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Spectroscopic mapping of voltage sensor movement in the Shaker potassium channel

Abstract

Voltage-gated ion channels underlie the generation of action potentials and trigger neurosecretion and muscle contraction. These channels consist of an inner pore-forming domain, which contains the ion permeation pathway and elements of its gates, together with four voltage-sensing domains, which regulate the gates1,2,3,4,5,6. To understand the mechanism of voltage sensing it is necessary to define the structure and motion of the S4 segment, the portion of each voltage-sensing domain that moves charged residues across the membrane in response to voltage change7,8,9,10,11,12,13,14. We have addressed this problem by using fluorescence resonance energy transfer as a spectroscopic ruler15,16,17 to determine distances between S4s in the Shaker K+ channel in different gating states. Here we provide evidence consistent with S4 being a tilted helix that twists during activation. We propose that helical twist contributes to the movement of charged side chains across the membrane electric field and that it is involved in coupling voltage sensing to gating.

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Figure 1: FRET efficiency by indirect donor lifetime measurement.
Figure 2: Steady-state and dynamic measurement of FRET efficiency change with activation.
Figure 3: Activation motion of S4 can be accounted for by a helical twist of 180°.

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References

  1. Kubo,Y., Baldwin,T. J., Jan,Y. N. & Jan,L. Y. Primary structure and functional expression of a mouse inward rectifier potassium channel. Nature 362, 127–133 (1993).

    Article  ADS  CAS  Google Scholar 

  2. Doyle,D. A. et al. The structure of the potassium channel: molecular basis of K+ conduction and selectivity. Science 280, 69–77 (1998).

    Article  ADS  CAS  Google Scholar 

  3. MacKinnon,R., Cohen,S. L., Kuo,A., Lee,A. & Chait,B. T. Structural conservation in prokaryotic and eukaryotic potassium channels. Science 280, 106–109 (1998).

    Article  ADS  CAS  Google Scholar 

  4. Perozo,E., Cortes,D. M. & Cuello,L. G. Three-dimensional architecture and gating mechanism of a K+ channel studied by EPR spectroscopy. Nature Struct. Biol. 5, 459–469 (1998).

    Article  CAS  Google Scholar 

  5. Perozo,E., Cortes,D. M. & Cuello,L. G. Structural rearrangements underlying K+ channel activation gating. Science 285, 73–78 (1999).

    Article  CAS  Google Scholar 

  6. Yellen,G. The moving parts of voltage-gated ion channels. Q. Rev. Biophys. 31, 239–295 (1998).

    Article  CAS  Google Scholar 

  7. Aggarwal,S. K. & MacKinnon,R. Contribution of the S4 segment to gating charge in the Shaker K+ channel. Neuron 16, 1169–1177 (1996).

    Article  CAS  Google Scholar 

  8. Yang,N. & Horn,R. Evidence for voltage-dependent S4 movement in sodium channels. Neuron 15, 213–218 (1995).

    Article  CAS  Google Scholar 

  9. Larsson,H. P., Baker,O. S., Dhillon,D. S. & Isacoff,E. Y. Transmembrane movement of the Shaker K+ channel S4. Neuron 16, 387–397 (1996).

    Article  CAS  Google Scholar 

  10. Mannuzzu,L. M., Moronne,M. M. & Isacoff,E. Y. Direct physical measure of conformational rearrangement underlying potassium channel gating. Science 271, 213–216 (1996).

    Article  ADS  CAS  Google Scholar 

  11. Yang,N., George,A. L. Jr & Horn,R. Molecular basis of charge movement in voltage-gated sodium channels. Neuron 16, 113–122 (1996).

    Article  Google Scholar 

  12. Yusaf,S. P., Wray,D. & Sivaprasadarao,A. Measurement of the movement of the S4 segment during the activation of a voltage-gated potassium channel. Pflugers Arch. 433, 91–97 (1996).

