ChIP-seq analysis of subunits of meiotic cohesin complexes (mei-Cohesins) in transgenic human cancer cell lines

The study involved chromatin IP analyzed by high-throughput sequencing analysis using stable transgenic human cancer cell lines, which express Tet-inducible combinations of mei-cohesin subunits. The following individual genes and combinations of mei-cohesin subunits were expressed in human cells : STAG3, SMC1beta, STAG3+SMC1beta+REC8, and STAG3+SMC1beta+RAD21L The goal of the study was to investigate the epigenomic properties of somatic cells in response to the induction of mei-cohesin subunits using Tet-on inducible transgenes activated by an rtTA transgene and doxycicline. Overall design: The K562 (ATCC® CCL-243™), hTERT RPE-1 (ATCC® CRL-4000™), or DLD-1 (ATCC® CCL-221™) cell lines, were first stably infected with rtTA, followed by Tet-On-STAG3, Tet-On-SMC1beta, Tet-On-REC8, and Tet-On RAD21L lentiviruses. In order to generate multi-transgenic cells that model the 4-subunit mei-cohesin holocomplexes, i.e. REC8 and RAD21L-based, the Tet-On-STAG3+Tet-On-SMC1beta cells were separately infected with Tet-On-REC8 and Tet-On-RAD21L lentiviruses, to generate two triple transgenic cell lines. The populations of transgenic cells selected for marker drug-resistance were cloned to generate single transgenic clones used for ChIP-seq experiments.