>-1</sup>hr<sup>-1</sup> | Rapid CD4 binding |
| K<sub>off</sub> | 0.02 hr<sup>-1</sup> | Prolonged receptor occupancy |
| IC<sub>50</sub> | 1.2 µg/mL | 50% CD4 internalization |
Can TRX1 expression enhance CAR T-cell resilience in solid tumors?
Key findings from TRX1-engineered CAR T cells :
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Oxidative stress mitigation: TRX1 overexpression reduced intracellular ROS by 65% in hypoxic conditions (1% O<sub>2</sub>).
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Functional enhancement:
How do androgen signaling pathways complicate Trx1 biomarker studies?
In prostate cancer models:
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Nuclear translocation: R1881 treatment increases nuclear Trx1 in LNCaP (AR<sup>+</sup>) but not PC3 (AR<sup>-</sup>) cells .
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Therapeutic implications:
Why do some studies report pro-tumorigenic Trx1 activity despite its antioxidant role?
Context-dependent factors:
| Condition | Trx1 Function | Outcome |
|---|---|---|
| Normoxia | ROS scavenging | Tumor suppression |
| Chronic hypoxia | NF-κB activation | Chemoresistance |
| Androgen present | AR stabilization | Prostate cancer progression |
