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Cug Start Codon Generates Thioredoxin/Glutathione Reductase Isoforms In Mouse Testes, Maxim Gerashchenko, Dan Su, Vadim Gladyshev

Department of Biochemistry: Faculty Publications

Mammalian cytosolic and mitochondrial thioredoxin reductases are essential selenocysteine-containing enzymes that control thioredoxin functions. Thioredoxin/glutathione reductase (TGR) is a third member of this enzyme family. It has an additional glutaredoxin domain and shows highest expression in testes. Herein, we found that human and several other mammalian TGR genes lack any AUG codons that could function in translation initiation. Although mouse and rat TGRs have such codons, we detected protein sequences upstream of them by immunoblot assays and direct proteomic analyses. Further gene engineering and expression analyses demonstrated that a CUG codon, located upstream of the sequences previously thought to initiate …

Contributions Of Demography And Dispersal Parameters To The Spatial Spread Of A Stage-Structured Insect Invasion, Tom E. X. Miller, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Stage-structured models that integrate demography and dispersal can be used to identify points in the life cycle with large effects on rates of population spatial spread, information that is vital in the development of containment strategies for invasive species. Current challenges in the application of these tools include: (1) accounting for large uncertainty in model parameters, which may violate assumptions of ‘‘local’’ perturbation metrics such as sensitivities and elasticities, and (2) forecasting not only asymptotic rates of spatial spread, as is usually done, but also transient spatial dynamics in the early stages of invasion. We developed an invasion model for …

Phosphatidylinositol 5-Phosphate Links Dehydration Stress To The Activity Of Arabidopsis Trithorax-Like Factor Atx1, Ivan Ndamukong, David R. Jones, Hanna Lapko, Nullin Divecha, Zoya V. Avramova

School of Biological Sciences: Faculty Publications

Background: Changes in gene expression enable organisms to respond to environmental stress. Levels of cellular lipid second messengers, such as the phosphoinositide PtdIns5P, change in response to a variety of stresses and can modulate the localization, conformation and activity of a number of intracellular proteins. The plant trithorax factor (ATX1) trimethylates the lysine 4 residue of histone H3 (H3K4me3) at gene coding sequences, which positively correlates with gene transcription. Microarray analysis has identified a target gene (WRKY70) that is regulated by both ATX1 and by the exogenous addition of PtdIns5P in Arabidopsis. Interestingly, ATX1 …

Evolution Of The Kdo2-Lipid A Biosynthesis In Bacteria, Stephen O. Opiyo, Rosevelt L. Pardy, Hideaki Moriyama, Etsuko N. Moriyama

School of Biological Sciences: Faculty Publications

Background: Lipid A is the highly immunoreactive endotoxic center of lipopolysaccharide (LPS). It anchors the LPS into the outer membrane of most Gram-negative bacteria. Lipid A can be recognized by animal cells, triggers defense-related responses, and causes Gram-negative sepsis. The biosynthesis of Kdo₂-lipid A, the LPS substructure, involves with nine enzymatic steps.

Results: In order to elucidate the evolutionary pathway of Kdo₂-lipid A biosynthesis, we examined the distribution of genes encoding the nine enzymes across bacteria. We found that not all Gram-negative bacteria have all nine enzymes. Some Gram-negative bacteria have no genes encoding …

Isolation And Characterization Of Bacteria Resistant To Metallic Copper Surfaces, Christophe Espírito Santo, Paula Vasconcelos Morais, Gregor Grass

School of Biological Sciences: Faculty Publications

Metallic copper alloys have recently attracted attention as a new antimicrobial weapon for areas where surface hygiene is paramount. Currently it is not understood on a molecular level how metallic copper kills microbes, but previous studies have demonstrated that a wide variety of bacteria, including Escherichia coli, Staphylococcus aureus, and Clostridium difficile, are inactivated within minutes or a few hours of exposure. In this study, we show that bacteria isolated from copper alloy coins comprise strains that are especially resistant against the toxic properties exerted by dry metallic copper surfaces. The most resistant of 294 isolates were …

Female Field Crickets Incur Increased Parasitism Risk When Near Preferred Song, Cassandra M. Martin, William E. Wagner Jr.

