RT Journal Article SR Electronic T1 Multiplexed chromatin imaging reveals predominantly pairwise long-range coordination between Drosophila Polycomb genes JF bioRxiv FD Cold Spring Harbor Laboratory SP 2022.05.16.492046 DO 10.1101/2022.05.16.492046 A1 Gurgo, Julian A1 Walter, Jean-Charles A1 Fiche, Jean-Bernard A1 Houbron, Christophe A1 Schaeffer, Marie A1 Cavalli, Giacomo A1 Bantignies, Frédéric A1 Nollmann, Marcelo YR 2022 UL http://biorxiv.org/content/early/2022/05/16/2022.05.16.492046.abstract AB Polycomb (Pc) group proteins are transcriptional regulators with key roles in development, cell identity and differentiation. Pc-bound chromatin regions form repressive domains that interact in 3D to assemble repressive nuclear compartments. Here, we used multiplexed chromatin imaging to investigate whether Pc compartments involve the clustering of multiple Pc domains during Drosophila development. Notably, 3D proximity between Pc targets is rare and involves predominantly pairwise interactions. These 3D proximities are particularly enhanced in segments where Pc genes are co-repressed. In addition, segment-specific expression of Hox Pc targets leads to their spatial segregation from Pc repressed genes. Finally, non-Hox Pc targets are proximal in regions where they are co-expressed. These results indicate that long-range Pc interactions are temporally and spatially regulated during differentiation and development but do not involve clustering of multiple distant Pc genes.Competing Interest StatementThe authors have declared no competing interest.