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Updated: Jun 1, 2026
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Conjugative Mating Assays for Sequence-specific Analysis of Transfer Proteins Involved in Bacterial Conjugation
Published on: January 4, 2017
Convergent transcription confers a bistable switch in Enterococcus faecalis conjugation
Anushree Chatterjee1, Christopher M Johnson, Che-Chi Shu
1Department of Chemical Engineering, University of Minnesota, Minneapolis, MN 55455, USA.
Summary
Convergent transcription in Enterococcus faecalis uses RNA polymerase collisions and antisense RNA to create a robust genetic switch, controlling antibiotic resistance plasmid transfer. This mechanism highlights a novel gene regulation strategy.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Convergent gene pairs are common in genomes and thought to regulate gene expression.
- The prgX/prgQ operon in Enterococcus faecalis controls the transfer of the pCF10 antibiotic resistance plasmid.
Purpose of the Study:
- To investigate a unique gene regulation mechanism involving convergent transcription in the prgX/prgQ operon.
- To elucidate how convergent transcription controls conjugative transfer of the pCF10 plasmid.
Main Methods:
- Mathematical modeling to simulate gene regulation dynamics.
- Experimental validation of predicted regulatory mechanisms.
- Analysis of RNA transcripts resulting from convergent transcription.
Main Results:
- Convergent transcription in the prgX/prgQ operon leads to RNA polymerase (RNAP) collisions.
- RNAP collisions cause premature termination of transcripts.
- Antisense regulation occurs between complementary counter-transcripts.
- Truncated RNAs resulting from collisions engage in sense-antisense interactions.
- Both RNAP collision and antisense regulation are crucial for a robust bistable switch controlling conjugation.
Conclusions:
- Convergent transcription coupled with RNAP collision and antisense interaction forms a robust genetic switch.
- This mechanism provides a novel mode of gene regulation for plasmid transfer.
- The conserved nature of convergent transcription suggests broad applicability of this regulatory strategy across species.
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