Virology Commons^™

Retrotransposon-Mediated Transduction Of An Environmental Cue To Regulate Centrosome Fate, Shawn Patrick Murphy

Legacy Theses & Dissertations (2009 - 2024)

In 1969, the enrichment of mobile element repeat sequences led Britton and Davidson to propose the hypothesis that gene expression in higher eukaryotes is regulated through the exaptation of mobile elements. In this work, I have explored the hypothesis that mobile elements can also be harnessed by the host to regulate asymmetric cell division, thereby determining cell fate. Retrotransposons are ubiquitous eukaryotic mobile elements that transpose through an RNA intermediate. They are often active in cell types that divide asymmetrically to yield daughter cells with different fates, such as embryonic stem cells, germline stem cells, neuronal stem cells and the …

Rna Modifications As A Novel Mediator Of Viral Infection, Rachel Netzband

Legacy Theses & Dissertations (2009 - 2024)

Viral epitranscriptomics is a novel field of RNA biology. Chemical groups are appended to RNA nucleotides under different conditions in cells, and I examine these changes using a mass spectrometry-based approach. Various changes are found to occur in post-transcriptional modifications (PTMs) during viral infection. The field primarily studies a small number of PTMS, such as m6A, while I explore a variety of novel modifications and their impact on viral infection. Hepatitis C virus (HCV) infection induces a variety of modification changes, including the novel presence of dimethylcytosine (m5Cm/m44C). One Writer enzyme for this modification is determined to likely be METTL15, …

Narratives On The Academic Resilience Of Former Homeless Students, Alia Aboulhosn

Walden Dissertations and Doctoral Studies

The number of homeless students in U.S public schools continues to rise. Although many homeless students drop out due to challenges they face, lacking is research on how some homeless students overcome challenges and graduate high school, referred to as academically resilient. The purpose of this qualitative narrative study was to gain a deeper understanding of the experiences that promoted former students who were homeless during their senior year of high school to graduate despite adversity, using Resiliency Theory as the theoretical framework. Semi-structured interviews with five participants provided insight into the broader sociopolitical and personal contexts in their stories, …

The Roles Of The Actin Network And Co-Opted Host Factors In Tbsv Replication, Melissa Gabriela Molho Medina

Theses and Dissertations--Plant Pathology

Positive-stranded (+) RNA viruses are the largest family of viruses that infect plants, causing important economic losses in different crops. Tomato bushy stunt virus (TBSV), a small positive-stranded RNA virus, has emerged as a model virus to study virus-host interactions. TBSV encodes for only five proteins, therefore, to infect the host cell TBSV co-opts selected host components and subverts specific molecular pathways.

Firstly, I performed a proteomic screening using Arabidopsis proteins. I found that TBSV viral replication proteins interact with 88 host proteins, including the ubiquitin-conjugating enzyme 2 (Ubc2), fructose 1,6 biphosphate aldolase (Fba1), and several members of the Hps70 …

Rotavirus A Genome Segments Show Distinct Segregation And Codon Usage Patterns, Irene Hoxie, John J. Dennehy

Publications and Research

Reassortment of the Rotavirus A (RVA) 11-segment dsRNA genome may generate new genome constellations that allow RVA to expand its host range or evade immune responses. Reassortment may also produce phylogenetic incongruities and weakly linked evolutionary histories across the 11 segments, obscuring reassortment-specific epistasis and changes in substitution rates. To determine the co-segregation patterns of RVA segments, we generated time-scaled phylogenetic trees for each of the 11 segments of 789 complete RVA genomes isolated from mammalian hosts and compared the segments’ geodesic distances. We found that segments 4 (VP4) and 9 (VP7) occupied significantly different tree spaces from each other …

Ngs Rna-Seq Reveals Bromovirus Encapsidate Native And Recombinant Viral Rnas, As Well As Cellular Rnas From The Host, Nipin Shrestha

Graduate Research Theses & Dissertations

Brome mosaic virus (BMV), Cowpea chlorotic mottle virus (CCMV), and Broad bean mottle virus (BBMV), the members of the genus Bromovirus, are the experimental model viruses in this dissertation research. Packaging of the RNA genome by the viruses is known to be highly selective and specific for the viral RNA but, not 100% accurate. There is evidence that the viruses specifically or accidentally encapsidate viral RNA variants and host (cellular) RNAs. The scope of this dissertation is to identify different types of RNAs that can be packaged by viruses along with the viral RNAs of parental origin.BMV, CCMV, and BBMV …

Entry And Replication Of Negative-Strand Rna Viruses, Kerri Boggs

Theses and Dissertations--Molecular and Cellular Biochemistry

Hendra virus (HeV) and human metapneumovirus (HMPV) are negative-sense, singled-stranded RNA viruses. The paramyxovirus HeV is classified as a biosafety level 4 pathogen due to its high fatality rate and the lack of a human vaccine or antiviral treatment. HMPV is a widespread pneumovirus that causes respiratory tract infections which are particularly dangerous for young children, immunocompromised individuals, and the elderly. Like HeV, no vaccines or therapies are available to combat HMPV infections. These viruses fuse their lipid envelopes with a cell to initiate infection. Blocking cell entry is a promising approach for antiviral development, and many vaccines are designed …

A Review Of The Molecular Mediators Of Host-Baculovirus Interactions In Lepidoptera, Olivia Crouse

Honors Program Theses

Iowa farmlands occupy approximately 85% of its 35.7 million acres, and Iowa leads the United States in corn and soybean production, with an estimated 2.58 billion and 502 million bushels of corn and soybean produced in 2019, respectively. This successful trend in annual yields has span forty plus years and been consequential to the simultaneous implementation of agricultural- and science-based practices. Genetically modified corn and soybean crop varieties express genes from Bacillus thuringiensis (Bt) which encode insecticidal proteins that protect, with high specificity, against insect pests. While researchers continue to study the molecular mechanism(s) of Bt extensively, alternative environmentally safe …