ChIP-Seq: Cells were crosslinked by addition of 1% formaldehyde to media at 37 C for 10 minutes, followed by glycine quenching and 2x washing in PBS. Nuclei were isolated by hypotonic buffer lysis, and chromatin was fragmented with a Branson sonifier in a 1% SDS-containing lysis buffer. Samples were diluted 1:10 and chromatin complexes containing the target of interest were isolated by immunoprecipitation, followed by reverse crosslinking and DNA purification by SPRI. For input samples, 1:10 diluted sonicated chromatin (whole cell extract; wce) was added directly to the reverse crosslinking step without immunoprecipitation. ChIP-Seq: Purified ChIP or input DNA was end-repaired and A-tailed. Illumina barcoded adaptors were ligated and PCR amplified. Final library was isolated by double SPRI purification (sequential reverse and forward SPRI) and paired-end sequenced (38 bp x 2) on Illumina NextSeq.