Gating of the voltage-dependent chloride channel CIC-0 by the permeant anion
- PMID: 7845466
- DOI: 10.1038/373527a0
Gating of the voltage-dependent chloride channel CIC-0 by the permeant anion
Abstract
Chloride channels of the ClC family are important for the control of membrane excitability, cell volume regulation, and possibly transepithelial transport. Although lacking the typical voltage-sensor found in cation channels, gating of ClC channels is clearly voltage-dependent. For the prototype Torpedo channel ClC-0 (refs 11-15) we now show that channel opening is strongly facilitated by external chloride. Other less permeable anions can substitute for chloride with less efficiency. ClC-0 conductance shows an anomalous mole fraction behaviour with Cl-/NO3- mixtures, suggesting a multi-ion pore. Gating shows a similar anomalous behaviour, tightly linking permeation to gating. Eliminating a positive charge at the cytoplasmic end of domain D12 changes kinetics, concentration dependence and halide selectivity of gating, and alters pore properties such as ion selectivity, single-channel conductance and rectification. Taken together, our results strongly suggest that in these channels voltage-dependent gating is conferred by the permeating ion itself, acting as the gating charge.
Similar articles
-
Two physically distinct pores in the dimeric ClC-0 chloride channel.Nature. 1996 Sep 26;383(6598):340-3. doi: 10.1038/383340a0. Nature. 1996. PMID: 8848047
-
Voltage-dependent electrogenic chloride/proton exchange by endosomal CLC proteins.Nature. 2005 Jul 21;436(7049):424-7. doi: 10.1038/nature03860. Nature. 2005. PMID: 16034422
-
Gating the selectivity filter in ClC chloride channels.Science. 2003 Apr 4;300(5616):108-12. doi: 10.1126/science.1082708. Epub 2003 Mar 20. Science. 2003. PMID: 12649487
-
Structural basis for ion conduction and gating in ClC chloride channels.FEBS Lett. 2004 Apr 30;564(3):229-33. doi: 10.1016/S0014-5793(04)00210-8. FEBS Lett. 2004. PMID: 15111101 Review.
-
Structural insights into chloride and proton-mediated gating of CLC chloride channels.Biochemistry. 2004 Feb 10;43(5):1135-44. doi: 10.1021/bi0359776. Biochemistry. 2004. PMID: 14756549 Review.
Cited by
-
Insights into CLC-0's Slow-Gating from Intracellular Proton Inhibition.Int J Mol Sci. 2024 Jul 16;25(14):7796. doi: 10.3390/ijms25147796. Int J Mol Sci. 2024. PMID: 39063037 Free PMC article.
-
CryoEM structures of the human CLC-2 voltage-gated chloride channel reveal a ball-and-chain gating mechanism.Elife. 2024 Feb 12;12:RP90648. doi: 10.7554/eLife.90648. Elife. 2024. PMID: 38345841 Free PMC article.
-
Structural basis of pH-dependent activation in a CLC transporter.Nat Struct Mol Biol. 2024 Apr;31(4):644-656. doi: 10.1038/s41594-023-01210-5. Epub 2024 Jan 26. Nat Struct Mol Biol. 2024. PMID: 38279055 Free PMC article.
-
Permeant cations modulate pore dynamics and gating of TRPV1 ion channels.J Gen Physiol. 2024 Jan 1;156(1):e202313422. doi: 10.1085/jgp.202313422. Epub 2023 Dec 6. J Gen Physiol. 2024. PMID: 38055192 Free PMC article.
-
ClC-1 Chloride Channel: Inputs on the Structure-Function Relationship of Myotonia Congenita-Causing Mutations.Biomedicines. 2023 Sep 24;11(10):2622. doi: 10.3390/biomedicines11102622. Biomedicines. 2023. PMID: 37892996 Free PMC article. Review.
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Miscellaneous