DuoxA (Dual oxidase maturation factor) is the essential protein necessary for the final release of DUOX2 (an NADPH:O2 oxidoreductase flavoprotein) from the endoplasmic reticulum. Dual oxidases (DUOX1 and DUOX2) constitute the catalytic core of the hydrogen peroxide generator, which generates H2O2 at the apical membrane of thyroid follicular cells, essential for iodination of thyroglobulin by thyroid peroxidases. DuoxA carries five membrane-integral regions including a reverse signal-anchor with external N-terminus (type III) and two N-glycosylation sites [1]. It is conserved from nematodes to humans.

1: Identification of the maturation factor for dual oxidase. Evolution of an eukaryotic operon equivalent. Grasberger H, Refetoff S; J Biol Chem. 2006;281:18269-18272. PMID:16651268