Biology Commons^™

The Histone Deacetylase Inhibitor, Ms-275, Sensitizes Metastatic Osteosarcoma To Fasl-Induced Cell Death: A Role For C-Flip, Krithi R. Bindal

Dissertations and Theses (Open Access)

The purpose of this study was to determine the effects of the histone deacetylase inhibitor, MS-275, on the Fas signaling pathway and susceptibility of osteosarcoma (OS) to Fas ligand (FasL)-induced cell death. OS metastasizes almost exclusively to the lungs. We have shown that Fas expression in OS cells is inversely correlated with their metastatic potential. Fas⁺ cells are rapidly eliminated when they enter the lungs via interaction with FasL, which is constitutively expressed in the lungs. Fas^- OS cells escape this FasL-induced apoptosis and survive in the lung microenvironment. Moreover, upregulation of Fas in established OS lung metastases …

Increased Geranylgeranylated K-Ras Contributes To Antineoplastic Effects Of Farnesyltransferase Inhibitors., Mandy A. Hall

Dissertations and Theses (Open Access)

The Ras family of small GTPases (N-, H-, and K-Ras) is a group of important signaling mediators. Ras is frequently activated in some cancers, while others maintain low level activity to achieve optimal cell growth. In cells with endogenously low levels of active Ras, increasing Ras signaling through the ERK and p38 MAPK pathways can cause growth arrest or cell death. Ras requires prenylation – the addition of a 15-carbon (farnesyl) or 20-carbon (geranylgeranyl) group – to keep the protein anchored into membranes for effective signaling. N- and K-Ras can be alternatively geranylgeranylated (GG’d) if farnesylation is inhibited but are …

Host Plant Use By Competing Acacia-Ants: Mutualists Monopolize While Parasites Share Hosts, Stefanie Kautz, Daniel J. Ballhorn, Johannes Kroiss, Steffen U. Pauls, Corrie S. Moreau, Sascha Eilmus, Erhard Strohm, Martin Heil

Biology Faculty Publications and Presentations

Protective ant-plant mutualisms that are exploited by non-defending parasitic ants represent prominent model systems for ecology and evolutionary biology. The mutualist Pseudomyrmex ferrugineus is an obligate plant-ant and fully depends on acacias for nesting space and food. The parasite Pseudomyrmex gracilis facultatively nests on acacias and uses host-derived food rewards but also external food sources. Integrative analyses of genetic microsatellite data, cuticular hydrocarbons and behavioral assays showed that an individual acacia might be inhabited by the workers of several P. gracilis queens, whereas one P. ferrugineus colony monopolizes one or more host trees. Despite these differences in social organization, neither …

Social Organization And Decision Making In North American Bison: Implications For Management, Ryan A. Shaw

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Social organization varies widely among herbivores, and the level of social organization in bison is widely debated. I hypothesized that when mother-daughter relationships are allowed to develop, bison form long-term associations. In my study, 25 treatment mothers were selected from a free-ranging herd and kept together with their calves, while 25 control females had their calves forcefully removed. Treatment mothers and offspring had by far the greatest number of associations with a greater percentage of individuals with a half weight index (HWI) > 0.50. The strongest associations (HWI > 0.31) were among treatment mothers and their offspring. Moreover, these associations persisted over …

Caddisfly Larvae (Limnephilidae) As Predators Of Newt (Taricha Granulosa) Eggs: Another Player In The Coevolutionary Arms Race Revolving Around Tetrodotoxin?, Brian G. Gall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Some populations of newts (Taricha granulosa) possess large quantities of the neurotoxin tetrodotoxin (TTX) in their skin and eggs. Many populations of garter snake (Thamnophis sirtalis) are resistant to this toxin and can consume large numbers of newts with no negative effects. Despite the wealth of information acquired on the interaction between newts and their predator, garter snakes, very little research has been conducted on possible interactions between newts and other predators. I conducted a suite of experiments examining for the presence of other predators on newts, specifically focusing on predators of their eggs and larvae. …

Novel Forests Maintain Ecosystem Processes After The Decline Of Native Tree Species, Joseph Mascaro, R. Flint Hughes, Stefan A. Schnitzer

Biological Sciences Faculty Research and Publications

The positive relationship between species diversity (richness and evenness) and critical ecosystem functions, such as productivity, carbon storage, and nutrient cycling, is often used to predict the consequences of extinction. At regional scales, however, plant species richness is mostly increasing rather than decreasing because successful plant species introductions far outnumber extinctions. If these regional increases in richness lead to local increases in diversity, a reasonable prediction is that productivity, carbon storage, and nutrient cycling will increase following invasion, yet this prediction has rarely been tested empirically. We tested this prediction in novel forest communities dominated by introduced species (~90% basal …

Exercise-Induced Neuroprotection In A Hemiparkinsonian 6-Hydroxydopamine Rat Model, Merrill Russen Landers

UNLV Theses, Dissertations, Professional Papers, and Capstones

Outside of finding a cure, one of the preeminent goals of research in Parkinson's disease (PD) is finding a neuroprotective treatment that when applied prior to the onset of the disease will decrease the risk and severity of the subsequent disease. One such treatment that has potential as a neuroprotective agent in PD is exercise. Several studies have found forced exercise to be protective of Parkinson's disease in adult rodent models; however, few of these studies have used a design wherein voluntary exercise was evaluated. Moreover, no study has used a true neuroprotective design in which exercise was applied prior …

Internet Reviews: Understanding Evolution, John Creech

Library Scholarship

Review of the Understanding Evolution website by the University of California Museum of Paleontology and the National Center for Science Education.

Inhibition O F Herpes Simplex Virus-1 By Black Tea Extract, Sadé Diahann Randall

Theses, Dissertations and Culminating Projects

Tea is a highly consumed beverage with numerous health benefits, such as antioxidant and antiviral properties. The compounds within tea that are believed to be associated with these benefits are polyphenols. Black tea polyphenols are known as theaflavins, and in previous studies have exhibited inhibitory effects on influenza and human immunodeficiency virus 1. Herpes simplex virus -1 (HSV-1) is an extremely common virus and has the ability to cause recurrent infections. A vast majority of adults have been exposed to the virus and could be asymptomatic. The purpose of this study was to determine the lowest inhibitory concentration of black …

Variation And Organization In Social Behavior: Infectious Disease And Human Intergroup Conflict And Warfare; And The Organization Of Foraging Behavior In Harvester Ants, Kenneth Letendre

Biology ETDs

Social behavior is an important contributor to the success of widely distributed animal taxa, including such distantly related taxa as humans and ants. There is variation in the features and organization of social systems based on ecological constraints and goals, as these alter the costs and benefits of social behaviors, and select for different optimal behaviors for social groups in different environments. I present two bodies of research: an effort to explain geographic variation in the frequency and intensity of human civil conflict; and an effort to describe and model the foraging behavior of colonies of harvester ants of the …

The Effects Of Precipitation Variability On C4 Photosynthesis, Net Primary Production And Soil Respiration In A Chihuahuan Desert Grassland, Michell L. Thomey

Biology ETDs

Although the Earths climate system has always been inherently variable, the magnitude and rate of anthropogenic climate change is subjecting ecosystems and the populations that they contain to novel environmental conditions. Because water is the most limiting resource, arid-semiarid ecosystems are likely to be highly responsive to future climate variability. The goal of my dissertation is to understand how precipitation variability affects primary productivity and soil respiration in desert grassland ecosystems. Initially, I reviewed the literature to understand how climate change affects net ecosystem exchange (NEE) across the warm deserts of North America (Chapter 2). Next, I examined the effects …

Lymphocyte Evolution And Ontogeny In Non-Eutherian Mammals, Xinxin Wang

Biology ETDs

Based on their different reproductive modes and evolutionary history, extant mammals are divided into three lineages: eutherians, marsupials and monotremes. Marsupials are the closest relatives to eutherians. They are born immune-incompetent. The characteristic that they develop their immune system postnatally makes them unique models to study newborn immune development and maternal immunology. As monotremes comprises the basal lineage of mammals, the study of monotreme immunology will provide unique insights regarding the origin of the mammalian immune system. Unfortunately, compared to our in-depth knowledge of eutherian immunology, especially humans and mice, knowledge of marsupial and monotreme immunology is scarce. The goal …

Influence Of Substrate And Hydraulic Variables On Habitat Preferences Of A Sculptured And An Unsculptured Freshwater Mussel, Daniel Goodding

Biology Theses

Freshwater mussels of the family Unionidae in North America have been in decline for at least the past 150 years. Major causes behind the decline are thought to be related to alteration or loss of habitat. Recent efforts by researchers have focused on understanding habitat associations of mussels so that more effective conservation efforts can be applied. Recent studies have identified variables that limit mussel community distributions. These variables are a combination of substrate and hydraulic variables that are associated with substrate stability. Furthermore, recent studies have suggested mussel studies are most informative at larger spatial scales and at high …

Estrogen Replacement Therapy As A Means To Reduce Risk Of Alzheimer’S Disease, Erika Perez

Whittier Scholars Program

This senior project is a research paper discussing Alzheimer’s disease. The incidence of Alzheimer’s disease (AD) is significantly higher in women compared to men after the age of 80. Higher AD rates may be attributed to changes in estrogen levels around menopause age, and so hormone replacement therapy (HRT), specifically estrogen replacement therapy (ERT) has been considered as a clinical measure to prevent AD. Studies on the beneficial effects of ERT on the brain have yielded inconsistent results. This review aims to assess the possible neuroprotective effects of ERT on preventing or attenuating AD by considering recent literature on the …

Molecular Phylogenetics And Phylogeography Of The American Box Turtles (Terrapene Spp.), Bradley T. Martin

Biology Theses

The classification of the American box turtles (Terrapene spp.) has remained enigmatic to systematists. Previous comprehensive phylogenetic studies have focused primarily on morphology. The goal of this study was to re-assess the classification of Terrapene spp. by obtaining DNA sequence data from a broad geographic range and from all four species and 11 subspecies within the genus. Tissue samples were obtained for all taxa except for T. nelsoni klauberi. DNA was extracted, and the mitochondrial DNA (mtDNA) cytochrome b (Cytb) and nuclear DNA (nucDNA) glyceraldehyde-3-phosphate-dehydrogenase (GAPD) genes were amplified via polymerase chain reaction and sequenced. The sequence data were analyzed …

Using Ecological Niche Modeling To Predict Occurence Of Rare Fish And Unionid Mussels In East Texas, Ashley Dunithan

Biology Theses

Fish and Unionid mussels are important components of aquatic ecosystems and the population decline of these organisms has become a topic of concern. Currently, there are six species of concern and three-state-threatened fish species and six state-threatened Unionid species that occur in east Texas. However, little information is known about the ecology of these species. In this study, I used ecological niche modeling, the software packages Maxent, and eleven abiotic environmental parameters to predict the probability of occurrence of rare fish and mussel species in east Texas. We were unable to model the fish species; however, the models for the …

The Interacting Effects Of Clumped Seed Dispersal And Distance- And Density-Dependent Mortality On Seedling Recruitment Patterns, Noelle G. Beckman, Claudia Neuhauser, Helene C. Muller-Landau

Biology Faculty Publications

1. Seed dispersal and natural enemies both influence spatial patterns of seedlings, which in turn influence future abiotic and biotic interactions, with consequences for plant populations, distributions and diversity. Clumped seed deposition is common, especially for vertebrate-dispersed seeds, and has the potential to significantly affect interactions with density-responsive enemies, yet has received relatively little attention.
2. We used spatially explicit simulation models to examine how different patterns of seed dispersal and natural enemy attack structure seedling spatial patterns. We simulated clumped seed dispersal by combining a two-dimensional Student’s T dispersal kernel for expected seed rain with a negative binomial distribution for seed …

Protein 14-3-3 Eta Is Essential For Normal Meiotic Spindle Assembly In Mouse Eggs, Santanu De, Shawn Davis, Daniel Letwin, Cyrus Mozena, Douglas Kline

Biology Faculty Proceedings, Presentations, Speeches, Lectures

The 14-3-3 proteins constitute a family of conserved, acidic proteins in a variety of organisms, regulating important intracellular events including cell cycle control, apoptosis, signal transduction and embryonic development. However, little is known about the functions of 14-3-3 in mammalian reproduction. There are seven mammalian isoforms of 14-3-3 (beta, gamma, epsilon, eta, zeta, tau/theta and sigma) encoded by different genes. We previously reported accumulation and co-localization of a specific isoform of 14-3-3, namely 14-3-3 eta, in the region of meiotic spindle apparatus in mouse eggs. To determine the role of 14-3-3 eta, we microinjected mouse oocytes with a translation-blocking morpholino …

