UPK1B
Description
The UPK1B (uroplakin 1B) is a protein-coding gene located on chromosome 3.
UPK1B gene encodes the Uroplakin-1b (UP1b) protein, a member of the transmembrane 4 superfamily (tetraspanin family). These proteins have four hydrophobic domains and are involved in cell signaling, influencing development, activation, growth, and movement. UP1b resides in the asymmetrical unit membrane (AUM), where it forms complexes with other tetraspanin proteins. It may contribute to normal bladder epithelial function, potentially regulating membrane permeability in superficial umbrella cells or stabilizing the apical membrane via AUM/cytoskeletal interactions. The AUM is believed to strengthen bladder lining cells and enhance membrane stretching, preventing cell rupture during bladder distension. Alternative polyadenylation sites are used for this gene.
UPK1B protein is a component of the asymmetric unit membrane (AUM), a specialized membrane found in terminally differentiated urothelial cells. It likely plays a crucial role in maintaining normal bladder function, potentially by regulating the permeability of superficial umbrella cells or stabilizing the apical membrane through interactions with the AUM and cytoskeleton.
UPK1B is also known as TSPAN20, UPIB, UPK1.
