PRMT5 interacts with the RD2 and ZNF domains of BCL6 via its N terminus. (A) Schematic of plasmids encoding either the V5-tagged full-length BCL6 or domains of BCL6 used in panel B. (B) Co-IP experiments of PRMT5 with V5-tagged full-length or BTB/POZ, RD2 and ZNF domains of BCL6. (C) GST pull-down assay of recombinant GST-PRMT5 with BCL6 RD2-V5/His proteins. (D) V5 pull-down assay of recombinant GST-PRMT5 with BCL6 ZNF-V5 proteins. (E) RD2 domain of BCL6 interacts with the catalytically active N terminus of PRMT5 (residues 1-320).