School of Biological Sciences: Faculty Publications

Female animals often prefer males with conspicuous traits because these males provide direct or indirect benefits. Conspicuous male traits, however, can attract predators. This not only increases the risk of predation for conspicuous males but also for the females that prefer them. In the variable field cricket, Gryllus lineaticeps, males that produce preferred song types provide females with greater material benefits, but they are also more likely to attract lethal parasitoid flies. First, we conducted a field experiment that tested the hypothesis that females have a greater risk of fly parasitism when in association with preferred high chirp rate …

Ignoring Population Structure Can Lead To Erroneous Predictions Of Future Population Size, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Predictions of future population size often assume population structures are stable. Are we missing the boat if we ignore the occurrence of unstable or transient dynamics?

Agricultural crops are regularly infested with insect pests whose population size can reach outbreak densities in some years, causing considerable income loss to farmers. In general, the risk of pest outbreaks is highest when insects disperse to crop fields early in the growing season and the population growth rate is high. The population growth rate measures how much the population size (i.e., number of individuals of a species in a defined area) changes per …

Structured Population Dynamics: An Introduction To Integral Modeling, Joseph Briggs, Kathryn Dabbs, Michael Holm, Joan Lubben, Richard Rebarber, Brigitte Tenhumberg, Daniel Riser-Espinoza

School of Biological Sciences: Faculty Publications

In this article we illuminate the differences and similarities between matrix population models and integral population models for single-species stage structured populations. We illustrate the use of integral models with an application to Platte thistle, following Rose et al. [22], showing how the model is determined by basic life history functions. PPMs are ubiquitous in ecology, but for many purposes an IPM might be easier and/or more accurate to use. In TABLE 1 we summarize the similarities between PPMs and IPMs. In order to compare the predictions for PPMs and IPMs, enough data must be available to find the parameters …

Analysis Of Mirna Modifications, Bin Yu, Xuemei Chen

School of Biological Sciences: Faculty Publications

After transcription, a large number of cellular RNAs employ modifications to increase their diversity and functional potential. Modifications can occur on the base, ribose, or both, and are important steps in the maturation of many RNAs. Our lab recently showed that plant microRNAs (miRNAs) possess a 2′-O-methyl group on the ribose of the 3′ terminal nucleotide, and that this methyl group is added after miRNA/miRNA* formation. One function of this modification is to protect miRNAs from 3′ terminal uridylation by an unknown enzymatic activity. It is possible that uridylation of miRNAs triggers their degradation. Here we describe a …

A Signal-Substrate Match In The Substrate-Borne Component Of A Multimodal Courtship Display, Damian O. Elias, Andrew C. Mason, Eileen Hebets

Eileen Hebets Publications

The environment can impose strong limitations on the efficacy of signal transmission. In particular, for vibratory communication, the signaling environment is often extremely heterogeneous at small scales. Nevertheless, natural selection is expected to select for signals well-suited for effective transmission. Here, we test for substrate-dependent signal efficacy in the wolf spider Schizocosa stridulans Stratton 1991. We first explore the transmission characteristics of this important signaling modality by playing recorded substrate-borne signals through three different substrates (leaf litter, pine litter, and red clay) and measuring the propagated signal. We found that the substrate-borne signal of S. stridulans attenuates the least on …

Multimodal Courtship Efficacy Of Schizocosa Retrorsa Wolf Spiders: Implications Of An Additional Signal Modality, Aaron S. Rundus, Roger D. Santer, Eileen Hebets

Eileen Hebets Publications

Here, we simultaneously examine both content and efficacy-based sources of selection on the visual and seismic multimodal courtship display of the wolf spider Schizocosa retrorsa. Immature field-collected S. retrorsa were reared in the laboratory on either high-quantity diet (HD) or low-quantity diet (LD) treatments. On maturation, females of each diet treatment were run in simultaneous mate choice trials with both a HD and an LD male (content-based selection). Simultaneous mate choice trials were conducted across different signaling environments (efficacy-based selection) in a fully crossed 2 × 2 design with visual treatments of light/dark (visual signal present/absent) and seismic treatments …

Mate Choice And Learning, Eileen Hebets, Laura Sullivan-Beckers

Eileen Hebets Publications

While an individual’s genetic framework is a major contributor in determining its eventual mate choice, the role of the environment in further influencing mating decisions has long been recognized. Animals gather information from the environment throughout life, and in some cases, may apply this information to increase their odds of obtaining a high-quality mate. In short, these individuals learn. Moreover, such learning can have a social component. “Social learning” is a general term that describes any learning based on observing, interacting with, and/or imitating others in a social context. Social learning can transmit information vertically, generation to generation (e.g., parent …

Increased Dendrite Branching In Aβpp/Ps1 Mice And Elongation Of Dendrite Arbors By Fasudil Administration, Brian A. Couch, George J. Demarco, Shannon L. Gourley, Anthony J. Koleske

School of Biological Sciences: Faculty Publications

Amyloid-β (Aβ) overproduction and dendrite arbor atrophy are hallmarks of Alzheimer’s disease. The RhoA GTPase (Rho) signals through Rho kinase (ROCK) to control cytoskeletal dynamics and regulate neuron structure. Hyperactive Rho signaling destabilizes neurons leading to dendritic regression that can be rescued by genetic or pharmacological reduction of ROCK signaling. To understand what effect reduced ROCK signaling has on the dendrite arbors of mice that overproduce Aβ, we administered the ROCK inhibitor fasudil to AβPP/PS1 transgenic mice. We report that increased dendrite branching occurs in AβPP/PS1 mice and that fasudil promotes …

Mitochondrial-Nuclear Epistasis Affects Fitness Within Species But Does Not Contribute To Fixed Incompatibilities Between Species Of Drosophila, Kristi L. Montooth, Colin D. Meiklejohn, Dawn N. Abt, David M. Rand

School of Biological Sciences: Faculty Publications

Efficient mitochondrial function requires physical interactions between the proteins encoded by the mitochondrial and nuclear genomes. Co-evolution between these genomes may result in the accumulation of incompatibilities between divergent lineages. We test whether mitochondrialnuclear incompatibilities have accumulated within the Drosophila melanogaster species subgroup by combining divergent mitochondrial and nuclear lineages and quantifying the effects on relative fitness. Precise placement of nine mtDNAs from D. melanogaster, D. simulans and D. mauritiana into two D. melanogaster nuclear genetic backgrounds reveals significant mitochondrial-nuclear epistasis affecting fitness in females. Combining the mitochondrial genomes with three different D. melanogaster X chromosomes reveals significant epistasis …

Synaptic Clustering Of Psd-95 Is Regulated By C-Abl Through Tyrosine Phosphorylation, Karen Perez De Arce, Lorena Varela-Nallar, Olivia Farias, Alejandra Cifuentes, Paulina Bull, Brian A. Couch, Anthony J. Koleske, Nibaldo C. Inestrosa, Alejandra R. Alvarez

School of Biological Sciences: Faculty Publications

The c-Abl tyrosine kinase is present in mouse brain synapses, but its precise synaptic function is unknown. We found that c-Abl levels in the rat hippocampus increase postnatally, with expression peaking at the first postnatal week. In 14 d in vitro hippocampal neuron cultures, c-Abl localizes primarily to the postsynaptic compartment, in which it colocalizes with the postsynaptic scaffold protein postsynaptic density protein-95 (PSD-95) in apposition to presynaptic markers. c-Abl associates with PSD-95, and chemical or genetic inhibition of c-Abl kinase activity reduces PSD-95 tyrosine phosphorylation, leading to reduced PSD-95 clustering and reduced synapses in treated neurons. c-Abl can phosphorylate …

