Determining the Specificity of Cascade Binding, Interference, and Primed Adaptation <i>In Vivo</i> in the <i>Escherichia coli</i> Type I-E CRISPR-Cas System.

ABSTRACT: In clustered regularly interspaced short palindromic repeat (CRISPR)-Cas (CRISPR-associated) immunity systems, short CRISPR RNAs (crRNAs) are bound by Cas proteins, and these complexes target invading nucleic acid molecules for degradation in a process known as interference. In type I CRISPR-Cas systems, the Cas protein complex that binds DNA is known as Cascade. Association of Cascade with target DNA can also lead to acquisition of new immunity elements in a process known as primed adaptation. Here, we assess the specificity determinants for Cascade-DNA interaction, interference, and primed adaptation in vivo, for the type I-E system of Escherichia coli Remarkably, as few as 5 bp of crRNA-DNA are sufficient for association of Cascade with a DNA target. Consequently, a single

SUBMITTER: Cooper LA 

PROVIDER: S-EPMC5904413 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature