Visualization of hepatitis E virus RNA and proteins in the human liver

Lenggenhager, Daniela; Gouttenoire, Jérôme; Malehmir, Mohsen; Bawohl, Marion; Honcharova-Biletska, Hanna; Kreutzer, Susanne; Semela, David; Neuweiler, Jörg; Hürlimann, Sandra; Aepli, Patrick; Fraga, Montserrat; Sahli, Roland; Terracciano, Luigi; Rubbia‐Brandt, Laura; Müllhaupt, Beat; Sempoux, Christine; Moradpour, Darius; Weber, Achim

doi:10.1016/j.jhep.2017.04.002

Cited by 53 publications

(86 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…For all constructs, over 90% of cells were ORF2-positive indicating that robust replication and expression of viral genome occurred in wt and mt PLC3/HEV-p6 cells (data not shown). As shown in Figure 3A , the wt ORF2 protein displayed mostly a cytoplasmic localization but also a nuclear localization, as recently described (20). Although mutant ORF2 proteins were globally expressed as the wt ORF2 protein, N1 mutants showed a slightly more perinuclear localization ( Figure 3A ), N2 mutants showed a concentrated staining in a spot close to the nucleus ( Figure 3B ) whereas N3 mutants showed a subcellular localization similar to that of wt ORF2 proteins ( Figure 3C ).…”

Section: Resultssupporting

confidence: 84%

“…The level of ORF2i protein expression and its recognition by MAbs were not affected by mutations of N-glycosylation sites, which is in line with the fact that this protein is not glycosylated. However, during our study, we demonstrated that intracellular ORF2 proteins displayed both cytoplasmic and nuclear localization, as recently observed by immunohistochemistry of liver biopsy from patients with hepatitis E (20). By performing differential extractions and detection by western blotting, we demonstrated that the ORF2i protein localized in the nuclear fraction of HEV producing cells.…”

Section: Discussionsupporting

confidence: 87%

“…Since a recent study (20) and our confocal microscopy analyses ( Figure 3 ) suggest that, in addition to its cytoplasmic localization, the ORF2 protein might also translocate into the nucleus of infected cells, we next further characterized this process by WB and immunofluorescence. We prepared cytoplasmic and nuclear extracts from wt and mt PLC3/HEV-p6 cells.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

New insights into the ORF2 capsid protein, a key player of the hepatitis E virus lifecycle

Ankavay

Montpellier

Sayed

et al. 2018

Preprint

View full text Add to dashboard Cite

Importance 46Hepatitis E virus (HEV) infection is the most common cause of acute viral hepatitis 47 worldwide. This infection can become chronic in immunosuppressed patients and cause death 48 in some patients. In our study, we focused on ORF2 viral capsid protein for which we 49 recently identified glycosylated and non-glycosylated forms. The non-glycosylated form, 50 named ORF2i, is the form associated with the infectious particles. The glycosylated forms, 51 named ORF2g and ORF2c, are the major antigens present in HEV-infected patient sera. Here, 52we identified which sites on ORF2g/c proteins are N-glycosylated. We showed that N-53 glycosylation of ORF2 proteins is not involved in the biogenesis of infectious HEV particles. 54We found that ORF2g/c proteins are very stable and are targeted by patient antibodies. We 55 also demonstrated that the ORF2i protein is translocated into the nucleus of infected cells. 56Thus, our study led to new important insights into the molecular mechanisms of ORF2 57 expression. 58

show abstract

Section: Resultssupporting

confidence: 84%

Section: Discussionsupporting

confidence: 87%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

New insights into the ORF2 capsid protein, a key player of the hepatitis E virus lifecycle

