AI Article Synopsis
- RNA polymerase (RNAP) pauses during DNA transcription to help regulate gene expression, with the transcription factors NusA and NusG influencing this pausing in opposing ways.
- Cryo-EM studies of Escherichia coli RNAP show how NusA promotes RNAP's swivelling, leading to more pausing, while NusG reduces this effect.
- The findings suggest that NusA and NusG work together during transcription termination, providing insights into the randomness of pausing and how these factors modulate the process.
Article Abstract
RNA polymerase (RNAP) frequently pauses during the transcription of DNA to RNA to regulate gene expression. Transcription factors NusA and NusG modulate pausing, have opposing roles, but can bind RNAP simultaneously. Here we report cryo-EM reconstructions of Escherichia coli RNAP bound to NusG, or NusA, or both. RNAP conformational changes, referred to as swivelling, correlate with transcriptional pausing. NusA facilitates RNAP swivelling to further increase pausing, while NusG counteracts this role. Their structural effects are consistent with biochemical results on two categories of transcriptional pauses. In addition, the structures suggest a cooperative mechanism of NusA and NusG during Rho-mediated transcription termination. Our results provide a structural rationale for the stochastic nature of pausing and termination and how NusA and NusG can modulate it.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8940904 | PMC |
| http://dx.doi.org/10.1038/s41467-022-29148-0 | DOI Listing |
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