TY - JOUR
AU - Koonin, Eugene V.
AB - 


CRISPR–Cas systems form two major classes that differ in the organization of their effector modules. The effector modules of class 2 systems consist of a single large protein, which makes them the best candidates for genome-editing tools.


Computational methods of microbial genome screening were developed for the comprehensive identification of class 2 CRISPR–cas loci. Using these approaches, six new subtypes of the class 2 system were discovered, which brings the total for this class to three types and 10 subtypes.


Type II and type V CRISPR–Cas effectors are homologues of TnpB proteins, which are a poorly characterized family of nucleases that are encoded by bacterial and archaeal transposons. The different subtypes of these two types seem to have evolved independently, through the integration of TnpB-encoding transposons near CRISPR arrays.


Type VI effectors are large proteins that contain two RNase domains of the higher eukaryotes and prokaryotes nucleotide-binding domain (HEPN) superfamily and that have been shown to, or are predicted to, specifically target RNA.


The diverse class 2 CRISPR–Cas systems that have been discovered provide opportunities for the construction of versatile genome-editing tools.



TI - Diversity and evolution of class 2 CRISPR–Cas systems
JF - Nature Reviews Microbiology
DO - 10.1038/nrmicro.2016.184
DA - 2017-01-23
UR - https://www.deepdyve.com/lp/springer-journals/diversity-and-evolution-of-class-2-crispr-cas-systems-T5YXJtqtE6
SP - 169
EP - 182
VL - 15
IS - 3
DP - DeepDyve
ER -