Aquaporin 3 cloned from Xenopus laevis is regulated by the cystic fibrosistransmembrane conductance regulator

The cystic fibrosis transmembrane conductance regulator (CFTR) is essential for epithelial electrolyte transport and has been shown to be a regulator of epithelial Na+, K+, and Cl- channels. CFTR also enhances osmotic water p ermeability when activated by cAMP. This was detected initially in Xenopus oocytes and is also present in human airway epithelial cells, however, the mechanisms remain obscure, Here, we show that CFTR activates aquaporin 3 ex pressed endogenously and exogenously in oocytes of Xenopus laevis, The inte raction requires stimulation of wild type CFTR by cAMP and an intact first nucleotide binding domain as demonstrated for other CFTR-protein interactio ns. (C) 2000 Federation of European Biochemical Societies. Published by Els evier Science B.V. All rights reserved.