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08:23
De novo Identification of Actively Translated Open Reading Frames with Ribosome Profiling Data
Published on: February 18, 2022
Translational control of Nrf2 within the open reading frame
Oscar Perez-Leal1, Carlos A Barrero, Salim Merali
1Department of Biochemistry and Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, PA, USA. operez@temple.edu
Biochemical and Biophysical Research Communications
|June 29, 2013
Summary
Scientists discovered a new mechanism that represses Nuclear Factor Erythroid 2-Related Factor 2 (Nrf2) translation. This finding explains low Nrf2 levels in cells under normal conditions, adding a new layer to gene regulation.
Area of Science:
- Molecular Biology
- Gene Regulation
- Cellular Stress Response
Background:
- Nuclear Factor Erythroid 2-Related Factor 2 (Nrf2) is crucial for antioxidant and detoxification pathways.
- Nrf2 activity is regulated at multiple levels, including transcription, translation, and post-translational modification.
- Translational control of Nrf2 synthesis is vital under stress but remains poorly understood.
Purpose of the Study:
- To identify novel molecular mechanisms regulating Nrf2 translation.
- To elucidate the process repressing Nrf2 synthesis under basal conditions.
Main Methods:
- Investigated translational control mechanisms of Nrf2.
- Analyzed the Nrf2 open reading frame (ORF) mRNA sequence.
- Utilized synonymous codon substitutions to test translational repression reversal.
Main Results:
- Identified a novel mechanism that represses Nrf2 translation under basal conditions.
- This repression is dependent on the mRNA sequence within the 3' portion of the Nrf2 ORF.
- Synonymous codon substitutions reversed the Nrf2 translational repression.
Conclusions:
- A new layer of translational control for Nrf2 has been discovered.
- This mechanism explains the low Nrf2 concentration observed in quiescent states.
- Findings provide insights into the regulation of cellular antioxidant defense.
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