Critical component of the membrane-bound oxidase of phagocytes that generates superoxide. Associates with NOX3 to form a functional NADPH oxidase constitutively generating superoxide. Composed of a heavy chain (beta) and a light chain (alpha). Component of an NADPH oxidase complex composed of a heterodimer formed by the membrane proteins CYBA and CYBB and the cytosolic subunits NCF1, NCF2 and NCF4. Interacts with NCF1 (via SH3 domain). Interacts with DUOX1, DUOX2 and TPO. Interacts with NOX3 and NOX4. Interacts with calprotectin (S100A8/9) (By similarity). Interacts with SH3PXD2A (PubMed:19755709). Interacts with GBP7 (PubMed:21551061). As unassembled monomer may localize to the endoplasmic reticulum. The strongest level of expression is found in kidney, peritoneal neutrophils and peritoneal macrophages, and a lower level in spleen and small intestine. Very low level of expression can be noted in brain, liver, testis, and heart. The heme prosthetic group could be coordinated with residues of the light chain, the heavy chain, or both, and it is possible that more than one heme is present per cytochrome b-245. Phosphorylation at Thr-147 enhances NADPH oxidase activity by promoting p47phox binding. Ubiquitinated at Lys-149 likely by RNF145. Mice show defects in invadopodia biogenesis (PubMed:19755709). Mutants have a very sever defect in controlling bacterial replication (PubMed:28351984). Mice show spontaneous trunk curland head bobbing and fail to exhibit contact-rghting reflex (PubMed:28351984). Belongs to the p22phox family.