Fig. 3: Uroplakins form asymmetric unit membrane (AUM) particles.
From: The urothelium: a multi-faceted barrier against a harsh environment
Uroplakins embedded in a lipid bilayer are arranged in 16-nm AUM particles. The AUM inner ring is comprised of UPK1A-UPK2 heterodimers, and the outer ring is formed by UPK3A-UPK1B heterodimers. UPK3A and UPK2 moieties interact to form heterotetradimers.
