Gene expression diverges rapidly between related species, playing a key role in the evolution of new phenotypes. The extent of divergence differs greatly between genes and is correlated to promoter nucleosome organization. We hypothesized that this may be partially explained by differential sensitivity of expression to mutations in the promoter region. We measured the sensitivity of 22 yeast promoters with varying nucleosome patterns to random mutations in sequence. Mutation sensitivity differed by up to 10-fold between promoters. This difference could not be explained by the abundance of transcription factor binding sites. Rather, mutation sensitivity positively correlated with the relative occupancy of nucleosomes at the proximal promoter region. Furthermore, mutation sensitivity was reduced upon introduction of a binding site for Reb1, a factor that blocks nucleosome formation, suggesting that nucleosome organization directly regulates mutation sensitivity. Our study suggests an important role for chromatin structure in the evolution of gene expression.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Annotation Extension||Reference|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Assay||Construct||Conditions||Strain Background||Reference|