Lysates were precleared with Protein G Dynabeads. Complexes were then isolated with 7µg anti-Blimp1 monoclonal antibody (Novus, clone 3H2-E8) linked to Protein G Dynabeads. Sequencing libraries were prepared using the Illumina ChIP-seq DNA Sample Prep Kit. Libraries were size selected at ~200bp and four libraries were multiplexed per lane on a HiSeq 2500.