Virology Commons^™

The Developmental Process For Adenoviral Vectored Canine Influenza Vaccines, Nicholas Jeanjaquet

School of Biological Sciences: Dissertations, Theses, and Student Research

Canine Influenza Virus (CIV) is a recently emerged branch of Influenza A virus that is highly infectious in dogs. The first strain was isolated in 2003, and it has quickly become endemic in areas with dense dog populations, most notably in Asia. The proximity of dogs to humans, along with their potential to serve as mixing vessels for reassortment, raises concern for possible zoonotic transmission and a potential human pandemic. Available vaccines are not frequently updated and struggle to prevent the spread of currently circulating strains. This highlights the need for a new and more effective vaccine. We outline the …

Exploring The Interactions Between Sars-Cov-2 And Host Proteins, Sojan Shrestha

School of Biological Sciences: Dissertations, Theses, and Student Research

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the current pandemic, Coronavirus Disease 2019 (COVID-19). SARS-CoV-2 is considered to be of zoonotic origin; it originated in non-human animals and was transmitted to humans. Since the early stage of the pandemic, however, the evidence of transmissions from humans to animals (reverse zoonoses) has been found in multiple animal species including mink, white-tailed deer, and pet and zoo animals. Furthermore, secondary zoonotic events of SARS-CoV-2, transmissions from animals to humans, have been also reported. It is suggested that non-human hosts can act as SARS-CoV-2 reservoirs where accumulated …

Characterization Of Novel Chlorovirus Glycosyltransferases That Synthesize Atypical Glycans, Eric A. Noel

School of Biological Sciences: Dissertations, Theses, and Student Research

Giant dsDNA chloroviruses encode a diverse repertoire of glycosyltransferases (GTases) and methyltransferases (MTases) that biosynthesize unusual, methylated sugars independent of their host chlorella-like green algae prompting a reexamination of glycobiology systems. Unlike most other viruses, the prototype chlorovirus PBCV-1 encodes most, if not all, of the machinery required to glycosylate its major capsid protein (MCP). The structures of the four N-linked glycans do not resemble any other glycans in the three domains of life. Here, we investigated the potential involvement of chlorovirus- encoded putative GTases and MTases in glycosylation of the viral MCP. First, we aimed to generate site-directed …

Polerovirus Genomic Variation And Mechanisms Of Silencing Suppression By P0 Protein, Natalie M. Holste

School of Biological Sciences: Dissertations, Theses, and Student Research

The family Luteoviridae consists of three genera: Luteovirus, Enamovirus, and Polerovirus. The genus Polerovirus contains 32 virus species. All are transmitted by aphids and can infect a wide variety of crops from cereals and wheat to cucurbits and peppers. However, little is known about how this wide range of hosts and vectors developed. In poleroviruses, aphid transmission and virion formation is mediated by the coat protein read-through domain (CPRT) while silencing suppression and phloem limitation is mediated by Protein 0 (P0)—a protein unique to poleroviruses. P0 gives poleroviruses a great advantage amongst plant viruses and diversifies polerovirus species, but the …

Regulation Of Vaccinia Virus Replication: A Story Of Viral Mimicry And A Novel Antagonistic Relationship Between Vaccinia Kinase And Pseudokinase, Annabel T. Olson

School of Biological Sciences: Dissertations, Theses, and Student Research

Poxviruses employ sophisticated signaling pathways that thwart cellular defense mechanisms and simultaneously ensure viral factors are modulated properly. Yet, our understanding of these complex signaling networks are incomplete. For example, the vaccinia B1 kinase plays a vital role in inactivating the cellular antiviral factor BAF, and is suggested to orchestrate other pathways. B1 is highly conserved among poxviruses and exhibits a remarkable degree of similarity to VRKs, a family of cellular kinases, suggesting that the viral enzyme has evolved to mimic VRK activity. Indeed, B1 and VRKs have been demonstrated to target a shared substrate, the DNA binding protein BAF, …

Contributions Of The Gp120 Variable Loops To Envelope Glycoprotein Trimer Stability In Primate Lentiviruses, Dane M. Bowder

School of Biological Sciences: Dissertations, Theses, and Student Research

Human Immunodeficiency Virus (HIV) is the etiological agent of AIDS and is responsible for the AIDS pandemic worldwide. According to UNAIDS, as of 2016, there were approximately 36.7 million people living with HIV globally, and 1.8 million new infections that year. While antiretroviral therapies and education continue to reduce these numbers, a preventative vaccine is still required to curb this epidemic. The envelope glycoprotein trimer of HIV, which is the sole protein on the surface of the virus and facilitates entry of the virus into host cells, is of keen interest to the HIV vaccine and drug-development field. Recently, the …

Evaluation Of A Human Papillomavirus Genotyping Assay For Cervical Cancer Screening In Tanzania, Kandali S. Kapie

School of Biological Sciences: Dissertations, Theses, and Student Research

Abstract: Mucosal high-risk Human papillomavirus (HR-HPV) has been identified as the primary factor in causing cervical cancer, the most common cancer in women of low and middle-income countries (LMICs). Cervical cancer screening, incorporating the HPV test shown to be more advantageous than screening by visual inspection with acetic acid (VIA) alone. However, due to resources constrain these countries could not afford the available HPV tests. We, therefore, validated a cost-effective Multiplex PCR HPV (mPCR) assay, a recently developed assay for detecting sixteen genital HPV, fourteen HR-HPV and 2 low-risk genotypes. We postulate that this HPV multiplex assay will be at …

Identification And Characterization Of Ion Channel Activity Of The M2 Protein From Influenza Virus D (Dm2), Jianing Liu

School of Biological Sciences: Dissertations, Theses, and Student Research

Viral ion channels are membrane proteins of influenza viruses that play essential roles in the replication cycle, which enables them to be targeted by antiviral drugs. M2 of influenza type A virus, BM2 of influenza type B virus, and CM2 from influenza type C virus have been characterized as ion channel proteins and antiviral drug amantadine was developed to control influenza type A virus. However, few studies have been conducted to clarify the properties of the M2 protein (DM2) of influenza type D virus, a novel influenza virus genus identified in 2014. To identify the ion channel activity of DM2, …

A Lipidomics Approach To The Viral–Host Dynamics Of The Unicellular, Eukaryotic Alga Chlorella Variabilis And Its Viral Pathogen, Pbcv-1, Suzanne L. Rose

School of Biological Sciences: Dissertations, Theses, and Student Research

This thesis focuses on the sterol and sphingolipid composition in the unicellular, green alga Chlorella variabilis and the lipidomic changes that occur during viral infection. Using lipid analysis by mass spectrometry, we have identified the major sterol, ergosterol and sphingolipid, glucosyl inositol phosphoceramide (GIPC) as constituents of C. variabilis cell membranes. Sterols and sphingolipids have essential biological functions such as hormone-based signaling, plant defense, and apoptosis as well as critical roles in structural components of the cell and organelle membranes. In chapters two and three, we focus on the characterization of sterol composition among both freshwater and marine alga …

Expansion Of The Chlorovirus Genus By Studies On Virus Natural History And Chlorella Host Metabolism, Cristian F. Quispe

School of Biological Sciences: Dissertations, Theses, and Student Research

Inland waters cover about 2.5 percent of our planet and harbor huge numbers of known and unknown microorganisms including viruses. Viruses likely play dynamic, albeit largely undocumented roles in regulating microbial communities and in recycling nutrients in the ecosystem. Phycodnaviruses are a genetically diverse, yet morphologically similar, group of large dsDNA-containing viruses (160- to 560-kb) that inhabit aquatic environments. Members of the genus Chlorovirus are common in freshwater. They replicate in eukaryotic, single-celled, chlorella-like green algae that normally exist as endosymbionts of protists in nature. Very little is known about the natural history of the chloroviruses and how they achieve …

Kaposi’S Sarcoma-Associated Herpesvirus Transmission And Infection Among Young Zambian Children, Landon N. Olp

School of Biological Sciences: Dissertations, Theses, and Student Research

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the etiologic agent for all forms of Kaposi’s sarcoma (KS)—one of the most common pediatric cancers in sub-Saharan Africa during the AIDS epidemic. KS was endemic in sub-Saharan Africa prior to the HIV/AIDS epidemic, but KS cases drastically increased thereafter. Our laboratory previously observed that KSHV infection is common among Zambian children and saliva is the major route of transmission. However, additional factors associated with the transmission of KSHV to children are poorly understood. Since a vaccine against KSHV is not currently available, it is paramount to understand factors associated with transmission so that alternative …

Chlorovirus Skp1 And Core Ankyrin-Repeat Protein Interplay And Mimicry Of Cellular Ubiquitin Ligase Machinery, Eric Andrew Noel

School of Biological Sciences: Dissertations, Theses, and Student Research

The ubiquitin-proteasome system is a common target of several unrelated viruses that have evolved convergent strategies to redirect host ubiquitin machinery to serve their own needs. Members of the genus Chlorovirus, a group of large dsDNA viruses that infect certain freshwater chlorella-like green algae, encode a conserved Skp1 homolog and ankyrin-repeat (ANK) proteins, some of which contain C-terminal domains characteristic of cellular F-boxes or related viral PRANC domains. These observations suggested that this unique combination of chlorovirus proteins either interact with or imitate the key components of the SCF (Skp1-Cul1-F-box) ubiquitin ligases. Using mass spectrometry, we identified two functional …

