Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end. Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3
Firstly , flanking the open reading frame , all genes contain a regulatory sequence that is required for their expression . In order to be expressed , genes require a promoter sequence . The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 A gene can have more than one promoter , resulting in messenger RNAs ( mRNA ) that differ in how far they extend in the 5 ' end . Promoter regions have a consensus sequence , however highly transcribed genes have " strong " promoter sequences that bind the transcription machinery well , whereas others have " weak " promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3
How is a promoter sequence recognized?
How is a promoter sequence recognized ?
by transcription factors and RNA polymerase
by transcription factors and RNA polymerase