Microbiology Commons^™

Contribution Of The Gp120 V3 Loop To Envelope Glycoprotein Trimer Stability In Primate Immunodeficiency Viruses, Dane Bowder, Haley Hollingsead, Kate Durst, Duoyi Hu, Wenzhong Wei, Joshua Wiggins, Halima Medjahed, Andrés Finzi, Joseph Sodroski, Shi-Hua Xiang

Nebraska Center for Virology: Faculty Publications

The V3 loop of the human immunodeficiency virus type 1 (HIV-1) gp120 exterior envelope glycoprotein (Env) becomes exposed after CD4 binding and contacts the coreceptor to mediate viral entry. Prior to CD4 engagement, a hydrophobic patch located at the tip of the V3 loop stabilizes the non-covalent association of gp120 with the Env trimer of HIV-1 subtype B strains. Here, we show that this conserved hydrophobic patch (amino acid residues 307, 309 and 317) contributes to gp120-trimer association in HIV-1 subtype C, HIV-2 and SIV. Changes that reduced the hydrophobicity of these V3 residues resulted in increased gp120 shedding and …

Ultrastructure Of Meelsvirus: A Nuclear Virus Of Arrow Worms (Phylum Chaetognatha) Producing Giant "Tailed" Virions, George L. Shinn, Brianna L. Bullard

Nebraska Center for Virology: Faculty Publications

Most known giant viruses, i.e., viruses producing giant virions, parasitize amoebae and other unicellular eukaryotes. Although they vary in the level of dependence on host nuclear functions, their virions self-assemble in the host cell's cytoplasm. Here we report the discovery of a new prototype of giant virus infecting epidermal cells of the marine arrow worm Adhesisagitta hispida. Its 1.25 μm-long virions self-assemble and accumulate in the host cell's nucleus. Conventional transmission electron microscopy reveals that the virions have a unique bipartite structure. An ovoid nucleocapsid, situated in a broad "head" end of the virion is surrounded by a thin …

Development Of A Broadly Protective Modified-Live Virus Vaccine Candidate Against Porcine Reproductive And Respiratory Syndrome Virus, Haiyan Sun, Aspen Workman, Fernando A. Osorio, David J. Steffen, Hiep L.X. Vu

Nebraska Center for Virology: Faculty Publications

Modified-live virus (MLV) vaccines are widely used to protect pigs against porcine reproductive and respiratory syndrome virus (PRRSV). However, current MLV vaccines do not confer adequate levels of heterologous protection, presumably due to the substantial genetic diversity of PRRSV isolates circulating in the field. To overcome this genetic variation challenge, we recently generated a synthetic PRRSV strain containing a consensus genomic sequence of PRRSV-2. We demonstrated that our synthetic PRRSV strain confers unprecedented levels of heterologous protection. However, the synthetic PRRSV strain at passage 1 (hereafter designated CON-P1) is highly virulent and therefore, is not suitable to be used as …

Efficacy Of An Adenoviral Vectored Multivalent Centralized Influenza Vaccine, Amy Lingel, Brianna L. Bullard, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

Mice were immunized with Adenovirus expressing the H1-con, H2-con, H3-con and H5-con HA consensus genes in combination (multivalent) and compared to mice immunized with the traditional 2010–2011 FluZone and FluMist seasonal vaccines. Immunized mice were challenged with 10–100 MLD50 of H1N1, H3N1, H3N2 and H5N1 influenza viruses. The traditional vaccines induced robust levels of HA inhibition (HI) titers, but failed to protect against five different heterologous lethal influenza challenges. Conversely, the multivalent consensus vaccine (1 × 1010 virus particles (vp)/mouse) induced protective HI titers of ≥40 against 8 of 10 influenza viruses that represent a wide degree of divergence within …

Characterization Of Different Molecular Markers For Identification Of Salmonella Enterica Serovar Typhi In Pakistani Population, Faizan Muttiullah, Fida Muhammad Khan, Fakhar-I- Abbas, Sabiha Shamim

Journal of Bioresource Management

Typhoid is caused by Salmonella enterica serovar Typhi that is usually diagnosed by using serologic and immuno-chromatographic techniques in developing counties including Pakistan, which is thought to be an unreliable diagnostic method. For accurate diagnosis we used molecular techniques to amplify 204 bp StyR-36 and 498 bp flagellin gene for the identification of Salmonella enterica serovar Typhi. This study was done on 58 individuals diagnosed positive of typhoid via serologic tests and 50 healthy individuals as a control group. Success rate of amplification for flagellin gene was 77.58% while that for StyR-36 gene was 68.97% showing that flagellin gene primer …

