Corrigendum to "A heterologous prime-boosting strategy with replicating Vaccinia virus vectors and plant-produced HIV-1 Gag/dgp41 virus-like particles" [Virology 507 (2017) 242-256].
Corrigendum to "A heterologous prime-boosting strategy with replicating Vaccinia virus vectors and plant-produced HIV-1 Gag/dgp41 virus-like particles" [Virology 507 (2017) 242-256]. Virology. 2019 Jun 06;: Authors: Meador LR, Kessans SA, Kilbourne J, Kibler KV, Pantaleo G, Esteban M, Blattman JN, Jacobs BL, Mor TS PMID: 31178060 [PubMed - as supplied by publisher] (Source: Virology)
Source: Virology - June 6, 2019 Category: Virology Authors: Meador LR, Kessans SA, Kilbourne J, Kibler KV, Pantaleo G, Esteban M, Blattman JN, Jacobs BL, Mor TS Tags: Virology Source Type: research

Of capsid structure and stability: The partnership between charged residues of E-loop and P-domain of the bacteriophage P22 coat protein.
Abstract Tailed dsDNA bacteriophages and herpesviruses form capsids using coat proteins that have the HK97 fold. In these viruses, the coat proteins first assemble into procapsids, which subsequently mature during DNA packaging. Generally interactions between the coat protein E-loop of one subunit and the P-domain of an adjacent subunit help stabilize both capsomers and capsids. Based on a recent 3.3 Å cryo-EM structure of the bacteriophage P22 virion, E-loop amino acids E52, E59 and E72 were suggested to stabilize the capsid through intra-capsomer salt bridges with the P-domain residues R102, R109 and K11...
Source: Virology - June 2, 2019 Category: Virology Authors: Asija K, Teschke CM Tags: Virology Source Type: research

Detection of highly pathogenic avian influenza A(H5N6) viruses in waterfowl in Bangladesh.
Abstract Bangladesh has reported repeated outbreaks of highly pathogenic avian influenza (HPAI) A(H5) viruses in poultry since 2007. Because of the large number of live poultry markets (LPM) relative to the population density of poultry throughout the country, these markets can serve as sentinel sites for HPAI A(H5) detection. Through active LPM surveillance during June 2016-June 2017, HPAI A(H5N6) viruses along with 14 other subtypes of influenza A viruses were detected. The HPAI A(H5N6) viruses belonged to clade and were likely introduced into Bangladesh around March 2016. Human infections with influenza...
Source: Virology - May 28, 2019 Category: Virology Authors: Yang G, Chowdury S, Hodges E, Rahman MZ, Jang Y, Hossain ME, Jones J, Stark TJ, Di H, Cook PW, Ghosh S, Azziz-Baumgartner E, Barnes JR, Wentworth DE, Kennedy E, Davis CT Tags: Virology Source Type: research

A unique combination adjuvant modulates immune responses preventing vaccine-enhanced pulmonary histopathology after a single dose vaccination with fusion protein and challenge with respiratory syncytial virus.
This study suggests that combination CpG and MPL adjuvant in RSV subunit vaccination might contribute to priming protective immune responses and preventing inflammatory RSV disease after infection. PMID: 31163351 [PubMed - as supplied by publisher] (Source: Virology)
Source: Virology - May 28, 2019 Category: Virology Authors: Lee Y, Ko EJ, Kim KH, Lee YT, Hwang HS, Kwon YM, Graham BS, Kang SM Tags: Virology Source Type: research

Lack of nsP2-specific nuclear functions attenuates chikungunya virus replication both in vitro and in vivo.
Abstract Chikungunya virus (CHIKV) is an important arthritogenic human pathogen that is already circulating in both hemispheres. In the present study, we substituted VLoop, located on the surface of nsP2, by other amino acid sequences. These modifications had deleterious effects on viral nuclear functions and made CHIKV incapable of interfering with the induction of type I interferon and the antiviral response in both mouse and human cells. Importantly, the identified mutations have no significant effects on the synthesis of virus-specific RNAs and viral structural proteins. The designed mutants induced a few orde...
Source: Virology - May 28, 2019 Category: Virology Authors: Meshram CD, Lukash T, Philips AT, Akhrymuk I, Frolova EI, Frolov I Tags: Virology Source Type: research

Profilin2 is required for filamentous actin formation induced by human parainfluenza virus type 2.
Abstract We previously reported that human parainfluenza virus type 2 (hPIV-2) promoted RhoA activation and subsequent filamentous actin (F-actin) formation. Actin-binding proteins, such as profilin and cofilin, are involved in the regulation of F-actin formation by RhoA signaling. In the present study, we identified profilin2 as a key molecule that is involved in hPIV-2-induced F-actin formation. Immunoprecipitation assays demonstrated that hPIV-2 V protein binds to profilin2 but not to profilin1. Mutation of Trp residues within C-terminal region of V protein abolished the binding capacity to profilin2. Depletion...
Source: Virology - May 24, 2019 Category: Virology Authors: Ohta K, Matsumoto Y, Nishio M Tags: Virology Source Type: research

