Figure 7

For genes with a single active promoter, there is a strong tendency for that promoter to be located at the 5' end of the annotated gene, marked as "upstream", versus the 3'-end of the gene which is marked as "downstream" (A). Similar trends are observed in the case of genes with two active promoters where neither is affected by E2 treatment. Here, one of the promoters is likely to be at the 5' end of the gene, while the other promoter can occur anywhere else along the gene length with roughly equal probability (B). A different pattern is observed in genes with two active promoters where one is affected by E2 treatment (either activated or inactivated). In this case we can see that, as before, the upstream active promoter is likely to be located at the 5' end of the gene, but the downstream promoter is strongly biased towards the 3' end of the gene (C).