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We have examined the replication patterns of ribosomal DNA plasmids in vivo and in vitro using Xenopus eggs. Plasmids carrying different parts of the Xenopus ribosomal DNA sequence were allowed to replicate either in vitro in an egg extract or in vivo after microinjection into unfertilized eggs. The replication intermediates were analyzed by the 2D gel electrophoretic technique of Brewer and Fangman (1), using original or modified electrophoresis conditions. With standard electrophoresis conditions, the patterns obtained for restriction fragments larger than 5 kb were unreliable because of artefactually distorted Y arcs and unrecognizable bubble arcs. Interpretable patterns could nevertheless be obtained using suitably modified electrophoresis parameters. Under these conditions, replication was found to initiate and terminate at multiple, random locations on each plasmid both in vivo and in vitro. However, only one or very few of these potential initiation sites are used during the replication of an individual plasmid molecule. We discuss the possible artefacts and misinterpretations that can result when the 2D electrophoresis parameters are not adapted to the size of the fragment examined. We also discuss the relevance of the random replication mode to the mechanisms and the control of DNA replication in eukaryotes.
Bakken,
Mapping of transcription initiation and termination signals on Xenopus laevis ribosomal DNA.
1982, Pubmed,
Xenbase
Bakken,
Mapping of transcription initiation and termination signals on Xenopus laevis ribosomal DNA.
1982,
Pubmed
,
Xenbase
Biamonti,
Fate of exogenous recombinant plasmids introduced into mouse and human cells.
1985,
Pubmed
Blow,
Initiation of DNA replication in nuclei and purified DNA by a cell-free extract of Xenopus eggs.
1986,
Pubmed
,
Xenbase
Blow,
Replication of purified DNA in Xenopus egg extract is dependent on nuclear assembly.
1990,
Pubmed
,
Xenbase
Blumenthal,
The units of DNA replication in Drosophila melanogaster chromosomes.
1974,
Pubmed
Botchan,
A specific replication origin in the chromosomal rDNA of Lytechinus variegatus.
1982,
Pubmed
Botchan,
Restriction analysis of the nontranscribed spacers of Xenopus laevis ribosomal DNA.
1977,
Pubmed
,
Xenbase
Bozzoni,
Replication of ribosomal DNA in Xenopus laevis.
1981,
Pubmed
,
Xenbase
Bramhill,
Duplex opening by dnaA protein at novel sequences in initiation of replication at the origin of the E. coli chromosome.
1988,
Pubmed
Brewer,
A replication fork barrier at the 3' end of yeast ribosomal RNA genes.
1988,
Pubmed
Brewer,
The localization of replication origins on ARS plasmids in S. cerevisiae.
1987,
Pubmed
Burhans,
Emetine allows identification of origins of mammalian DNA replication by imbalanced DNA synthesis, not through conservative nucleosome segregation.
1991,
Pubmed
Burhans,
Identification of an origin of bidirectional DNA replication in mammalian chromosomes.
1990,
Pubmed
Callan,
Replication of DNA in the chromosomes of eukaryotes.
1972,
Pubmed
Diffley,
The initiation of chromosomal DNA replication in eukaryotes.
1990,
Pubmed
Dubey,
Evidence suggesting that the ARS elements associated with silencers of the yeast mating-type locus HML do not function as chromosomal DNA replication origins.
1991,
Pubmed
Ellison,
Long-range interactions of multiple DNA structural transitions within a common topological domain.
1987,
Pubmed
Ferguson,
A yeast origin of replication is activated late in S phase.
1991,
Pubmed
Gasser,
Replication origins, factors and attachment sites.
1991,
Pubmed
Gaudette,
Replication forks are underrepresented in chromosomal DNA of Xenopus laevis embryos.
1986,
Pubmed
,
Xenbase
Hamlin,
Origins of replication: timing and chromosomal position.
1991,
Pubmed
Handeli,
Mapping replication units in animal cells.
1989,
Pubmed
Harland,
Regulated replication of DNA microinjected into eggs of Xenopus laevis.
1980,
Pubmed
,
Xenbase
Heinzel,
Autonomous DNA replication in human cells is affected by the size and the source of the DNA.
1991,
Pubmed
Huberman,
On the mechanism of DNA replication in mammalian chromosomes.
1968,
Pubmed
Huberman,
The in vivo replication origin of the yeast 2 microns plasmid.
1987,
Pubmed
Huberman,
Close association of a DNA replication origin and an ARS element on chromosome III of the yeast, Saccharomyces cerevisiae.
1988,
Pubmed
Jong,
DNA synthesis in yeast cell-free extracts dependent on recombinant DNA plasmids purified from Escherichia coli.
1985,
Pubmed
Krysan,
Replication initiates at multiple locations on an autonomously replicating plasmid in human cells.
1991,
Pubmed
Linskens,
Organization of replication of ribosomal DNA in Saccharomyces cerevisiae.
1988,
Pubmed
Linskens,
The two faces of higher eukaryotic DNA replication origins.
1990,
Pubmed
Linskens,
Ambiguities in results obtained with 2D gel replicon mapping techniques.
1990,
Pubmed
Martín-Parras,
Unidirectional replication as visualized by two-dimensional agarose gel electrophoresis.
1991,
Pubmed
Méchali,
Lack of specific sequence requirement for DNA replication in Xenopus eggs compared with high sequence specificity in yeast.
1984,
Pubmed
,
Xenbase
Nawotka,
Two-dimensional gel electrophoretic method for mapping DNA replicons.
1988,
Pubmed
Reeder,
rRNA synthesis in the nucleolus.
1990,
Pubmed
Schvartzman,
Evidence that replication initiates at only some of the potential origins in each oligomeric form of bovine papillomavirus type 1 DNA.
1990,
Pubmed
Shinomiya,
Analysis of chromosomal replicons in early embryos of Drosophila melanogaster by two-dimensional gel electrophoresis.
1991,
Pubmed
Stinchcomb,
Isolation and characterisation of a yeast chromosomal replicator.
1979,
Pubmed
Umek,
New beginnings in studies of eukaryotic DNA replication origins.
1989,
Pubmed
Umek,
The ease of DNA unwinding as a determinant of initiation at yeast replication origins.
1988,
Pubmed
Umek,
Thermal energy suppresses mutational defects in DNA unwinding at a yeast replication origin.
1990,
Pubmed
Vassilev,
Mapping an origin of DNA replication at a single-copy locus in exponentially proliferating mammalian cells.
1990,
Pubmed
Vassilev,
An initiation zone of chromosomal DNA replication located upstream of the c-myc gene in proliferating HeLa cells.
1990,
Pubmed
Vaughn,
Replication initiates in a broad zone in the amplified CHO dihydrofolate reductase domain.
1990,
Pubmed
Yang,
Replication of bovine papillomavirus type 1 DNA initiates within an E2-responsive enhancer element.
1990,
Pubmed