Nuclei isolations were lysed and sonicated to shear chromatinbefore immunopurification of crosslined DNA/protein complexes. ChIP-isolated DNA was pooled (three technical replicates done in parallel from each of two independent biological replicates) and fragments were processed to blunt ends followed by A-tailing to facilitate ligation of Illumina oligo adapters. PCR amplification was run for 12-14 cycles with primers complementary to adapter sequence to amplify the pool of ChIP DNA with addition of the adapter sequence. PCR products in the range of 200-300 bp were isolated by agarose gel electrophoresis followed by gel extraction.