Incipient balancing selection through adaptive loss of aquaporins in natural Saccharomyces cerevisiae populations.

ABSTRACT: A major goal in evolutionary biology is to understand how adaptive evolution has influenced natural variation, but identifying loci subject to positive selection has been a challenge. Here we present the adaptive loss of a pair of paralogous genes in specific Saccharomyces cerevisiae subpopulations. We mapped natural variation in freeze-thaw tolerance to two water transporters, AQY1 and AQY2, previously implicated in freeze-thaw survival. However, whereas freeze-thaw-tolerant strains harbor functional aquaporin genes, the set of sensitive strains lost aquaporin function at least 6 independent times. Several genomic signatures at AQY1 and/or AQY2 reveal low variation surrounding these loci within strains of the same haplotype, but high variation between strain groups. This is consistent wit

SUBMITTER: Will JL 

PROVIDER: S-EPMC2848549 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature