Under stress: Changes in stress of the polymer matrix in a protein-polymer hybrid material result in changes of conformation of the protein complex, thus resulting in a damage-reporting material (see picture). The reporter is an engineered chaperonin that covalently entraps a pair of fluorescent proteins. Deformation of the chaperonin leads to a change in fluorophore distance and a change in the fluorescene resonance energy transfer (FRET) signal.