FunctionComponent of the asymmetric unit membrane (AUM); a highly specialized biomembrane elaborated by terminally differentiated urothelial cells. May play an important role in AUM-cytoskeleton interaction in terminally differentiated urothelial cells. It also contributes to the formation of urothelial glycocalyx which may play an important role in preventing bacterial adherence.
Tissue specificityExpressed in ureter.
Involvement in diseaseDefects in UPK3A are a cause of renal adysplasia (RADYS) [MIM:191830]; also known as renal agenesis or renal aplasia. Renal agenesis refers to the absence of one (unilateral) or both (bilateral) kidneys at birth. Bilateral renal agenesis belongs to a group of perinatally lethal renal diseases, including severe bilateral renal dysplasia, unilateral renal agenesis with contralateral dysplasia and severe obstructive uropathy.
Sequence similaritiesBelongs to the uroplakin-3 family.
Cellular localizationEndoplasmic reticulum membrane. Heterodimer formation with UPK1B is a prerequisite to exit out of the endoplasmic reticulum (ER).