Effects of tumor necrosis factor on viral replication and pulmonary inflammation during acute mouse adenovirus type 1 respiratory infection.
Abstract CD8 T cells contribute to effective clearance of mouse adenovirus type 1 (MAV-1) and to virus-induced pulmonary inflammation. We characterized effects of a CD8 T cell effector, TNF, on MAV-1 pathogenesis. TNF inhibited MAV-1 replication in vitro. TNF deficiency or immunoneutralization had no effect on lung viral loads or viral gene expression in mice infected intranasally with MAV-1. Absence of TNF delayed virus-induced weight loss and reduced histological evidence of pulmonary inflammation, although concentrations of proinflammatory cytokines and chemokines in bronchoalveolar lavage fluid (BALF) were not...
Source: Virology - June 21, 2020 Category: Virology Authors: Pant K, Chandrasekaran A, Chang CJ, Vageesh A, Popkov AJ, Weinberg JB Tags: Virology Source Type: research

Diaphorina citri reovirus is most closely related to fijiviruses.
Abstract The Asian citrus psyllid, Diaphorina citri Kuwayama, is an important insect vector of Candidatus Liberibacter asiaticus, the causal agent of Huanglongbing, which is the most destructive disease of citrus worldwide. Sequences for putative Diaphorina citri reovirus (DcRV) were identified from some worldwide populations of D. citri. Here, field surveys indicated that the virus was common in D. citri populations from Hawaii and Fuzhou of PR China. Electron microscopy showed that DcRV virions possessed a typical reovirus-like morphology. The U. S. and Chinese DcRV isolates both showed 10 segments of double-str...
Source: Virology - June 21, 2020 Category: Virology Authors: Chen Q, Nouri S, Zhang Y, Erickson A, Falk BW Tags: Virology Source Type: research

Activation of DNA damage repair factors in HPV positive oropharyngeal cancers.
Abstract The mechanisms regulating viral pathogenesis of human papillomavirus (HPV) associated oropharyngeal squamous cell cancers (OPSCC) are not well understood. In the cervix, activation of DNA damage repair pathways is critical for viral replication but little is known about their role in OPSCC. APOBEC factors have been shown to be increased in OPSCC but the significance of this is unclear. We therefore examined activation of DNA damage and APOBEC factors in HPV-induced OPSCC. Our studies show significantly increased levels of pCHK1, FANCD2, BRCA1, RAD51, pSMC1 and γH2AX foci in HPV-positive samples as c...
Source: Virology - June 21, 2020 Category: Virology Authors: Kono T, Hoover P, Poropatich K, Paunesku T, Mittal BB, Samant S, Laimins LA Tags: Virology Source Type: research

Spondweni virus causes fetal harm in Ifnar1-/- mice and is transmitted by Aedes aegypti mosquitoes.
Abstract Spondweni virus (SPONV) is the most closely related known flavivirus to Zika virus (ZIKV). Its pathogenic potential and vector specificity have not been well defined. SPONV has been found predominantly in Africa, but was recently detected in a pool of Culex quinquefasciatus mosquitoes in Haiti. Here we show that SPONV can cause significant fetal harm, including demise, comparable to ZIKV, in a mouse model of vertical transmission. Following maternal inoculation, we detected infectious SPONV in placentas and fetuses, along with significant fetal and placental histopathology, together suggesting vertical tr...
Source: Virology - June 21, 2020 Category: Virology Authors: Jaeger AS, Weiler AM, Moriarty RV, Rybarczyk S, O'Connor SL, O'Connor DH, Seelig DM, Fritsch MK, Friedrich TC, Aliota MT Tags: Virology Source Type: research

A high-resolution map of bacteriophage ϕX174 transcription.
In this study we used next-generation sequencing to measure the RNA produced from ϕX174 while infecting its host E. coli C. We broadly confirm the past transcriptome model while revealing several interesting deviations from previous knowledge. Additionally, we measure the strength of canonical ϕX174 promoters and terminators and discover both a putative new promoter that may be activated by heat shock sigma factors, as well as rediscover a controversial Rho-dependent terminator. We also provide evidence for the first antisense transcription observed in the Microviridae, identify two promoters that may be involved in gene...
Source: Virology - June 21, 2020 Category: Virology Authors: Logel DY, Jaschke PR Tags: Virology Source Type: research

Plant SNAREs SYP22 and SYP23 interact with Tobacco mosaic virus 126  kDa protein and SYP2s are required for normal local virus accumulation and spread.
Plant SNAREs SYP22 and SYP23 interact with Tobacco mosaic virus 126 kDa protein and SYP2s are required for normal local virus accumulation and spread. Virology. 2020 Aug;547:57-71 Authors: Ibrahim A, Yang X, Liu C, Cooper KD, Bishop BA, Zhu M, Kwon S, Schoelz JE, Nelson RS Abstract Viral proteins often interact with multiple host proteins during virus accumulation and spread. Identities and functions of all interacting host proteins are not known. Through a yeast two-hybrid screen an Arabidopsis thaliana Qa-SNARE protein [syntaxin of plants 23 (AtSYP23)], associated with pre-vacuolar compartment ...
Source: Virology - June 21, 2020 Category: Virology Authors: Ibrahim A, Yang X, Liu C, Cooper KD, Bishop BA, Zhu M, Kwon S, Schoelz JE, Nelson RS Tags: Virology Source Type: research

