Dataset Information

Aquareovirus NS80 recruits viral proteins to its inclusions, and its C-terminal domain is the primary driving force for viral inclusion formation.

ABSTRACT: Cytoplasmic inclusion bodies formed in reovirus-infected cells are the sites of viral replication and assembly. Previous studies have suggested that the NS80 protein of aquareovirus may be involved in the formation of viral inclusion bodies. However, it remains unknown whether other viral proteins are involved in the process, and what regions of NS80 may act coordinately in mediating inclusion formation. Here, we observed that globular cytoplasmic inclusions were formed in virus-infected cells and viral proteins NS80 and NS38 colocalized in the inclusions. During transfection, singly expressed NS80 could form cytoplasmic inclusions and recruit NS38 and GFP-tagged VP4 to these structures. Further treatment of cells with nocodazole, a microtubule inhibitor, did not disrupt the inclusion, suggesting that inclusion formation does not rely on microtubule network. Besides, we identified that the region 530-742 of NS80 was likely the minimal region required for inclusion formation, and the C-tail, coiled-coil region as well as the conserved linker region were essential for inclusion phenotype. Moreover, with series deletions from the N-terminus, a stepwise conversion occurred from large condensed cytoplasmic to small nuclear inclusions, then to a diffused intracellular distribution. Notablely, we found that the nuclear inclusions, formed by NS80 truncations (471 to 513-742), colocalized with cellular protein ?-catenin. These data indicated that NS80 could be a major mediator in recruiting NS38 and VP4 into inclusion structures, and the C-terminus of NS80 is responsible for inclusion formation.

SUBMITTER: Shao L

PROVIDER: S-EPMC3570539 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Aquareovirus NS80 recruits viral proteins to its inclusions, and its C-terminal domain is the primary driving force for viral inclusion formation.

Shao Ling L Guo Hong H Yan Li-Ming LM Liu Huan H Fang Qin Q

PloS one 20130212 2

Cytoplasmic inclusion bodies formed in reovirus-infected cells are the sites of viral replication and assembly. Previous studies have suggested that the NS80 protein of aquareovirus may be involved in the formation of viral inclusion bodies. However, it remains unknown whether other viral proteins are involved in the process, and what regions of NS80 may act coordinately in mediating inclusion formation. Here, we observed that globular cytoplasmic inclusions were formed in virus-infected cells a ...[more]

PMID: 23424630

Similar Datasets

Project description:Temperature dependency of viral diseases in ectotherms has been an important scientific issue for decades, while the molecular mechanism behind this phenomenon remains largely mysterious. In this study, deploying infection with grass carp reovirus (GCRV), a double-stranded RNA aquareovirus, as a model system, we demonstrated that the cross talk between HSP70 and outer capsid protein VP7 of GCRV determines temperature-dependent viral entry. Multitranscriptomic analysis identified HSP70 as a key player in the temperature-dependent pathogenesis of GCRV infection. Further biochemical, small interfering RNA (siRNA) knockdown, pharmacological inhibition, and microscopic approaches revealed that the primary plasma membrane-anchored HSP70 interacts with VP7 to facilitate viral entry during the early phase of GCRV infection. Moreover, VP7 functions as a key coordinator protein to interact with multiple housekeeping proteins and regulate receptor gene expression, concomitantly facilitating viral entry. This work illuminates a previously unidentified immune evasion mechanism by which an aquatic virus hijacks heat shock response-related proteins to enhance viral entry, pinpointing targeted preventives and therapeutics for aquatic viral diseases. IMPORTANCE The seasonality of viral diseases in ectotherms is a prevailing phenomenon in the aquatic environment, which causes huge economic losses every year worldwide and hinders sustainable development of the aquaculture industry. Nevertheless, our understanding of the molecular mechanism of how temperature determines the pathogenesis of aquatic viruses remains largely unexplored. In this study, by deploying grass carp reovirus (GCRV) infection as a model system, we demonstrated that temperature-dependent, primarily membrane-localized HSP70 interacts with major outer capsid protein VP7 of GCRV to bridge the virus-host interaction, reshape the host's behaviors, and concomitantly facilitate viral entry. Our work unveils a central role of HSP70 in the temperature-dependent pathogenesis of aquatic viruses and provides a theoretical basis for the formulation of prevention and control strategies for aquatic viral diseases.

Project description:Ebola virus (EBOV) causes severe outbreaks of viral hemorrhagic fever in humans. While virus-host interactions are promising targets for antivirals, there is only limited knowledge regarding the interactions of EBOV with cellular host factors. Recently, we performed a genome-wide siRNA screen that identified the nuclear RNA export factor 1 (NXF1) as an important host factor for the EBOV life cycle. NXF1 is a major component of the nuclear mRNA export pathway that is usurped by many viruses whose life cycles include nuclear stages. However, the role of NXF1 in the life cycle of EBOV, a virus replicating in cytoplasmic inclusion bodies, remains unknown. In order to better understand the role of NXF1 in the EBOV life cycle, we performed a combination of co-immunoprecipitation and double immunofluorescence assays to characterize the interactions of NXF1 with viral proteins and RNAs. Additionally, using siRNA-mediated knockdown of NXF1 together with functional assays, we analyzed the role of NXF1 in individual aspects of the virus life cycle. With this approach we identified the EBOV nucleoprotein (NP) as a viral interaction partner of NXF1. Further studies revealed that NP interacts with the RNA-binding domain of NXF1 and competes with RNA for this interaction. Co-localization studies showed that RNA binding-deficient, but not wildtype NXF1, accumulates in NP-derived inclusion bodies, and knockdown experiments demonstrated that NXF1 is necessary for viral protein expression, but not for viral RNA synthesis. Finally, our results showed that NXF1 interacts with viral mRNAs, but not with viral genomic RNAs. Based on these results we suggest a model whereby NXF1 is recruited into inclusion bodies to promote the export of viral mRNA:NXF1 complexes from these sites. This would represent a novel function for NXF1 in the life cycle of cytoplasmically replicating viruses, and may provide a basis for new therapeutic approaches against EBOV, and possibly other emerging viruses.

Dataset Information

Aquareovirus NS80 recruits viral proteins to its inclusions, and its C-terminal domain is the primary driving force for viral inclusion formation.

Publications

Aquareovirus NS80 recruits viral proteins to its inclusions, and its C-terminal domain is the primary driving force for viral inclusion formation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets