Differential paralog divergence modulates genome evolution across yeast species
A) Schematic illustrating how evolved strains were derived and analyzed by sequencing to generate copy number plots shown below. B) Copy number of relevant genomic segments surrounding the SUL1 (top) and SUL2 (bottom) loci in a representative evolved strain of S. cerevisiae. Copy number plots were calculated by sequencing-depth ratios between evolved and parental genomes in S. cerevisiae at 188 generations. Gray dots represent the per nucleotide read-depth averaged across 25bp windows. Segmentation-derived regions of equal copy number are indicated in red. Segmentation defines an ~11kb region with a copy number of 5. The region of the sulfate transporter gene SUL1 gene is shaded red. C) Sequencing-depth ratios between evolved and parental genomes in an S. uvarum clone isolated at 510 generations are plotted at relevant genomic segments surrounding the SUL1 (top) and SUL2 (bottom) loci. A large segmental amplification of an evolved clone defining a ~168kb region with a copy number of ~5 includes the locus containing the sulfate transporter gene SUL2, shaded in blue. Genes aligned at the top represent the loci in the expanded panel.