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Methods to Classify Cytoplasmic Foci as Mammalian Stress Granules
Published on: May 12, 2017
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Stress granules regulate paraspeckles: RNP granule continuum at work
Haiyan An1, Tatyana A Shelkovnikova1
1Medicines Discovery Institute, Cardiff University, Cardiff, CF10 3AT, United Kingdom.
Cell Stress
|December 14, 2019
Summary
Nuclear and cytoplasmic ribonucleoprotein (RNP) granules are connected, forming a cellular continuum. This connection is crucial for regulating cellular stress responses and managing phase separation within cells.
Area of Science:
- Cell Biology
- Biochemistry
- Molecular Biology
Background:
- Eukaryotic cells contain ribonucleoprotein (RNP) granules, which are membraneless structures formed by liquid-liquid phase separation.
- These RNP granules function as biochemical microreactors and environmental sensors within cells.
- The connections between spatially distinct RNP granules are not well understood.
Purpose of the Study:
- To investigate the relationship between nuclear paraspeckles and cytoplasmic stress granules (SGs).
- To determine if SGs regulate stress-induced paraspeckle assembly.
- To explore the concept of an intracellular "RNP granule continuum".
Main Methods:
- Affinity purification of paraspeckles.
- Analysis of paraspeckle and SG interactions under cellular stress conditions.
Main Results:
- Cytoplasmic stress granules (SGs) were identified as key regulators of stress-induced paraspeckle assembly.
- Despite residing in different cellular compartments, paraspeckles and SGs are closely interconnected.
- The study supports the existence of an "RNP granule continuum" involving nuclear and cytoplasmic granules.
Conclusions:
- Nuclear and cytoplasmic RNP granules form an integrated continuum, facilitating rapid component exchange.
- This exchange is vital for the temporal control of cellular stress responses.
- Cells exhibit tolerance for phase separation, evidenced by "bursts" of RNP granule formation, suggesting potential therapeutic targets for diseases involving RNP granule dysfunction.
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