4WNZ

Crystal structure of Pyrococcus furiosus Cmr4 (Cas7)

Summary for 4WNZ

• Entry DOI: 10.2210/pdb4wnz/pdb
• Descriptor: CRISPR system Cmr subunit Cmr4 (1 entity in total)
• Functional Keywords: nuclease, ramp domain, crispr-cas system, cmr cmplex, hydrolase
• Biological source: Pyrococcus furiosus DSM 3638
• Cellular location: Cytoplasm : Q8U1S9
• Total number of polymer chains: 2
• Total formula weight: 66996.87

Authors

Zhu, X.,Ye, K. (deposition date: 2014-10-15, release date: 2015-01-14, Last modification date: 2024-03-20)

Primary citation

Zhu, X.,Ye, K.
Cmr4 is the slicer in the RNA-targeting Cmr CRISPR complex
Nucleic Acids Res., 43:1257-1267, 2015

PubMed Abstract: Clustered regularly interspaced short palindromic repeat (CRISPR) loci and CRISPR-associated (Cas) proteins form an adaptive immune system that protects prokaryotes against plasmids and viruses. The Cmr complex, a type III-B effector complex, uses the CRISPR RNA (crRNA) as a guide to target RNA. Here, we show that the Cmr complex of Pyrococcus furiosus cleaves RNA at multiple sites that are 6 nt apart and are positioned relative to the 5'-end of the crRNA. We identified Cmr4 as the slicer and determined its crystal structure at 2.8 Å resolution. In the crystal, Cmr4 forms a helical filament that most likely reflects its structural organization in the Cmr complex. The putative active site is located at the inner surface of the filament where the guide and substrate RNA are thought to bind. The filament structure of Cmr4 accounts for multiple periodic cleavage sites on the substrate. Our study provides new insights into the structure and mechanism of the RNA-targeting Cmr complex.

PubMed: 25541196
DOI: 10.1093/nar/gku1355

Experimental method

X-RAY DIFFRACTION (2.8 Å)