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. 1990 Oct 1;96(4):757–775. doi: 10.1085/jgp.96.4.757

Modification of potassium channel kinetics by histidine-specific reagents

PMCID: PMC2229011  PMID: 2258715

Abstract

We have examined the actions of histidine-specific reagents on potassium channels in squid giant axons. External application of 20-500 microM diethylpyrocarbonate (DEP) slowed the opening of potassium channels with little or no effect on closing rates. Sodium channels were not affected by these low external concentrations of DEP. Internal application of up to 2 mM DEP had no effect on potassium channel kinetics. Steady-state potassium channel currents were reduced in an apparently voltage-dependent manner by external treatment with this reagent. The shape of the instantaneous current-voltage relation was not altered. The voltage-dependent probability of channel opening was shifted toward more positive membrane potentials, thus accounting for the apparent voltage-dependent reduction of steady-state current. Histidine-specific photo-oxidation catalyzed by rose bengal produced alterations in potassium channel properties similar to those observed with DEP. The rate of action of DEP was consistent with a single kinetic class of histidine residues. In contrast to the effects on ionic currents, potassium channel gating currents were not modified by treatment with DEP. These results suggest the existence of a histidyl group (or groups) on the external surface of potassium channels important for a weakly voltage-dependent conformational transition. These effects can be reproduced by a simple kinetic model of potassium channels.