Genetic Conflict And Sex Chromosome Evolution, Colin D. Meiklejohn, Yun Tao

School of Biological Sciences: Faculty Publications

Chromosomal sex determination systems create the opportunity for the evolution of selfish genetic elements that increase the transmission of one sex chromosome at the expense of its homolog. Because such selfish elements on sex chromosomes can reduce fertility and distort the sex ratio of progeny, unlinked suppressors are expected to evolve, bringing different regions of the genome into conflict over the meiotic transmission of the sex chromosomes. Here we argue that recurrent genetic conflict over sex chromosome transmission is an important evolutionary force that has shaped a wide range of seemingly disparate phenomena including the epigenetic regulation of genes expressed …

Compositions And Methods For Controlling Plant Parasitic Nematodes, Harold N. Trick, Judith L. Roe, Timothy C. Todd, Michael A. Herman

School of Biological Sciences: Faculty Publications

The present invention relates to compositions and methods for controlling nematode infestation of plants. In particular, the present invention provides vectors comprising sequences designed to control nematodes by RNA interference (RNAi) and transgenic plants transformed with Such vectors.

Molecular Basis Of A Novel Adaptation To Hypoxic-Hypercapnia In A Strictly Fossorial Mole, Kevin L. Campbell, Jay F. Storz, Anthony V. Signore, Hideaki Moriyama, Kenneth C. Catania, Alexander P. Payson, Joseph Bonaventura, Jörg Stetefeld, Roy E. Weber

Jay F. Storz Publications

Background: Elevated blood O₂ affinity enhances survival at low O₂ pressures, and is perhaps the best known and most broadly accepted evolutionary adjustment of terrestrial vertebrates to environmental hypoxia. This phenotype arises by increasing the intrinsic O₂ affinity of the hemoglobin (Hb) molecule, by decreasing the intracellular concentration of allosteric effectors (e.g., 2,3-diphosphoglycerate; DPG), or by suppressing the sensitivity of Hb to these physiological cofactors.

Results: Here we report that strictly fossorial eastern moles (Scalopus aquaticus) have evolved a low O₂ affinity, DPG-insensitive Hb - contrary to expectations for a mammalian species that is …

Phenotypic Plasticity And Genetic Adaptation To High-Altitude Hypoxia In Vertebrates, Jay F. Storz, Graham R. Scott, Zachary A. Cheviron

Jay F. Storz Publications

High-altitude environments provide ideal testing grounds for investigations of mechanism and process in physiological adaptation. In vertebrates, much of our understanding of the acclimatization response to high-altitude hypoxia derives from studies of animal species that are native to lowland environments. Such studies can indicate whether phenotypic plasticity will generally facilitate or impede adaptation to high altitude. Here, we review general mechanisms of physiological acclimatization and genetic adaptation to high-altitude hypoxia in birds and mammals. We evaluate whether the acclimatization response to environmental hypoxia can be regarded generally as a mechanism of adaptive phenotypic plasticity, or whether it might sometimes represent …

Genetic Differences In Hemoglobin Function Between Highland And Lowland Deer Mice, Jay F. Storz, Amy M. Runck, Hideaki Moriyama, Roy E. Weber, Angela Fago

Jay F. Storz Publications

In high-altitude vertebrates, adaptive changes in blood–O₂ affinity may be mediated by modifications of hemoglobin (Hb) structure that affect intrinsic O₂ affinity and/or responsiveness to allosteric effectors that modulate Hb–O₂ affinity. This mode of genotypic specialization is considered typical of mammalian species that are high-altitude natives. Here we investigated genetically based differences in Hb–O₂ affinity between highland and lowland populations of the deer mouse (Peromyscus maniculatus), a generalist species that has the broadest altitudinal distribution of any North American mammal. The results of a combined genetic and proteomic analysis revealed that deer mice harbor …

