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. 1988 Jun;53(6):877–884. doi: 10.1016/S0006-3495(88)83168-0

Internal motions in proteins and gating kinetics of ionic channels.

P Läuger 1
PMCID: PMC1330268  PMID: 2456104

Abstract

Single-channel current recordings have revealed a complex kinetic behavior of ionic channels. Many channels exhibit closed-time distributions in which long waiting times occur with a much higher frequency than predicted by a simple exponential decay function. In this paper a model for opening-closing transitions that accounts for internal motions in the protein matrix is discussed. The model is based on the notion that the transition between a conductive and a nonconductive state of the channel represents a local process in the protein, such as the movement of a small segment of a peptide chain or the rotation of a single amino-acid residue. When the blocking group moves into the ion pathway, a structural defect is created consisting in a region of loose packing and/or poor hydrogen bonding. By rearrangements of neighboring groups, the defect may migrate within the protein matrix, carrying out a kind of random walk. Once the defect has moved away from the site where it was formed, a transition back to the open state of the channel is possible only when the defect has returned by chance to the original position. The kinetic properties of this model are analyzed by stochastic simulation of defect diffusion in a small domain of the protein. With a suitable choice of domain size and diffusion rate, the model is found to predict closed-time distributions that agree with experimental observations.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Auerbach A., Sachs F. Single-channel currents from acetylcholine receptors in embryonic chick muscle. Kinetic and conductance properties of gaps within bursts. Biophys J. 1984 Jan;45(1):187–198. doi: 10.1016/S0006-3495(84)84147-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Austin R. H., Beeson K. W., Eisenstein L., Frauenfelder H., Gunsalus I. C. Dynamics of ligand binding to myoglobin. Biochemistry. 1975 Dec 2;14(24):5355–5373. doi: 10.1021/bi00695a021. [DOI] [PubMed] [Google Scholar]
  3. Blatz A. L., Magleby K. L. Correcting single channel data for missed events. Biophys J. 1986 May;49(5):967–980. doi: 10.1016/S0006-3495(86)83725-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Clay J. R., DeFelice L. J. Relationship between membrane excitability and single channel open-close kinetics. Biophys J. 1983 May;42(2):151–157. doi: 10.1016/S0006-3495(83)84381-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Colquhoun D., Hawkes A. G. On the stochastic properties of bursts of single ion channel openings and of clusters of bursts. Philos Trans R Soc Lond B Biol Sci. 1982 Dec 24;300(1098):1–59. doi: 10.1098/rstb.1982.0156. [DOI] [PubMed] [Google Scholar]
  6. Colquhoun D., Hawkes A. G. On the stochastic properties of single ion channels. Proc R Soc Lond B Biol Sci. 1981 Mar 6;211(1183):205–235. doi: 10.1098/rspb.1981.0003. [DOI] [PubMed] [Google Scholar]
  7. Colquhoun D., Hawkes A. G. Relaxation and fluctuations of membrane currents that flow through drug-operated channels. Proc R Soc Lond B Biol Sci. 1977 Nov 14;199(1135):231–262. doi: 10.1098/rspb.1977.0137. [DOI] [PubMed] [Google Scholar]
  8. Colquhoun D., Sakmann B. Fast events in single-channel currents activated by acetylcholine and its analogues at the frog muscle end-plate. J Physiol. 1985 Dec;369:501–557. doi: 10.1113/jphysiol.1985.sp015912. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Dionne V. E., Leibowitz M. D. Acetylcholine receptor kinetics. A description from single-channel currents at snake neuromuscular junctions. Biophys J. 1982 Sep;39(3):253–261. doi: 10.1016/S0006-3495(82)84515-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Edmonds D. T. A physical model of sodium channel gating. Eur Biophys J. 1987;14(4):195–201. doi: 10.1007/BF00256352. [DOI] [PubMed] [Google Scholar]
  11. Englander S. W., Kallenbach N. R. Hydrogen exchange and structural dynamics of proteins and nucleic acids. Q Rev Biophys. 1983 Nov;16(4):521–655. doi: 10.1017/s0033583500005217. [DOI] [PubMed] [Google Scholar]
  12. Finkelstein A., Peskin C. S. Some unexpected consequences of a simple physical mechanism for voltage-dependent gating in biological membranes. Biophys J. 1984 Nov;46(5):549–558. doi: 10.1016/S0006-3495(84)84053-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Gurd F. R., Rothgeb T. M. Motions in proteins. Adv Protein Chem. 1979;33:73–165. doi: 10.1016/s0065-3233(08)60459-3. [DOI] [PubMed] [Google Scholar]
  14. Hamill O. P., Marty A., Neher E., Sakmann B., Sigworth F. J. Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches. Pflugers Arch. 1981 Aug;391(2):85–100. doi: 10.1007/BF00656997. [DOI] [PubMed] [Google Scholar]
