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Updated: Jan 5, 2026

Reconstitution of a Kv Channel into Lipid Membranes for Structural and Functional Studies
Published on: July 13, 2013
The influence of membrane bilayer thickness on KcsA channel activity
Karen M Callahan1, Benoit Mondou2, Louis Sasseville1
1From the Département de pharmacologie et physiologie, Faculté de médecine, Université de Montréal , Montréal , Canada.
Abstract:
Atomic resolution structures have provided significant insight into the gating and permeation mechanisms of various ion channels, including potassium channels. However, ion channels may also be regulated by numerous factors, including the physiochemical properties of the membrane in which they are embedded. For example, the matching of the bilayer's hydrophobic region to the hydrophobic external surface of the ion channel is thought to minimize the energetic penalty needed to solvate hydrophobic residues or exposed lipid tails. To understand the molecular basis of such regulation by hydrophobic matching requires examining channels in the presence of the lipid membrane. Here we examine the role of hydrophobic matching in regulating the activity of the model potassium channel, KcsA. 86Rb+ influx assays and single-channel recordings indicate that the non-inactivating E71A KcsA channel is most active in thin bilayers (
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