Prevalence Of Kaposi’S Sarcoma-Associated Herpesvirus In Uygur And Han Populations From The Urumqi And Kashgar Regions Of Xinjiang, China, Jun Zheng, Yang Yang, Meng Cui, Zhan-Jun Shu, Li-Li Han, Zhen-Qiu Liu, Charles Wood, Tiejun Zhang, Yan Zeng

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the infectious etiologic agent associated with Kaposi’s sarcoma (KS), primary effusion lymphoma, and multicentric Castleman disease. It has been shown that high KSHV prevalence and high incidence of both classic KS and AIDSassociated KS are found mostly among people of Uygur ethnicity in Xinjiang, while people of Han ethnicity in Xinjiang have a higher KSHV seroprevalence than those of other Han populations in mainland China. However, it is still unclear why there is such geographical and population variation in KSHV distribution in China. In this work, we focused on the populations in the Kashgar region …

Cross-Reactive Immunity To Porcine Reproductive And Respiratory Syndrome Virus And Its Contribution To Protection, Ignacio Correas

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Due to the vast geographical distribution and significant economic losses generated, porcine reproductive and respiratory syndrome virus (PRRSV) can be considered the most important swine pathogen of contemporary times. Current control and eradication strategies against PRRSV have difficulty succeeding because of their complex nature and the absence of an effective vaccine. A major obstacle for PRRSV vaccine development is the broad heterogeneity of the virus, both at the genetic and antigenic level, its rapid evolution, and an incomplete knowledge of the immune responses responsible for clearing the virus from the host. Specifically, how known correlates of protection against PRRSV—neutralizing antibodies …

Relative Contribution Of Porcine Reproductive And Respiratory Syndrome Virus Open Reading Frames 2–4 To The Induction Of Protective Immunity, Katherine Kimpston-Burkgren, Ignacio Correas, Fernando A. Osorio, David Steffen, Asit K. Pattnaik, Ying Fang, Hiep L. X. Vu

Nebraska Center for Virology: Faculty Publications

The minor glycoproteins (GPs) of PRRSV, GP2, GP3, and GP4, form a heterotrimer that is required for viral infectivity, presumably due to its interaction with the key cellular receptor CD163. These 3 GPs are encoded by open reading frames (ORFs) 2a, 3, and 4 (herein referred to as ORFs 2–4), respectively. The goal of this study was to investigate the immunogenicity of the PRRSV-2 minor GPs. Through the use of reverse genetics, a chimeric virus (designated SDFL24) was constructed by replacing ORFs 2–4 of the PRRSV-1 strain SD01-08 with the corresponding genes of the PRRSV-2 strain FL12. While the parental …

Seroprevalence Of Antibodies Against Kaposi's Sarcoma-Associated Herpesvirus Among Hiv-Negative People In China, Tiejun Zhang, Zhenqiu Liu, Jun Wang, Veenu Minhas, Charles Wood, Gary M. Clifford, Na He, Silvia Franceschi

Nebraska Center for Virology: Faculty Publications

Background: Little information on the prevalence of Kaposi’s sarcoma associated herpesvirus (KSHV) among HIV-negative individuals is available from Asia.

Methods: In the present study, we report findings from a new survey of KSHV in 983 HIV-negative male migrants from Shanghai and their combination with previous similar surveys of 600 female migrants, 600 female sex-workers (FSW), 1336 sexually transmitted infection (STI) clinic male patients, 439 intravenous drug-users (IVDU), and 226 men having sex with men (MSM) from China. KSHV-specific antibodies against latent and lytic antigens were assessed using Sf9 and BC3 monoclonal immunofluorescence assay. Age-adjusted prevalence ratios (PR) and 95% confidence …

Lysine Residues Of Interferon Regulatory Factor 7 Affect The Replication And Transcription Activatormediated Lytic Replication Of Kaposi’S Sarcomaassociated Herpesvirus/Human Herpesvirus 8, Tianzheng Zhang, Ying Wang, Li Zhang, Bin Liu, Jinhui Xie, Charles Wood, Jinzhong Wang

