Abo Bibliothek: Guest
Digitales Portal Digitale Bibliothek eBooks Zeitschriften Referenzen und Berichte Forschungssammlungen
Critical Reviews™ in Eukaryotic Gene Expression
Impact-faktor: 1.841 5-jähriger Impact-Faktor: 1.927 SJR: 0.649 SNIP: 0.516 CiteScore™: 1.96

ISSN Druckformat: 1045-4403
ISSN Online: 2162-6502

Critical Reviews™ in Eukaryotic Gene Expression

DOI: 10.1615/CritRevEukarGeneExpr.v9.i3-4.200
pages 353-361

DNA Replication and Nuclear Organization: Prospects for a Soluble In Vitro System

Daniela S. Dimitrova
Department of Biochemistry and Molecular Biology, S.U.N.Y. Health Science Center, 750 East Adams Street, Syracuse, NY 13210
David M. Gilbert
Department of Biochemistry and Molecular Biology, S.U.N.Y. Health Science Center, 750 East Adams Street, Syracuse, NY 13210

ABSTRAKT

The role of nuclear structure in the replication of eukaryotic DNA has been the subject of debate for many decades. The recent demonstration that once-per-cell-cycle replication can take place in vitro without a nucleus, providing sufficiently high concentrations of replication factors are supplied, suggests that one role of the nucleus is to concentrate essential factors. This important finding has paved the way for the establishment of a purified biochemical system for replication of eukaryotic DNA. However, this soluble system, derived from Xenopus egg extracts, initiates replication within any DNA sequence and does not recapitulate the spatial and temporal regulation of DNA replication that is observed in most cells. In both Xenopus and Drosophila embryos, site-specific initiation of replication is not observed until after nuclei become transcriptionally active at the blastula stage of development. Furthermore, programmed changes in both the locations of origins and the time during S-phase at which sequences are replicated accompany key stages of metazoan development. Recent findings indicate that these changes correlate with changes in nuclear organization and that the spatial and temporal program for replication is established early in Gl-phase when nuclei are structurally and functionally reorganized after mitosis.