Fig. 4: Intergenic expressions attributable to chance promoter activities.

a, b Frequency distribution of relative expression levels (RELs) of intergenic windows in YPD (a) or SCD (b). REL equals the expression level divided by the reference (median expression level of yeast native genes) under the same environment. Frequency is shown by bars whereas the cumulative frequency is indicated by the gray line. The vertical dashed line indicates REL = 1. Note the difference between the left and right Y-axis scales. c Fractions of barcodes or intergenic windows with RELs in YPD significantly higher than various cutoffs. For instance, the bin of 0.6 includes all barcodes or intergenic windows with RELs significantly exceeding 0.6. d Fractions of intergenic windows whose YPD expressions are attributable (blue) or unattributable (gray) to chance promoter activities. For example, the bin of 0.5–0.6 includes intergenic windows with RELs significantly higher than 0.5 but not significantly higher than 0.6. Only bins containing gray areas are shown. e Fraction of barcodes or intergenic windows with RELs significantly exceeding a cutoff in YPD that have RELs significantly exceeding the same cutoff in SCD. Symbols follow (c). Source data are provided as a Source Data file.