How Does a Positive Regulator Affect Transcription by RNA Polymerase

Question

How does a positive regulator affect transcription by RNA polymerase in prokaryotes?
A)by allowing passage of the polymerase through an operator
B)by interacting with RNA polymerase to increase the frequency of transcription initiation
C)by causing the helix to unwind in the operator allowing easier initiation
D)by making the transcription start site more exposed to the polymerase

Accepted Answer

Positive regulators (activators) in prokaryotes often function by directly interacting with RNA polymerase, thereby increasing the frequency of transcription initiation. This interaction can help stabilize the binding of RNA polymerase to the promoter or enhance its ability to begin transcription.