Posteriorization by FGF, Wnt, and retinoic acid is required for neural crest induction.
Posteriorization by FGF, Wnt, and retinoic acid is required for neural crest induction.
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DOI：
10.1006/dbio.2001.0485
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发表时间：
2002-01
影响因子：
2.7
通讯作者：
S. Villanueva;Álvaro Glavic;P. Ruiz;R. Mayor
中科院分区：
文献类型：
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作者：
S. Villanueva;Álvaro Glavic;P. Ruiz;R. Mayor
神经嵴是在神经板的外侧边缘诱导的独特细胞群。神经嵴不产生于注定成为前脑的神经板前缘。在这里，骨形成蛋白，FGF，Wnt，和视黄酸信号传导在神经嵴诱导的作用进行了分析，通过使用一种检测开发的调查后的神经板。使用前神经板边界和神经嵴的特异性标记，早期神经胚胚胎的后端被证明能够将前神经板边界转化为神经嵴细胞。此外，组织表达前神经板标志物，诱导的BMP活性的中间水平，转化为神经嵴的posteriorizing信号。这种转化是模仿bFGF，Wnt-8，或视黄酸治疗，也抑制了FGF受体，视黄酸受体，和Wnt信号分子的显性负性形式的表达。前神经板边界到神经嵴细胞的转化也实现了在整个胚胎中，通过视黄酸处理或通过使用的视黄酸受体的组成型活性形式。通过分析中胚层标记物的表达和各种移植实验，显示突变型视黄酸受体的表达直接影响外胚层。因此，我们提出了一个两步模型的神经嵴诱导。最初，BMP水平中间所需的神经板和表皮规格诱导神经褶皱与前字符沿着整个神经板边界。随后，该前神经板边界的最后区域通过FGF、Wnt和视黄酸信号的后验活性转化为神经嵴。我们讨论了一个统一的模型，其中侧化和后验信号作为神经嵴诱导所需的相同诱导过程的两个阶段。
The neural crest is a unique cell population induced at the lateral border of the neural plate. Neural crest is not produced at the anterior border of the neural plate, which is fated to become forebrain. Here, the roles of BMPs, FGFs, Wnts, and retinoic acid signaling in neural crest induction were analyzed by using an assay developed for investigating the posteriorization of the neural plate. Using specific markers for the anterior neural plate border and the neural crest, the posterior end of early neurula embryos was shown to be able to transform the anterior neural plate border into neural crest cells. In addition, tissue expressing anterior neural plate markers, induced by an intermediate level of BMP activity, was transformed into neural crest by posteriorizing signals. This transformation was mimicked by bFGF, Wnt-8, or retinoic acid treatment and was also inhibited by expression of the dominant negative forms of the FGF receptor, the retinoic acid receptor, and Wnt signaling molecules. The transformation of the anterior neural plate border into neural crest cells was also achieved in whole embryos, by retinoic acid treatment or by use of a constitutively active form of the retinoic acid receptor. By analyzing the expression of mesodermal markers and various graft experiments, the expression of the mutant retinoic acid receptor was shown to directly affect the ectoderm. We thereby propose a two-step model for neural crest induction. Initially, BMP levels intermediate to those required for neural plate and epidermal specification induce neural folds with an anterior character along the entire neural plate border. Subsequently, the most posterior region of this anterior neural plate border is transformed into the neural crest by the posteriorizing activity of FGFs, Wnts, and retinoic acid signals. We discuss a unifying model where lateralizing and posteriorizing signals are presented as two stages of the same inductive process required for neural crest induction.