Blader P, Strähle U
IGBMC, CNRS/INSERM/ULP, Illkirch, 67404, France.
Dev Biol. 1998 Sep 15;201(2):185-201. doi: 10.1006/dbio.1998.8995.
Exposure of vertebrate embryos to ethanol causes cyclopia, but little is known about the underlying mechanisms of this effect. Here we show that cyclopia can be induced in the zebrafish by a short ethanol treatment during early gastrula stages and is accompanied by loss of gene expression characteristic of the ventral aspects of the fore- and midbrain. Interestingly, defects in the expression of ventral brain markers are linked to impaired migration of the prechordal plate mesoderm indicating that the correct position of the prechordal plate mesoderm under the anterior neural plate in the zebrafish embryo is required for specification of the anterior neural midline. Ethanol-induced cyclopia does not, however, impair the induction of anterior neuroectodermal structures in general. Finally, as genes like goosecoid and islet-1 are expressed in prechordal plate cells in a temporal pattern similar to control embryos despite the ectopic position of expressing cells, it appears that regulation of prechordal plate-specific gene expression is largely independent of the final position of the prechordal plate.
脊椎动物胚胎暴露于乙醇会导致独眼畸形，但对于这种效应的潜在机制知之甚少。在此我们表明，在早原肠胚阶段进行短暂的乙醇处理可在斑马鱼中诱导独眼畸形，并且伴随着前脑和中脑腹侧特征性基因表达的丧失。有趣的是，腹侧脑标记物表达的缺陷与脊索前板中胚层迁移受损有关，这表明斑马鱼胚胎中脊索前板中胚层位于前神经板下方的正确位置对于前神经中线的特化是必需的。然而，乙醇诱导的独眼畸形通常不会损害前神经外胚层结构的诱导。最后，尽管表达细胞位置异常，但诸如鹅膏菌素和胰岛-1等基因在脊索前板细胞中的表达时间模式与对照胚胎相似，看来脊索前板特异性基因表达的调控在很大程度上独立于脊索前板的最终位置。