Growth And Competitive Effects Of Centaurea Stoebe Populations In Response To Simulated Nitrogen Deposition, Wei-Ming He, Daniel Montesinos, Giles C. Thelan, Ragan M. Callaway

Biological Sciences Faculty Publications

Increased resource availability can promote invasion by exotic plants, raising concerns over the potential effects of global increases in the deposition of nitrogen (N). It is poorly understood why increased N favors exotics over natives. Fast growth may be a general trait of good invaders and these species may have exceptional abilities to increase growth rates in response to N deposition. Additionally, invaders commonly displace locals, and thus may have inherently greater competitive abilities. The mean growth response of Centaurea stoebe to two N levels was significantly greater than that of North American (NA) species. Growth responses to N did …

Terrestrial Vertebrate Families On Noah's Ark, Seth J. Beech

Senior Honors Theses

One of the central challenges faced by young-Earth creation researchers who believe the Bible to be the inerrant Word of God is defending the Biblical claim that two of every kind of nephesh animal was saved from the great flood on Noah’s ark. Recently, Answers in Genesis became involved in the design and construction of a full-sized, authentic replica of Noah’s ark. They have endeavored to be as accurate as possible in presenting the number of kinds that would have needed to be on the ark in order to have the diversity in species that we observe today. In order …

Sex Determination, Tony Gamble

Biological Sciences Faculty Research and Publications

Multicellular animals are a diverse lot, with widely varied body plans and lifestyles. One feature they share, however, is a nearly universal reliance on sexual reproduction for species propagation. Humans have long been fascinated by human sex differences and formal theories on how human sex is determined date at least to Aristotle (in De Generatione Animalium, ca. 335 BCE). However, it is only in the past couple of decades that the genetic and molecular programs responsible for generating the two sexes have been understood in any detail. Sex, it turns out, can be established by many very different and …

Assessing The Genotoxicity Of Triclosan In Tadpoles Of The American Bullfrog, Lithobates Catesbeianus., David Emery

Theses and Dissertations

Amphibians are particularly sensitive to environmental degradation and, therefore, serve as effective environmental quality indicators. Research has suggested that amphibian declines are exacerbated by manmade environmental toxicants, especially those found in high concentrations in urban areas. The NIH has pinpointed genotoxicity as a major route of cancer causation, and has since developed stringent testing procedures for potentially hazardous chemicals. One such method, recognized for its simplicity and economy, is the micronucleus assay. A study was conducted assessing the genotoxicity of the widely used antimicrobial agent Triclosan to American Bullfrog tadpoles. Lithobates catesbeianus tadpoles were reared in glass aquaria containing ultra-high …

Analysis Of The Condition-Specific Regulation Of Puf3p Activity And Puf3p-Mediated Translational Repression Of Mrna In Saccharomyces Cerevisiae, Melanie A. Miller

Dissertations

The Puf family of proteins regulates aspects of eukaryotic development such as embryonic development, and memory formation by promoting translational repression and/or degradation of targeted mRNAs in the cytoplasm. Yeast Puf3p regulates mitochondria biogenesis and function by modulating the stabilities of nuclear-transcribed mitochondrial mRNAs in response to different carbon sources. Dextrose simulates rapid Puf3p-mediated degradation of its mRNA targets via decay complex recruitment. Ethanol, galactose, or raffinose promotes stabilization of mRNA targets, as Puf3p-mediated decay activity is severely inhibited or abolished. In this work, I have established that carbon source-induced inhibition of Puf3p activity is not due to decreased transcription …

The Effects Of Invasive Grasses On The Survival And Germination Of Native Forbs, Rachel A. King

Scripps Senior Theses

Invasive species are an increasingly severe conservation problem that can dramatically alter native plant communities. Although ecologists have proposed many mechanisms for the dominance of invasive species, superior competitive ability is one of the longest standing hypotheses. In winter annual plant communities, germination timing affects competition among plants. I hypothesized that grass invasion has changed the costs and benefits of early and late germination, and that species with flexible germination timing would compete better with invasives. Experiments at the Bernard Field Station in Claremont, CA and germinator trials in a controlled environment were used to examine the survivorship and germination …

