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Engineering RsDddA as mitochondrial base editor with wide target compatibility and enhanced activity.

ABSTRACT: Double-stranded DNA-specific cytidine deaminase (DddA) base editors hold great promise for applications in bio-medical research, medicine, and biotechnology. Strict sequence preference on spacing region presents a challenge for DddA editors to reach their full potential. To overcome this sequence-context constraint, we analyzed a protein dataset and identified a novel DddA_tox homolog from Ruminococcus sp. AF17-6 (RsDddA). We engineered RsDddA for mitochondrial base editing in a mammalian cell line and demonstrated RsDddA-derived cytosine base editors (RsDdCBE) offered a broadened NC sequence compatibility and exhibited robust editing efficiency. Moreover, our results suggest the average frequencies of mitochondrial genome-wide off-target editing arising from RsDdCBE are comparable to canonical DdCBE and its variants.

SUBMITTER: Cheng K

PROVIDER: S-EPMC10514076 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Engineering RsDddA as mitochondrial base editor with wide target compatibility and enhanced activity.

Cheng Kai K Li Cao C Jin Jiachuan J Qian Xuezhen X Guo Jiayin J Shen Limini L Dai YiChen Y Zhang Xue X Li Zhanwei Z Guan Yichun Y Zhou Fei F Tang Jin J Zhang Jun J Shen Bin B Lou Xin X

Molecular therapy. Nucleic acids 20230909

Double-stranded DNA-specific cytidine deaminase (DddA) base editors hold great promise for applications in bio-medical research, medicine, and biotechnology. Strict sequence preference on spacing region presents a challenge for DddA editors to reach their full potential. To overcome this sequence-context constraint, we analyzed a protein dataset and identified a novel DddAtox homolog from Ruminococcus sp. AF17-6 (RsDddA). We engineered RsDddA for mitochondrial base editi ...[more]

PMID: 37744175

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