Force from Lipids

Mechanical stimuli that living cells have to respond to range from thermal molecular agitation to potentially destructive cell swelling caused by osmotic pressure gradients. Mechanosensitivity is the ability of living cells and organisms to respond to external mechanical stimuli, enabling them to interact with their changing environment. During these interactions cellular membranes are a major target for environmental mechanical forces. The molecules that are able to detect and process these mechanical forces into intracellular signals, allowing the cell to respond, are mechanosensitive (MS) ion channels. Although our understanding of the role of MS channels in the physiology of mechanotransduction has recently made significant progress, what makes these channels respond to membrane stresses at the molecular level is not fully understood. In this article, the physical principles underlying interactions between MS channel proteins and the lipid bilayer of cell membranes are discussed.