Transcription and Translation Practice Test

Rho-dependent termination is driven by a hexameric helicase that binds to rut sites on the growing RNA and uses ATP hydrolysis to translocate along the transcript toward RNA polymerase. When it catches up to the paused transcription complex, Rho destabilizes the RNA–DNA–RNAP interaction and promotes release of the RNA, terminating transcription. The other descriptions refer to different termination mechanisms: intrinsic (rho-independent) termination involves a GC-rich hairpin followed by a poly-U tail, and the idea of termination just from a terminator sequence or from ribosome collisions does not capture rho’s ATP-driven chase along the RNA.