Recombinant vesicular stomatitis virus expressing the spike protein of genotype 2b porcine epidemic diarrhea virus: A platform for vaccine development against emerging epidemic isolates.
Abstract Emerging porcine epidemic diarrhea viruses (PEDVs) have caused large economic losses since 2010, and G2b is the prevalent globally epidemic genotype. Given the fastidious isolation of emerging PEDV in cell culture and difficulties in retaining the isolate infectivity upon further in vitro passage, highly attenuated recombinant vesicular stomatitis virus (rVSVMT) was used as a vector to express the PEDV spike (S) protein, aiming to develop a subunit vaccine against G2b viruses. An S protein with 19 of its cytoplasmic domain amino acids deleted could be incorporated into VSV particles, generating rVSVMT (VS...
Source: Virology - May 21, 2019 Category: Virology Authors: Ke Y, Yu D, Zhang F, Gao J, Wang X, Fang X, Wang H, Sun T Tags: Virology Source Type: research

NSP2 forms viroplasms during Dendrolimus punctatus cypovirus infection.
Abstract Reoviruses are thought to replicate and assemble in special cytoplasmic structures called 'viroplasms'. However, little is known about the viroplasms of the insect reoviruses, the cypoviruses. To investigate the viroplasm of Dendrolimus punctatus cypovirus (DpCPV), all proteins encoded by the 10 genomic segments of DpCPV were expressed in Sf9 cells using the Bac-to-Bac system. The viral nonstructural protein NSP2 formed viroplasm-like dots which showed close apposition with the endoplasmic reticulum and were surrounded by intracellular membranes during transfection. Colocalization and coimmunoprecipitatio...
Source: Virology - May 16, 2019 Category: Virology Authors: Xu C, Wang J, Yang J, Lei C, Hu J, Sun X Tags: Virology Source Type: research

12 novel atypical porcine pestivirus genomes from neonatal piglets with congenital tremors: A newly emerging branch and high prevalence in China.
This study provides novel epidemiological information of APPV in China. PMID: 31103885 [PubMed - as supplied by publisher] (Source: Virology)
Source: Virology - May 3, 2019 Category: Virology Authors: Yan XL, Li YY, He LL, Wu JL, Tang XY, Chen GH, Mai KJ, Wu RT, Li QN, Chen YH, Sun Y, Ma JY Tags: Virology Source Type: research

The ER stress sensor IRE1 and MAP kinase ERK modulate autophagy induction in cells infected with coronavirus infectious bronchitis virus.
In this study, we demonstrate that autophagosome formation and apparent autophagic flux are induced in cells infected with infectious bronchitis virus (IBV) - a gammacoronavirus. Notably, IBV-induced autophagy was dependent on autophagy related 5 (ATG5) but not beclin1 (BECN1), although both are essential proteins in the canonical autophagy pathway. Moreover, the ER stress sensor inositol requiring enzyme 1 (IRE1), but not its substrate X-box protein 1 (XBP1), was also essential for the induction of autophagy during IBV infection. Finally, the anti-apoptotic extracellular signal-regulated kinase 1/2 (ERK1/2) also contribut...
Source: Virology - May 2, 2019 Category: Virology Authors: Fung TS, Liu DX Tags: Virology Source Type: research

Structural basis for catalysis and substrate specificity of a 3C-like cysteine protease from a mosquito mesonivirus.
We present X-ray structures for the CavV 3C-like protease (3CLpro), as a free enzyme and in complex with a peptide aldehyde inhibitor mimicking the P4-to-P1 residues of a natural substrate. The 3CLpro structure (refined to 1.94 Å) shows that the protein forms dimers. The monomers are comprised of N-terminal domains I and II, which adopt a chymotrypsin-like fold, and a C-terminal α-helical domain III. The catalytic Cys-His dyad is assisted by a complex network of interactions involving a water molecule that mediates polar contacts between the catalytic His and a conserved Asp located in the domain II-III junct...
Source: Virology - May 2, 2019 Category: Virology Authors: Kanitz M, Blanck S, Heine A, Gulyaeva AA, Gorbalenya AE, Ziebuhr J, Diederich WE Tags: Virology Source Type: research

Genetics and pathogenicity of H5N6 highly pathogenic avian influenza viruses isolated from wild birds and a chicken in Japan during winter 2017-2018.
Abstract An H5N6 highly pathogenic avian influenza virus (HPAIV) outbreak occurred in poultry in Japan during January 2018, and H5N6 HPAIVs killed several wild birds in 3 prefectures during Winter 2017-2018. Time-measured phylogenetic analyses demonstrated that the Hemagglutinin (HA) and internal genes of these isolates were genetically similar to clade H5N8 HPAIVs in Europe during Winter 2016-2017, and Neuraminidase (NA) genes of the poultry and wild bird isolates were gained through distinct reassortments with AIVs that were estimated to have circulated possibly in Siberia during Summer 2017 and Summer...
Source: Virology - May 2, 2019 Category: Virology Authors: Mine J, Uchida Y, Nakayama M, Tanikawa T, Tsunekuni R, Sharshov K, Takemae N, Sobolev I, Shestpalov A, Saito T Tags: Virology Source Type: research

