TXNL1 (thioredoxin like 1) is a cytoplasmic thioredoxin-fold protein with dual functions as both a redox-active enzyme and an ATP-independent chaperone 1. As a redox enzyme, TXNL1 exhibits thioredoxin activity with a redox potential of approximately -250 mV, capable of reducing disulfides in insulin, cystine, and glutathione disulfide through NADPH-dependent reactions coupled to thioredoxin reductase, though with lower catalytic efficiency than classical thioredoxin 12. Additionally, TXNL1 functions as a redox-active cofactor of the 26S proteasome, binding to the Rpn11 subunit and facilitating protein degradation through the ubiquitin-proteasome pathway 23. The protein also demonstrates chaperone activity independent of its redox function, preventing protein aggregation without requiring ATP or redox activity 1. TXNL1 plays critical roles in cellular stress responses and disease pathogenesis. Arsenic exposure specifically downregulates TXNL1 expression, promoting ROS-mediated malignant transformation in bronchial epithelial cells 4. In cancer, TXNL1 regulates cisplatin resistance through modulation of DNA repair protein XRCC1 5, while in cardiovascular disease, TXNL1 is involved in acute myocardial infarction through PANoptosis mechanisms 6. These findings establish TXNL1 as a multifunctional protein linking oxidative stress regulation, protein quality control, and disease pathogenesis.