DUOX1

DUOX1 (dual oxidase 1) is a member of the NADPH oxidase family that generates hydrogen peroxide (H₂O₂) and functions as a regulated source of reactive oxygen species in epithelial tissues^[1][2]. DUOX1 contains a distinctive extracellular peroxidase-like domain, seven transmembrane segments, and calcium-binding EF-hand motifs, enabling Ca²⁺-dependent activation and extracellular H₂O₂ production^[2][3]. Mechanistically, DUOX1 requires association with the maturation factor DUOXA1 for proper membrane localization and enzymatic activity, thereby supporting redox-dependent signaling pathways at mucosal surfaces^[2]. In the respiratory epithelium, DUOX1 contributes to innate host defense through controlled H₂O₂ generation and participates in epithelial responses to microbial stimulation and tissue injury^[1]. DUOX1 has also been implicated in airway epithelial migration and wound repair, linking redox signaling to epithelial regeneration processes^[1]. In disease-relevant models, DUOX1 promotes antiviral innate immunity in the airways, where its activity contributes to viral clearance and reduced disease severity during influenza infection^[4]. Compared with the closely related isoform DUOX2, which is more strongly expressed in the thyroid and is preferentially induced by Th1-associated signals, DUOX1 is prominently expressed in airway epithelium and is preferentially upregulated by the Th2 cytokines IL-4 and IL-13, indicating distinct immunological functions despite substantial sequence similarity between the two enzymes^[3][5]. For experimental applications, DUOX1 serves as a useful model for investigating epithelial redox biology, mucosal immunity, host-pathogen interactions, and ROS-dependent tissue repair mechanisms^[1][4].