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Characterizing Cellular Proteins with In-cell Fast Photochemical Oxidation of Proteins
Published on: March 11, 2020
Enhanced protein denaturation in indomethacin-treated cells
I Roussou1, v T Nguyen, G N Pagoulatos
1Laboratory of General Biology, Medical School, University of Ioannina, Greece. eroussou@cc.uoi.gr
Cell Stress & Chaperones
|March 4, 2000
Summary
Indomethacin, an anti-inflammatory drug, enhances heat shock protein aggregation and response at lower temperatures. This suggests it accelerates denatured protein accumulation, lowering the heat shock response threshold.
Area of Science:
- Molecular Biology
- Cellular Stress Response
- Pharmacology
Background:
- Indomethacin activates heat shock transcription factor 1 (HSF1) DNA-binding activity.
- This activation alone is insufficient for elevated heat shock gene expression.
- Indomethacin pretreatment enables a complete heat shock response at otherwise insufficient temperatures.
Purpose of the Study:
- To investigate the mechanism by which indomethacin enhances heat shock response.
- To determine if indomethacin affects protein denaturation and aggregation at moderate temperatures.
Main Methods:
- Murine cells expressing nuclear or cytoplasmic luciferase were pretreated with indomethacin.
- Heat-induced loss of luciferase enzymatic activity was measured.
- Aggregation of 70-kDa heat shock protein and beta-galactosidase was assessed in the presence of indomethacin.
Main Results:
- Indomethacin pretreatment enhanced the heat-induced loss of luciferase activity.
- Indomethacin increased the aggregation of 70-kDa heat shock protein.
- Indomethacin also increased the aggregation of beta-galactosidase.
Conclusions:
- Indomethacin accelerates the accumulation of denatured proteins within cells at moderate temperatures.
- This acceleration lowers the temperature threshold required to elicit a heat shock response.
- Indomethacin's effect on protein denaturation is a key factor in modulating cellular stress responses.
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