ISC, a Novel Group of Bacterial and Archaeal DNA Transposons That Encode Cas9 Homologs.

ABSTRACT:

Unlabelled

Bacterial genomes encode numerous homologs of Cas9, the effector protein of the type II CRISPR-Cas systems. The homology region includes the arginine-rich helix and the HNH nuclease domain that is inserted into the RuvC-like nuclease domain. These genes, however, are not linked to cas genes or CRISPR. Here, we show that Cas9 homologs represent a distinct group of nonautonomous transposons, which we denote ISC (insertion sequences Cas9-like). We identify many diverse families of full-length ISC transposons and demonstrate that their terminal sequences (particularly 3' termini) are similar to those of IS605 superfamily transposons that are mobilized by the Y1 tyrosine transposase encoded by the TnpA gene and often also encode the TnpB protein containing the RuvC-like endon

SUBMITTER: Kapitonov VV 

PROVIDER: S-EPMC4810608 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature