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Characterization of the putative chloride channel xClC-5 expressed in Xenopus laevis oocytes and comparison with endogenous chloride currents.
Schmieder S
,
Lindenthal S
,
Banderali U
,
Ehrenfeld J
.
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1. We recently cloned a putative chloride channel (xClC-5) from the renal cell line A6, which induced the appearance of a Cl- conductance not found in control oocytes after homologous expression in Xenopus oocytes. With the aim of increasing the Xenopus oocyte xClC-5 expression, we constructed a new plasmid in which the native 5' and 3' non-coding regions of xClC-5 were replaced by the non-coding regions of the Xenopus beta-globin sequence and in which a Kozak consensus site was introduced before the initiator ATG. 2. We then compared the induced currents Inative (induced by injection of cRNA presenting the native non-coding regions of xClC-5) and Ibeta-globin (induced by injection of cRNA presenting the non-coding regions of the Xenopus beta-globin sequence) investigating anion selectivity and anion blocker sensitivity. Several differences were found: (1) expression yield and oocyte surviving rate were largely increased by injecting (beta) xClC-5 cRNA, (2) the Ibeta-globin outward rectification score was 2.6 times that of Inative, (3) the anion conductivity sequence was nitrate > bromide > chloride > iodide > gluconate for Ibeta-globin and iodide > bromide > nitrate > chloride > gluconate for Inative, (4) 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), anthracene-9-carboxylic acid (9-AC), DIDS, lanthanum ions, cAMP and ionomycin-induced [Ca2+]i increase inhibited Inative but had no effect on Ibeta-globin, and (5) Inative showed considerable similarity to the previously reported endogenous current appearing after ClC-6 or pICln cRNA injection. 3. Comparison of Inative with the endogenous chloride current ICl,swell which develops under hyposmotic conditions demonstrated several similarities in their electrophysiological and pharmacological characteristics but were nevertheless distinguishable. 4. In vitro translation assays demonstrated that protein synthesis was much greater using the (beta) xClC-5 construct than that of xClC-5. Furthermore, immunoreactivity of membrane preparations of Xenopus oocytes was only observed with the (beta) xClC-5 construct, its intensity being positively correlated with Ibeta-globin levels. 5. In addition, the current induced in (beta) xClC-5 cRNA-injected oocytes presented a very marked pH dependence (inhibition by acid external media) with a pKa value (negative log of the acid dissociation constant) of 5.67. 6. In conclusion, Ibeta-globin may be due to the presence of xClC-5 in the oocyte plasma membrane playing a role as an anion channel whereas Inative may represent an endogenous current induced by xClC-5 cRNA injection. The use of antibodies will facilitate the tissue and subcellular localization of xClC-5 and the identification of its physiological role.
Ackerman,
Hypotonicity activates a native chloride current in Xenopus oocytes.
1994, Pubmed,
Xenbase
Ackerman,
Hypotonicity activates a native chloride current in Xenopus oocytes.
1994,
Pubmed
,
Xenbase
Attali,
The protein IsK is a dual activator of K+ and Cl- channels.
1993,
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
Buyse,
The ubiquitously expressed pICln protein forms homomeric complexes in vitro.
1996,
Pubmed
Coca-Prados,
Association of ClC-3 channel with Cl- transport by human nonpigmented ciliary epithelial cells.
1996,
Pubmed
Duprat,
TASK, a human background K+ channel to sense external pH variations near physiological pH.
1997,
Pubmed
,
Xenbase
Fisher,
Isolation and partial characterization of a chloride channel gene which is expressed in kidney and is a candidate for Dent's disease (an X-linked hereditary nephrolithiasis).
1994,
Pubmed
Fisher,
Cloning and characterization of CLCN5, the human kidney chloride channel gene implicated in Dent disease (an X-linked hereditary nephrolithiasis).
1995,
Pubmed
Gschwentner,
Antisense oligonucleotides suppress cell-volume-induced activation of chloride channels.
1995,
Pubmed
Ishibashi,
Tissue expression of mRNA of chloride channel from MDCK cells and its regulation by protein kinases.
1993,
Pubmed
Jentsch,
Chloride channels: an emerging molecular picture.
1997,
Pubmed
Kozak,
An analysis of vertebrate mRNA sequences: intimations of translational control.
1991,
Pubmed
Krapivinsky,
Molecular characterization of a swelling-induced chloride conductance regulatory protein, pICln.
1994,
Pubmed
,
Xenbase
Krieg,
Functional messenger RNAs are produced by SP6 in vitro transcription of cloned cDNAs.
1984,
Pubmed
,
Xenbase
Lindenthal,
Cloning and functional expression of a ClC Cl- channel from the renal cell line A6.
1997,
Pubmed
,
Xenbase
Lloyd,
A common molecular basis for three inherited kidney stone diseases.
1996,
Pubmed
,
Xenbase
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
Middleton,
Homodimeric architecture of a ClC-type chloride ion channel.
1996,
Pubmed
Miledi,
Chloride current induced by injection of calcium into Xenopus oocytes.
1984,
Pubmed
,
Xenbase
Moorman,
Phospholemman expression induces a hyperpolarization-activated chloride current in Xenopus oocytes.
1992,
Pubmed
,
Xenbase
Paulmichl,
New mammalian chloride channel identified by expression cloning.
1992,
Pubmed
,
Xenbase
Ratcliff,
Activation of osmotically-activated potassium transporters after injection of mRNA from A6 cells in Xenopus oocytes.
1994,
Pubmed
,
Xenbase
Sakamoto,
Identification of a new outwardly rectifying Cl- channel that belongs to a subfamily of the ClC Cl- channels.
1996,
Pubmed
Steinmeyer,
Cloning and functional expression of rat CLC-5, a chloride channel related to kidney disease.
1995,
Pubmed
,
Xenbase
Tzounopoulos,
Induction of endogenous channels by high levels of heterologous membrane proteins in Xenopus oocytes.
1995,
Pubmed
,
Xenbase
van Slegtenhorst,
A gene from the Xp22.3 region shares homology with voltage-gated chloride channels.
1994,
Pubmed
Voets,
The chloride current induced by expression of the protein pICln in Xenopus oocytes differs from the endogenous volume-sensitive chloride current.
1996,
Pubmed
,
Xenbase
