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Updated: Oct 6, 2025
09:59
Investigation of RNA Synthesis Using 5-Bromouridine Labelling and Immunoprecipitation
Published on: May 3, 2018
9.7K
Pseudouridine synthases modify human pre-mRNA co-transcriptionally and affect pre-mRNA processing
Nicole M Martinez1, Amanda Su1, Margaret C Burns2
1Yale School of Medicine, Department of Molecular Biophysics & Biochemistry, New Haven, CT 06520, USA.
Molecular Cell
|January 20, 2022
Summary
This study reveals that pseudouridine modification occurs early in mRNA's life, directly impacting gene expression by influencing splicing and processing. This cotranscriptional modification offers a new layer of gene regulation.
Area of Science:
- Molecular Biology
- RNA Biology
- Epigenetics
Background:
- Pseudouridine is a prevalent mRNA modification in humans.
- Its dynamic regulation suggests a role in gene expression control.
- Understanding when pseudouridylation occurs is key to its function.
Purpose of the Study:
- To investigate the timing of mRNA pseudouridylation during its lifecycle.
- To elucidate the regulatory roles of endogenous mRNA pseudouridylation.
- To explore the impact of pseudouridylation on pre-mRNA processing.
Main Methods:
- Single-nucleotide resolution pseudouridine profiling of chromatin-associated RNA.
- In vitro splicing assays.
- Validation of pseudouridine synthase targets on pre-mRNA.
Main Results:
- Pseudouridines were identified in nascent pre-mRNA, near splice sites, and at RNA-binding protein sites.
- Individual pseudouridines directly affect splicing efficiency.
- PUS1, PUS7, and RPUSD4 were shown to control alternative splicing and 3' end processing.
Conclusions:
- Pseudouridylation occurs cotranscriptionally on pre-mRNA.
- Cotranscriptional pseudouridylation regulates human gene expression through alternative pre-mRNA processing.
- This modification provides a novel mechanism for gene expression regulation.
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