Question

How does rho-independent termination work in transcription?

a) It requires a specific RNA polymerase.

b) It involves the formation of a hairpin structure in the mRNA.

c) It is dependent on a termination factor.

d) It occurs only in eukaryotic cells.

Answer 1

Rho-independent termination of transcription in prokaryotes involves the formation of a hairpin loop within the mRNA, causing RNA polymerase to stall and eventually dissociate from the DNA template.

Step-by-step explanation:

Rho-Independent Termination of Transcription

Rho-independent termination is a mechanism of ending transcription in prokaryotic cells that does not require the rho protein. Instead, it is characterized by the formation of a hairpin loop structure within the nascent mRNA molecule. When RNA polymerase transcribes a DNA sequence rich in C-G nucleotides near the end of a gene, the newly synthesized RNA can fold back onto itself, forming a hairpin due to the complementary base pairing of C-G nucleotides. This structure stalls the polymerase when it reaches a region rich in A-T nucleotides, where the mRNA transcript and the DNA template bind weakly. The result is the dissociation of the RNA polymerase from the DNA template and the release of the newly formed mRNA transcript.