Cells were washed in PBS and fixed for 15 min in 1% of formaldehyde (Sigma) in PBS. Glycin was added (125 mM glycin) and cells were incubated for 5 min. Cells were washed with PBS and scraped in SDS buffer (100mM NaCl, 50mM Tris pH 8.1, 5mM EDTA, 0.2% NaN3, 0.5% (w/v) SDS). Cells were cleared by centrifugation and the pellet resuspended in cold ChIP buffer (100mM NaCl, 133mM Tris pH 8.0, 5 mM EDTA, 0.2% NaN3, 0.67% SDS, 1.67% Triton X-100) supplemented with protease inhibitors (cOmplete Protease Inhibitor Cocktail Tablets, Roche) and phosphatase inhibitors (50 mM NaF, 1 mM β-GP, 1 mM NaV). All following steps were performed on ice, if not specified differently. Chromatin was sonicated to an average length of 200-400bp, pre-cleared with proteinG-sepharose beads (blocked with 0.5% E. coli tRNA (Sigma) and 0.5% BSA). 10µg of the following antibodies were used per ChIPseq reaction: Myc N262 (Santa Cruz, sc-764), RNAPII N20 (Santa Cruz, sc-899). The antibody was incubated overnight with 500-1000µl of chromatin. Blocked proteinG-sepharose beads were added, incubated for 2-3h and washed as follows: 3x mixed micelle buffer (150 mM NaCl, 20 mM Tris pH 8.1, 5 mM EDTA, pH 8.0, 5.2% sucrose, 0.02% NaN3, 1% Triton X-100, 0.2% SDS), 2x buffer 500 (50 mM HEPES pH 7.5, 0.1% sodium deoxycholate, 1 mM EDTA, 500 mM NaCl, 1% Triton X-100, 0.2% NaN3), 2x LiCl/detergent buffer (10 mM Tris pH 8.0, 0.5% sodium deoxycholate, 1 mM EDTA, 250 mM LiCl, 0.5% NP-40, 0.2% NaN3) and once in TE. DNA:protein crosslinking was reverted overnight (2% SDS in TE, 65°C), DNA purified using QiaQuick columns (Qiagen) and quantified using PicoGreen (Invitrogen). 2-5 ng of ChIP DNA were used for ChIPseq library preparation as described in (Blecher-Gonen et al., Nat Protoc, 2013) and sequenced with the Illumina HiSeq sequencer according to the manufacturer.