{"database":"GEO","file_versions":[{"headers":{"Content-Type":["application/json"]},"body":{"files":{"Other":["ftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE295nnn/GSE295407/"]},"type":"primary"},"statusCode":"OK","statusCodeValue":200}],"scores":null,"additional":{"omics_type":["Other"],"species":["Mus musculus"],"gds_type":["Other"],"full_dataset_link":["https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE295407"],"repository":["GEO"],"entry_type":["GSE"],"additional_accession":[]},"is_claimable":false,"name":"Polycomb Chromatin Topology Enables Long-Range Enhancer Recruitment during Craniofacial Development [Hi-C]","description":"Little is known about how three-dimensional chromatin topology shapes mammalian craniofacial development. In mouse cranial neural crest cells, a Polycomb Repressive Complex 2 (PRC2)-dependent chromatin architecture is established before migration. This configuration maintains craniofacial gene promoters poised and connects them with distal Polycomb tethering elements, positioning promoters in spatial proximity to future long-range enhancers. Deletion of Ezh2 disrupts this early topology, causing inappropriate gene derepression in post-migratory craniofacial subpopulations where these genes are normally silenced, and failure of long-range enhancer recruitment where activation is required, thereby impairing proper gene expression. We further identify a distal Polycomb tethering element essential for Hoxa2 enhancer recruitment across topologically associating domains. Thus, Polycomb acts not only as a transcriptional repressor, but also as a chromatin-folding organizer that prepares developmental genes for later activation, by facilitating subsequent recruitment of distal active enhancers previously not in contact. Polycomb-mediated topology therefore orchestrates the transition from progenitor plasticity to precise spatiotemporal control of morphogenetic gene programs during neural crest development and face formation.","dates":{"publication":"2026/04/08"},"accession":"GSE295407","cross_references":{"GSM":["GSM8947482","GSM8947483","GSM8947484","GSM8947485","GSM8947486","GSM9561923","GSM8947487","GSM8947488"],"GPL":["19057"],"GSE":["295407"],"taxon":["Mus musculus"]}}