What are the promoter sequences?

Promoter sequences are sequences of DNA that determine where transcription of a gene will be initiated by RNA polymerase. They also indicate the sense strand (which DNA strand is to be transcribed) and define the direction of transcription. Promoter sequences are located directly upstream or at the 5' end of the transcription initiation site. Transcription is initiated when RNA polymerase and the necessary transcription factors bind to the promoter sequence. There are three promoter sequences in eukaryotic cells: 

Core Promoter – Located closest to the start codon, the core promoter region contains the RNA polymerase binding site, transcription start site, and TATA box.

Proximal Promoter – The proximal promoter contains several primary regulatory components and is the site where general transcription factors bind. It is located further upstream from the core promoter. 

Distal Promoter – Located upstream of the proximal promoter, the distal promoter mostly contains regulatory elements. It also contains transcription factor binding sites.