CPSF plays a key role in pre-mRNA 3'-end formation, recognizing the AAUAAA signal sequence and interacting with poly(A)polymerase and other factors to bring about cleavage and poly(A) addition (By similarity). Required for antisense-RNA-mediated gene silencing (PubMed:17008405). Component of the CPSF complex, at least composed of CPSF160, CPSF100, CPSF73-I, CPSF73-II, CPSF30, FY and FIPS5. Forms a complex with cleavage and polyadenylation specificity factor (CPSF) subunits FY, PAPS2, CSTF50, CPSF30, CPSF73-I, CPSF73-II and CPSF160. Localized in the cytoplasm when associated with CPSF30. Impaired antisense-RNA-mediated gene silencing. Early flowering. Belongs to the metallo-beta-lactamase superfamily. RNA-metabolizing metallo-beta-lactamase-like family. CPSF2/YSH1 subfamily.