ROLE OF POU-DOMAIN GENES DURING XENOPUS LAEVIS EMBRYOGENESIS

POU结构域基因家族的几个成员已经被证明是 在发育过程中对组织特异性基因调控很重要。我们有 克隆了两个编码非洲爪哇Pou结构域蛋白的DNA， 属于POU III蛋白类的XLPOU 1和XLPOU 2。两个基因都是 早在胚胎的中性板-神经胚期就有表达。在……里面 成人XLPOU1的表达仅限于皮肤和大脑，而XLPOU 2肾脏和脑组织均有表达。在解剖的胚胎中，两者 XLPOU1和XLPOU2在早期的背前部有表达 尾芽胚胎。与这一定位一致，紫外线治疗，a 使胚胎后部化的条件，大大降低了 XLPOU 1和XLPOU 2。原位杂交研究表明，XLPOU 1 转录产物定位于中性板的前部区域， 神经索。在尾芽阶段的胚胎中，XLPOU 1转录本是 主要分布在大脑和眼睛。有一条清晰的前边界 表达；大脑的最前部区域不会杂交。 表达的后边界，在尾芽期胚胎中很明显，是 在后脑和脊髓的交界处。我们认为XLPOU 1和XLPOU 2，因为它们在胚胎中的定位和早期表达 可能在神经元表型的确定中起重要作用。

Several members of the POU domain gene family have been shown to be important in tissue specific gene regulation during development. We have cloned two DNA's encoding two unique Xenopus laevis POU-domain proteins, XLPOU 1 and XLPOU 2, of the POU III protein class. Both genes are expressed as early as the neutral plate-neurula stage in embryos. In adults, XLPOU 1 expression is restricted to the skin and brain, while XLPOU 2 expression is observed in kidney and brain. In dissected embryos, both XLPOU 1 and XLPOU 2 are expressed in the dorsoanterior portion of the early tailbud embryo. Consistent with this localization, UV treatment, a condition that "posteriorizes" embryos, greatly reduces the expression of XLPOU 1 and XLPOU 2. In situ hybridization studies show that XLPOU 1 transcripts are localized in the anterior region of the neutral plate and nerve cord. In tailbud staged embryos, the XLPOU 1 transcripts are localized mostly in the brain and eye. There is a sharp anterior boundary of expression; the most anterior region of the brain does not hybridize. The posterior boundary of expression, apparent in tailbud stage embryos, is at the junction of the hind-brain and spinal cord. We believe that XLPOU 1 and XLPOU 2, because of their localized and early expression in embryos may play an important role in the specification of neuronal phenotypes.