Question

How do enhancers increase transcription rates?

1) Enhancers bind to activators and then activators move chromatin forward
2) Enhancers bind to repressors to shut down DNA polymerase so RNA polymerase can bind
3) Enhancers bind to activators so that they can bring the proteins that begin the formation of the pre-initiation complex (PIC)
4) Enhancers bind to RNA polymerase II and allow it to start transcription at a faster rate

Answer 1

Enhancers increase transcription by binding to activators, which helps in recruiting and assembling the proteins necessary for the initiation of transcription by RNA polymerase at the gene's start site.

Step-by-step explanation:

Enhancers increase transcription rates by binding to activators so that they can bring the proteins that begin the formation of the pre-initiation complex (PIC), which is option 3 on the list provided by the student. Transcription factors bound to enhancers interact with promoter-bound factors to facilitate the recruitment of RNA polymerase to the gene's start site.

This interaction often involves bending of the DNA to allow a distant enhancer to come into proximity with the promoter, enabled by DNA bending proteins. This architecture makes it easier for RNA polymerase II to initiate transcription, hence increasing the efficiency of gene expression.