CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) and associated Cas proteins comprise a system for heritable host defense by prokaryotic cells against phage and other foreign DNA; Cas2 is present in majority of CRISPR/Cas systems along with Cas1; RNAse specific to U-rich regions; Possesses an RRM/ferredoxin fold
Jiyao W et al.(2023). "The conserved domain database in 2023.",