Functional Implications Of The Baf–B1 Axis During The Vaccinia Virus Life Cycle, Nouhou Ibrahim

School of Biological Sciences: Dissertations, Theses, and Student Research

Vaccinia virus is the prototypic member of the Poxviridae family, which includes variola virus, the agent of smallpox. Poxviruses encode their own transcriptional machinery and a set of proteins to evade the host defense system, and thus are able to replicate entirely in the cytoplasm of their host. The poxvirus life cycle occurs in sequential stages: early gene expression, DNA replication, intermediate gene expression and then late gene expression and morphogenesis. The temporally staged poxvirus life cycle makes viral DNA replication a required event for post-replicative events to occur. However, viral DNA replication itself depends on an early viral Ser/Thr …

Analysis Of Human Papillomavirus Capsid Proteins: Insights Into Capsid Assembly, Willie A. Hughes

School of Biological Sciences: Dissertations, Theses, and Student Research

Papillomaviruses (PVs) are double stranded (ds)-DNA viruses (~8-kbp), which infect mucosal and cutaneous epithelial cells from various mammalian species, causing tumors in both epithelial cell-types. During the late-phase, the capsid proteins (L1 and L2), are expressed to encapsidate the viral genome generating infectious virion particles required for PV. Natural PV infections produce morphologically homogenous progeny virions 55-nm in diameter. Transient transfection systems allow individual expression of the capsid proteins, which are able to produce low-levels of infectious virion-like particles (VLPs) and non-infectious VLPs that have the capacity to resemble and function as wild-type virions.

Results: The research herein demonstrates …

Evolution Of Human Immunodeficiency Virus Type 1 Clade C Envelope V1–V5 Region During Disease Progression In Non-Human Primate Model, For Yue Tso

School of Biological Sciences: Dissertations, Theses, and Student Research

Human immunodeficiency virus type 1 (HIV-1) clade C strain is the fastest spreading HIV-1 strain globally, especially in Africa. It has been decades since the acquired immune deficiency syndrome (AIDS) pandemic first started. However, an effective anti-HIV-1 vaccine is not yet available, which is partly due to the highly variable nature of HIV-1 envelope gene and the absence of a suitable animal model. Strengthening of the understanding of envelope evolution during disease progression will contribute significantly towards future anti-HIV-1 treatment and preventions.

Non-human primates have been an essential animal model for many biomedical research areas. Using simian-human immunodeficiency virus (SHIV) …

Telomere-Related Factors And Human Papillomavirus Genome Maintenance, Adam J. Rogers

School of Biological Sciences: Dissertations, Theses, and Student Research

Human papillomaviruses (HPVs) are small DNA tumor viruses identified by their characteristic ability to replicate as a nuclear plasmid in mitotically active basal keratinocytes. A key characteristic of the HPV life cycle is the establishment of a stable maintenance phase wherein the virus replicates at low copy number, which likely occurs in cells expressing little to no E1 and E2. It is thought that HPV16 replicates in a once-per-cell-cycle manner during this portion of its life cycle and presumably interacts with host chromosome replication and maintenance factors to facilitate this replication. The adaptive radiation of papillomaviruses in response to changing …

Transcriptional Analysis Of Cervical Epithelial Cell Responses To Hiv-1, Andrew A. Block

School of Biological Sciences: Dissertations, Theses, and Student Research

Human Immunodeficiency Virus type 1 (HIV-1) infection causes a growing pandemic throughout the world, of which women comprise 51% of people who live with HIV-1, more than 60% in sub-Saharan Africa. HIV-1 infections of women are mainly acquired through female reproductive tract where cervical and vaginal epithelial cells are the first line of defense. Although HIV-1 does not directly infect epithelial cells, HIV-1 obligatorily interacts with and crosses over epithelial layer to infect susceptible target cells, mainly CD4+ T cells, in the lamina propria to initiate an infection. However, the mechanism and ramification of the interaction of HIV-1 and epithelial …

Characterization Of Binding And Fusion Efficiencies Mediated By The V1–V5 Env Derived From Transmitted And Non-Transmitted Viruses Isolated From A Perinatal Transmission Cohort From Zambia, Mackenzie Waltke

