Recently, a new type of hybrids resulting from the hybridization between S. cerevisiae and S. kudriavzevii were described. These strains exhibit physiological properties of potential biotechnological interest. A preliminary characterization of these hybrids showed a trend to reduce the S. kudriavzevii fraction of the hybrid genome. We characterized the genomic constitution of several wine S. cerevisiae x S. kudriavzevii strains by using a combined approach based on the RFLP analysis of gene regions, comparative genome hybridizations with S. cerevisiae DNA arrays, ploidy analysis and gene dose determination by quantitative real-time PCR. The high similarity in the genome structure of the S. cerevisiae x S. kudriavzevii hybrids under study indicates they originated from a single hybridization event. After hybridization, the hybrid genome underwent extensive chromosomal rearrangements, including chromosome losses and the generation of chimerical chromosomes by non-reciprocal recombination between homeologous chromosomes. These non-reciprocal recombinations between homeologous chromosomes occurred in highly conserved regions, such as Ty LTRs, rRNA regions, and conserved protein-coding genes. This study supports the hypothesis that chimerical chromosomes may have been generated by a similar mechanism to the recombination-mediated chromosome loss acting during the meiosis in Saccharomyces hybrids. As a result of the selective processes acting during fermentation, hybrid genomes maintained the S. cerevisiae genome but reduced the S. kudriavzevii fraction.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Reference||Annotation Extension|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Conditions||Strain||Source||Reference|