K. Chae, C. Dawson, C. Valentin, B. Contreras, J. Zapletal, K. M. Myles and Z. N. Adelman,
PNAS Nexus,
2022.
Promising genetics-based approaches are being developed to reduce or prevent the transmission of mosquito-vectored diseases. Less clear is how such transgenes can be removed from the environment, a concern that is particularly relevant for highly invasive gene drive transgenes. Here, we lay the groundwork for a transgene removal system based on single-strand annealing (SSA), a eukaryotic DNA repair mechanism. An SSA-based rescuer strain (kmoRG) was engineered to have direct repeat sequences (DRs) in the Ae. aegypti kynurenine 3-monooxygenase (kmo) gene flanking the intervening transgenic cargo genes, DsRED and EGFP. Targeted induction of DNA double-strand breaks (DSBs) in the DsRED transgene successfully triggered complete elimination of the entire cargo from the kmoRG strain, restoring the wild-type kmo gene and thereby normal eye pigmentation. Our work establishes the framework for strategies to remove transgene sequences during the evaluation and testing of modified strains for genetics-based mosquito control.
Image from K. Chae, C. Dawson, C. Valentin, B. Contreras, J. Zapletal, K. M. Myles and Z. N. Adelman(2022) doi: 10.1093/pnasnexus/pgac037
https://www.geneconvenevi.org/wp-content/uploads/2022/04/PNAS-Nexus-2.png300300David Obrochta/wp-content/uploads/2019/10/GC-color-logo-for-header-3277-x-827-1030x260.pngDavid Obrochta2022-04-28 08:54:372022-04-28 09:28:48Engineering a self-eliminating transgene in the yellow fever mosquito, Aedes aegypti