Figure 9.

Exploration of the effects of TATA-TBP interaction strength on tissue specificity. We investigated possible dependencies between tissue specificity measured by relative entropy and three aspects of TATA-TBP interaction potential in the -40 to -19 region of each promoter: (a) the predicted TATA box with the highest score fulfilling the score threshold criteria defined in Materials and methods; (b) the sum of all predicted TATA boxes each fulfilling the specified score criteria; and (c) the predicted TATA box with the highest score fulfilling certain score threshold criteria, given TATA box location. For clarity, each plot in panel c corresponds to one type of TATA-TSS spacing, and can be considered a subset of the data points in panel a. The subdivision of the TATA-containing promoters into the different TATA-TSS spacing classes confers no additional support for a significant relation between TBP-TATA interaction strength and transcriptional specificity. In combination with panel a, this strongly suggests that TATA-TSS distance is more strongly linked to tissue specificity than the TATA-TBP interaction strength within TATA-driven core promoters. TBP, TATA box binding protein; TSS, transcription start site.