    Article  CAS  Google Scholar 

  13. Starace,D. M., Stefani,E. & Bezanilla,F. Voltage-dependent proton transport by the voltage sensor of the Shaker K+ channel. Neuron 19, 1319–1327 (1997).

    Article  CAS  Google Scholar 

  14. Baker,O. S., Larsson,H. P., Mannuzzu,L. M. & Isacoff,E. Y. Three transmembrane conformations and sequence-dependent displacement of the S4 domain in Shaker K+ channel gating. Neuron 20, 1283–1294 (1998).

    Article  CAS  Google Scholar 

  15. Stryer,L. Fluorescence energy transfer as a spectroscopic ruler. Annu. Rev. Biochem. 47, 819–846 (1978).

    Article  CAS  Google Scholar 

  16. Cantor,C. R. & Schimmel,P. R. Biophysical Chemistry. Part II: Techniques for the Study of Biological Structure and Function (W. H. Freeman, New York, 1980).

    Google Scholar 

  17. Van Der Meer,B. W., Coker,G. & Chen,S. Y. D. Resonance Energy Transfer: Theory and Data (Wiley, New York, 1994).

  18. Jovin,T. M. & Arndt-Jovin,D. J. in Cell Structure and Function by Microspectrofluorometry (eds Kohen, E., Hirschberg, J. G. & Ploem, J. S.) 99–117 (Academic, New York, 1989).

    Book  Google Scholar 

  19. Isacoff,E. Y., Jan,Y. N. & Jan,L. Y. Evidence for the formation of heteromultimeric potassium channels in Xenopus oocyte. Nature 345, 530–534 (1990).

    Article  ADS  CAS  Google Scholar 

  20. Peled-Zehavi,H., Arkin,I. T., Engelman,D. M. & Shai,Y. Coassembly of synthetic segments of Shaker K+ channel within phospholipid membranes. Biochemistry 35, 6828–6838 (1996).

    Article  CAS  Google Scholar 

  21. Catterall,W. A. Structure and function of voltage-gated ion channels. Annu. Rev. Biochem. 64, 493–531 (1995).

    Article  CAS  Google Scholar 

  22. Durell,S. R., Hao,Y. & Guy,H. R. Structural models of the transmembrane region of voltage-gated and other K+ channels in open, closed, and inactivated conformations. J. Struct. Biol. 121, 263–284 (1998).

    Article  CAS  Google Scholar 

  23. Fretch,G. C., VanDongen,A. M. J., Schuster,G., Brown,A. M. & Joho,R. H. A novel potassium channel with delayed rectifier properties isolated from rat brain by expression cloning. Nature 340, 642–645 (1989).

    Article  ADS  Google Scholar 

  24. Isacoff,E. Y., Jan,Y. N. & Jan,L. Y. Putative receptor for the cytoplasmic inactivation gate in the Shaker K+ channel. Nature 353, 86–90 (1991).

    Article  ADS  CAS  Google Scholar 

  25. Cha,A. & Bezanilla,F. Characterizing voltage-dependent conformational changes in the Shaker K+ channel with fluorescence. Neuron 19, 1127–1140 (1997).

    Article  CAS  Google Scholar 

  26. Dale,R. E., Eisinger,J. & Blumberg,W. E. The orientation freedom of molecular probes. The orientation factor in intramolecular energy transfer. Biophys. J. 26, 161–193 (1979).

    Article  CAS  Google Scholar 

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Acknowledgements

We thank L. Llewelyn for making the linked dimers, and A. Glazer, H. Lecar, J. Ngai, E. Loots, O. Baker, H. P. Larsson, M. Moronne and all the other members of the laboratory for helpful discussions. This work was supported by grants from NIH, American Heart Foundation, CA Affiliate, Department of Energy and Lawrence Berkeley National Laboratory Physical Bioscience Division.

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Correspondence to E. Y. Isacoff.

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Glauner, K., Mannuzzu, L., Gandhi, C. et al. Spectroscopic mapping of voltage sensor movement in the Shaker potassium channel. Nature 402, 813–817 (1999). https://doi.org/10.1038/45561

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