Signalling and cell movement in self-organisation of the developing skin

Embryonc skin produces an array of periodically spaced hair or feather follicles over a period of several days. A number of theories to explain how such repeating patterns can emerge spontaneously in developing tissues have been proposed, with the most influential being Turing’s reaction-diffusion model. However, alternative modes of pattern formation relying on cell movement have also been proposed. I will present evidence from studies on mouse and chicken regarding the integration and relationship between signal-based reaction-diffusion mechanisms and cell-driven mechanisms in periodic patterning of the skin.