Journal
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Volume 118, Issue 16, Pages -Publisher
NATL ACAD SCIENCES
DOI: 10.1073/pnas.2023426118
Keywords
transcription-translation coupling; nascent mRNA; translational riboswitch; RNA polymerase; ribosome
Categories
Funding
- NIH [GM062357, GM118524, GM131922, R01 GM067153]
Ask authors/readers for more resources
In bacteria, the interaction between RNA polymerase and ribosome regulates gene expression through transcription-translation coupling. This coupling is mainly achieved by RNA polymerase promoting the binding of the ribosomal 30S subunit to antagonize ribosome binding site occlusion induced by a riboswitch, thereby facilitating translation.
Bacterial messenger RNA (mRNA) synthesis by RNA polymerase (RNAP) and first-round translation by the ribosome are often coupled to regulate gene expression, yet how coupling is established and maintained is ill understood. Here, we develop biochemical and single-molecule fluorescence approaches to probe the dynamics of RNAP-ribosome interactions on an mRNA with a translational preQ(1)-sensing riboswitch in its 5' untranslated region. Binding of preQ(1) leads to the occlusion of the ribosome binding site (RBS), inhibiting translation initiation. We demonstrate that RNAP poised within the mRNA leader region promotes ribosomal 30S subunit binding, antagonizing preQ(1)-induced RBS occlusion, and that the RNAP-30S bridging transcription factors NusG and RfaH distinctly enhance 30S recruitment and retention, respectively. We further find that, while 30S-mRNA interaction significantly impedes RNAP in the absence of translation, an actively translating ribosome promotes productive transcription. A model emerges wherein mRNA structure and transcription factors coordinate to dynamically modulate the efficiency of transcription-translation coupling.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available