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Oxidative Stress In Avian Embyros, Toshi Tsunekage Dec 2015

Oxidative Stress In Avian Embyros, Toshi Tsunekage

Dissertations

Oxidative stress has been implicated in mediating trade-offs in the evolution of life histories. Oxidative stress results from an imbalance in the production of free radicals and an organism’s antioxidant defenses. Higher metabolic rates associated with more rapid growth and shorter development periods may increase oxidative stress and accumulated cellular damage in embryonic tissues. In my dissertation I explored oxidative stress and antioxidant defenses in avian embryos. I measured levels of oxidative stress in tissues of different stage embryos of Japanese quail (Coturnix japonica), and tested if patterns of lipid peroxidation could be explained by changes in the developing embryo’s …


Discovery And Metabolic Engineering Of Steroid Alkaloid Biosynthetic Genes From (Veratrum Californicum), Megan M. Augustin Nov 2015

Discovery And Metabolic Engineering Of Steroid Alkaloid Biosynthetic Genes From (Veratrum Californicum), Megan M. Augustin

Theses

The steroid alkaloid cyclopamine has shown much promise as a treatment for cancers in which aberrant hedgehog signaling plays a role. The compound, originally discovered due to its teratogenic effects in sheep, binds to the hedgehog signaling receptor Smoothend and prevents downstream activation. As this pathway is primarily active during embryonic development, overactivation later in life can lead to tumor formation and proliferation. Several studies have shown that cyclopamine can inhibit and even reverse tumor growth, but limited supply will prevent widespread use upon FDA approval of it or any of its semi-synthetic analogs. As high value plant medicinal compounds …


Ecological Strategies And Disturbance Response Of Tropical Forest Trees: Insight From Functional Trait Variation, Oyomoare Lolade Osazuwa-Peters Nov 2015

Ecological Strategies And Disturbance Response Of Tropical Forest Trees: Insight From Functional Trait Variation, Oyomoare Lolade Osazuwa-Peters

Dissertations

Tropical forests store  40% of terrestrial carbon, process six times as much carbon as is released through fossil fuel use, and are epicenters of biodiversity. Despite all that we know about tropical forests, there remains much to discover about variation in ecological strategies, differences in the way species acquire limited resources through dissimilarities in construction and allocation patterns. We also know little as to how this variation shapes the resilience of tropical tree communities to disturbance. These forests are increasingly threatened by global change stressors, such as anthropogenic land-use and climate change. Recent advances in ecological literature show that …


Relationships Of Haemosporidian Parasites To Populations Of Their Avian Hosts In Eastern North America, Vincenzo Alexander Ellis Nov 2015

Relationships Of Haemosporidian Parasites To Populations Of Their Avian Hosts In Eastern North America, Vincenzo Alexander Ellis

Dissertations

Avian Haemosporida are common, vector-transmitted blood parasites of birds throughout the world. During my dissertation research, I explored how multiple host species respond immunologically to natural infections in the wild (Chapter 1) and to experimental infections in the laboratory (Chapter 2). Despite their tractability as a model host-parasite system and a burgeoning literature on avian Haemosporida, little is known about how their populations interact across large areas (hereafter “regions”). I present data from parasite surveys of birds across eastern North America suggesting that continental parasite populations track host populations across the region, but also that the host breadth of a …


The Role Of Arabidopsis Aminoalcoholphosphotransferase 1 And 2 In Plant Development And Oil Production And Transcriptional Regulation Of Seed Oil Accumulation By Glabra2, Yu Liu Aug 2015

The Role Of Arabidopsis Aminoalcoholphosphotransferase 1 And 2 In Plant Development And Oil Production And Transcriptional Regulation Of Seed Oil Accumulation By Glabra2, Yu Liu

Dissertations

Vegetable oils are important commodities as human foods, animal feeds, renewable industrial feedstocks, and biofuels. Many biochemical and regulation events are involved in seed oil formation, including phospholipids metabolism and transcriptional regulation. In this work, I investigated 1) the role of aminoalcoholphosphotransferases (AAPTs) in phospholipid synthesis and plant development, 2) the effects of AAPTs on seed storage lipid production in Arabidopsis and the emerging oil crop Camelina, and 3) the interaction of the lipid mediator phosphatidic acid (PA) with GLABRA2 (GL2), a negative regulator in seed oil production. AAPTs are the enzymes that produce phosphatidylcholine (PC) and phosphatidylethanolamine (PE). The …


Overexpression Of Patatin‐Related Phospholipase Aiiiδ Altered Plant Growth And Increased Seed Oil Content In Camelina, Xuemin Wang, Maoyin Li, Fang Wei, Amanda Tawfall, Michelle Tang, Allison Saettele Aug 2015

Overexpression Of Patatin‐Related Phospholipase Aiiiδ Altered Plant Growth And Increased Seed Oil Content In Camelina, Xuemin Wang, Maoyin Li, Fang Wei, Amanda Tawfall, Michelle Tang, Allison Saettele

Biology Department Faculty Works

Camelina sativa is a Brassicaceae oilseed species being explored as a biofuel and industrial oil crop. A growing number of studies have indicated that the turnover of phosphatidylcholine plays an important role in the synthesis and modification of triacylglycerols. This study manipulated the expression of a patatin‐related phospholipase AIIIδ (pPLAIIIδ) in camelina to determine its effect on seed oil content and plant growth. Constitutive overexpression of pPLAIIIδ under the control of the constitutive cauliflower mosaic 35S promoter resulted in a significant increase in seed oil content and a decrease in cellulose content. In addition, the content of major membrane phospholipids, …


The Complexity Of Background Clutter Affects Nectar Bat Use Of Flower Odor And Shape Cues, Nathan Muchhala, Diana Serrano Jul 2015

The Complexity Of Background Clutter Affects Nectar Bat Use Of Flower Odor And Shape Cues, Nathan Muchhala, Diana Serrano

Biology Department Faculty Works

Given their small size and high metabolism, nectar bats need to be able to quickly locate flowers during foraging bouts. Chiropterophilous plants depend on these bats for their reproduction, thus they also benefit if their flowers can be easily located, and we would expect that floral traits such as odor and shape have evolved to maximize detection by bats. However, relatively little is known about the importance of different floral cues during foraging bouts. In the present study, we undertook a set of flight cage experiments with two species of nectar bats (Anoura caudifer and A. geoffroyi) and artificial flowers …


Climate-Driven Change In Himalayan Rhododendron Phenology, Robert Evan Hart May 2015

Climate-Driven Change In Himalayan Rhododendron Phenology, Robert Evan Hart

Dissertations

Phenology – the seasonal timing of life-history events – is a critical dimension of natural history. It is also one of the earliest and most noticeable traits by which organisms respond to climate change. However, these responses are complex, and only beginning to be understood, especially in the montane and alpine environments that are among the ecosystems most vulnerable to climate change. Drawing from diverse data sets and employing multiple methodologies, I examined how climate affects phenology in Himalayan Rhododendron spp. Comprehensively monitoring flowering phenology over gradients of season and elevation on Mt. Yulong, China – home to a diverse …


Spatial Ecology, Genetic Diversity And Population Structure Of Armenian Vipers, Montivipera Raddei, In Two Different Landscapes, Jeffery Alan Ettling May 2015

Spatial Ecology, Genetic Diversity And Population Structure Of Armenian Vipers, Montivipera Raddei, In Two Different Landscapes, Jeffery Alan Ettling

Dissertations

In an effort to gain a better understanding of the impact that human-modified landscapes are having on snake populations I studied the spatial ecology, gene diversity and population structure of the Armenian Viper, Montivipera raddei in two different landscapes in Armenia. We first examined the spatial ecology and habitat use of Armenian Vipers in a human-modified landscape with a combination of agricultural fields and overgrazed native steppe habitat. While there were no differences in movement rates for either sex through croplands compared to steppe, we did find that males had larger home ranges during the spring if it included cropland. …


Role Of Aminoalcoholphosphotransferases 1 And 2 In Phospholipid Homeostasis In Arabidopsis, Xuemin Wang, Yu Liu, Geliang Wang May 2015

Role Of Aminoalcoholphosphotransferases 1 And 2 In Phospholipid Homeostasis In Arabidopsis, Xuemin Wang, Yu Liu, Geliang Wang

