Biology Commons^™

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.

Species Dispersal Modes In Amphitropical Plant Species Of North And South America, Samera Lemma Mulatu

Honors College Theses

Amphitropical disjunct plants are species that occur in both North and South America but not in the intermediate equatorial region. How amphitropical species dispersed across the Americas to their current distribution remains uncertain. To explain amphitropical distributions, three hypotheses were developed to test that (1) species dispersed successively through island hopping across the tropical zone in temperate microhabitats (= stepping stones), (2) species came to their current distribution through vicariance, or (3) species dispersed by a single long distance dispersal event. Twenty-five species were studied to infer their historical distributions with species distribution models in MaxEnt. Distribution models for each …

Upcoming: Coming Spring 2018: Colby On Climate, Colby College

Colby Magazine

No abstract provided.

Science, But Not Fiction: Colby Researchers Consider How "Extreme-Ophiles" Survive And Thrive In The World's Toughest Places, Gerry Boyle

Colby Magazine

"We're exploring how the cell makes the decision to do this," said Assistant Professor of Biology Ron Peck.

A Review Of Plant-Soil Feedbacks And Their Importance For Palouse Prairie Restoration And Management, Rachael Sv Pentico

2020 Symposium Posters

A plant-soil feedback (PSF) is the process in which plants alter both the biotic and abiotic characteristics of the soil they grow in. These changes in the soil composition alter which plants can grow and survive there in the future. Negative PSFs occur when plants struggle to grow in soil that was previously inhabited, due to a buildup of soil pathogens. Positive PSFs, however, provide benefits to the plants due to an abundance of soil microbes, such as AMF. Understanding the effects that PSFs have on plant communities and dynamics could be vital for restoring damaged ecosystems, like the Palouse …

The Effects Of Auditory Predator Cues On Foraging Patterns In Peromyscus Polionotus, Christina L. Sartain

Honors College Theses

Abstract:

While it is established that animals react to predator cues, little research has been done to assess its effect on foraging patterns and behavior. Foraging patterns are determined by a variety of factors associated with perceived predation risk, such as vegetation cover and moonlight exposure. Predator cues come in many forms, both direct and indirect, and are another indicator of perceived predation risk. Past research suggests that oldfield mice, Peromyscus polionotus, may react to indirect cues (i.e vegetation cover) more often than some direct cues, such as urine of a predator. Other indirect cues, such as vegetation cover and …

Generation And Characterization Of A Rack1 Knockout Cell Line, Roy Missall

Seton Hall University Dissertations and Theses (ETDs)

The µ-opioid receptor (MOR) is an important regulator of nociception, bearing the largest role in analgesia of all opioid receptors. This function has made MOR an effective drug-target for the clinical treatment of pain. However, opioid drugs such as morphine and fentanyl are highly addictive, and prolonged abuse can be fatal due to respiratory depression. A key determinant in the cellular and systemic responses to opioids is MOR. At the transcriptional level, MOR is positively regulated by the transcription factors, including poly-C binding protein 1 (PCBP1). Using the two-hybrid screening, PCBP1 was found to interact with receptor for activated C …

Compound Heterozygous Variants In Pediatric Cancers: A Systematic Review, Dustin B. Miller, Stephen R. Piccolo

Faculty Publications

A compound heterozygous (CH) variant is a type of germline variant that occurs when each parent donates one alternate allele and these alleles are located at different loci within the same gene. Pathogenic germline variants have been identified for some pediatric cancer types but in most studies, CH variants are overlooked. Thus, the prevalence of pathogenic CH variants in most pediatric cancer types is unknown. We identified 26 studies (published between 1999 and 2019) that identified a CH variant in at least one pediatric cancer patient. These studies encompass 21 cancer types and have collectively identified 25 different …

Phenotypic Analysis Of S. Aureus Strains From University Student Health Centers And Environmental Controls, Antonio Teixeira

Honors Theses

Methicillin-resistant Staphylococcus aureus (MRSA) is a group of pathogenic bacterial strains resistant to a class of antibiotics that is a major cause for concern in health care systems. There is a lack of study in whether health care centers are reservoirs for these bacteria, especially within developed countries. Five environmental swab samples were collected from five different university health care centers across the region, and 16 swab samples from a general university environment. Any isolated bacterial strains collected underwent five biochemical tests (mannitol fermentation, DNase activity, oxidase activity, catalase activity, and coagulase activity) to preliminarily identify S. aureus bacteria. 24% …

Elucidating The Effects Of Glucose Toxicity On Tauopathy And Aging, Lukas Fluitt

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Diabetes patients are at higher risk of contracting an age-related neurodegenerative disease such as Alzheimer’s disease (AD). However, the mechanisms which link these diseases are poorly understood. We hypothesize that glucose and elevated levels of the glycolysis by product advanced glycation end-products (AGEs), may be involved. AGEs accumulate with age and are elevated in both diabetic and AD patients. Diabetes is a metabolic disorder for which consumption of sugar-rich diets is a major risk factor and is central to etiology in the vast majority of cases.

We show that transgenic C. elegans expressing wild type (WT) human tau fed a …

Determining The Link Between Advanced Glycation Endproducts (Ages), Feeding, And Metabolism, Lauren Wimer

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Reactive a-dicarbonyls (a-DC’s), such as methylglyoxal (MGO), are unavoidable metabolites generated during glycolysis that accumulate with age and have been linked with chronic age-related metabolic diseases such as Diabetes Mellitus. Diabetes Mellitus is generally characterized by peripheral neuropathy and sustained hyperglycemia. Chronic hyperglycemia leads to an increase in glycolysis and a downstream increase in reactive a-DC’s. The human body has a natural method of detoxifying these a-DC’s. Glycolytic cells have enzymes which can detoxify a-DC’s, but if overwhelmed, a-DC’s can accumulate and react non-enzymatically with proteins, lipids and DNA to yield a group of molecules called advanced glycation end-products (AGEs). …

Tympanal Asymmetry In A Parasitoid Fly: Small Asymmetries Produce Big Gains, Max Mikel-Stites, Anne E. Staples

Biology and Medicine Through Mathematics Conference

No abstract provided.

Pvt1 Exon 9 A Regulator Of Claudin Expression In Triple Negative Breast Cancer, Fayola Levine

Theses and Dissertations

Claudin low triple negative breast cancer (TNBC) has the worst clinical outcomes in comparison to other breast cancer subtypes. The underlying molecular mechanisms associated with the aberrant expression of claudins are not well understood. The transcript from PVT1 exon 9 is a regulator of claudin expression, and migration, in TNBC.

Cytotoxic Analysis Of Old Drugs: New Drugs For Alzheimer’S Disease, Sebastian Yumiseba

Theses and Dissertations

Microglia are the resident immune cells of the CNS and constitute about 10% of all cells in the CNS. They have a vital role in Alzheimer’s pathogenesis as either cytotoxic or neuroprotective. Recent efforts are being put into repurposing drugs to target the microglia to treat Alzheimer’s disease.

Developing Tools For Identifying Tissue-Specific Epigenetic Marks And Predicting Dna Hydroxy/Methylation, Yu He

Arts & Sciences Graduate Student Theses and Dissertations

A single genome can derive phenotypically unique cell types through various epigenetic modifications that instruct specific gene expression patterns. Histone modifications, DNA methylation, and DNA hydroxymetylation are the most common epigenetic modifications. To understand the mechanisms how these epigenetic modifications regulate gene expression, one often needs to map these marks genome-wide through profiling methods. Firstly, for histone modifications, Roadmap Epigenomics Consortium generated The Human Reference Epigenome Map, containing thousands of genome-wide histone modification datasets that describe epigenomes of a variety of different human tissue and cell types. This map has allowed investigators to obtain a much deeper and more comprehensive …

Fgf18 In Postnatal Lung Development, Andrew Hagan

Arts & Sciences Graduate Student Theses and Dissertations

The lung is a respiratory organ capable of facilitating gas exchange between external atmospheric O2 and internal CO2 in the bloodstream, necessary to oxygenate tissues. Alveoli, small balloon shaped structures at the distal end of the respiratory tree, are the meeting point between air and blood where gas exchange occurs through simple diffusion. Generation of functionally mature alveoli occurs during alveologenesis, the final postnatal stage of lung development in mice. During alveologenesis the surface area of the lung increases through formation of septal ridges (septation) which are extracellular matrix rich invaginations of the nascent alveolar wall that subdivide the alveoli. …

The Enzymatic Function Of The Tir Domain: From Axon Degeneration To Innate Immunity, Kow Essuman

Arts & Sciences Graduate Student Theses and Dissertations

The Toll/Interleukin-1 Receptor (TIR) domain is an evolutionarily ancient protein domain conserved from bacteria to eukaryotes, and is an essential signaling component of innate immunity pathways. In animal innate immunity, TIR domains have primarily been described for their scaffolding function in assembling protein complexes in host defense. In plant immunity, TIR domains are key components of the intracellular Nucleotide Binding Leucine rich repeat (NLR) immune receptors that confer resistance to pathogens. These NLR receptors trigger cell death and an immune response upon activation, but their mechanism has remained elusive. In bacteria, TIR domain proteins have been suggested to function as …

Epigenetic Dynamics In Normal And Disease Models, Hyo Sik Jang

Arts & Sciences Graduate Student Theses and Dissertations

Deciphering how epigenetic factors, such as DNA methylation and chromatin accessibility, shape normal development and disease progression has been an outstanding goal in developmental biology. Here, I present multiple branches of my thesis to elucidate the epigenetic controls that direct aging in brain, regulate cell fate decision of zebrafish iridophore in pigment differentiation, and dysregulate transposable elements (TEs) in cancer. The first branch focuses on benchmarking a computational statistic tool to characterize DNA methylation dynamics of aging in mouse prefrontal cortex by combining WGBS and TAB-seq to dissect the contribution of CpG methylation and hydroxymethylation. For the second branch, we …

Understanding The Molecular Pathogenesis Of Retinal Neurodegeneration, Jonathan B. Lin

Arts & Sciences Graduate Student Theses and Dissertations

Retinal degenerative diseases are a major cause of morbidity in modern society because visual impairment significantly decreases the quality of life of patients. A significant challenge in treating retinal degenerative diseases is their genetic and phenotypic heterogeneity. Furthermore, limitations in our understanding of disease pathophysiology have led to reliance on therapies that often treat disease endpoints rather than addressing disease etiology and/or pathophysiology. The long-term goal of my thesis research was to provide molecular and cellular insights into the pathophysiology underlying diverse retinal degenerative diseases, which may lead to much-needed, novel therapeutic approaches. During the first part of my thesis …

Epigenetic And Signaling Pathways Regulating The Maintenance Of Cd8 T Cell Identity And Function, Daniel Verbaro

Arts & Sciences Graduate Student Theses and Dissertations

In response to infection, antigen specific CD4 and CD8 T cells rapidly divide to provide help to the immune system and promote cytotoxicity of infected cells, respectively. Through this rapid division, CD4 and CD8 T cells maintain silencing of the opposing lineage’s genes, which is essential to acutely eliminating pathogens. However, not all pathogens are acutely eliminated even when silencing is maintained, and the pathogen persists in the presence of activated CD8 T cells. CD8 T cells chronically exposed to antigen are phenotypically different than CD8 T cells acutely exposed to antigen, but CD8 T cell still exert control over …

Outstanding Questions In Flower Metabolism, Monica Borghi, Alisdair R. Fernie

Biology Faculty Publications

The great diversity of flowers, their color, odor, taste, and shape, is mostly a result of the metabolic processes that occur in this reproductive organ when the flower and its tissues develop, grow, and finally die. Some of these metabolites serve to advertise flowers to animal pollinators, other confer protection towards abiotic stresses, and a large proportion of the molecules of the central metabolic pathways have bioenergetic and signaling functions that support growth and the transition to fruits and seeds. Although recent studies have advanced our general understanding of flower metabolism, several questions still await an answer. Here, we have …

Structural Mechanism Of Poxvirus Sabotage Of T-Cell Costimulation, Jabari Issa Elliott

Arts & Sciences Graduate Student Theses and Dissertations

Poxviruses are characterized by large double stranded DNA genomes that encode numerous proteins tailored for host immune response evasion. Our lab has been investigating a sequence-diverse family of secreted poxvirus proteins that appear to share a conserved beta-sandwich fold, but differ in their immunomodulatory functions. We have termed members of this superfamily Poxvirus Immune Evasion (PIE) proteins, and there appears to be at least 20 distinct subfamilies. As it turns out, cowpox virus (CPXV) encodes 10 PIE proteins, one of which, M2, can inhibit murine T cell activation through specific interactions with co-stimulatory ligands B7. 1 (CD80) and B7. 2 …

Notch-Mediated Regulation Of Atrial Arrhythmogenesis, Catherine Lipovsky

Arts & Sciences Graduate Student Theses and Dissertations

Abnormalities in electrical impulse generation and/or propagation that affect the heartճ normal rhythm are extremely common. Clinically, cardiac arrhythmias are prevalent worldwide, yet the molecular mechanisms underlying their pathology remain largely unknown. Current treatments for arrhythmias primarily target symptoms rather than the underlying cause and these treatments have limited efficacy. The most common risk factor for developing an arrhythmia is a previous cardiac injury; however, the mechanisms underlying this are not well described. My thesis work has demonstrated that the Notch signaling pathway, which is crucial for cardiac patterning and development and is normally quiescent in adult cardiomyocytes (CMs), is …

Metabolic Requirements Of Nk Cell Responses To Viral Infection, Annelise Yoo Mah-Som

Arts & Sciences Graduate Student Theses and Dissertations

In recent years, the field of immunometabolism – the study of how specific changes in cellular metabolism regulate the function of diverse immune cell types—has grown exponentially. Several in vitro studies have examined the metabolic regulation of natural killer (NK) cells, which are first responders for viral infection and malignant transformation; however, much less is known regarding the role of metabolism in directing NK cell responses in vivo, such as during viral infection. In order to examine how NK cell antiviral function is regulated in vivo, we used a wellcharacterized infection with murine cytomegalovirus (MCMV) to assess NK cell cytokine …

