Final answer:
The stem-loop structure and helicase requirement point to rho-dependent termination of transcription in bacteria, where the rho protein unwinds the RNA-DNA hybrid after RNA polymerase stalls.
Step-by-step explanation:
The formation of a stem-loop structure and the requirement for a helicase are characteristic of bacterial genes that undergo rho-dependent termination of transcription. In rho-dependent termination, the rho protein, working as a helicase, tracks along the growing mRNA chain.
Once the bacterial RNA polymerase transcribes a specific region, it encounters a sequence with a repetition of G nucleotides on the DNA template and stalls, leading the rho protein to collide with the polymerase and release the mRNA from the transcription bubble by unwinding the RNA-DNA hybrid. This is different from rho-independent termination, where the polymerase stops due to a stable hairpin loop structure formed within the mRNA itself.