In the following prokaryotic DNA sequence, label the highlighted regions. Using the prokaryotic DNA sequence above, describe the relationship between the highlighted regions and how mutations in each region may affect gene expression

Question

What will be an ideal response?

Answer 1

The -10 (Pribnow) and -35 consensus sequences are important because of their nucleotide content, their location relative to one another, and their location relative to the start of transcription. Mutation in a consensus sequence is likely to alter how efficiently a protein binds to the promoter, and to decrease the amount of gene transcription. In contrast, mutations between consensus sequences are unlikely to alter gene transcription, because the sequences in these intervening regions do not bind tightly to RNA polymerase. The nucleotides between -10 and -35 are important as spacers between the consensus elements, but their specific sequences are not critical.