Engineering TadA ortholog-derived cytosine base editor without motif preference and adenosine activity limitation.

Nature communications 2024 Sep 16

filter terms:

The engineered TadA variants used in cytosine base editors (CBEs) present distinctive advantages, including a smaller size and fewer off-target effects compared to cytosine base editors that rely on natural deaminases. However, the current TadA variants demonstrate a preference for base editing in DNA with specific motif sequences and possess dual deaminase activity, acting on both cytosine and adenosine in adjacent positions, limiting their application scope. To address these issues, we employ TadA orthologs screening and multi sequence alignment (MSA)-guided protein engineering techniques to create a highly effective cytosine base editor (aTdCBE) without motif and adenosine deaminase activity limitations. Notably, the delivery of aTdCBE to a humanized mouse model of Duchenne muscular dystrophy (DMD) mice achieves robust exon 55 skipping and restoration of dystrophin expression. Our advancement in engineering TadA ortholog for cytosine editing enriches the base editing toolkits for gene-editing therapy and other potential applications. © 2024. The Author(s).

Citation

Guoling Li, Xue Dong, Jiamin Luo, Tanglong Yuan, Tong Li, Guoli Zhao, Hainan Zhang, Jingxing Zhou, Zhenhai Zeng, Shuna Cui, Haoqiang Wang, Yin Wang, Yuyang Yu, Yuan Yuan, Erwei Zuo, Chunlong Xu, Jinhai Huang, Yingsi Zhou. Engineering TadA ortholog-derived cytosine base editor without motif preference and adenosine activity limitation. Nature communications. 2024 Sep 16;15(1):8090