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma-associated herpesvirus (KSHV) infection goes through latent and lytic phases, which are controlled by the viral replication and transcription activator (RTA). Upon KSHV infection, the host responds by suppressing RTA-activated lytic gene expression through interferon regulatory factor 7 (IRF-7), a key regulator of host innate immune response. Lysine residues are potential sites for post-translational modification of IRF-7, and were suggested to be critical for its activity. In this study, we analysed the 15 lysine residues for their effects on IRF-7 function by site-directed mutagenesis. We found that some mutations affect the ability of IRF-7 to activate interferon (IFN)-a1 and …

Coccolithoviruses: A Review Of Cross-Kingdom Genomic Thievery And Metabolic Thuggery, Jozef I. Nissimov, António Pagarete, Fangrui Ma, Sean Cody, David D. Dunigan, Susan A. Kimmance, Michael J. Allen

Nebraska Center for Virology: Faculty Publications

Coccolithoviruses (Phycodnaviridae) infect and lyse the most ubiquitous and successful coccolithophorid in modern oceans, Emiliania huxleyi. So far, the genomes of 13 of these giant lytic viruses (i.e., Emiliania huxleyi viruses—EhVs) have been sequenced, assembled, and annotated. Here, we performed an in-depth comparison of their genomes to try and contextualize the ecological and evolutionary traits of these viruses. The genomes of these EhVs have from 444 to 548 coding sequences (CDSs). Presence/absence analysis of CDSs identified putative genes with particular ecological significance, namely sialidase, phosphate permease, and sphingolipid biosynthesis. The viruses clustered into distinct clades, based on their DNA polymerase …

Freshwater Fungal Infections, Dennis J. Baumgardner

Journal of Patient-Centered Research and Reviews

Fungal infections as a result of freshwater exposure or trauma are fortunately rare. Etiologic agents are varied, but commonly include filamentous fungi and Candida. This narrative review describes various sources of potential freshwater fungal exposure and the diseases that may result, including fungal keratitis, acute otitis externa and tinea pedis, as well as rare deep soft tissue or bone infections and pulmonary or central nervous system infections following traumatic freshwater exposure during natural disasters or near-drowning episodes. Fungal etiology should be suspected in appropriate scenarios when bacterial cultures or molecular tests are normal or when the infection worsens or …

Distinct Transcriptome Profiles Of Gag-Specific Cd8+ T Cells Temporally Correlated With The Protection Elicited By Sivδnef Live Attenuated Vaccine, Wuxun Lu, Yanmin Wu, Fangrui Ma, R. Paul Johnson, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

The live attenuated vaccine (LAV) SIVmac239Δnef (SIVΔnef) confers the best protection among all the vaccine modalities tested in rhesus macaque model of HIV-1 infection. This vaccine has a unique feature of time-dependent protection: macaques are not protected at 3±5 weeks post vaccination (WPV), whereas immune protection emerges between 15 and 20 WPV. Although the exact mechanisms of the time-dependent protection remain incompletely understood, studies suggested that both cellular and humoral immunities contribute to this time-dependent protection. To further elucidate the mechanisms of protection induced by SIVΔnef, we longitudinally compared the global gene expression profiles of SIV Gag-CM9+ CD8+ (Gag-specific CD8+) …

Chloroviruses Have A Sweet Tooth, James L. Van Etten, Irina V. Agarkova, David D. Dunigan, Michela Tonetti, Cristina De Castro, Garry A. Duncan

Nebraska Center for Virology: Faculty Publications

Chloroviruses are large double-stranded DNA (dsDNA) viruses that infect certain isolates of chlorella-like green algae. They contain up to approximately 400 protein-encoding genes and 16 transfer RNA (tRNA) genes. This review summarizes the unexpected finding that many of the chlorovirus genes encode proteins involved in manipulating carbohydrates. These include enzymes involved in making extracellular polysaccharides, such as hyaluronan and chitin, enzymes that make nucleotide sugars, such as GDP-L-fucose and GDP-D-rhamnose and enzymes involved in the synthesis of glycans attached to the virus major capsid proteins. This latter process differs from that of all other glycoprotein containing viruses that traditionally use …

Tryptophan 375 Stabilizes The Outer-Domain Core Of Gp120 For Hiv Vaccine Immunogen Design, Duoyi Hu, Dane Bowder, Wenzhong Wei, Jesse Thompson, Mark A. Wilson, Shi-Hua Xiang

