UPK1B

Uroplakin 1B, also known as UPK1B, is a is_associated_with::protein which in humans is encoded by the UPK1B is_associated_with::gene.

Function
The protein encoded by this gene is a member of the transmembrane 4 superfamily, also known as the is_associated_with::tetraspanin family. Most of these members are cell-surface proteins that are characterized by the presence of four hydrophobic domains. These proteins mediate is_associated_with::signal transduction events that play a role in the regulation of cell development, activation, growth and motility. This encoded protein is found in the asymmetrical unit membrane (AUM) where it can form a complex with other transmembrane 4 superfamily proteins. It may play a role in normal bladder epithelial physiology, possibly in regulating membrane permeability of superficial umbrella cells or in stabilizing the apical membrane through AUM/cytoskeletal interactions. The AUM is believed to be involved in strengthening the cells that line the is_associated_with::bladder, thus preventing these cells from rupturing during bladder distension. The use of alternate is_associated_with::polyadenylation sites has been found for this gene.