Structural highlights
Publication Abstract from PubMed
CRISPR-Cas12j is a recently identified family of miniaturized RNA-guided endonucleases from phages. These ribonucleoproteins provide a compact scaffold gathering all key activities of a genome editing tool. We provide the first structural insight into the Cas12j family by determining the cryoEM structure of Cas12j3/R-loop complex after DNA cleavage. The structure reveals the machinery for PAM recognition, hybrid assembly and DNA cleavage. The crRNA-DNA hybrid is directed to the stop domain that splits the hybrid, guiding the T-strand towards the catalytic site. The conserved RuvC insertion is anchored in the stop domain and interacts along the phosphate backbone of the crRNA in the hybrid. The assembly of a hybrid longer than 12-nt activates catalysis through key functional residues in the RuvC insertion. Our findings suggest why Cas12j unleashes unspecific ssDNA degradation after activation. A site-directed mutagenesis analysis supports the DNA cutting mechanism, providing new avenues to redesign CRISPR-Cas12j nucleases for genome editing.
Structure of the mini-RNA-guided endonuclease CRISPR-Cas12j3.,Carabias A, Fuglsang A, Temperini P, Pape T, Sofos N, Stella S, Erlendsson S, Montoya G Nat Commun. 2021 Jul 22;12(1):4476. doi: 10.1038/s41467-021-24707-3. PMID:34294706[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Carabias A, Fuglsang A, Temperini P, Pape T, Sofos N, Stella S, Erlendsson S, Montoya G. Structure of the mini-RNA-guided endonuclease CRISPR-Cas12j3. Nat Commun. 2021 Jul 22;12(1):4476. PMID:34294706 doi:10.1038/s41467-021-24707-3