Nebraska Center for Virology: Faculty Publications

The outer-domain core of gp120 may serve as a better HIV vaccine immunogen than the full-length gp120 because of its greater stability and immunogenicity. In our previous report, we introduced two disulfide bonds to the outer-domain core of gp120 to fix its conformation into a CD4-bound state, which resulted in a significant increase in its immunogenicity when compared to the wild-type outer-domain core. In this report, to further improve the immunogenicity of the outer-domain core based immunogen, we have introduced a Tryptophan residue at gp120 amino acid sequence position 375 (375S/W). Our data from immunized guinea pigs indeed shows a …

Characterization Of A New Chlorovirus Type With Permissive And Non-Permissive Features On Phylogenetically Related Algal Strains, Cristian F. Quispe, Ahmed Esmael, Olivia Sonderman, Michelle Mcquinn, Irina Agarkova, Mohammed Battah, Garry A. Duncan, David D. Dunigan, Timothy P. L. Smith, Cristina Decastro, Immacolata Speciale, Fangrui Ma, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

A previous report indicated that prototype chlorovirus PBCV-1 replicated in two Chlorella variabilis algal strains, NC64A and Syngen 2-3, that are ex-endosymbionts isolated from the protozoan Paramecium bursaria. Surprisingly, plaque-forming viruses on Syngen 2-3 lawns were often higher than on NC64A lawns from indigenous water samples. These differences led to the discovery of viruses that exclusively replicate in Syngen 2-3 cells, named Only Syngen (OSy) viruses. OSy-NE5, the prototype virus for the proposed new species, had a linear dsDNA genome of 327 kb with 44-nucleotide-long, incompletely base-paired, covalently closed hairpin ends. Each hairpin structure was followed by an identical …

Reactivation Of Hiv-1 Proviruses In Immune-Compromised Mice Engrafted With Human Voa-Negative Cd4+ T Cells, Zhe Yuan, Guobin Kang, Wuxun Lu, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

Background: HIV-1 infection remains incurable on antiretroviral therapy (ART) due to virus latency. To date, enhanced co-culture assays, including viral outgrowth assays (VOA), are commonly used to measure HIV-1 latent reservoirs and evaluate latency-reversing agents (LRAs). However, VOA can only reactivate a small fraction of intact proviruses.

Methods: To explore the utility of NOD scid gamma (NSG) mice as an in vivo model to reactivate HIV-1 proviruses from VOA-negative CD4+ T cells, resting CD4+ T cells from an HIV-1 latently infected individual were isolated and the human CD4+ T cells corresponding to VOA-positive and VOA-negative CD4+ T cells were engrafted …

A Novel Codon-Optimized Siv Gag-Pol Immunogen For Gene-Based Vaccination, Catherine M. Crosby, Eric A. Weaver, Reeti Khare, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Simian immunodeficiency virus (SIV) is a robust pathogen used in non-human primates to model HIV vaccines. SIV encodes a number of potential vaccine targets. By far the largest and most conserved protein target in SIV is its gag-pol protein that bears many epitopes to drive multivalent immune T cell responses. While gag-pol is an attractive antigen, it is only translated after a frame shift between gag and pol with the effect that gag and pol are expressed at an approximate 10/1 ratio. The codon bias of native lentiviral genes are also mismatched with the abundance of tRNAs in mammalian cells …

Mucosal Vaccination By Adenoviruses Displaying Reovirus Sigma 1, Eric A. Weaver, Zenaido T. Camacho, Matthew L. Hillestad, Catherine M. Crosby, Mallory A. Turner, Adam J. Guenzel, Hind J. Fadel, George T. Mercier, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

We previously developed adenovirus serotype 5 (Ad5) vectors displaying the sigma 1 protein from reovirus as mucosal vaccines. Ad5-sigma retargets to JAM-1 and sialic acid, but had 40-fold reduced gene delivery when compared to Ad5. While weaker at transduction, Ad5-sigma generated stronger T cell responses than Ad5 when used for mucosal immunization. New Ad5-fiber-sigma vectors were generated here by varying the number of fiber β-spiral shaft repeats (R) fused between fiber tail and the sigma. Ad5 virions encoding R3, R14, and R20 chimeras were rescued. Increasing chimera length led to their decreasing encapsidation of these proteins in the virions. Ad5-R3 …

