Chromatin extract protocol was as described in Nègre N, Brown CD, Ma L, Bristow CA et al. A cis-regulatory map of the Drosophila genome. Nature 2011 Mar 24;471(7339):527-31. PMID: 21430782 Nextera libraries were made as described in Nègre N, Brown CD, Ma L, Bristow CA et al. A cis-regulatory map of the Drosophila genome. Nature 2011 Mar 24;471(7339):527-31. PMID: 21430782