Question

Identify the correct statement.

• A. Split gene arrangement is characteristic of prokaryotes
• B. In capping, methyl guanosine triphosphate is added to the 39 end of hnRNA.
• C. RNA polymerase binds with Rho factor to terminate the process of transcription in bacteria
• D. The coding strand in a transcription unit is copied to an mRNA

Answer 1

The Correct Option is C

In bacterial transcription, termination occurs in two main ways, and the Rho factor is involved in one of them:
Rho-independent termination: In this mechanism, a specific sequence in the DNA template strand causes the newly synthesized RNA transcript to form a hairpin structure, followed by a run of uracil (U) residues. This hairpin structure disrupts the RNA polymerase's interaction with the DNA template, causing the polymerase to pause and ultimately dissociate from the DNA, resulting in transcription termination.
Rho-dependent termination: Rho factor is a protein that can assist in transcription termination in bacteria. Rho binds to the newly synthesized RNA transcript and moves along it in the 5' to 3' direction, tracking the RNA polymerase. When the RNA polymerase encounters a Rho utilization (rut) site, a region rich in cytosine (C) residues, it pauses. Rho then catches up and uses its helicase activity to unwind the RNA-DNA hybrid, releasing the RNA transcript and terminating transcription.

So, statement (C) accurately describes the role of the Rho factor in transcription termination in bacteria.