Cho, Sung-Ik Lim, Kayeong Hong, Seongho Lee, Jaesuk Kim, Annie Lim, Chae Jin Ryou, Seungmin Lee, Ji Min Mok, Young Geun Chung, Eugene Kim, Sanghun Han, Seunghun Cho, Sang-Mi Kim, Jieun Kim, Eun-Kyoung Nam, Ki-Hoan Oh, Yeji Choi, Minkyung An, Tae Hyeon Oh, Kyoung-Ji Lee, Seonghyun Lee, Hyunji Kim, Jin-Soo 2024-02-13T05:30:14Z 2024-02-13T05:30:14Z 2024-02-13 2024-01 0092-8674 https://pubs.kist.re.kr/handle/201004/148612 DddA-derived cytosine base editors (DdCBEs) and transcription activator -like effector (TALE) -linked deaminases (TALEDs) catalyze targeted base editing of mitochondrial DNA (mtDNA) in eukaryotic cells, a method useful for modeling of mitochondrial genetic disorders and developing novel therapeutic modalities. Here, we report that A -to -G -editing TALEDs but not C -to -T -editing DdCBEs induce tens of thousands of transcriptome-wide off -target edits in human cells. To avoid these unwanted RNA edits, we engineered the substrate -binding site in TadA8e, the deoxy-adenine deaminase in TALEDs, and created TALED variants with fine-tuned deaminase activity. Our engineered TALED variants not only reduced RNA off -target edits by >99% but also minimized off -target mtDNA mutations and bystander edits at a target site. Unlike wildtype versions, our TALED variants were not cytotoxic and did not cause developmental arrest of mouse embryos. As a result, we obtained mice with pathogenic mtDNA mutations, associated with Leigh syndrome, which showed reduced heart rates. English Cell Press Engineering TALE-linked deaminases to facilitate precision adenine base editing in mitochondrial DNA Article 10.1016/j.cell.2023.11.035 1 Cell, v.187, no.1, pp.95 - 109.e26 Cell 187 1 95 109.e26 Y scie scopus 001155339400001 2-s2.0-85181051805 Biochemistry & Molecular Biology Cell Biology Biochemistry & Molecular Biology Cell Biology Article RNA OFF-TARGET STEM-CELLS MUTATIONS EDITORS NUCLEAR