Related Experiment Video
Updated: Jun 21, 2025
06:01
Standardized Methods for Measuring Induction of the Heat Shock Response in Caenorhabditis elegans
Published on: July 3, 2020
8.8K
Cellular function of the GndA microprotein during heat shock
Jessica J Mohsen1,2, Michael G Mohsen3,4, Kevin Jiang1,2
1Department of Chemistry, Yale University, New Haven, CT 06511.
Biorxiv : the Preprint Server for Biology
|July 9, 2024
Summary
This study identifies GndA, a small protein regulating respiratory complex I in E. coli during heat shock. Its absence disrupts cell homeostasis and growth, highlighting the role of overlapping genes.
Area of Science:
- Microbiology
- Molecular Biology
- Genomics
Background:
- Small open reading frame-encoded polypeptides (SEPs) are increasingly identified, but those nested within protein-coding genes remain understudied.
- Escherichia coli harbors numerous SEPs, including those overlapping known genes in alternative reading frames.
Purpose of the Study:
- To characterize GndA, a novel heat shock-regulated SEP encoded in the +2 reading frame of the gnd gene in E. coli.
- To investigate the function of GndA in cellular response to heat shock.
Main Methods:
- Co-immunoprecipitation to identify GndA interacting proteins.
- Analysis of GndA deletion mutant (ΔGndA) phenotypes under heat shock conditions.
- Measurement of cell growth, NADH+/NAD ratio, and gene expression.
Main Results:
- GndA interacts with components of respiratory complex I (RCI).
- GndA is essential for proper RCI subunit localization during heat shock.
- ΔGndA cells exhibit impaired growth, altered NADH+/NAD ratio, and dysregulated gene expression, including oxidative stress genes.
Conclusions:
- GndA plays a role in maintaining cellular homeostasis during heat shock, likely through its interaction with RCI.
- This study supports the growing evidence for functional, overlapping genes in diverse genomes.
- GndA represents a newly characterized functional SEP with implications for understanding gene regulation and stress response.
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