Structure of the Saccharolobus solfataricus type III-D CRISPR effector

DOI: 10.1016/j.crstbi.2023.100098

Authors: Giuseppe Cannone (MRC Laboratory of Molecular Biology) , Dmytro Kompaniiets (University of Glasgow) , Shirley Graham (University of St Andrews) , Malcolm F. White (University of St Andrews) , Laura Spagnolo (University of Glasgow)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Current Research In Structural Biology , VOL 9

State: Published (Approved)
Published: February 2023
Diamond Proposal Number(s): 16637

Abstract: CRISPR-Cas is a prokaryotic adaptive immune system, classified into six different types, each characterised by a signature protein. Type III systems, classified based on the presence of a Cas10 subunit, are rather diverse multi-subunit assemblies with a range of enzymatic activities and downstream ancillary effectors. The broad array of current biotechnological CRISPR applications is mainly based on proteins classified as Type II, however recent developments established the feasibility and efficacy of multi-protein Type III CRISPR-Cas effector complexes as RNA-targeting tools in eukaryotes. The crenarchaeon Saccharolobus solfataricus has two type III system subtypes (III–B and III-D). Here, we report the cryo-EM structure of the Csm Type III-D complex from S. solfataricus (SsoCsm), which uses CRISPR RNA to bind target RNA molecules, activating the Cas10 subunit for antiviral defence. The structure reveals the complex organisation, subunit/subunit connectivity and protein/guide RNA interactions of the SsoCsm complex, one of the largest CRISPR effectors known.

Diamond Keywords: Archaea

Subject Areas: Biology and Bio-materials

Diamond Offline Facilities: Electron Bio-Imaging Centre (eBIC)
Instruments: Krios I-Titan Krios I at Diamond

Added On: 15/02/2023 08:29

Discipline Tags:

Genetics Structural biology Life Sciences & Biotech

Technical Tags:

Microscopy Electron Microscopy (EM) Cryo Electron Microscopy (Cryo EM)