Widespread activation of developmental gene expression characterized by PRC1-dependent chromatin looping

• Published in: Science advances Vol. 6; no. 2; p. eaax4001
• Main Authors: Loubiere, V, Papadopoulos, G L, Szabo, Q, Martinez, A-M, Cavalli, G
• Format: Journal Article
• Language: English
• Published: United States American Association for the Advancement of Science (AAAS) 10.01.2020; American Association for the Advancement of Science
• Subjects: Animals; Cell Differentiation - genetics; Chromatin - metabolism; Drosophila melanogaster - embryology; Drosophila melanogaster - genetics; Enhancer Elements, Genetic - genetics; Gene Expression Regulation, Developmental; Genes, Developmental; Genetic Loci; Genetics; Imaginal Discs - metabolism; Life Sciences; Mice; Neural Stem Cells - cytology; Neural Stem Cells - metabolism; Polycomb Repressive Complex 1 - metabolism; Promoter Regions, Genetic; Protein Binding; Response Elements - genetics; SciAdv r-articles
• ISSN: 2375-2548; 2375-2548
• DOI: 10.1126/sciadv.aax4001

Polycomb repressive complexes 1 and 2 have been historically described as transcriptional repressors, but recent reports suggest that PRC1 might also support activation, although the underlying mechanisms remain elusive. Here, we show that stage-specific PRC1 binding at a subset of active promoters and enhancers during development coincides with the formation of three-dimensional (3D) loops, an increase in expression during development and repression in PRC1 mutants. Dissection of the locus indicates that PRC1-anchored loops are versatile architectural platforms that persist when surrounding genes are transcriptionally active and fine-tune their expression. The analysis of RING1B binding profiles and 3D contacts during neural differentiation in mice suggests that this role is conserved in mammals.