Primed adaptation tolerates extensive structural and size variations of the CRISPR RNA guide in Haloarcula hispanica.

ABSTRACT: Recent studies on CRISPR adaptation revealed that priming is a major pathway of spacer acquisition, at least for the most prevalent type I systems. Priming is guided by a CRISPR RNA which fully/partially matches the invader DNA, but the plasticity of this RNA guide has not yet been characterized. In this study, we extensively modified the two conserved handles of a priming crRNA in Haloarcula hispanica, and altered the size of its central spacer part. Interestingly, priming is insusceptible to the full deletion of 3' handle, which seriously impaired crRNA stability and interference effects. With 3' handle deletion, further truncation of 5' handle revealed that its spacer-proximal 6 nucleotides could provide the least conserved sequence required for priming. Subsequent scanning mutation fur

SUBMITTER: Gong L 

PROVIDER: S-EPMC6582329 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature