PMID- 25609088 OWN - NLM STAT- MEDLINE DCOM- 20151204 LR - 20191008 IS - 1939-4586 (Electronic) IS - 1059-1524 (Print) IS - 1059-1524 (Linking) VI - 26 IP - 6 DP - 2015 Mar 15 TI - Increased water flux induced by an aquaporin-1/carbonic anhydrase II interaction. PG - 1106-18 LID - 10.1091/mbc.E14-03-0812 [doi] AB - Aquaporin-1 (AQP1) enables greatly enhanced water flux across plasma membranes. The cytosolic carboxy terminus of AQP1 has two acidic motifs homologous to known carbonic anhydrase II (CAII) binding sequences. CAII colocalizes with AQP1 in the renal proximal tubule. Expression of AQP1 with CAII in Xenopus oocytes or mammalian cells increased water flux relative to AQP1 expression alone. This required the amino-terminal sequence of CAII, a region that binds other transport proteins. Expression of catalytically inactive CAII failed to increase water flux through AQP1. Proximity ligation assays revealed close association of CAII and AQP1, an effect requiring the second acidic cluster of AQP1. This motif was also necessary for CAII to increase AQP1-mediated water flux. Red blood cell ghosts resealed with CAII demonstrated increased osmotic water permeability compared with ghosts resealed with albumin. Water flux across renal cortical membrane vesicles, measured by stopped-flow light scattering, was reduced in CAII-deficient mice compared with wild-type mice. These data are consistent with CAII increasing water conductance through AQP1 by a physical interaction between the two proteins. CI - (c) 2015 Vilas, Krishnan, Loganathan, et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution-Noncommercial-Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0). FAU - Vilas, Gonzalo AU - Vilas G AD - Department of Biochemistry, University of Alberta, Edmonton, AB T6G 1C9, Canada. FAU - Krishnan, Devishree AU - Krishnan D AD - Department of Physiology, University of Alberta, Edmonton, AB T6G 1C9, Canada Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB T6G 1C9, Canada. FAU - Loganathan, Sampath Kumar AU - Loganathan SK AD - Department of Biochemistry, University of Alberta, Edmonton, AB T6G 1C9, Canada Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB T6G 1C9, Canada. FAU - Malhotra, Darpan AU - Malhotra D AD - Department of Biochemistry, University of Alberta, Edmonton, AB T6G 1C9, Canada Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB T6G 1C9, Canada. FAU - Liu, Lei AU - Liu L AD - Department of Physiology, University of Alberta, Edmonton, AB T6G 1C9, Canada Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB T6G 1C9, Canada. FAU - Beggs, Megan Rachele AU - Beggs MR AD - Department of Physiology, University of Alberta, Edmonton, AB T6G 1C9, Canada Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB T6G 1C9, Canada. FAU - Gena, Patrizia AU - Gena P AD - Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70121 Bari, Italy. FAU - Calamita, Giuseppe AU - Calamita G AD - Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70121 Bari, Italy. FAU - Jung, Martin AU - Jung M AD - Department of Medical Biochemistry and Molecular Biology, Saarland University, D-66424 Homburg, Germany. FAU - Zimmermann, Richard AU - Zimmermann R AD - Department of Medical Biochemistry and Molecular Biology, Saarland University, D-66424 Homburg, Germany. FAU - Tamma, Grazia AU - Tamma G AD - Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70121 Bari, Italy. FAU - Casey, Joseph Roman AU - Casey JR AD - Department of Biochemistry, University of Alberta, Edmonton, AB T6G 1C9, Canada Department of Physiology, University of Alberta, Edmonton, AB T6G 1C9, Canada Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB T6G 1C9, Canada. FAU - Alexander, Robert Todd AU - Alexander RT AD - Department of Physiology, University of Alberta, Edmonton, AB T6G 1C9, Canada Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB T6G 1C9, Canada Department of Pediatrics, University of Alberta, Edmonton, AB T6G 1C9, Canada todd2@ualberta.ca. LA - eng GR - 106464-2/Canadian Institutes of Health Research/Canada GR - 96175-1/Canadian Institutes of Health Research/Canada GR - 96175-2/Canadian Institutes of Health Research/Canada GR - 106464-1/Canadian Institutes of Health Research/Canada GR - 136891-1/Canadian Institutes of Health Research/Canada PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20150121 PL - United States TA - Mol Biol Cell JT - Molecular biology of the cell JID - 9201390 RN - 0 (AQP1 protein, human) RN - 059QF0KO0R (Water) RN - 146410-94-8 (Aquaporin 1) RN - EC 4.2.1.- (Carbonic Anhydrase II) SB - IM MH - Amino Acid Sequence MH - Animals MH - Aquaporin 1/*metabolism MH - Carbonic Anhydrase II/*metabolism MH - Cell Membrane Permeability MH - Cells, Cultured MH - Erythrocytes/metabolism MH - HEK293 Cells MH - Humans MH - Molecular Sequence Data MH - Protein Binding MH - Protein Interaction Mapping MH - Water/*metabolism MH - Xenopus laevis PMC - PMC4357510 EDAT- 2015/01/23 06:00 MHDA- 2015/12/15 06:00 PMCR- 2015/05/30 CRDT- 2015/01/23 06:00 PHST- 2015/01/23 06:00 [entrez] PHST- 2015/01/23 06:00 [pubmed] PHST- 2015/12/15 06:00 [medline] PHST- 2015/05/30 00:00 [pmc-release] AID - mbc.E14-03-0812 [pii] AID - E14-03-0812 [pii] AID - 10.1091/mbc.E14-03-0812 [doi] PST - ppublish SO - Mol Biol Cell. 2015 Mar 15;26(6):1106-18. doi: 10.1091/mbc.E14-03-0812. Epub 2015 Jan 21.