Priming in a permissive type I-C CRISPR-Cas system reveals distinct dynamics of spacer acquisition and loss.

ABSTRACT: CRISPR-Cas is a bacterial and archaeal adaptive immune system that uses short, invader-derived sequences termed spacers to target invasive nucleic acids. Upon recognition of previously encountered invaders, the system can stimulate secondary spacer acquisitions, a process known as primed adaptation. Previous studies of primed adaptation have been complicated by intrinsically high interference efficiency of most systems against bona fide targets. As such, most primed adaptation to date has been studied within the context of imperfect sequence complementarity between spacers and targets. Here, we take advantage of a native type I-C CRISPR-Cas system in Legionella pneumophila that displays robust primed adaptation even within the context of a perfectly matched target. Using next-genera

SUBMITTER: Rao C 

PROVIDER: S-EPMC5602111 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature