Related Experiment Video

Updated: May 24, 2025

Assessment of Selective mRNA Translation in Mammalian Cells by Polysome Profiling
10:00

Assessment of Selective mRNA Translation in Mammalian Cells by Polysome Profiling

Published on: October 28, 2014

28.1K

ProQ prevents mRNA degradation through inhibition of poly(A) polymerase

Sofia Bergman1, Christopher Birk, Erik Holmqvist1

  • 1Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, 75124 Uppsala, Sweden.

Nucleic Acids Research
|March 4, 2025
PubMed

Insights

The bacterial RNA-binding protein ProQ enhances biofilm formation by stabilizing messenger RNA (mRNA) through inhibiting polyadenylation. This mechanism is crucial for bacterial virulence and survival.

Area of Science:

  • Bacteriology
  • Molecular Biology
  • Genetics

Background:

  • The RNA-binding protein ProQ influences bacterial mRNA levels, impacting virulence traits like motility and survival.
  • The precise mechanism by which ProQ increases mRNA levels and affects these phenotypes remains unclear.

Purpose of the Study:

  • To elucidate the mechanism by which ProQ regulates mRNA levels and its role in bacterial virulence.
  • To investigate ProQ's impact on biofilm formation and its relationship with sigma factor RpoS.

Main Methods:

  • Investigated ProQ's effect on biofilm formation in Salmonella Typhimurium.
  • Analyzed ProQ's impact on RpoS protein and mRNA levels.
  • Examined the role of poly(A) polymerase I (PAPI) in ProQ-mediated RNA regulation.
  • Assessed the effect of purified ProQ on PAPI activity in vitro.

Main Results:

  • ProQ promotes biofilm formation, dependent on the sigma factor RpoS.
  • ProQ increases RpoS protein and mRNA levels without affecting transcription or translation.
  • ProQ protects rpoS mRNA from 3' end-dependent decay mediated by PAPI.
  • Purified ProQ inhibits PAPI-mediated polyadenylation.
  • PAPI is essential for ProQ's influence on genes related to biofilm, motility, and virulence.

Conclusions:

  • ProQ functions as a general inhibitor of polyadenylation, protecting bacterial transcripts from decay.
  • This inhibition of polyadenylation by ProQ is a key mechanism regulating gene expression and bacterial virulence traits.

More Related Videos

High-throughput Screening for Chemical Modulators of Post-transcriptionally Regulated Genes09:44

High-throughput Screening for Chemical Modulators of Post-transcriptionally Regulated Genes

Published on: March 3, 2015

9.4K
Investigation of RNA Synthesis Using 5-Bromouridine Labelling and Immunoprecipitation09:59

Investigation of RNA Synthesis Using 5-Bromouridine Labelling and Immunoprecipitation

Published on: May 3, 2018

9.5K

Related Concept Videos

mRNA Stability and Gene Expression02:51

mRNA Stability and Gene Expression

The structure and stability of mRNA molecules regulates gene expression, as mRNAs are a key step in the pathway from gene to protein. In eukaryotes, the half-life of mRNA varies from a few minutes up to several days. mRNA stability is essential in growth and development. The absence of the proteins regulating its stability, such as tristetraprolin in mice, can cause systemic issues, including bone marrow overgrowth, inflammation, and autoimmunity.
Cis-acting Elements involved in mRNA stability
5.5K
pre-mRNA Processing02:01

pre-mRNA Processing

In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl...
52.5K
Nonsense-mediated mRNA Decay02:27

Nonsense-mediated mRNA Decay

The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
10.4K
Pre-mRNA Processing: Modification of pre-mRNA Ends01:35

Pre-mRNA Processing: Modification of pre-mRNA Ends

In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a cap to the 5' end of the growing transcript. In this process, a 5' phosphate is replaced by modified guanosine that has a methyl group attached (7-methyl guanosine). This 5' cap helps...
9.1K
Nuclear Export of mRNA02:31

Nuclear Export of mRNA

Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
7.5K
Regulation of Expression at Multiple Steps01:23

Regulation of Expression at Multiple Steps

The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the...
863