Coordinated morphogenetic mechanisms shape the vertebrate eye

The molecular bases of vertebrate eye formation have been extensively investigated during the past 20 years. This has resulted in the definition of the backbone of the gene regulatory networks controlling the different steps of eye development and has further highlighted a substantial conservation of these networks among vertebrates. Yet, the precise morphogenetic events allowing the formation of the optic cup from a small group of cells within the anterior neural plate are still poorly understood. It is also unclear if the morphogenetic events leading to eyes of very similar shape are indeed comparable among all vertebrates or if there are any species-specific peculiarities. Improved imaging techniques have enabled to follow how the eye forms in living embryos of a few vertebrate models, whereas the development of organoid cultures has provided fascinating tools to recapitulate tissue morphogenesis of other less accessible species. Here, we will discuss what these advances have taught us about eye morphogenesis, underscoring possible similarities and differences among vertebrates. We will also discuss the contribution of cell shape changes to this process and how morphogenetic and patterning mechanisms integrate to assemble the final architecture of the eye.Work in our labs is supported by the following grants: MINECO BFU2014-53765 and FEDER-2017 to J-RM-M; MINECO, BFU2014-55918-P and Fundación BBVA to FC; MINECO BFU2016-75412-R and FEDER funds and PCIN-2015-176-C02-01/ERA-Net NeuronII and the CIBERER, ISCIII to PB; MINECO BFU2016-81887-REDT and Fundación Ramón Areces-2016 to J-RM-M and PB and an Institutional Grant to the CBMSO from the Fundación Ramón Areces.Peer Reviewe