DOMON:: an ancient extracellular domain in dopamine β-monooxygenase and other proteins

A previously uncharacterized 110-125 residue-long domain was identified both in the physiologically important enzyme dopamine P-monooxygenase and in several other secreted and transmembrane proteins such as SDR2 and CG-6. This domain was predicted to adopt an all-beta fold with seven or eight strands and might function as a module mediating a range of extracellular adhesive interactions.