家蚕卵显微注射操作对蚕卵孵化及畸形蚕发生的影响

Effect of different microinjection operation of eggs on egg hatchability and the occurrence of malformation in the silkworm, Bombyx mori

早期胚胎显微注射是目前获得转基因家蚕Bombyx mori的主要途径。显微注射操作对蚕卵的损伤导致注射后的蚕卵孵化率降低,是家蚕转基因工作的主要障碍之一。本研究对不同卵龄的蚕卵进行了开孔或注射实验,并对产后5h的蚕卵上背侧、腹侧、前极、后极和中央等5个不同的位置进行了开孔实验,调查了卵孵化率和体形异常蚕的产生情况。结果表明:较早卵龄期的注射或从蚕卵背侧的注射可以获得高的孵化率。腹侧注射产生大量的体形异常蚕而背侧注射的蚕完全正常。通过调整注射时期和注射位置避开上述影响可以减少死卵和畸形蚕,提高孵化率。本研究为改进家蚕转基因操作技术提供了有效的参考。

The technology of microinjecting preblastodermic eggs is currently the main operation to obtain the transgenic silkworm （Bombyx mori）. Microinjection will cause damage to silkworm eggs, and lead to the decrease in the hatchability of the injected eggs, which is one of the major problems of the transgenic technology of the silkworm. In this study, the eggs were microinjected at different embryonic age and on different positions of egg including dorsal side, ventral side, anterior pole, posterior pole and the center at 5 h after egg laying, to investigate the effect of these factors on egg hatchability and the occurrence of larval malformation in the silkworm. The results showed that microinjection operated at the earlier embryonic age or from the dorsal side increased the hatchability of those injected eggs. Microinjeetion from the dorsal side brought out normal larvae, while mieroinjection from the ventral side led to a lot of malformed larvae. It is so inferred that choosing the suitable injection time and correct position will eliminate the occurrence of malformation and increase egg hatchability to some extent. This study provides a useful reference for improving the transgenic operation of the silkworm.