EFFICIENT TRANSGENE-FREE GENOME EDITING IN PLANTS IN THE T0 GENERATION BASED ON A CO-EDITING STRATEGY

Fecha de publicación: 16/01/2025
Fuente: WIPO "tomato"
Transgene-free genome editing of plants in T0 generation is highly desirable but challenging, especially in perennials and vegetatively propagated plants. Here is provided a co-editing strategy for generating transgene-free, gene-edited plants via Agrobacterium-mediated transient expression of cytosine base editor (CBE)/gRNA-Cas 12a/crRNA-GFP in plants. Specifically, CBE/gRNA was used to base edit the AES gene to confer resistance to herbicide chlorsulfuron as a selection marker, which has no negative effects on plant phenotypes; Casl2a/crRNA was used for editing genes(s) of interest; GFP was used for selecting transgene-free transformants. Using this approach, transgene- free genome-edited plants were efficiently generated for various genes (either individual or multiplex) in tomato, tobacco, potato, and citrus in the T0 generation. The biallelic/homozygous transgene-free mutation rates for target genes among herbicide-resistant transformants ranged from 8% to 50%. Whole genome sequencing further confirmed transgene-free and absence of off- target mutations in the edited plants. The co-editing strategy is efficient for generating transgene- free, genome-edited plants in the T0 generation, thus being a potent tool for plant genetic improvement.