8G9T
Exploiting Activation and Inactivation Mechanisms in Type I-C CRISPR-Cas3 for Genome Editing Applications
Summary for 8G9T
Entry DOI | 10.2210/pdb8g9t/pdb |
EMDB information | 29878 |
Descriptor | AcrIC9, Cas7, Cas11, ... (6 entities in total) |
Functional Keywords | crispr, type i-c, cascade, anti-crispr, hydrolase-rna complex, hydrolase/rna |
Biological source | Rhodobacter phage RcNL1 More |
Total number of polymer chains | 15 |
Total formula weight | 393286.92 |
Authors | |
Primary citation | 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 Cited by 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: 38242128DOI: 10.1016/j.molcel.2023.12.034 PDB entries with the same primary citation |
Experimental method | ELECTRON MICROSCOPY (3.6 Å) |
Structure validation
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