Naito M, Agata K, Otsuka K, Kino K, Ohta M, Hirose K, Perry M M, Eguchi G
National Institute of Animal Industry, Ibaraki, Japan.
Int J Dev Biol. 1991 Jun;35(2):69-75.
An experiment was carried out to investigate the expression of cloned DNA injected into the germinal disc of the chick fertilized ovum. The beta-actin-lacZ hybrid gene, MiwZ, was injected, in the closed circular form, into the cytoplasm of the germinal disc at the single-cell stage. The embryos were cultured in vitro, then in recipient eggshells up to day 4 of incubation. The survival rate of the embryos at day 4 was 42% (55/130), and the rate of embryos expressing MiwZ was 64% (35/55). Twenty-two embryos expressed the MiwZ in both embryonic and extraembryonic tissues, while the remainder expressed the MiwZ in only extraembryonic tissues. Mosaic expression was observed in most of the embryos expressing MiwZ in embryonic tissues. Expression throughout all tissues of the embryo including blood cells occurred in one case. In this case, the injected DNA was assumed to have integrated at an earlier stage. The results indicate that it is now possible to investigate the promoter activities of introduced exogenous genes as well as the effect of introduced genes on embryogenesis in early chick embryos. This technique may also facilitate the production of transgenic chicks.
进行了一项实验，以研究注射到鸡受精卵胚盘内的克隆DNA的表达情况。将β-肌动蛋白-乳糖操纵子融合基因MiwZ以闭环形式在单细胞阶段注射到胚盘的细胞质中。胚胎先在体外培养，然后在受体蛋壳中培养至孵化第4天。第4天胚胎的存活率为42%（55/130），表达MiwZ的胚胎比例为64%（35/55）。22个胚胎在胚胎组织和胚外组织中均表达MiwZ，其余的仅在胚外组织中表达MiwZ。在大多数在胚胎组织中表达MiwZ的胚胎中观察到了嵌合表达。在一个案例中，胚胎的所有组织包括血细胞中均有表达。在这种情况下，推测注射的DNA在较早阶段已经整合。结果表明，现在有可能研究导入的外源基因的启动子活性以及导入基因对早期鸡胚胚胎发生的影响。这项技术也可能有助于转基因鸡的生产。
