EXPRESSION OF HOMEO-BOX CONTAINING GENES DURING EARLY XENOPUS DEVELOPMENT

含有同源异型盒的基因是一个基因家族， 果蝇在发育过程中控制图案的形成。 这些基因 编码以序列特异性方式与DNA结合的蛋白质。 他们 含有一个180 bp的保守DNA结构域，称为homebox。 一些基因突变 这些基因的一部分引起“同源异型”转化，其中一部分是基因的一部分。 身体以另一个身体的样子发展。 同源异型盒基因虽然最好 在果蝇的研究中，已经在各种物种中发现了 包括青蛙、老鼠和人。我们已经分离出几个同源框 含有在非洲爪蟾早期发育过程中被激活的基因。 我们 已经确定了他们的时间和空间表达模式， 北方印迹分析和原位杂交。 至少一些这些 基因在原肠胚形成期间表达，这是一个关键的时间段， 中胚层和神经诱导发生的发育。 序列 对这些基因的分析表明，其中一些基因与 先前在其他物种如小鼠和果蝇中描述的基因， 其它的还没有描述。 其中一个同源基因 果蝇的Distal-less基因很可能与肢体 形成和再生。 另一个基因，显示出最高的同源性 小鼠Oct-3基因是一个很好的候选人， 在青蛙早期发育过程中的转录激活因子。 该基因 在卵巢中表达，其RNA优先定位在卵巢中。 胚胎的一半是动物。 该基因可能参与了 外胚层特异性基因转录。 该项目的最终目标是 了解正常发育模式是如何建立的， 在这个过程中起着关键作用。 了解这些 青蛙的发育过程将使我们更好地了解 人类的畸形

Homeobox containing genes are a family of genes which have been shown in Drosophila to control pattern formation during development. These genes encode proteins which bind to DNA in a sequence specific manner. They contain a 180 bp conserved DNA domain called a homebox. Mutations in some of these genes cause "homeotic" transformation, in which one part of the body develops in the likeness of another. Homeobox genes although best studies in Drosophila, have been identified in a variety of species including frogs, mice, and man. We have isolated several homeobox containing genes which are activated during early Xenopus development. We have determined their temporal and spatial expression pattern using Northern blot analysis and in situ hybridization. At least some of these genes are expressed during gastrulation, a critical time period of development at which mesodermal and neural induction takes place. Sequence analysis of these genes revealed that some of them are homologous to previously described genes in other species such as mouse and Drosophila, others have not yet been described. One of the genes which is homologous to the Drosophila Distal-less gene is likely to be involved in limb formation and regeneration. Another gene, which shows a highest homology to the murine Oct-3 gene is a good candidate to be a general transcriptional activator during early frog development. This gene is expressed in the ovary, and its RNA is localized preferentially in the animal half of the embryo. This gene might be involved in establishment of ectoderm specific gene transcription. The ultimate goal of the project is to understand how the normal developmental pattern is established and which of the genes play a critical role in this process. Understanding of these processes in frog will give us a better understanding of developmental malformations in humans.