Question

In an experiment you mutate the C terminal domain of alpha subunit of the RNA polymerase. What will you expect to see?

(a) Transcription is absent

(b) Transcription is at random sites

(c) Transcription is less

(d) Transcription is more

I have been asked this question in an online quiz.

Question is taken from Transcription in Prokaryotes : Initiation topic in chapter Gene Expression : Transcription Prokaryotes of Cytogenetics

Answer 1

Correct answer is (c) Transcription is less

Explanation: The C terminal domain of the alpha subunit is responsible for binding to the UP elements of the promoter. Such binding helps to enhance transcription so in absence of the binding transcription will be slower. However, still transcription will occur due to the presence of core promoter.