Premium
Initiation of DNA replication at a nuclear matrix‐attached chromatin fraction
Author(s) -
Radichev Ilian,
Parashkevova Anastassia,
Anachkova Boyka
Publication year - 2005
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.20203
Subject(s) - origin recognition complex , control of chromosome duplication , eukaryotic dna replication , chromatin , dna replication , nuclear matrix , biology , pre replication complex , replication factor c , origin of replication , s phase , microbiology and biotechnology , scaffold/matrix attachment region , dna , genetics , chromatin remodeling
It is still unclear what nuclear components support initiation of DNA replication. To address this issue, we developed a cell‐free replication system in which the nuclear matrix along with the residual matrix‐attached chromatin was used as a substrate for DNA replication. We found out that initiation occurred at late G1 residual chromatin but not at early G1 chromatin and depended on cytosolic and nuclear factors present in S phase cells but not in G1 cells. Initiation of DNA replication occurred at discrete replication foci in a pattern typical for early S phase. To prove that the observed initiation takes place at legitimate DNA replication origins, the in vitro synthesized nascent DNA strands were isolated and analyzed. It was shown that they were enriched in sequences from the core origin region of the early firing, dihydrofolate reductase origin of replication ori‐β and not in distal to the origin sequences. A conclusion is drawn that initiation of DNA replication occurs at discrete sub‐chromosomal structures attached to the nuclear matrix. © 2004 Wiley‐Liss, Inc.