Promoters and enhancers are DNA sequences that attract transcription factors to regulate gene expression.

“each gene each bit of dna in chromosomes in genomes has this code for the protein but also near it it's got another bit of dna that's called a promoter or an enhancer and this is a bit of dna that doesn't code for a protein what it does is it attracts what are called transcription factors things that decide whether that bit of dna gets turned into rna and then into protein they by changing the structure by changing things around the gene they determine whether this gene is expressed at all it could sit there quiet and not make the rna and the protein or it could be active make the rna and the protein”