Cleavage stimulation factor 64 kDa subunit (CstF-64) is one of the multiple factors required for polyadenylation and 3'-end cleavage of mammalian pre-mRNAs. CstF-64 is directly involved in the binding to pre-mRNAs to form cleavage bodies, which are often adjacent to Cajal and PML bodies. The CSTF complex is composed of CSTF1 (50 kDa subunit), CSTF2 (64 kDa subunit) and CSTF3 (77 kDa subunit).The synthetic peptide used to raise the antibody Cat. No. 200180 is selected from a sequence within the C-term region of human CstF-64. For blocking experiments, a 10 to 100 fold molar excess to antibody is recommended.