HIV-1 is more dependent on the K182 capsid residue than HIV-2 for interactions with CPSF6.
Abstract The HIV-1 capsid (CA) utilizes CPSF6 for nuclear entry and integration site targeting. Previous studies demonstrated that the HIV-1 CA C-terminal domain (CTD) contains a highly conserved K182 residue involved in interaction with CPSF6. In contrast, certain HIV-2 strains possess a substitution at this residue (K182R). To assess whether CA-CPSF6 interaction via the CA CTD is conserved among primate lentiviruses, we examined resistance of several HIV-1- and HIV-2-lineage viruses to a truncated form of CPSF6, CPSF6-358. The results demonstrated that viruses belonging to the HIV-2-lineage maintain interaction ...
Source: Virology - April 27, 2019 Category: Virology Authors: Saito A, Ode H, Nohata K, Ohmori H, Nakayama EE, Iwatani Y, Shioda T Tags: Virology Source Type: research

HIV-1 matrix mutations that alter gag membrane binding modulate mature core formation and post-entry events.
Abstract The matrix (MA) domain of HIV-1 Gag directs membrane binding of the Gag precursor polyprotein during the late events of virus replication. However, the effects of alteration in Gag membrane binding early post-infection are not well understood. To investigate impacts of MA mutations that alter Gag membrane binding on the phenotypes of newly produced virus particles, we extensively characterized two MA mutants by virological, biochemical, and morphological approaches. The V6R mutation, which decreases Gag membrane binding, modified Gag processing and core morphogenesis and impaired core uncoating, reverse t...
Source: Virology - April 27, 2019 Category: Virology Authors: Hikichi Y, Takeda E, Fujino M, Nakayama E, Matano T, Murakami T Tags: Virology Source Type: research

A nuclear envelop-associated baculovirus protein promotes intranuclear lipid accumulation during infection.
Abstract Although it has been well-accepted that baculoviruses produce a virus envelop within the nucleus, the redistribution of membrane lipids in infected cells has not been demonstrated. Here, we characterize a baculovirus protein (Bm5/Ac13: renamed BION; baculovirus protein associated with both the inner- and outer nuclear membranes) that localizes to both the inner- and outer nuclear membranes and show that the nuclear membrane (NE) protein promotes formation of a virus-induced intranuclear structure, the peristromal region (PR). Consistent with its role in virus envelopment, the PR was found to contain viral...
Source: Virology - April 25, 2019 Category: Virology Authors: Nagamine T, Inaba T, Sako Y Tags: Virology Source Type: research

Cytoplasmic R-peptide of murine leukemia virus envelope protein negatively regulates its interaction with the cell surface receptor.
In this study, we found that R-peptide-containing Env protein of E-MLV binds to the cell surface receptor cationic amino acid transporter-1 (CAT-1) with weaker affinity than R-peptide-truncated Env protein. Consistent with this result, R-peptide-containing Env protein had less efficient inhibition of E-MLV vector infection than R-peptide-truncated Env protein. R-peptide truncation has been reported to induce conformational change in the surface subunit of E-MLV Env protein that interacts with the receptor. Taken together, our findings indicate that R-peptide truncation induces conformational change in the receptor-binding ...
Source: Virology - April 23, 2019 Category: Virology Authors: Kubo Y, Izumida M, Togawa K, Zhang F, Hayashi H Tags: Virology Source Type: research

In vitro, in cellulo and structural characterizations of the interaction between the integrase of Porcine Endogenous Retrovirus A/C and proteins of the BET family.
ort C Abstract Retroviral integrase (IN) proteins catalyze the permanent integration of the viral genome into host DNA. They can productively recruit cellular proteins, and the human Bromodomain and Extra-Terminal domain (hBET) proteins have been shown to be co-factors for integration of gamma-retroviruses such as Murine Leukemia Virus (MLV) into human cells. By using two-hybrid, co-immunoprecipitation and in vitro interaction assays, we showed that IN of the gamma- Porcine Endogenous Retrovirus-A/C (PERV IN) interacts through its C-terminal domain (CTD) with hBET proteins. We observed that PERV IN interacts with ...
Source: Virology - April 16, 2019 Category: Virology Authors: Gallay K, Blot G, Chahpazoff M, Yajjou-Hamalian H, Confort MP, De Boisséson C, Leroux A, Luengo C, Fiorini F, Lavigne M, Chebloune Y, Gouet P, Moreau K, Blanchard Y, Ronfort C Tags: Virology Source Type: research

E3 ligase ASB8 promotes porcine reproductive and respiratory syndrome virus proliferation by stabilizing the viral Nsp1 α protein and degrading host IKKβ kinase.
In this study, we demonstrated that PRRSV Nsp1α interacted with the host E3 ubiquitin ligase ankyrin repeat and SOCS box-containing 8 (ASB8). Specifically, porcine ASB8 promoted K63-linked ubiquitination and increased stability of Nsp1α and boosted PRRSV replication. Moreover, we found that ASB8 was phosphorylated at the N-terminal Ser-31 by host IκB kinase β (IKKβ). In turn, ASB8 facilitated K48-linked ubiquitination and degradation of IKKβ via the ubiquitin-proteasome pathway, resulting in remarkable inhibition of I-kappa-B-alpha (IκBα) and of p65 phosphorylation, consequently...
Source: Virology - April 15, 2019 Category: Virology Authors: Li R, Chen C, He J, Zhang L, Zhang L, Guo Y, Zhang W, Tan K, Huang J Tags: Virology Source Type: research

Identification of a human respiratory syncytial virus phosphoprotein domain required for virus-like-particle formation.
Abstract Perceived inefficiency and inadequate knowledge of the human respiratory syncytial virus (hRSV) assembly process present a hurdle for large-scale production of authentic hRSV virus-like particles (VLPs) for vaccine purposes. We previously established that the matrix protein, phosphoprotein (P), and fusion protein carboxy-terminus were sufficient to generate VLPs that resemble filamentous wildtype hRSV. Here, the contribution of P was examined. By co-expressing matrix, fusion, and modified P proteins, a ser/thr-rich P region (residues 39-57) was found to be critical for VLP formation, whereas the oligomeri...
Source: Virology - April 9, 2019 Category: Virology Authors: Meshram CD, Oomens AGP Tags: Virology Source Type: research

Virus survival and fitness when multiple genotypes and subtypes of influenza A viruses exist and circulate in swine.
Abstract We performed swine influenza virus (SIV) surveillance in Midwest USA and isolated 100 SIVs including endemic and reassortant H1 and H3 viruses with 2009 pandemic H1N1 genes. To determine virus evolution when different genotypes and subtypes of influenza A viruses circulating in the same swine herd, a virus survival experiment was conducted in pigs mimicking field situations. Five different SIVs were used to infect five pigs individually, then two groups of sentinel pigs were introduced to investigate virus transmission. Results showed that each virus replicated efficiently in lungs of each infected pig, b...
Source: Virology - April 9, 2019 Category: Virology Authors: Ma J, Shen H, McDowell C, Liu Q, Duff M, Lee J, Lang Y, Hesse D, Richt JA, Ma W Tags: Virology Source Type: research

Viromes in Xylariaceae fungi infecting avocado in Spain.
era C Abstract Four isolates of Entoleuca sp., family Xylariaceae, Ascomycota, recovered from avocado rhizosphere in Spain were analyzed for mycoviruses presence. For that, the dsRNAs from the mycelia were extracted and subjected to metagenomics analysis that revealed the presence of eleven viruses putatively belonging to families Partitiviridae, Hypoviridae, Megabirnaviridae, and orders Tymovirales and Bunyavirales, in addition to one ourmia-like virus plus other two unclassified virus species. Moreover, a sequence with 98% nucleotide identity to plant endornavirus Phaseolus vulgaris alphaendornavirus 1 has been ...
Source: Virology - April 5, 2019 Category: Virology Authors: Velasco L, Arjona-Girona I, Cretazzo E, López-Herrera C Tags: Virology Source Type: research

Constitutive activation of the canonical NF- κB signaling pathway in EBV-associated gastric carcinoma.
In this study, we comprehensively characterized NF-κB signaling in EBVaGC using qRT-PCR, western blot, immunofluorescence assays, ELISA, and immunohistochemistry staining. NF-κB-signaling inhibitors may inhibit the growth of EBVaGC cells and induce significant apoptosis. IκBα is a key regulatory molecule, and repression of IκBα can contribute to aberrant NF-κB activation. Overexpression of LMP1 and LMP2A in the EBV-negative GC cell line SGC7901 could inhibit the expression of IκBα and induce NF-κB activation. These findings indicate that the canonical NF-κB ...
Source: Virology - April 1, 2019 Category: Virology Authors: Zhang Y, Liu W, Zhang W, Wang W, Song Y, Xiao H, Luo B Tags: Virology Source Type: research

The ability of SAMHD1 to block HIV-1 but not SIV requires expression of MxB.
Abstract SAMHD1 is a human restriction factor known to prevent infection of macrophages, resting CD4+ T cells, and dendritic cells by HIV-1. To test the contribution of MxB to the ability of SAMHD1 to block HIV-1 infection, we created human THP-1 cell lines that were knocked out for expression of MxB, SAMHD1, or both. Interestingly, MxB depletion renders SAMHD1 ineffective against HIV-1 but not SIVmac. We observed similar results in human primary macrophages that were knockdown for the expression of MxB. To understand how MxB assists SAMHD1 restriction of HIV-1, we examined direct interaction between SAMHD1 and Mx...
Source: Virology - March 30, 2019 Category: Virology Authors: Buffone C, Kutzner J, Opp S, Martinez-Lopez A, Selyutina A, Coggings SA, Studdard LR, Ding L, Kim B, Spearman P, Schaller T, Diaz-Griffero F Tags: Virology Source Type: research

Apoptosis as a primary defense mechanism in response to viral infection in invasive fire ant Solenopsis invicta.
Abstract Apoptosis is considered an innate defense mechanism of insect hosts at the early stage of pathogen infection. The present study attempts to determine whether apoptosis is involved in defending the fire ant, Solenopsis invicta from a natural viral pathogen Solenopsis invicta virus 1 (SINV-1). Results of TEM examination and TUNEL assay both revealed the signature of apoptosis in the midgut epithelium of SINV-1-infected fire ant larvae. A time-course study was conducted to monitor changes in the dynamics of SINV-1 viral titers and apoptosis levels in the midgut epithelium of SINV-1-infected larvae. We found ...
Source: Virology - March 28, 2019 Category: Virology Authors: Hsu HW, Chiu MC, Shih CJ, Matsuura K, Yang CS Tags: Virology Source Type: research

Pathogenicity and transmission of virulent Newcastle disease virus from the 2018-2019 California outbreak and related viruses in young and adult chickens.
Abstract In May of 2018, virulent Newcastle disease virus was detected in sick, backyard, exhibition chickens in southern California. Since, the virus has affected 401 backyard and four commercial flocks, and one live bird market in California, and one backyard flock in Utah. The pathogenesis and transmission potential of this virus, along with two genetically related and widely studied viruses, chicken/California/2002 and chicken/Belize/2008, were evaluated in both 3-week- and 62-week-old chickens given a low, medium, or high challenge dose. All three viruses were highly virulent causing clinical signs, killing a...
Source: Virology - March 22, 2019 Category: Virology Authors: Dimitrov KM, Ferreira HL, Pantin-Jackwood MJ, Taylor TL, Goraichuk IV, Crossley BM, Killian ML, Bergeson NH, Torchetti MK, Afonso CL, Suarez DL Tags: Virology Source Type: research

Intranasal IgG4/7 antibody responses protect horses against equid herpesvirus-1 (EHV-1) infection including nasal virus shedding and cell-associated viremia.
In conclusion, protective immunity against EHV-1 infection including prevention of viremia was associated with robust systemic and intranasal IgG4/7 antibodies suggesting immediate virus neutralization at the local site. PMID: 30928700 [PubMed - as supplied by publisher] (Source: Virology)
Source: Virology - March 22, 2019 Category: Virology Authors: Perkins G, Babasyan S, Stout AE, Freer H, Rollins A, Wimer CL, Wagner B Tags: Virology Source Type: research

Human metapneumovirus infection of airway epithelial cells is associated with changes in core metabolic pathways.
Abstract Human metapneumovirus (hMPV) is an important cause of acute lower respiratory tract infections in infants, elderly and immunocompromised individuals. Ingenuity pathway analysis of microarrays data showed that 20% of genes affected by hMPV infection of airway epithelial cells (AECs) were related to metabolism. We found that levels of the glycolytic pathway enzymes hexokinase 2, pyruvate kinase M2, and lactate dehydrogenase A were significantly upregulated in normal human AECs upon hMPV infection, as well as levels of enzymes belonging to the hexosamine biosynthetic and glycosylation pathways. On the other ...
Source: Virology - March 22, 2019 Category: Virology Authors: Zhao Y, Chahar HS, Komaravelli N, Dossumekova A, Casola A Tags: Virology Source Type: research

HPV type 16 E6 and NFX1-123 augment JNK signaling to mediate keratinocyte differentiation and L1 expression.
Abstract The HPV life cycle is differentiation-dependent, with cellular differentiation driving initiation of the late, productive stage of the viral life cycle. Here, we identify a role for the protein NFX1-123 in regulating keratinocyte differentiation and events of the late HPV life cycle. NFX1-123 itself increased with differentiation of epithelial cells. Greater NFX1-123 augmented differentiation marker expression and JNK phosphorylation in differentiating 16E6-expressing human foreskin keratinocytes (16E6 HFKs). This was associated with altered expression of MKK4 and MKK7, upstream kinase regulators of JNK p...
Source: Virology - March 16, 2019 Category: Virology Authors: Levan J, Vliet-Gregg PA, Robinson KL, Matsumoto LR, Katzenellenbogen RA Tags: Virology Source Type: research

Discovery of a highly divergent hepadnavirus in shrews from China.
Abstract Limited sampling means that relatively little is known about the diversity and evolutionary history of mammalian members of the Hepadnaviridae (genus Orthohepadnavirus). An important case in point are shrews, the fourth largest group of mammals, but for which there is limited knowledge on the role they play in viral evolution and emergence. Here, we report the discovery of a novel shrew hepadnavirus. The newly discovered virus, denoted shrew hepatitis B virus (SHBV), is divergent to be considered a new species of Orthohepadnavirus. Phylogenetic analysis revealed that these viruses were usually most closel...
Source: Virology - March 11, 2019 Category: Virology Authors: Nie FY, Tian JH, Lin XD, Yu B, Xing JG, Cao JH, Holmes EC, Ma RZ, Zhang YZ Tags: Virology Source Type: research

A complete protocol for whole-genome sequencing of virus from clinical samples: Application to coronavirus OC43.
, Caboche S Abstract Genome sequencing of virus has become a useful tool for better understanding of virus pathogenicity and epidemiological surveillance. Obtaining virus genome sequence directly from clinical samples is still a challenging task due to the low load of virus genetic material compared to the host DNA, and to the difficulty to get an accurate genome assembly. Here we introduce a complete sequencing and analyzing protocol called V-ASAP for Virus Amplicon Sequencing Assembly Pipeline. Our protocol is able to generate the viral dominant genome sequence starting from clinical samples. It is based on a mu...
Source: Virology - March 9, 2019 Category: Virology Authors: Maurier F, Beury D, Fléchon L, Varré JS, Touzet H, Goffard A, Hot D, Caboche S Tags: Virology Source Type: research

