image: Model for substrate-dependent HNH activation. DNA binding triggers transition from R (blue) to I (green) conformation, which serves as a conformational checkpoint between DNA binding and cleavage. In Mg2+, recognition of an on-target locks HNH in the catalytically active D conformation (red), which is destabilized after NTS release. HNH activation is prohibited when the RNA-DNA complementarity drops below a threshold (red cross). This material relates to a paper that appeared in the Aug. 4, 2017, issue of Science Advances, published by AAAS. The paper, by Y.S. Dagdas at University of California, Berkeley in Berkeley, CA, and colleagues was titled, 'A conformational checkpoint between DNA binding and cleavage by CRISPR-Cas9.' view more
Credit: [Credit: Dagdas <em>et al.</em>, Sci. Adv. 2017;3: eaao0027]