Here we developed an adenine transversion base editor, AYBE, for A-to-C and A-to-T transversion editing in mammalian cells by fusing an adenine base editor (ABE) with hypoxanthine excision protein N-methylpurine DNA glycosylase (MPG). We also engineered AYBE variants enabling targeted editing at genomic loci with higher transversion editing activity (up to 72% for A-to-C or A-to-T editing).
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Expression plasmids used in this study have been deposited at Addgene and will be available at https://www.addgene.org/Huawei_Tong/ (Addgene plasmid nos. 193966–193968). All data supporting the findings of this study are available in the paper (and in its Supplementary Information files). Targeted amplicon sequencing data have been deposited at the Sequence Read Archive and can be accessed at https://www.ncbi.nlm.nih.gov/bioproject/PRJNA874457 (ref. 21). All relevant original data are available from the corresponding authors upon reasonable request.
Custom scripts for CRISPResso analyses supporting the findings of this study are available from the corresponding author upon reasonable request.
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We acknowledge technical support from the FACS facility of HuiGene Therapeutics Co., Ltd. This work was supported by HuiGene Therapeutics Co., Ltd. (H.T.).
H.T. discloses a patent application related to the proteins described in this manuscript. H.T., N.L., Y.L., J.L, Q.M., D.W. and J.L. are employees of HuiGene Therapeutics Co., Ltd. H.Y. is a founder of HuiGene Therapeutics Co., Ltd. and HuiEdit Therapeutics Co., Ltd. The remaining authors declare no competing interests.
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Supplementary Figs. 1–16 and Supplementary Tables 1–4
Supplementary Table 5
gRNA spacers, barcoded primers and target sequences used in this study
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Tong, H., Wang, X., Liu, Y. et al. Programmable A-to-Y base editing by fusing an adenine base editor with an N-methylpurine DNA glycosylase. Nat Biotechnol (2023). https://doi.org/10.1038/s41587-022-01595-6