Hydegodfrey7595

onal caspase-dependent but caspase 3-independent cell death and that the mechanism of cell death depends on the genetic composition of the host cell. We also map the enhanced oncolytic properties of r2Reovirus in TNBC to interactions between a type 3 M2 gene segment and type 1 genes. Our data show that understanding the interplay between the host cell environment and the genetic composition of oncolytic viruses is crucial for the development of efficacious viral oncolytics.The ongoing coronavirus disease 2019 (COVID-19) pandemic has caused >20 million infections and >750,000 deaths. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of COVID-19, has been found closely related to the bat coronavirus strain RaTG13 (Bat-CoV RaTG13) and a recently identified pangolin coronavirus (Pangolin-CoV-2020). Here, we first investigated the ability of SARS-CoV-2 and three related coronaviruses to utilize animal orthologs of angiotensin-converting enzyme 2 (ACE2) for cell entry. We found that ACE2 orthologs of a wide range of domestic and wild mammals, including camels, cattle, horses, goats, sheep, cats, rabbits, and pangolins, were able to support cell entry of SARS-CoV-2, suggesting that these species might be able to harbor and spread this virus. In addition, the pangolin and bat coronaviruses, Pangolin-CoV-2020 and Bat-CoV RaTG13, were also found able to utilize human ACE2 and a number of animal-ACE2 orthologs for cell entry, indicating risks of spillover to utilize animal orthologs of the SARS-CoV-2 receptor ACE2 might provide structural insight into improving ACE2-based viral entry inhibitors. In this study, we found that ACE2 orthologs of a wide range of domestic and wild animals can support cell entry of SARS-CoV-2 and three related coronaviruses, providing insights into identifying animal hosts of these viruses. We also developed recombinant ACE2-Ig proteins that are able to potently block these viral infections, providing a promising approach to developing antiviral proteins broadly effective against these distinct coronaviruses.Effective and reliable anti-influenza treatments are acutely needed and passive immunizations using broadly neutralizing anti-influenza monoclonal antibodies (bNAbs) are a promising emerging approach. Because influenza infections are initiated in and localized to the pulmonary tract, and newly formed viral particles egress from the apical side of the lung epithelium, we compared the effectiveness of hemagglutinin (HA) stalk-binding bNAbs administered through the airway (intranasal or via nebulization) versus the systemic route (intraperitoneal or intravenous). Airway deliveries of various bNAbs were 10- to 50-fold more effective than systemic deliveries of the same bNAbs in treating H1N1, H3N2, B/Victoria-, and B/Yamagata-lineage influenza viral infections in mouse models. The potency of airway-delivered anti-HA bNAbs was highly dependent on antiviral neutralization activity, with little dependence on the effector function of the antibody. In contrast, the effectiveness of systemically delivered anti-HA bNAbsulations. Because influenza vaccination can be poorly effective some years, and the immune systems of the most susceptible populations are often compromised, passive immunization treatments using broadly neutralizing antibodies is a promising therapeutic approach. However, large amounts of a single antibody are required for effectiveness when delivered through systemic administration (typically intravenous infusion), precluding the feasible dosing of antibody combinations via this route. The significance of our research is the demonstration that effective therapeutic treatments of multiple relevant influenza types (H1N1, H3N2, and B) can be achieved by airway administration of a single combination of relatively small amounts of three anti-influenza antibodies. This advance exploits the discovery that airway delivery is a more potent way of administering anti-influenza antibodies compared to systemic delivery, making this a feasible and cost-effective therapeutic approach.The cloning of herpesviruses as bacterial artificial chromosomes (BACs) has revolutionized the study of herpesvirus biology, allowing rapid and precise manipulation of viral genomes. Several clinical strains of human cytomegalovirus (HCMV) have been cloned as BACs; however, no low-passage strains of murine CMV (MCMV), which provide a model mimicking these isolates, have been cloned. Here, the low-passage G4 strain of was BAC cloned. G4 carries an m157 gene that does not ligate the natural killer (NK) cell-activating receptor, Ly49H, meaning that unlike laboratory strains of MCMV, this virus replicates well in C57BL/6 mice. This BAC clone exhibited normal replication during acute infection in the spleen and liver but was attenuated for salivary gland tropism. Next-generation sequencing revealed a C-to-A mutation at nucleotide position 188422, located in the 3' untranslated region of sgg1, a spliced gene critical for salivary gland tropism. Repair of this mutation restored tropism for the salivary glands. Transexist as cloned BACs. This study describes the first such low-passage MCMV BAC. This BAC-derived G4 was initially attenuated in vivo, with subsequent full genomic sequencing revealing a novel spliced transcript required for salivary gland tropism. These data suggest that MCMV, like HCMV, undergoes tissue culture adaptation that can limit in vivo growth and supports the use of BAC clones as a way of standardizing viral strains and minimizing interlaboratory strain variation.Both Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) are