The Eukaryotic Promoter Region

The promoter is a major regulator of gene expression that contains binding sites for RNA polymerase, the enzyme responsible for transcription, and transcription factors, that facilitate or inhibit the binding of RNA polymerase. 

The promoter region is mostly located upstream of the gene it regulates. It has distinct structural features, such as a curved structure with the ability to bend when transcriptional regulators bind and low thermodynamic stability due to the presence of AT-rich regions.  

In eukaryotes, this transcriptional control region is more complex than in prokaryotes. In addition to the core promoter, eukaryotic genes have many additional cis-regulatory sequences that transcription factors can bind.

Prokaryotic RNA polymerase requires a sigma factor to bind to the promoter, whereas eukaryotic RNA polymerases require several such regulators. 

Additionally, the three different RNA polymerases in eukaryotes that bind to distinct promoters, require different transcriptional regulators. 

The core eukaryotic promoter contains several signature motifs that work together in various combinations to allow RNA polymerase to bind. 

The TATA box is highly conserved across organis