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A panel of eGFP reporters for single base editing by APOBEC-Cas9 editosome complexes.

ABSTRACT: The prospect of introducing a single C-to-T change at a specific genomic location has become feasible with APOBEC-Cas9 editing technologies. We present a panel of eGFP reporters for quantification and optimization of single base editing by APOBEC-Cas9 editosomes. Reporter utility is demonstrated by comparing activities of seven human APOBEC3 enzymes and rat APOBEC1 (BE3). APOBEC3A and RNA binding-defective variants of APOBEC3B and APOBEC3H display the highest single base editing efficiencies. APOBEC3B catalytic domain complexes also elicit the lowest frequencies of adjacent off-target events. However, unbiased deep-sequencing of edited reporters shows that all editosomes have some degree of local off-target editing. Thus, further optimization is required to generate true single base editors and the eGFP reporters described here have the potential to facilitate this process.

SUBMITTER: Martin AS

PROVIDER: S-EPMC6345908 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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A panel of eGFP reporters for single base editing by APOBEC-Cas9 editosome complexes.

Martin A St AS Salamango D J DJ Serebrenik A A AA Shaban N M NM Brown W L WL Harris R S RS

Scientific reports 20190124 1

The prospect of introducing a single C-to-T change at a specific genomic location has become feasible with APOBEC-Cas9 editing technologies. We present a panel of eGFP reporters for quantification and optimization of single base editing by APOBEC-Cas9 editosomes. Reporter utility is demonstrated by comparing activities of seven human APOBEC3 enzymes and rat APOBEC1 (BE3). APOBEC3A and RNA binding-defective variants of APOBEC3B and APOBEC3H display the highest single base editing efficiencies. AP ...[more]

PMID: 30679582

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