OriDB Curated Paper

Genome-wide distribution of DNA replication origins at A+T-rich islands in Schizosaccharomyces pombe.

Mónica Segurado, Alberto de Luis, Francisco Antequera

EMBO Rep. (2003), 4(11):1048-53PubMed | PubMed Central | EMBO Rep.

Genome-wide analysis of replication dynamics requires the previous identification of DNA replication origins (ORIs). However, variability among the ORIs makes it difficult to predict their distribution across the genome on the basis of their sequence. We report here that ORIs in Schizosaccharomyces pombe coincide with discrete chromosomal A+T-rich islands of up to 1 kb long that are characterized by a distinctive A+T content that clearly differentiates them from the rest of the genome. Genome-wide analysis has enabled us to identify 384 of these regions, which predicts the position of most ORIs in the genome, as shown by functional replication analyses. A+T-rich islands occur at the mating locus, centromeres and subtelomeric regions at a density that is approximately fourfold higher than elsewhere in the genome, which suggests a link between the origin recognition complex (ORC) and transcriptional silencing in these regions. The absence of consensus elements in A+T-rich islands implies that different sequences can target the ORC to different ORIs.

OriDB annotation of this paper:

ARS assay

None curated.

2D gel

None curated.

ChIP of replication origin proteins

None curated.

Replication timing

None curated.

Replication in hydroxyurea

None curated.

Predicted origins

None curated.

Confirmed sequence element

None curated.

Predicted sequence element

None curated.