title: Slc26a11, a chloride transporter, localizes with the vacuolar H(+)-ATPase of A-intercalated cells of the kidney.
abstract: Chloride has an important role in regulating vacuolar H(+)-ATPase activity across specialized cellular and intracellular membranes. In the kidney, vacuolar H(+)-ATPase is expressed on the apical membrane of acid-secreting A-type intercalated cells in the collecting duct where it has an essential role in acid secretion and systemic acid base homeostasis. Here, we report the identification of a chloride transporter, which co-localizes with and regulates the activity of plasma membrane H(+)-ATPase in the kidney collecting duct. Immunoblotting and immunofluorescent labeling identified Slc26a11 (∼72 kDa), expressed in a subset of cells in the collecting duct. On the basis of double-immunofluorescent labeling with AQP2 and identical co-localization with H(+)-ATPase, cells expressing Slc26a11 were deemed to be distinct from principal cells and were found to be intercalated cells. Functional studies in transiently transfected COS7 cells indicated that Slc26a11 (designated as kidney brain anion transporter (KBAT)) can transport chloride and increase the rate of acid extrusion by means of H(+)-ATPase. Thus, Slc26a11 is a partner of vacuolar H(+)-ATPase facilitating acid secretion in the collecting duct.
authors.affiliation: Research Services, Veterans Affairs Medical Center, Cincinnati, Ohio, USA; Department of Medicine, University of Cincinnati, Cincinnati, Ohio, USA; Department of Orthodontics, University of Florida, Gainesville, Florida, USA; Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, Ohio, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Xu
authors.affiliation: Research Services, Veterans Affairs Medical Center, Cincinnati, Ohio, USA; Department of Medicine, University of Cincinnati, Cincinnati, Ohio, USA; Department of Orthodontics, University of Florida, Gainesville, Florida, USA; Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, Ohio, USA.
authors.forename: Sharon
authors.initials: S
authors.lastname: Barone
authors.affiliation: Research Services, Veterans Affairs Medical Center, Cincinnati, Ohio, USA; Department of Medicine, University of Cincinnati, Cincinnati, Ohio, USA; Department of Orthodontics, University of Florida, Gainesville, Florida, USA; Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, Ohio, USA.
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.affiliation: Research Services, Veterans Affairs Medical Center, Cincinnati, Ohio, USA; Department of Medicine, University of Cincinnati, Cincinnati, Ohio, USA; Department of Orthodontics, University of Florida, Gainesville, Florida, USA; Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, Ohio, USA.
authors.forename: Shannon
authors.initials: S
authors.lastname: Holiday
authors.affiliation: Research Services, Veterans Affairs Medical Center, Cincinnati, Ohio, USA; Department of Medicine, University of Cincinnati, Cincinnati, Ohio, USA; Department of Orthodontics, University of Florida, Gainesville, Florida, USA; Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, Ohio, USA.
authors.forename: Kamyar
authors.initials: K
authors.lastname: Zahedi
authors.affiliation: Research Services, Veterans Affairs Medical Center, Cincinnati, Ohio, USA; Department of Medicine, University of Cincinnati, Cincinnati, Ohio, USA; Department of Orthodontics, University of Florida, Gainesville, Florida, USA; Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, Ohio, USA. Electronic address: Manoocher.Soleimani@uc.edu.
authors.forename: Manoocher
authors.initials: M
authors.lastname: Soleimani
mesh_terms: D000818:Animals; D027321:Anion Transport Proteins / Q000235:genetics / Q000378:metabolism*; D051399:Aquaporin 2 / Q000378:metabolism; D001639:Bicarbonates / Q000378:metabolism; D001692:Biological Transport; D015153:Blotting, Western; D019556:COS Cells; D002712:Chlorides / Q000378:metabolism*; D002522:Chlorocebus aethiops; D005455:Fluorescent Antibody Technique; D006863:Hydrogen-Ion Concentration; D007685:Kidney Tubules, Collecting / Q000166:cytology / Q000201:enzymology*; D051379:Mice; D008810:Mice, Inbred C57BL; D051381:Rats; D017207:Rats, Sprague-Dawley; D000076988:Sulfate Transporters; D013997:Time Factors; D014162:Transfection; D025262:Vacuolar Proton-Translocating ATPases / Q000378:metabolism*
chemical_list: D027321:Anion Transport Proteins; C496024:Aqp2 protein, mouse; D051399:Aquaporin 2; D001639:Bicarbonates; D002712:Chlorides; C513264:Slc26a2 protein, mouse; D000076988:Sulfate Transporters; D025262:Vacuolar Proton-Translocating ATPases