Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Removal of phospho-head groups of membrane lipids immobilizes voltage sensors of K+ channels

Abstract

A fundamental question about the gating mechanism of voltage-activated K+ (Kv) channels is how five positively charged voltage-sensing residues1,2 in the fourth transmembrane segment are energetically stabilized, because they operate in a low-dielectric cell membrane. The simplest solution would be to pair them with negative charges3. However, too few negatively charged channel residues are positioned for such a role4,5. Recent studies suggest that some of the channel’s positively charged residues are exposed to cell membrane phospholipids and interact with their head groups5,6,7,8,9. A key question nevertheless remains: is the phospho-head of membrane lipids necessary for the proper function of the voltage sensor itself? Here we show that a given type of Kv channel may interact with several species of phospholipid and that enzymatic removal of their phospho-head creates an insuperable energy barrier for the positively charged voltage sensor to move through the initial gating step(s), thus immobilizing it, and also raises the energy barrier for the downstream step(s).

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: Reaction schemes of lipid hydrolysis and the effect of SMase D on Kv2.1 channels.
Figure 2: Effects of SMase C on Kv2.1, Kir1.1 and a KcsA–Kir2.1 chimaera.
Figure 3: Effect of SMase C and PC-PLC on ionic and gating currents of Shaker channels.
Figure 4: Inhibition of Kv1.3 by SMase C.

References

  1. 1

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

    CAS  Article  Google Scholar 

  2. 2

    Seoh, S. A., Sigg, D., Papazian, D. M. & Bezanilla, F. Voltage-sensing residues in the S2 and S4 segments of the Shaker K+ channel. Neuron 16, 1159–1167 (1996)

    CAS  Article  Google Scholar 

  3. 3

    Armstrong, C. M. Sodium channels and gating currents. Physiol. Rev. 61, 644–683 (1981)

    CAS  Article  Google Scholar 

  4. 4

    Papazian, D. M. et al. Electrostatic interactions of S4 voltage sensor in Shaker K+ channel. Neuron 14, 1293–1301 (1995)

    CAS  Article  Google Scholar 

  5. 5

    Long, S. B., Campbell, E. B. & MacKinnon, R. Voltage sensor of Kv1.2: structural basis of electromechanical coupling. Science 309, 903–908 (2005)

    ADS  CAS  Article  Google Scholar 

  6. 6

    Cuello, L. G., Cortes, D. M. & Perozo, E. Molecular architecture of the KvAP voltage-dependent K+ channel in a lipid bilayer. Science 306, 491–495 (2004)

    ADS  CAS  Article  Google Scholar 

  7. 7

    Freites, J. A., Tobias, D. J., von Heijne, G. & White, S. H. Interface connections of a transmembrane voltage sensor. Proc. Natl Acad. Sci. USA 102, 15059–15064 (2005)

    ADS  CAS  Article  Google Scholar 

  8. 8

    Ramu, Y., Xu, Y. & Lu, Z. Enzymatic activation of voltage-gated potassium channels. Nature 442, 696–699 (2006)

    ADS  CAS  Article  Google Scholar 

  9. 9

    Schmidt, D., Jiang, Q. X. & MacKinnon, R. Phospholipids and the origin of cationic gating charges in voltage sensors. Nature 444, 775–779 (2006)

    ADS  CAS  Article  Google Scholar 

  10. 10

    Glenny, A. T. & Stevens, N. F. Staphylococcal toxins and antitoxins. J. Pathol. Bacteriol. 40, 201–210 (1935)

    CAS  Article  Google Scholar 

  11. 11

    McNamara, P. J., Cuevas, W. A. & Songer, J. G. Toxic phospholipases D of Corynebacterium pseudotuberculosis, C. ulcerans and Arcanobacterium haemolyticum: cloning and sequence homology. Gene 156, 113–118 (1995)

    CAS  Article  Google Scholar 

  12. 12

    Kurpiewski, G., Forrester, L. J., Barrett, J. T. & Campbell, B. J. Platelet aggregation and sphingomyelinase D activity of a purified toxin from the venom of Loxosceles reclusa . Biochim. Biophys. Acta 678, 467–476 (1981)

    CAS  Article  Google Scholar 

  13. 13

    Doery, H. M., Magnusson, B. J., Cheyne, I. M. & Sulasekharam, J. A phospholipase in staphylococcal toxin which hydrolyses sphingomyelin. Nature 198, 1091–1092 (1963)

    ADS  CAS  Article  Google Scholar 

  14. 14

    Read, T. D. et al. The genome sequence of Bacillus anthracis Ames and comparison to closely related bacteria. Nature 423, 81–86 (2003)

    ADS  CAS  Article  Google Scholar 

  15. 15

    Projan, S. J. et al. Nucleotide sequence: the β-hemolysin gene of Staphylococcus aureus . Nucleic Acids Res. 17, 3305 (1989)