Targeted mutational analysis to unravel the complexity of African horse sickness virus NS3 function in mammalian cells.
Abstract The African horse sickness virus non-structural protein 3 (NS3) is involved in the final stages of infection. To gain insight into the function of different NS3 domains, we generated reverse genetics-derived mutants, each expressing a modified version of the protein. A functional comparison of these mutants to the wild-type virus in mammalian cells indicated the variable contribution of the different domains to the cytopathic effect and in ensuring effective virus trafficking and release. The transmembrane domains were determined as essential mediators of NS3 localisation, as the abnormal processing of th...
Source: Virology - March 9, 2019 Category: Virology Authors: Ferreira-Venter L, Venter E, Theron J, van Staden V Tags: Virology Source Type: research

Local structural changes of the influenza A virus ribonucleoprotein complex by single mutations in the specific residues involved in efficient genome packaging.
Abstract The influenza A virus genome consists of eight single-stranded negative-sense RNA segments. The noncoding regions located at the 3'- and 5'- ends of each segment are necessary for genome packaging, and the terminal coding regions are required to precisely bundle the eight segments. However, the nucleotide residues important for genome bundling are not defined. Here, we introduced premature termination codons in the hemagglutinin (HA) or matrix protein 2 (M2) gene and constructed virus libraries containing random sequences in the terminal coding regions. Using these virus libraries, we identified nucleotid...
Source: Virology - March 7, 2019 Category: Virology Authors: Takizawa N, Ogura Y, Fujita Y, Noda T, Shigematsu H, Hayashi T, Kurokawa K Tags: Virology Source Type: research

Claudin-1 inhibits human parainfluenza virus type 2 dissemination.
Abstract Tight junctions enable epithelial cells to form physical barriers that act as an innate immune defense against respiratory infection. However, the involvement of tight junction molecules in paramyxovirus infections, which include various respiratory pathogens, has not been examined in detail. Human parainfluenza virus type 2 (hPIV2) infects airway epithelial cells and causes respiratory illness. In the present study, we found that hPIV2 infection of cultured cells induces expression of claudin-1 (CLDN1), an essential component of tight junctions. This induction seemed to be intrinsically restricted by V, ...
Source: Virology - March 6, 2019 Category: Virology Authors: Yumine N, Matsumoto Y, Ohta K, Fukasawa M, Nishio M Tags: Virology Source Type: research

Down-regulation of hepatitis delta virus super-infection in the woodchuck model.
This study analyzed in detail profound down-regulation of HDV infection in the woodchuck model. Super-infection with HDV of woodchucks chronically infected with HBV-related woodchuck hepatitis virus produced two patterns. In the first, HDV viremia had a sharp peak followed by a considerable decline, and initial rise of HDV virions' infectivity followed by abrupt infectivity loss. In the second, HDV titer rose and later displayed plateau-like profile with high HDV levels; and HDV infectivity became persistently high when HDV titer reached the plateau. The infectivity loss was not due to defects in the virions' envelope, bin...
Source: Virology - March 4, 2019 Category: Virology Authors: Lukash T, Freitas N, Menne S, Gudima SO Tags: Virology Source Type: research

A high-throughput screen for genes essential for PRRSV infection using a piggyBac-based system.
This study not only assists in identifying the genes essential for PRRSV infection but also confirms the possibility of using the piggyBac system to study other virus-host genetic interactions in a high-throughput manner. PMID: 30852268 [PubMed - as supplied by publisher] (Source: Virology)
Source: Virology - March 4, 2019 Category: Virology Authors: Bai J, Li K, Tang W, Liang Z, Wang X, Feng W, Zhang S, Ren L, Wu S, Han H, Zhao Y Tags: Virology Source Type: research

Mosquito cells persistently infected with dengue virus produce viral particles with host-dependent replication.
gel RM, Salas-Benito JS Abstract Dengue viruses (DENV) are important arboviruses that can establish a persistent infection in its mosquito vector Aedes. Mosquitoes have a short lifetime in nature which makes trying to study the processes that take place during persistent viral infections in vivo. Therefore, C6/36 cells have been used to study this type of infection. C6/36 cells persistently infected with DENV 2 produce virions that cannot infect BHK -21 cells. We hypothesized that the following passages in mosquito cells have a deleterious impact on DENV fitness in vertebrate cells. Here, we demonstrated that the ...
Source: Virology - February 27, 2019 Category: Virology Authors: Reyes-Ruiz JM, Osuna-Ramos JF, Bautista-Carbajal P, Jaworski E, Soto-Acosta R, Cervantes-Salazar M, Angel-Ambrocio AH, Castillo-Munguía JP, Chávez-Munguía B, De Nova-Ocampo M, Routh A, Del Ángel RM, Salas-Benito JS Tags: Virology Source Type: research

Genomic characteristics and pathogenicity of natural recombinant porcine reproductive and respiratory syndrome virus 2 harboring genes of a Korean field strain and VR-2332-like strain.
This study demonstrates the genomic characteristics and pathogenicity of natural recombinant PRRSV-2, illustrating the potential importance of recombination in the field. PMID: 30798067 [PubMed - as supplied by publisher] (Source: Virology)
Source: Virology - February 13, 2019 Category: Virology Authors: Kwon T, Yoo SJ, Park JW, Kang SC, Park CK, Lyoo YS Tags: Virology Source Type: research

