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.

  • Article
  • Published:

Physical principles underlying the transduction of bilayer deformation forces during mechanosensitive channel gating

Nature Structural Biology volume 9, pages 696–703 (2002)Cite this article

Abstract

In mechanosensitive (MS) channels, gating is initiated by changes in intra-bilayer pressure profiles originating from bilayer deformation. Here we evaluated two physical mechanisms as triggers of MS channel gating: the energetic cost of protein–bilayer hydrophobic mismatches and the geometric consequences of bilayer intrinsic curvature. Structural changes in the Escherichia coli large MS channel (MscL) were studied under nominally zero transbilayer pressures using both patch clamp and EPR spectroscopic approaches. Changes in membrane intrinsic curvature induced by the external addition of lysophosphatidylcholine (LPC) generated massive spectroscopic changes in the narrow constriction that forms the channel 'gate', trapping the channel in the fully open state. Hydrophobic mismatch alone was unable to open the channel, but decreasing bilayer thickness lowered MscL activation energy, stabilizing a structurally distinct closed channel intermediate. We propose that the mechanism of mechanotransduction in MS channels is defined by both local and global asymmetries in the transbilayer pressure profile at the lipid–protein interface.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: MscL gating is triggered by transbilayer pressure gradients and transduced via intra-bilayer tension changes.
Figure 2: Hydrophobic surface matching stabilizes intermediate conformations but does not fully open MscL.
Figure 3: Hydrophobic mismatch induces conformational rearrangements of MscL gate.
Figure 4: Stabilization of open MscL with mixtures of PC–LPC.
Figure 5: Mixtures of PC–LPC induce massive conformational changes in MscL
Figure 6: Asymmetries in the intra-bilayer tension gradient are required for MscL gating.
Figure 7: A model depicting the evolution of structurally distinct conformations during MscL gating.

Similar content being viewed by others

References

  1. Sukharev, S.I., Blount, P., Martinac, B. & Kung, C. Mechanosensitive channels of Escherichia coli: the MscL gene, protein, and activities. Annu. Rev. Physiol. 59, 633–657 (1997).

    Article  CAS  Google Scholar 

  2. Booth, I.R. & Louis, P. Managing hypoosmotic stress: aquaporins and mechanosensitive channels in Escherichia coli. Curr. Opin. Microbiol. 2, 166–169 (1999).

    Article  CAS  Google Scholar 

  3. Wood, J.M. Osmosensing by bacteria: signals and membrane-based sensors. Microbiol. Mol. Biol. Rev. 63, 230–262 (1999).

    CAS  PubMed  PubMed Central  Google Scholar 

  4. Hamill, O.P. & Martinac, B. Molecular basis of mechanotransduction in living cells. Physiol. Rev. 81, 685–740 (2001).

    Article  CAS  Google Scholar 

  5. Martinac, B. Mechanosensitive channels in prokaryotes. Cell. Physiol. Biochem. 11, 61–76 (2001).

    Article  CAS  Google Scholar 

  6. Martinac, B., Buechner, M., Delcour, A.H., Adler, J. & Kung, C. Pressure-sensitive ion channel in Escherichia coli. Proc. Natl. Acad. Sci. USA 84, 2297–2301 (1987).

    Article  CAS  Google Scholar 

  7. Sukharev, S.I., Martinac, B., Arshavsky, V.Y. & Kung, C. Two types of mechanosensitive channels in the Escherichia coli cell envelope: solubilization and functional reconstitution. Biophys. J. 65, 177–183 (1993).

    Article  CAS  Google Scholar 

  8. Sukharev, S.I., Blount, P., Martinac, B., Blattner, F.R. & Kung, C. A large-conductance mechanosensitive channel in E. coli encoded by MscL alone. Nature 368, 265–268 (1994).

    Article  CAS  Google Scholar 

  9. Chang, G., Spencer, R.H., Lee, A.T., Barclay, M.T. & Rees, D.C. Structure of the MscL homolog from Mycobacterium tuberculosis: a gated mechanosensitive ion channel. Science 282, 2220–2226 (1998).

    Article  CAS  Google Scholar 

  10. Berrier, C., Coulombe, A., Houssin, C. & Ghazi, A. A patch-clamp study of ion channels of inner and outer membranes and of contact zones of E. coli, fused into giant liposomes. Pressure-activated channels are localized in the inner membrane. FEBS Lett. 259, 27–32 (1989).

