Genetics and Genomics Commons^™

Characterization Of Nodule-Specific, Slac And Mate Membrane Transporters In Medicago Truncatula, Lina Yang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Legumes play a crucial role in sustainable agriculture because of their intrinsic ability to reduce atmospheric N₂ into NH₃ via symbiotic nitrogen fixation (SNF). SNF is carried out in the symbiosome, a quasi-organelle containing endosymbiotic rhizobial bacteria in the cytoplasm of infected cells of the nodule. Therefore, the bacteria are surrounded by a symbiosome membrane (SM), which is derived from the plant plasma membrane during infection. SNF requires constant nutritional exchanges between symbionts, including reduced carbon (dicarboxylates) from the plant for reduced nitrogen (NH₄⁺) from the bacteroids. This exchange of nutrients and signals is fundamental …

Enhancing Water Stress Tolerance In Floriculture Crops, Suejin Park

Graduate Theses, Dissertations, and Problem Reports (ETD)

Water deficit is one of the major constraints on plant growth and development, causing reduction of crop productivity. To minimize water loss, among many adaptation strategies, plants close their stomata to reduce transpiration. The stomatal closure is regulated by light, internal CO2 concentration, and plant hormones, mainly abscisic acid. Plants’ response mechanisms to water deficit are complex processes involving numerous genes and various signaling pathways. Floriculture crops are often exposed to water deficit during shipping and retailing, and these periods often result in damaged crops and profit loss. Understanding of plant responses to water deficit stress will provide us an …

First Record Of White Stork In A Birdstrike In South Africa Above 3,300 M Agl, Desire Dalton, Marli De Bruyn, Monica Mwale, Kim Labuschagne, Melissa Hofmann, Albert Froneman, Hanneline A. Smit-Robinson, Antoinette Kotze

Human–Wildlife Interactions

Birdstrikes to aircrafts are increasing on an annual basis and pose significant aviation safety risks. Identification of the birds involved is key to developing mitigation strategies. Often the only information available to make identifications are feather and/or tissue samples. Relying on feathers alone to identify the bird species requires special expertise and access to museum collections for specimen comparisons. In 2017, feathers and tissue samples were recovered from the engine cowling of an airplane that had just landed at the Oliver Reginald (O. R.) Tambo international airport in South Africa after striking a bird at 3,353 m. To confirm the …

Harnessing Population Genetics For Pest Management: Theory And Application For Urban Rats, Matthew Combs, Kaylee Byers, Chelsea Himsworth, Jason Munshi-South

Human–Wildlife Interactions

Effective management of rodent pests requires an ecological understanding of how they move through their environment and how those movements influence the invasion, persistence, or reinvasion of problematic colonies. Traditional methodologies used to describe rodent movement patterns, such as mark-recapture, are hindered by their time-consuming nature and limited geographic scope. As such, our understanding of how rodents interact with urban environments remains limited. Population genetic principles and tools have the capacity to greatly increase our understanding of rodent population dynamics, ecological relationships, and movements across space, but this field is often unapproachable to non-scientist pest management professionals (PMPs). In this …

Population Health Of Spotted Salamanders (Ambystoma Maculatum) In Created Vernal Pools: An Integrative Approach, Alice R. Millikin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Habitat creation is an important tool for conservation to counteract habitat loss and degradation. Vernal pools are susceptible to destruction due to limited detection, protection, and regulation. These wetlands provide fishless breeding habitat for many amphibian species including spotted salamanders (Ambystoma maculatum) in eastern North America. Determining whether created vernal pool habitat is successful is often determined by demographic data of colonizing populations. I suggest that hormone levels, population genetics, and disease prevalence can improve our understanding of population health in created habitat. The goal of this dissertation was to assess the health of spotted salamander larvae in …

The Impact Of Household Biocides And Antibiotics On Aquatic Microbial Community Composition, Abdulaziz Saud M Alrashdi

Dissertations, Master's Theses and Master's Reports

Triclosan (TCS) is antimicrobial agent that is used in a lot of consumer products, including toothpaste, liquid and bar soap, and cosmetics. TCS has been found in many lakes and rivers in the United States. However, The Food and Drug Administration (FDA) banned TCS recently and it will no longer be used in household products. Despite the recent ban, TCS is known to persist in the environment and may have long-term impacts. We conducted an experiment on using fresh water from three locations Houghton, Green Bay and the Huron Mountains. Our goals in the study is to assess the impact …