Biology Department Faculty Works

Aminoalcoholphosphotransferase (AAPT) catalyzes the synthesis of phosphatidylcholine (PC) and phosphotidylethanolamine (PE), which are the most prevalent membrane phospholipids in all eukaryotic cells. Here, we show that suppression of AAPTs results in extensive membrane phospholipid remodeling in Arabidopsis thaliana. Double knockout (KO) mutants that are hemizygous for either aapt1 or aapt2 display impaired pollen and seed development, leading to embryotic lethality of the double KO plants, whereas aapt1 or aapt2 single KO plants show no overt phenotypic alterations. The growth rate and seed yield of AAPT RNA interference (RNAi) plants are greatly reduced. Lipid profiling shows decreased total galactolipid and phospholipid …


Comprehensive Quantification Of Triacylglycerols In Soybean Seeds By Electrospray Ionization Mass Spectrometry With Multiple Neutral Loss Scans, Maoyin Li, Emily Butka, Xuemin Wang May 2015

Comprehensive Quantification Of Triacylglycerols In Soybean Seeds By Electrospray Ionization Mass Spectrometry With Multiple Neutral Loss Scans, Maoyin Li, Emily Butka, Xuemin Wang

Biology Department Faculty Works

Soybean seeds are an important source of vegetable oil and biomaterials. The content of individual triacylglycerol species (TAG) in soybean seeds is difficult to quantify in an accurate and rapid way. The present study establishes an approach to quantify TAG species in soybean seeds utilizing an electrospray ionization tandem mass spectrometry with multiple neutral loss scans. Ten neutral loss scans were performed to detect the fatty acyl chains of TAG, including palmitic (P, 16:0), linolenic (Ln, 18:3), linoleic (L, 18:2), oleic (O, 18:1), stearic (S, 18:0), eicosadienoic (20:2), gadoleic (20:1), arachidic (20:0), erucic (22:1), and behenic (22:0). The abundance of …


Heterogeneous Dynamics In Dna Site Discrimination By The Structurally Homologous Dna-Binding Domains Of Ets-Family Transcription Factors, Gaofei He, Ana Tolic, James Bashkin, Gregory Poon Apr 2015

Heterogeneous Dynamics In Dna Site Discrimination By The Structurally Homologous Dna-Binding Domains Of Ets-Family Transcription Factors, Gaofei He, Ana Tolic, James Bashkin, Gregory Poon

Chemistry & Biochemistry Faculty Works

The ETS family of transcription factors exemplifies current uncertainty in how eukaryotic genetic regulators with overlapping DNA sequence preferences achieve target site specificity. PU.1 and Ets-1 represent archetypes for studying site discrimination by ETS proteins because their DNA-binding domains are the most divergent in sequence, yet they share remarkably superimposable DNA-bound structures. To gain insight into the contrasting thermodynamics and kinetics of DNA recognition by these two proteins, we investigated the structure and dynamics of site discrimination by their DNA-binding domains. Electrophoretic mobilities of complexes formed by the two homologs with circularly permuted binding sites showed significant dynamic differences only …


Comparative Phylogeography And Demographic Histories Of West Indian Birds, Maria Wilhelmina Barbosa De Oliveira Pil Apr 2015

Comparative Phylogeography And Demographic Histories Of West Indian Birds, Maria Wilhelmina Barbosa De Oliveira Pil

Dissertations

My dissertation investigates the demographic history of multiple island populations of several Caribbean bird species through an assessment of contemporary genetic diversity, while inferring relationships between the comparative demography of individual island populations and characteristics of the islands and species. The sizes and distributions of populations vary over time, and episodes of expansion and contraction create characteristic patterns of genetic variation within and among populations. Consequently, contemporary patterns of genetic diversity open a window onto demographic and phylogeographic history. The strength of the study lies in the scale and comprehensiveness of the analysis, encompassing most of the West Indian islands …


Phenotypic Heterogeneity In Metabolic Traits Among Single Cells Of A Rare Bacterial Species In Its Natural Environment Quantified With A Combination Of Flow Cell Sorting And Nanosims, Matthias Zimmermann, Matthias Zimmermann, Stéphanie Escrig, Thomas Hübschmann, Mathias Kirf, Mathias Kirf, Andreas Brand, Andreas Brand, R. Inglis, R. Inglis, Niculina Musat, Susann Müller, Andres Meibom, Andres Meibom, Martin Ackermann, Martin Ackermann, Frank Schreiber, Frank Schreiber Apr 2015

