华东师范大学李大力研究小组在研究中取得进展。他们报道了高效线粒体A-to-G碱基编辑器生成线粒体疾病模型。这一研究成果发表在2025年6月3日出版的国际学术期刊《自然—生物技术》上。

研究人员以定向进化为主题，发现TadA-8e碱基编辑器的变体，这些变体大大增加了核和线粒体腺嘌呤碱基编辑的活性，并扩大了靶向兼容性，特别是在以前不受欢迎的序列环境中。工程mtDNA编辑器（eTd-mtABEs）在人类细胞中显示出高达87%的编辑效率，大大降低了DNA和RNA的脱靶效应。与线粒体ABEs相比，将eTd-mtABE主干中的DddA替换为DNA缺口酶，链选择性A-to-G编辑平均增强了3.2倍。在大鼠细胞中，eTd-mtABEs的编辑效率比分裂的DddA转录激活因子样效应物连接脱氨酶高出145倍。该团队还通过胚胎注射植入频率高达44%的靶向突变，产生了感音神经性听力损失的大鼠。开发的eTd-mtABEs是基础研究和转化研究的高效和精确的mtDNA工程工具。

研究人员表示，现有的线粒体DNA (mtDNA) A-to-G碱基编辑器效率低。

附：英文原文

Title: Efficient mitochondrial A-to-G base editors for the generation of mitochondrial disease models

Author: Chen, Liang, Hong, Mengjia, Luan, Changming, Yuan, Meng, Wang, Yiming, Guo, Xinyuan, Fang, Yue, Huang, Hao, Dong, Xiaohua, Gao, Hongyi, Zhang, Dan, Chen, Xi, Meng, Dihao, Huang, Molin, Yi, Zongyi, Liu, Mingyao, Wei, Wensheng, Gao, Liangcai, Song, Gaojie, Zhou, Xiaoming, Li, Dali

Issue&Volume: 2025-06-03

Abstract: Existing A-to-G base editors for mitochondrial DNA (mtDNA) are limited by low efficiency. We used directed evolution to discover variants of the TadA-8e base editors that have substantially increased activity and expanded targeting compatibility for both nuclear and mitochondrial adenine base editing, especially in previously unfavored sequence contexts. The engineered mtDNA editors (eTd-mtABEs) showed up to 87% editing efficiency in human cells, with greatly reduced DNA and RNA off-target effects. Strand-selective A-to-G editing was enhanced by an average of 3.2-fold with substitution of DddA to DNA nickases in eTd-mtABE backbones compared to mitochondrial ABEs. In rat cells, editing efficiencies of eTd-mtABEs were up to 145-fold higher compared to split DddA transcription activator-like effector-linked deaminase. We also generated rats with sensorineural hearing loss by installing targeted mutations with frequencies of up to 44% through embryonic injection. The developed eTd-mtABEs are efficient and precise mtDNA-engineering tools for basic research and translational studies.

DOI: 10.1038/s41587-025-02685-x

Source: https://www.nature.com/articles/s41587-025-02685-x