title: Defining replication origin efficiency using DNA fiber assays.
abstract: The timely duplication of eukaryotic genomes depends on the coordinated activation of thousands of replication origins distributed along the chromosomes. Origin activation follows a temporal program that is imposed by the chromosomal context and is under the control of S-phase checkpoints. Although the general mechanisms regulating DNA replication are now well-understood at the level of individual origins, little is known on the coordination of thousands of initiation events at a genome-wide level. Recent studies using DNA combing and other single-molecule assays have shown that eukaryotic genomes contain a large excess of replication origins. Most of these origins remain "dormant" in normal growth conditions but are activated when fork progression is impeded. In this review, we discuss how DNA fiber technologies have changed our view of eukaryotic replication programs and how origin redundancy contributes to the maintenance of genome integrity in eukaryotic cells.
authors.affiliation: Institute of Human Genetics, CNRS UPR 1142, 141 rue de la Cardonille, 34396, Montpellier Cedex 5, France.
authors.forename: Sandie
authors.initials: S
authors.lastname: Tuduri
authors.forename: Hélène
authors.initials: H
authors.lastname: Tourrière
authors.forename: Philippe
authors.initials: P
authors.lastname: Pasero
mesh_terms: D004247:DNA / Q000737:chemistry*; D004261:DNA Replication; D017404:In Situ Hybridization, Fluorescence; D008854:Microscopy, Electron; D018741:Replication Origin
chemical_list: D004247:DNA