Arenzana F J, Santos-Ledo A, Porteros A, Aijón J, Velasco A, Lara J M, Arévalo R
Grupo de Neurobiología del Desarrollo-GNDe, Hospital Nacional de Parapléjicos, Finca La Peraleda s/n, Toledo, E-45071, Spain.
Int J Dev Neurosci. 2011 Jun;29(4):441-9. doi: 10.1016/j.ijdevneu.2011.02.008. Epub 2011 Mar 8.
During visual system morphogenesis, several cell populations arise at different time points correlating with the expression of specific molecular markers We have analysed the distribution pattern of three molecular markers (zn-1, calretinin and glial fibrillary acidic protein) which are involved in the development of zebrafish retina and optic tectum. zn-1 is a neural antigen expressed in the developing zebrafish central nervous system. Calretinin is the first calcium-binding protein expressed in the central nervous system of vertebrates and it is widely distributed in different neuronal populations of vertebrate retina, being a valuable marker for its early and late development. Glial fibrillary acidic protein (GFAP), which is an astroglial marker, is a useful tool for characterising the glial environment in which the optic axons develop. We describe the expression profile changes in these three markers throughout the zebrafish lifespan with special attention to ganglion cells and their projections. zn-1 is expressed in the first postmitotic ganglion cells of the retina. Calretinin is observed in the ganglion and amacrine cells of the retina in neurons of different tectal bands and in axons of retinofugal projections. GFAP is localised in the endfeet of Müller cells and in radial processes of the optic tectum after hatching. A transient expression of GFAP in the optic nerve, coinciding with the arrival of the first calretinin-immunoreactive optic axons, is observed. As axonal growth occurs in these regions of the zebrafish visual pathway (retina and optic tectum) throughout the lifespan, a relationship between GFAP expression and the correct arrangement of the first optic axons may exist. In conclusion we provide valuable neuroanatomical data about the best characterised sensorial pathway to be used in further studies such as teratology and toxicology.
在视觉系统形态发生过程中，几个细胞群体在不同时间点出现，这与特定分子标记的表达相关。我们分析了三种参与斑马鱼视网膜和视顶盖发育的分子标记（zn-1、钙视网膜蛋白和胶质纤维酸性蛋白）的分布模式。zn-1是一种在发育中的斑马鱼中枢神经系统中表达的神经抗原。钙视网膜蛋白是脊椎动物中枢神经系统中表达的首个钙结合蛋白，它广泛分布于脊椎动物视网膜的不同神经元群体中，是其早期和晚期发育的重要标记。胶质纤维酸性蛋白（GFAP）是一种星形胶质细胞标记物，是表征视神经轴突发育所处胶质环境的有用工具。我们描述了这三种标记在斑马鱼整个生命周期中的表达谱变化，特别关注神经节细胞及其投射。zn-1在视网膜的首批有丝分裂后神经节细胞中表达。在视网膜的神经节细胞和无长突细胞、不同视顶盖带的神经元以及视网膜外投射轴突中观察到钙视网膜蛋白。孵化后，GFAP定位于穆勒细胞的终足和视顶盖的放射状突起中。观察到GFAP在视神经中有短暂表达，这与首批钙视网膜蛋白免疫反应性视神经轴突的到达时间一致。由于在斑马鱼视觉通路的这些区域（视网膜和视顶盖）整个生命周期中都发生轴突生长，GFAP表达与首批视神经轴突的正确排列之间可能存在关联。总之，我们提供了有价值的神经解剖学数据，这些数据可用于诸如畸形学和毒理学等进一步研究中最具特征的感觉通路。
