Abstract
Electric fields promote pore formation in both biological and model membranes. We clamped unmodified planar bilayers at 150-550 mV to monitor transient single pores for a long period of time. We observed fast transitions between different conductance levels reflecting opening and closing of metastable lipid pores. Although mean lifetime of the pores was 3 +/- 0.8 ms (250 mV), some pores remained open for up to approximately 1 s. The mean amplitude of conductance fluctuations (approximately 500 pS) was independent of voltage and close for bilayers of different area (40,000 and 10 microm(2)), indicating the local nature of the conductive defects. The distribution of pore conductance was rather broad (dispersion of approximately 250 pS). Based on the conductance value and its dependence of the ion size, the radius of the average pore was estimated as approximately 1 nm. Short bursts of conductance spikes (opening and closing of pores) were often separated by periods of background conductance. Within the same burst the conductance between spikes was indistinguishable from the background. The mean time interval between spikes in the burst was much smaller than that between adjacent bursts. These data indicate that opening and closing of lipidic pores proceed through some electrically invisible (silent) pre-pores. Similar pre-pore defects and metastable conductive pores might be involved in remodeling of cell membranes in different biologically relevant processes.
Full Text
The Full Text of this article is available as a PDF (114.0 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Akinlaja J., Sachs F. The breakdown of cell membranes by electrical and mechanical stress. Biophys J. 1998 Jul;75(1):247–254. doi: 10.1016/S0006-3495(98)77511-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Antonov V. F., Petrov V. V., Molnar A. A., Predvoditelev D. A., Ivanov A. S. The appearance of single-ion channels in unmodified lipid bilayer membranes at the phase transition temperature. Nature. 1980 Feb 7;283(5747):585–586. doi: 10.1038/283585a0. [DOI] [PubMed] [Google Scholar]
- Basañez G., Nechushtan A., Drozhinin O., Chanturiya A., Choe E., Tutt S., Wood K. A., Hsu Y., Zimmerberg J., Youle R. J. Bax, but not Bcl-xL, decreases the lifetime of planar phospholipid bilayer membranes at subnanomolar concentrations. Proc Natl Acad Sci U S A. 1999 May 11;96(10):5492–5497. doi: 10.1073/pnas.96.10.5492. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bechinger B. The structure, dynamics and orientation of antimicrobial peptides in membranes by multidimensional solid-state NMR spectroscopy. Biochim Biophys Acta. 1999 Dec 15;1462(1-2):157–183. doi: 10.1016/s0005-2736(99)00205-9. [DOI] [PubMed] [Google Scholar]
- Benz R., Beckers F., Zimmermann U. Reversible electrical breakdown of lipid bilayer membranes: a charge-pulse relaxation study. J Membr Biol. 1979 Jul 16;48(2):181–204. doi: 10.1007/BF01872858. [DOI] [PubMed] [Google Scholar]
- Chernomordik L. V., Frolov V. A., Leikina E., Bronk P., Zimmerberg J. The pathway of membrane fusion catalyzed by influenza hemagglutinin: restriction of lipids, hemifusion, and lipidic fusion pore formation. J Cell Biol. 1998 Mar 23;140(6):1369–1382. doi: 10.1083/jcb.140.6.1369. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chernomordik L. V., Sukharev S. I., Popov S. V., Pastushenko V. F., Sokirko A. V., Abidor I. G., Chizmadzhev Y. A. The electrical breakdown of cell and lipid membranes: the similarity of phenomenologies. Biochim Biophys Acta. 1987 Sep 3;902(3):360–373. doi: 10.1016/0005-2736(87)90204-5. [DOI] [PubMed] [Google Scholar]
- Chernomordik L., Chanturiya A. N., Suss-Toby E., Nora E., Zimmerberg J. An amphipathic peptide from the C-terminal region of the human immunodeficiency virus envelope glycoprotein causes pore formation in membranes. J Virol. 1994 Nov;68(11):7115–7123. doi: 10.1128/jvi.68.11.7115-7123.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chernomordik L. Non-bilayer lipids and biological fusion intermediates. Chem Phys Lipids. 1996 Jul 15;81(2):203–213. doi: 10.1016/0009-3084(96)02583-2. [DOI] [PubMed] [Google Scholar]
- Genco I., Gliozzi A., Relini A., Robello M., Scalas E. Electroporation in symmetric and asymmetric membranes. Biochim Biophys Acta. 1993 Jun 18;1149(1):10–18. doi: 10.1016/0005-2736(93)90019-v. [DOI] [PubMed] [Google Scholar]
- Glaser R. W., Leikin S. L., Chernomordik L. V., Pastushenko V. F., Sokirko A. I. Reversible electrical breakdown of lipid bilayers: formation and evolution of pores. Biochim Biophys Acta. 1988 May 24;940(2):275–287. doi: 10.1016/0005-2736(88)90202-7. [DOI] [PubMed] [Google Scholar]
