Allosteric Motions of the CRISPR-Cas9 HNH Nuclease Probed by NMR and Molecular Dynamics.
East, K.W., Newton, J.C., Morzan, U.N., Narkhede, Y.B., Acharya, A., Skeens, E., Jogl, G., Batista, V.S., Palermo, G., Lisi, G.P.(2020) J Am Chem Soc 142: 1348-1358
- PubMed: 31885264 
- DOI: https://doi.org/10.1021/jacs.9b10521
- Primary Citation of Related Structures:  
6O56 - PubMed Abstract: 
CRISPR-Cas9 is a widely employed genome-editing tool with functionality reliant on the ability of the Cas9 endonuclease to introduce site-specific breaks in double-stranded DNA. In this system, an intriguing allosteric communication has been suggested to control its DNA cleavage activity through flexibility of the catalytic HNH domain. Here, solution NMR experiments and a novel Gaussian-accelerated molecular dynamics (GaMD) simulation method are used to capture the structural and dynamic determinants of allosteric signaling within the HNH domain. We reveal the existence of a millisecond time scale dynamic pathway that spans HNH from the region interfacing the adjacent RuvC nuclease and propagates up to the DNA recognition lobe in full-length CRISPR-Cas9. These findings reveal a potential route of signal transduction within the CRISPR-Cas9 HNH nuclease, advancing our understanding of the allosteric pathway of activation. Further, considering the role of allosteric signaling in the specificity of CRISPR-Cas9, this work poses the mechanistic basis for novel engineering efforts aimed at improving its genome-editing capability.
Organizational Affiliation: 
Department of Molecular Biology, Cell Biology & Biochemistry , Brown University , Providence , Rhode Island 02903 , United States.