Chapter 14: Eukaryotic Protein-coding Genes have a Core Promoter and Regulatory Elements

What are the three main features found in most promoters of protein-coding genes?

Regulatory elements, a TATA box, and a transcriptional start site.

What is the core promoter?

A short DNA sequence necessary to start transcription, containing the TATAAA sequence (TATA box) and the start site where transcription begins.

Where is the TATA box located in relation to the transcriptional start site?

The TATA box is located 25 base pairs above the transcriptional start site.

What is the effect of regulatory elements on transcription?

Regulatory elements influence the rate of transcription by being recognized by transcription factors.

What is the role of enhancers in transcription?

Enhancers are activating sequences that stimulate transcription, preventing low levels of basal transcription.

How do silencers affect transcription?

Silencers inhibit transcription.

What are cis-acting elements?

DNA sequences that act on a specific gene and are always located on the same chromosome as the gene they affect.

What are trans-acting factors?

Proteins, such as transcription factors, that bind to regulatory sequences and can be encoded by genes located far from the core promoter.

What is basal transcription?

Low levels of transcription produced by the core promoter.

What is the significance of the distance of regulatory elements from the core promoter?

Distance does not necessarily equate to the effect on RNA polymerase efficacy.