Application of fluorescence resonance energy transfer and magnetic twisting cytometry to quantify mechanochemical signaling activities in a living cell.

Mechanotransduction is the process by which living cells sense mechanical forces and then convert them into biochemical signaling. Recently, we showed that mechanical stress is transduced from the cell surface to remote cytoplasmic sites within 0.3 seconds, which is at least 40 to 50 times faster than soluble factor-induced signal transduction, and the sites of mechanotransduction colocalize with mechanical stress-induced microtubule displacements. These results suggest that mechanotransduction employs mechanisms different from those of soluble factor-induced signal transduction. Here, we describe a protocol that utilizes fluorescence resonance energy transfer (FRET) and a magnetic twisting cytometry (MTC) device to capture rapid mechanochemical signaling activities in living cells.