Application Of Short Tandem Target Mimic (Sttm) Technique For Functional Analysis Of Micro-Rna396 In Transgenic Poplar Trees, Surattana Boonsai

Dissertations, Master's Theses and Master's Reports

Short Tandem Target Mimic (STTM) is a commonly technique used for functional studies of a number of genes in several plant model systems. However, very little is known about application of STTM technique in tree species. In this study, STTM was applied to knock down microRNA396 (miR396) in transgenic poplar trees for the first time. STTM396 expression resulted in dramatic decrease in miR396 expression levels leading to taller plants with larger leaves and larger leaf cell size. Additionally, an expression analysis of growth regulating factor genes (GRFs) that are members of miR396 target gene family showed up-regulation of GRF07 gene …

Population Structure And Connectivity Of A Groundwater Crustacean Across Northwestern Montana Aquifers, Megan N. Ritter

Master’s Theses

Floodplain aquifer systems are diverse and heterogenous ecosystems that serve many ecological functions, including habitat provision to a range of groundwater species. The Flathead River system of northwestern Montana is home to many floodplain aquifers of great ecological importance to the region. The basic biology, population structure, and dispersal patterns of obligate groundwater organisms that reside within the aquifers of the Flathead are still largely unknown. In this study, we investigate the population structure of one such taxon, an undescribed species of the amphipod genus Stygobromus. For our low-coverage RADseq dataset, we tested the suitability of three different analysis …

Examining The Persistence Of Enviromental Dna In Caves, Abby Guillemette

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

An In Silico Analysis Of Carbapenem-Resistant Klebsiella Pneumoniae, Lauren Elam

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Computational Tools For The Dynamic Categorization And Augmented Utilization Of The Gene Ontology, Eugene Waverly Hinderer Iii

Theses and Dissertations--Molecular and Cellular Biochemistry

Ontologies provide an organization of language, in the form of a network or graph, which is amenable to computational analysis while remaining human-readable. Although they are used in a variety of disciplines, ontologies in the biomedical field, such as Gene Ontology, are of interest for their role in organizing terminology used to describe—among other concepts—the functions, locations, and processes of genes and gene-products. Due to the consistency and level of automation that ontologies provide for such annotations, methods for finding enriched biological terminology from a set of differentially identified genes in a tissue or cell sample have been developed to …

Spatial Genetic Structure And Local Adaptation Within And Among Foxtail Pine (Pinus Balfouriana Subsp. Balfouriana) Populations Located In The Klamath Mountains, California, Rebecca D. Piri

Theses and Dissertations

Foxtail pine (Pinus balfouriana) is a subalpine conifer endemic to California, notably separated into two disjunct subspecies. Previous studies have described the northern subspecies,Pinus balfouriana subsp. balfouriana,as having an uncommonly high level of genetic differentiation and no discernible spatial patterns in phenotypic variation. This study seeks to characterize the spatial genetic structure and patterns of selection of the northern subspecies (Pinus balfouriana subsp. balfouriana) using genome-wide data and to identify the influence of ecology and environment on the unique genetic patterns. I show that genetic differentiation among populations is much less than previously estimated …

Intraspecific Variation In Dehydration Tolerance: Insights From The Tropical Plant Marchantia Inflexa, Rose A. Marks

Theses and Dissertations--Biology

Plants are threatened by global change, increasing variability in weather patterns, and associated abiotic stress. Consequently, there is an urgent need to enhance our ability to predict plant community dynamics, shifts in species distributions, and physiological responses to environmental challenges. By building a fundamental understanding of plant stress tolerance, it may be possibly to protect the ecological services, economic industries, and communities that depend on plants. Dehydration tolerance (DhT) is an important mechanism of water stress tolerance with promising translational applications. Here, I take advantage natural variation in DhT to gain a deeper insight into this complex trait. In addition, …

Multigenerational Genomic And Epigenetic Effects Of Manufactured Silver Nanomaterials In Caenorhabditis Elegans, Anye Wamucho

Theses and Dissertations--Toxicology and Cancer Biology

There has been an increase in the incorporation of silver nanomaterials into consumer products due to their antimicrobial properties. Therefore there is potential for silver nanoparticles (Ag-NPs) to leach out into the environment during different life-cycle stages of these nanomaterial-containing products. Concern about the toxicity of Ag-NPs has led to investigations into their toxic effects on a variety of organisms mainly using acute and sub-chronic, single-generation exposures. The focus of this project was to understand the effects of long-term continuous multigenerational exposure to AgNO₃ and Ag-NPs in both pristine and environmentally transformed forms, on the model organism, Caenorhabditis elegans …