Candida Albicans Cellwall Components And Farnesol Stimulate The Expression Of Both Inflammatory And Regulatory Cytokines In The Murine Raw264.7 Macrophage Cell Line, Suman Ghosh, Nina Howe, Katie Volk, Swetha Tati, Kenneth W. Nickerson, Thomas M. Petro

Kenneth Nickerson Papers

Candida albicans causes candidiasis, secretes farnesol, and switches from yeast to hyphae to escape from macrophages after phagocytosis. However, before escape, macrophages may respond to C. albicans’ pathogen-associated molecular patterns (PAMPs) through toll-like receptor 2 (TLR2) and dectin-1 receptors by expressing cytokines involved in adaptive immunity, inflammation, and immune regulation. Therefore, macrophages and the RAW264.7 macrophage line were challenged with C. albicans preparations of live wild-type cells, heat-killed cells, a live mutant defective in hyphae formation, a live mutant producing less farnesol, or an isolate producing farnesoic acid instead of farnesol. Interleukin-6 (IL-6), and IL-1b, IL- 10, and tumor …

No Interaction Between Competition And Herbivory In Limiting Introduced Cirsium Vulgare Rosette Growth And Reproduction, Tomomi  Suwa, Svata M. Louda, F. Leland Russell

Svata M. Louda Publications

Both competition and herbivory have been shown to reduce plant survival, growth, and reproduction. Much less is known about whether competition and herbivory interact in determining plant performance, especially for introduced, weedy plant species in the invaded habitat. We simultaneously evaluated both the main and interactive effects of plant neighbors and insect herbivory on rosette growth and seed reproduction in the year of flowering for Cirsium vulgare (bull thistle, spear thistle), an introduced Eurasian species, in tallgrass prairie in 2 years. Effects of insect herbivory were strong and consistent in both years, causing reduced plant growth and seed production, whereas …

Sirnas Compete With Mirnas For Methylation By Hen1 In Arabidopsis, Bin Yu, Liu Bi, Jixian Zhai, Manu Agarwal, Shengben Li, Qingfa Wu, Shou-Wei Ding, Blake C. Meyers, Hervé Vaucheret, Xuemei Chen

Bin Yu Publications

Plant microRNAs (miRNAs) and small interfering RNAs (siRNAs) bear a 2'-O-methyl group on the 3'-terminal nucleotide. This methyl group is post-synthetically added by the methyltransferase protein HEN1 and protects small RNAs from enzymatic activities that target the 3'-OH. A mutagenesis screen for suppressors of the partial loss-offunction hen1-2 allele in Arabidopsis identified second-site mutations that restore miRNA methylation. These mutations affect two subunits of the DNA-dependent RNA polymerase IV (Pol IV), which is essential for the biogenesis of 24 nt endogenous siRNAs. A mutation in RNA-dependent RNA polymerase 2, another essential gene for the biogenesis of endogenous 24-nt …

Structural Restoration Of Nematodes And Acanthocephalans Fixed In High Percentage Alcohol Using Dess Solution And Rehydration, Soraya Naem, Christopher Pagan, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Ninety-five percent ethanol is the most widely used field and laboratory preservative for nematodes and other helminth specimens intended for use in molecular systematics. Preservation of nematodes in high-concentration alcohols results in structural dehydration artifacts, including shrinkage and body surface distortions sufficient to obscure features required for morphological identification and analysis, thereby compromising precise morphometrics. However, treating dehydrated nematodes using a solution of DMSO, disodium EDTA, and NaCl, followed by rehydration in water produces marked improvements in specimen shape and surface features, resulting from diffusion of water into the tissues and pseudocoelom as the internal salt concentration is reduced. Following …