The Pseudomonas Aeruginosa Efflux Pump Mexghi-Opmd Transports A Natural Phenazine That Controls Gene Expression And Biofilm Development, Hassan Sakhtah, Leslie Koyama, Yihan Zhang, Diana K. Morales, Blanche Fields, Alexa Price-Whelan, Deborah Hogan

Dartmouth Scholarship

Redox-cycling compounds, including endogenously produced phenazine antibiotics, induce expression of the efflux pump MexGHI-OpmD in the opportunistic pathogen Pseudomonas aeruginosa Previous studies of P. aeruginosa virulence, physiology, and biofilm development have focused on the blue phenazine pyocyanin and the yellow phenazine-1-carboxylic acid (PCA). In P. aeruginosa phenazine biosynthesis, conversion of PCA to pyocyanin is presumed to proceed through the intermediate 5-methylphenazine-1-carboxylate (5-Me-PCA), a reactive compound that has eluded detection in most laboratory samples. Here, we apply electrochemical methods to directly detect 5-Me-PCA and find that it is transported by MexGHI-OpmD in P. aeruginosa strain PA14 planktonic and biofilm cells. We …

Hiv Vaccines: Progress, Limitations And A Crispr/Cas9 Vaccine, Omar A. Garcia Martinez

Biology: Student Scholarship & Creative Works

ABSTRACT: The HIV-1 pandemic continues to thrive due to ineffective HIV-1 vaccines. Historically, the world’s most infectious diseases, such as polio and smallpox, have been eradicated or have come close to eradication due to the advent of effective vaccines. Highly active antiretroviral therapy is able to delay the onset of AIDS but can neither rid the body of HIV-1 proviral DNA nor prevent further transmission. A prophylactic vaccine that prevents the various mechanisms HIV-1 has to evade and attack our immune system is needed to end the HIV-1 pandemic. Recent advances in engineered nuclease systems, like the CRISPR/Cas9 system, have …

Stabilization Of Gp120 Outer Domain For Hiv-1-1 Vaccine Immunogen Design, Duoyi Hu

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

The sole envelope glycoprotein spike on the surface of Human Immunodeficiency Virus (HIV-1) is composed of two subunits: gp120 and gp41. The gp120 consists of three domains: the inner domain, outer domain and bridging sheet, to which the viral primary receptor CD4 binds and induces a conformational change in gp120 to expose the co-receptor binding site. Previous studies have found that the outer domain of gp120 is relatively more stable than the inner domain and bridging sheet. When superimposed, the co-crystal structures of CD4-gp120 complex and VRC01-gp120 complex revealed that the CD4-binding site (CD4-BS) antibody VRC01 actually mainly bound to …

Blastomyces: Why Be Dimorphic?, Dennis J. Baumgardner

Journal of Patient-Centered Research and Reviews

In introducing the infectious disease focus for this edition of the Journal of Patient-Centered Research and Reviews, the author describes the unsolved mysteries surrounding the dimorphic fungus Blastomyces and the related pathogenesis of pulmonary blastomycosis.

Disease-Causing Fungi In Homes And Yards In The Midwestern United States, Dennis J. Baumgardner

Journal of Patient-Centered Research and Reviews

A number of fungal pathogens that may result in a variety of human diseases are found in residential homes and yards. The growth of these microscopic fungi is often favored by particular characteristics of the dwelling and nearby outdoor environment. Evolved virulence factors or increased ability of specific fungi to grow in diverse, and sometimes harsh, microenvironments presented by the domestic environment may promote growth and pathogenesis. Infection may occur by inhalation or direct inoculation and include endemic fungi in addition to opportunistic or emerging species. Systemic or locally aggressive fungal infections are particularly likely and may be life-threatening in …

First Described Case Of Group B Streptococcus Pelvic Abscess In A Patient With No Medical Comorbidities, Paul Tyan, Elias Abi-Khalil, Karthik Dwarki, Gaby N. Moawad

Obstetrics and Gynecology Faculty Publications

Background. Group B Streptococcus is an organism that commonly infects a wide range of hosts including infants in the first week of life, pregnant women, and older age adults as well as adults with underlying medical comorbidities.

Case. Large pelvic abscess in a nonpregnant patient found to be caused by Group B Streptococcuswas treated successfully with IR guided drainage and antibiotics.

Conclusion. Though rare, GBS can still be a cause of invasive infection even in individuals who are nonpregnant and have no underlying comorbidities. Empiric antibiotic coverage for this organism should be kept in mind when treating an abscess.