    Article  CAS  Google Scholar 

  11. Cantor, R.S. Lateral pressures in cell membranes: a mechanism for modulation of protein function. J. Phys. Chem. B 101, 1723–1725 (1997).

    Article  CAS  Google Scholar 

  12. Cantor, R.S. Lipid composition and the lateral pressure profile in bilayers. Biophys J. 76, 2625–2639 (1999).

    Article  CAS  Google Scholar 

  13. Mouritsen, O.G. & Bloom, M. Mattress model of lipid-protein interactions in membranes. Biophys. J. 46, 141–153 (1984).

    Article  CAS  Google Scholar 

  14. Gruner, S. in Biologically Inspired Physics (ed. Peliti, L.) 127–135 (Plenum, New York; 1991).

    Book  Google Scholar 

  15. Israelachvili, J. Intermolecular and Surface Forces (Academic Press, New York; 1992).

  16. Killian, J.A. Hydrophobic mismatch between proteins and lipids in membranes. Biochim. Biophys. Acta 1376, 401–415 (1998).

    Article  CAS  Google Scholar 

  17. Cornea, R.L. & Thomas, D.D. Effects of membrane thickness on the molecular dynamics and enzymatic activity of reconstituted Ca-ATPase. Biochemistry 33, 2912–2920 (1994).

    Article  CAS  Google Scholar 

  18. Galbraith, T.P. & Wallace, B.A. Phospholipid chain length alters the equilibrium between pore and channel forms of gramicidin. Faraday Discuss. 111, 159–164 (1998).

    Article  CAS  Google Scholar 

  19. Lundbaek, J.A. & Andersen, O.S. Spring constants for channel-induced lipid bilayer deformations. Estimates using gramicidin channels. Biophys. J. 76, 889–895 (1999).

    Article  CAS  Google Scholar 

  20. Dumas, F., Tocanne, J.F., Leblanc, G. & Lebrun, M.C. Consequences of hydrophobic mismatch between lipids and melibiose permease on melibiose transport. Biochemistry 39, 4846–4854 (2000).

    Article  CAS  Google Scholar 

  21. Lewis, B.A. & Engelman, D.M. Lipid bilayer thickness varies linearly with acyl chain length in fluid phosphatidylcholine vesicles. J. Mol. Biol. 166, 211–217 (1983).

    Article  CAS  Google Scholar 

  22. Gruner, S.M. Intrinsic curvature hypothesis for biomembrane lipid composition: a role for nonbilayer lipids. Proc. Natl. Acad. Sci. USA 82, 3665–3669 (1985).

    Article  CAS  Google Scholar 

  23. Martinac, B., Adler, J. & Kung, C. Mechanosensitive ion channels of E. coli activated by amphipaths. Nature 348, 261–263 (1990).

    Article  CAS  Google Scholar 

  24. Lundbaek, J.A. & Andersen, O.S. Lysophospholipids modulate channel function by altering the mechanical properties of lipid bilayers. J. Gen. Physiol. 104, 645–673 (1994).

    Article  CAS  Google Scholar 

  25. Casado, M. & Ascher, P. Opposite modulation of NMDA receptors by lysophospholipids and arachidonic acid: common features with mechanosensitivity. J. Physiol. 513, 317–330 (1998).

    Article  CAS  Google Scholar 

  26. Maingret, F., Patel, A.J., Lesage, F., Lazdunski, M. & Honoré, E. Lysophospholipids open the two-pore domain mechano-gated K+ channels TREK-1 and TRAAK. J. Biol. Chem. 275, 10128–10133 (2000).

    Article  CAS  Google Scholar 

  27. Mandersloot, J.G., Reman, F.C., Van Deenen, L.L. & De Gier, J. Barrier properties of lecithin/lysolecithin mixtures. Biochim. Biophys. Acta 382, 22–26 (1975).

    Article  CAS  Google Scholar 

  28. Hubbell, W.L., Gross, A., Langen, R. & Lietzow, M.A. Recent advances in site-directed spin labeling of proteins. Curr. Opin. Struct. Biol. 8, 649–656 (1998).

    Article  CAS  Google Scholar 

  29. Hubbell, W.L., Cafiso, D.S. & Altenbach, C. Identifying conformational changes with site-directed spin labeling. Nature Struct. Biol. 7, 735–739 (2000).

    Article  CAS  Google Scholar 

  30. Mchaourab, H. & Perozo, E. in Biological Magnetic Resonance Vol. 19 (ed. S. Eaton, G.E. & Berliner, L.) 155–218 (Kluwer-Plenum, New York; 2000).