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Selected References

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  1. Alkon D. L. Voltage-dependent calcium and potassium ion conductances: a contingency mechanism for an associative learning model. Science. 1979 Aug 24;205(4408):810–816. doi: 10.1126/science.223244. [DOI] [PubMed] [Google Scholar]
  2. Almers W., Armstrong C. M. Survival of K+ permeability and gating currents in squid axons perfused with K+-free media. J Gen Physiol. 1980 Jan;75(1):61–78. doi: 10.1085/jgp.75.1.61. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Armstrong C. M., Matteson D. R. The role of calcium ions in the closing of K channels. J Gen Physiol. 1986 May;87(5):817–832. doi: 10.1085/jgp.87.5.817. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Baumann A., Grupe A., Ackermann A., Pongs O. Structure of the voltage-dependent potassium channel is highly conserved from Drosophila to vertebrate central nervous systems. EMBO J. 1988 Aug;7(8):2457–2463. doi: 10.1002/j.1460-2075.1988.tb03092.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Begenisich T., Lynch C. Effects of internal divalent cations on voltage-clamped squid axons. J Gen Physiol. 1974 Jun;63(6):675–689. doi: 10.1085/jgp.63.6.675. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Berger S. L. Diethyl pyrocarbonate: an examination of its properties in buffered solutions with a new assay technique. Anal Biochem. 1975 Aug;67(2):428–437. doi: 10.1016/0003-2697(75)90315-2. [DOI] [PubMed] [Google Scholar]
  7. Bezanilla F., Armstrong C. M. Inactivation of the sodium channel. I. Sodium current experiments. J Gen Physiol. 1977 Nov;70(5):549–566. doi: 10.1085/jgp.70.5.549. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Busath D., Begenisich T. Unidirectional sodium and potassium fluxes through the sodium channel of squid giant axons. Biophys J. 1982 Oct;40(1):41–49. doi: 10.1016/S0006-3495(82)84456-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Butler A., Wei A. G., Baker K., Salkoff L. A family of putative potassium channel genes in Drosophila. Science. 1989 Feb 17;243(4893):943–947. doi: 10.1126/science.2493160. [DOI] [PubMed] [Google Scholar]
  10. Carbone E., Fioravanti R., Prestipino G., Wanke E. Action of extracellular pH on Na+ and K+ membrane currents in the giant axon of Loligo vulgaris. J Membr Biol. 1978 Nov 8;43(4):295–315. doi: 10.1007/BF01871693. [DOI] [PubMed] [Google Scholar]
  11. Chandler W. K., Meves H. Sodium and potassium currents in squid axons perfused with fluoride solutions. J Physiol. 1970 Dec;211(3):623–652. doi: 10.1113/jphysiol.1970.sp009297. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Christie M. J., Adelman J. P., Douglass J., North R. A. Expression of a cloned rat brain potassium channel in Xenopus oocytes. Science. 1989 Apr 14;244(4901):221–224. doi: 10.1126/science.2539643. [DOI] [PubMed] [Google Scholar]
  13. Connor J. A., Stevens C. F. Voltage clamp studies of a transient outward membrane current in gastropod neural somata. J Physiol. 1971 Feb;213(1):21–30. doi: 10.1113/jphysiol.1971.sp009365. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Ehrenberg L., Fedorcsak I., Solymosy F. Diethyl pyrocarbonate in nucleic acid research. Prog Nucleic Acid Res Mol Biol. 1976;16:189–262. doi: 10.1016/s0079-6603(08)60758-8. [DOI] [PubMed] [Google Scholar]
  15. FRANKENHAEUSER B., HODGKIN A. L. The after-effects of impulses in the giant nerve fibres of Loligo. J Physiol. 1956 Feb 28;131(2):341–376. doi: 10.1113/jphysiol.1956.sp005467. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Gilly W. F., Armstrong C. M. Divalent cations and the activation kinetics of potassium channels in squid giant axons. J Gen Physiol. 1982 Jun;79(6):965–996. doi: 10.1085/jgp.79.6.965. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Gilly W. F., Armstrong C. M. Gating current and potassium channels in the giant axon of the squid. Biophys J. 1980 Mar;29(3):485–492. doi: 10.1016/S0006-3495(80)85147-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Guy H. R., Seetharamulu P. Molecular model of the action potential sodium channel. Proc Natl Acad Sci U S A. 1986 Jan;83(2):508–512. doi: 10.1073/pnas.83.2.508. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Kamb A., Iverson L. E., Tanouye M. A. Molecular characterization of Shaker, a Drosophila gene that encodes a potassium channel. Cell. 1987 Jul 31;50(3):405–413. doi: 10.1016/0092-8674(87)90494-6. [DOI] [PubMed] [Google Scholar]
  20. Meech R. W., Standen N. B. Potassium activation in Helix aspersa neurones under voltage clamp: a component mediated by calcium influx. J Physiol. 1975 Jul;249(2):211–239. doi: 10.1113/jphysiol.1975.sp011012. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Miles E. W. Modification of histidyl residues in proteins by diethylpyrocarbonate. Methods Enzymol. 1977;47:431–442. doi: 10.1016/0076-6879(77)47043-5. [DOI] [PubMed] [Google Scholar]
  22. Oxford G. S., Wu C. H., Narahashi T. Removal of sodium channel inactivation in squid giant axons by n-bromoacetamide. J Gen Physiol. 1978 Mar;71(3):227–247. doi: 10.1085/jgp.71.3.227. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Quandt F. N. Three kinetically distinct potassium channels in mouse neuroblastoma cells. J Physiol. 1988 Jan;395:401–418. doi: 10.1113/jphysiol.1988.sp016926. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Schwarz T. L., Tempel B. L., Papazian D. M., Jan Y. N., Jan L. Y. Multiple potassium-channel components are produced by alternative splicing at the Shaker locus in Drosophila. Nature. 1988 Jan 14;331(6152):137–142. doi: 10.1038/331137a0. [DOI] [PubMed] [Google Scholar]
  25. Shrager P. Ionic conductance changes in voltage clamped crayfish axons at low pH. J Gen Physiol. 1974 Dec;64(6):666–690. doi: 10.1085/jgp.64.6.666. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Siegelbaum S. A., Camardo J. S., Kandel E. R. Serotonin and cyclic AMP close single K+ channels in Aplysia sensory neurones. Nature. 1982 Sep 30;299(5882):413–417. doi: 10.1038/299413a0. [DOI] [PubMed] [Google Scholar]
  27. Spires S., Begenisich T. Pharmacological and kinetic analysis of K channel gating currents. J Gen Physiol. 1989 Feb;93(2):263–283. doi: 10.1085/jgp.93.2.263. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Stühmer W., Stocker M., Sakmann B., Seeburg P., Baumann A., Grupe A., Pongs O. Potassium channels expressed from rat brain cDNA have delayed rectifier properties. FEBS Lett. 1988 Dec 19;242(1):199–206. doi: 10.1016/0014-5793(88)81015-9. [DOI] [PubMed] [Google Scholar]
  29. Tempel B. L., Jan Y. N., Jan L. Y. Cloning of a probable potassium channel gene from mouse brain. Nature. 1988 Apr 28;332(6167):837–839. doi: 10.1038/332837a0. [DOI] [PubMed] [Google Scholar]
  30. Timpe L. C., Schwarz T. L., Tempel B. L., Papazian D. M., Jan Y. N., Jan L. Y. Expression of functional potassium channels from Shaker cDNA in Xenopus oocytes. Nature. 1988 Jan 14;331(6152):143–145. doi: 10.1038/331143a0. [DOI] [PubMed] [Google Scholar]
  31. White M. M., Bezanilla F. Activation of squid axon K+ channels. Ionic and gating current studies. J Gen Physiol. 1985 Apr;85(4):539–554. doi: 10.1085/jgp.85.4.539. [DOI] [PMC free article] [PubMed] [Google Scholar]

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