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Oropouche virus entry into HeLa cells involves clathrin and requires endosomal acidification
Rodrigo I M Santos1, Alcir H Rodrigues, Maria Lúcia Silva
1Department of Cell and Molecular Biology, University of São Paulo School of Medicine at Ribeirão Preto, Brazil. risantos@usp.br
Virus Research
|October 9, 2008
Summary
Oropouche virus (ORO) enters HeLa cells via clathrin-coated vesicles, a process inhibited by chlorpromazine and sensitive to endosomal acidification. This reveals key mechanisms of ORO viral entry and replication.
Area of Science:
- Virology
- Cell Biology
- Infectious Diseases
Background:
- Oropouche virus (ORO), a Bunyaviridae family member, is a significant cause of arboviral febrile illness in Brazil.
- Understanding the cellular entry mechanisms of ORO is crucial for developing antiviral strategies.
Purpose of the Study:
- To elucidate the specific pathway utilized by Oropouche virus for entry into host cells (HeLa).
- To investigate the role of endocytosis and endosomal acidification in the ORO viral replication cycle.
Main Methods:
- Utilized chlorpromazine to assess its impact on early ORO replication steps.
- Employed transmission electron microscopy (TEM) and immunofluorescence assays.
- Investigated the effect of endosomal acidification inhibitors on ORO entry.
Main Results:
- Chlorpromazine demonstrated inhibition of early ORO replication, suggesting a role in entry or uncoating.
- ORO was observed to enter HeLa cells through clathrin-coated vesicles.
- The entry mechanism was found to be susceptible to inhibitors of endosomal acidification.
- TEM and immunofluorescence confirmed ORO association with clathrin-coated pits and late endosomes within one hour.
Conclusions:
- Oropouche virus utilizes clathrin-mediated endocytosis for cellular entry.
- Endosomal acidification plays a critical role in the ORO viral lifecycle post-entry.
- These findings provide insights into the molecular mechanisms of ORO infection.
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