Aquaporin-3 mediates hydrogen peroxide-dependent responses to environmental stress in colonic epithelia

Significance The extracellular production of hydrogen peroxide (H 2 O 2 ) by membrane or secreted oxidases has been linked to epithelial wound repair, defense against infection, and inflammation. Here, we elucidate the pathway that explains how extracellular H 2 O 2 transduces a signal into the cell to induce these critical cell functions. Our study shows the central component of this pathway in the mammalian colon is the H 2 O 2 -conducting aquaglyceroporin AQP3 and implicates this channel in innate immune responses at mucosal surfaces.