University of Massachusetts

University of Toronto

Wisconsin Alumni Research Foundation

Northwestern University

Yan Zhang

Erik J Sontheimer

Karen Maxwell

Rakhi Rajan

Nadia Amrani

Alan Davidson

April Pawluk

Jooyoung Lee

Alfonso Mondragon

Many strains of the human pathogencarry a compact Cas9 (NmeCas9) that can serve to limit genetic exchange via natural transformation. Cas9 orthologues (including NmeCas9) have recently been adopted for RNA-guided genome engineering and DNA binding, adding to the need to define better their activities and properties. The present invention examines DNA cleavage activities and substrate requirements of NmeCas9, including a set of unusually complex PAM recognition patterns. Unexpectedly, NmeCas9 is found able to cleave single-stranded DNA (ssDNA) targets in a manner that is RNA-guided but both PAM- and tracrRNA-independent. Beyond the requirement for guide-target pairing, this activity has no apparent sequence requirements, and the cleavage sites are measured from the 5' end of the DNA substrate's RNA-paired region. These results indicate that tracrRNA domains are not strictly required for enzymatic activation of NmeCas9, and expand the list of targeting activities exhibited by these revolutionary RNA-guided nucleases.

DNase H activity of Neisseria meningitidis Cas9

The present invention is related to the field of CRISPR-Cas9 gene editing platforms. In particular, the present invention has identified Type II-C Cas9 anti-CRISPR (Acr) inhibitors that control Cas9 gene editing activity. Co-administration of such Acr inhibitors may provide an advantageous adjunct in permitting safe and practical biological therapeutics through spatial or temporal control of Cas9 activity; controlling Cas9-based gene drives in wild populations to reduce the ecological consequences of such forced inheritance schemes; and contributing to general research into various biotechnological, agricultural, and medical applications of gene editing technologies.

Anti-CRISPR compounds and methods of use

Growing community of inventors

Shrewsbury, MA, United States of America

Yan Zhang