8AC1

RNA polymerase at U-rich pause bound to non-regulatory RNA - inactive, open clamp state

Summary for 8AC1

• Entry DOI: 10.2210/pdb8ac1/pdb
• EMDB information: 15330
• Descriptor: DNA-directed RNA polymerase subunit alpha, DNA-directed RNA polymerase subunit beta, DNA-directed RNA polymerase subunit beta', ... (9 entities in total)
• Functional Keywords: rna polymerase, transcriptional pausing, transcription termination, regulatory rna, transcription
• Biological source: Escherichia coli K-12; More
• Total number of polymer chains: 8
• Total formula weight: 611002.18

Authors

Dey, S.,Weixlbaumer, A. (deposition date: 2022-07-05, release date: 2022-10-26, Last modification date: 2024-07-24)

Primary citation

Dey, S.,Batisse, C.,Shukla, J.,Webster, M.W.,Takacs, M.,Saint-Andre, C.,Weixlbaumer, A.
Structural insights into RNA-mediated transcription regulation in bacteria.
Mol.Cell, 82:3885-, 2022

PubMed Abstract: RNA can regulate its own synthesis without auxiliary proteins. For example, U-rich RNA sequences signal RNA polymerase (RNAP) to pause transcription and are required for transcript release at intrinsic terminators in all kingdoms of life. In contrast, the regulatory RNA putL suppresses pausing and termination in cis. However, how nascent RNA modulates its own synthesis remains largely unknown. We present cryo-EM reconstructions of RNAP captured during transcription of putL variants or an unrelated sequence at a U-rich pause site. Our results suggest how putL suppresses pausing and promotes its synthesis. We demonstrate that transcribing a U-rich sequence, a ubiquitous trigger of intrinsic termination, promotes widening of the RNAP nucleic-acid-binding channel. Widening destabilizes RNAP interactions with DNA and RNA to facilitate transcript dissociation reminiscent of intrinsic transcription termination. Surprisingly, RNAP remains bound to DNA after transcript release. Our results provide the structural framework to understand RNA-mediated intrinsic transcription termination.

PubMed: 36220101
DOI: 10.1016/j.molcel.2022.09.020

Experimental method

ELECTRON MICROSCOPY (4.06 Å)