Claudin-2 (SP82)
1_MASLG 6_ LQLVG 11_ YILGL 16_ LGLLG 21_ TLVAM 26_ LLPSW 31_ KTSSY 36_ VGASI 41_ VTAVG 46_ FSKGL 51_ WMECA 56_ THSTG 61_ ITQCD 66_ IYSTL 71_ LGLPA 76_ DIQAA 81_ QAMMV 86_ TSSAI 91_ SSLAC 96_ IISVV 101_ GMRCT 106_ VFCQE 111_ SRAKD 116_ RVAVA 121_ GGVFF 126_ ILGGL 131_ LGFIP 136_ VAWNL 141_ HGILR 146_ DFYSP 151_ LVPDS 156_ MKFEI 161_ GEALY 166_ LGIIS 171_ SLFSL 176_ IAGII 181_ LCFSC 186_ SSQRN 191_ RSNYY 196_ DAYQA 201_ QPLAT 206_ RSSPR 211_ PGQPP 216_ KVKSE 221_FNSYS
1: Forms paracellular channels: polymerizes in tight junction strands with cation- and water-selective channels through the strands, conveying epithelial permeability in a process known as paracellular tight junction permeability (PubMed:20460438, PubMed:36008380). In intestinal epithelium, allows for sodium and water fluxes from the peritoneal side to the lumen of the intestine to regulate nutrient absorption and clear enteric pathogens as part of mucosal immune response (By similarity). In kidney, allows passive sodium and calcium reabsorption across proximal tubules from the lumen back to the bloodstream (By similarity). In the hepatobiliary tract, allows paracellular water and cation fluxes in the hepatic perivenous areas and biliary epithelium to generate bile flow and maintain osmotic gradients (By similarity)