title: Immunolocalization of an inwardly rectifying K+ channel, K(AB)-2 (Kir4.1), in the basolateral membrane of renal distal tubular epithelia.
abstract: Immunolocalization of K(AB)-2 (Kir4.1), an inwardly rectifying K+ channel with a putative ATP-binding domain, was examined in rat kidney where expression of K(AB)-2 mRNA was previously shown. Anti-K(AB)-2 antibody was raised in rabbit and then affinity-purified. An immunohistochemical study revealed that K(AB)-2 immunoreactivity was detected specifically in the basolateral membrane of distal tubular epithelia. Therefore, K(AB)-2 is the first K+ channel shown to be localized in the basolateral membrane of renal epithelia. The finding suggests that K(AB)-2 may contribute to supplying K+ to the Na(+)-K+ pump, which is abundant in the basolateral membrane of distal tubular epithelia, as well as to maintenance of the deep negative membrane potential of these cells.
authors.affiliation: Department of Cell Biology and Signaling, Yamagata University School of Medicine, Yamagata, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Ito
authors.forename: A
authors.initials: A
authors.lastname: Inanobe
authors.forename: Y
authors.initials: Y
authors.lastname: Horio
authors.forename: H
authors.initials: H
authors.lastname: Hibino
authors.forename: S
authors.initials: S
authors.lastname: Isomoto
authors.forename: H
authors.initials: H
authors.lastname: Ito
authors.forename: K
authors.initials: K
authors.lastname: Mori
authors.forename: A
authors.initials: A
authors.lastname: Tonosaki
authors.forename: H
authors.initials: H
authors.lastname: Tomoike
authors.forename: Y
authors.initials: Y
authors.lastname: Kurachi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000918:Antibody Specificity; D002462:Cell Membrane / Q000737:chemistry; D004848:Epithelium / Q000737:chemistry; D007672:Kidney Cortex / Q000737:chemistry; D007686:Kidney Tubules, Distal / Q000737:chemistry*; D008297:Male; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000138:chemical synthesis / Q000276:immunology; D015221:Potassium Channels / Q000032:analysis*; D024661:Potassium Channels, Inwardly Rectifying; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar
chemical_list: D009842:Oligopeptides; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying