Voltage-Gated Lipid Ion Channels

PLoS One. 2013 Jun 18;8(6):e65707. doi: 10.1371/journal.pone.0065707. Print 2013.

Abstract

Synthetic lipid membranes can display channel-like ion conduction events even in the absence of proteins. We show here that these events are voltage-gated with a quadratic voltage dependence as expected from electrostatic theory of capacitors. To this end, we recorded channel traces and current histograms in patch-experiments on lipid membranes. We derived a theoretical current-voltage relationship for pores in lipid membranes that describes the experimental data very well when assuming an asymmetric membrane. We determined the equilibrium constant between closed and open state and the open probability as a function of voltage. The voltage-dependence of the lipid pores is found comparable to that of protein channels. Lifetime distributions of open and closed events indicate that the channel open distribution does not follow exponential statistics but rather power law behavior for long open times.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ion Channel Gating*
  • Lipid Bilayers / chemistry*
  • Models, Theoretical
  • Static Electricity

Substances

  • Lipid Bilayers

Grants and funding

A.B. was supported by a grant from the University of Copenhagen. T.H. was supported by the Villum foundation (VKR 022130) - URL:http://veluxfoundations.dk. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.