Phenotypic Heterogeneity In Metabolic Traits Among Single Cells Of A Rare Bacterial Species In Its Natural Environment Quantified With A Combination Of Flow Cell Sorting And Nanosims, Matthias Zimmermann, Matthias Zimmermann, Stéphanie Escrig, Thomas Hübschmann, Mathias Kirf, Mathias Kirf, Andreas Brand, Andreas Brand, R. Inglis, R. Inglis, Niculina Musat, Susann Müller, Andres Meibom, Andres Meibom, Martin Ackermann, Martin Ackermann, Frank Schreiber, Frank Schreiber

Biology Department Faculty Works

Populations of genetically identical microorganisms residing in the same environment can display marked variability in their phenotypic traits; this phenomenon is termed phenotypic heterogeneity. The relevance of such heterogeneity in natural habitats is unknown, because phenotypic characterization of a sufficient number of single cells of the same species in complex microbial communities is technically difficult. We report a procedure that allows to measure phenotypic heterogeneity in bacterial populations from natural environments, and use it to analyze N2 and CO2 fixation of single cells of the green sulfur bacterium Chlorobium phaeobacteroides from the meromictic lake Lago di Cadagno. We incubated lake …


Species Interactions Differ In Their Genetic Robustness, Lon Chubiz, Brian Granger, Daniel Segrè, William Harcombe Apr 2015

Species Interactions Differ In Their Genetic Robustness, Lon Chubiz, Brian Granger, Daniel Segrè, William Harcombe

Biology Department Faculty Works

Conflict and cooperation between bacterial species drive the composition and function of microbial communities. Stability of these emergent properties will be influenced by the degree to which species’ interactions are robust to genetic perturbations. We use genome-scale metabolic modeling to computationally analyze the impact of genetic changes when Escherichia coli and Salmonella enterica compete, or cooperate. We systematically knocked out in silico each reaction in the metabolic network of E. coli to construct all 2583 mutant stoichiometric models. Then, using a recently developed multi-scale computational framework, we simulated the growth of each mutant E. coli in the presence of S. …


Parallel And Divergent Evolutionary Solutions For The Optimization Of An Engineered Central Metabolism In Methylobacterium Extorquens Am1, Sean Carroll, Lon Chubiz, Deepa Agashe, Christopher Marx Apr 2015

Parallel And Divergent Evolutionary Solutions For The Optimization Of An Engineered Central Metabolism In Methylobacterium Extorquens Am1, Sean Carroll, Lon Chubiz, Deepa Agashe, Christopher Marx

Biology Department Faculty Works

Bioengineering holds great promise to provide fast and efficient biocatalysts for methanol-based biotechnology, but necessitates proven methods to optimize physiology in engineered strains. Here, we highlight experimental evolution as an effective means for optimizing an engineered Methylobacterium extorquens AM1. Replacement of the native formaldehyde oxidation pathway with a functional analog substantially decreased growth in an engineered Methylobacterium, but growth rapidly recovered after six hundred generations of evolution on methanol. We used whole-genome sequencing to identify the basis of adaptation in eight replicate evolved strains, and examined genomic changes in light of other growth and physiological data. We observed great variety …


Conditional Regulation Of Puf1p, Puf4p, And Puf5p Activity Alters Yhb1 Mrna Stability For A Rapid Response To Toxic Nitric Oxide Stress In Yeast, Joseph Russo, Wendy Olivas Mar 2015

Conditional Regulation Of Puf1p, Puf4p, And Puf5p Activity Alters Yhb1 Mrna Stability For A Rapid Response To Toxic Nitric Oxide Stress In Yeast, Joseph Russo, Wendy Olivas

