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BE-PLUS: a new base editing tool with broadened editing window and enhanced fidelity

Cell Researchvolume 28pages855861 (2018) | Download Citation

Abstract

Base editor (BE), containing a cytidine deaminase and catalytically defective Cas9, has been widely used to perform base editing. However, the narrow editing window of BE limits its utility. Here, we developed a new editing technology named as base editor for programming larger C to U (T) scope (BE-PLUS) by fusing 10 copies of GCN4 peptide to nCas9(D10A) for recruiting scFv-APOBEC-UGI-GB1 to the target sites. The new system achieves base editing with a broadened window, resulting in an increased genome-targeting scope. Interestingly, the new system yielded much fewer unwanted indels and non-C-to-T conversions. We also demonstrated its potential use in gene disruption across the whole genome through induction of stop codons (iSTOP). Taken together, the BE-PLUS system offers a new editing tool with increased editing window and enhanced fidelity.

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Acknowledgements

We thank members of Huang and Chen laboratories for helpful discussions. We are grateful to Dr. Tian Chi from ShanghaiTech University for excellent language editing. This work was supported by the National Key R&D Program (2017YFC1001903, 2016YFC0905901), the National Science Foundation of China (31471400, 39870046, 81270605, 30971066, 81470324) and Major technological innovation plan of hospital (SWH2016ZDCX1003, SWH2016ZDCX1010).

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Author notes

  1. These authors contributed equally: Wen Jiang, Songjie Feng

Affiliations

  1. Department of Hematology, Southwest Hospital, Third Military Medical University (Army Medical University), 400038, Chongqing, China

    • Wen Jiang
    • , Yu Hou
    •  & Jieping Chen
  2. School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China

    • Songjie Feng
    • , Shisheng Huang
    • , Wenxia Yu
    • , Guanglei Li
    • , Guang Yang
    • , Yajing Liu
    • , Yu Zhang
    • , Jia Chen
    •  & Xingxu Huang
  3. University of Chinese Academy of Sciences, 100049, Beijing, China

    • Songjie Feng
    • , Yajing Liu
    •  & Lei Zhang
  4. Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 201210, Shanghai, China

    • Songjie Feng
    • , Yajing Liu
    •  & Lei Zhang

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Contributions

X.H., J.C., S.F., and W.J. designed the study. W.J., S.F., W.Y., G.L., G.Y., Y.L., Y.Z., L.Z., and Y.H. performed the experiments. W.J., S.F., and S.H. analysed the data. W.J. and S.F. wrote the paper.

Competing interests

The authors declare no competing interests.

Corresponding authors

Correspondence to Jieping Chen or Xingxu Huang.

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DOI

https://doi.org/10.1038/s41422-018-0052-4