Zhao Chunjie, Guan Wei, Pleasure Samuel J
Department of Neurology, Programs in Neuroscience and Developmental Biology, University of California, UCSF Mission Bay, Box 2722, Rock Hall, 1550 Fourth Street, Room RH-348D, San Francisco, CA 94143-2722, USA.
Brain Res. 2006 Mar 10;1077(1):48-53. doi: 10.1016/j.brainres.2006.01.042. Epub 2006 Feb 20.
Cajal-Retzius (CR) cells are among the earliest born cortical neurons and are required for normal cortical development in rodents and humans; however, their embryonic origin has been controversial. Recent genetic lineage studies and direct visualization of migration of CR cells have demonstrated multiple germinative sources for CR cells on the edges of the developing pallium. We generated transgenic mice using 5' untranslated regions of the Frizzled10 gene in order to mark the cortical hem (the most caudomedial edge of the telencephalic neuroepithelium) and found that these mice faithfully reproduce the previously described expression pattern of Frizzled10 mRNA in the cortical hem, dorsal thalamus and dorsal neural tube. In the cortical hem, expression of LacZ mRNA was confined to the ventricular zone and perdurance of LacZ protein served as lineage marker for CR cells derived from the hem during embryonic life. When these marker mice were crossed with FoxG1 (BF1) mutants, they confirmed the previous finding that in these mice the cortical hem is expanded leading to increased production of CR cells from the medial wall of the cortex.
卡哈尔-雷茨乌斯（CR）细胞是最早生成的皮质神经元之一，对于啮齿动物和人类的正常皮质发育至关重要；然而，它们的胚胎起源一直存在争议。最近的遗传谱系研究以及对CR细胞迁移的直接观察表明，发育中的大脑皮层边缘的CR细胞有多个生发来源。我们利用卷曲蛋白10（Frizzled10）基因的5'非翻译区生成了转基因小鼠，以标记皮质下托（端脑神经上皮最尾内侧边缘），并发现这些小鼠忠实地再现了先前描述的Frizzled10 mRNA在皮质下托、背侧丘脑和背侧神经管中的表达模式。在皮质下托中，LacZ mRNA的表达局限于脑室区，LacZ蛋白的持久性作为胚胎期源自皮质下托的CR细胞的谱系标记。当这些标记小鼠与FoxG1（BF1）突变体杂交时，它们证实了先前的发现，即在这些小鼠中皮质下托扩大，导致来自皮质内侧壁的CR细胞产量增加。