The cryo-electron microscopy structure of Broad Bean Stain Virus suggests a common capsid assembly mechanism among comoviruses.
We present here the cryo-electron microscopy reconstruction of the BBSV and an atomic model of the capsid proteins refined at 3.22 Å resolution. We identified residues involved in RNA/capsid interactions revealing a unique RNA genome organization. Inspection of the small coat protein C-terminal domain highlights a maturation cleavage between Leu567 and Leu568 and interactions of the C-terminal stretch with neighbouring small coat proteins within the capsid pentameric turrets. These interactions previously proposed to play a key role in the assembly of the Cowpea mosaic virus suggest a common capsid assembly mechani...
Source: Virology - February 13, 2019 Category: Virology Authors: Lecorre F, Lai-Kee-Him J, Blanc S, Zeddam JL, Trapani S, Bron P Tags: Virology Source Type: research

Identification of Eilat virus and prevalence of infection among Culex pipiens L. populations, Morocco, 2016.
We report the record of a nearly-complete sequence of an alphavirus genome showing 95% identity with EILV during a metagenomic analysis performed on 1488 unblood-fed females and 1076 larvae of the mosquito Culex pipiens captured in Rabat (Morocco). Genetic distance and phylogenetic analyses placed the EILV-Morocco as a variant of EILV. The observed infection rates in both larvae and adults suggested an active circulation of the virus in Rabat and its maintenance in the environment either through vertical transmission or through horizontal infection of larvae in breeding sites. This is the first report of EILV out of Israel...
Source: Virology - February 12, 2019 Category: Virology Authors: Bennouna A, Gil P, El Rhaffouli H, Exbrayat A, Loire E, Balenghien T, Chlyeh G, Gutierrez S, Fihri OF Tags: Virology Source Type: research

Adaptive genetic diversifications among tick-borne encephalitis virus subtypes: A genome-wide perspective.
Abstract Tick-borne encephalitis (TBE) is a severe neurological illness in humans. Tick-borne encephalitis virus (TBEV), the causative agent, can be grouped into Far Eastern, Siberian, and (Western) European subtypes. These subtypes are characterized by diverse vector specificity, host range and clinical manifestations. To provide hints for the decisive genetic factors underlying their epidemic and pathogenic diversities, we performed a genome-wide evolutionary study to evaluate the genetic diversity accompanied with the segregations of TBEV subtypes. The results show that adaptive selection has driven the diversi...
Source: Virology - February 12, 2019 Category: Virology Authors: Li Y, Wang D, Du X Tags: Virology Source Type: research

Discovery of endogenous retroviruses with mammalian envelopes in avian genomes uncovers long-term bird-mammal interaction.
Abstract Endogenous retroviruses (ERVs) arise from the infection and integration of past retroviruses into animal hosts. We performed large-scale genomic mining of 101 avian genomes for discovery of ERVs having none-avian origin and investigated the cross-species transmission events. Phylogenetic analysis of the reverse transcriptase (RT) of polymerase gene (pol) and the transmembrane subunit (TM) of the envelope gene (env) supported that avian ERVs with a mammalian env gene existed in at least 15 avian species and can be divided into two major groups: Group-1 were of recombinant ERVs with an alpha-like pol gene a...
Source: Virology - February 8, 2019 Category: Virology Authors: Chen M, Cui J Tags: Virology Source Type: research

Wild birds do not harbor higher diversity of influenza virus internal genes than poultry.
Abstract Avian influenza A virus (AIV) has threatened global economy and public health. Wild birds have long been thought to serve as the natural reservoir of influenza virus, and thus it is expected that wild birds harbor higher viral diversity than poultry. Yet, this hypothesis has not been formally tested. Here, we assemble a data set of AIV from 75 regions worldwide over 11 years and compare the genetic diversity of wild bird AIV with that of poultry AIV. We find the genetic diversity of the internal genes of AIV in wild birds is not significantly higher than that in poultry. We propose that the unexpected div...
Source: Virology - February 7, 2019 Category: Virology Authors: Zhang T, Zhao H, Wang J, Han GZ Tags: Virology Source Type: research

Mutations present in a low-passage Zika virus isolate result in attenuated pathogenesis in mice.
Abstract Zika virus (ZIKV) infection can result in neurological disorders including Congenital Zika Syndrome in infants exposed to the virus in utero. Pregnant women can be infected by mosquito bite as well as by sexual transmission from infected men. Herein, the variants of ZIKV within the male reproductive tract and ejaculates were assessed in inoculated mice. We identified two non-synonymous variants at positions E-V330L and NS1-W98G. These variants were also present in the passage three PRVABC59 isolate and infectious clone relative to the patient serum PRVABC59 sequence. In subsequent studies, ZIKV E-330L was...
Source: Virology - February 7, 2019 Category: Virology Authors: Duggal NK, McDonald EM, Weger-Lucarelli J, Hawks SA, Ritter JM, Romo H, Ebel GD, Brault AC Tags: Virology Source Type: research

