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Several molecular mechanisms have been proposed to account for nonconservative homologous recombination. This type of recombination is particularly efficient in Xenopus oocytes when appropriate DNA substrates are injected. To distinguish between possible models, we have investigated recombination intermediates from oocytes by direct observation in the electron microscope. Partially recombined DNA was crosslinked with a psoralen derivative after incubation in oocytes to limit the branch migration that might occur during recovery procedures and alter the structures that were initially present. Branched structures, which we interpret as intermediates, represented approximately 10% of the DNA recovered and were readily analyzed. We did not observe any structures with internal loops predicted by invasion mechanisms. The majority of intermediates had one or two single-stranded branches on product-sized molecules, as predicted for incomplete junctions in the resection-annealing mechanism. Detailed length measurements confirmed the expectations of that model. When recovered DNA was not crosslinked, or when annealed junctions were prepared in vitro, we saw branched structures that indicated the occurrence of extensive branch migration. Comparison with the crosslinked sample confirmed the effectiveness of the crosslinking in preserving structures created in the oocytes. Our results strongly support a resection-annealing mechanism of recombination in oocytes.
Baur,
Intermolecular homologous recombination in plants.
1990, Pubmed
Baur,
Intermolecular homologous recombination in plants.
1990,
Pubmed
Brouillette,
Intermolecular recombination assay for mammalian cells that produces recombinants carrying both homologous and nonhomologous junctions.
1987,
Pubmed
Carroll,
Efficient homologous recombination of linear DNA substrates after injection into Xenopus laevis oocytes.
1986,
Pubmed
,
Xenbase
Cassuto,
Mechanism for the action of lambda exonuclease in genetic recombination.
1971,
Pubmed
Cech,
Alkaline gel electrophoresis of deoxyribonucleic acid photoreacted with trimethylpsoralen: rapid and sensitive detection of interstrand cross-links.
1981,
Pubmed
Cech,
Electron microscopy of DNA crosslinked with trimethylpsoralen: test of the secondary structure of eukaryotic inverted repeat sequences.
1976,
Pubmed
Chakrabarti,
Recombination and deletion of sequences in shuttle vector plasmids in mammalian cells.
1985,
Pubmed
Church,
Genomic sequencing.
1984,
Pubmed
Cortese,
Transcription of tRNA genes in vivo: single-stranded compared to double-stranded templates.
1980,
Pubmed
,
Xenbase
Dale,
A rapid single-stranded cloning strategy for producing a sequential series of overlapping clones for use in DNA sequencing: application to sequencing the corn mitochondrial 18 S rDNA.
1985,
Pubmed
Doherty,
Genetic recombination of bacterial plasmid DNA. Physical and genetic analysis of the products of plasmid recombination in Escherichia coli.
1983,
Pubmed
Dunn,
Electron microscopic visualization of recA-DNA filaments: evidence for a cyclic extension of duplex DNA.
1982,
Pubmed
Feinberg,
A technique for radiolabeling DNA restriction endonuclease fragments to high specific activity.
1983,
Pubmed
Fishman-Lobell,
Two alternative pathways of double-strand break repair that are kinetically separable and independently modulated.
1992,
Pubmed
Folger,
Nonreciprocal exchanges of information between DNA duplexes coinjected into mammalian cell nuclei.
1985,
Pubmed
Goedecke,
Activation of a system for the joining of nonhomologous DNA ends during Xenopus egg maturation.
1992,
Pubmed
,
Xenbase
Gruss,
Nucleosome assembly in mammalian cell extracts before and after DNA replication.
1990,
Pubmed
Grzesiuk,
Recombination of DNAs in Xenopus oocytes based on short homologous overlaps.
1987,
Pubmed
,
Xenbase
Gurdon,
The use of Xenopus oocytes for the expression of cloned genes.
1983,
Pubmed
,
Xenbase
Hsieh,
Pairing of homologous DNA sequences by proteins: evidence for three-stranded DNA.
1990,
Pubmed
Jeong-Yu,
Test of the double-strand-break repair model of recombination in Xenopus laevis oocytes.
1992,
Pubmed
,
Xenbase
Kitamura,
Homologous recombination in a mammalian plasmid.
1990,
Pubmed
Lin,
Model for homologous recombination during transfer of DNA into mouse L cells: role for DNA ends in the recombination process.
1984,
Pubmed
Maryon,
Characterization of recombination intermediates from DNA injected into Xenopus laevis oocytes: evidence for a nonconservative mechanism of homologous recombination.
1991,
Pubmed
,
Xenbase
Maryon,
Degradation of linear DNA by a strand-specific exonuclease activity in Xenopus laevis oocytes.
1989,
Pubmed
,
Xenbase
Maryon,
Involvement of single-stranded tails in homologous recombination of DNA injected into Xenopus laevis oocyte nuclei.
1991,
Pubmed
,
Xenbase
McEntee,
Initiation of general recombination catalyzed in vitro by the recA protein of Escherichia coli.
1979,
Pubmed
Ozenberger,
A unique pathway of double-strand break repair operates in tandemly repeated genes.
1991,
Pubmed
Pennington,
Gene targeting in Chinese hamster ovary cells is conservative.
1991,
Pubmed
Plessis,
Site-specific recombination determined by I-SceI, a mitochondrial group I intron-encoded endonuclease expressed in the yeast nucleus.
1992,
Pubmed
Rao,
Stable three-stranded DNA made by RecA protein.
1991,
Pubmed
Register,
The direction of RecA protein assembly onto single strand DNA is the same as the direction of strand assimilation during strand exchange.
1985,
Pubmed
Revet,
Electron microscopy of AD5 replicating molecules after in vivo photocrosslinking with trioxsalen.
1981,
Pubmed
Rubnitz,
The minimum amount of homology required for homologous recombination in mammalian cells.
1984,
Pubmed
Rudin,
Efficient repair of HO-induced chromosomal breaks in Saccharomyces cerevisiae by recombination between flanking homologous sequences.
1988,
Pubmed
Seidman,
Intermolecular homologous recombination between transfected sequences in mammalian cells is primarily nonconservative.
1987,
Pubmed
Seifert,
Shuttle mutagenesis: a method of transposon mutagenesis for Saccharomyces cerevisiae.
1986,
Pubmed
Shibata,
Purified Escherichia coli recA protein catalyzes homologous pairing of superhelical DNA and single-stranded fragments.
1979,
Pubmed
Smith,
Homologous recombination in procaryotes.
1988,
Pubmed
Sugawara,
Characterization of double-strand break-induced recombination: homology requirements and single-stranded DNA formation.
1992,
Pubmed
Sun,
Extensive 3'-overhanging, single-stranded DNA associated with the meiosis-specific double-strand breaks at the ARG4 recombination initiation site.
1991,
Pubmed
Symington,
Intramolecular recombination of linear DNA catalyzed by the Escherichia coli RecE recombination system.
1985,
Pubmed
Szostak,
The double-strand-break repair model for recombination.
1983,
Pubmed
Thomas,
Recombination of DNA molecules.
1966,
Pubmed
Umlauf,
Triple-helical DNA pairing intermediates formed by recA protein.
1990,
Pubmed
Wallace,
Protein incorporation by isolated amphibian oocytes. 3. Optimum incubation conditions.
1973,
Pubmed
,
Xenbase
West,
Processing of recombination intermediates in vitro.
1990,
Pubmed
White,
Intermediates of recombination during mating type switching in Saccharomyces cerevisiae.
1990,
Pubmed
