Impaired acidification in early endosomes of ClC-5 deficient proximal tubule

Mariko Chikuma, Yinghong Wang, Sandra E. Guggino, William B. Guggino, A. S. Verkman

Research output: Contribution to journalArticle

97 Citations (Scopus)

Abstract

ClC-5 chloride channel deficiency causes proteinuria, hypercalciuria, and nephrolithiasis (Dent's disease). Impaired endosomal acidification in proximal tubule caused by reduced chloride conductance is a proposed mechanism; however, functional analysis of ClC-5 in oocytes predicts low ClC-5 chloride conductance in endosomes because of their acid interior pH and positive potential. Here, endosomal pH and chloride concentration were measured in proximal tubule cell cultures from wildtype vs. ClC-5 deficient mice using fluorescent sensors coupled to transferrin (early/recycling endosomes) or α2- macroglobulin (late endosomes). Initial pH in transferrin-labeled endosomes was ∼7.2, decreasing at 15 min to 6.0 vs. 6.5 in wildtype vs. ClC-5 deficient cells, respectively; corresponding endosomal chloride concentration increased from ∼16 mM to 47 vs. 36 mM. In contrast, acidification and chloride accumulation were not impaired in late endosomes or Golgi. Our results provide direct evidence for ClC-5 involvement in acidification of early endosomes in proximal tubule by a chloride shunt mechanism.

Original languageEnglish
Pages (from-to)941-946
Number of pages6
JournalBiochemical and Biophysical Research Communications
Volume329
Issue number3
DOIs
Publication statusPublished - 2005 Apr 15
Externally publishedYes

Fingerprint

Acidification
Endosomes
Chlorides
Transferrin
Dent Disease
Macroglobulins
Functional analysis
Hypercalciuria
Nephrolithiasis
Cell culture
Recycling
Proteinuria
Oocytes
Cell Culture Techniques
Acids
Sensors

Keywords

  • Chloride transport
  • Endocytosis
  • Macroglobulin
  • Ratioimaging
  • Transferrin

ASJC Scopus subject areas

  • Biochemistry
  • Biophysics
  • Molecular Biology

Cite this

Impaired acidification in early endosomes of ClC-5 deficient proximal tubule. / Chikuma, Mariko; Wang, Yinghong; Guggino, Sandra E.; Guggino, William B.; Verkman, A. S.

In: Biochemical and Biophysical Research Communications, Vol. 329, No. 3, 15.04.2005, p. 941-946.

Research output: Contribution to journalArticle

Chikuma, Mariko ; Wang, Yinghong ; Guggino, Sandra E. ; Guggino, William B. ; Verkman, A. S. / Impaired acidification in early endosomes of ClC-5 deficient proximal tubule. In: Biochemical and Biophysical Research Communications. 2005 ; Vol. 329, No. 3. pp. 941-946.
@article{1cd64001aa9f45ab91933e7dcf412443,
title = "Impaired acidification in early endosomes of ClC-5 deficient proximal tubule",
abstract = "ClC-5 chloride channel deficiency causes proteinuria, hypercalciuria, and nephrolithiasis (Dent's disease). Impaired endosomal acidification in proximal tubule caused by reduced chloride conductance is a proposed mechanism; however, functional analysis of ClC-5 in oocytes predicts low ClC-5 chloride conductance in endosomes because of their acid interior pH and positive potential. Here, endosomal pH and chloride concentration were measured in proximal tubule cell cultures from wildtype vs. ClC-5 deficient mice using fluorescent sensors coupled to transferrin (early/recycling endosomes) or α2- macroglobulin (late endosomes). Initial pH in transferrin-labeled endosomes was ∼7.2, decreasing at 15 min to 6.0 vs. 6.5 in wildtype vs. ClC-5 deficient cells, respectively; corresponding endosomal chloride concentration increased from ∼16 mM to 47 vs. 36 mM. In contrast, acidification and chloride accumulation were not impaired in late endosomes or Golgi. Our results provide direct evidence for ClC-5 involvement in acidification of early endosomes in proximal tubule by a chloride shunt mechanism.",
keywords = "Chloride transport, Endocytosis, Macroglobulin, Ratioimaging, Transferrin",
author = "Mariko Chikuma and Yinghong Wang and Guggino, {Sandra E.} and Guggino, {William B.} and Verkman, {A. S.}",
year = "2005",
month = "4",
day = "15",
doi = "10.1016/j.bbrc.2005.02.060",
language = "English",
volume = "329",
pages = "941--946",
journal = "Biochemical and Biophysical Research Communications",
issn = "0006-291X",
publisher = "Academic Press Inc.",
number = "3",

