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Endosomes, exosomes and Trojan viruses

Annegret Pelchen-Matthews1, Graça Raposo, Mark Marsh

  • 1Cell Biology Unit, MRC Laboratory for Molecular Cell Biology and Department of Biochemistry and Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK. a.pelchen-matthews@ucl.ac.uk

Trends in Microbiology
|June 30, 2004
PubMed

Insights

Retroviruses, enveloped viruses, may bud from internal cell compartments, not just the plasma membrane. This suggests viral exosomes, utilizing endocytic pathways for assembly and release.

Area of Science:

  • Virology
  • Cell Biology
  • Molecular Biology

Background:

  • Retroviruses are typically thought to bud from the plasma membrane.
  • Emerging evidence suggests alternative viral assembly and release mechanisms.

Purpose of the Study:

  • To discuss the concept of retroviruses as "viral exosomes".
  • To review evidence for the endocytic pathway's role in viral biogenesis.

Main Methods:

  • Literature review and conceptual discussion.

Main Results:

  • Some enveloped viruses, including retroviruses, utilize the endocytic pathway for assembly and release.
  • Viruses exploit multivesicular body (MVB) biogenesis machinery.

Conclusions:

  • Retroviruses may be considered "viral exosomes".
  • Endocytic pathway compartments are crucial for MVB and viral particle formation.

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