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Title: Dual activities of an X-family DNA polymerase regulate CRISPR-induced insertional mutagenesis across species
Abstract

The canonical non-homologous end joining (c-NHEJ) repair pathway, generally viewed as stochastic, has recently been shown to produce predictable outcomes in CRISPR-Cas9 mutagenesis. This predictability, mainly in 1-bp insertions and small deletions, has led to the development of in-silico prediction programs for various animal species. However, the predictability of CRISPR-induced mutation profiles across species remained elusive. Comparing CRISPR-Cas9 repair outcomes between human and plant species reveals significant differences in 1-bp insertion profiles. The high predictability observed in human cells links to the template-dependent activity of human Polλ. Yet plant Polλ exhibits dual activities, generating 1-bp insertions through both templated and non-templated manners. Polλ knockout in plants leads to deletion-only mutations, while its overexpression enhances 1-bp insertion rates. Two conserved motifs are identified to modulate plant Polλ‘s dual activities. These findings unveil the mechanism behind species-specific CRISPR-Cas9-induced insertion profiles and offer strategies for predictable, precise genome editing through c-NHEJ.

 
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Award ID(s):
2206920
PAR ID:
10526978
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Nature Communications
Volume:
15
Issue:
1
ISSN:
2041-1723
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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