Improving cytidine and adenine base editors by expression optimization and ancestral reconstruction

  • Nat Biotechnol. 2018 Oct;36(9):843-846. doi: 10.1038/nbt.4172.
Luke W Koblan  1  2  3 ,  Jordan L Doman  1  2  3 ,  Christopher Wilson  1  2  3 ,  Jonathan M Levy  1  2  3 ,  Tristan Tay  1  2  3 ,  Gregory A Newby  1  2  3 ,  Juan Pablo Maianti  1  2  3 ,  Aditya Raguram  1  2  3 ,  David R Liu  1  2  3
Affiliations
  • 1. Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA.
  • 2. Howard Hughes Medical Institute, Harvard University, Cambridge, Massachusetts, USA.
  • 3. Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, USA.
PMID: 29813047 DOI: 10.1038/nbt.4172
Abstract

Base editors enable targeted single-nucleotide conversions in genomic DNA. Here we show that expression levels are a bottleneck in base-editing efficiency. We optimize cytidine (BE4) and adenine (ABE7.10) base editors by modification of nuclear localization signals (NLS) and codon usage, and ancestral reconstruction of the deaminase component. The resulting BE4max, AncBE4max, and ABEmax editors correct pathogenic SNPs with substantially increased efficiency in a variety of mammalian cell types.