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Stability of Intracellular Protein Concentration under Extreme Osmotic Challenge
Jordan E Hollembeak1, Michael A Model1
1Department of Biological Sciences, Kent State University, Kent, OH 44023, USA.
Cells
|December 24, 2021
Summary
Cell volume regulation is complex; intracellular protein concentration remains stable long-term, even increasing under stress, suggesting cytoplasm resists dilution. Further research is needed on mTOR and VRAC involvement.
Area of Science:
- Cell biology
- Biophysics
Background:
- Cell volume regulation is crucial for cellular function.
- Short-term studies are common, but long-term effects on protein concentration are less understood.
Purpose of the Study:
- To monitor intracellular protein concentration (PC) over extended periods (up to 48 hours).
- To investigate cellular responses to varying osmolarities and identify mechanisms of protein concentration homeostasis.
Main Methods:
- Quantitative phase imaging using the transport-of-intensity equation.
- Cell volume measurements via exclusion of an external absorbing dye.
- Long-term monitoring of HeLa and 3T3 cells under diverse osmotic conditions.
Main Results:
- Intracellular protein concentration remained stable across a wide range of osmolarities (one-third to twice normal).
- Extreme hypoosmolarity and gramicidin treatment induced a dehydration response, increasing PC.
- Dilute media caused vacuole formation, with cytoplasm maintaining normal density.
Conclusions:
- Cellular dehydration is a response to severe stress.
- The cytoplasm exhibits resistance to prolonged dilution.
- The roles of mTOR and VRAC in protein concentration maintenance require further investigation.
Keywords:
cell volume regulationintracellular watermacromolecular crowdingtransmission-through-dyetransport-of-intensity equationvacuolizationMore Related Videos
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