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Publication Abstract from PubMed

Rho is a ring-shaped hexameric ATP-dependent molecular motor. Together with the transcription elongation factor NusG, Rho mediates factor-dependent transcription termination and transcription-translation-coupling quality control in Escherichia coli(1-4). Here we report the preparation of complexes that are functional in factor-dependent transcription termination from Rho, NusG, RNA polymerase (RNAP), and synthetic nucleic acid scaffolds, and we report cryogenic electron microscopy structures of the 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 nucleotides of RNA interacting sequence-specifically with the exterior of Rho and 6 nucleotides of RNA interacting sequence-specifically with the central channel of Rho; have Rho oriented relative to RNAP such that ATP-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's function.

Structural basis of Rho-dependent transcription termination.,Molodtsov V, Wang C, Firlar E, Kaelber JT, Ebright RH Nature. 2023 Feb;614(7947):367-374. doi: 10.1038/s41586-022-05658-1. Epub 2023 , Jan 25. PMID:36697824^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.