8GAM

Exploiting Activation and Inactivation Mechanisms in Type I-C CRISPR-Cas3 for Genome Editing Applications

8GAM の概要

• エントリーDOI: 10.2210/pdb8gam/pdb
• EMDBエントリー: 29900
• 分子名称: Cas7, Phage associated protein, Cas11, ... (7 entities in total)
• 機能のキーワード: crispr, type i-c, cascade, anti-crispr, hydrolase-rna-dna complex, hydrolase/rna/dna
• 由来する生物種: Neisseria lactamica; 詳細
• タンパク質・核酸の鎖数: 15
• 化学式量合計: 432691.69

構造登録者

Hu, C.,Nam, K.H.,Ke, A. (登録日: 2023-02-23, 公開日: 2024-03-06)

主引用文献

Hu, C.,Myers, M.T.,Zhou, X.,Hou, Z.,Lozen, M.L.,Nam, K.H.,Zhang, Y.,Ke, A.
Exploiting activation and inactivation mechanisms in type I-C CRISPR-Cas3 for genome-editing applications.
Mol.Cell, 84:463-475.e5, 2024

PubMed Abstract: Type I CRISPR-Cas systems utilize the RNA-guided Cascade complex to identify matching DNA targets and the nuclease-helicase Cas3 to degrade them. Among the seven subtypes, type I-C is compact in size and highly active in creating large-sized genome deletions in human cells. Here, we use four cryoelectron microscopy snapshots to define its RNA-guided DNA binding and cleavage mechanisms in high resolution. The non-target DNA strand (NTS) is accommodated by I-C Cascade in a continuous binding groove along the juxtaposed Cas11 subunits. Binding of Cas3 further traps a flexible bulge in NTS, enabling NTS nicking. We identified two anti-CRISPR proteins AcrIC8 and AcrIC9 that strongly inhibit Neisseria lactamica I-C function. Structural analysis showed that AcrIC8 inhibits PAM recognition through allosteric inhibition, whereas AcrIC9 achieves so through direct competition. Both Acrs potently inhibit I-C-mediated genome editing and transcriptional modulation in human cells, providing the first off-switches for type I CRISPR eukaryotic genome engineering.

PubMed: 38242128
DOI: 10.1016/j.molcel.2023.12.034

実験手法

ELECTRON MICROSCOPY (3.46 Å)