Type IV-A3 CRISPR-Cas | DinG

Benz F, Camara-Wilpert S, Russel J, et al. (2024). Cell Host MicrobeCRISPRPlasmidsCCtyper

Type IV CRISPR-Cas systems are uniquely encoded on plasmids rather than bacterial chromosomes. Unlike other CRISPR systems that provide immunity against foreign genetic elements, Type IV-A3 systems mediate inter-plasmid conflicts through a distinct mechanism: they acquire spacers in trans from competing plasmids, leading to plasmid elimination during conjugation. This visualization explores the genomic neighborhoods of Type IV-A3 CRISPR-Cas loci across diverse plasmids, revealing the conserved association with the DinG helicase and the unique organization of these plasmid-encoded defense systems.