ThePax6master control gene initiates spontaneous retinal development via a self-organising Turing network
AbstractUnderstanding how complex organ systems are assembled from simple embryonic tissues is a major challenge. Across the animal kingdom a great diversity of visual organs are initiated by a ‘master control gene’ calledPax6, which is both necessary and sufficient for eye development1–6. Yet precisely howPax6achieves this deeply homologous function is poorly understood. Here we show that vertebratePax6interacts with a pair of morphogen-coding genes,Tgfb2andFst, to form a putative Turing network7, which we have computationally modelled. Computer simulations suggest that this gene network is sufficient to spontaneously polarise the developing retina, establishing the eye’s first organisational axis and prefiguring its further development. Our findings reveal how retinal self-organisation may be initiated independent of the highly ordered tissue interactions that help to assemble the eyein vivo. These results help to explain how stem cell aggregates spontaneously self-organise into functional eye-cupsin vitro8. We anticipate these findings will help to underpin retinal organoid technology, which holds much promise as a platform for disease modelling, drug development and regenerative therapies.