Promoter

Definition

A promoter is a DNA sequence that initiates gene transcription by providing a binding site for RNA polymerase. It is essential for the regulation and expression of genes.

5 Must Know Facts For Your Next Test

1. Promoters are located upstream of the coding sequence of a gene.
2. The promoter region includes specific sequences like the TATA box in eukaryotes.
3. In prokaryotes, promoters often contain -10 and -35 consensus sequences recognized by sigma factors.
4. Promoter strength determines the frequency of transcription initiation.
5. Mutations in promoter regions can significantly affect gene expression levels.

Review Questions

Related terms

RNA Polymerase:

An enzyme that binds to promoters and synthesizes RNA from a DNA template.

Operon:

A cluster of genes under the control of a single promoter, transcribed as a unit.

Sigma Factor: A protein needed for initiation of transcription in prokaryotes, facilitating RNA polymerase binding to promoters.