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bioRxiv · 10.1101/2022.08.29.505764

Structural basis of Rho-dependent transcription termination

Molodtsov, V.·Wang, C.·Firlar, E.·Kaelber, J. T.·Ebright, R. H.
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Abstract

Rho and NusG mediate factor-dependent transcription termination in Escherichia coli. Here, we report preparation of complexes functional in factor-dependent termination from RNA polymerase (RNAP), Rho, NusG, and synthetic nucleic-acid scaffolds, and we report cryo-EM structures of complexes. The structures show that functional factor-dependent pre-termination complexes contain a closed-ring Rho hexamer, have RNA threaded through the central channel of Rho, have 60 nt of RNA interacting sequence-specifically with the exterior of Rho and 6 nt of RNA interacting sequence-specifically with the central channel of Rho, have Rho oriented relative to RNAP such that ATP-hydrolysis-dependent translocation by Rho exerts mechanical force on RNAP, and have NusG bridging Rho and RNAP. The results explain five decades of research on Rho and provide a foundation for understanding Rho function. One sentence summaryCryo-EM reveals the structure of the functional Rho pre-termination complex

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Molodtsov, V., Wang, C., Firlar, E., Kaelber, J. T., Ebright, R. H.. 2022-08-29. Structural basis of Rho-dependent transcription termination. https://doi.org/10.1101/2022.08.29.505764

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