Uroplakin-2 is a single-pass type I membrane protein that belongs to the uroplakin-2 family. Uroplakin-2 is a component of the asymmetric unit membrane (AUM) and expressed in the ureter, a highly specialized biomembrane elaborated by terminally differentiated urothelial cells. Uroplakin-2 forms heterodimer with UPK1A that is necessary for exiting out of the endoplasmic reticulum (ER). Uroplakin-2 may play an important role in regulating the assembly of the AUM. AUM is believed to strengthen the urothelium by preventing cell rupture during bladder distention.