Smith R C
J Embryol Exp Morphol. 1986 Jun;95:15-35.
The patterns of proteins synthesized in animal and vegetal regions of Xenopus oocytes, eggs and embryos were examined by 2D gel electrophoresis. In oocytes and eggs, the only proteins synthesized asymmetrically along the animal-vegetal axis were a small number of proteins synthesized predominantly in the vegetal hemisphere. At the cleavage stage there were a total of four proteins synthesized unevenly in animal and vegetal regions: three synthesized predominantly in the vegetal hemisphere and one synthesized predominantly in the animal hemisphere. By the gastrula stage, when maternal messages have largely been replaced by embryonic transcripts, the number of differences in proteins synthesized in the animal-derived ectoderm and mesoderm, and the vegetal-derived endoderm started to increase rapidly with time of development with many more animal-characteristic proteins than vegetal-characteristic proteins appearing. Comparison of protein synthesis patterns with those obtained when extracted RNA was translated in vitro and run on 2D gels, showed that the asymmetry in protein synthesis along the animal-vegetal axis in the oocyte and early embryo reflected directly the distribution of their mRNAs along the axis. There was no evidence for localized 'masked' abundant messages along the animal-vegetal axis of oocytes and cleavage embryos.
通过二维凝胶电泳检测了非洲爪蟾卵母细胞、卵子和胚胎的动物极和植物极区域合成的蛋白质模式。在卵母细胞和卵子中，沿动物 - 植物轴不对称合成的唯一蛋白质是少数主要在植物半球合成的蛋白质。在卵裂阶段，动物极和植物极区域共有四种蛋白质合成不均匀：三种主要在植物半球合成，一种主要在动物半球合成。到原肠胚阶段，当母体信息大部分已被胚胎转录本取代时，动物来源的外胚层和中胚层以及植物来源的内胚层中合成的蛋白质差异数量开始随着发育时间迅速增加，出现的动物特征蛋白质比植物特征蛋白质多得多。将蛋白质合成模式与体外翻译提取的RNA并在二维凝胶上进行电泳时获得的模式进行比较，结果表明卵母细胞和早期胚胎中沿动物 - 植物轴的蛋白质合成不对称直接反映了其mRNA沿该轴的分布。没有证据表明在卵母细胞和卵裂胚胎的动物 - 植物轴上存在局部“掩盖”的丰富信息。