School of Biological Sciences: Dissertations, Theses, and Student Research

Human Immunodeficiency Virus Type 1 (HIV-1) is the etiological agent of acquired immunodeficiency syndrome (AIDS), which affects over 34 million people worldwide. In sub-Saharan Africa where access to antiretroviral therapies (ART) is limited, mother-to-child transmission (MTCT) rates remain high and represent a major concern in the global HIV/AIDS epidemic. Little is known about the biological properties of viruses that are transmitted perinatally, including how the biological functions of envelope (Env) influence transmissibility. Previously, transmitted viruses were found to have an advantage in replicative fitness mediated by Env V1-V5. In this study viruses derived from transmitting mother infant pairs (MIPs) were …

The Role Of Human Ubc9 During The Human Immunodeficiency Virus Replication Cycle, Christopher R. Bohl

School of Biological Sciences: Dissertations, Theses, and Student Research

Human immunodeficiency virus type 1 (HIV-1) is a retrovirus and the causative agent of the acquired immune deficiency syndrome (AIDS) pandemic. The retrovirus replication cycle is divided into early infectious events, which involve the infection and integration of the viral DNA into target cell chromosomes; and late events, which involve the expression of viral genes and assembly of infectious virions. To complete the replication cycle, HIV-1 utilizes various cellular pathways.

We identified the Ubc9 E2 SUMO conjugating enzyme as a HIV-1 Gag interaction partner. When this interaction was disrupted in HIV-1 producer cells by Ubc9 siRNA, the virus that was …

Regulation Of Bovine Herpesvirus 1 (Bhv-1) Productive Infection By Cellular Transcription Factors, Aspen M. Workman

School of Biological Sciences: Dissertations, Theses, and Student Research

Bovine herpesvirus 1 (BHV-1) is a significant viral pathogen of cattle responsible for a variety of disease conditions, including: conjunctivitis, pneumonia, genital disorders, abortions, and shipping fever, a serious upper respiratory tract infection. Following acute infection in mucosal epithelium, BHV-1 establishes a lifelong latent infection in sensory ganglionic neurons. During latency, transcription is restricted to the latency related (LR) gene. Elevated corticosteroid levels due to stress and/or immune suppression can initiate reactivation from latency, resulting in virus shedding and spread to susceptible cattle. Additionally, administration of dexamethasone (Dex), a synthetic corticosteroid, to calves latently infected with BHV-1 reproducibly leads to …

Investigation Of Bovine Herpesvirus 1 (Bhv-1) Encoded Infected Cell Protein 0 (Bicp0), Natasha N. Gaudreault

School of Biological Sciences: Dissertations, Theses, and Student Research

Bovine herpesvirus 1 (BHV-1) is a significant pathogen of cattle.  Following acute infection, BHV-1 establishes a latent infection that persists for the life of the infected host.  Stress induced factors cause the virus to reactivate from latency, resulting in virus transmission and transient immune suppression.  BHV-1 encoded bICP0 is expressed early and constitutively throughout productive infection.  bICP0 is critical for efficient viral replication, virulence, and reactivation in cattle because it stimulates viral transcription and interferes with innate immune responses.  bICP0 potentially interacts with a variety of proteins to activate viral gene expression and inhibit innate antiviral defenses.  bICP0 localizes to …

The Molecular Mechanism Of Viral Transactivator Rta-Mediated Kaposi’S Sarcoma-Associated Herpesvirus (Kshv) Lytic Replication, Hui-Ju Wen

School of Biological Sciences: Dissertations, Theses, and Student Research

Kaposi’s sarcoma-associated herpesvirus (KSHV) is a member of the gamma-herpesvirinae subfamily and displays two distinct life phases, latency and lytic replication. Infection with KSHV mostly results in a latent state. A small population of infected cells can spontaneously undergo lytic phase, which is marked by abundant viral gene expression and production of infectious viral progeny. Lytic replication is important for transmission of KSHV in the population and development of diseases. RTA (replication and transcription activator) is a master regulator of KSHV lytic replication. Expression of RTA alone is sufficient to disrupt KSHV latency and initiate the lytic replication cascade. The …

Transcription Analysis Of The Chlorovirus Paramecium Bursaria Chlorella Virus-1, Giane M. Yanai

School of Biological Sciences: Dissertations, Theses, and Student Research

Paramecium bursaria chlorella virus (PBCV-1), a member of the family Phycodnaviridae, is a large dsDNA, plaque-forming virus that infects the unicellular green alga Chlorella NC64A. The 331 kb PBCV-1 genome is predicted to encode 365 proteins and 11 tRNAs. To follow global transcription during PBCV-1 replication, a microarray containing 50-mer probes to the PBCV-1 365 protein-encoding genes (CDS) was constructed. Competitive hybridization experiments were conducted employing cDNAs from poly A-containing RNAs obtained from cells at seven time points after virus infection. The results led to the following conclusions: i) the PBCV-1 replication cycle is temporally programmed and regulated; ii) 360 …