title: 3D chromatin conformation correlates with replication timing and is conserved in resting cells.
abstract: Although chromatin folding is known to be of functional importance to control the gene expression program, less is known regarding its interplay with DNA replication. Here, using Circular Chromatin Conformation Capture combined with high-throughput sequencing, we identified megabase-sized self-interacting domains in the nucleus of a human lymphoblastoid cell line, as well as in cycling and resting peripheral blood mononuclear cells (PBMC). Strikingly, the boundaries of those domains coincide with early-initiation zones in every cell types. Preferential interactions have been observed between the consecutive early-initiation zones, but also between those separated by several tens of megabases. Thus, the 3D conformation of chromatin is strongly correlated with the replication timing along the whole chromosome. We furthermore provide direct clues that, in addition to the timing value per se, the shape of the timing profile at a given locus defines its set of genomic contacts. As this timing-related scheme of chromatin organization exists in lymphoblastoid cells, resting and cycling PBMC, this indicates that it is maintained several weeks or months after the previous S-phase. Lastly, our work highlights that the major chromatin changes accompanying PBMC entry into cell cycle occur while keeping largely unchanged the long-range chromatin contacts.
authors.affiliation: Laboratoire Joliot-Curie, Ecole Normale Supérieure de Lyon, CNRS, F-69007 Lyon, France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Moindrot
authors.forename: Benjamin
authors.initials: B
authors.lastname: Audit
authors.forename: Petra
authors.initials: P
authors.lastname: Klous
authors.forename: Antoine
authors.initials: A
authors.lastname: Baker
authors.forename: Claude
authors.initials: C
authors.lastname: Thermes
authors.forename: Wouter
authors.initials: W
authors.lastname: de Laat
authors.forename: Philippe
authors.initials: P
authors.lastname: Bouvet
authors.forename: Fabien
authors.initials: F
authors.lastname: Mongelard
authors.forename: Alain
authors.initials: A
authors.lastname: Arneodo
mesh_terms: D002460:Cell Line; D002478:Cells, Cultured; D002843:Chromatin / Q000737:chemistry*; D042522:DNA Replication Timing; D056426:Genetic Loci; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000502:physiology; D017422:Sequence Analysis, DNA
chemical_list: D002843:Chromatin