Lipopolysaccharide restricts murine norovirus infection in macrophages mainly through NF-kB and JAK-STAT signaling pathway.
This study reveals additional insight in host defense against MNV infection. PMID: 32452409 [PubMed - in process] (Source: Virology)
Source: Virology - May 28, 2020 Category: Virology Authors: Yu P, Li Y, Wang Y, Peppelenbosch MP, Pan Q Tags: Virology Source Type: research

An essential N-terminal serine-rich motif in the AAV VP1 and VP2 subunits that may play a role in viral transcription.
Abstract Adeno-associated virus (AAV) is one of the most researched, clinically utilized gene therapy vectors. Though clinical success has been achieved, transgene delivery and expression may be hindered by cellular and tissue barriers. Understanding the role of receptor binding, entry, endosomal escape, cytoplasmic and nuclear trafficking, capsid uncoating, and viral transcription in therapeutic efficacy is paramount. Previous studies have shown that N-terminal regions of the AAV capsid proteins are responsible for endosomal escape and nuclear trafficking, however the mechanisms remain unknown. We identified a hi...
Source: Virology - May 28, 2020 Category: Virology Authors: Robinson TM, Ho ML, Wahlig B, Gough V, Banta A, Reyes Gamas K, Kang B, Lee E, Chen W, Suh J Tags: Virology Source Type: research

An RNA-dependent RNA polymerase inhibitor for tick-borne encephalitis virus.
Abstract Tick-borne encephalitis virus (TBEV) is a medically important representative of the Flaviviridae family. The TBEV genome encodes a single polyprotein, which is co/post-translationally cleaved into three structural and seven non-structural proteins. Of the non-structural proteins, NS5, contains an RNA-dependent RNA polymerase (RdRp) domain that is highly conserved and is responsible for the genome replication. Screening for potential antivirals was done using a hybrid receptor and ligand-based pharmacophore search likely targeting the RdRp domain. For the identification of pharmacophores, a mixture of smal...
Source: Virology - May 28, 2020 Category: Virology Authors: Gejji V, Svoboda P, Stefanik M, Wang H, Salat J, Eyer L, Ruzek D, Fernando S Tags: Virology Source Type: research

The viral suppressor HCPro decreases DNA methylation and activates auxin biosynthesis genes.
In this study, we investigated the molecular mechanism by which helper-component protease (HCPro) encoded by the Tobacco vein banding mosaic virus (TVBMV) activates auxin biosynthesis genes (YUCs) and interferes with the auxin signaling pathway. Our results demonstrated that the viral suppressor HCPro decreased the DNA methylation of dispersed repeats (DRs) within the promoters of YUC1, YUC5 and YUC10 and transcriptional activated these YUC genes targeted by RNA-directed DNA methylation (RdDM), leading to an increase in auxin accumulation in plants. Furthermore, we found that the induction of these YUCs by HCPro was attenu...
Source: Virology - May 28, 2020 Category: Virology Authors: Yang L, Meng D, Wang Y, Wu Y, Lang C, Jin T, Zhou X Tags: Virology Source Type: research

Microbiota-independent antiviral effects of antibiotics on poliovirus and coxsackievirus.
Abstract Coxsackieviruses primarily infect the gastrointestinal tract of humans, but they can disseminate systemically and cause severe disease. Using antibiotic treatment regimens to deplete intestinal microbes in mice, several groups have shown that bacteria promote oral infection with a variety of enteric viruses. However, it is unknown whether antibiotics have microbiota-independent antiviral effects for enteric viruses or whether antibiotics influence extra-intestinal, systemic infection. Here, we examined the effects of antibiotics on systemic enteric virus infection by performing intraperitoneal injections ...
Source: Virology - May 28, 2020 Category: Virology Authors: Woods Acevedo MA, Pfeiffer JK Tags: Virology Source Type: research

Regions of bovine adenovirus-3 IVa2 involved in nuclear/nucleolar localization and interaction with pV.
Abstract Bovine adenovirus-3 (BAdV-3) is a non enveloped, icosahedral DNA virus containing a genome of 34446 bps. The intermediate region of BAdV-3 encodes pIX and IVa2 proteins. Here, we report the characterization of BAdV-3 IVa2. Anti-IVa2 serum detected a 50 kDa protein at 24-48 h post infection in BAdV-3 infected cells. The IVa2 localizes to nucleus and nucleolus of BAdV-3 infected cells. Analysis of mutant IVa2 demonstrated that amino acids 1-25 and 373-448 are required for nuclear and nucleolar localization of IVa2, respectively. The nuclear import of IVa2 utilize importin α -1 of importin nu...
Source: Virology - May 28, 2020 Category: Virology Authors: Woldemariam T, Wang W, Said A, Tikoo SK Tags: Virology Source Type: research

Analysis of the reiteration regions (R1 to R5) of varicella-zoster virus.
Abstract The varicella-zoster virus (VZV) genome, comprises both unique and repeated regions. The genome also includes reiteration regions, designated R1 to R5, which are tandemly repeating sequences termed elements. These regions represent an understudied feature of the VZV genome. The R4 region is duplicated, with one copy in the internal repeat short (IRs) which we designated R4A and a second copy in the terminal repeat short (TRs) termed R4B. We developed primers to amplify and Sanger sequence these regions, including independent amplification of both R4 regions. Reiteration regions from>80 cases of PCR-con...
Source: Virology - May 28, 2020 Category: Virology Authors: Jensen NJ, Depledge DP, Ng TFF, Leung J, Quinlivan M, Radford KW, Folster J, Tseng HF, LaRussa P, Jacobsen SJ, Breuer J, Schmid DS Tags: Virology Source Type: research

Human mastadenovirus-B (HAdV-B)-specific E3-CR1 β and E3-CR1γ glycoproteins interact with each other and localize at the plasma membrane of non-polarized airway epithelial cells.
Human mastadenovirus-B (HAdV-B)-specific E3-CR1β and E3-CR1γ glycoproteins interact with each other and localize at the plasma membrane of non-polarized airway epithelial cells. Virology. 2020 Jul;546:67-78 Authors: Lakshmi Narayan PK, Kajon AE Abstract The E3 region of all simian and human types classified within species Human mastadenovirus B (HAdV-B) encodes two unique highly conserved ORFs of unknown function designated E3-CR1β and E3-CR1γ. We generated a HAdV-3 mutant encoding small epitope tags at the N-termini of both E3-CR1β and E3-CR1γ (HAdV-3 N-tag wt) and a ...
Source: Virology - May 28, 2020 Category: Virology Authors: Lakshmi Narayan PK, Kajon AE Tags: Virology Source Type: research

Aspartic acid at residue 185 modulates the capacity of HP-PRRSV nsp4 to antagonize IFN-I expression.
Abstract In a previous study, we have shown that highly-pathogenic PRRSV (HP-PRRSV) nonstructural protein 4 (nsp4) antagonizes type I IFN expression induced by poly(I:C). Here, we demonstrated that the mutation of Aspartic acid 185 (Asp185) impaired the ability of nsp4 to inhibit IFN-I production induced by poly(I:C). Subsequently, we verified that all the mutants at the residue 185, regardless of amino acid size (including Cys and Ser) and charge (including Glu and Lys), impaired nsp4 catalytic activity. However, when Asp185 in nsp4 was replaced by a similar structure amino acid Asparagine 185 (Asn185), nsp4 stay...
Source: Virology - May 28, 2020 Category: Virology Authors: Wei ZY, Liu F, Li Y, Wang HL, Zhang ZD, Chen ZZ, Feng WH Tags: Virology Source Type: research

Antiviral activity of lycorine against Zika virus in vivo and in vitro.
Abstract The emergence and re-emergence of Zika virus (ZIKV), is a cause for international concern. These highly pathogenic arboviruses represent a serious health burden in tropical and subtropical areas worldwide. Despite these burdens, antiviral therapies do not exist, and inhibitors of ZIKV are therefore urgently needed. To elucidate the anti-ZIKV effect of lycorine, we used reverse transcription-quantitative real-time PCR (qRT-PCR), immunofluorescence, Westernwestern blot, and plaque forming assay to analyse viral RNA (vRNA), viral protein, progeny virus counts, and validated inhibitors in vitro using a variet...
Source: Virology - May 28, 2020 Category: Virology Authors: Chen H, Lao Z, Xu J, Li Z, Long H, Li D, Lin L, Liu X, Yu L, Liu W, Li G, Wu J Tags: Virology Source Type: research

Alfalfa leaf curl virus is transmitted by Aphis craccivora in a highly specific circulative manner.
Abstract Two members of the genus Capulavirus (Geminiviridae) are transmitted by aphids including Alfalfa leaf curl virus (ALCV) transmitted by Aphis craccivora. The capulavirus Euphorbia caput-medusae latent virus was shown here to be transmitted also by A. craccivora, using the population EuphorbiaSA. ALCV was transmissible by several A. craccivora populations including Robinia, but not the EuphorbiaSA population, reflecting a high transmission specificity. Typical of the circulative-persistent mode of transmission, ALCV persists through insect molts. ALCV accumulation and localization were analyzed in whole ins...
Source: Virology - May 28, 2020 Category: Virology Authors: Ryckebusch F, Sauvion N, Granier M, Roumagnac P, Peterschmitt M Tags: Virology Source Type: research

Phylodynamics of sunflower chlorotic mottle virus, an emerging pathosystem.
Abstract Distribution and epidemiological patterns of sunflower chlorotic mottle virus (SCMoV) in sunflower (Helianthus annuus L.) growing areas in Argentina were studied from 2006 to 2017. The virus was detected exclusively in the Pampas region (Entre Ríos, Santa Fe, Córdoba, La Pampa and Buenos Aires provinces). Phylodynamic analyses performed using the coat protein gene of SCMoV isolates from sunflower and weeds dated the most recent common ancestor (MRCA) back to 1887 (HPD95% = 1572-1971), which coincides with the dates of sunflower introduction in Argentina. The MRCA was located in the...
Source: Virology - April 22, 2020 Category: Virology Authors: Cabrera Mederos D, Torres C, Bejerman N, Trucco V, Lenardon S, Leiva Mora M, Giolitti F Tags: Virology Source Type: research

Increased expression of microRNA-155-5p by alveolar type II cells contributes to development of lethal ARDS in H1N1 influenza A virus-infected mice.
Abstract Alveolar type II (ATII) cells are essential to lung function and a primary site of influenza A virus (IAV) replication. Effects of IAV infection on ATII cell microRNA (miR) expression have not been comprehensively investigated. Infection of C57BL/6 mice with 10,000 or 100 pfu/mouse of IAV A/WSN/33 (H1N1) significantly altered expression of 73 out of 1908 mature murine miRs in ATII cells at 2 days post-infection (d.p.i.) and 253 miRs at 6 d.p.i. miR-155-5p (miR-155) showed the greatest increase in expression within ATII cells at both timepoints and the magnitude of this increase correlated with i...
Source: Virology - April 22, 2020 Category: Virology Authors: Woods PS, Doolittle LM, Rosas LE, Nana-Sinkam SP, Tili E, Davis IC Tags: Virology Source Type: research

Ribosomal protein RACK1 enhances translation of poliovirus and other viral IRESs.
Abstract Viruses have evolved strategies to ensure efficient translation using host cell ribosomes and translation factors. In addition to cleaving translation initiation factors required for host cell translation, poliovirus (PV) uses an internal ribosome entry site (IRES). Recent studies suggest that viruses exploit specific ribosomal proteins to enhance translation of their viral proteins. The ribosomal protein receptor for activated C kinase 1 (RACK1), a protein of the 40S ribosomal subunit, was previously shown to mediate translation from the 5' cricket paralysis virus and hepatitis C virus IRESs. Here we fou...
Source: Virology - April 22, 2020 Category: Virology Authors: LaFontaine E, Miller CM, Permaul N, Martin ET, Fuchs G Tags: Virology Source Type: research

Hyper-phosphorylation of nsp2-related proteins of porcine reproductive and respiratory syndrome virus.
In this study, we demonstrate that porcine reproductive and respiratory syndrome virus replicase nsp2, and two nsp2-related -2/-1 frameshifting products, nsp2TF and nsp2N, are hyper-phosphorylated. By mapping phosphorylation sites, we subdivide an extended, previously uncharacterized region, located between the papain-like protease-2 (PLP2) domain and frameshifting site, into three distinct domains. These domains include two large hypervariable regions (HVR) with putative intrinsically disordered structures, separated by a conserved and partly structured interval domain that we defined as the inter-HVR conserved domain (IH...
Source: Virology - March 17, 2020 Category: Virology Authors: Shang P, Yuan F, Misra S, Li Y, Fang Y Tags: Virology Source Type: research

High prevalence of subclinical frog virus 3 infection in freshwater turtles of Ontario, Canada.
;a ST Abstract Ranaviruses have been associated with chelonian mortality. In Canada, the first two cases of ranavirus were detected in turtles in 2018 in Ontario, although a subsequent survey of its prevalence failed to detect additional positive cases. To confirm the prevalence of ranavirus in turtles in Ontario, we used a more sensitive method to investigate if lower level persistent infection was present in the population. Here we report results via a combination of qPCR, PCR, Sanger sequencing and genome sequencing from turtles from across Ontario, with no clinical signs of illness. We found 2 positives with h...
Source: Virology - March 17, 2020 Category: Virology Authors: Carstairs SJ, Kyle CJ, Vilaça ST Tags: Virology Source Type: research

Characterization and evaluation of the pathogenicity of a natural recombinant transmissible gastroenteritis virus in China.
In this study, a TGEV JS2012 strain was isolated from the feces of piglets in Jiangsu Province, China. The phylogenetic analysis showed that TGEV JS2012 was placed between the Purdue and the Miller clusters. Analysis of recombination confirmed that TGEV JS2012 is a natural recombinant strain between Miller M6 and Purdue 115. Similar to Miller M6, virulent Purdue and China strain TS, in S gene the JS2012 maintained genetic integrity and the characteristics of the TGEV virulent strains. In vivo, TGEV JS2012 caused 100% mortality in newborn piglets, indicating the strong pathogenicity of this isolate. These results reveal tha...
Source: Virology - March 6, 2020 Category: Virology Authors: Guo R, Fan B, Chang X, Zhou J, Zhao Y, Shi D, Yu Z, He K, Li B Tags: Virology Source Type: research

Adaptive genetic diversification of Lassa virus associated with the epidemic split of north-central Nigerian and non-Nigerian lineages.
This study highlights the viral L protein could be a determinant factor for the epidemic split. PMID: 32174454 [PubMed - as supplied by publisher] (Source: Virology)
Source: Virology - March 5, 2020 Category: Virology Authors: Li Y, Tian H Tags: Virology Source Type: research

Influenza D virus diverges from its related influenza C virus in the recognition of 9-O-acetylated N-acetyl- or N-glycolyl-neuraminic acid-containing glycan receptors.
Abstract Influenza D virus (IDV) utilizes bovines as a primary reservoir with periodical spillover to other mammalian hosts. By using traditional hemagglutination assay coupled with sialoglycan microarray (SGM) platform and functional assays, we demonstrated that IDV is more efficient in recognizing both 9-O-acetylated N-acetylneuraminic acid (Neu5,9Ac2) and 9-O-acetylated N-glycolylneuraminic acid (Neu5Gc9Ac) than influenza C virus (ICV), a ubiquitous human pathogen. ICV seems to strongly prefer Neu5,9Ac2 over Neu5Gc9Ac. Since Neu5Gc9Ac is different from Neu5,9Ac2 only by an additional oxygen in the group at the ...
Source: Virology - March 3, 2020 Category: Virology Authors: Liu R, Sreenivasan C, Yu H, Sheng Z, Newkirk SJ, An W, Smith DF, Chen X, Wang D, Li F Tags: Virology Source Type: research

