Phosphatidylserine vesicles enable efficient en bloc transmission of enteroviruses

Chen et al., 2015, Cell 160, 619–630

Speaker: Yu-Lun Chen (陳昱倫)                                          Time: 13:00~14:00, Oct. 21, 2015

Commentator: Dr. Guey-Chuen Perng (彭貴春老師)          Place: Room 601

Abstract:

        Enteroviruses are a genus of positive-sense single-stranded RNA, non-enveloped viruses, which include polioviruses (PV), coxsackie A and B viruses (CA, CB) and human rhinovirus. The cell-to-cell spread of nonenveloped viruses usually requires cell lysis. However, there are reports that extracellular coxsackie viruses B3 (CVB3) are present in vesicles (Robinson et al., 2014) and poliovirus (PV) are able to spread non-lytically among the host cells (Bird, Maynard, Covert, & Kirkegaard, 2014). These findings raised the important questions regarding the extracellular nature of enteroviral particles and the significance of non-lytic release of the virus particles. In this study, the authors investigated the assembly, release and subsequent infection processes of enteroviral particles. Their findings showed that multiple infectious enteroviral particles were clustered within individual phosphatidylserine (PS) lipid-enriched vesicles and non-lytically secreted out of cells. These viral particles in the vesicles are more efficient in establishing infection than free viral particles. They also demonstrated that the vesicles encapsulate and traffic large numbers of mature infectious viral particles between cells and enable the transfer of multiple viral RNA genomes collectively into the new host cells by a mechanism that is dependent on both the virus-specific receptor of the recipient host cell as well as the vesicular PS lipids. This study reveals a novel mode of viral transmission, where enteroviral genomes are transmitted from cell-to-cell en bloc in membrane-bound PS vesicles instead of as single independent genomes.

References:

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