title: Genome-wide analysis of re-replication reveals inhibitory controls that target multiple stages of replication initiation.
abstract: DNA replication must be tightly controlled during each cell cycle to prevent unscheduled replication and ensure proper genome maintenance. The currently known controls that prevent re-replication act redundantly to inhibit pre-replicative complex (pre-RC) assembly outside of the G1-phase of the cell cycle. The yeast Saccharomyces cerevisiae has been a useful model organism to study how eukaryotic cells prevent replication origins from reinitiating during a single cell cycle. Using a re-replication-sensitive strain and DNA microarrays, we map sites across the S. cerevisiae genome that are re-replicated as well as sites of pre-RC formation during re-replication. Only a fraction of the genome is re-replicated by a subset of origins, some of which are capable of multiple reinitiation events. Translocation experiments demonstrate that origin-proximal sequences are sufficient to predispose an origin to re-replication. Origins that reinitiate are largely limited to those that can recruit Mcm2-7 under re-replicating conditions; however, the formation of a pre-RC is not sufficient for reinitiation. Our findings allow us to categorize origins with respect to their propensity to reinitiate and demonstrate that pre-RC formation is not the only target for the mechanisms that prevent genomic re-replication.
authors.affiliation: Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Robyn E
authors.initials: RE
authors.lastname: Tanny
authors.forename: David M
authors.initials: DM
authors.lastname: MacAlpine
authors.forename: Hannah G
authors.initials: HG
authors.lastname: Blitzblau
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Bell
mesh_terms: D002453:Cell Cycle / Q000235:genetics; D004261:DNA Replication / Q000235:genetics*; D016681:Genome, Fungal; D008954:Models, Biological; D020411:Oligonucleotide Array Sequence Analysis; D018741:Replication Origin / Q000235:genetics / Q000502:physiology*; D016196:S Phase / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics*