Can Cells Signal Each Other Via Sound Waves?
Schneider Group Uncovers New Evidence
By Mark Dwortzan
Scientists have long identified two mechanisms for communication between and within cells—immediate contact, in which proteins within or on cell membranes collide; and diffusion, in which a protein on one cell membrane dispatches particles through the cell that eventually impact another protein or make contact with the same or a neighboring cell. Last spring, Assistant Professor Matthias Schneider (ME) produced research results in Physical Review Letters suggesting a third, fundamentally different, potential mechanism that’s far faster and more efficient—acoustic waves.
Realizing that the inner landscape of individual cells is crowded with a network of two-dimensional ridges, known as “interfaces,” that form a distinct, continuous pathway leading from one end of a cell to another or even connecting multiple cells, Schneider and his collaborators created prototypical interfaces out of lipid molecules derived from a cell membrane, and conducted experiments showing that acoustic waves propagated along these interfaces, just as sound travels through air.
Now, in a recent paper in the Journal of the Royal Society publication Interface, Schneider and Research Associate Shamit Shrivastava have determined that under special physical circumstances, these acoustic waves have the same shape, velocity and amplitude as nerve pulses. Moreover, they are only triggered when the stimulus exceeds a critical value, a phenomena known as “all-or-none excitation” in neurophysiology.
“The similarity between our pulses and those measured by Alan Hodgkin and Andrew Huxley—whose model for nerve pulse propagation earned them the 1963 Nobel Prize in Physiology—is overwhelming,” said Schneider. “A few more tests are necessary to make the call, but if we are right, this will completely change the way we think about neurophysiology and cell communication, introducing a new paradigm based on physical principles from thermodynamics and acoustics as predicted by theoretical physicist Konrad Kaufmann in 1989.”
Both studies suggest that proteins in neighboring cells can “communicate” across the continuous 2D interfaces via acoustic waves, potentially enabling biological activities such as energy consumption, digestion and nerve propagation. Representing a major breakthrough in our understanding of how biological systems might communicate, the research could yield important applications ranging from fundamentally new drug targets to novel approaches for treating neurological disease and engineering artificial organs.