Life Of Tau: Oligomerization, Cns Extracellular Clearance And Role As Plasma Biomarker, Tirth Patel

Arts & Sciences Graduate Student Theses and Dissertations

The microtubule associated protein tau (MAPT, commonly referred to as tau) is an intrinsically disordered, highly soluble protein predominantly expressed in axons where it binds and stabilizes microtubules. Under normal physiological conditions, soluble monomeric tau is released in the extracellular space in the interstitial fluid (ISF) by neurons. Additionally it undergoes reversible phosphorylation and other extensive modifications inside the cell under the action of a host of enzymes. However in the disease process tau loses this solubility, detaches from microtubules and ultimately migrates to the somatodendritic compartment of the neuron, where it ultimately forms insoluble fibrillar aggregates known as tau …

Pathophysiology And Treatment Of Murine Globoid Cell Leukodystrophy, Yedda Li

Arts & Sciences Graduate Student Theses and Dissertations

Infantile globoid cell leukodystrophy (GLD, Krabbe disease) is a rapidly progressing, invariably fatal pediatric disorder first described in 1916. Krabbe disease is caused by a deficiency in the lysosomal enzyme, galactosylceramidase (GALC), and is characterized clinically by failure to thrive, limb stiffness, seizures, developmental regression, and death by 2-4 years of age. Galactosylceramidase degrades the cytotoxic glycolipid, galactosylsphingosine (psychosine). In the absence of GALC activity, psychosine accumulates primarily in oligodendrocytes and Schwann cells, resulting in profound demyelination. In 1972, psychosine was hypothesized to be responsible for the clinical signs associated with Krabbe disease. However, the ‘Psychosine Hypothesis’ has never been …

Molecular Insights Into Microbial Adhesion, Roger Davies Klein

Arts & Sciences Graduate Student Theses and Dissertations

Antibiotic-resistant bacterial infections are a serious and immediate threat to global public health. In the United States alone, over 2 million individuals develop antibiotic-resistant infections annually, resulting in 23,000 deaths and $20 billion in excess health care costs. Virulence factors that allow bacteria to invade and persist within the host are promising targets for novel antimicrobial agents that could be used to curb the spread of antibiotic resistance. Development of therapeutics that can selectively eliminate pathogenic bacteria while sparing the beneficial host microbiota requires a detailed molecular understanding of critical virulence factors that facilitate interactions between pathogens and their environments. …

Investigating The Role Of Genetic Variants And Environmental Factors In The Trajectory Of Substance Use Disorders, Linda Johnson

Arts & Sciences Graduate Student Theses and Dissertations

Substance use disorders are a serious threat to public health with devastating social, economic, and health impacts on affected individuals and their families. This dissertation aims to improve understanding of substance use disorders in three parts: first, an epidemiological project examining smoking cessation and e-cigarette use at a population level; second, a genetic project examining the role of genetic variants on tobacco, alcohol, cannabis, and cocaine use; and finally, a review of the utility of polygenic risk scores in predicting risk of substance use behaviors. Cigarette smoking is a leading cause of preventable death, accounting for over 480,000 deaths in …

Effects Of Toxoplasma Gondii Infection On Nk Cells And Ilc1s, Eugene Park

Arts & Sciences Graduate Student Theses and Dissertations

Natural killer cells and Type I innate lymphoid cells (ILCs) are subsets of ILCs. In C57BL/6 mice, they share expression of the surface markers NK1. 1 and NKp46, and can produce the cytokine interferon-gamma. These similarities led to the initial classification of natural killer cells and Type I ILCs together under the category of Group 1 ILCs. However, more recent studies found that natural killer cells and ILC1s develop from distinct progenitor cells and utilize transcription factor in distinct manners. Whereas ILC1s require Tbet for their development and are Eomes-independent, natural killer cells require Tbet only for terminal maturation and …

Signaling Mechanisms In Adaptive Immunity, Saravanan Raju

Arts & Sciences Graduate Student Theses and Dissertations

The adaptive immune response consists of interplay between CD4 T cells, CD8 T cells, and B cells which function in control of pathogen in the host. T cells responding via their TCR express cytokines and costimulatory molecules that support direct effector activity and also promote high-affinity antibody generation through augmenting of B cell responses. However, the molecular components that contribute T cell function to balance viral control and the potential for host damage are incompletely understood. In this work, we establish a role for the adaptor molecule CD2AP in modulation of CD4 T cell responses to chronic LCMV infection in …