Laguerre Laurent, Ghysen Alain, Dambly-Chaudière Christine
Laboratoire de Neurogénétique, INSERM U881, Montpellier, France.
Dev Dyn. 2009 May;238(5):1042-51. doi: 10.1002/dvdy.21938.
The sense organs of the posterior lateral line system (neuromasts) are formed by a migrating primordium. In zebrafish, the primordium comprises approximately 100 cells at the onset of migration, and has deposited approximately 300 cells by the end of the process. Here, we report localized phases of mitotic activity and of mitotic quiescence within the migrating primordium. Quiescence in the leading region seems associated to the formation of a new prospective neuromast, whereas quiescence in the trailing region follows a wave of mitoses that synchronize trailing cells in G0/G1 phase, anticipating neuromast differentiation. Manipulating the size of the primordium does not lead to changes in the rate of cell proliferation. We also show that two mitoses often take place nearly synchronously in adjacent cells, suggestive of a determinate lineage. We conclude that proliferation in the migrating primordium follows a stereotyped pattern that closely anticipates the normal development of the system.
后侧线系统的感觉器官（神经丘）由一个迁移的原基形成。在斑马鱼中，原基在迁移开始时约由100个细胞组成，到迁移过程结束时已沉积了约300个细胞。在此，我们报告了迁移原基内有丝分裂活动和有丝分裂静止的局部阶段。前端区域的静止似乎与新的预期神经丘的形成有关，而后端区域的静止则跟随有丝分裂波，使后端细胞同步进入G0/G1期，为神经丘分化做准备。操纵原基的大小不会导致细胞增殖速率的变化。我们还表明，相邻细胞中两个有丝分裂常常几乎同步发生，提示有一个确定的谱系。我们得出结论，迁移原基中的增殖遵循一种刻板模式，该模式紧密预期系统的正常发育。
