The study identifies Renox, a renal NAD(P)H oxidase, which is homologous to gp91phox, the 91-kDa subunit of phagocyte NADPH oxidase. Renox is highly expressed in the renal cortex, particularly in proximal convoluted tubule epithelial cells, where it is likely involved in oxygen sensing and regulation of erythropoietin (EPO) synthesis. Overexpression of Renox in NIH 3T3 fibroblasts leads to increased superoxide production and signs of cellular senescence. The findings suggest that Renox may play a role in both physiological oxygen sensing and the development of inflammatory processes in the kidney.The study identifies Renox, a renal NAD(P)H oxidase, which is homologous to gp91phox, the 91-kDa subunit of phagocyte NADPH oxidase. Renox is highly expressed in the renal cortex, particularly in proximal convoluted tubule epithelial cells, where it is likely involved in oxygen sensing and regulation of erythropoietin (EPO) synthesis. Overexpression of Renox in NIH 3T3 fibroblasts leads to increased superoxide production and signs of cellular senescence. The findings suggest that Renox may play a role in both physiological oxygen sensing and the development of inflammatory processes in the kidney.