CpG Methylation of DNA Restricts Prereplication Complex Assembly in Xenopus Egg Extracts
AUTOR(ES)
Harvey, Kevin J.
FONTE
American Society for Microbiology
RESUMO
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 ∼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.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=193934Documentos Relacionados
- Study of the cell cycle-dependent assembly of the DNA pre-replication centres in Xenopus egg extracts.
- DNA methylation and the frequency of CpG in animal DNA.
- Nonrandom integration of retroviral DNA in vitro: effect of CpG methylation.
- Predicting aberrant CpG island methylation
- Tissue specificity and organisation of CpG methylation in calf satellite DNA I.
