Genome-wide maps of nucleolus interactions in human cells using 4xAP3 DamID

We used DamID to map nucleolus interactions in human cells using a 4x tandem repeat of the nucleolar targeting sequence of AP3D1 (Scott, 2010) ("4xAP3"). These interactions are mapped in various human cell lines, including human K562 cells A DamID expression vector was created where Dam was fused to the 4xAP3 sequence described above to target to the nucleolus. Wild-type K562 cells were transduced with lentiviral constructs in more replicates, Dam-4xAP3 or Dam only and collected by three days after transduction for quantification of genome-wide methylation levels via next-generation sequencing.