Developmental Biology Unit UMR 7009, UPMC University of Paris 06 and Centre National de la Recherche (CNRS), Observatoire Océanologique, Villefranche-sur-Mer, France.
Int Rev Cell Mol Biol. 2012;297:235-64. doi: 10.1016/B978-0-12-394308-8.00006-6.
The completely transparent eggs and embryos of the ascidian Phallusia mammillata are well suited for imaging-based studies of how cell cycle control mechanisms have been integrated into the processes of meiosis, fertilization, and embryonic development. Several cell cycle-related issues that pertain to reproduction and development have been addressed using the ascidian model. For example, how are sperm-triggered calcium oscillations controlled by cell cycle kinases? How is chromosome segregation during meiosis regulated? What processes does the Mos/MAPK signaling cascade control in eggs in addition to CSF-mediated cell cycle arrest? Following fertilization ascidians blastomeres display cell cycle asynchrony, oriented cell division, and unequal cleavage resulting in the formation of a distinctive gastrula composed of precisely 112 cells. Here, we shall summarize these topics and where possible show how the mechanisms identified in ascidians compare to those identified in other organisms.
完全透明的海鞘 Phallusia mammillata 的卵子和胚胎非常适合基于成像的研究，这些研究可以深入了解细胞周期控制机制是如何整合到减数分裂、受精和胚胎发育过程中的。使用海鞘模型已经解决了几个与生殖和发育相关的细胞周期问题。例如，精子触发的钙震荡是如何被细胞周期激酶控制的？减数分裂过程中的染色体分离是如何调控的？Mos/MAPK 信号级联在卵子中除了 CSF 介导的细胞周期阻滞之外还控制哪些过程？受精后，海鞘的胚胎细胞显示出细胞周期不同步、定向细胞分裂和不均匀分裂，导致形成一个由 112 个精确细胞组成的独特原肠胚。在这里，我们将总结这些主题，并尽可能地展示在海鞘中鉴定的机制与在其他生物体中鉴定的机制有何不同。
