Figure 4
From: Transcriptional and structural impact of TATA-initiation site spacing in mammalian core promoters
TATA-TSS spacing influences initiation site usage. Histogram showing the distribution of the four possible dinucleotides (PyPu, PyPy, PuPy, and PuPu) at the initiation site [-1, +1] for promoters with the TATA box located at each position in the -34 to -28 range. As described previously [8], initiation sites composed of PyPu dinucleotides are the most prominent, regardless of spacing. The dinucleotide distribution is significantly different for promoters where the TATA box starts at -28. Pu, purine; Py, pyrimidine.