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Virus entry by macropinocytosis

Jason Mercer1, Ari Helenius

  • 1ETH Zurich, Institute of Biochemistry, Schafmattsrasse 18, ETH Hoenggerberg, Zurich 8093, Switzerland.

Nature Cell Biology
|May 1, 2009
PubMed

Insights

Viruses hijack host cell macropinocytosis for entry. This process involves virus particles triggering cell signaling pathways to form large vacuoles for internalization into the cytoplasm.

Area of Science:

  • Virology
  • Cell Biology
  • Molecular Biology

Background:

  • Viruses are obligate intracellular parasites requiring host cell machinery for replication.
  • Viral entry into host cells often utilizes host cell endocytic pathways.
  • Macropinocytosis, a cellular process for fluid uptake, is exploited by various viruses.

Purpose of the Study:

  • To review the molecular mechanisms of macropinocytosis.
  • To describe the role of macropinocytosis in viral entry into host cells.

Main Methods:

  • Literature review of scientific articles on macropinocytosis and viral entry.
  • Analysis of signaling pathways and cellular machinery involved in macropinocytosis.
  • Examination of virus families known to utilize macropinocytosis.

Main Results:

  • Viruses activate host cell signaling pathways to induce actin-mediated membrane ruffling and blebbing.
  • Virus particles are internalized via large vacuoles (macropinosomes) formed at the plasma membrane.
  • Viral capsids or particles penetrate the cytosol through the macropinosome membrane.

Conclusions:

  • Macropinocytosis is a significant route for viral entry into vertebrate and insect cells.
  • Understanding macropinocytosis provides insights into viral pathogenesis and potential therapeutic targets.

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