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10:16
Detection of Viral RNA by Fluorescence in situ Hybridization (FISH)
Published on: May 5, 2012
Permeability to inhibitors of protein synthesis in virus infected cells
Molecular Biology Reports
|December 1, 1984
Abstract:
Infection of HeLa cells with different viruses induces permeabilization of the cell membrane to protein toxins such as alpha-sarcin. This phenomenon occurs with HeLa, KB, BHK-21 and L929 cells and EMC, SFV, VSV and Polio virus and is dependent on the ability of the virus to infect the cells. Inhibitors of endocytosis and lysosomotropic agents do not affect this process. Cells become sealed to the toxin approximately four hours after the infection. Sulfhydryl reagents impair cellular permeabilization to alpha-sarcin.
Insights
Viral infection makes cell membranes permeable to toxins like alpha-sarcin. This cellular permeabilization, observed in various cell lines and viruses, is reversible and sensitive to sulfhydryl reagents.
Area of Science:
- Cell Biology
- Virology
- Molecular Biology
Background:
- Cell membrane integrity is crucial for cellular function.
- Viral infections can alter host cell physiology.
- Selective permeability of the cell membrane restricts entry of large molecules like protein toxins.
Purpose of the Study:
- To investigate the effect of viral infection on cell membrane permeability.
- To determine the susceptibility of infected cells to protein toxins.
- To identify factors influencing virus-induced membrane permeabilization.
Main Methods:
- Infection of various cell lines (HeLa, KB, BHK-21, L929) with different viruses (EMC, SFV, VSV, Polio).
- Assessing cell membrane permeabilization using protein toxins, specifically alpha-sarcin.
- Testing the effect of endocytosis inhibitors, lysosomotropic agents, and sulfhydryl reagents.
Main Results:
- Viral infection induces cell membrane permeabilization to protein toxins like alpha-sarcin.
- This phenomenon is observed across multiple cell lines and virus types, dependent on successful viral infection.
- Permeabilization is not affected by inhibitors of endocytosis or lysosomotropic agents.
- Cells regain membrane integrity approximately four hours post-infection.
- Sulfhydryl reagents inhibit the virus-induced cellular permeabilization.
Conclusions:
- Viral infection can transiently disrupt cell membrane integrity, allowing entry of protein toxins.
- The mechanism of permeabilization is virus-dependent and distinct from endocytosis.
- Cellular sulfhydryl groups play a role in maintaining membrane integrity during viral infection.
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