Figure 1.

Fraction of Gene Pairs Sharing a Common Transcription Factor Binder vs. Correlation Coefficient In this figure each point represents a ratio – the denominator is the number of gene pairs where correlation in expression profile is between x and x+.01 and the numerator is the number of those gene pairs that share a common transcription factor. The actual yeast data is represented by blue ● and the control data (where the mapping between genes and promoters is permuted) by red ■. The observed fraction of gene pairs sharing a common transcription factor increases when the correlation between the expression profiles of the two genes is high.