Leon, AnthonySubirana, LucieMagre, KevinCases, IldefonsoTena, Juan J.Irimia Martínez, ManuelGómez Skarmeta, José LuisEscriva, HectorBertrand, Stéphanie2022-05-302022-05-302022Leon A, Subirana L, Magre K, Cases I, Tena JJ, Irimia M et al. Gene regulatory networks of epidermal and neural fate choice in a chordate. Mol Biol Evol. 2022 Apr 11;39(4):msac055. DOI:10.1093/molbev/msac0550737-4038http://hdl.handle.net/10230/53314Neurons are a highly specialized cell type only found in metazoans. They can be scattered throughout the body or grouped together, forming ganglia or nerve cords. During embryogenesis, centralized nervous systems develop from the ectoderm, which also forms the epidermis. How pluripotent ectodermal cells are directed toward neural or epidermal fates, and to which extent this process is shared among different animal lineages, are still open questions. Here, by using micromere explants, we were able to define in silico the putative gene regulatory networks (GRNs) underlying the first steps of the epidermis and the central nervous system formation in the cephalochordate amphioxus. We propose that although the signal triggering neural induction in amphioxus (i.e., Nodal) is different from vertebrates, the main transcription factors implicated in this process are conserved. Moreover, our data reveal that transcription factors of the neural program seem to not only activate neural genes but also to potentially have direct inputs into the epidermal GRN, suggesting that the Nodal signal might also contribute to neural fate commitment by repressing the epidermal program. Our functional data on whole embryos support this result and highlight the complex interactions among the transcription factors activated by the signaling pathways that drive ectodermal cell fate choice in chordates.application/pdfeng© Anthony Leon et al. 2022. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (https://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly citedGenèticaEpidermisSistema nerviós centralinfo:eu-repo/semantics/articlehttp://dx.doi.org/10.1093/molbev/msac055info:eu-repo/semantics/openAccess