    CAS  Article  Google Scholar 

  16. 16

    Kilsdonk, E. P. et al. Cellular cholesterol efflux mediated by cyclodextrins. J. Biol. Chem. 270, 17250–17256 (1995)

    CAS  Article  Google Scholar 

  17. 17

    Lu, Z., Klem, A. M. & Ramu, Y. Ion conduction pore is conserved among potassium channels. Nature 413, 809–813 (2001)

    ADS  CAS  Article  Google Scholar 

  18. 18

    Swartz, K. J. & MacKinnon, R. Mapping the receptor site for hanatoxin, a gating modifier of voltage-dependent K+ channels. Neuron 18, 675–682 (1997)

    CAS  Article  Google Scholar 

  19. 19

    Phillips, L. R. et al. Voltage-sensor activation with a tarantula toxin as cargo. Nature 436, 857–860 (2005)

    ADS  CAS  Article  Google Scholar 

  20. 20

    Swartz, K. J. & MacKinnon, R. Hanatoxin modifies the gating of a voltage-dependent K+ channel through multiple binding sites. Neuron 18, 665–673 (1997)

    CAS  Article  Google Scholar 

  21. 21

    Armstrong, C. M. & Bezanilla, F. Currents related to movement of the gating particles of the sodium channels. Nature 242, 459–461 (1973)

    ADS  CAS  Article  Google Scholar 

  22. 22

    Hoshi, T., Zagotta, W. N. & Aldrich, R. W. Biophysical and molecular mechanisms of Shaker potassium channel inactivation. Science 250, 533–538 (1990)

    ADS  CAS  Article  Google Scholar 

  23. 23

    Kitaguchi, T., Sukhareva, M. & Swartz, K. J. Stabilizing the closed S6 gate in the Shaker Kv channel through modification of a hydrophobic seal. J. Gen. Physiol. 124, 319–332 (2004)

    CAS  Article  Google Scholar 

  24. 24

    Schoppa, N. E., McCormack, K., Tanouye, M. A. & Sigworth, F. J. The size of gating charge in wild-type and mutant Shaker potassium channels. Science 255, 1712–1715 (1992)

    ADS  CAS  Article  Google Scholar 

  25. 25

    Loboda, A. & Armstrong, C. M. Resolving the gating charge movement associated with late transitions in K channel activation. Biophys. J. 81, 905–916 (2001)

    CAS  Article  Google Scholar 

  26. 26

    DeCoursey, T. E., Chandy, K. G., Gupta, S. & Cahalan, M. D. Voltage-gated K+ channels in human T lymphocytes: a role in mitogenesis? Nature 307, 465–468 (1984)

    ADS  CAS  Article  Google Scholar 

  27. 27

    Matteson, D. R. & Deutsch, C. K+ channels in T lymphocytes: a patch clamp study using monoclonal antibody adhesion. Nature 307, 468–471 (1984)

    ADS  CAS  Article  Google Scholar 

  28. 28

    Chandy, K. G. et al. K+ channels as targets for specific immunomodulation. Trends Pharmacol. Sci. 25, 280–289 (2004)

    CAS  Article  Google Scholar 

  29. 29

    Perozo, E., MacKinnon, R., Bezanilla, F. & Stefani, E. Gating currents from a nonconducting mutant reveal open-closed conformations in Shaker K+ channels. Neuron 11, 353–358 (1993)

    CAS  Article  Google Scholar 

  30. 30

    Ramu, Y., Xu, Y. & Lu, Z. Inhibition of CFTR Cl-channel function caused by enzymatic hydrolysis of sphingomyelin. Proc. Natl Acad. Sci. USA 104, 6448–6453 (2007)

    ADS  CAS  Article  Google Scholar 

  31. 31

    Swartz, K. J. & MacKinnon, R. An inhibitor of the Kv2.1 potassium channel isolated from the venom of a Chilean tarantula. Neuron 15, 941–949 (1995)

    CAS  Article  Google Scholar 

Download references

Acknowledgements

We thank S. Billington for sharing SMase D cDNA; C. Deutsch for Kv1.3 cDNA; K. Ho and S. Hebert for Kir1.1; R. Joho for Kv2.1 cDNA; K. Swartz for Shaker-V478W cDNA; C. Armstrong for comments on the manuscript; and P. De Weer for review and discussion of the manuscript. This study was supported by a grant from the National Institute of General Medical Sciences to Z.L.

Author information

Affiliations

Authors

Corresponding author

Correspondence to Zhe Lu.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Xu, Y., Ramu, Y. & Lu, Z. Removal of phospho-head groups of membrane lipids immobilizes voltage sensors of K+ channels. Nature 451, 826–829 (2008). https://doi.org/10.1038/nature06618

Download citation

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing