Programmable RNA targeting with the single-protein CRISPR effector Cas7-11.

  title={Programmable RNA targeting with the single-protein CRISPR effector Cas7-11.},
  author={Ahsen {\"O}zcan and Rohan N. Krajeski and Eleonora Ioannidi and Brennan Lee and Apolonia Gardner and Kira S. Makarova and Eugene V. Koonin and Omar O. Abudayyeh and Jonathan S. Gootenberg},
CRISPR-Cas interference is mediated by Cas effector nucleases that are either components of multisubunit complexes-in class 1 CRISPR-Cas systems-or domains of a single protein-in class 2 systems1-3. Here we show that the subtype III-E effector Cas7-11 is a single-protein effector in the class 1 CRISPR-Cas systems originating from the fusion of a putative Cas11 domain and multiple Cas7 subunits that are derived from subtype III-D. Cas7-11 from Desulfonema ishimotonii (DiCas7-11), when expressed… 

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