Related Experiment Video
Updated: Jun 23, 2025
09:33
Methods to Classify Cytoplasmic Foci as Mammalian Stress Granules
Published on: May 12, 2017
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Pifithrin-µ Induces Stress Granule Formation, Regulates Cell Survival, and Rewires Cellular Signaling
Hicham Mahboubi1, Henry Yu1, Michael Malca1
1Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada.
Cells
|June 19, 2024
Summary
Pifithrin-µ induces stress granules (SGs) and alters cell signaling, impacting cell viability. This compound
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Stress granules (SGs) are dynamic cytoplasmic foci crucial in cellular stress responses.
- SG assembly is regulated by signaling pathways implicated in human diseases.
- Pifithrin-µ, an HSP70 inhibitor, is investigated for its anti-tumor potential.
Purpose of the Study:
- To investigate the effects of Pifithrin-µ on stress granule formation and cellular signaling.
- To determine the role of Pifithrin-µ in cellular homeostasis and viability.
Main Methods:
- HeLa cells were used for cell-based assays to assess viability.
- Quantitative Western blotting analyzed signaling proteins and SG components.
- Confocal microscopy and image analysis quantified SG parameters.
Main Results:
- Pifithrin-µ induced bona fide SGs without exogenous stress, with dynamic properties dependent on treatment duration.
- Phosphorylation of eIF2α was essential for Pifithrin-µ-induced SG formation.
- Pifithrin-µ modulated cell signaling, decreasing AMPK activation and increasing Akt activation, leading to reduced cell viability with prolonged exposure.
Conclusions:
- Pifithrin-µ triggers stress responses and alters cellular homeostasis.
- Understanding these effects is crucial for the therapeutic application of Pifithrin-µ and related agents.
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