Precision genome engineering through adenine base editing in plants

The recent development of adenine base editors (ABEs) has enabled efficient and precise A-to-G base conversions in higher eukaryotic cells. Here, we show that plant-compatible ABE systems can be successfully applied to protoplasts of Arabidopsis thaliana and Brassica napus through transient transfection, and to individual plants through Agrobacterium-mediated transformation to obtain organisms with desired phenotypes. Targeted, precise A-to-G substitutions generated a single amino acid change in the FT protein or mis-splicing of the PDS3 RNA transcript, and we could thereby obtain transgenic plants with late-flowering and albino phenotypes, respectively. Our results provide ‘proof of concept’ for in planta ABE applications that can lead to induced neo-functionalization or altered mRNA splicing, opening up new avenues for plant genome engineering and biotechnology.Plant-compatible adenine base editor systems are now demonstrated to work in protoplasts and individual plants of Arabidopsis thaliana and Brassica napus, yielding plants with predicted nucleotide substitutions and stably inherited phenotypes.

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