GSE104720
Analysis of chromatin accessibility in decidualizing human endometrial stromal cells
Spontaneous decidualization of the endometrium in response to progesterone signaling is confined to menstruating species, including humans and other higher primates. During this process, endometrial stromal cells (EnSCs) differentiate into specialized decidual cells that control embryo implantation. We subjected undifferentiated and decidualizing human EnSCs to Assay for Transposase Accessible Chromatin with sequencing (ATAC-seq) to map the underlying chromatin changes. A total of 185,084 open DNA loci were mapped accurately in EnSCs. Altered chromatin accessibility upon decidualization was strongly associated with differential gene expression. Analysis of 1,533 opening as well as closing chromatin regions revealed overrepresentation of DNA binding motifs for known decidual transcription factors (TFs) and identified putative new regulators. ATAC-seq footprint analysis provided evidence of TF binding at specific motifs. One of the largest footprints involved the most enriched motif, basic leucine zipper (bZIP), as part of a triple motif that also comprised the estrogen receptor- and Pax domain-binding sites. Without exception, triple motifs were located within Alu elements, suggesting a role for this primate-specific transposable element (TE) in the evolution of decidual genes. Although other TEs were generally underrepresented in open chromatin of undifferentiated EnSCs, several classes contributed to the regulatory DNA landscape that underpins decidual gene expression. Overall design: We subjected undifferentiated and decidualizing human EnSCs to Assay for Transposase Accessible Chromatin with sequencing (ATAC-seq) to map the underlying chromatin changes.