Biology Department Faculty Works

Puf proteins regulate mRNA degradation and translation through interactions with 3' untranslated regions (UTRs). Such regulation provides an efficient method to rapidly alter protein production during cellular stress. YHB1 encodes the only protein to detoxify nitric oxide in yeast. Here we show that YHB1 mRNA is destabilized by Puf1p, Puf4p, and Puf5p through two overlapping Puf recognition elements (PREs) in the YHB1 3' UTR. Overexpression of any of the three Pufs is sufficient to fully rescue wild-type decay in the absence of other Pufs, and overexpression of Puf4p or Puf5p can enhance the rate of wild-type decay. YHB1 mRNA decay …


Human Gephyrin Is Encompassed Within Giant Functional Noncoding Yin–Yang Sequences, Sharlee Climer, Alan Templeton, Weixiong Zhang Mar 2015

Human Gephyrin Is Encompassed Within Giant Functional Noncoding Yin–Yang Sequences, Sharlee Climer, Alan Templeton, Weixiong Zhang

Computer Science Faculty Works

Gephyrin is a highly conserved gene that is vital for the organization of proteins at inhibitory receptors, molybdenum cofactor biosynthesis and other diverse functions. Its specific function is intricately regulated and its aberrant activities have been observed for a number of human diseases. Here we report a remarkable yin–yang haplotype pattern encompassing gephyrin. Yin–yang haplotypes arise when a stretch of DNA evolves to present two disparate forms that bear differing states for nucleotide variations along their lengths. The gephyrin yin–yang pair consists of 284 divergent nucleotide states and both variants vary drastically from their mutual ancestral haplotype, suggesting rapid evolution. …


Fighting Microbial Drug Resistance: A Primer On The Role Of Evolutionary Biology In Public Health, Gabriel Perron, R. Inglis, Pleuni Pennings, Sarah Cobey Mar 2015

Fighting Microbial Drug Resistance: A Primer On The Role Of Evolutionary Biology In Public Health, Gabriel Perron, R. Inglis, Pleuni Pennings, Sarah Cobey

Biology Department Faculty Works

Although microbes have been evolving resistance to antimicrobials for millennia, the spread of resistance in pathogen populations calls for the development of new drugs and treatment strategies. We propose that successful, long-term resistance management requires a better understanding of how resistance evolves in the first place. This is an opportunity for evolutionary biologists to engage in public health, a collaboration that has substantial precedent. Resistance evolution has been an important tool for developing and testing evolutionary theory, especially theory related to the genetic basis of new traits and constraints on adaptation. The present era is no exception. The articles in …


Galapagos Seabirds' Lice Community: Host Hetero-Specific Interactions And Parasite Evolution, Jose Luis Rivera Jan 2015

Galapagos Seabirds' Lice Community: Host Hetero-Specific Interactions And Parasite Evolution, Jose Luis Rivera

Dissertations

My dissertation focused on understanding the factors behind host-parasite specificity and parasite diversification, using Galapagos seabirds and their ectoparasites as the study system. This system comprised the seabird hosts (magnificent and great frigatebirds, Nazca, blue-footed and red-footed boobies) and nine species of ectoparasitic lice (one Pectinopygus ischnoceran louse species infecting each host, two species of Colpocephalum amblyceran lice, one on each frigatebird species, and two shared amblyceran lice, Eidmanniella albescens found on Nazca and blue-footed boobies and Fregatiella aurifasciata found on the two frigatebirds). Using as focal species Eidmanniella albescens and Fregatiella aurifasciata, which infect multiple hosts, I analyzed how …


The Global Distribution Of Diet Breadth In Insect Herbivores, Robert Marquis, Matthew Forister, Vojtech Novotny, Anna Panorska, Leontine Baje, Yves Basset, Philip Butterill, Lukas Cizek, Phyllis Coley, Francesca Dem, Ivone Diniz, Pavel Drozd, Mark Fox, Andrea Glassmire, Rebecca Hazen, Jan Hrcek, Joshua Jahner, Ondrej Kaman, Tomasz Kozubowski, Thomas Kursar, Owen Lewis, John Lill, Scott Miller, Helena Morais, Masashi Murakami, Herbert Nickel, Nicholas Pardikes, Robert Ricklefs, Michael Singer, Angela Smilanich, John Stireman, Santiago Villamarín-Cortez, Stepan Vodka, Martin Volf, David Wagner, Thomas Walla, George Weiblen, Lee Dyer Jan 2015