}

TY - JOUR

T1 - Impaired acidification in early endosomes of ClC-5 deficient proximal tubule

AU - Chikuma, Mariko

AU - Wang, Yinghong

AU - Guggino, Sandra E.

AU - Guggino, William B.

AU - Verkman, A. S.

PY - 2005/4/15

Y1 - 2005/4/15

N2 - ClC-5 chloride channel deficiency causes proteinuria, hypercalciuria, and nephrolithiasis (Dent's disease). Impaired endosomal acidification in proximal tubule caused by reduced chloride conductance is a proposed mechanism; however, functional analysis of ClC-5 in oocytes predicts low ClC-5 chloride conductance in endosomes because of their acid interior pH and positive potential. Here, endosomal pH and chloride concentration were measured in proximal tubule cell cultures from wildtype vs. ClC-5 deficient mice using fluorescent sensors coupled to transferrin (early/recycling endosomes) or α2- macroglobulin (late endosomes). Initial pH in transferrin-labeled endosomes was ∼7.2, decreasing at 15 min to 6.0 vs. 6.5 in wildtype vs. ClC-5 deficient cells, respectively; corresponding endosomal chloride concentration increased from ∼16 mM to 47 vs. 36 mM. In contrast, acidification and chloride accumulation were not impaired in late endosomes or Golgi. Our results provide direct evidence for ClC-5 involvement in acidification of early endosomes in proximal tubule by a chloride shunt mechanism.

AB - ClC-5 chloride channel deficiency causes proteinuria, hypercalciuria, and nephrolithiasis (Dent's disease). Impaired endosomal acidification in proximal tubule caused by reduced chloride conductance is a proposed mechanism; however, functional analysis of ClC-5 in oocytes predicts low ClC-5 chloride conductance in endosomes because of their acid interior pH and positive potential. Here, endosomal pH and chloride concentration were measured in proximal tubule cell cultures from wildtype vs. ClC-5 deficient mice using fluorescent sensors coupled to transferrin (early/recycling endosomes) or α2- macroglobulin (late endosomes). Initial pH in transferrin-labeled endosomes was ∼7.2, decreasing at 15 min to 6.0 vs. 6.5 in wildtype vs. ClC-5 deficient cells, respectively; corresponding endosomal chloride concentration increased from ∼16 mM to 47 vs. 36 mM. In contrast, acidification and chloride accumulation were not impaired in late endosomes or Golgi. Our results provide direct evidence for ClC-5 involvement in acidification of early endosomes in proximal tubule by a chloride shunt mechanism.

KW - Chloride transport

KW - Endocytosis

KW - Macroglobulin

KW - Ratioimaging

KW - Transferrin

UR - http://www.scopus.com/inward/record.url?scp=14844293074&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=14844293074&partnerID=8YFLogxK

U2 - 10.1016/j.bbrc.2005.02.060

DO - 10.1016/j.bbrc.2005.02.060

M3 - Article

C2 - 15752747

AN - SCOPUS:14844293074

VL - 329

SP - 941

EP - 946

JO - Biochemical and Biophysical Research Communications

JF - Biochemical and Biophysical Research Communications

SN - 0006-291X

IS - 3

ER -