NOX4 (NADPH Oxidase 4) is a Protein Coding gene. This gene encodes a member of the NOX-family of enzymes that functions as the catalytic subunit of the NADPH oxidase complex. The encoded protein is localized to non-phagocytic cells where it acts as an oxygen sensor and catalyzes the reduction of molecular oxygen to various reactive oxygen species (ROS). NOX4 has emerged as a significant source of reactive oxygen species, playing an important role in tumor cell proliferation, apoptosis, and other physiological processes. Its expression is increased in sepsis. NOX4 also plays a major role in renal oxidative stress of diabetic kidney disease (DKD). Diseases associated with NOX4 include Ureteral Obstruction and Pulmonary Hypertension.