8D9I

gRAMP non-matching PFS-with Mg

Summary for 8D9I

• Entry DOI: 10.2210/pdb8d9i/pdb
• EMDB information: 27263
• Descriptor: RAMP superfamily protein, RNA (5'-R(P*UP*CP*CP*GP*GP*GP*GP*CP*AP*GP*AP*AP*AP*AP*UP*UP*GP*GP*A)-3'), RNA (35-MER), ... (4 entities in total)
• Functional Keywords: crispr, gramp, rna binding protein, rna binding protein-rna complex, rna binding protein/rna
• Biological source: Candidatus Scalindua brodae; More
• Total number of polymer chains: 3
• Total formula weight: 160622.48

Authors

Hu, C.,Nam, K.H.,Schuler, G.,Ke, A. (deposition date: 2022-06-09, release date: 2023-06-14, Last modification date: 2024-11-06)

Primary citation

Hu, C.,van Beljouw, S.P.B.,Nam, K.H.,Schuler, G.,Ding, F.,Cui, Y.,Rodriguez-Molina, A.,Haagsma, A.C.,Valk, M.,Pabst, M.,Brouns, S.J.J.,Ke, A.
Craspase is a CRISPR RNA-guided, RNA-activated protease.
Science, 377:1278-1285, 2022

PubMed Abstract: The CRISPR-Cas type III-E RNA-targeting effector complex gRAMP/Cas7-11 is associated with a caspase-like protein (TPR-CHAT/Csx29) to form Craspase (CRISPR-guided caspase). Here, we use cryo-electron microscopy snapshots of Craspase to explain its target RNA cleavage and protease activation mechanisms. Target-guide pairing extending into the 5' region of the guide RNA displaces a gating loop in gRAMP, which triggers an extensive conformational relay that allosterically aligns the protease catalytic dyad and opens an amino acid side-chain-binding pocket. We further define Csx30 as the endogenous protein substrate that is site-specifically proteolyzed by RNA-activated Craspase. This protease activity is switched off by target RNA cleavage by gRAMP and is not activated by RNA targets containing a matching protospacer flanking sequence. We thus conclude that Craspase is a target RNA-activated protease with self-regulatory capacity.

PubMed: 36007061
DOI: 10.1126/science.add5064

Experimental method

ELECTRON MICROSCOPY (3.62 Å)