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Viral Generated Inter-Organelle Contacts Redirect Lipid Flux for Genome Replication.

ABSTRACT: Positive-stranded RNA viruses extensively remodel host cell architecture to enable viral replication. Here, we examined the poorly understood formation of specialized membrane compartments that are critical sites for the synthesis of the viral genome. We show that the replication compartments (RCs) of enteroviruses are created through novel membrane contact sites that recruit host lipid droplets (LDs) to the RCs. Viral proteins tether the RCs to the LDs and interact with the host lipolysis machinery to enable transfer of fatty acids from LDs, thereby providing lipids essential for RC biogenesis. Inhibiting the formation of the membrane contact sites between LDs and RCs or inhibition of the lipolysis pathway disrupts RC biogenesis and enterovirus replication. Our data illuminate mechanistic and functional aspects of organelle remodeling in viral infection and establish that pharmacological targeting of contact sites linking viral and host compartments is a potential strategy for antiviral development.

SUBMITTER: Laufman O

PROVIDER: S-EPMC7077330 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Viral Generated Inter-Organelle Contacts Redirect Lipid Flux for Genome Replication.

Laufman Orly O Perrino John J Andino Raul R

Cell 20190613 2

Positive-stranded RNA viruses extensively remodel host cell architecture to enable viral replication. Here, we examined the poorly understood formation of specialized membrane compartments that are critical sites for the synthesis of the viral genome. We show that the replication compartments (RCs) of enteroviruses are created through novel membrane contact sites that recruit host lipid droplets (LDs) to the RCs. Viral proteins tether the RCs to the LDs and interact with the host lipolysis machi ...[more]

PMID: 31204099

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