Mechanosensitive ion channels (MscL) play a critical role in transducing physical stresses at the cell membrane

Cell membrane

The cell membrane or plasma membrane is a biological membrane that separates the interior of all cells from the outside environment. The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells. It basically protects the cell...

 into an electrochemical response.

MscL forms a channel

Ion channel

Ion channels are pore-forming proteins that help establish and control the small voltage gradient across the plasma membrane of cells by allowing the flow of ions down their electrochemical gradient. They are present in the membranes that surround all biological cells...

 organized as a homopentamer, with each subunit containing two transmembrane α-helices. Prokaryotes harbor a large-conductance mechanosensitive channel (gene mscL) that opens in response to stretch forces in the lipid bilayer

Lipid bilayer

The lipid bilayer is a thin membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around cells. The cell membrane of almost all living organisms and many viruses are made of a lipid bilayer, as are the membranes surrounding the cell nucleus...

and participate in the regulation of osmotic pressure within the cell.