You have identified a mutation in a gene that also seems to decrease transcription of another gene 2000 bp away from the mutation site. What regulatory sequence, which may be found within another gene, has likely been mutated in this instance?
A)core promoter
B)proximal elements
C)enhancer sequence
D)homeodomain motif
E)upstream activator sequence

Question

Quizplus · Accepted Answer

The regulatory sequence that can affect transcription of a gene 2000 bp away is most likely an enhancer sequence, which can act over long distances to enhance transcription of nearby genes. Mutations in enhancer sequences can decrease transcription of the target gene. Core promoters and proximal elements are important for transcription initiation of the nearby gene, but are unlikely to affect transcription of a gene located 2000 bp away. Homeodomain motifs are DNA binding domains found in transcription factors and do not directly regulate transcription. Upstream activator sequences are cis-regulatory elements that activate transcription and are typically found within the promoter region of the target gene, rather than in another gene.

You Have Identified a Mutation in a Gene That Also