Protein disulfide-isomerase A4–p22phox protein–protein interface (PDIA4–p22phox interface)

The Protein disulfide-isomerase A4 (PDIA4)–p22phox protein–protein interface is a regulatory molecular complex that links the endoplasmic reticulum (ER) protein folding machinery to the generation of reactive oxygen species (ROS). PDIA4, also known as ERP72, is an ER-resident chaperone that, under conditions of metabolic stress, physically interacts with p22phox (encoded by the CYBA gene), a critical transmembrane subunit of the NADPH oxidase (NOX) complex [PMID: 28094264]. This interaction facilitates the assembly and enzymatic activation of NOX, leading to elevated ROS production that can drive cellular dysfunction and apoptosis. In pancreatic beta cells, chronic activation of the PDIA4–p22phox interface is a major contributor to oxidative stress-induced failure and the progression of Type 2 diabetes [PMID: 33462218]. Research has identified this interface as a viable therapeutic target, with small molecule inhibitors like G1 showing efficacy in disrupting the interaction and preserving beta-cell mass and function in preclinical models. By specifically targeting the protein-protein interface, it is possible to modulate pathological ROS production while minimizing interference with the essential housekeeping functions of the individual proteins.

Other names

PDIA4–CYBA interfaceERP72–p22phox interactionProtein disulfide-isomerase A4–p22phox complex

Small molecule inhibition of the physical interaction between PDIA4 and the p22phox subunit, which prevents the assembly and activation of the NADPH oxidase complex, thereby reducing the generation of harmful reactive oxygen species (ROS).