An efficient and safe strategy for germ cell ‐specific automatic excision of foreign DNA in F1 hybrid transgenic silkworms

The procedure for achieving germ cell-specific automatic excision of target transgene sequences in F1 transgenic silkworms is shown in the left inset. First, the G1 transgenic activator strain silkworm is crossed with the effector strain silkworm to produce F1 double-transgenic silkworms. Then, the F1 double-transgenic silkworms are either mated with each other or backcrossed with wild-type (WT) silkworms to produce F2 target transgene-free silkworms. The right inset illustrates the specific and automatic excision ofFRT-flanked target transgenes in germ cells of F1 double-transgenic silkworms, through the use of theBombyx mori gonad-specific expression gene promoter (GSp)-drivenGAL4 gene and the Gal4-upstream activating sequence (UAS)-linkedFLP gene. AbstractThe safety of transgenic technology is a major obstacle in the popularization and use of transgenic silkworms and their products. In sericulture, only the first filial generation (F1) hybrid eggs produced by cross-breeding Japanese and Chinese original strains are usually used for the large-scale breeding of silkworms, but this may result in uncontrolled transgene dispersal during the popularization and application of the F1 hybrid transgenic eggs. To address this issue, we developed a safe and efficient strategy using the GAL4/Upstream activating sequence (UAS) system, the FLP/flippase recognition target (FRT) system, and the gonad-specific expression gene promoters (RSHP1p andNanosp) for the germ cell-specific automatic...

Source: Insect Science - June 26, 2023 Category: Biology Authors: Dingpei Long, Rongpeng Liu, Yang Huang, Anyao Fu, Yuli Zhang, Zhanzhang Hao, Qiang Li, Hanfu Xu, Zhonghuai Xiang, Aichun Zhao Tags: ORIGINAL ARTICLE Source Type: research