Developing mitochondrial base editors with diverse context compatibility and high fidelity via saturated spacer library.

ABSTRACT: DddA-derived cytosine base editors (DdCBEs) greatly facilitated the basic and therapeutic research of mitochondrial DNA mutation diseases. Here we devise a saturated spacer library and successfully identify seven DddA homologs by performing high-throughput sequencing based screen. DddAs of Streptomyces sp. BK438 and Lachnospiraceae bacterium sunii NSJ-8 display high deaminase activity with a strong GC context preference, and DddA of Ruminococcus sp. AF17-6 is highly compatible to AC context. We also find that different split sites result in wide divergence on off-target activity and context preference of DdCBEs derived from these DddA homologs. Additionally, we demonstrate the orthogonality between DddA and DddI_A, and successfully minimize the nuclear off-target editing by co-ex

SUBMITTER: Sun H 

PROVIDER: S-EPMC10587121 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature