Life Sciences Commons^™

Evaluating A Test For Shedding Propensity Using Tape Lifts From Different Skin Locations, Xiao M. Chen

Student Theses

The shedding propensity of a person can assist data interpretation in casework when assessing the possibility of passive transfer for DNA analysis. Past studies on shedding propensity evaluated palmar skin (washed and unwashed) deposits. This study compared different skin locations with respect to shedding propensity, and explored the potential of tape-lifts as a skin surface collection method. Eight different skin types and samples were collected with adhesive tape disks from 28 participants over three non-consecutive days; the washed and unwashed fingers from both hands, toe, and arm, neck below ear, and nape. Samples were extracted, quantified, amplified, genotyped, and evaluated …

Understanding Snow Leopard (Panthera Uncia) Population Structure, Diet, And Human-Wildlife Dimensions Using Noninvasive Genetic Approaches, Charlotte Hacker

Electronic Theses and Dissertations

Snow leopards (Panthera uncia) are a large cat endemic to the mountains of Central Asia. Despite their status as a flagship species, there are numerous knowledge gaps surrounding their population status, dietary ecology, and relationship with humans. Such knowledge gaps are prohibitive for effective conservation action for the species. Snow leopards are threatened by habitat loss, decreased prey availability, retaliatory killings, and large-scale negative impacts associated with climate change. In order to help bridge these gaps, noninvasive genetic methodologies were deployed in this work across several disciplines. Population genetic metrics were garnered at local, regional, and range-wide scales, …

Retroviral Infection Dynamics In Maine's Wild Turkeys, Stephanie A. Shea

Electronic Theses and Dissertations

Widespread wild turkey reintroductions in the late 1900s have led to increases in population density and geographic distribution across North America. This rapid population expansion has put them into proximity with closely-related wild and domestic avian species, increasing the risks of pathogen transmission. Lymphoproliferative disease virus (LPDV) is an avian oncogenic retrovirus detected in wild turkeys in 2009, and previously known to infect domestic turkeys. Following its initial detection, surveys reported variable LPDV prevalence across eastern North America with most wild turkeys being asymptomatic, however diagnostic cases revealed 10% mortality of LPDV-infected individuals. Given its recent detection, little is known …

Functional Characterization Of Cancer-Associated Dna Polymerase Ε Variants, Stephanie R. Barbari

Theses & Dissertations

Replicative DNA polymerases ε (Polε) and δ (Polδ) achieve high fidelity DNA synthesis through a precise balance of polymerization and exonucleolytic proofreading. Errors that escape proofreading are corrected by DNA mismatch repair (MMR). Ultramutated human cancers with proficient MMR carry alterations in the exonuclease domain of Polε, which were initially predicted to abolish proofreading. However, functional studies in yeast of the most recurrent Polε-P286R variant suggested defects beyond a loss of exonuclease activity. Indeed, biochemical analysis of the yeast Polε-P286R analog revealed increased polymerization capacity in addition to decreased proofreading, which enables efficient mismatch extension and bypass of replication-blocking non-B …

Quantifying Components Of Protein Translation And Metabolite Heterogeneity In Isogenic Microbial Populations, Alexander Schmitz

McKelvey School of Engineering Theses & Dissertations

Cell-to-cell variation in gene expression and metabolite levels have a significant impact on ensemble productivity of microbial bioproduction. New metabolic engineering tools and approaches are needed that consider cell cultures as an amalgam of uniquely behaving individuals to improve the slow commercialization of metabolically engineered systems. Stochastic cellular process including gene expression, metabolism, and growth lead to phenotypic variation between genetically identical cells. Understanding and the ability to control microbial phenotypic variation is key to improving microbial bioproduction metrics. During protein translation, codon usage strongly influences ensemble gene expression but the effect on the variation of gene expression was not …

Developments In Proteomics, Trans-Splicing Technology And Endogenous Transcript Manipulation, Justin Alexander Melendez

Arts & Sciences Electronic Theses and Dissertations

Technological innovation drives scientific discovery, unlocks new avenues of research, and allows us to ask questions in ways that were previously unavailable. With each technological advance, our ability to perturb and explore biological systems has grown in ways previously unimagined. The theme of my thesis is the development of new technologies in biology. To this end, I have worked on three technologies that contribute to the areas of protein sequencing, RNA barcoding for trans-splicing and single-cell applications, and a new method for transcriptional knockdown.

In my first project, digital analysis of proteins by end sequencing (DAPES), we set out to …

Deconvolving Genomic Regulatory Heterogeneity With Self-Reporting Transposons, Arnav Moudgil

Arts & Sciences Electronic Theses and Dissertations

A cell’s identity is a function of the genes expressed in that cell, which are in turn regulated by transcription factors. Over the last decade, single-cell RNA sequencing (RNA-seq) has emerged as a powerful class of techniques to characterize cellular diversity in heterogeneous tissues. These methods barcode transcripts by their cell-of-origin and assign them to specific genes. The resulting high-dimensional data are further processed to reveal clusters of cells sharing transcriptional states. Annotating these clusters, based on either known or discovered marker genes, offers a glimpse into the dynamic composition of an organ or biological process. While single-cell RNA-seq excels …

Structural Variants Are A Major Source Of Gene Expression Differences In Humans And Often Affect Multiple Nearby Genes, Alexandra Jane Scott

Arts & Sciences Electronic Theses and Dissertations

Structural variants (SVs), including copy number variants (CNVs), balanced rearrangements, and mobile element insertions (MEIs), are an important source of diversity in the human genome but their functional effects are not well understood. SVs are technically difficult to detect and genotype1, and mapping is dependent on deep whole genome sequencing (WGS) which was, until recently, unaffordable for large cohorts. For these reasons SVs are not included in most genome-wide studies of functional variants, despite the fact that SVs are known causal agents in multiple clinical disorders2-16. However, recent advancements in high-throughput sequencing technologies that allow for widespread use of WGS, …

Human Plcg2 Haploinsufficiency Results In A Novel Immunodeficiency, Joshua Brandon Alinger

Arts & Sciences Electronic Theses and Dissertations

NK cells are critical for the recognition and lysis of herpesvirus-infected cells. Patients with NK cell immunodeficiency may suffer from unusually severe and/or recurrent herpesvirus infections; however, the genetic cause is frequently unknown. PLCG2 encodes a signaling protein in NK cell and B cell receptor signaling, in which dominant-negative or gain-of-function mutations may cause cold urticaria, antibody deficiency, or autoinflammation. However, loss-of-function mutations and PLCG2 haploinsufficiency have never been reported in human disease. We examined 2 families with autosomal dominant NK cell immunodeficiency with dual high-dimensional techniques, mass cytometry and whole-exome sequencing, to identify the cause of disease. We identified …

Quantitative Characterization Of Microbial Ecologies In Dysbiosis And Infection, Eric Keen

Arts & Sciences Electronic Theses and Dissertations

In 1973, Theodosius Dobzhansky famously wrote that nothing in biology makes sense except in the light of evolution. Today, nearly 50 years later, little in microbiology – or in biology, for that matter – makes sense except in the light of genomics. Microbial genomics populates the field with innumerable testable hypotheses for evaluation in vitro and in vivo, allows us to monitor microbial populations in real time and at a massive scale, and underpins our approach to entire domains of microbiology, including microbial evolution. In this Thesis, I present three studies from my graduate research united by their common theme …

Weedy Rice As A Model System For The Study Of Microevolutionary Interactions In Agricultural Contexts, Marshall Jon Wedger

Arts & Sciences Electronic Theses and Dissertations

Just under one-half of the global population relies on cultivated rice (Oryza sativa) astheir primary source of calories, making the optimization of rice agriculture immensely important. One of the primary constraints to rice agriculture is the de-domesticated (feral) form of rice known as ‘weedy rice’ that aggressively competes for space, soil nutrients, and light. Heavy infestation can reduce crop yields by as much as 80%. As a closely-related weedy descendant of cultivated rice, chemical control is difficult in rice fields, and physical weeding is labor intensive, time consuming, and largely ineffective due to early life-stage mimicry of the crop.

Weedy …

Relationship Of Winter Hair Coat Shedding Ability Of Purebred Angus Dams With Mineral Status, Apparent Forage Digestibility, Uterine Artery Hemodynamics, And Calf Growth And Development, Randy Hunter Burnett

Theses and Dissertations

Winter hair coat shedding ability in southern U.S. cattle production has previously been associated with differences in adjusted birth and weaning weights of calves from dams that shed by June or later (Gray et al., 2011; Cauble et al., 2019). This study was developed to research possible avenues of why these relationships exist with winter hair coat shedding ability. The primary objectives of the following experiments were to: 1) evaluate how mineral status relates to winter hair coat shedding ability, 2) evaluate how winter hair coat shedding ability relates to apparent digestibility of forage, 3) evaluate winter hair coat shedding …

Distribution, Abundance, And Population Genetics Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Mississippi, Luke Pearson

Dissertations

The southeastern United States is a freshwater turtle biodiversity hotspot, second only to southeastern Asia, and this region is inhabited by one of the largest freshwater turtles in the world: the alligator snapping turtle (Macrochelys temminckii). This species was heavily harvested from the 1960’s to the 1980’s for the turtle soup industry, apparently contributing to substantial, range-wide population declines. These declines, coupled with anthropogenic impacts on riverine and floodplain habitats, have led to M. temminckii being petitioned for federal listing under the U.S. Endangered Species Act; it is currently under review by the U.S. Fish and Wildlife Service …

Erecta Family Genes Regulate The Shoot Apical Meristem And Organ Formation, Daniel A. Degennaro

Doctoral Dissertations

Plants are sessile and must adjust their organ growth to their environments. A reservoir of stem cells in the shoot apical meristem (SAM) supplies cells for differentiation into organs. The SAM must balance organ production with stem cell maintenance. The ERECTA family (ERfs) encodes the leucine-rich repeat receptor-like kinases ERECTA (ER), ERECTA-LIKE 1 (ERL1), and ERL2. ERf signaling regulates organ initiation and stem cell maintenance. Results presented in this work include the following:

1) WUSCHEL (WUS) and CLAVATA3 (CLV3) make up a negative feedback loop to maintain SAM size. WUS and CLV3 expression localization is critical for …

The Study Of The Phytopathogen Dickeya Dadantii 3937 Cpx Signaling On The Regulation Of Virulence And Antimicrobial Resistance, Daqing Jiang

Theses and Dissertations

Bacteria respond to environmental cues through a variety of mechanisms. Two-component systems (TCSs) are a conserved mechanism used by bacteria to accurately respond and sense environmental changes. The monitoring of envelope perturbance is linked to TCS CpxA/CpxR in animal-infecting pathogens. The study of the TCS response regulator (RR) CpxR is largely unexplored in phytopathogens. This work focuses on the genetic linkage between cpxR and T3SS expression regulation. We identified the multiple roles of CpxR on several T3SS regulators and its participation in the bacterial second messenger (c-di-GMP) signaling cascade. Moreover, a compound library screening revealed a novel Cpx inducer CHIR-090, …

Divergent Selection For Water Conversion Ratio In Broiler Populations, Joseph Hiltz

Graduate Theses and Dissertations

Water scarcity is a global reality and with the anticipated population growth, freshwater resources will be further strained to meet both human needs and agriculture applications. To ensure a water sustainable and food secure future, all aspects of agriculture must become more efficient. Two strategies were explored. The potential of improving water efficiency in broilers was examined. The first strategy was to develop a more efficient and accurate method for measuring water consumption/inputs in agriculture. To date, water measuring technology has lacked the necessary sophistication to assure accuracy and repeatability of low flow water usage.

After establishing a low flow …

Identification Of Biomarker Systems Of Autism Spectrum Disorder And Uterine Cancer, Allison Hickman

All Dissertations

Complex diseases and disorders pose a challenge to scientists due to their variable and often inconsistent genetic and environmental underpinnings across affected individuals. Because of this variability, large condition-specific datasets and corresponding analytical tools and approaches are being curated as resources to investigate potential genetic trends in complex diseases and disorders. In this Dissertation, I used DNA- and RNA-based resources to discover polygenic biosignatures associated with Autism Spectrum Disorder (ASD) or uterine cancer. To explore the intersection of small-effect common DNA variants and regulation in ASD, I discovered and analyzed trends in allelic associations at eQTLs within ASD-affected individuals. Association …

Using Artificial Intelligence To Decipher Epigenetic Code Of Drug Resistance In The Deadliest Human Malaria Parasite, Samira Jahangiri

USF Tampa Graduate Theses and Dissertations

Malaria remains one of the immense global public health challenges, with an estimated ~200 million cases worldwide in 2019 despite the remarkable gains in reducing this deadly disease over the past decade. The recent emergence and spread of artemisinin resistance (ART-R) in Plasmodium falciparum will increasingly impede global efforts to control and eliminate malaria. Previous studies have observed broad transcriptional changes and identified several noncoding genetic variants strongly associated with ART-R. The broad transcriptional variations suggest that the malaria parasite uses sophisticated epigenetic regulation to survive under drug pressure. Therefore, evaluating the regulatory effects of noncoding-variants in malaria parasites is …

The Evolutionary Origins Of Autism Associated Genes And Their Role In Great Ape Socio-Communicative Behavior, Azeeza Abdulrauf

