PATTERNING OF THE EMBRYONIC AVIAN MIDBRAIN AFTER EXPERIMENTAL INVERSIONS - A POLARIZING ACTIVITY FROM THE ISTHMUS
PATTERNING OF THE EMBRYONIC AVIAN MIDBRAIN AFTER EXPERIMENTAL INVERSIONS - A POLARIZING ACTIVITY FROM THE ISTHMUS
复制标题
DOI：
10.1006/dbio.1994.1120
复制
发表时间：
1994-05-01
影响因子：
2.7
通讯作者：
PUELLES, L
中科院分区：
文献类型：
--
作者：
MARIN, F;PUELLES, L
在1日龄的鸡胚胎的神经管中，以自体移植物或鹌鹑/鸡嵌合体的形式进行了预期中脑的东侧倒位（在某些情况下伴有其他邻近的神经上皮区），包括鼻翼和基底板。这些实验的目的是分析由不同的神经元复合体形成的中脑的组织遗传学的因果关系。对实验胚胎进行处理，以研究产生的细胞结构或研究Engrailed-2基因表达模式。前瞻性中脑的唯一倒置产生了一个正常的中脑。前瞻中脑和前瞻峡小脑组织的关节倒置产生异位的峡小脑复合体和对称的双尾状中脑；此外，前瞻性尾侧间脑被诱导形成极化的峡部间脑表型，以取代前直肠。这些调节过程对翼板和基板都有影响。细胞结构命运的改变发生在Engrailed-2基因梯度表达的相关变化之前。这些结果表明，中脑的极化结构模式是由来自尾侧相邻的峡小脑区域的渐变位置信息调控的，这可能是形态形成因子的来源。(C) 1994学术出版社，Inc.
Rostrocaudal inversions of the prospective midbrain (accompanied in some cases by other adjacent neuroepithelial zones) were performed in the neural tube of a-day-old chick embryos in the form of autografts or quail/chick chimeras, involving both alar and basal plates. These experiments aimed to analyze causally the histogenetic rostrocaudal patterning of the midbrain, formed normally by diverse neuronal complexes. The experimental embryos were processed for study of the resulting cytoarchitecture or for study of the Engrailed-2 gene expression pattern. The exclusive inversion of the prospective midbrain produced a normal midbrain. Joint inversion of prospective midbrain plus the prospective isthmocerebellar tissue gave rise to an ectopic isthmocerebellar complex plus a symmetric double-caudal midbrain; additionally, the prospective caudal diencephalon was induced to form a polarized isthmomesencephalic phenotype in substitution of the pretectum. All these regulation processes affected both the alar and basal plates. The changes in cytoarchitectural fate were preceded by correlated changes in the gradiental expression of the gene Engrailed-2. These results suggest that the polarized structural pattern of the midbrain is regulated by graded positional information derived from the caudally adjacent isthmocerebellar domain, which is probably a source of morphogens. (C) 1994 Academic Press, Inc.