Evidence for 2D Solitary Sound Waves in a Lipid Controlled Interface and its Biological Implications

TL;DR

This study reports the first observation of 2D solitary elastic pulses in lipid interfaces, suggesting a potential mechanism for biological communication akin to nerve pulses, with implications for understanding cell signaling.

Contribution

It provides experimental evidence of 2D solitary sound waves in lipid membranes and explores their regulation and biological significance, a novel insight into membrane biophysics.

Findings

Observation of 2D solitary elastic pulses in lipid monolayers

Pulses are excited mechanically and detected by FRET

Interface state influences pulse propagation and characteristics

Abstract

Biological membranes by virtue of their elastic properties should be capable of propagating localized perturbations analogous to sound waves. However, the existence and the possible role of such waves in communication in biology remains unexplored. Here we report the first observations of 2D solitary elastic pulses in lipid interfaces, excited mechanically and detected by FRET. We demonstrate that the nonlinearity near a maximum in the susceptibility of the lipid monolayer results in solitary pulses that also have a threshold for excitation. These experiments clearly demonstrate that the state of the interface regulates the propagation of pulses both qualitatively and quantitatively. We elaborate on the striking similarity of the observed phenomenon to nerve pulse propagation and a thermodynamic basis of cell signaling in general.