  15. Horn R., Lange K. Estimating kinetic constants from single channel data. Biophys J. 1983 Aug;43(2):207–223. doi: 10.1016/S0006-3495(83)84341-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Horn R. Statistical methods for model discrimination. Applications to gating kinetics and permeation of the acetylcholine receptor channel. Biophys J. 1987 Feb;51(2):255–263. doi: 10.1016/S0006-3495(87)83331-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Horn R., Vandenberg C. A. Statistical properties of single sodium channels. J Gen Physiol. 1984 Oct;84(4):505–534. doi: 10.1085/jgp.84.4.505. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Klafter J., Shlesinger M. F. On the relationship among three theories of relaxation in disordered systems. Proc Natl Acad Sci U S A. 1986 Feb;83(4):848–851. doi: 10.1073/pnas.83.4.848. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Labarca P., Rice J. A., Fredkin D. R., Montal M. Kinetic analysis of channel gating. Application to the cholinergic receptor channel and the chloride channel from Torpedo californica. Biophys J. 1985 Apr;47(4):469–478. doi: 10.1016/S0006-3495(85)83939-4. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Lakowicz J. R., Freshwater G., Weber G. Nanosecond segmental mobilities of tryptophan residues in proteins observed by lifetime-resolved fluorescence anisotropies. Biophys J. 1980 Oct;32(1):591–601. doi: 10.1016/S0006-3495(80)84992-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Levitt M. Molecular dynamics of native protein. II. Analysis and nature of motion. J Mol Biol. 1983 Aug 15;168(3):621–657. doi: 10.1016/s0022-2836(83)80306-4. [DOI] [PubMed] [Google Scholar]
  22. Liebovitch L. S., Fischbarg J., Koniarek J. P., Todorova I., Wang M. Fractal model of ion-channel kinetics. Biochim Biophys Acta. 1987 Jan 26;896(2):173–180. doi: 10.1016/0005-2736(87)90177-5. [DOI] [PubMed] [Google Scholar]
  23. Magleby K. L., Pallotta B. S. Burst kinetics of single calcium-activated potassium channels in cultured rat muscle. J Physiol. 1983 Nov;344:605–623. doi: 10.1113/jphysiol.1983.sp014958. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Magleby K. L., Pallotta B. S. Calcium dependence of open and shut interval distributions from calcium-activated potassium channels in cultured rat muscle. J Physiol. 1983 Nov;344:585–604. doi: 10.1113/jphysiol.1983.sp014957. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Moczydlowski E., Latorre R. Gating kinetics of Ca2+-activated K+ channels from rat muscle incorporated into planar lipid bilayers. Evidence for two voltage-dependent Ca2+ binding reactions. J Gen Physiol. 1983 Oct;82(4):511–542. doi: 10.1085/jgp.82.4.511. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Munro I., Pecht I., Stryer L. Subnanosecond motions of tryptophan residues in proteins. Proc Natl Acad Sci U S A. 1979 Jan;76(1):56–60. doi: 10.1073/pnas.76.1.56. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Neher E., Sakmann B. Single-channel currents recorded from membrane of denervated frog muscle fibres. Nature. 1976 Apr 29;260(5554):799–802. doi: 10.1038/260799a0. [DOI] [PubMed] [Google Scholar]
  28. Richards F. M. Areas, volumes, packing and protein structure. Annu Rev Biophys Bioeng. 1977;6:151–176. doi: 10.1146/annurev.bb.06.060177.001055. [DOI] [PubMed] [Google Scholar]
  29. Sakmann B., Trube G. Voltage-dependent inactivation of inward-rectifying single-channel currents in the guinea-pig heart cell membrane. J Physiol. 1984 Feb;347:659–683. doi: 10.1113/jphysiol.1984.sp015089. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Shlesinger M. F., Montroll E. W. On the Williams-Watts function of dielectric relaxation. Proc Natl Acad Sci U S A. 1984 Feb;81(4):1280–1283. doi: 10.1073/pnas.81.4.1280. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Sigworth F. J. Open channel noise. II. A test for coupling between current fluctuations and conformational transitions in the acetylcholine receptor. Biophys J. 1986 May;49(5):1041–1046. doi: 10.1016/S0006-3495(86)83732-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Trautmann A. Curare can open and block ionic channels associated with cholinergic receptors. Nature. 1982 Jul 15;298(5871):272–275. doi: 10.1038/298272a0. [DOI] [PubMed] [Google Scholar]
  33. Wagner G. Characterization of the distribution of internal motions in the basic pancreatic trypsin inhibitor using a large number of internal NMR probes. Q Rev Biophys. 1983 Feb;16(1):1–57. doi: 10.1017/s0033583500004911. [DOI] [PubMed] [Google Scholar]
  34. Weber G. Energetics of ligand binding to proteins. Adv Protein Chem. 1975;29:1–83. doi: 10.1016/s0065-3233(08)60410-6. [DOI] [PubMed] [Google Scholar]
  35. Williams R. J. Energy states of proteins, enzymes and membranes. Proc R Soc Lond B Biol Sci. 1978 Mar 22;200(1141):353–389. doi: 10.1098/rspb.1978.0023. [DOI] [PubMed] [Google Scholar]
  36. Woodward C. K., Hilton B. D. Hydrogen exchange kinetics and internal motions in proteins and nucleic acids. Annu Rev Biophys Bioeng. 1979;8:99–127. doi: 10.1146/annurev.bb.08.060179.000531. [DOI] [PubMed] [Google Scholar]
  37. Wüthrich K., Wagner G., Richarz R., Braun W. Correlations between internal mobility and stability of globular proteins. Biophys J. 1980 Oct;32(1):549–560. doi: 10.1016/S0006-3495(80)84989-7. [DOI] [PMC free article] [PubMed] [Google Scholar]

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