Libraries were constructed using the Illumina TruSeq ChIP Sample Prep Kit (#IP-202-1012-1024). The soluble fraction of CENP-A was obtained by suspending cells in PBS with 0.5% NP-40 for 5 minutes on ice. Nuclei were then pelleted via centrifugation for 1 minute at 1000 RPM. Nuclei were once again resuspended in PBS NP-40 buffer and pelleted via centrifugation as before. Supernatants were pre-cleared via centrifugation at 12000 RPM for 10 minutes and the resulting supernatant was used in the IP. Native ChIP was performed as in (Bui et al., Epigenetics Chromatin 2017) with the exception of a longer MNase digest of 15 minutes. For each of four independent replicates (or duplicates for double knockdowns), libraries were constructed using the Illumina TruSeq ChIP Sample Prep Kit (#IP-202-1012-1024).