Work

CpG Methylation of DNA Restricts Prereplication Complex Assembly in Xenopus Egg Extracts

Year: 2003

Type: article

Abstract: In a Xenopus egg replication system, the origin recognition complex (ORC) does not bind to CpG methylated DNA and DNA replication is inhibited. Insertion of low density CpG DNA of at least 1.2 kb into methylated plasmids rescues both replication and ORC binding. Using this pseudo-origin, we find that ORC binding is restricted to low-CpG-density DNA; however, MCM is loaded onto both weakly and highly methylated DNA and occupies at least approximately 2 kb of DNA. Replication initiates coincident with MCM, and even the most distally bound MCM is associated with sites of replication initiation. These results suggest that in metazoans MCM is loaded onto and initiates replication over a large region distant from ORC.

Source: Molecular and Cellular Biology

DOI: 10.1128/mcb.23.19.6769-6779.2003

Authors: Kevin J. Harvey, John Newport

Institution: University of California San Diego

Language: English

Topic: Epigenetics and DNA Methylation

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: National Institutes of Health, National Institute of General Medical Sciences