A Poxvirus Pseudokinase Represses Viral Dna Replication Via A Pathway Antagonized By Its Paralog Kinase, Annabel T. Olson, Zhigang Wang, Amber B. Rico, Matthew S. Wiebe

Nebraska Center for Virology: Faculty Publications

Poxviruses employ sophisticated, but incompletely understood, signaling pathways that engage cellular defense mechanisms and simultaneously ensure viral factors are modulated properly. For example, the vaccinia B1 protein kinase plays a vital role in inactivating the cellular antiviral factor BAF, and likely orchestrates other pathways as well. In this study, we utilized experimental evolution of a B1 deletion virus to perform an unbiased search for suppressor mutations and identify novel pathways involving B1. After several passages of the ΔB1 virus we observed a robust increase in viral titer of the adapted virus. Interestingly, our characterization of the adapted viruses reveals that …

Persistent Viral Reservoirs In Lymphoid Tissues In Siv-Infected Rhesus Macaques Of Chinese-Origin On Suppressive Antiretroviral Therapy, Summer Siddiqui, Stefanie Perez, Yong Gao, Lara Doyle-Meyers, Brian T. Foley, Qingsheng Li, Binhua Ling

Nebraska Center for Virology: Faculty Publications

Understanding HIV latent reservoirs in tissues is essential for the development of new strategies targeting these sites for eradication. Here, we assessed the size of latent reservoirs and the source of residual viruses in multiple lymphoid tissues of SIV-infected and fully suppressed rhesus macaques of Chinese-origin (cRMs). Eight cRMs were infected with SIVmac251 and treated with tenofovir and emtricitabine daily for 24 weeks initiated 4 weeks post-infection. Four of the eight animals reached sustained full viral suppression with undetectable viremia. The levels of cell-associated SIV DNA varied in peripheral blood mononuclear cells (PBMCs) and multiple lymphoid tissues, but with higher …

Relationship Between The Cervical Microbiome, Hiv Status, And Precancerous Lesions, Cameron Klein, Daniela Gonzalez, Kandali Samwel, Crispin Kahesa, Julius Mwaiselage, Nirosh Aluthge, Samodha Fernando, John T. West, Charles Wood, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Nearly all cervical cancers are causally associated with human papillomavirus (HPV). The burden of HPV-associated dysplasias in sub-Saharan Africa is influenced by HIV. To investigate the role of the bacterial microbiome in cervical dysplasia, cytobrush samples were collected directly from cervical lesions of 144 Tanzanian women. The V4 hypervariable region of the 16S rRNA gene was amplified and deep sequenced. Alpha diversity metrics (Chao1, PD whole tree, and operational taxonomic unit [OTU] estimates) displayed significantly higher bacterial richness in HIV-positive patients (P = 0.01) than in HIV-negative patients. In HIV-positive patients, there was higher bacterial richness in patients with …

Near-Atomic Structure Of A Giant Virus, Qianglin Fang, Dongjie Zhu, Irina Agarkova, Jagat Adhikari, Thomas Klose, Yue Liu, Zhenguo Chen, Yingyuan Sun, Michael L. Gross, James L. Van Etten, Xinzheng Zhang, Michael G. Rossmann

Nebraska Center for Virology: Faculty Publications

Although the nucleocytoplasmic large DNA viruses (NCLDVs) are one of the largest group of viruses that infect many eukaryotic hosts, the near-atomic resolution structures of these viruses have remained unknown. Here we describe a 3.5 Å resolution icosahedrally averaged capsid structure of Paramecium bursaria chlorella virus 1 (PBCV-1). This structure consists of 5040 copies of the major capsid protein, 60 copies of the penton protein and 1800 minor capsid proteins of which there are 13 different types. The minor capsid proteins form a hexagonal network below the outer capsid shell, stabilizing the capsid by binding neighboring capsomers together. The size …

A Single-Cycle Adenovirus Type 7 Vaccine For Prevention Of Acute Respiratory Disease, Brianna L. Bullard, Brigette N. Corder, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

Adenovirus type 7 (Ad7) infection is associated with acute respiratory disease (ARD), especially in military recruits living in close quarters. Recently, several outbreaks of Ad7 infections have occurred in civilian populations, with some cases leading to death. However, the current Ad7 vaccine is licensed for use only in military recruits because it utilizes an orally delivered wild type virus which is shed in the stool for 28 days after immunization. This poses a safety risk due to the possibility of virus spread to vulnerable populations. To address the need for a safer Ad7 vaccine for use in civilian populations, we …