Ambient conditions of elevated temperature and CO2 levels are detrimental to the probabilities of transmission by insects of a Potato virus Y isolate and to its simulated prevalence in the environment.
Abstract Conditions of elevated temperature and CO2 levels [30 °C and 970 parts-per-million (ppm), respectively] reduced the systemic titers of a potato virus Y (PVY) isolate in Nicotiana benthamiana plants, relative to standard conditions (25 °C, ~405 ppm CO2). Under controlled conditions we studied how these growing environments affected the transmission of infection by aphids. Probabilities of transmission of infection by insects that fed on infected donor plants kept at either standard conditions, or at 30 °C and 970 ppm CO2 were both determined and found to positively correlate with tite...
Source: Virology - February 4, 2019 Category: Virology Authors: Del Toro FJ, Choi KS, Rakhshandehroo F, Aguilar E, Tenllado F, Canto T Tags: Virology Source Type: research

The KSHV portal protein ORF43 is essential for the production of infectious viral particles.
d R Abstract Herpesvirus capsid assembly involves cleavage and packaging of the viral genome. The Kaposi's sarcoma-associated herpesvirus (KSHV) open reading frame 43 (orf43) encodes a putative portal protein. The portal complex functions as a gate through which DNA is packaged into the preformed procapsids, and is injected into the cell nucleus upon infection. The amino acid sequence of the portal proteins is conserved among herpesviruses. Here, we generated an antiserum to ORF43 and determined late expression kinetics of ORF43 along with its nuclear localization. We generated a recombinant KSHV mutant, which fai...
Source: Virology - February 1, 2019 Category: Virology Authors: Dünn-Kittenplon DD, Kalt I, Lellouche JM, Sarid R Tags: Virology Source Type: research

NS38 is required for aquareovirus replication via interaction with viral core proteins and host eIF3A.
This study is the first to define that the NS38 is essential to viral replication. Together, our findings indicate that NS38 might function as a mediator by interacting with viral and host cellular components in VIBs during replication. PMID: 30735905 [PubMed - as supplied by publisher] (Source: Virology)
Source: Virology - February 1, 2019 Category: Virology Authors: Zhang J, Guo H, Zhang F, Chen Q, Chang M, Fang Q Tags: Virology Source Type: research

Comparative study of chikungunya Virus-Like Particles and Pseudotyped-Particles used for serological detection of specific immunoglobulin M.
Abstract The incidence of chikungunya virus (CHIKV) infection has increased dramatically in recent decades. Effective diagnostic methods must be available to optimize patient management. IgM-capture Enzyme-Linked Immunosorbent Assay (MAC-ELISA) is routinely used for the detection of specific CHIKV IgM. This method requires inactivated CHIKV viral lysate (VL). The use of viral bioparticles such as Virus-Like Particles (VLPs) and Pseudotyped-Particles (PPs) could represent an alternative to VL. Bioparticles performances were established by MAC-ELISA; physico-chemical characterizations were performed by field-flow fr...
Source: Virology - January 30, 2019 Category: Virology Authors: Theillet G, Martinez J, Steinbrugger C, Lavillette D, Coutard B, Papageorgiou N, Dalbon P, Leparc-Goffart I, Bedin F Tags: Virology Source Type: research

Coxsackievirus B infection induces the extracellular release of miR-590-5p, a proviral microRNA.
Abstract Coxsackievirus B is a significant human pathogen and is a leading cause of myocarditis. We and others have observed that certain enteroviruses including coxsackievirus B cause infected cells to shed extracellular vesicles containing infectious virus. Recent reports have shown that vesicle-bound virus can infect more efficiently than free virus. Though microRNAs are differentially regulated in cells following infection, few have been associated with the vesicles shed from infected cells. Here we report exclusive trafficking of specific microRNAs into viral vesicles compared to vesicles from non-infected ce...
Source: Virology - January 30, 2019 Category: Virology Authors: Germano JF, Sawaged S, Saadaeijahromi H, Andres AM, Feuer R, Gottlieb RA, Sin J Tags: Virology Source Type: research

Role of heparan sulfate in entry and exit of Ross River virus glycoprotein-pseudotyped retroviral vectors.
Abstract Variants of Ross River virus (RRV) that bind to heparan sulfate (HS) were previously selected by serial passaging in cell culture. To explore the effects of mutations that convey HS utilization, we pseudotyped Moloney murine leukemia virus (MoMLV), with the RRV envelope. We substituted amino-acid residues 216 and 218 on RRV-E2-envelope glycoprotein with basic amino-acid residues, because these mutations confer affinity for HS upon RRV. However, T216R-RRV- and N218R-RRV-pseudotyped viruses possessed lower transduction titers, and we demonstrated that HS-affinity impeded release of pseudotyped virus from pr...
Source: Virology - January 29, 2019 Category: Virology Authors: Kesari AS, Sharkey CM, Sanders DA Tags: Virology Source Type: research

Editing the human cytomegalovirus genome with the CRISPR/Cas9 system.
Abstract Human Cytomegalovirus (HCMV) is an opportunistic pathogen that causes substantial disease in neonates and immunocompromised individuals. Reverse genetic analysis of the HCMV genome is a powerful tool to dissect the roles that various viral genes play during infection. However, genetic engineering of HCMV is hampered by both the large size of the HCMV genome and HCMV's slow replication cycle. Currently, most laboratories that genetically engineer HCMV employ Bacterial Artificial Chromosome (BAC) mediated recombineering, which is a relatively lengthy process. We explored an alternative method of producing r...
Source: Virology - January 26, 2019 Category: Virology Authors: King MW, Munger J Tags: Virology Source Type: research