Differential paralog divergence modulates genome evolution across yeast species

摘要: Evolutionary outcomes depend not only on the selective forces acting upon a species, but also genetic background. However, large timescales and uncertain historical selection pressures can make it difficult to discern such important background differences between species. Experimental evolution is one tool compare evolutionary potential of known genotypes in controlled environment. Here we utilized highly reproducible adaptation Saccharomyces cerevisiae investigate whether experimental other yeast species would select for similar adaptive mutations. We evolved populations S. cerevisiae, paradoxus, mikatae, uvarum, interspecific hybrids uvarum ~200-500 generations sulfate-limited continuous culture. Wild-type cultures invariably amplify high affinity sulfate transporter gene, SUL1. while amplification SUL1 locus was detected paradoxus mikatae populations, instead selected paralog, SUL2. measured relative fitness strains bearing deletions amplifications both SUL genes from different confirming that, converse SUL2 contributes more limitation than By measuring gene expression chimeric promoter-ORF constructs, were able delineate cause this differential effect primarily promoter Our data show evidence sub-functionalization among transporters across through recent changes noncoding sequence. Furthermore, these results clear example how due paralog divergence drive genome evolution.