A Double Humanized Blt-Mice Model Featuring A Stable Human-Like Gut Microbiome And Human Immune System, Lance Daharsh, Jianshui Zhang, Amanda E. Ramer-Tait, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

Humanized mice (hu-mice) that feature a functional human immune system have fundamentally changed the study of human pathogens and disease. They can be used to model diseases that are otherwise difficult or impossible to study in humans or other animal models. The gut microbiome can have a profound impact on human health and disease. However, the murine gut microbiome is very different than the one found in humans. There is a need for improved pre-clinical hu-mice models that have an engrafted human gut microbiome. Therefore, we created double hu-mice that feature both a human immune system and stable human-like gut …

The Vaccinia Virus (Vacv) B1 And Cellular Vrk2 Kinases Promote Vacv Replication Factory Formation Through Phosphorylation-Dependent Inhibition Of Vacv B12, Annabel T. Olson, Zhigang Wang, Annabel Olson, Alexandria C. Linville, Brianna L. Bullard, Eric A. Weaver, Clinton Jones, Matthew S. Wiebe

Nebraska Center for Virology: Faculty Publications

Comparative examination of viral and host protein homologs reveals novel mechanisms governing downstream signaling effectors of both cellular and vi- ral origin. The vaccinia virus B1 protein kinase is involved in promoting multiple facets of the virus life cycle and is a homolog of three conserved cellular enzymes called vaccinia virus-related kinases (VRKs). Recent evidence indicates that B1 and VRK2 mediate a com- mon pathway that is largely uncharacterized but appears independent of previous VRK substrates. Interestingly, separate studies described a novel role for B1 in inhibiting vac- cinia virus protein B12, which otherwise impedes an early event in the …

Ecophysiological Determinants Of Sexual Size Dimorphism: Integrating Growth Trajectories, Environmental Conditions, And Metabolic Rates, Marie-Claire Chelini, John P. Delong, Eileen A. Hebets

Eileen Hebets Publications

Sexual size dimorphism (SSD) often results in dramatic differences in body size between females and males. Despite its ecological importance, little is known about the relationship between developmental, physiological, and energetic mechanisms underlying SSD. We take an integrative approach to understand the relationship between developmental trajectories, metabolism, and environmental conditions resulting in extreme female-biased SSD in the crab spider Mecaphesa celer (Thomisidae). We tested for sexual differences in growth trajectories, as well as in the energetics of growth, hypothesizing that female M. celer have lower metabolic rates than males or higher energy assimilation. We also hypothesized that the environment in …

Contemporary Sexual Selection Does Not Explain Variation In Male Display Traits Among Populations, J. Colton Watts, Allissa Flynn, Brigitte Tenhumberg, Eileen Hebets

Brigitte Tenhumberg Papers

Sexual selection is widely hypothesized to facilitate the evolution of reproductive isolation through divergence in sexual traits and sexual trait preferences among populations. However, direct evidence of divergent sexual selection causing intraspecific trait divergence remains limited. Using the wolf spider Schizocosa crassipes, we characterized patterns of female mate choice within and among geographic locations and related those patterns to geographic variation in male display traits to test whether divergent sexual selection caused by mate choice explains intraspecific trait variation. We found evidence of phenotypic selection on male behavior arising from female mate choice, but no evidence that selection varied …

Weak Warning Signals Can Persist In The Absence Of Gene Flow, J. P. Lawrence, Bibiana Rojas, Antoine Fouquet, Johanna Mappes, Annelise Blanchette, Ralph A. Saporito, Renan Janke Bosque, Elodie A. Courtois, Brice Noonan

Faculty and Student Publications

Aposematic organisms couple conspicuous warning signals with a secondary defense to deter predators from attacking. Novel signals of aposematic prey are expected to be selected against due to positive frequency-dependent selection. How, then, can novel phenotypes persist after they arise, and why do so many aposematic species exhibit intrapopulation signal variability? Using a polytypic poison frog (Dendrobates tinctorius), we explored the forces of selection on variable aposematic signals using 2 phenotypically distinct (white, yellow) populations. Contrary to expectations, local phenotype was not always better protected compared to novel phenotypes in either population; in the white population, the novel phenotype evoked …

Multi-Locus Phylogenetic Inference Of The Howler Monkey (Alouatta) Radiation In South America., Esmeralda Ferreira