Chalcid wasp paleoviruses bridge the evolutionary gap between bracoviruses and nudiviruses.
Abstract Polydnaviruses are obligate mutualists of parasitoid wasps and are divided into two genera, Bracovirus and Ichnovirus. Bracoviruses are thought to originate from a single integration of an ancestral nudivirus into the ancestor of microgastroid complex ~100 million years ago. However, all the known nudiviruses are only distantly related to bracoviruses, and much remains obscure about the origin of bracoviruses. Here we employ a paleovirological method to screen endogenous nudivirus-like elements across arthropods. Interestingly, we identify many endogenous nudivirus-like elements within the genome of Euryt...
Source: Virology - February 16, 2020 Category: Virology Authors: Zhang Y, Wang J, Han GZ Tags: Virology Source Type: research

Transcriptional profiling indicates cAMP-driven reversal of HIV latency in monocytes occurs via transcription factor SP-1.
Abstract Latent HIV reservoir is a major barrier to absolute HIV cure. Studies on latency reversal agents (LRA) have by far focused mainly on CD4+ T-lymphocytes, while myeloid reservoirs remain under-represented despite their persistence and key contribution to HIV pathogenesis. cAMP has been shown to increase HIV-1 transcription in latently-infected monocytes/macrophages. In this communication, we explored the potential of commercially available pharmacological drugs and phosphodiesterase inhibitors to reactivate HIV in latently-infected monocytic cell-line, U1. We showed that increased levels of intracellular cA...
Source: Virology - February 16, 2020 Category: Virology Authors: Moar P, Sushmita K, Kateriya S, Tandon R Tags: Virology Source Type: research

Whitefly HES1 binds to the intergenic region of Tomato yellow leaf curl China virus and promotes viral gene transcription.
Abstract Intergenic region of begomovirus genome is vital to virus replication and viral gene transcription in plants. Previous studies have reported that Tomato yellow leaf curl China virus (TYLCCNV), a begomovirus, is able to accumulate and transcribe in its whitefly vector. However, the viral and host components that participate in begomovirus transcription in whiteflies are hitherto unknown. Using a yeast one-hybrid system, we identified>50 whitefly proteins that interacted with TYLCCNV intergenic region. Dual luciferase analysis revealed that one of the identified proteins, the hairy and enhancer of split ...
Source: Virology - February 16, 2020 Category: Virology Authors: Wang YM, He YZ, Ye XT, He WZ, Liu SS, Wang XW Tags: Virology Source Type: research

TF protein of Sindbis virus antagonizes host type I interferon responses in a palmitoylation-dependent manner.
Abstract Sindbis virus (SINV) produces the small membrane protein TF from the 6K gene via a (-1) programmed ribosomal frameshifting. While several groups have shown that TF-deficient virus exhibits reduced virulence, the mechanism(s) by which this occurs remain unknown. Here, we demonstrate a role for TF in antagonizing the host interferon response. Using wild-type and type 1 interferon receptor-deficient mice and primary cells derived from these animals, we show that TF controls the induction of the host interferon response at early times during infection. Loss of TF production leads to elevated interferon and a ...
Source: Virology - February 16, 2020 Category: Virology Authors: Rogers KJ, Jones-Burrage S, Maury W, Mukhopadhyay S Tags: Virology Source Type: research

T-cell immunoglobulin and mucin (TIM) contributes to the infection of human airway epithelial cells by pseudotype viruses containing Hantaan virus glycoproteins.
Abstract Hantaviruses are rodent-borne hemorrhagic fever viruses leading to serious diseases. Viral attachment and entry represent the first steps in virus transmission and are promising targets for antiviral therapeutic intervention. Here we investigated receptor use in human airway epithelium of the Old and New World hantaviruses Hantaan virus (HTNV) and Andes virus (ANDV). Using a biocontained recombinant vesicular stomatitis virus pseudotype platform, we provide first evidence for a role of the cellular phosphatidylserine (PS) receptors of the T-cell immunoglobulin and mucin (TIM) protein family in HTNV and AN...
Source: Virology - February 9, 2020 Category: Virology Authors: Mayor J, Torriani G, Rothenberger S, Engler O Tags: Virology Source Type: research

Zika virus-spread, epidemiology, genome, transmission cycle, clinical manifestation, associated challenges, vaccine and antiviral drug development.
Abstract Zika Virus (ZIKV) is a Flavivirus transmitted primarily via the bite of infected Aedes aegypti mosquitoes. Globally, 87 countries and territories have recorded autochthonous mosquito-borne transmission of ZIKV as at July 2019 and distributed across four of the six WHO Regions. Outbreaks of ZIKV infection peaked in 2016 and declined substantially throughout 2017 and 2018 in the Americas region. There is the likely risk for ZIKV to spread to more countries. There is also the potential for the re-emergence of ZIKV in all places with prior reports of the virus transmission. The current status of ZIKV transmis...
Source: Virology - February 2, 2020 Category: Virology Authors: Pielnaa P, Al-Saadawe M, Saro A, Dama MF, Zhou M, Huang Y, Huang J, Xia Z Tags: Virology Source Type: research

Poxvirus encoded eIF2 α homolog, K3 family proteins, is a key determinant of poxvirus host species specificity.
In this study, the role of K3 family proteins from poxviruses with distinct host tropisms in determining the virus host range was examined in a vaccinia E3L deletion mutant virus. It was found that K3 orthologs from the species-specific poxviruses (taterapox virus, sheeppox virus, myxoma virus, swinepox virus and yaba monkey tumor virus) restored the virus replication competency in cells derived from their natural hosts or related animal species. Further, it was found that the residues located in the helix insert region of the protein, K45 of vaccinia K3 and Y47 of the sheep poxvirus ortholog 011, are critical for the viru...
Source: Virology - February 1, 2020 Category: Virology Authors: Cao J, Varga J, Deschambault Y Tags: Virology Source Type: research

Transmission dynamics between infected waterfowl and terrestrial poultry: Differences between the transmission and tropism of H5N8 highly pathogenic avian influenza virus (clade 2.3.4.4a) among ducks, chickens and turkeys.
Brookes SM Abstract H5N8 highly-pathogenic avian influenza viruses (HPAIVs, clade 2.3.4.4) have spread globally via migratory waterfowl. Pekin ducks infected with a UK virus (H5N8-2014) served as the donors of infection in three separate cohousing experiments to attempt onward transmission chains to sequentially introduced groups of contact ducks, chickens and turkeys. Efficient transmission occurred among ducks and turkeys up to the third contact stage, with all (100%) birds becoming infected. Introduction of an additional fourth contact group of ducks to the turkey transmission chain demonstrated retention of H...
Source: Virology - February 1, 2020 Category: Virology Authors: Puranik A, Slomka MJ, Warren CJ, Thomas SS, Mahmood S, Byrne AMP, Ramsay AM, Skinner P, Watson S, Everett HE, Núñez A, Brown IH, Brookes SM Tags: Virology Source Type: research

Zika virus NS5 nuclear accumulation is protective of protein degradation and is required for viral RNA replication.
Abstract Zika virus (ZIKV) nonstructural protein 5 (NS5) is a multifunctional protein possessing methyltransferase and RNA-dependent RNA polymerase activities. In the present study, we have carried out an extensive mutagenesis analysis to determine the importance of nuclear localization sequences (NLS) of NS5 in its nuclear accumulation and ZIKV replication. Deletion mutagenesis analysis demonstrated that the bipartite NLS consisting of importin β1 (βNLS) and importin α/β-recognized NLS (α/βNLS) is required for NS5 nuclear accumulation. Deletion of βNLS, α/βNLS, or b...
Source: Virology - February 1, 2020 Category: Virology Authors: Ji W, Luo G Tags: Virology Source Type: research

The use of cells from ANPEP knockout pigs to evaluate the role of aminopeptidase N (APN) as a receptor for porcine deltacoronavirus (PDCoV).
In this study, the biological relevance of APN as a receptor for PDCoV was tested by using CRISPR/Cas9 to knockout the APN gene, ANPEP, in pigs. Porcine alveolar macrophages (PAMs) from ANPEP knockout (KO) pigs showed resistance to PDCoV infection. However, lung fibroblast-like cells, derived from the ANPEP KO PAM cultures, supported PDCoV infection to high levels. The results suggest that APN is a receptor for PDCoV in PAMs but is not necessary for infection of lung-derived fibroblast cells. The infection of the ANPEP KO pigs with PDCoV further confirmed that APN is dispensable as a receptor for PDCoV. PMID: 32056711...
Source: Virology - February 1, 2020 Category: Virology Authors: Stoian A, Rowland RRR, Petrovan V, Sheahan M, Samuel MS, Whitworth KM, Wells KD, Zhang J, Beaton B, Cigan M, Prather RS Tags: Virology Source Type: research

Extracellular vesicles restrict dengue virus fusion in Aedes aegypti cells.
Abstract Aedes aegypti is the primary vector of dengue virus (DENV), and acquires this virus from a vertebrate host during blood feeding. Previous literature has shown that vertebrate blood factors such as complement protein C5a and low-density lipoprotein (LDL) influence DENV acquisition in the mosquito. Here, we show that extracellular vesicles in cell culture medium inhibit DENV infection in mosquito cells. Specifically, extracellular vesicles enter into mosquito cells and inhibit an early stage of infection. Extracellular vesicles had no effect on virus cell attachment or entry. Instead, extracellular vesicles...
Source: Virology - February 1, 2020 Category: Virology Authors: Freitas MN, Marten AD, Moore GA, Tree MO, McBrayer SP, Conway MJ Tags: Virology Source Type: research

Hepatitis E viral infection causes testicular damage in mice.
Abstract Hepatitis E virus (HEV) is the main pathogen of hepatitis E infections with multiple extrahepatic replication sites. The presence of HEV RNA in the semen of infertile males suggests HEV replicates in the male genital tract. However, the mechanism is largely remained elusive. A BALB/c-based animal model was used to evaluate the effects of HEV infection on the testicular damage. HEV RNA was detected in feces, blood and livers from 7 to 28 days post-inoculation (dpi), while was positive in male genital tract from 7 to 70 dpi. Positive signals of HEV antigens were observed in testes, epididymides and seminal ...
Source: Virology - February 1, 2020 Category: Virology Authors: Situ J, Wang W, Long F, Yang W, Yang C, Wei D, Yu W, Huang F Tags: Virology Source Type: research

