Type-IV-A CRISPR interference

Abstract

P. oleovorans type IV-A CRISPR-Cas system targets DNA in a PAM-dependent manner and can be applied to inhibit gene expression in the absence of DNA nuclease activity. This mechanism resembles the CRISPRi method that utilizes CRISPR-Cas proteins with inactivated catalytic sites or missing nucleases to stably bind targets and block the transcription machinery. Synthetic crRNAs were used to induce CRISPR interference of the native P. oleovorans Type IV-A1 CRISPR-Cas system. Thus, these special CRISPR-Cas systems can be applied to regulate the expression of host genes and they offer possibilities to take action against pathogenic organisms.