A Plant Virus Substrate Induces Early Upregulation Of Bmp2 For Rapid Bone Formation, Pongkwan Sitasuwan, L. Andrew Lee, Peng Bo, Erin N. Davis, Yuan Lin, Qian Wang

Faculty Publications

Many nanoscale materials have been developed to investigate the effects on stem cell differentiations via topographical and chemical cues for applications in tissue engineering and regenerative medicine. The use of plant viruses as cell supporting substrates has been of particular interest due to the rapid induction of bone marrow derived mesenchymal stem cells (BMSCs) towards osteogenic cells. In this study, the role of Tobacco mosaic virus (TMV) and its early effects on osteoinduction with particular emphasis on the regulation of bone morphogenetic protein-2 (BMP2) was examined. We observed that the cells on the virus substrate immediately aggregated and formed bone-like …

Initial Trends In The Kentucky Buck Test Program, Robert S. Kelly

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Robert S. Kelly on April 20, 2012.

Traversing Swanton Road, 7th Ed., James A. West

Academic, Government & Associated Organizational Research Resources

Situated at the northwest end of Santa Cruz County and occupying circa 30 square miles of sharply contrasted terrain, the Scott Creek Watershed concentrates within its geomorphological boundaries, at least 10-12% of California's flora, both native and introduced. Paradoxically, the use/abuse that the watershed has sustained over the past 140+ years, has not necessarily diminished the biodiversity and perhaps parallels the naturally disruptive but biologically energizing processes (fire, flooding, landslides and erosion), which have also been historically documented for the area for +60 years. This is an early edition of an extensive document by James A. West. Please visit the …

Migration Distance And Sexual Dichromatism: Cost Of Migration Is Correlated With Reduced Female Coloration In Wood Warblers, Richard K. Simpson

Biology Honors Theses

Avian sexual dichromatism has been observed to be greater at higher latitudes, and one of the long-standing explanations for the underlying evolutionary forces underlying this geographic pattern is the breeding latitude hypothesis, which focuses on changes in male ornamentation and posits that sexual selection for male ornamentation is stronger at higher latitudes. I offer an alterative hypothesis that focuses on how changes in female coloration can drive the evolution of sexual dichromatism. I propose that the costs of migration, including increased predation risk and high energetic costs, negatively select against elaborate plumage coloration, and that the distance a species migrates …

Polyglutamine Toxicity Is Controlled By Prion Composition And Gene Dosage In Yeast, He Gong, Nina V. Romanova, Kim D. Allen, Pavithra Chandramowlishwaran, Kavita Gokhale, Gary P. Newnam, Piotr Miceczkowski, Michael Y. Sherman, Yury O. Chernoff

Publications and Research

Polyglutamine expansion causes diseases in humans and other mammals. One example is Huntington’s disease. Fragments of human huntingtin protein having an expanded polyglutamine stretch form aggregates and cause cytotoxicity in yeast cells bearing endogenous QN-rich proteins in the aggregated (prion) form. Attachment of the proline(P)-rich region targets polyglutamines to the large perinuclear deposit (aggresome). Aggresome formation ameliorates polyglutamine cytotoxicity in cells containing only the prion form of Rnq1 protein. Here we show that expanded polyglutamines both with (poly-QP) or without (poly-Q) a P-rich stretch remain toxic in the presence of the prion form of translation termination (release) factor Sup35 (eRF3). …

Genome-Wide Patterns Of Arabidopsis Gene Expression In Nature, Christina L. Richards, Ulises Rosas, Joshua Banta, Naeha Bhambhra, Michael D. Purugganan

Biology Faculty Publications and Presentations

Organisms in the wild are subject to multiple, fluctuating environmental factors, and it is in complex natural environments that genetic regulatory networks actually function and evolve. We assessed genome-wide gene expression patterns in the wild in two natural accessions of the model plant Arabidopsis thaliana and examined the nature of transcriptional variation throughout its life cycle and gene expression correlations with natural environmental fluctuations. We grew plants in a natural field environment and measured genome-wide time-series gene expression from the plant shoot every three days, spanning the seedling to reproductive stages. We find that 15,352 genes were expressed in the …