1. Academic Validation
  2. Mislocalization of K+ channels causes the renal salt wasting in EAST/SeSAME syndrome

Mislocalization of K+ channels causes the renal salt wasting in EAST/SeSAME syndrome

  • FEBS Lett. 2014 Mar 18;588(6):899-905. doi: 10.1016/j.febslet.2014.02.024.
Masayuki Tanemoto 1 Takaaki Abe 2 Shunya Uchida 3 Katsumasa Kawahara 4
Affiliations

Affiliations

  • 1 Division of Nephrology, Department of Internal Medicine, Teikyo University School of Medicine, Tokyo 174-8605, Japan. Electronic address: mtanemoto-tky@umin.ac.jp.
  • 2 Division of Medical Science, Tohoku University Graduate School of Biomedical Engineering, Sendai 980-8575, Japan.
  • 3 Division of Nephrology, Department of Internal Medicine, Teikyo University School of Medicine, Tokyo 174-8605, Japan.
  • 4 Department of Cellular and Molecular Physiology, Kitasato University Graduate School of Medical Sciences, Sagamihara 252-0374, Japan.
Abstract

The Kir4.1/Kir5.1 channel mediates basolateral K(+) recycling in renal distal tubules; this process is critical for Na(+) reabsorption at the tubules. Mutations in Kir4.1 are associated with EAST/SeSAME syndrome, a genetic disorder characterized by renal salt wasting. In this study, we found that MAGI-1 anchors Kir4.1 channels (Kir4.1 homomer and Kir4.1/Kir5.1 heteromer) and contributes to basolateral K(+) recycling. The Kir4.1 A167V mutation associated with EAST/SeSAME syndrome caused mistrafficking of the mutant channels and inhibited their expression on the basolateral surface of tubular cells. These findings suggest mislocalization of the Kir4.1 channels contributes to renal salt wasting.

Keywords

EAST/SeSAME syndrome; Epithelial sodium transport; Intracellular trafficking; Kidney; Potassium channel; Tubulopathy.

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