During transcription, RNA polymerase holoenzyme binds to a gene promoter and assumes a saddle - like…
During transcription, RNA polymerase holoenzyme binds to a gene promoter and assumes a saddle - like structure. What is it's DNA-binding sequence?
AATT
$\mathrm{CACC}$
TATA
TTAA.
Solution
The DNA binding sequence for RNA polymerase is called TATA box. The TATA box is present in the eukaryotic promoter region. It is a 7-bp long regionlocated 20 bp upstream to the start point. It is surrounded by GC rich sequences. During the process of transcription, the RNA polymerase (a holoenzyme which has a core unit and a sigma factor for properinitiation oftranscription) binds to the TATA box because of which DNA assumes a saddle-like structure at this place.
Related Theory
In molecular biology, the TATA box (also called the Goldberg-Hogness box) is a sequence of DNA found in the core promoter region of genes in archaea and eukaryotes. The bacterial homolog of the TATA box is called the Pribnow box which has a shorter consensus sequence.