Dissertations and Theses

Abstract

Howler monkeys (Alouatta) are the most widely distributed New World primates, ranging from southern Mexico to northern Argentina. They occur in tropical rain forests, flooded and gallery forests, and deciduous and semi-deciduous environments. Despite their importance as seed dispersers, howlers have also been known to be ecological indicators. Available phylogenetic hypotheses for this genus have used chromosomal characters, morphological characteristics, and a limited number of molecular markers and specimens. In spite of these analyses, branching patterns among howler species lineages conflict between studies or remain unresolved. Using 14 unlinked non-coding intergenic nuclear regions under both a concatenated …

Characterizing Chromosomal Aberrations In Cells Deficient For Both Atm And Msh2, Yeliz Inalman

Dissertations and Theses

Ataxia telangiectasia mutated (ATM) and mutS homologue 2 (MSH2) are important DNA repair proteins that participate in DNA repair pathways to maintain genomic integrity. Mice deficient for ATM and MSH2 mice are viable. However, ATM^-/- mice show growth retardation, neurological defects, and spontaneous lymphomagenesis. MSH2^-/- mice suffer from aggressive lymphoid tumors between two to five months of age and have increased microsatellite instability, which predisposes MSH2^-/- mice to carcinomas. However, mice deficient in both ATM and MSH2 are unable to survive beyond postnatal day 21 (P21). The observed lethality in ATM^-/-MSH2^-/- mice may result …

Role Of Moa-1, An Anti-Phosphatase, And Apl-1, An App-Related Protein, In Morphogenesis And Mating Behavior In Caenorhabditis Elegans, Valerie C. Moscoso

Dissertations and Theses

Alzheimer's disease is a neurodegenerative disease that affects more than 30 million people globally. The disease is characterized by an accumulation of extracellular beta-amyloid peptide plaques and intracellular neurofibrillary tangles in the brain. The beta-amyloid peptide is derived from a larger precursor protein, the amyloid precursor protein (APP). Mutations in APP have been correlated with Alzheimer's disease. Due to the presence of two paralogues, APLP1 and APLP2, which have overlapping functions, the normal function of APP is difficult to elucidate. Knockout of the entire APP gene family in mice results in lethality and developmental defects, indicating that the APP gene …

Assay Development For The Identification Of Species And Bioactive Compounds Of Morinda Citrifolia (Noni) In Dietary Supplements By Rt-Qpcr, Dna Sanger Sequencing And Spectroscopy (Uv-Vis/Ftir), Ricardo L. Fernandez Walker

Master's Theses

Regulation standards for dietary supplements lack greatly. Due to this, fraud during the manufacturing of these products might be committed. Previous investigations on herbal dietary supplements have shown that the main ingredient was not present in most of the herbal supplements tested and that these products also contained other substances not stated in the label The purpose of this study was to develop a fluorescent qPCR assay for the identification of Morinda citrifolia herbal species in dietary supplements. Primers for genetic regions rbcL and matK of M. citrifolia were designed. The potential of novel matK primer showed discrimination potential …

Investigating The Prevalence Of An Insecticide Resistance Gene In Culex Mosquito Populations Of Central Illinois, Kylee R. Noel

Masters Theses

The globalization of society has led to the spread of the vectors, mosquitoes, and diseases. Each year millions of people are killed by diseases vectored by mosquitoes. For example, West Nile Virus alone killed over 2,000 people in North America in 2017; 8 of those deaths being in Illinois. Two prominent vectors of West Nile Virus are Culex pipiens and Culex restuans; which are difficult to differentiate based upon morphological features. In this study, mosquitoes collected from two Illinois counties, Coles County and Champaign County, were first identified based upon morphology and this identification was then compared to probe-based …

Impact Of Industrial Biocides On Bacterial Isolates From Hydraulic Fracturing Produced Water, Waad Ahmed Aljohani

Dissertations, Master's Theses and Master's Reports

Biocides are antimicrobial compounds that are designed to kill diverse groups of microbes in an untargeted fashion. Glutaraldehyde and DBNPA are commonly used to manage microbial growth in different industries. It is possible that biocide use may result in the development of bacterial resistance. However, resistance to DBNPA is believed to be limited under normal use conditions. We isolated a number of bacteria from produced water from a hydraulically fractured site in West Texas. We then tested the ability of these isolates to resist Glutaraldehyde and DBNPA. In this study, we found that these isolates have varying resistance to these …