CRISPR

CRISPR is an RNA-based immune system utilized by bacteria and archaea to target foreign genetic elements like viral DNA, transposons, and plasmids. An RNA-Protein surveillance complex called Cascade is used to find foreign DNA based on a sense antisense mechanism (between RNA in Cascade and viral DNA). Cascade binding melts viral DNA and recruits a nuclease-helicase called Cas3 that degrades DNA and hence stop viral propagation.