A previous genetic screen was designed to separate Hin recombinase mutants into distinct classes based on the stage in the recombination reaction at which they are blocked (O. Nanassy, Zoltan, and K. T. Hughes, Genetics 149:1649-1663, 1998). One class of DNA binding-proficient, recombination-deficient mutants was predicted by genetic classification to be defective in the step prior to invertaso...

The A mating type locus of Coprinus cinereus is remarkable for its extreme diversity, with over 100 different alleles in natural populations. Classical genetic studies have demonstrated that this hypervariability arises in part from recombination between two subloci of A, alpha and beta, although more recent population genetic data have indicated a third segregating sublocus. In this study, we ...

We have asked here how the remarkable variation in maize haplotype structure affects recombination. We compared recombination across a genetic interval of 9S in 2 highly dissimilar heterozygotes that shared 1 parent. The genetic interval in the common haplotype is approximately 100 kb long and contains 6 genes interspersed with gene-fragment-bearing Helitrons and retrotransposons that, together...

In all cells, genetic recombination is used to repair DNA breaks and, as a result, genetic information is exchanged between homologous DNA molecules. Discontinuities in DNA strands, specifically double-strand DNA breaks and single-strand DNA gaps, attract the enzymes responsible for the initiation of homologous recombination. In wild-type Escherichia coli, two distinct pathways are responsible ...

Bacillus subtilis protoplast fusion allows the study of the genetic recombination of an entire procaryotic genome. Protoplasts from bacterial strains marked genetically by chromosomal mutations were fused using polyethylene glycol and the regenerated cells analyzed. Recombinants represent 19.3% of heterozygotic cells; they are haploids. Individual characterization of clones show a unique partic...

Mutation and recombination are the two main forces generating genetic variation. Most of this variation may be deleterious. Because recombination can reorganize entire genes and genetic circuits, it may have much greater consequences than point mutations. We here explore the effects of recombination on models of transcriptional regulation circuits that play important roles in embryonic developm...

The RecA protein has been the most intensively studied protein involved in homologous genetic recombination, but until recently very little has been known about the molecular details of how RecA can bring two DNA molecules into juxtaposition and switch strands between them. A recent RecA-DNA crystal structure provides some striking new insights.

HE models for genetic recombination which were designed by WHITEHOUSE T(1963) and HOLLIDAY (1 964) differ in some details, but both include a stage at which two chromatids of the tetrad carry corresponding segments of hybrid DNA (a region in which the two complementary strands come from different chromatids). The models were designed to account for both reciprocal and nonreciprocal recombinatio...

Given the importance of meiotic recombination in biology, there is a need to develop robust methods to estimate meiotic recombination rates. A popular approach, called the Marey map approach, relies on comparing genetic and physical maps of a chromosome to estimate local recombination rates. In the past, we have implemented this approach in an R package called MareyMap, which includes many func...

We have observed genetic recombination between ura3( -) mutations (among them extensive deletions) carried on "episomal" (i.e., 2micro DNA-containing) plasmids and other ura3( -) alleles present at the normal chromosomal URA3 locus. The recombination frequency found was comparable to the level observed for classical mitotic recombination but was relatively insensitive to sunlamp radiation, whic...