LBDV, Laboratoire de Biologie du Développement de Villefranche-sur-Mer, Observatoire Océanologique, UMR 7009 CNRS, Université Pierre et Marie Curie, 06230 Villefranche sur Mer, France.
Curr Opin Genet Dev. 2013 Aug;23(4):445-53. doi: 10.1016/j.gde.2013.04.010. Epub 2013 Jun 14.
Recent studies suggest that specification of the dorsal-ventral and left-right axes of the sea urchin embryo relies on Nodal-expressing signalling centres located in the ventral ectoderm and in the archenteron that share striking similarities with vertebrate organising centres. Nodal and its downstream target BMP2/4 pattern all three germ layers along the dorsal-ventral axis, repress neural fates and control morphogenesis of the larva. Moreover, Nodal establishes left-right asymmetry by repressing formation of the adult rudiment and inhibiting germline cells differentiation on the right side, while BMP2/4 promotes expression of mesodermal genes on the left side. These findings provide a framework for future studies and raise new questions regarding the events upstream and downstream of Nodal and BMP signalling during axis formation.
最近的研究表明，海胆胚胎背腹轴和左右轴的特化依赖于位于腹侧外胚层和原肠胚的表达 Nodal 的信号中心，这些信号中心与脊椎动物的组织者中心具有惊人的相似性。Nodal 及其下游靶标 BMP2/4 沿着背腹轴模式化所有三个胚层，抑制神经命运并控制幼虫的形态发生。此外，Nodal 通过抑制成虫原基的形成和抑制右侧生殖细胞的分化来建立左右不对称，而 BMP2/4 则促进左侧中胚层基因的表达。这些发现为未来的研究提供了框架，并提出了关于 Nodal 和 BMP 信号在轴形成过程中上下游事件的新问题。
