RNA-binding component of the cleavage and polyadenylation factor (CPF) complex, which plays a key role in polyadenylation-dependent pre-mRNA 3'-end formation and cooperates with cleavage factors including the CFIA complex and hrp1/CFIB. Involved in poly(A) site recognition. May be involved in coupling transcription termination and mRNA 3'-end formation (By similarity). Belongs to the CFT1 family.