gene regulatory element promoter In genetics, a promoter is a region of DNA that initiates transcription of a particular gene. Promoters are located near the genes they transcribe, on the same strand and upstream on the DNA (towards the 3' region of the anti-sense strand, also called template strand and non-coding strand). Promoters can be about 100–1000 base pairs long. (http://en.wikipedia.org/wiki/Promoter_(genetics)) a combination of short sequence elements, normally just upstream of a gene, to which RNA polymerase binds in order to initiate transcription of the gene.