Mitochondrial DNA editing in mice with DddA-TALE fusion deaminases

DddA-derived cytosine base editors (DdCBEs), composed of the split interbacterial toxin DddA(tox), transcription activator-like effector (TALE), and uracil glycosylase inhibitor (UGI), enable targeted C-to-T base conversions in mitochondrial DNA (mtDNA). Here, we demonstrate highly efficient mtDNA editing in mouse embryos using custom-designed DdCBEs. We target the mitochondrial gene, MT-ND5 (ND5), which encodes a subunit of NADH dehydrogenase that catalyzes NADH dehydration and electron transfer to ubiquinone, to obtain several mtDNA mutations, including m.G12918A associated with human mitochondrial diseases and m.C12336T that incorporates a premature stop codon, creating mitochondrial disease models in mice and demonstrating a potential for the treatment of mitochondrial disorders. Split DddA-derived base editors fused to TALEs enable mitochondrial DNA editing. Here the authors demonstrate their use in mouse embryos with germline transmission.

Automated summary

This study demonstrates highly efficient mitochondrial DNA editing using DdCBEs in mouse embryos, creating mitochondrial disease models and showing the potential for treating mitochondrial disorders. The authors show the use of split DddA-derived base editors fused to TALEs in mouse embryos with germline transmission.