Horizontal Gene Transfer and Introgression: key mechanisms of adaptation of yeast to its ecological niches

摘要: Horizontal gene transfer (HGT) and introgression are increasingly recognized as a prominent source of adaptation in eukaryotes. Over the past decade, several cases HGT from prokaryotes to yeast Saccharomyces strains have been demonstrated. In addition, we recently identified eukaryote-to-eukaryote transfers some them shown be involved S. cerevisiae environmental conditions (1;2;3). Three large genomic regions, (A, B C), were acquired by wine yeasts more distant species (1;3). The Zygosaccharomyces bailii Torulaspora microellipsoides, found fermentations, donors regions C, respectively We obtained evidence for amplification region (17 kb) genome (4). organization this differ considerably between identification an autonomously replicating sequence functional strongly suggest expansion mechanism genomes involving extrachromosomal circular DNA molecule. also showed that C undergone rearrangements carries genes playing key role nitrogen-limited fermentation environment (3). analysis 82 various ecological origins allowed 33 or which proposed potential using phylogenetic topology test. Among these events, observed, replacement GAL cluster cheese enables faster switch glucose galactose improves growth speed media containing mix two hexoses such fermented milk products. These data support vision customized associated specific niches highlight fungal their environments. 1. Novo et al. 2009, PNAS, 106: 16333-16338. 2. Damon al 2011, ISME Journal 9: 67. 3. Marsit 2015, Mol. Biol. Evol., 32:1695–1707 4. Galeote PLoS One 6: e17872.