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

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.

SUBMITTER: Koblan LW

PROVIDER: S-EPMC6126947 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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

Koblan Luke W LW Doman Jordan L JL Wilson Christopher C Levy Jonathan M JM Tay Tristan T Newby Gregory A GA Maianti Juan Pablo JP Raguram Aditya A Liu David R DR

Nature biotechnology 20180529 9

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. ...[more]

PMID: 29813047

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