What enhances the strength of a promoter according to the interaction of RNAP?

The strength of a promoter is significantly enhanced by the interaction of RNA polymerase (RNAP) with specific elements within the promoter region, particularly through what is known as the discriminator element. This element is crucial because it helps stabilize the binding of RNAP to the promoter. When RNAP binds effectively, it initiates transcription more efficiently.

The discriminator element interacts with the RNAP and plays a key role in the formation of the open complex, allowing the transcription machinery to effectively commence the process of RNA synthesis. This interaction is integral when considering the full functionality of a promoter, transcending merely the presence of strong enhancer regions or the alignment of consensus sequences.

While consensus sequence alignment is important, it is not sufficient by itself to enhance promoter strength without the effective binding and interaction of RNAP, which is facilitated by the discriminator. Strong enhancer regions, while they can boost transcription from a distance, do not directly interact at the core promoter level like the discriminator does. Moreover, stating that there is no interaction at all contradicts the fundamental mechanics of transcription initiation, where the interactions between RNAP and various promoter elements are essential for successful transcription initiation.