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; Large proteins, some contain Zn-finger domain. Fused to N-terminal HD domain; signature gene for I-D subtype; also known as Csc3 family
Jiyao W et al.(2023). "The conserved domain database in 2023.",