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Early Viral Entry Assays for the Identification and Evaluation of Antiviral Compounds
09:29

Early Viral Entry Assays for the Identification and Evaluation of Antiviral Compounds

Published on: October 29, 2015

Early steps of polyomavirus entry into cells

J M Gilbert1, T L Benjamin

  • 1Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA. jgilbert@hms.harvard.edu

Journal of Virology
|August 23, 2000
PubMed

Insights

Murine polyomavirus enters cells via a novel pathway, independent of clathrin and caveolin-1. This discovery reveals a new mechanism for viral entry, crucial for understanding polyomavirus infection.

Area of Science:

  • Virology
  • Cell Biology
  • Molecular Biology

Background:

  • The cellular entry mechanisms of murine polyomavirus remain largely unknown.
  • Related polyomaviruses like Simian virus 40 and JC virus utilize distinct endocytic pathways (caveola- and clathrin-mediated, respectively).

Purpose of the Study:

  • To elucidate the cellular uptake mechanism of murine polyomavirus.
  • To determine if murine polyomavirus employs clathrin- or caveolin-1-mediated endocytosis for cell entry.

Main Methods:

  • Infectivity assays using compounds that inhibit endocytosis.
  • Immunofluorescence microscopy to assess colocalization with clathrin and caveolin-1.
  • Uptake studies using a dominant-negative dynamin I mutant.

Main Results:

  • Inhibitors of caveola- and clathrin-mediated endocytosis did not affect polyomavirus infectivity.
  • Murine polyomavirus did not colocalize with clathrin light chain or caveolin-1.
  • Dynamin I inhibition did not impact polyomavirus uptake or infectivity.

Conclusions:

  • Murine polyomavirus utilizes a clathrin-, caveolin-1-, and dynamin I-independent pathway for cellular entry.
  • Viral uptake occurs via a distinct class of uncoated vesicles, differing from related polyomaviruses.

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