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 Julian Gurgo A1 Jean-Charles Walter A1 Jean-Bernard Fiche A1 Christophe Houbron A1 Marie Schaeffer A1 Giacomo Cavalli A1 Frédéric Bantignies A1 Marcelo Nollmann 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.