The Revolution Continues: Newly Discovered Systems Expand the CRISPR-Cas Toolkit

Karthik Murugan; Kesavan Babu; Ramya Sundaresan; Rakhi Rajan; Dipali G Sashital

doi:10.1016/j.molcel.2017.09.007

The Revolution Continues: Newly Discovered Systems Expand the CRISPR-Cas Toolkit

Mol Cell. 2017 Oct 5;68(1):15-25. doi: 10.1016/j.molcel.2017.09.007.

Authors

Karthik Murugan¹, Kesavan Babu², Ramya Sundaresan², Rakhi Rajan², Dipali G Sashital³

Affiliations

¹ Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 2437 Pammel Drive, Ames, IA 50011, USA.
² Department of Chemistry and Biochemistry, Stephenson Life Sciences Research Center, University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019, USA.
³ Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 2437 Pammel Drive, Ames, IA 50011, USA. Electronic address: sashital@iastate.edu.

Abstract

CRISPR-Cas systems defend prokaryotes against bacteriophages and mobile genetic elements and serve as the basis for revolutionary tools for genetic engineering. Class 2 CRISPR-Cas systems use single Cas endonucleases paired with guide RNAs to cleave complementary nucleic acid targets, enabling programmable sequence-specific targeting with minimal machinery. Recent discoveries of previously unidentified CRISPR-Cas systems have uncovered a deep reservoir of potential biotechnological tools beyond the well-characterized Type II Cas9 systems. Here we review the current mechanistic understanding of newly discovered single-protein Cas endonucleases. Comparison of these Cas effectors reveals substantial mechanistic diversity, underscoring the phylogenetic divergence of related CRISPR-Cas systems. This diversity has enabled further expansion of CRISPR-Cas biotechnological toolkits, with wide-ranging applications from genome editing to diagnostic tools based on various Cas endonuclease activities. These advances highlight the exciting prospects for future tools based on the continually expanding set of CRISPR-Cas systems.

Keywords: C2c1; C2c2; CRISPR-Cas; Cas12; Cas13; Cas9; Cpf1; RNA-guided DNA cleavage; RNA-guided RNA cleavage; genome editing.

Publication types

Review

MeSH terms

Bacteria / genetics
Bacteria / immunology
Bacteria / virology
Bacterial Proteins / chemistry
Bacterial Proteins / classification
Bacterial Proteins / genetics*
Bacterial Proteins / metabolism
Bacteriophages / growth & development
CRISPR-Cas Systems*
Clustered Regularly Interspaced Short Palindromic Repeats*
Endonucleases / chemistry
Endonucleases / classification
Endonucleases / genetics*
Endonucleases / metabolism
Gene Editing / methods*
Genetic Engineering
Genome*
Humans
Models, Molecular
Protein Conformation
Protein Domains
RNA, Guide, CRISPR-Cas Systems / genetics
RNA, Guide, CRISPR-Cas Systems / metabolism
Transcription, Genetic

Substances

Bacterial Proteins
RNA, Guide, CRISPR-Cas Systems
Endonucleases

Abstract

Publication types

MeSH terms

Substances

Grants and funding