E3 binding protein also known as pyruvate dehydrogenase protein X component, mitochondrial is a protein that in humans is encoded by the PDHXgene.[5][6][7][8] The E3 binding protein is a component of the pyruvate dehydrogenase complex found only in eukaryotes. Defects in this gene are a cause of pyruvate dehydrogenase deficiency which results in neurological dysfunction and lactic acidosis in infancy and early childhood. This protein is also a minor antigen for antimitochondrial antibodies. These autoantibodies are present in nearly 95% of patients with primary biliary cholangitis, an autoimmune disease of the liver. In primary biliary cholangitis, activated T lymphocytes attack and destroy epithelial cells in the bile duct where this protein is abnormally distributed and overexpressed. Primary biliary cholangitis eventually leads to liver failure.[5]