Ankavay

Montpellier

Sayed

et al. 2018

Preprint

View full text Add to dashboard Cite

show abstract

“…Because we demonstrated that GBF1 is a cellular factor required for HEV replication, we next analysed GBF1 subcellular localisation in HEV‐replicating PLC3 cells using immunofluorescence confocal microscopy (Figure ). Due to the lack of tools to probe ORF1 protein in HEV‐replicating cells (Lenggenhager et al, ), co‐localisation studies of GBF1 with the HEV replicase could not be performed. Therefore, non‐transfected PLC3 cells and cells transfected with the full‐length infectious p6 clone were co‐stained with antibodies directed against GBF1 and the ORF2 capsid protein.…”

Section: Resultsmentioning

confidence: 99%

Identification of GBF1 as a cellular factor required for hepatitis E virus RNA replication

Farhat

Ankavay

Lebsir

et al. 2017

Cellular Microbiology

Self Cite

View full text Add to dashboard Cite

The hepatitis E virus (HEV) genome is a single-stranded, positive-sense RNA that encodes three proteins including the ORF1 replicase. Mechanisms of HEV replication in host cells are unclear, and only a few cellular factors involved in this step have been identified so far. Here, we used brefeldin A (BFA) that blocks the activity of the cellular Arf guanine nucleotide exchange factors GBF1, BIG1, and BIG2, which play a major role in reshuffling of cellular membranes. We showed that BFA inhibits HEV replication in a dose-dependent manner. The use of siRNA and Golgicide A identified GBF1 as a host factor critically involved in HEV replication. Experiments using cells expressing a mutation in the catalytic domain of GBF1 and overexpression of wild type GBF1 or a BFA-resistant GBF1 mutant rescuing HEV replication in BFA-treated cells, confirmed that GBF1 is the only BFA-sensitive factor required for HEV replication. We demonstrated that GBF1 is likely required for the activity of HEV replication complexes. However, GBF1 does not colocalise with the ORF1 protein, and its subcellular distribution is unmodified upon infection or overexpression of viral proteins, indicating that GBF1 is likely not recruited to replication sites.Together, our results suggest that HEV replication involves GBF1-regulated mechanisms.

show abstract

“…For example, the HCV viral nonstructural protein 5A can be cleaved by activated caspase, which subsequently translocates to nucleus to enhance the transcription of several NF‐κB target genes to inhibit apoptosis . The protein from HEV ORF2 has different forms and could translocate to the cell nucleus . However, whether ORF2 protein is cleaved by the host protease and whether it regulates apoptotic pathway remain to be further studied.…”

Section: The Mutual Interactions Between Hepatitis Viruses and Mitochmentioning

confidence: 99%

Mitochondria in the biology, pathogenesis, and treatment of hepatitis virus infections

Zhang

et al. 2019

Reviews in Medical Virology

View full text Add to dashboard Cite

Summary Hepatitis virus infections affect a large proportion of the global population. The host responds rapidly to viral infection by orchestrating a variety of cellular machineries, in particular, the mitochondrial compartment. Mitochondria actively regulate viral infections through modulation of the cellular innate immunity and reprogramming of metabolism. In turn, hepatitis viruses are able to modulate the morphodynamics and functions of mitochondria, but the mode of actions are distinct with respect to different types of hepatitis viruses. The resulting mutual interactions between viruses and mitochondria partially explain the clinical presentation of viral hepatitis, influence the response to antiviral treatment, and offer rational avenues for novel therapy. In this review, we aim to consider in depth the multifaceted interactions of mitochondria with hepatitis virus infections and emphasize the implications for understanding pathogenesis and advancing therapeutic development.

show abstract

Visualization of hepatitis E virus RNA and proteins in the human liver

Cited by 53 publications

References 29 publications

New insights into the ORF2 capsid protein, a key player of the hepatitis E virus lifecycle

New insights into the ORF2 capsid protein, a key player of the hepatitis E virus lifecycle

Identification of GBF1 as a cellular factor required for hepatitis E virus RNA replication

Mitochondria in the biology, pathogenesis, and treatment of hepatitis virus infections

Contact Info

Product

Resources

About