Lineage-Specific Differences In The Gp120 Inner Domain Layer 3 Of Human And Simian Immunodeficiency Viruses, Shilei Ding, Halima Medjahed, Jérémie Prévost, Mathieu Coutu, Shi-Hua Xiang, Andrés Finzi

Nebraska Center for Virology: Faculty Publications

Binding of HIV-1 and SIV gp120 exterior envelope glycoprotein to CD4 triggers conformational changes in gp120 that promote its interaction with one of the chemokine receptors, usually CCR5, ultimately leading to gp41-mediated virus-cell membrane fusion and entry. We previously described that topological Layers (Layer 1, Layer 2 and Layer 3) in the gp120 inner domain contribute to gp120-trimer association in the unliganded state but also help secure CD4 binding. Relative to Layer 1 of HIV-1 gp120, the SIVmac239 gp120 Layer 1 plays a more prominent role in maintaining gp120-trimer association but is minimally involved in promoting CD4 binding, which could …

Giant Chloroviruses: Five Easy Questions, James L. Van Etten, David Dunigan

Nebraska Center for Virology: Faculty Publications

Chloroviruses are large, icosahedral, dsDNA-containing viruses that replicate in certain unicellular, chlorella-like green algae [1,2]. They exist in freshwater throughout the world with titers as high as thousands of plaque-forming units (PFU) per ml of indigenous water although titers are typically 1–100 PFU/ml. Titers fluctuate during the year with the highest titers typically occurring in the spring and late fall. Known chlorovirus hosts, which are normally symbionts and are often referred to as zoochlorellae, are associated with either the protozoan Paramecium bursaria (Fig 1A), the coelenterate Hydra viridis, or the heliozoan Acanthocystis turfacea. Zoochlorellae are resistant to viruses …

Genetic Barrier To Direct Acting Antivirals In Hcv Sequences Deposited In The European Databank, Dimas Alexandre Kliemann, Cristiane Valle Tovo, Ana Beatriz Gorini Da Veiga, André Luiz Machado, John T. West

Nebraska Center for Virology: Faculty Publications

Background & Aims: Development of resistance results from mutations in the viral genome, and the presence of selective drug pressure leads to the emergence of a resistant virus population. The aim of this study was to analyze the impact of genetic variability on the genetic barrier to drug resistance to DAAs.

Methods: The genetic barrier was quantified based on the number and type of nucleotide mutations required to impart resistance, considering full-length HCV NS3, NS5A and NS5B regions segregated by genotype into subtypes 1a, 1b, 2a, 2b and 3a. This study analyzed 789 NS3 sequences, 708 sequences and 536 NS5B …

Kaposi’S Sarcoma-Associated Herpesvirus Reduces Cellular Myeloid Differentiation Primary-Response Gene 88 (Myd88) Expression Via Modulation Of Its Rna, Amy Lingel, Erica Ehlers, Qianli Wang, Mingxia Cao, Charles Wood, Rongtuan Lin, Luwen Zhang

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma (KS)-associated herpesvirus (KSHV) is a human gammaherpesvirus associated with several human malignancies. The replication and transcription activator (RTA) is necessary and sufficient for the switch from KSHV latency to lytic replication. Interleukin 1 (IL-1) is a major mediator for inflammation and plays an important role in both innate and adaptive immunity. Myeloid differentiation primary response gene 88 (MyD88) is an essential adaptor molecule for IL-1 as well as most Toll-like receptor signaling. In this study, we identified a novel mechanism by which KSHV interferes with host inflammation and immunity. KSHV RTA specifically reduces the steady-state protein levels of …

Nf45 And Nf90 Bind Hiv-1 Rna And Modulate Hiv Gene Expression, Yan Li, Michael Belshan

Nebraska Center for Virology: Faculty Publications

A previous proteomic screen in our laboratory identified nuclear factor 45 (NF45) and nuclear factor 90 (NF90) as potential cellular factors involved in human immunodeficiency virus type 1 (HIV-1) replication. Both are RNA binding proteins that regulate gene expression; and NF90 has been shown to regulate the expression of cyclin T1 which is required for Tat-dependent trans-activation of viral gene expression. In this study the roles of NF45 and NF90 in HIV replication were investigated through overexpression studies. Ectopic expression of either factor potentiated HIV infection, gene expression, and virus production. Deletion of the RNA binding domains of NF45 …