HOMEOBOXES IN XENOPUS DEVELOPMENT

我们最近发现了一个新的家族， 非洲爪蟾的基因。 我们第一次证明了， 利用果蝇发育控制基因的保守区域， 同源异型盒，有可能识别和分离脊椎动物的基因， 在几个方面与果蝇的基因相似。 此后，类似 其他人已经从许多脊椎动物中分离出了基因，包括 来自人转化细胞的cDNA克隆。 我们已经分离出了最大的 含有同源框的cDNA克隆可在任何脊椎动物中获得， 在原肠胚发育阶段表达。 其中一些基因是 在卵母细胞中表达，这将是我们研究的重点， 因为它们可能是难以捉摸的“细胞质 决定因素”被认为是奠定了卵细胞质的控制， 胚胎分化的最初阶段。 这项建议的目的是确定发展功能 含有爪蟾同源盒的基因。 各种技术将 为了实现这一目标，他们中的许多人利用了现成的 在最早的非洲爪蟾胚胎时期， 发育阶段，在此期间， 胚胎就更难了。

We have recently identified a novel family of developmentally controlled genes in the frog Xenopus laevis. We demonstrated for the first time that, using a conserved region of Drosophila development-controlling genes called the homeobox, it was possible to identify and isolate vertebrate genes that resemble the Drosophila genes in several respects. Since then, similar genes have been isolated by others from a number of vertebrates, including cDNA clones from human transformed cells. We have by now isolated one of the largest collections of homeobox-containing cDNA clones available in any vertebrate, which are expressed at the gastrula stage of development. Some of these genes are expressed maternally in the oocyte and will be the focus of our studies, because they could potentially be examples of the elusive "cytoplasmic determinants" thought to be laid down in egg cytoplasm for the control of the initial steps of embryonic differentiation. The objective of this proposal is to ascertain the developmental function of Xenopus homeobox-containing genes. A variety of techniques will be utilized towards this goal, and many of them take advantage of the ready availability of large amounts of Xenopus embryos during the earliest developmental stages, during which equivalent experiments with mammalian embryos would be much more difficult.