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Simplified Reverse Genetics Method to Recover Recombinant Rotaviruses Expressing Reporter Proteins
Published on: April 17, 2020
Rotavirus assembly: an alternative model that utilizes an atypical trafficking pathway
1INSERM-UPMC UMR 538, "Membrane traffic and signalization in epithelial cells", CHU Saint-Antoine, 27 rue de Chaligny, 75012 Paris, France.
Current Topics in Microbiology and Immunology
|August 17, 2006
Summary
Rotavirus assembly in intestinal cells differs from kidney cells, occurring outside the endoplasmic reticulum (ER) with apical release. This novel pathway involves VP4 protein interactions with membrane rafts and bypasses classical exocytic routes.
Area of Science:
- Virology
- Cell Biology
- Molecular Biology
Background:
- Rotavirus assembly is traditionally studied in MA104 kidney cells, suggesting endoplasmic reticulum (ER) involvement and cell lysis for release.
- Recent findings in intestinal cells propose an alternative rotavirus assembly and release mechanism.
Purpose of the Study:
- To review recent advances in understanding rotavirus and rotaviral protein trafficking and assembly within intestinal cells.
- To highlight differences in rotavirus assembly pathways between intestinal and kidney epithelial cells.
Main Methods:
- Review of existing data on rotavirus assembly in intestinal cells.
- Analysis of protein interactions, specifically VP4 with cellular components and membrane microdomains.
- Investigation of polarized trafficking pathways in infected intestinal cells.
Main Results:
- Rotavirus assembly in intestinal cells appears to finalize outside the ER, with apical release and minimal cell lysis.
- Key viral protein VP4 interacts with cholesterol- and sphingolipid-rich membrane rafts.
- VP4 does not localize to the ER or Golgi in infected intestinal cells, suggesting an atypical trafficking route.
Conclusions:
- Rotavirus assembly in intestinal cells follows a distinct pathway compared to kidney cells.
- This pathway is raft-dependent, involves VP4 targeting to the apical membrane, and bypasses the classical exocytic route.
- Interactions with cellular proteins like Hsp70 and cytoskeletal components are crucial for this atypical polarized trafficking.
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