Zaraisky A G, Ecochard V, Kazanskaya O V, Lukyanov S A, Fesenko I V, Duprat A M
Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.
Development. 1995 Nov;121(11):3839-47. doi: 10.1242/dev.121.11.3839.
At the beginning of gastrulation the homeobox-containing gene, XANF-1, is expressed at a low level throughout the animal hemisphere of Xenopus laevis embryos, with a local maximum of expression in the region of the dorsal blastopore lip. By the end of gastrulation expression ceases everywhere except in the most anterior part of the neurectoderm. We have investigated the functions of this gene by microinjecting XANF-1 mRNA in the blastomeres of the 32-cell stage embryo and have observed the following effects. First, microinjections of the mRNA in the animal blastomeres and the blastomeres of the marginal zone elicited massive migration of cells to the interior of the embryo at the early gastrula stage. Second, overexpression of XANF-1 in the ventral marginal zone (VMZ) resulted in the appearance of an additional centre of gastrulation movements and the formation of a secondary axis. In addition we showed that synthetic XANF-1 mRNA was able to cause dorsal-type differentiation in VMZ explants extirpated from the microinjected embryos at the beginning of gastrulation. These results suggest that XANF-1 may control the main functions of cells of the Spemann organizer.
在原肠胚形成开始时，含同源异型框的基因XANF-1在非洲爪蟾胚胎的整个动物半球中低水平表达，在背侧胚孔唇区域表达局部最高。到原肠胚形成结束时，除了神经外胚层最前端部分外，其他各处的表达都停止了。我们通过在32细胞期胚胎的卵裂球中显微注射XANF-1 mRNA来研究该基因的功能，并观察到以下效应。首先，在动物卵裂球和边缘区卵裂球中显微注射mRNA会在原肠胚早期引发大量细胞向胚胎内部迁移。其次，XANF-1在腹侧边缘区（VMZ）的过表达导致出现额外的原肠胚形成运动中心并形成次生轴。此外，我们还表明，合成的XANF-1 mRNA能够在原肠胚形成开始时从显微注射胚胎中取出的VMZ外植体中诱导背侧型分化。这些结果表明，XANF-1可能控制施佩曼组织者细胞的主要功能。
