Retinoic acid controls the bilateral symmetry of somite formation in the mouse embryo.
A striking characteristic of vertebrate embryos is their bilaterally symmetric body plan, which is particularly obvious at the level of the somites and their derivatives such as the vertebral column. Segmentation of the presomitic mesoderm must therefore be tightly coordinated along the left and right embryonic sides. We show that mutant mice defective for retinoic acid synthesis exhibit delayed somite formation on the right side. Asymmetric somite formation correlates with a left-right desynchronization of the segmentation clock oscillations. These data implicate retinoic acid as an endogenous signal that maintains the bilateral synchrony of mesoderm segmentation, and therefore controls bilateral symmetry, in vertebrate embryos.
Vermot
Julien
J
Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP/Collège de France, BP 10142, 67404 Illkirch Cedex, Strasbourg, France. julien@igbmc.u-strasbg.fr
Gallego Llamas
Jabier
J
Fraulob
Valérie
V
Niederreither
Karen
K
Chambon
Pierre
P
Dollé
Pascal
P
D000445:Aldehyde Oxidoreductases / Q000235:genetics / Q000378:metabolism; D000818:Animals; D019521:Body Patterning; D004622:Embryo, Mammalian / Q000378:metabolism*; D047108:Embryonic Development; D051524:Fibroblast Growth Factor 8; D005346:Fibroblast Growth Factors / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D017403:In Situ Hybridization; D008648:Mesoderm / Q000502:physiology*; D051379:Mice; D008822:Mice, Transgenic; D009024:Morphogenesis; D015398:Signal Transduction; D019170:Somites / Q000502:physiology*; D014212:Tretinoin / Q000378:metabolism*
C496457:Fgf8 protein, mouse; D051524:Fibroblast Growth Factor 8; D014212:Tretinoin; D005346:Fibroblast Growth Factors; D000445:Aldehyde Oxidoreductases; C470579:RALDH2 protein, mouse