Lysates were clarified from sonicated nuclei and histone-DNA complexes were isolated with antibody. DNA end repair was performed using an Epicenter End-It kit (Lucigen ER0720), according to manufacturer's instructions and column purified in a Zymo Minelute column (Zymo D4013). A-tails were added by incubating DNA in 1x NEB buffer 2 (New England Biolabs B7002S) with the addition of 200uM dATP and 7.5 units Klenow (exo-) (New England Biolabs M0212L) at 37 degrees for 45 minutes. NEB Next adaptors (New England Biolabs E7337A) were ligated using an NEB quick ligation kit (New England Biolabs M2200L) at benchtop temperature for 30 minutes followed by treatment with 2uL USER enzyme (New England Biolabs M5505L) for 15 minutes at 37°C. DNA was purified using a two-step SPRI bead protocol (from Rohland/Reich; Genome Research), resulting in purification of DNA fragments between 200-800 bp.