In mechanotransduction, mechanical stimuli sensed at the cell surface are propagated through the cytoskeleton and converted into biochemical signals for the modulation of cellular activities. Techniques such as atomic force microscopy and optical tweezers are used to quantify the forces exerted at specific locations on the cellular surface. Now, Xiong et al. report on a plasmonicnanomechanical probe that can simultaneously monitor force transduction events at different sites on the cell surface.
The probe, dubbed a plasmonicnanospring, translates cellular mechanical stimuli into spectral outputs. It consists of two gold nanoparticles attached to the cell surface and to a glass substrate, respectively, and separated by an elastic chain of polyethylene glycol. The nanoparticles give rise to spectral effects that are dependent on their separation, which in turn is a function of the force experienced by the nanoparticle attached to the cell surface. Using the nanosprings, the researchers mapped the dynamics of HeLa cell mechanical responses at several locations following generation of reactive oxygen species after exposure to H2O2. Their results suggest that reactive oxygen species can trigger the mechanotransduction signalling pathway through modulation of the actin filaments in the cytoskeleton.