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Early Viral Entry Assays for the Identification and Evaluation of Antiviral Compounds
Published on: October 29, 2015
Early steps of polyomavirus entry into cells.
1Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA. jgilbert@hms.harvard.edu
Journal of Virology
|August 23, 2000
Summary
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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