Grau Bové, XavierSubirana, LucieMeister, LydvinaSoubigou, AnaëlNeto, AnaElek, AnamariaNaranjo, SilviaFornas Carreño, OscarGómez Skarmeta, José LuisTena, Juan J.Irimia Martínez, ManuelBertrand, StéphanieSebé-Pedrós, ArnauEscriva, Hector2024-07-162024-07-162024Grau-Bové X, Subirana L, Meister L, Soubigou A, Neto A, Elek A, et al. An amphioxus neurula stage cell atlas supports a complex scenario for the emergence of vertebrate head mesoderm. Nat Commun. 2024 May 29;15(1):4550. DOI: 10.1038/s41467-024-48774-42041-1723http://hdl.handle.net/10230/60759The emergence of new structures can often be linked to the evolution of novel cell types that follows the rewiring of developmental gene regulatory subnetworks. Vertebrates are characterized by a complex body plan compared to the other chordate clades and the question remains of whether and how the emergence of vertebrate morphological innovations can be related to the appearance of new embryonic cell populations. We previously proposed, by studying mesoderm development in the cephalochordate amphioxus, a scenario for the evolution of the vertebrate head mesoderm. To further test this scenario at the cell population level, we used scRNA-seq to construct a cell atlas of the amphioxus neurula, stage at which the main mesodermal compartments are specified. Our data allowed us to validate the presence of a prechordal-plate like territory in amphioxus. Additionally, the transcriptomic profile of somite cell populations supports the homology between specific territories of amphioxus somites and vertebrate cranial/pharyngeal and lateral plate mesoderm. Finally, our work provides evidence that the appearance of the specific mesodermal structures of the vertebrate head was associated to both segregation of pre-existing cell populations, and co-option of new genes for the control of myogenesis.application/pdfeng© The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.info:eu-repo/semantics/articlehttp://dx.doi.org/10.1038/s41467-024-48774-4Cell lineageEvolutionary developmental biologyNeurulationinfo:eu-repo/semantics/openAccess