Comparative analysis of the viral interferon regulatory factors of KSHV for their requisite for virus production and inhibition of the type I interferon pathway.
Abstract Unique among human viruses, Kaposi's sarcoma-associated herpesvirus (KSHV) encodes several homologs of cellular interferon regulatory factors (vIRFs). Since KSHV expresses multiple factors that can inhibit interferon (IFN) signaling to promote virus production, it is still unclear to what extent vIRFs contribute to these specific processes during KSHV infection. To study the function of vIRFs during viral infection, we engineered 3xFLAG-tagged-vIRF and vIRF-knockout recombinant KSHV clones, which were utilized to test vIRF expression, as well as their requirement for viral replication, virus production, a...
Source: Virology - February 1, 2020 Category: Virology Authors: Golas G, Jang SJ, Naik NG, Alonso JD, Papp B, Toth Z Tags: Virology Source Type: research

Zika virus NS5 localizes at centrosomes during cell division.
Abstract Zika virus (ZIKV) nonstructural protein 5 (NS5) plays a critical role in viral RNA replication and mediates key virus-host cell interactions. As with other flavivirus NS5 proteins, ZIKV NS5 is primarily found in the nucleus. We previously reported that the NS5 protein of dengue virus, another flavivirus, localized to centrosomes during cell division. Here we show that ZIKV NS5 also relocalizes from the nucleus to centrosomes during mitosis. In infected cells with supernumerary centrosomes, NS5 was present at all centrosomes. Transient expression of NS5 in uninfected cells confirmed that centrosomal locali...
Source: Virology - February 1, 2020 Category: Virology Authors: Kesari AS, Heintz VJ, Poudyal S, Miller AS, Kuhn RJ, LaCount DJ Tags: Virology Source Type: research

MiR-BART1-5p targets core 2 β-1,6-acetylglucosaminyltransferase GCNT3 to inhibit cell proliferation and migration in EBV-associated gastric cancer.
In conclusion, both miR-BART1-5p and knockdown of GCNT3 inhibited cell proliferation and migration. In addition, EBV may regulate GCNT3 by affecting the NF-kB signaling pathway. E-cadherin, N-cadherin, vimentin, and p-ERK were found to be downstream molecules of the miR-BART1-5p/GCNT3 pathway. PMID: 32056716 [PubMed - in process] (Source: Virology)
Source: Virology - February 1, 2020 Category: Virology Authors: Liu J, Zhang Y, Liu W, Zhang Q, Xiao H, Song H, Luo B Tags: Virology Source Type: research

CSFV protein NS5A activates the unfolded protein response to promote viral replication.
Abstract Classical swine fever is a world organization for animal health listed disease and is caused by classical swine fever virus (CSFV). CSFV can induced unfolded protein response (UPR) and whether NS5A protein plays a role in this process remains unknown. Here, we demonstrate that CSFV induced all the three signal pathways ATF6, IRE1 and PERK of UPR. Furthermore, this phenomenon may be mediated by the NS5A protein since expression of NS5A alone can achieve the same effect. In the current study, we show that NS5A can interact with GRP78 as measured by using the CO-IP and GST pulldown assays. This interaction p...
Source: Virology - February 1, 2020 Category: Virology Authors: Chengcheng Z, Fuxi Z, Mengjiao G, Baoyang R, Xuefeng W, Yantao W, Xiaorong Z Tags: Virology Source Type: research

Disrupting the association of Autographa californica multiple nucleopolyhedrovirus Ac93 with cellular ESCRT-III/Vps4 hinders nuclear egress of nucleocapsids and intranuclear microvesicles formation.
In this study, we found that Ac93, a baculovirus core protein, contains a conserved MIM1-like motif. Alanine substitutions for six leucine residues in MIM1-like motif revealed that L142, L145, L146, and L149 are required for association of Ac93 with the MIT domain of Vps4. Mutations of these residues also blocked self-association and the association of Ac93 with ESCRT-III proteins or other viral core proteins Ac76 and Ac103, and resulted in a substantial reduction of infectious virus production, less efficient nuclear egress of progeny nucleocapsids, and the defect of intranuclear microvesicles formation. Combined with the...
Source: Virology - February 1, 2020 Category: Virology Authors: Liu T, Li Y, Qiao B, Jiang Y, Ji N, Li Z Tags: Virology Source Type: research

Genetic diversity and phylogeography of Jeju Orthohantavirus (Hantaviridae) in the Republic of Korea.
This study sheds light on the molecular epidemiology, phylogeographic diversity, and virus-host co-divergence of JJUV, ROK. PMID: 32056842 [PubMed - as supplied by publisher] (Source: Virology)
Source: Virology - January 29, 2020 Category: Virology Authors: Lee SH, Kim WK, Park K, No JS, Lee GY, Kim HC, Klein TA, Min MS, Lee SJ, Hwang J, Park MS, Song JW Tags: Virology Source Type: research

A model for the formation of the duplicated enhancers found in polyomavirus regulatory regions.
Abstract When purified from persistent infections, the genomes of most human polyomaviruses contain single enhancers. However, when isolated from productively infected cells from immunocompromised individuals, the genomes of several polyomaviruses contain duplicated enhancers that promote a number of polyoma-based diseases. The mechanism(s) that gives rise to the duplicated enhancers in the polyomaviruses is, however, not known. Herein we propose a model for the duplication of the enhancers that is based on recent advances in our understanding of; 1) the initiation of polyomavirus DNA replication, 2) the formation...
Source: Virology - January 29, 2020 Category: Virology Authors: Witkin AE, Banerji J, Bullock PA Tags: Virology Source Type: research

