Work

Anti-CRISPR protein AcrIIA5 can enhance the activity and security of prime editing

Year: 2025
Type: article
Abstract: Prime editing (PE) enables the precise installation of intended base substitutions, small deletions or small insertions into the genome of living cells. While the use of Cas9 nickase can avoid DNA double-strand breaks (DSB), undesired insertions and deletions (indels) often accompany the correct edits, particularly when PE activity increased. Here we show that the anti-CRISPR (Acr) protein AcrIIA5 can significantly enhance PE activity by up to 8.2-fold while markedly reducing byproduct indels. Further investigation reveals that AcrIIA5 can promote PE across various approaches (PE2, PE3, PE4, PE5, and PE6), edit types (substitutions, insertions and deletions), and endogenous loci. Mechanistically, AcrIIA5 appears to inhibit the re-nicking activity of PE complex rather than enhancing the core editing machinery itself, suggesting a distinct mode of interaction with Cas9. Overall, we demonstrate that a known “inhibitor” Acr protein can unexpectedly acting as an “enhancer” of CRISPR/Cas-based genome editing, providing an effective strategy to optimize PE specificity and activity. Prime editing enables precise genetic modification but often suffers from unwanted byproducts. Here, authors show that the anti-CRISPR protein AcrIIA5 unexpectedly enhances prime editing efficiency while reducing unintended indels, offering an effective strategy to improve activity and specificity.
Language: English
Open Access status: gold
Estimated APC paid: $6,990
OpenAlex ID: W4417478495
FWCI: 0.783
Cites: 47
Cited by: 3
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