Nadarajah B, Alifragis P, Wong R O L, Parnavelas J G
Department of Anatomy & Developmental Biology, University College London, London WC1E 6BT, UK.
Cereb Cortex. 2003 Jun;13(6):607-11. doi: 10.1093/cercor/13.6.607.
We have used time-lapse imaging of acute cortical slices to study the migration of neurons from their sites of origin to their positions in the developing neocortex. We found that two distinct modes of cell movement, somal translocation and glia-guided locomotion, are responsible for the radial migration of neurons generated in the cortical ventricular zone. The former is the prevalent form of radial movement of the early-born cortical neurons, while the latter is adopted by those generated later in corticogenesis. Interneurons, found to originate in the ganglionic eminence, follow tangential migratory paths to reach the developing cortex. Upon reaching the cortex, these cells seek the ventricular zone using a mode of movement that we have termed 'ventricle-directed migration', before they migrate to their positions in the cortical plate. In addition to these forms of movement, we report here a unique morphological and migratory behavior for a population of cortical neurons. These cells are multipolar in form, and are highly motile in the formation and retraction of their processes. Based on these morphological features, we refer to this type of cells as 'branching cells' and attribute the phenotype to a subset of cortical interneurons.
我们利用急性皮质切片的延时成像技术来研究神经元从其起源部位迁移至发育中的新皮质中所处位置的过程。我们发现，两种不同的细胞运动模式，即体细胞转位和胶质细胞引导的运动，负责皮质脑室区产生的神经元的径向迁移。前者是早期生成的皮质神经元径向运动的普遍形式，而后者则被皮质发生后期生成的神经元所采用。发现中间神经元起源于神经节隆起，它们沿着切线迁移路径到达发育中的皮质。到达皮质后，这些细胞在迁移至皮质板中的位置之前，利用一种我们称为“脑室定向迁移”的运动模式寻找脑室区。除了这些运动形式外，我们在此报告了一群皮质神经元独特的形态和迁移行为。这些细胞呈多极形态，在其突起的形成和回缩过程中具有高度的运动性。基于这些形态特征，我们将这类细胞称为“分支细胞”，并将该表型归因于皮质中间神经元的一个子集。