The Global Distribution Of Diet Breadth In Insect Herbivores, Robert Marquis, Matthew Forister, Vojtech Novotny, Anna Panorska, Leontine Baje, Yves Basset, Philip Butterill, Lukas Cizek, Phyllis Coley, Francesca Dem, Ivone Diniz, Pavel Drozd, Mark Fox, Andrea Glassmire, Rebecca Hazen, Jan Hrcek, Joshua Jahner, Ondrej Kaman, Tomasz Kozubowski, Thomas Kursar, Owen Lewis, John Lill, Scott Miller, Helena Morais, Masashi Murakami, Herbert Nickel, Nicholas Pardikes, Robert Ricklefs, Michael Singer, Angela Smilanich, John Stireman, Santiago Villamarín-Cortez, Stepan Vodka, Martin Volf, David Wagner, Thomas Walla, George Weiblen, Lee Dyer

Biology Department Faculty Works

Understanding variation in resource specialization is important for progress on issues that include coevolution, community assembly, ecosystem processes, and the latitudinal gradient of species richness. Herbivorous insects are useful models for studying resource specialization, and the interaction between plants and herbivorous insects is one of the most common and consequential ecological associations on the planet. However, uncertainty persists regarding fundamental features of herbivore diet breadth, including its relationship to latitude and plant species richness. Here, we use a global dataset to investigate host range for over 7,500 insect herbivore species covering a wide taxonomic breadth and interacting with more than …


Lineage Sorting In Multihost Parasites: Eidmanniella Albescens And Fregatiella Aurifasciata On Seabirds From The Galapagos Islands, Jose Rivera-Parra, Iris Levin, Kevin Johnson, Patricia Parker Jan 2015

Lineage Sorting In Multihost Parasites: Eidmanniella Albescens And Fregatiella Aurifasciata On Seabirds From The Galapagos Islands, Jose Rivera-Parra, Iris Levin, Kevin Johnson, Patricia Parker

Biology Department Faculty Works

Parasites comprise a significant percentage of the biodiversity of the planet and are useful systems to test evolutionary and ecological hypotheses. In this study, we analyze the effect of host species identity and the immediate local species assemblage within mixed species colonies of nesting seabirds on patterns of genetic clustering within two species of multihost ectoparasitic lice. We use three genetic markers (one mitochondrial, COI, and two nuclear, EF1‐α and wingless) and maximum likelihood phylogenetic trees to test whether (1) parasites show lineage sorting based on their host species; and (2) switching of lineages to the alternate host species depends …


Evolution And Ecology Of Two Iconic Australian Clades: The Meliphagidae (Birds) And The Hakeinae (Plants), Eliot Trimarchi Miller Jan 2015

Evolution And Ecology Of Two Iconic Australian Clades: The Meliphagidae (Birds) And The Hakeinae (Plants), Eliot Trimarchi Miller

Dissertations

The first part of this dissertation explores the evolution of two iconic groups of species through Australian climate space: the Meliphagidae, or honeyeaters, which are primarily nectar-feeding birds, and the Hakeinae, a section of the plant family Proteaceae. Both groups are inferred to have had their origins in Gondwanan rainforests that were widespread across Australia 45 million years ago and then diversified into more arid environments as the continent’s climate became more arid. Accordingly, dry environments are inhabited by closely related (phylogenetically clustered) sets of species, although, in contrast to the honeyeaters, Hakeinae communities are characterized by more localized diversification. …


Stereocontrolled 1,2-Cis Glycosylation As The Driving Force Of Progress In Synthetic Carbohydrate Chemistry, Swati Nigudkar, Alexei Demchenko Jan 2015

Stereocontrolled 1,2-Cis Glycosylation As The Driving Force Of Progress In Synthetic Carbohydrate Chemistry, Swati Nigudkar, Alexei Demchenko

Chemistry & Biochemistry Faculty Works

Recent developments in stereoselective 1,2-cis glycosylation that have emerged during the past decade are surveyed herein. For detailed coverage of the previous achievements in the field the reader is referred to our earlier reviews: A. V. Demchenko, Curr. Org. Chem., 2003, 7, 35–79 and Synlett, 2003, 1225–1240.