Master of Science in Integrative Biology Theses

Autism Spectrum Disorder (ASD) is a set of neurological disorders characterized by reduced social interactions and deficits in verbal and nonverbal communication. Although there are no clear genetic markers for ASD, studies have found associations between gene single nucleotide polymorphisms (SNPs) and patients diagnosed with ASD. For this study, the focus is on OXTR, AVPR1A, and FOXP2. OXTR is reported to regulate empathy and stress reactivity while AVPR1A is reported to regulate stress management and territorial aggression, as well as social bonding and recognition. FOXP2 is one of the first genes to be associated with both speech and language recognition …

High Rates Of Polygyny In Tropical Mexico Within The Native Range Of Vespula Squamosa., Alex K. Snyder, Kevin J. Loope

Honors College Theses

Polygyny, or the formation of colonies with multiple cooperating queens, has been observed in a variety of social Hymenoptera and likely exists as a convergent evolutionary strategy. Polygyne cooperation has been observed in several Vespula sp. and is correlated with a perennial social strategy. This perennial-polygyne behavior has been observed most commonly within the tropical and subtropical regions of the invasive Vespula pensylvanica and V. germanica, and rarely within their native temperate ranges. This phenomenon has been relatively undocumented within the tropical portions the V. squamosa native range, despite it being observed in their temperate ranges several times. We observed …

The Multifaceted Role Of Ccar-1 In The Alternative Splicing And Germline Regulation In Caenorhabditis Elegans, Doreen Ikhuva Lugano

USF Tampa Graduate Theses and Dissertations

The Cell Division Cycle and Apoptosis Regulator (CCAR) family members are an enigmatic family of proteins regulating metabolism, cancer, apoptosis, DNA damage, and stress. Mammals have CCAR family members, CCAR1 and CCAR2/DBC1, which evolved from the founding family member CCAR-1/LST-3 expressed in Caenorhabditis elegans. Several studies have shown the importance of understanding these proteins' function in standard and altered physiological processes. Our studies aim to understand the genome-wide alternative splicing and germline regulation of Caenorhabditis elegans CCAR-1 in normal and heat shock conditions. Recently, mammalian CCAR family member CCAR2/DBC1 regulates the alternative splicing by forming a complex with ZNF326. This …

Human 5’-Tailed Mirtrons Are Processed By Rnasep, Mohammad Farid Zia

Dissertations

Approximately a thousand microRNAs (miRNAs) are documented from human cells. A third appear to transit non-canonical pathways that typically bypass processing by Drosha, the dedicated nuclear miRNA producing enzyme. The largest class of non-canonical miRNAs are mirtrons which eschew Drosha to mature through spliceosome activity. While mirtrons are found in several configurations, the vast majority of human mirtron species are 5’-tailed. For these mirtrons, a 3’ splice site defines the 3’ end of their hairpin precursor while a “tail” of variable length separates the 5’ base of the hairpin from the nearest splice site. How this tail is removed is …

Population Genetic Analyses Of Arctic Char (Salvelinus Alpinus) Life History Types In Nettilling Lake & Amadjuak River Ecosystem: A Test Of Reproductive Isolation, Chen Liu

Electronic Theses and Dissertations

A great number of studies have identified strong genetic differences between sympatric anadromous and resident populations of Salmonidae. However, Arctic char (Salvelinus alpinus) migratory phenotypes in the Nettilling Lake and Amadjuak River ecosystem in Nunavut, Canada have not been genetically characterized, and it remains unclear if distinct genotypes and phenotypes associated with migratory life history differences are maintained through reproductive isolation, and they have been assumed to be sympatric populations, or co-occurring populations. Co-occurring Arctic char (n=225) were sampled from eleven sites along the Amadjuak River in 2014 and 2015. Twelve microsatellite loci were used to quantify genetic variation among …

An Enhancement To Cnn Approach With Synthesized Image Data For Disease Subtype Classification, Narider Pal Singh

Electronic Theses and Dissertations

The introduction of genetic testing has profoundly enhanced the prospects of early detection of diseases and techniques to suggest precision medicines. The subtyping of critical diseases has proven to be an essential part of the development of individualized therapies and has led to deeper insights into the heterogeneity of the disease. Studies suggest that variants in particular genes have significant effects on certain types of immune system cells and are also involved in the risk of certain critical illnesses like cancer. By analyzing the genetic sequence of a patient, disease types and subtypes can be predicted. Recent research work has …

