Cells commonly use lipids to modulate the function of ion channels. The lipid content influences the amplitude of the ionic current and changes the probability of voltage-gated ion channels being in the active or in the resting states.
Experimental findings inferred from a variety of techniques and molecular dynamics studies have revealed a direct interaction between the lipid headgroups and the ion channel residues, suggesting an influence of the local lipid environment on the ion channel function. On the other hand the alteration of the lipids may in principle modify the overall electrostatic environment of the channel, and hence the transmembrane potential, leading to an indirect modulation, i.e. a global effect.
We use simulations to discriminate between the two types of modulation.