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High-throughput mapping of origins of replication in human cells.

ABSTRACT: Mapping origins of replication has been challenging in higher eukaryotes. We have developed a rapid, genome-wide method to map origins of replication in asynchronous human cells by combining the nascent strand abundance assay with a highly tiled microarray platform, and we validated the technique by two independent assays. We applied this method to analyse the enrichment of nascent DNA in three 50-kb regions containing known origins of replication in the MYC, lamin B2 (LMNB2) and haemoglobin beta (HBB) genes, a 200-kb region containing the rare fragile site, FRAXA, and a 1,075-kb region on chromosome 22; we detected most of the known origins and also 28 new origins. Surprisingly, the 28 new origins were small in size and located predominantly within genes. Our study also showed a strong correlation between origin replication timing and chromatin acetylation.

SUBMITTER: Lucas I

PROVIDER: S-EPMC1978075 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature

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High-throughput mapping of origins of replication in human cells.

Lucas Isabelle I Palakodeti Aparna A Jiang Yanwen Y Young David J DJ Jiang Nan N Fernald Anthony A AA Le Beau Michelle M MM

EMBO reports 20070713 8

Mapping origins of replication has been challenging in higher eukaryotes. We have developed a rapid, genome-wide method to map origins of replication in asynchronous human cells by combining the nascent strand abundance assay with a highly tiled microarray platform, and we validated the technique by two independent assays. We applied this method to analyse the enrichment of nascent DNA in three 50-kb regions containing known origins of replication in the MYC, lamin B2 (LMNB2) and haemoglobin bet ...[more]

PMID: 17668008

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High resolution mapping of DNA replication origins in human genome

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Project description:Mapping origins of replication has been challenging in higher eukaryotes. We have developed a rapid, genome-wide method to map origins in asynchronous human cells by combining the nascent strand abundance assay with a highly-tiled microarray platform, and we validated the technique by two independent assays. We applied this method to analyze the enrichment of nascent DNA in three 50 kb regions containing known origins of replication in the MYC, LMNB2, and HBB genes, a 200 kb region containing the rare fragile site, FRAXA, and a 1075 kb region on chromosome 22, and detected most of the known origins, as well as 28 new origins. Surprisingly, the 28 new origins were small in size, and predominantly located within genes. Our study also revealed a strong correlation between origin replication timing and chromatin acetylation. Keywords: origin mapping, nascent strand DNA, histone acetylaction mapping, ChIP-chip

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Mapping origins of replication in Arabidopsis thaliana

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