Establishment Of A Pesticide Resistance Monitoring Tool For The Two-Spotted Spider Mite, Tetranychus Urticae, Hanna Varonina

Electronic Thesis and Dissertation Repository

Two-spotted spider mite (TSSM), or Tetranychus urticae (Koch), is a major agriculture pest known for its rapid development of resistance to pesticides. The analysis of spider mites’ pesticide resistance demonstrated that resistance patterns and frequencies vary between T. urticae strains collected from different geographic locations and host plants. This research aims at characterization of pesticide resistance patterns in mite populations present in greenhouses in the Southwestern Ontario by identifying genetic and metabolic markers of their pesticide resistance. The establishment of these markers lays the basis for development of a pesticide resistance diagnostic tool that will enable prediction of population resistance …

Global Population Divergence Of A Cosmopolian Desert Plant, Victor Ryan Alfaro

Biology ETDs

Genetic and phenotypic variation can have different patterns within a species if it has populations with contrasting histories. Populations can have discrete differences that are shaped by different evolutionary scenarios, but within each population, range, or region, traits and association with fitness can also be affected by both edaphic and landscape variation. For my dissertation, I surveyed and experimentally analyzed variation and adaptive potential in Sahara mustard (Brassica tournefortii), a desert annual that has endemic, invasive, and agricultural populations in Africa, Asia, and the Americas. Although my multi-trait analysis generated complex results, my findings can be applied to …

Mitonuclear Mismatch Is Associated With Increased Male Frequency, Outcrossing, And Male Sperm Size In Experimentally-Evolved C. Elegans, Brent William Bever

Dissertations and Theses

We provide the first controlled study of how male frequencies and rates of outcrossing evolve in response to mitonuclear mismatch by allowing replicate lineages of C. elegans nematodes containing either mitochondrial or nuclear mutations of electron transport chain (ETC) genes to evolve under three sexual systems: facultatively outcrossing (wildtype), obligately selfing, and obligately outcrossing. In partial support of a tenet of the mitonuclear sex hypothesis, which predicts that outcrossing will be favored in cases of mitonuclear mismatch, we found evolution of increased male frequency in at least one replicate line of all four ETC mutant backgrounds tested--nuclear isp-1, mitochondrial …

Assesment Of Antibiotic Resistant Gene Expression In Clinical Isolates Of Pseudomonas Aeruginosa, Dustin Esmond

Biology Theses

Increasing prevalence of nosocomial infections by antimicrobial resistant pathogens resulting in higher mortality rates and financial burden is of great concern. Pseudomonas aeruginosa represents one of six highly virulent “ESKAPE” pathogens that exhibit considerable intrinsic drug resistance as well as mechanisms for acquiring further resistance. As many of these mechanisms are regulated through gene expression, we sought to identify regulatory strategies and patterns at play in 23 clinical isolates collected from Baku, Azerbaijan and Tyler, Texas, USA. Real-time quantitative polymerase chain reaction was performed on six gene targets implicated in resistance and contrasted with antibiotic phenotypes. We found AmpC cephalosporinase …

Investigation Of Notch Signaling In Cone Fate Specification In Vertebrate Retina, Xueqing Chen

Dissertations, Theses, and Capstone Projects

In the vertebrate retina, cone photoreceptors are crucial for high acuity color vision. Several retinal diseases lead to loss of cones and there is a need to identify the normal developmental genesis of these cells to inform the development of stem cell-based therapies. Cone genesis has previously been shown to be repressed by Notch signaling, however, the mechanism by which Notch signaling controls cone fate determination is still unclear. It has been identified that cone photoreceptors are formed from multipotent retinal progenitor cells (RPCs) that first generate genetically-defined, restricted RPCs with limited mitotic and fate potential to preferentially form cones …

Functional Characterization Of Arogenate Dehydratase Isoforms In Soybean, Ramtin Sirjani

Electronic Thesis and Dissertation Repository

Phenylalanine flux is partitioned between phenylpropanoid and protein synthesis. The mechanisms behind the metabolic channeling of phenylalanine are largely unknown. Arogenate dehydratase (ADT) enzymes, which catalyze the last and rate-limiting step in the synthesis of phenylalanine in plants, have been shown to interact with the isoflavonoid metabolon in the cytosol. Cytosolic phenylalanine, however, can only be synthesized through prephenate dehydratase (PDT) activity. In this study, putative soybean ADTs (GmADTs) were characterized for their ADT and PDT activity. This was done using complementation assays with two different knockout yeast strains, aro8aro9 and pha2, which lack prephenate aminotransferase and PDT activity, …