Microtubules, polarity and vertebrate neural tube morphogenesis.
Microtubules, polarity and vertebrate neural tube morphogenesis.
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DOI：
10.1111/joa.12468
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发表时间：
2016-07
影响因子：
2.4
通讯作者：
Copp AJ
中科院分区：
文献类型：
--
作者：
Cearns MD;Escuin S;Alexandre P;Greene ND;Copp AJ
微管是关键的细胞成分，长期以来被认为参与塑造发育中的胚胎的形态发生事件。然而，微管的细胞功能之间的联系，它们对细胞形状和极性的影响以及它们在大规模形态发生中的作用仍然知之甚少。在这里，我们研究了关于产生脊椎动物神经管的两种策略的这些关系：哺乳动物神经板的弯曲和关闭，以及硬骨鱼神经棒的空化。后一过程被比作哺乳动物产生尾侧脊髓的“次级”神经发育。哺乳动物神经管闭合早期，微管沿着神经上皮的顶基轴排列，在功能上参与核迁移，间接影响细胞形状。微管是否在哺乳动物的神经发育中起着其他功能作用尚不清楚。在斑马鱼中，微管通过定位组织中线的顶端蛋白和通过镜像对称的微管装置定向细胞分裂，有助于进一步确定顶端极性蛋白的内侧定位，从而在空化之前确定神经杆中线。Par蛋白与神经上皮中心体定位以及神经杆极化形态发生运动的控制有关。迄今为止，对早期神经系统发育过程中微管功能的了解有限，部分原因是技术无法区分“因”与“果”。未来的发展可能依赖于有选择地损害微管功能的新方法，以研究它们所起的作用。
Microtubules are key cellular components, long known to participate in morphogenetic events that shape the developing embryo. However, the links between the cellular functions of microtubules, their effects on cell shape and polarity and their role in large-scale morphogenesis remain poorly understood. Here, we examine these relationships with respect to two strategies for generating the vertebrate neural tube: bending and closure of the mammalian neural plate, and cavitation of the teleost neural rod. The latter process has been compared to ‘secondary’ neurulation that generates the caudal spinal cord in mammals. Microtubules align along the apico-basal axis of the mammalian neuroepithelium early in neural tube closure, participating functionally in interkinetic nuclear migration which indirectly impacts on cell shape. Whether microtubules play other functional roles in mammalian neurulation remains unclear. In the zebrafish, microtubules are important for defining the neural rod midline prior to its cavitation, both by localizing apical proteins at the tissue midline and by orienting cell division through a mirror-symmetric microtubule apparatus that helps to further define the medial localization of apical polarity proteins. Par proteins have been implicated in centrosome positioning in neuroepithelia as well as in the control of polarized morphogenetic movements in the neural rod. Understanding of microtubule functions during early nervous system development has so far been limited, partly by techniques that fail to distinguish ‘cause’ from ‘effect’. Future developments will likely rely on novel ways to selectively impair microtubule function in order to investigate the roles they play.