REGULATION OF ANTEROPOSTERIOR PATTERNING IN EARLY FROG DEVELOPMENT

POU结构域基因家族已被证明在组织中很重要 发育过程中的特定基因调控。有人提议，波尔 III类转录因子以组合方式作用于建立 大脑中的各种神经元表型。我们正在调查他所扮演的角色 这两个POU III类因子，XlPOU1和XlPOU2，在早期神经中 发展。我们利用XlPOU-1作为一个分子标记 前部神经系统，除谱系图谱外，研究其作用 维甲酸(RA)对胚胎前后构型的影响。我们 观察到随着RA剂量的增加，视网膜节的前结构 大脑逐渐向更多的后脑转化。另外， 高剂量的RA改变了A1系的正常细胞命运 从以神经元为主的表型转变为表皮表型。我们的数据支持 假设外源性类风湿性关节炎或密切相关的衍生品导致 胚胎的后部变形。建立职能角色 对于胚胎发育中的XlPOU2，我们错误表达/过度表达 将人工合成的XlPOU-2mRNA注射到特异性载体中，获得XlPOU-2基因产物 32细胞期胚胎(A1或A4细胞)的卵裂球。由于…… 在这种扰动下，胚胎显示出2度轴，眼睛被融合到 中脑，脑神经IX、X和X的生长异常 XI，以及细胞命运的变化。因此，这些实验表明， XlPOU2在脑发育中的重要作用

The POU domain gene family has been shown to be important in tissue specific gene regulation during development. It has been proposed that POU class III transcription factors act in a combinatorial fashion to establish various neuronal phenotypes in the brain. We are investigating the role of two of these POU class III factors, XlPOU 1 and XlPOU 2, in early neural development. We have used XlPOU 1 as a molecular marker of the developing anterior nervous system, in addition to lineage mapping to study the action of retinoic acid (RA) on anteroposterior patterning in the embryo. We observed that with increasing doses of RA, the anterior structures of the brain were transformed progressively to more posterior ones. Additionally, with high doses of RA the normal cell fate of the A1 lineage was changed from a mostly neuronal phenotype to an epidermal one. Our data support the hypothesis that exogenous RA or a closely related derivative, causes posterior transformations in the embryo. To establish a functional role for XlPOU 2 in embryonic development, we have misexpressed/overexpressed the XlPOU 2 gene product by injecting synthetic XlPOU 2 mRNA into specific blastomeres of the 32-cell stage embryo (A1 or A4 cells). As a result of this perturbation, embryos displayed 2 degree axes, eyes that were fused to the midbrain, abnormalities in the outgrowth of cranial nerves IX, X, and XI, and alterations in cell fate. Thus, these experiments suggest an important role for XlPOU 2 in brain development.