Using diapause as a platform to understand the biology of dormancy.

Diapause is a fascinating form of biological dormancy that is employed by a broad array of animals as a survival strategy to endure adverse environmental conditions. This unique dormant state can suspend organismal development until a more favourable condition arises, giving the species the greatest chance to survive as a whole. Remarkably, while following the same principle of suspending development, diapause exists in different forms and can occur at various stages before reaching the adult form. Functionally, with multiple evolutionary origins across the animal kingdom, diapause demonstrates the ability to respond to diverse environmental challenges while converging to maintain the same core function of suspending development. At the physiological level, these different diapause states share a similar metabolic adaptation to conserve resources and energy throughout dormancy. Underneath, the same genes have been repeatedly identified as regulators and effectors of diapause at different developmental stages in both invertebrates and vertebrates. This suggests the presence of a conserved molecular programme comprised of the same set of key genes repeatedly reprogrammed and utilized at the core of diapause. The knowledge of diapause from the organismal to molecular levels, together, should serve as a useful window to better understand the biology of dormancy.