Ubi-p63E promoter sequences drive expression of shg coding sequences with a tension-sensing module inserted between the transmembrane domain and arm-binding site. The tension-sensing module comprises the mTFP1 and Venus fluorescent proteins separated by a nanospring protein domain from spider silk. In the relaxed state, the two fluorophores are close enough to allow FRET. In the relaxed state, the two fluorophores are close enough to allow FRET. The spider silk domain stretches in response to pico Newton forces, reducing FRET.