GSE19837
Polygenic and directional regulatory evolution across pathways in Saccharomyces
We assess the prevalence of polygenic evolution in pathways between the yeasts S. cerevisiae and S. bayanus.  We first established short-read sequencing methods to detect cis-regulatory variation in a diploid hybrid between the species.  We then formulated an analytic strategy to test for the scenario in which selective pressure in one species, to increase or decrease the activity of a pathway, has driven the accumulation of cis-regulatory variants that act in the same direction on gene expression.  Application of this test revealed a variety of yeast pathways with evidence for directional regulatory evolution. Overall design: Measurement of allele-specific expression of each ortholog in a diploid hybrid between Saccharomyces species