De Robertis E M, Mertz J E
Cell. 1977 Sep;12(1):175-82. doi: 10.1016/0092-8674(77)90195-7.
A previous report from this laboratory showed that purified DNAs are transcribed after injection into the nucleus of Xenopus laevis oocytes (Mertz and Gurdon, 1977). Here we demonstrate that at least some of the RNA synthesized is translated within these injected cells to produce the correct protein products. Injection of Simian Virus 40 DNA into oocytes induces the synthesis of at least two proteins not normally synthesized in these cells. Using two-dimensional polyacrylamide gel electrophoresis and well characterized deletion mutants of SV40 that produce proteins of smaller size, we show that these two proteins are, indeed, the virus-coded proteins VP1 and VP3. Synthesis of VP1 and VP3 is inhibited by alpha-amanitin and, therefore, presumably mediated by a type II RNA polymerase. We also present evidence indicating that a histone-like protein is induced after the injection of a cloned plasmid DNA that codes for the Drosophila melanogaster histone proteins. This in vivo coupled transcription-translation system should be useful for identifying and mapping proteins coded by cloned eucaryotic DNAs.
本实验室之前的一份报告显示，纯化的DNA在注入非洲爪蟾卵母细胞核后会被转录（默茨和格登，1977年）。在此我们证明，至少部分合成的RNA在这些注入的细胞内被翻译，以产生正确的蛋白质产物。将猴病毒40 DNA注入卵母细胞会诱导至少两种在这些细胞中通常不合成的蛋白质的合成。利用二维聚丙烯酰胺凝胶电泳以及特征明确的SV40缺失突变体（其产生较小尺寸的蛋白质），我们表明这两种蛋白质确实是病毒编码的蛋白质VP1和VP3。VP1和VP3的合成受到α-鹅膏蕈碱的抑制，因此推测是由II型RNA聚合酶介导的。我们还提供了证据表明，在注入编码黑腹果蝇组蛋白的克隆质粒DNA后会诱导一种组蛋白样蛋白质的产生。这种体内耦合转录-翻译系统应有助于鉴定和定位由克隆的真核DNA编码的蛋白质。
