Abstract: The engineered endonuclease (EEN)-based genome editing technology is an important tool for genome function analysis and genetic improvement of biological varieties. The silkworm, Bombyx mori, is the first economic insect to be domesticated and bred by humans, and also an important model lepidopteran, which has been used for functional gene analysis in the post-genome era. In recent years, along with the rapid development of zinc finger nuclease (ZFN), transcription activator-like effector nuclease (TALEN) and CRISPR/Cas9 system-based novel genome editing technologies, the targeted genome editing technology in the silkworm also has had significant progress. In this review, the compositions and action principles of the three most commonly used EEN systems were introduced, and the establishment process of targeted genome editing technology in the silkworm and the application and research progress of this technology for point mutation of silkworm endogenous or exogenous genes, genome structure variation and integration of the exogenous genes into the silkworm genome were comprehensively and systematically summarized. This review also discussed the main problems and the corresponding strategies for the low-efficiency of the knockout of endogenous genes and integration of exogenous genes, and the off-target effects of the integration of exogenous genes in targeted genome editing techniques in the silkworm. In addition, the potential for multiplex gene editing and the development trend for the combined application and diversified development of different targeted genome editing systems of this technology in the silkworm were prospected. It is expected to provide insights and references for promoting the development of targeted genome editing technology in gene functional analysis, mutation model establishment and other research areas in insects.

Key words: Bombyx mori, genome editing, engineered endonuclease, gene manipulation, ZFN, TALEN, CRISPR/Cas9