Promoter

In genetics, a promoter is a DNA sequence that enables a gene to be transcribed. The promoter is recognized by RNA polymerase, which then initiates transcription.

Promoter sequences

Prokaryotic promoters

In prokaryotes, the promoter consists of two short sequences at -10 and -35 position upstream of the gene, that is, prior to the gene in the direction of transctiption.

    <-- upstream                                                          downstream -->
 5'-XXXXXXXPPPPPXXXXXXPPPPPXXXXGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGXXXX-3'
            -35        -10     Gene to be transcribed

Eukaryotic promoters