Question

You design a reconstructive RNA polymerase where you take the beta and alpha subunit from a rifampicin resistant strain and beta prime and sigma subunit from rifampicin sensitive strain. You check the rate of transcription by this RNA polymerase after the addition of the antibiotic. What will be your observation?

(a) No transcription

(b) Reduced transcription

(c) Normal transcription

(d) Improved transcription

The question was posed to me in final exam.

I need to ask this question from Transcription in Prokaryotes : Elongation topic in section Gene Expression : Transcription Prokaryotes of Cytogenetics

Answer 1

Correct choice is (c) Normal transcription

For explanation: The beta subunit of the RNA polymerase is mainly sensitive to Rifampicin. Thus the re-constructed RNA pol is overall Rifampicin resistant and transcription rate will be normal.