Core promoter elements of eukaryotic genes have a highly distinctive mechanical property

In spite of the abundant data on DNA sequence, the mechanical aspects of promoter DNA remain poorly understood. We classified 1871 human and 196 mouse RNA polymerase II promoters and investigated average flexibility profiles of the human promoters containing either a TATA box or an initiator (Inr) sequence only. Here, we show that TATA boxes and Inr sequences have a common anomalous mechanical property: they are comprised of distinctively flexible and rigid sequences, compared with the other parts of the promoter region. The +2 position in the Inr consensus sequence does not favor adenine to keep the high flexibility and thus this position is more accurately represented as 'T, G, C>A'. Additionally, it was also found that DNA region upstream of TATA box or Inr sequence is more rigid than region downstream of each element. These properties may function as a marker for recognition by TATA-binding protein and Inr-binding protein.