Cloning, cellular distribution and functional expression of small intestinal epithelium guinea pig C1C-5 chloride channel

We report the cloning of a guinea pig ClC-5 chloride channel (gpClC-5) from distal small intestinal epithelial cells by RT-PCR and RACE. The transcrip t is shown to be present in duodenum, jejunum and ileum epithelium by RT-PC R and Northern analysis. This is confirmed by in situ hybridisation which a lso shows the transcript to be homogeneously distributed in the crypt and v illus regions. Expression of gpClC-5 in HEK-293 cells generated markedly ou twardly rectified chloride currents with a perm-selectivity sequence of NO3 - > Cl- > Br- > I- > F- > gluconate(-). The possible role of gpClC5 in this epithelial location is discussed. (C) 2001 Elsevier Science B.V. All right s reserved.