- Krassowska W., Neu J. C. Response of a single cell to an external electric field. Biophys J. 1994 Jun;66(6):1768–1776. doi: 10.1016/S0006-3495(94)80971-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Matsuzaki K., Sugishita K., Ishibe N., Ueha M., Nakata S., Miyajima K., Epand R. M. Relationship of membrane curvature to the formation of pores by magainin 2. Biochemistry. 1998 Aug 25;37(34):11856–11863. doi: 10.1021/bi980539y. [DOI] [PubMed] [Google Scholar]
- Melikyan G. B., Brener S. A., Ok D. C., Cohen F. S. Inner but not outer membrane leaflets control the transition from glycosylphosphatidylinositol-anchored influenza hemagglutinin-induced hemifusion to full fusion. J Cell Biol. 1997 Mar 10;136(5):995–1005. doi: 10.1083/jcb.136.5.995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Miteva M., Andersson M., Karshikoff A., Otting G. Molecular electroporation: a unifying concept for the description of membrane pore formation by antibacterial peptides, exemplified with NK-lysin. FEBS Lett. 1999 Nov 26;462(1-2):155–158. doi: 10.1016/s0014-5793(99)01520-3. [DOI] [PubMed] [Google Scholar]
- Moroz J. D., Nelson P. Dynamically stabilized pores in bilayer membranes. Biophys J. 1997 May;72(5):2211–2216. doi: 10.1016/S0006-3495(97)78864-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nanavati C., Markin V. S., Oberhauser A. F., Fernandez J. M. The exocytotic fusion pore modeled as a lipidic pore. Biophys J. 1992 Oct;63(4):1118–1132. doi: 10.1016/S0006-3495(92)81679-X. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Needham D., Hochmuth R. M. Electro-mechanical permeabilization of lipid vesicles. Role of membrane tension and compressibility. Biophys J. 1989 May;55(5):1001–1009. doi: 10.1016/S0006-3495(89)82898-X. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Neil G. A., Zimmermann U. Electrofusion. Methods Enzymol. 1993;220:174–196. doi: 10.1016/0076-6879(93)20082-e. [DOI] [PubMed] [Google Scholar]
- Neumann E., Schaefer-Ridder M., Wang Y., Hofschneider P. H. Gene transfer into mouse lyoma cells by electroporation in high electric fields. EMBO J. 1982;1(7):841–845. doi: 10.1002/j.1460-2075.1982.tb01257.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ramos C., Teissié J. Tension-voltage relationship in membrane fusion and its implication in exocytosis. FEBS Lett. 2000 Jan 14;465(2-3):141–144. doi: 10.1016/s0014-5793(99)01739-1. [DOI] [PubMed] [Google Scholar]
- Rols M. P., Teissié J. Electropermeabilization of mammalian cells to macromolecules: control by pulse duration. Biophys J. 1998 Sep;75(3):1415–1423. doi: 10.1016/S0006-3495(98)74060-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schmidt A., Wolde M., Thiele C., Fest W., Kratzin H., Podtelejnikov A. V., Witke W., Huttner W. B., Söling H. D. Endophilin I mediates synaptic vesicle formation by transfer of arachidonate to lysophosphatidic acid. Nature. 1999 Sep 9;401(6749):133–141. doi: 10.1038/43613. [DOI] [PubMed] [Google Scholar]
- Soltesz SA, Hammer DA. Lysis of Large Unilamellar Vesicles Induced by Analogs of the Fusion Peptide of Influenza Virus Hemagglutinin. J Colloid Interface Sci. 1997 Feb 15;186(2):399–409. doi: 10.1006/jcis.1996.4670. [DOI] [PubMed] [Google Scholar]
- VanDongen A. M. A new algorithm for idealizing single ion channel data containing multiple unknown conductance levels. Biophys J. 1996 Mar;70(3):1303–1315. doi: 10.1016/S0006-3495(96)79687-X. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wilhelm C., Winterhalter M., Zimmermann U., Benz R. Kinetics of pore size during irreversible electrical breakdown of lipid bilayer membranes. Biophys J. 1993 Jan;64(1):121–128. doi: 10.1016/S0006-3495(93)81346-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Winterhalter M, Helfrich W. Effect of voltage on pores in membranes. Phys Rev A Gen Phys. 1987 Dec 15;36(12):5874–5876. doi: 10.1103/physreva.36.5874. [DOI] [PubMed] [Google Scholar]
- Yafuso M., Kennedy S. J., Freeman A. R. Spontaneous conductance changes, multilevel conductance states and negative differential resistance in oxidized cholesterol black lipid membranes. J Membr Biol. 1974 Jul 12;17(3):201–212. doi: 10.1007/BF01870182. [DOI] [PubMed] [Google Scholar]
- Zhelev D. V., Needham D. Tension-stabilized pores in giant vesicles: determination of pore size and pore line tension. Biochim Biophys Acta. 1993 Apr 8;1147(1):89–104. doi: 10.1016/0005-2736(93)90319-u. [DOI] [PubMed] [Google Scholar]