Efficient base editing in methylated regions with a human apobec3a-cas9 fusion
Wang X., Li J., Wang Y., Yang B., Wei J., Wu J., Wang R., Huang X., Chen J., Yang L.
Base editors (BEs) enable the generation of targeted single-nucleotide mutations, but currently used rat APOBEC1-based BEs are relatively inefficient in editing cytosines in highly methylated regions or in GpC contexts. By screening a variety of APOBEC and AID deaminases, we show that human APOBEC3A-conjugated BEs and versions we engineered to have narrower editing windows can mediate efficient C-to-T base editing in regions with high methylation levels and GpC dinucleotide content.