first type II K-homology (KH) RNA-binding domain found in archaeal cleavage and polyadenylation specificity factor (CPSF) and similar proteins
The archaeal CPSFs are predicted to be metal-dependent RNases belonging to the beta-CASP family, a subgroup of enzymes within the metallo-beta-lactamase fold. Within the CPSF family, all archaeal genomes contain one member with two N-terminal type II K-homology (KH) domains and one without. This family includes the CPSF homologs from archaea possessing N-terminal KH domains. This model corresponds to the first KH domain, which is a non-canonical type II KH domain that does not contain the signature motif GXXG (where X represents any amino acid).