Increasing the Efficiency and Targeting Range of Cytidine Base Editors Through Fusion of a Single-stranded DNA-binding Protein Domain

Overview

Journal Nat Cell Biol

Specialty Cell Biology

Date 2020 May 13

PMID 32393889

Citations 55

Authors

Xiaohui Zhang

Liang Chen

Biyun Zhu

Liren Wang

Caiyu Chen

Mengjia Hong

Yifan Huang

Huiying Li

Honghui Han

Bailian Cai

Weishi Yu

Shuming Yin

Lei Yang

Zuozhen Yang

Meizhen Liu

Ying Zhang

Zhiyong Mao

Yuxuan Wu

Mingyao Liu

Dali Li

Affiliations

Soon will be listed here.

Abstract

Cytidine base editors are powerful genetic tools that catalyse cytidine to thymidine conversion at specific genomic loci, and further improvement of the editing range and efficiency is critical for their broader applications. Through insertion of a non-sequence-specific single-stranded DNA-binding domain from Rad51 protein between Cas9 nickase and the deaminases, serial hyper cytidine base editors were generated with substantially increased activity and an expanded editing window towards the protospacer adjacent motif in both cell lines and mouse embryos. Additionally, hyeA3A-BE4max selectively catalysed cytidine conversion in TC motifs with a broader editing range and much higher activity (up to 257-fold) compared with eA3A-BE4max. Moreover, hyeA3A-BE4max specifically generated a C-to-T conversion without inducing bystander mutations in the haemoglobin gamma gene promoter to mimic a naturally occurring genetic variant for amelioration of β-haemoglobinopathy, suggesting the therapeutic potential of the improved base editors.

Citing Articles

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