Visualizing infection of individual influenza viruses

Speaker : 姚 奕 全

Commentator : 陳 舜 華 老師

Date : 2003/10/15  15:00~16:00

Place : Room 601

Abstract：

    Influenza virus is a well-manipulated model system for studying viral infection. Influenza virus infects cell through receptor-mediated endocytosis, then moves from early endosomes to late endosomes, finally fuses with the endosomal membrane and releases viral genes. The authors use real-time fluorescence microscopy to track 1,1'-dioctadecyl- 3,3,3',3'-tetramethylindodicarbocyanine (DiD) -labeled virus in the Chinese hamster ovary (CHO) cells. They discovered that virus-containing endosomes were transported in three separate stages. Viruses first started an actin-dependent movement in the cell periphery, and then rapidly translocated to the perinuclear region with a dynein-directed pathway and finally moved intermittently close to the nucleus before fusion. Interestingly, they found that virus-bearing endosomes initiated endocytic acidification which was largely occurred in the perinuclear region, but not in the early endosomes near the cell periphery. Addition to the previous study that acidification occurs in the early endosomes, this finding reveals a different endocytic pathway toward late endosomes, including maturation and initial acidification, mainly takes place in the perinuclear region.

References：

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3.      Lakadamyali, M., Zhuang, X., et al. Visualizing infection of individual influenza viruses. Proc. Natl. Acad. Sci. USA 87. 6579 – 6583 (2003).