Adenine Base Editor C-terminal Fragment
C-terminal fragment of ABE7.10 split via Npu intein at C574. Pairs with N-terminal fragment for editor reconstitution.
Origin: SpCas9 D10A nickase (amino acids 574-1368) with Npu intein C-terminal domain
Characteristics
Contains C-terminal portion of SpCas9 D10A (residues 574-1368) including PAM recognition and DNA binding domains. Split site at C574 enables Npu intein trans-splicing with N-terminal fragment. Reference AAV construct includes U6-sgRNA expression cassette with BsmBI cloning sites for protospacer insertion and RFP dropout selection. Cbh promoter drives Cas9 fragment expression.
Applications
Dual-delivery base editing systems requiring split architecture. Includes sgRNA expression for single-vector guide RNA delivery in C-terminal construct. Validated for AAV-mediated delivery across multiple tissues. Can be adapted to other delivery platforms when combined with N-terminal fragment.
Limitations
Non-functional without N-terminal pair. Total coding sequence of reconstituted editor approaches AAV packaging limits. Requires BsmBI digestion and ligation to insert target-specific protospacer sequences in reference construct. Must be co-delivered with split-abe-nt for A-to-G editing activity.
Literature References
- Gaudelli NM, Komor AC, Rees HA, et al. (2017). Programmable base editing of A•T to G•C in genomic DNA without DNA cleavage. Nature 551:464-471 - Gaudelli 2017 Adenine Base Editor
- Levy et al. (2020). Cytosine and adenine base editing of the brain, liver, retina, heart and skeletal muscle of mice via adeno-associated viruses. Nat Biomed Eng - Levy 2020 BE3.9max