Saccharomyces cerevisiae BYxYJM segregants raw sequence reads. Saccharomyces cerevisiae

In this study, we show that substantial heterogeneity underlies a model phenotype—haploid invasive growth—in Saccharomyces cerevisiae across genotypes and environments. We find that at least five distinct regulatory architectures specify related phenotypes across genetic backgrounds and environments in a single pairwise cross. Most of the heterogeneity observed in our study appears to be due to regulatory rewiring involving multiple signaling cascades that can activate the same phenotypically important target gene. However, we also show heterogeneity arises when distinct genes that are regulated in different ways result in comparable phenotypic effects.