Cryo-EM structure of the RNA-guided ribonuclease Cas12g
Autor: | Zhuang Li, Heng Zhang, Renjian Xiao, Leifu Chang, Ruijie Han |
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Rok vydání: | 2021 |
Předmět: |
Conformational change
CRISPR-Associated Proteins Article 03 medical and health sciences Ribonucleases Bacterial Proteins CRISPR Clustered Regularly Interspaced Short Palindromic Repeats Ribonuclease Guide RNA Molecular Biology 030304 developmental biology Subgenomic mRNA Trans-activating crRNA 0303 health sciences biology Chemistry Effector Cryoelectron Microscopy 030302 biochemistry & molecular biology RNA Cell Biology Cell biology RNA Bacterial biology.protein CRISPR-Cas Systems RNA Guide Kinetoplastida |
Zdroj: | Nat Chem Biol |
ISSN: | 1552-4469 1552-4450 |
Popis: | Cas12g, the type V–G CRISPR–Cas effector, is an RNA-guided ribonuclease that targets single-stranded RNA substrate. The CRISPR–Cas12g system offers a potential platform for transcriptome engineering and diagnostic applications. We determined the structures of Cas12g–guide RNA complexes in the absence and presence of target RNA by cryo-EM to a resolution of 3.1 A and 4.8 A, respectively. Cas12g adopts a bilobed structure with miniature REC2 and Nuc domains, whereas the guide RNAs fold into a flipped ‘F’ shape, which is primarily recognized by the REC lobe. Target RNA and the CRISPR RNA (crRNA) guide form a duplex that inserts into the central cavity between the REC and NUC lobes, inducing conformational changes in both lobes to activate Cas12g. The structural insights would facilitate the development of Cas12g-based applications. The cryo-EM structures of Cas12g in complex with sgRNA in the absence and presence of target RNA reveal that the duplex formed by target RNA and crRNA binds to a central channel of Cas12g, inducing its conformational change and activation. |
Databáze: | OpenAIRE |
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