Plays a central role in insect flight by providing low stiffness, high strain and efficient energy storage. Expressed at pupal stage only. Its strong elasticity suggests that it may be used for industrial and pharmaceutical applications. Recombinant protein can be cast into a rubber-like biomaterial by rapid photochemical cross-linking. The resilience (recovery after deformation) of cross-linked recombinant resilin exceeds that of unfilled synthetic polybutadiene, a high resilience rubber.