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The late endosomal ClC-6 mediates proton/chloride countertransport in heterologous plasma membrane expression.
Neagoe I
,
Stauber T
,
Fidzinski P
,
Bergsdorf EY
,
Jentsch TJ
.
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Members of the CLC protein family of Cl(-) channels and transporters display the remarkable ability to function as either chloride channels or Cl(-)/H(+) antiporters. Due to the intracellular localization of ClC-6 and ClC-7, it has not yet been possible to study the biophysical properties of these members of the late endosomal/lysosomal CLC branch in heterologous expression. Whereas recent data suggest that ClC-7 functions as an antiporter, transport characteristics of ClC-6 have remained entirely unknown. Here, we report that fusing the green fluorescent protein (GFP) to the N terminus of ClC-6 increased its cell surface expression, allowing us to functionally characterize ClC-6. Compatible with ClC-6 mediating Cl(-)/H(+) exchange, Xenopus oocytes expressing GFP-tagged ClC-6 alkalinized upon depolarization. This alkalinization was dependent on the presence of extracellular anions and could occur against an electrochemical proton gradient. As observed in other CLC exchangers, ClC-6-mediated H(+) transport was abolished by mutations in either the "gating" or "proton" glutamate. Overexpression of GFP-tagged ClC-6 in CHO cells elicited small, outwardly rectifying currents with a Cl(-) > I(-) conductance sequence. Mutating the gating glutamate of ClC-6 yielded an ohmic anion conductance that was increased by additionally mutating the "anion-coordinating" tyrosine. Additionally changing the chloride-coordinating serine 157 to proline increased the NO(3)(-) conductance of this mutant. Taken together, these data demonstrate for the first time that ClC-6 is a Cl(-)/H(+) antiporter.
Accardi,
Secondary active transport mediated by a prokaryotic homologue of ClC Cl- channels.
2004, Pubmed
Accardi,
Secondary active transport mediated by a prokaryotic homologue of ClC Cl- channels.
2004,
Pubmed
Accardi,
Separate ion pathways in a Cl-/H+ exchanger.
2005,
Pubmed
Beitz,
Determinants of AQP6 trafficking to intracellular sites versus the plasma membrane in transfected mammalian cells.
2006,
Pubmed
Bergsdorf,
Residues important for nitrate/proton coupling in plant and mammalian CLC transporters.
2009,
Pubmed
,
Xenbase
Brandt,
ClC-6 and ClC-7 are two novel broadly expressed members of the CLC chloride channel family.
1995,
Pubmed
,
Xenbase
Buyse,
Expression of human pICln and ClC-6 in Xenopus oocytes induces an identical endogenous chloride conductance.
1997,
Pubmed
,
Xenbase
De Angeli,
The nitrate/proton antiporter AtCLCa mediates nitrate accumulation in plant vacuoles.
2006,
Pubmed
Dutzler,
X-ray structure of a ClC chloride channel at 3.0 A reveals the molecular basis of anion selectivity.
2002,
Pubmed
Friedrich,
Mutational analysis demonstrates that ClC-4 and ClC-5 directly mediate plasma membrane currents.
1999,
Pubmed
,
Xenbase
Graves,
The Cl-/H+ antiporter ClC-7 is the primary chloride permeation pathway in lysosomes.
2008,
Pubmed
Günther,
ClC-5, the chloride channel mutated in Dent's disease, colocalizes with the proton pump in endocytotically active kidney cells.
1998,
Pubmed
Günther,
The ClC-5 chloride channel knock-out mouse - an animal model for Dent's disease.
2003,
Pubmed
Hara-Chikuma,
Impaired acidification in early endosomes of ClC-5 deficient proximal tubule.
2005,
Pubmed
Hara-Chikuma,
ClC-3 chloride channels facilitate endosomal acidification and chloride accumulation.
2005,
Pubmed
Ignoul,
Human ClC-6 is a late endosomal glycoprotein that associates with detergent-resistant lipid domains.
2007,
Pubmed
Jayaram,
Ion permeation through a Cl--selective channel designed from a CLC Cl-/H+ exchanger.
2008,
Pubmed
Jentsch,
CLC chloride channels and transporters: from genes to protein structure, pathology and physiology.
2008,
Pubmed
Jentsch,
Chloride and the endosomal-lysosomal pathway: emerging roles of CLC chloride transporters.
2007,
Pubmed
Kasper,
Loss of the chloride channel ClC-7 leads to lysosomal storage disease and neurodegeneration.
2005,
Pubmed
Kieferle,
Two highly homologous members of the ClC chloride channel family in both rat and human kidney.
1994,
Pubmed
Kornak,
Loss of the ClC-7 chloride channel leads to osteopetrosis in mice and man.
2001,
Pubmed
Lange,
ClC-7 requires Ostm1 as a beta-subunit to support bone resorption and lysosomal function.
2006,
Pubmed
Li,
The ClC-3 chloride channel promotes acidification of lysosomes in CHO-K1 and Huh-7 cells.
2002,
Pubmed
Li,
Biophysical properties of ClC-3 differentiate it from swelling-activated chloride channels in Chinese hamster ovary-K1 cells.
2000,
Pubmed
Lorenz,
Heteromultimeric CLC chloride channels with novel properties.
1996,
Pubmed
,
Xenbase
Ludewig,
Two physically distinct pores in the dimeric ClC-0 chloride channel.
1996,
Pubmed
,
Xenbase
Matsuda,
Overexpression of CLC-3 in HEK293T cells yields novel currents that are pH dependent.
2008,
Pubmed
Mohammad-Panah,
The chloride channel ClC-4 contributes to endosomal acidification and trafficking.
2003,
Pubmed
Nguitragool,
Uncoupling of a CLC Cl-/H+ exchange transporter by polyatomic anions.
2006,
Pubmed
Novarino,
Endosomal chloride-proton exchange rather than chloride conductance is crucial for renal endocytosis.
2010,
Pubmed
Picollo,
Chloride/proton antiporter activity of mammalian CLC proteins ClC-4 and ClC-5.
2005,
Pubmed
Picollo,
Basis of substrate binding and conservation of selectivity in the CLC family of channels and transporters.
2009,
Pubmed
Piwon,
ClC-5 Cl- -channel disruption impairs endocytosis in a mouse model for Dent's disease.
2000,
Pubmed
Poët,
Lysosomal storage disease upon disruption of the neuronal chloride transport protein ClC-6.
2006,
Pubmed
Scheel,
Voltage-dependent electrogenic chloride/proton exchange by endosomal CLC proteins.
2005,
Pubmed
,
Xenbase
Schwake,
An internalization signal in ClC-5, an endosomal Cl-channel mutated in dent's disease.
2001,
Pubmed
,
Xenbase
Steinmeyer,
Cloning and functional expression of rat CLC-5, a chloride channel related to kidney disease.
1995,
Pubmed
,
Xenbase
Suzuki,
Intracellular localization of ClC chloride channels and their ability to form hetero-oligomers.
2006,
Pubmed
Weinert,
Lysosomal pathology and osteopetrosis upon loss of H+-driven lysosomal Cl- accumulation.
2010,
Pubmed
Zdebik,
Determinants of anion-proton coupling in mammalian endosomal CLC proteins.
2008,
Pubmed
Zifarelli,
Conversion of the 2 Cl(-)/1 H+ antiporter ClC-5 in a NO3(-)/H+ antiporter by a single point mutation.
2009,
Pubmed
,
Xenbase
