title: C2c2 is a single-component programmable RNA-guided RNA-targeting CRISPR effector.
abstract: The clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated genes (Cas) adaptive immune system defends microbes against foreign genetic elements via DNA or RNA-DNA interference. We characterize the class 2 type VI CRISPR-Cas effector C2c2 and demonstrate its RNA-guided ribonuclease function. C2c2 from the bacterium Leptotrichia shahii provides interference against RNA phage. In vitro biochemical analysis shows that C2c2 is guided by a single CRISPR RNA and can be programmed to cleave single-stranded RNA targets carrying complementary protospacers. In bacteria, C2c2 can be programmed to knock down specific mRNAs. Cleavage is mediated by catalytic residues in the two conserved Higher Eukaryotes and Prokaryotes Nucleotide-binding (HEPN) domains, mutations of which generate catalytically inactive RNA-binding proteins. These results broaden our understanding of CRISPR-Cas systems and suggest that C2c2 can be used to develop new RNA-targeting tools.
authors.affiliation: Department of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. McGovern Institute for Brain Research at MIT, Cambridge, MA 02139, USA. Departments of Brain and Cognitive Science and Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Omar O
authors.initials: OO
authors.lastname: Abudayyeh
authors.affiliation: Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. McGovern Institute for Brain Research at MIT, Cambridge, MA 02139, USA. Departments of Brain and Cognitive Science and Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Gootenberg
authors.affiliation: Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. McGovern Institute for Brain Research at MIT, Cambridge, MA 02139, USA. Departments of Brain and Cognitive Science and Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Silvana
authors.initials: S
authors.lastname: Konermann
authors.affiliation: Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. McGovern Institute for Brain Research at MIT, Cambridge, MA 02139, USA. Departments of Brain and Cognitive Science and Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Julia
authors.initials: J
authors.lastname: Joung
authors.affiliation: Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. McGovern Institute for Brain Research at MIT, Cambridge, MA 02139, USA. Departments of Brain and Cognitive Science and Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Ian M
authors.initials: IM
authors.lastname: Slaymaker
authors.affiliation: Department of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. McGovern Institute for Brain Research at MIT, Cambridge, MA 02139, USA. Departments of Brain and Cognitive Science and Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: David B T
authors.initials: DB
authors.lastname: Cox
authors.affiliation: Skolkovo Institute of Science and Technology, Skolkovo, 143025, Russia. National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
authors.forename: Sergey
authors.initials: S
authors.lastname: Shmakov
authors.affiliation: National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
authors.forename: Kira S
authors.initials: KS
authors.lastname: Makarova
authors.affiliation: Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Semenova
authors.affiliation: Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.
authors.forename: Leonid
authors.initials: L
authors.lastname: Minakhin
authors.affiliation: Skolkovo Institute of Science and Technology, Skolkovo, 143025, Russia. Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA. Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, 123182, Russia.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Severinov
authors.affiliation: Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Aviv
authors.initials: A
authors.lastname: Regev
authors.affiliation: Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA. Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Eric S
authors.initials: ES
authors.lastname: Lander
authors.affiliation: National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA. zhang@broadinstitute.org koonin@ncbi.nlm.nih.gov.
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Koonin
authors.affiliation: Department of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. McGovern Institute for Brain Research at MIT, Cambridge, MA 02139, USA. Departments of Brain and Cognitive Science and Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. zhang@broadinstitute.org koonin@ncbi.nlm.nih.gov.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhang
mesh_terms: D056704:Adaptive Immunity / Q000235:genetics*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D064113:CRISPR-Cas Systems; D064112:Clustered Regularly Interspaced Short Palindromic Repeats; D004722:Endoribonucleases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000276:immunology / Q000821:virology; D055785:Gene Knockdown Techniques; D056426:Genetic Loci; D045183:Leptotrichia / Q000201:enzymology* / Q000235:genetics / Q000276:immunology; D017909:Levivirus / Q000276:immunology; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D059367:RNA Cleavage; D000094704:RNA, Guide, CRISPR-Cas Systems / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D000094704:RNA, Guide, CRISPR-Cas Systems; D004722:Endoribonucleases