Analysis of different complexes of type IIa sodium-dependent phosphate transporter in rat renal cortex using blue-native polyacrylamide gel electrophoresis

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Author(s)

    • Tanimura Ayako
    • Department of Clinical Nutrition, Institute of Health Biosciences, the University of Tokushima Graduate School
    • Taketani Yutaka
    • Department of Clinical Nutrition, Institute of Health Biosciences, the University of Tokushima Graduate School
    • Takeda Eiji
    • Department of Clinical Nutrition, Institute of Health Biosciences, the University of Tokushima Graduate School
    • Yamada Fumiyo
    • Department of Clinical Nutrition, Institute of Health Biosciences, the University of Tokushima Graduate School
    • Saito Akihito
    • Department of Applied Molecular Medicine, Niigata University Graduate School of Medicine and Dental Sciences
    • Ito Mikiko
    • Department of Food Science and Nutrition, School of Human Science and Environment, University of Hyogo
    • Kimura Toru
    • Department of Pharmacology, School of Medicine, Kyorin University
    • Anzai Naohiko
    • Department of Pharmacology, School of Medicine, Kyorin University
    • Horie Daisuke
    • Department of Clinical Nutrition, Institute of Health Biosciences, the University of Tokushima Graduate School
    • Yamamoto Hironori
    • Department of Clinical Nutrition, Institute of Health Biosciences, the University of Tokushima Graduate School
    • Miyamoto Ken-ichi
    • Department of Molecular Nutrition, Institute of Health Biosciences, the University of Tokushima Graduate School

Abstract

Type IIa sodium-dependent phosphate transporter (NaPi-IIa) can be localized in the apical plasma membrane of renal proximal tubule to carry out a rate-limiting step of phosphate reabsorption. For the apical localization, NaPi-IIa is required to form a macromolecular complex with some adaptor proteins such as Na<SUP>+</SUP>/H<SUP>+</SUP> exchanger regulatory factor 1 (NHERF-1) and ezrin. However, the detail of macromolecular complex containing NaPi-IIa in the apical membrane of the renal proximal tubular cells has not been clarified. In this study, we identified at least four different complexes (220, 480, 920, 1,100 kDa) containing NaPi-IIa by using blue-native polyacrylamide gel electrophoresis. Interestingly, LC-MS/MS analysis and immunoprecipitation analysis reveal that megalin is a component of larger complexs (920 and 1,100 kDa). In addition, NaPi-IIa can be heterogeneously co-localized with ezrin and megalin on the apical membrane of renal proximal tubuler cells by fluorescence microscopy analysis. These results suggest that NaPi-IIa can form some different complexes on the apical plasma membrane of renal proximal tubular cells. J. Med. Invest. 58: 140-147, February, 2011

Journal

  • The Journal of Medical Investigation

    The Journal of Medical Investigation 58(1,2), 140-147, 2011

    The University of Tokushima Faculty of Medicine

Codes

  • NII Article ID (NAID)
    130004465236
  • Text Lang
    ENG
  • ISSN
    1343-1420
  • Data Source
    J-STAGE 
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