PX domain of neutrophil cytosol factor 1 (PX domain of p47phox)

The PX domain of p47phox is a phosphoinositide-binding protein domain (~120-125 amino acids) present in the N-terminal region of the p47phox (neutrophil cytosol factor 1) subunit of phagocyte NADPH oxidase[6][2][3]. The PX domain specifically binds to phosphoinositides including phosphatidylinositol 3,4-bisphosphate (PI(3,4)P2) and phosphatidylinositol 3-phosphate (PI(3)P), and this binding is crucial for the regulated membrane translocation of p47phox[2][4][3]. Upon cell activation and phosphorylation, the PX domain is released from an intramolecular autoinhibitory state, allowing interaction with phosphoinositides, driving membrane localization and assembly of the active NADPH oxidase complex[1][2][7]. The correct function of this domain is essential for the oxidative burst of neutrophils and other phagocytes[1][4]. Genetic mutations in the PX domain that impair lipid binding have been linked to chronic granulomatous disease, a serious immunodeficiency disorder[4]. The PX domain, as a module, is not a direct therapeutic target but is critical for ROS-mediated pathogen defense and inflammation[1][4][2].

Other names

PX domain of NOXO2Phox homology domain of p47phox

Not a direct therapeutic drug target; no confirmed mechanisms of action for drugs targeting this domain.