1
|
Smith OK, Kim R, Fu H, Martin MM, Lin CM, Utani K, Zhang Y, Marks AB, Lalande M, Chamberlain S, Libbrecht MW, Bouhassira EE, Ryan MC, Noble WS, Aladjem MI. Distinct epigenetic features of differentiation-regulated replication origins. Epigenetics Chromatin 2016; 9:18. [PMID: 27168766 PMCID: PMC4862150 DOI: 10.1186/s13072-016-0067-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 04/25/2016] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Eukaryotic genome duplication starts at discrete sequences (replication origins) that coordinate cell cycle progression, ensure genomic stability and modulate gene expression. Origins share some sequence features, but their activity also responds to changes in transcription and cellular differentiation status. RESULTS To identify chromatin states and histone modifications that locally mark replication origins, we profiled origin distributions in eight human cell lines representing embryonic and differentiated cell types. Consistent with a role of chromatin structure in determining origin activity, we found that cancer and non-cancer cells of similar lineages exhibited highly similar replication origin distributions. Surprisingly, our study revealed that DNase hypersensitivity, which often correlates with early replication at large-scale chromatin domains, did not emerge as a strong local determinant of origin activity. Instead, we found that two distinct sets of chromatin modifications exhibited strong local associations with two discrete groups of replication origins. The first origin group consisted of about 40,000 regions that actively initiated replication in all cell types and preferentially colocalized with unmethylated CpGs and with the euchromatin markers, H3K4me3 and H3K9Ac. The second group included origins that were consistently active in cells of a single type or lineage and preferentially colocalized with the heterochromatin marker, H3K9me3. Shared origins replicated throughout the S-phase of the cell cycle, whereas cell-type-specific origins preferentially replicated during late S-phase. CONCLUSIONS These observations are in line with the hypothesis that differentiation-associated changes in chromatin and gene expression affect the activation of specific replication origins.
Collapse
Affiliation(s)
- Owen K. Smith
- />DNA Replication Group, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 USA
| | - RyanGuk Kim
- />In Silico Solutions, Falls Church, VA 22033 USA
| | - Haiqing Fu
- />DNA Replication Group, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 USA
| | - Melvenia M. Martin
- />DNA Replication Group, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 USA
| | - Chii Mei Lin
- />DNA Replication Group, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 USA
| | - Koichi Utani
- />DNA Replication Group, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 USA
| | - Ya Zhang
- />DNA Replication Group, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 USA
| | - Anna B. Marks
- />DNA Replication Group, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 USA
| | - Marc Lalande
- />Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, CT 06032 USA
| | - Stormy Chamberlain
- />Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, CT 06032 USA
| | - Maxwell W. Libbrecht
- />Department of Computer Science and Engineering, University of Washington, Seattle, WA 98195 USA
| | - Eric E. Bouhassira
- />Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY 10461 USA
| | | | - William S. Noble
- />Department of Computer Science and Engineering, University of Washington, Seattle, WA 98195 USA
- />Department of Genome Sciences, University of Washington, Seattle, WA 98195 USA
| | - Mirit I. Aladjem
- />DNA Replication Group, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 USA
| |
Collapse
|
2
|
Boulos RE, Drillon G, Argoul F, Arneodo A, Audit B. Structural organization of human replication timing domains. FEBS Lett 2015; 589:2944-57. [PMID: 25912651 DOI: 10.1016/j.febslet.2015.04.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 04/09/2015] [Accepted: 04/10/2015] [Indexed: 12/16/2022]
Abstract
Recent analysis of genome-wide epigenetic modification data, mean replication timing (MRT) profiles and chromosome conformation data in mammals have provided increasing evidence that flexibility in replication origin usage is regulated locally by the epigenetic landscape and over larger genomic distances by the 3D chromatin architecture. Here, we review the recent results establishing some link between replication domains and chromatin structural domains in pluripotent and various differentiated cell types in human. We reconcile the originally proposed dichotomic picture of early and late constant timing regions that replicate by multiple rather synchronous origins in separated nuclear compartments of open and closed chromatins, with the U-shaped MRT domains bordered by "master" replication origins specified by a localized (∼200-300 kb) zone of open and transcriptionally active chromatin from which a replication wave likely initiates and propagates toward the domain center via a cascade of origin firing. We discuss the relationships between these MRT domains, topologically associated domains and lamina-associated domains. This review sheds a new light on the epigenetically regulated global chromatin reorganization that underlies the loss of pluripotency and the determination of differentiation properties.
Collapse
Affiliation(s)
- Rasha E Boulos
- Université de Lyon, F-69000 Lyon, France; Laboratoire de Physique, CNRS UMR5672, Ecole Normale Supérieure de Lyon, F-69007 Lyon, France
| | - Guénola Drillon
- Université de Lyon, F-69000 Lyon, France; Laboratoire de Physique, CNRS UMR5672, Ecole Normale Supérieure de Lyon, F-69007 Lyon, France
| | - Françoise Argoul
- Université de Lyon, F-69000 Lyon, France; Laboratoire de Physique, CNRS UMR5672, Ecole Normale Supérieure de Lyon, F-69007 Lyon, France
| | - Alain Arneodo
- Université de Lyon, F-69000 Lyon, France; Laboratoire de Physique, CNRS UMR5672, Ecole Normale Supérieure de Lyon, F-69007 Lyon, France
| | - Benjamin Audit
- Université de Lyon, F-69000 Lyon, France; Laboratoire de Physique, CNRS UMR5672, Ecole Normale Supérieure de Lyon, F-69007 Lyon, France.
| |
Collapse
|