The protein encoded by this gene is a member of the transmembrane 4 superfamily, also known as the tetraspanin family. Most of these members are cell-surface proteins that are characterized by the presence of four hydrophobic domains. The proteins mediate 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 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.[3]
↑Yuasa T, Yoshiki T, Isono T, Tanaka T, Hayashida H, Okada Y (Sep 1999). "Expression of transitional cell-specific genes, uroplakin Ia and II, in bladder cancer: detection of circulating cancer cells in the peripheral blood of metastatic patients". Int J Urol. 6 (6): 286–92. doi:10.1046/j.1442-2042.1999.00064.x. PMID10404304.
Wu XR, Medina JJ, Sun TT (1996). "Selective interactions of UPIa and UPIb, two members of the transmembrane 4 superfamily, with distinct single transmembrane-domained proteins in differentiated urothelial cells". J. Biol. Chem. 270 (50): 29752–9. doi:10.1074/jbc.270.50.29752. PMID8530366.
Kageyama S, Yoshiki T, Isono T, et al. (2003). "High expression of human uroplakin Ia in urinary bladder transitional cell carcinoma". Jpn. J. Cancer Res. 93 (5): 523–31. doi:10.1111/j.1349-7006.2002.tb01287.x. PMID12036448.
Grimwood J, Gordon LA, Olsen A, et al. (2004). "The DNA sequence and biology of human chromosome 19". Nature. 428 (6982): 529–35. doi:10.1038/nature02399. PMID15057824.
Yuasa T, Yoshiki T, Isono T, et al. (2004). "Molecular cloning and expression of uroplakins in transitional cell carcinoma". Adv. Exp. Med. Biol. 539 (Pt A): 33–46. doi:10.1007/978-1-4419-8889-8_3. PMID15088894.
Hall GD, Weeks RJ, Olsburgh J, et al. (2005). "Transcriptional control of the human urothelial-specific gene, uroplakin Ia". Biochim. Biophys. Acta. 1729 (2): 126–34. doi:10.1016/j.bbaexp.2005.04.004. PMID15913809.