How does a core promoter differ from a promoter?

How does a core promoter differ from a promoter?

• A. The promoter is a minimal sequence for initiation; the core promoter includes enhancers.
• B. The core promoter includes enhancers.
• C. The core promoter is the minimal sequence for initiation; a promoter includes additional proximal/distal regulatory elements.
• D. The core promoter regulates translation; the promoter regulates transcription.

Answer: (C)

The key idea is that transcription initiation relies on a core promoter that provides the minimal set of DNA elements necessary for RNA polymerase II and general transcription factors to start transcription. The core promoter sits at the transcription start site and includes elements like the TATA box or initiator that position the polymerase for basal initiation. A promoter, in contrast, covers a broader region that includes this core but also adds proximal regulatory elements near the start site and distal regulatory elements further away. These additional elements bind gene-specific transcription factors and, often through DNA looping, modulate how much, when, and in which tissues transcription occurs. So the core promoter defines the basic start of transcription, while the promoter region as a whole integrates regulatory inputs to tune expression.

The key idea is that transcription initiation relies on a core promoter that provides the minimal set of DNA elements necessary for RNA polymerase II and general transcription factors to start transcription. The core promoter sits at the transcription start site and includes elements like the TATA box or initiator that position the polymerase for basal initiation. A promoter, in contrast, covers a broader region that includes this core but also adds proximal regulatory elements near the start site and distal regulatory elements further away. These additional elements bind gene-specific transcription factors and, often through DNA looping, modulate how much, when, and in which tissues transcription occurs. So the core promoter defines the basic start of transcription, while the promoter region as a whole integrates regulatory inputs to tune expression.