Characterization of a Xenopus Homeobox Gene

果蝇的遗传和分子分析都清楚地表明， 表明含有同源框的基因与 参与机构计划的制定。使用分子 来自果蝇的探针，脊椎动物同源盒包含基因 同行被孤立。然而，没有明确的证据表明， 这表明含有同源框的基因在 在脊椎动物中的作用该提案的重点是分析 含有基因的母系表达的同源框的功能， X1Hox 2，在非洲爪蟾中。埃特金博士的初步数据 显示X1Hox 2 mRNA定位于动物大脑半球， 在完全发育卵母细胞中和母体mRNA的破坏 通过注射反义寡脱氧核苷酸， 神经管的特殊缺陷 埃特金博士的假设是 该基因在调节基因中起着重要作用， 非洲爪蟾早期发育中的等级制度。 他会测试这个 通过实现以下具体目标的假设：1） 定义表达的空间和时间模式， X1Hox 2基因原位杂交，RNA酶保护 组织切片中蛋白质的免疫染色， 2）分析该基因在生长过程中是如何调控的 通过检查细胞相互作用的作用， 其表达的自动调节，以及表征 X1Hox 2基因产物可能激活的假定靶基因 在原肠胚阶段和3）确定X1Hox的功能 2基因，包括一种新的组合， 反义寡核苷酸注射，成熟，和 卵母细胞体外受精。 %%% 对该基因及其产物的分析将在 关于同源框如何包含 基因在脊椎动物体型规划的建立中起作用。

Both genetic and molecular analyses of Drosophila have clearly demonstrated that homeobox containing genes are intimately involved in the establishment of the body plan. Using molecular probes from Drosophila the vertebrate homeobox containing gene counterparts were isolated. However, there is no clear evidence demonstrating that the homeobox containing genes play a similar role in vertebrates. This proposal is focused on analyzing the function of a maternally expressed homeobox containing gene, X1Hox 2, in the frog Xenopus laevis. Dr. Etkin's preliminary data show that the X1Hox 2 mRNA is localized in the animal hemisphere in full grown oocytes and that destruction of the maternal mRNA by injection of antisense oligodeoxynucleotides results in a specific defect in the neural tube. Dr. Etkin hypothesis is that this gene plays a fundamental role in the regulatory gene hierarchy in early Xenopus development. He will test this hypothesis by accomplishing the following specific aims: 1) define the spatial and temporal pattern of expression of the X1Hox 2 gene using in situ hybridization, RNase protection assays, and immunostaining of the protein in tissue sections and whole mounts 2) analysis of how this gene is regulated during development by examining the role of cell cell interactions and autoregulation on its expression, as well as characterizing the putative target genes that the X1Hox 2 gene product may activate at the gastrula stage and 3) determine the function of the X1Hox 2 gene using several approaches including a novel combination of antisense oligodeoxynucleotide injection, maturation, and fertilization of oocytes in vitro. %%% The analysis of this gene and its product will be important in the formulation of basic principles of how homeobox containing genes function in the establishment of the vertebrate body plan.