human gammaherpesviruses and are important in a variety of malignancies. Eph family receptor tyrosine kinase A2 (EphA2) is a cellular receptor for KSHV and EBV. see more Previous studies identified five conserved residues (ELEFN50-54) in the N-terminal domain of KSHV gH that are critical for Eph binding and KSHV infection. However, the specific domains of EBV gH/gL important for EphA2 binding are not well described. We found that the KSHV gH (ELEFN50-54) motif is important for higher KSHV fusion and that EBV gH/gL does not utilize a similar motif for fusion activity. We previously identified that an EBV gL N-glycosylation mutant (gL-N69L/S71V) was hyperfusogenic in epithelial cells but not in B cells. To determine whether this glycosylation site may be the binding region for EphA2, we compared the EphA2 binding activity of EBV gH/gL and the EBV gH/gL-N69L/S71V mutant. We found that EBV gH/gL-N69L/S71V had higher binding affinity for Eand EBV gH/gL that mediate the interaction of these two proteins allowing entry into epithelial cells and found that it differed in compared to the interaction of KSHV gH/gL with EphA2. Our discoveries may uncover new potential interventional strategies that block EBV and KSHV infection of target epithelial cells.The Epstein-Barr virus (EBV) immediate early transactivator Zta plays a key role in regulating the transition from latency to the lytic replication stages of EBV infection. Regulation of Zta is known to be controlled through a number of transcriptional and posttranscriptional events. Here, we show that Zta is targeted for ubiquitin modification and that this can occur in EBV-negative and in EBV-infected cells. Genetic studies show critical roles for both an amino-terminal region of Zta and the basic DNA binding domain of Zta in regulating Zta ubiquitination. Pulse-chase experiments demonstrate that the bulk population of Zta is relatively stable but that at least a subset of ubiquitinated Zta molecules are targeted for degradation in the cell. Mutation of four out of a total of nine lysine residues in Zta largely abrogates its ubiquitination, indicating that these are primary ubiquitination target sites. A Zta mutant carrying mutations at these four lysine residues (lysine 12, lysine 188, lysine 207, and lysills. The ubiquitin modification targets 4 lysine residues on Zta, leading to both mono- and polyubiquitination of Zta. Ubiquitination of Zta affects the protein's stability and likely contributes to the progression of viral lytic replication. The function and fate of Zta may be determined by the specific lysine residue being modified.Maize chlorotic mottle virus (MCMV) combines with a potyvirus in maize lethal necrosis disease (MLND), a serious emerging disease worldwide. To inform resistance strategies, we characterized the translation initiation mechanism of MCMV. We report that MCMV RNA contains a cap-independent translation element (CITE) in its 3' untranslated region (UTR). The MCMV 3' CITE (MTE) was mapped to nucleotides 4164 to 4333 in the genomic RNA. 2'-Hydroxyl acylation analyzed by primer extension (SHAPE) probing revealed that the MTE is a distinct variant of the panicum mosaic virus-like 3' CITE (PTE). Like the PTE, electrophoretic mobility shift assays (EMSAs) indicated that eukaryotic translation initiation factor 4E (eIF4E) binds the MTE despite the absence of an m7GpppN cap structure, which is normally required for eIF4E to bind RNA. Using a luciferase reporter system, mutagenesis to disrupt and restore base pairing revealed that the MTE interacts with the 5' UTRs of both genomic RNA and subgenomic RNA1 via long-distance er to improve resistance strategies against MCMV, we focused on how the MCMV genome is translated, the first step of gene expression by all positive-strand RNA viruses. We identified a structure (cap-independent translation element) in the 3' untranslated region of the viral RNA genome that allows the virus to usurp a host translation initiation factor, eIF4E, in a way that differs from host mRNA interactions with the translational machinery. This difference indicates eIF4E may be a soft target for engineering of-or breeding for-resistance to MCMV.Human immunodeficiency virus type 1 (HIV-1) Vif recruits a cellular ubiquitin ligase complex to degrade antiviral APOBEC3 enzymes (APOBEC3C-H) and PP2A phosphatase regulators (PPP2R5A to PPP2R5E). While APOBEC3 antagonism is the canonical function of HIV-1 Vif, this viral accessory protein is also known to trigger G2/M cell cycle arrest. Vif initiates G2/M arrest by degrading multiple PPP2R5 family members, an activity prevalent among diverse HIV-1 and simian immunodeficiency virus (SIV) isolates. Here, computational protein-protein docking was used to delineate a Vif/CBF-β/PPP2R5 complex in which Vif is predicted to bind the same PPP2R5 surface as physiologic phosphatase targets. This model was tested using targeted mutagenesis of amino acid residues within or adjacent to the putative interface to show loss or retention, respectively, of Vif-induced PPP2R5 degradation activity. Additionally, expression of a peptide that mimics cellular targets of PPP2R5s robustly inhibited Vif-mediated degradation of PPP2R5Aonal approaches are used to test a structural model of the Vif/PPP2R5 complex. In addition, imaging studies are used to show that Vif degrades these PPP2R5 substrates in roughly the same time frame as APOBEC3 degradation and that this activity is prevalent in patient-derived Vif isolates. These studies are important by further defining PPP2R5 proteins as a bona fide substrate of HIV-1 Vif.