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Updated: May 26, 2026
10:59
Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events
Published on: May 13, 2019
The ω subunit stabilizes transcribing RNA polymerase to balance processivity and collision resolution.
Barbare Khitiri1, Bing Wang1,2, Matthew B Cooke3
1Department of Microbiology, The Ohio State University, Columbus, OH 43210, United States.
Biorxiv : the Preprint Server for Biology
|May 25, 2026
Summary
The ubiquitous RNA polymerase (RNAP) subunit omega (ω) is not essential for stress responses. Losing ω aids RNAP release, preventing genome-damaging collisions during transcription-replication conflicts.
Area of Science:
- Molecular Biology
- Genetics
- Microbiology
Background:
- The ubiquitous RNA polymerase (RNAP) subunit omega (ω/RPB6) is traditionally considered an assembly chaperone.
- Its role in modulating bacterial sigma factor competition is also established.
Purpose of the Study:
- This study redefines the function of the Escherichia coli ω subunit, encoded by the rpoZ gene.
- Investigate the role of ω in cellular processes beyond its known functions.
Main Methods:
- CRISPR interference (CRISPRi) screening was employed to identify genetic interactions.
- Phenotypic analysis of ΔrpoZ strains under various stress conditions and genetic backgrounds (dksA, rho, seqA mutants).
- Assays measuring RNAP termination, processivity, and survival against DNA-damaging agents.
Main Results:
- ΔrpoZ strains showed no significant defects in σS-dependent stress responses.
- Loss of ω (ΔrpoZ) promoted survival during transcription-replication conflicts.
- ω deficiency sensitized RNAP to termination, reduced RNAP processivity, and suppressed toxic effects of DNA-damaging agents in specific genetic backgrounds.
Conclusions:
- Loss of ω facilitates the removal of stalled RNAP, preventing catastrophic replisome collisions.
- ω/RPB6 homologs may play a conserved role in balancing RNAP processivity and controlled release to maintain genome integrity.
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