Drosophila melanogaster as a model for arbovirus infection of adult salivary glands.
Abstract Arboviruses are an emerging threat to public health. Arbovirus transmission to vertebrates hinges on dissemination from the arthropod gastrointestinal tract, and ultimately infection of the arthropod salivary glands. Therefore, salivary gland immunity impacts arbovirus transmission; however, these immune responses are poorly understood. Here, we describe the utility of Drosophila melanogaster as a salivary gland infection model. First, we describe the use of a salivary gland-specific driver to launch RNA interference or virus replicon transgenes. Next, we infect flies with an arbovirus panel and find mult...
Source: Virology - January 25, 2020 Category: Virology Authors: Palmer WH, Dittmar M, Gordesky-Gold B, Hofmann J, Cherry S Tags: Virology Source Type: research

Gp4 is a nuclease required for morphogenesis of T4-like bacteriophages.
Abstract An essential step in the morphogenesis of tailed bacteriophages is the joining of heads and tails to form infectious virions. Our understanding of the maturation of complete virus particles remains incomplete. Through an unknown mechanism, phage T4 gene product 4 (gp4) plays an essential role in the head-tail joining step of T4-like phages. Alignment of T4 gp4 homologs identified a type II restriction endonuclease motif. Purified gp4 from both T4 and a marine T4-like bacteriophage, YC, have non-specific nuclease activity in vitro. Mutation of a single conserved amino acid residue in the endonuclease fold ...
Source: Virology - January 18, 2020 Category: Virology Authors: Benler S, Hung SH, Vander Griend JA, Peters GA, Rohwer F, Segall AM Tags: Virology Source Type: research

STING is dispensable during KSHV infection of primary endothelial cells.
Abstract During DNA virus infections, detection of cytosolic DNA by the cGAS-STING pathway leads to activation of IFN-β. Kaposi's Sarcoma Herpesvirus (KSHV), an oncogenic DNA virus, is the etiological agent of Kaposi's Sarcoma, an endothelial cell (EC)-based tumor. To investigate the role of STING during KSHV infection of primary ECs we identified a primary lymphatic EC sample that is defective for STING activation and we also knocked out STING in blood ECs. Ablation of STING in EC does not increase susceptibility to KSHV latent infection nor does it increase KSHV spread after lytic reactivation indicating ST...
Source: Virology - January 15, 2020 Category: Virology Authors: Vogt D, Zaver S, Ranjan A, DiMaio T, Gounder AP, Smith JG, Lagunoff M Tags: Virology Source Type: research

STAT3 activates the anti-apoptotic form of caspase 9 in oncovirus-infected B lymphocytes.
Abstract The cancer-causing Epstein-Barr virus (EBV) activates the transcription factor STAT3 upon infecting B-lymphocytes. STAT3 then activates caspase 7 to degrade cellular claspin, resulting in impaired Chk1 phosphorylation. This blockade of ATR-Chk1 signaling allows EBV-transformed cells to proliferate despite DNA lesions from virus-induced replication stress. In addressing the mechanism of caspase 7 activation, we now report that in newly-infected B-cells, STAT3 transcriptionally activates the initiator caspase, caspase 9. Caspase 9 then activates caspase 7 to impair phosphorylation of Chk1 at S345. Important...
Source: Virology - January 15, 2020 Category: Virology Authors: Koganti S, Burgula S, Bhaduri-McIntosh S Tags: Virology Source Type: research

Drosophila immunity against natural and nonnatural viral pathogens.
Abstract The fruit fly Drosophila melanogaster is extensively used as a model species for molecular biology and genetics. It is also widely studied for its innate immune system to expand our understanding of immune host defenses against numerous pathogens. More precisely, studies using both natural and nonnatural Drosophila pathogens have provided a better perspective of viral infection strategies and immunity processes than any other invertebrate. This has made significant advances in identifying and characterizing the innate immune mechanisms by which hosts can combat viral pathogens. However, in-depth studies o...
Source: Virology - January 15, 2020 Category: Virology Authors: Tafesh-Edwards G, Eleftherianos I Tags: Virology Source Type: research

Field porcine reproductive and respiratory syndrome viruses (PRRSV) attenuated by codon pair deoptimization (CPD) in NSP1 protected pigs from heterologous challenge.
Abstract Two type 2 field porcine reproductive and respiratory syndrome viruses (PRRSV) isolated from PRRS-affected swine farms were attenuated by de-optimization of codon pair bias in NSP1. In 3-week-old pigs infection, the attenuated viruses showed significantly lower replication ability than the original viruses without distinct clinical sign and pathological lesions, which were observed in pig infected with the original viruses. Regarding induction of PRRSV specific immunity, the level of the neutralizing antibodies as well as secretion of IFN-γ-SCs in PBMCs was not different between the attenuated virus...
Source: Virology - January 15, 2020 Category: Virology Authors: Park C, Baek JH, Cho SH, Jeong J, Chae C, You SH, Cha SH Tags: Virology Source Type: research