Chromatin from cross-linked cells (1% formaldehyde, 20 min) was sonicated, incubated overnight with the indicated antibodies in RIPA buffer, precipitated with protein G/A-Sepharose and cross-linkage of the co-precipitated DNA-protein complexes was reversed. Libraries were prepared using the NEBNext® Ultra™ DNA Library Prep Kit for Illumina (New England Biolabs) and sequenced on the Solexa HiSeq 2000 sequencer (Illumina) according to manufacturer's instructions.