Figure 1.

Nonconsensus protein-DNA binding free energy is statistically reduced in the yeast promoter regions. Computed probability distribution, $P(\Delta f)$, of the free-energy difference per basepair, $\Delta f=f_{\text{min}}-f_{\max }$, for each transcript from Rhee and Pugh (4), where $f_{\text{min}}$ and $f_{\max }$ are the minimal and the maximal free energy values, respectively, in the interval $(-400,400)$ around the TSS, where we defined, $\Delta f={\langle \Delta F\rangle }_{\text{TF}}/M$, and we used M = 8. $P(\Delta f)$ is computed based on 6045 transcripts from Rhee and Pugh (4). The average value, $\langle \Delta f\rangle =-0.54k_{\text{B}}T$. (Inset) Example of the computed free-energy profile, $f={\langle F\rangle }_{\text{TF}}/M$, for the CDC15 gene, with the definitions of $f_{\text{min}}$, $f_{\max }$, and $\Delta f$.