    Google Scholar 

  31. Perozo, E., Kloda, A., Cortes, D.M. & Martinac, B. Site-directed spin-labeling analysis of reconstituted MscL in the closed state. J. Gen. Physiol. 118, 193–206 (2001).

    Article  CAS  Google Scholar 

  32. Ou, X., Blount, P., Hoffman, R.J. & Kung, C. One face of a transmembrane helix is crucial in mechanosensitive channel gating. Proc. Natl. Acad. Sci. USA 95, 11471–11475 (1998).

    Article  CAS  Google Scholar 

  33. Sukharev, S., Betanzos, M., Chiang, C.-S. & Guy, H.R. The gating mechanism of the large mechanosensitive channel MscL. Nature 409, 720–724 (2001).

    Article  CAS  Google Scholar 

  34. Sukharev, S., Durell, S.R. & Guy, H.R. Structural models of the MscL gating mechanism. Biophys. J. 81, 917–936 (2001).

    Article  CAS  Google Scholar 

  35. Gullingsrud, J., Kosztin, D. & Schulten, K. Structural determinants of MscL gating studied by molecular dynamics simulations. Biophys. J. 80, 2074–2081 (2001).

    Article  CAS  Google Scholar 

  36. Sukharev, S.I., Sigurdson, W.J., Kung, C. & Sachs, F. Energetic and spatial parameters for gating of the bacterial large conductance mechanosensitive channel, MscL. J. Gen. Physiol. 113, 525–540 (1999).

    Article  CAS  Google Scholar 

  37. Delcour, A.H., Martinac, B., Adler, J. & Kung, C. Modified reconstitution method used in patch-clamp studies of Escherichia coli ion channels. Biophys. J. 56, 631–636 (1989).

    Article  CAS  Google Scholar 

  38. Häse, C.C., Le Dain, A.C. & Martinac, B. Purification and functional reconstitution of the recombinant large mechanosensitive ion channel (MscL) of Escherichia coli. J. Biol. Chem. 270, 18329–18334 (1995).

    Article  Google Scholar 

  39. Cruickshank, C.C., Minchin, R.F., Le Dain, A.C. & Martinac, B. Estimation of the pore size of the large-conductance mechanosensitive ion channel of Escherichia coli. Biophys. J. 73, 1925–1931 (1997).

    Article  CAS  Google Scholar 

  40. Cortes, D.M., Cuello, L.G. & Perozo, E. Molecular architecture of full-length KcsA: role of cytoplasmic domains in ion permeation and activation gating. J. Gen. Physiol. 117, 165–180 (2001).

    Article  CAS  Google Scholar 

  41. Mchaourab, H.S., Lietzow, M.A., Hideg, K. & Hubbell, W.L. Motion of spin-labeled side chains in T4 lysozyme. Correlation with protein structure and dynamics. Biochemistry 35, 7692–7704 (1996).

    Article  CAS  Google Scholar 

  42. Columbus, L., Kálai, T., Jekö, J., Hideg, K. & Hubbell, W.L. Molecular motion of spin labeled side chains in α-helices: analysis by variation of side chain structure. Biochemistry 40, 3828–3846 (2001).

    Article  CAS  Google Scholar 

  43. 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 

Download references

Acknowledgements

We thank T. Thompsom and R. Biltonen for insightful discussions and C. Ptak for critically reading the manuscript. Support and encouragement from S. Mochel is greatly appreciated. This work was supported in part by NIH (E.P.) and the McKnight endowment fund for neuroscience (E.P.), the Australian Research Council (B.M.) and the Australian Academy of Science (Scientific Visit Award to B.M).

Author information

Authors and Affiliations

  1. Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, 22906, Virginia, USA

    Eduardo Perozo & D. Marien Cortes

  2. Department of Pharmacology, Queen Elisabeth II Medical Center, University of Western Australia, Crawley, 6009, Western Australia, Australia

    Anna Kloda & Boris Martinac

Authors
  1. Eduardo Perozo
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Anna Kloda
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. D. Marien Cortes
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Boris Martinac
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Eduardo Perozo.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Perozo, E., Kloda, A., Cortes, D. et al. Physical principles underlying the transduction of bilayer deformation forces during mechanosensitive channel gating. Nat Struct Mol Biol 9, 696–703 (2002). https://doi.org/10.1038/nsb827

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nsb827

This article is cited by

Search

Advanced 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