Characterization of a Xenopus Homeobox Gene

非洲爪蟾同源框基因的表征

• 批准号: 9007410
• 负责人: Laurence Etkin
• 金额: $ 27.5万
• 依托单位: University of Texas, M.D. Anderson Cancer Center
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-08-01 至 1994-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9007410&HistoricalAwards=false
• 关键词: Characterization; Xenopus; Homeobox; Gene

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.

对果蝇的遗传和分子分析都清楚地表明，含有同源异型盒的基因与身体计划的建立密切相关。利用果蝇的分子探针，分离出了含有基因同源盒的脊椎动物。然而，没有明确的证据表明包含基因的同源盒在脊椎动物中起着类似的作用。本研究旨在分析非洲爪蛙母体表达的同源异型盒基因X1Hox2的功能。埃特金博士的初步数据显示，X1Hox 2的mRNA定位于动物大脑半球的成熟卵母细胞中，注射反义寡核苷酸破坏母体的mRNA会导致神经管中的一种特殊缺陷。埃特金博士的假说是，该基因在非洲爪哇早期发育的调控基因体系中发挥着基础性作用。他将通过实现以下具体目标来验证这一假设：1)使用原位杂交、核糖核酸酶保护分析、2)通过检查细胞相互作用和对其表达的自动调节的作用来分析该基因在发育过程中如何调节，以及表征X1Hox2基因产物可能在原肠胚阶段激活的可能的靶基因，以及3)使用包括反义寡核苷酸注射的新组合在内的几种方法来确定X1Hox2基因的功能，卵母细胞的体外成熟和受精。对该基因及其产物的分析在制定含有同源异型盒的基因如何在建立脊椎动物身体计划中发挥作用的基本原则中将是重要的。