Conserved nucleosome positioning defines replication origins.
The origin recognition complex (ORC) specifies replication origin location. The Saccharomyces cerevisiae ORC recognizes the ARS (autonomously replicating sequence) consensus sequence (ACS), but only a subset of potential genomic sites are bound, suggesting other chromosomal features influence ORC binding. Using high-throughput sequencing to map ORC binding and nucleosome positioning, we show that yeast origins are characterized by an asymmetric pattern of positioned nucleosomes flanking the ACS. The origin sequences are sufficient to maintain a nucleosome-free origin; however, ORC is required for the precise positioning of nucleosomes flanking the origin. These findings identify local nucleosomes as an important determinant for origin selection and function.
Eaton
Matthew L
ML
Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA.
Galani
Kyriaki
K
Kang
Sukhyun
S
Bell
Stephen P
SP
MacAlpine
David M
DM
D015825:Chromosomes, Fungal / Q000235:genetics; D016681:Genome, Fungal / Q000235:genetics; D009707:Nucleosomes / Q000235:genetics*; D018741:Replication Origin / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D017421:Sequence Analysis
D009707:Nucleosomes