What is the reason behind the weak binding efficiency of the 𝜎 − subunit of the RNA polymerase in RNA synthesis?

Question

Please choose the answer from the following choices:

A. A weak binding efficiency has importance in the dissociation of the polymerase into recyclable components for further transcription

B. A weak binding efficiency is important in order to monitor the growing mRNA from time to time if its free from errors

C. A weak binding efficiency of the 𝜎 − subunit is important in the chain termination process during transcription

D. None of the aforementioned choices is correct

Note: Please provide an explanation if you can.

Answer 1

The sigma subunit of RNA polymerase allows it to bind to a specific promoter sequence. It is important for initiation of transcription. Then it has to be released so elongation happens. I think option A is correct, as sigma subunit is usable for other transcription initiation.

C is definitely incorrect because termination is the ending step. B does not make any sense.

Ramona