PATTERN FORMATION 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，称为同源框。 我们有 分离出几个含有同源框的基因，这些基因在 早期爪蟾的发育 我们已经确定了他们的时间和空间 使用北方印迹分析和原位杂交分析表达模式 杂交方法 这些基因中至少有一部分在 原肠胚形成，中胚层发育的关键时期， 神经诱导发生。 这些基因的序列分析 发现其中一些与先前描述的基因同源 在其他物种如老鼠和果蝇中， 介绍了 其中一个新的同源盒基因XDLL- 1与 果蝇Distal-less基因家族 它在胚胎中表达， 骨水泥腺、神经嵴源性内脏弓和前脑。 其 时空表达模式表明该基因参与了 在前脑和颅面发育方面。 除了同源盒之外 我们已经分离出叉头基因家族的新成员。 这个家庭的每个成员都有一个非常有趣的 表达模式，其中至少有一些是癌基因。 第一 爪蟾叉头基因XFKH 1具有许多非常有趣的特征。 它 在胚胎发育的囊胚中期过渡期或之后不久被激活， 胚胎的背侧边缘骨。 在原肠胚早期， 到组织者区域。 在以后的阶段中， 脊索和神经组织区。 此外，它是可诱导的， 在隔离的动物帽中的激活素。 其表达模式及诱导 表明该基因对于早期的 非洲爪蟾胚胎的图案形成。其表达模式和 由激活素诱导表明，该基因具有关键的重要性， 在非洲爪蟾胚胎中形成早期模式。我们已经证明， 基因属于一个更大的家族叉头基因，它，像同源框 基因参与模式形成的不同方面， 分化此外，我们还开展了类似的研究， 斑马鱼胚胎中的模式形成。

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 homeobox. 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 new homeobox genes, the XDLL- 1, is homologous to Drosophila Distal-less gene family. It is expressed in the embryonic cement gland, neural crest derived visceral arches and forebrain. Its temporospatial expression pattern indicates that this gene is involved in forebrain and cranio-facial development. In addition to the homeobox gene family we have isolated new members of the Fork head gene family. The individual members of this family have a highly interesting expression pattern and at least some of them are oncogenes. The first Xenopus Fork head gene XFKH1 has many highly interesting features. It is activated at, or shortly after, the mid-blastula transition in the dorsal marginal bone of the embryo. In early gastrulae it is restricted to the organizer region. At later stages it is expressed in the notochord and neural organizer region. Furthermore, it is inducible by activin in isolated animal caps. Its expression pattern and inducibility by activin suggests that this gene has a critical importance for early pattern formation in Xenopus embryos. Its expression pattern and inducibility by activin suggests that this gene has a critical importance for early pattern formation in Xenopus embryos. We have shown that this gene belongs to a larger family of Fork head genes, which, like homeobox genes are involved in different aspects of pattern formation and cell differentiation. In addition, we have initiated similar research into pattern formation in Zebrafish embryos.