Retinoic acid signalling links left-right asymmetric patterning and bilaterally symmetric somitogenesis in the zebrafish embryo

• Published in: Nature Vol. 435; no. 7039; pp. 165 - 171
• Main Authors: Kawakami, Yasuhiko, Raya, Ángel, Belmonte, Juan Carlos Izpisúa, Rodríguez-Esteban, Concepción, Raya, R. Marina
• Format: Journal Article
• Language: English
• Published: London Nature Publishing 12.05.2005; Nature Publishing Group
• Subjects: Acids; Animals; Biological and medical sciences; Body Patterning - physiology; Cilia - physiology; Danio rerio; Embryo, Nonmammalian - embryology; Embryo, Nonmammalian - metabolism; Embryology: invertebrates and vertebrates. Teratology; Embryonic growth stage; Embryos; Fish; Freshwater; Fundamental and applied biological sciences. Psychology; Models, Biological; Molecular Sequence Data; Organogenesis. Fetal development; Organogenesis. Physiological fonctions; Signal Transduction; Signaling; Somites - cytology; Somites - metabolism; Tretinoin - metabolism; Zebrafish - embryology; Zebrafish - genetics; Zebrafish - metabolism; Bilateral symmetry; Embryonic development; Vertebrata; Cyprinidae; Retinoic acid; Pisces
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/nature03512

During embryogenesis, cells are spatially patterned as a result of highly coordinated and stereotyped morphogenetic events. In the vertebrate embryo, information on laterality is conveyed to the node, and subsequently to the lateral plate mesoderm, by a complex cascade of epigenetic and genetic events, eventually leading to a left-right asymmetric body plan. At the same time, the paraxial mesoderm is patterned along the anterior-posterior axis in metameric units, or somites, in a bilaterally symmetric fashion. Here we characterize a cascade of laterality information in the zebrafish embryo and show that blocking the early steps of this cascade (before it reaches the lateral plate mesoderm) results in random left-right asymmetric somitogenesis. We also uncover a mechanism mediated by retinoic acid signalling that is crucial in buffering the influence of the flow of laterality information on the left-right progression of somite formation, and thus in ensuring bilaterally symmetric somitogenesis.