Soil-Transmitted Helminthiases: Implications Of Climate Change And Human Behavior, Haylee J. Weaver, John M. Hawdon, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Soil-transmitted helminthiases (STHs) collectively cause the highest global burden of parasitic disease after malaria and are most prevalent in the poorest communities, especially in sub-Saharan Africa. Climate change is predicted to alter the physical environment through cumulative impacts of warming and extreme fluctuations in temperature and precipitation, with cascading effects on human health and wellbeing, food security and socioeconomic infrastructure. Understanding how the spectrum of climate change effects will influence STHs is therefore of critical importance to the control of the global burden of human parasitic disease. Realistic progress in the global control of STH in a changing climate requires …

Muellerius Capillaris Dominates The Lungworm Community Of Bighorn Sheep At The National Bison Range, Montana, Vanessa O. Ezenwa, Alicia M. Hines, Elizabeth A. Archie, Eric P. Hoberg, Ingrid M. Asmundsson, John T. Hogg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Lungworm infections are common among bighorn sheep (Ovis canadensis) in North America, and the predominant species reported are Protostrongylus stilesi and P. rushi. The only records of another lungworm species, Muellerius capillaris, infecting bighorns come from South Dakota, USA. At the National Bison Range (NBR), Montana, USA we found that across six sampling periods, 100% of wild bighorn sheep surveyed were passing first-stage dorsal-spined larvae (DSL) which appeared to be consistent with M. capillaris. By contrast, only 39%or fewer sheep were passing Protostrongylus larvae. Using molecular techniques, we positively identified the DSL from the NBR …

Purification Of Parvalbumin From Carp: A Protocol That Avoids Heat Treatment, Stef J. Koppelman, Roland A. Romijn, Harmen H. J. De Jongh, Julie A. Nordlee, Sander Piersma, Martin Hessing, Steve L. Taylor

Department of Food Science and Technology: Faculty Publications

Parvalbumin from carp, a major allergen,was purified to homogeneity using ion exchange chromatography and size exclusion chromatography (estimated purity > 95% to 98% based on SDS-PAGE and native PAGE) with a yield of 318 mg, and a number of basic biochemical characteristics were determined. The identity was confirmed by peptide-mass fingerprinting, and IgE-binding was demonstrated. The UV/Vis absorbance spectra were explained using the previously published amino acid sequences. Far UV-CD spectroscopy was used to confirm the folding character of parvalbumin. We conclude that parvalbumin from carp can be purified on a comparatively large (hundreds of milligrams) scale using a purification protocol …

Vaishno Devi, The Most Famous Goddess Shrine In The Siwāliks, Georgana Foster, Robert Stoddard

Geography Program: Faculty Publications

Vaishno Devi in Jammu has been designated as the "Elder Sister" among the six other Devi shrines in a fairly narrow belt of the Siwāliks between the Yumunii and Chenāb Rivers. During the last few decades Vaishno Devi has become especially important. Pilgrimage to the shrine has increased from 30,000 to almost 7 million since Independence, when the political geography of the region increased accessibility, both physically and perceptually. The growth in the number of visitors can be attributed also to a change in administration of the shrine and to the tremendous increase in religious tourism. Vaishno Devi is now …

New Records Of Bats From The British Virgin Islands, Gary G. Kwiecinski, Jean-Pierre Bacle, Kevel C. Lindsay, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

As currently understood the bat fauna of the British Virgin Islands consists of five species – Noctilio leporinus, Brachyphylla cavernarum, Artibeus jamaicensis, Tadarida brasiliensis , and Molossus molossus. Our knowledge of distribution of bats in the British Virgin Islands is far more limited than that in the United States Virgin Islands. As part of ongoing research on the bats of the Virgin Islands, recent brief surveying periods in the British Virgin Islands have produced new records for some islands. Also, our researching of existing museum collections has discovered unreported new records. Our new data adds information for five species …

Tuberculosis Vaccine, Mohammed A. Sarhan

Saudi Medical Journal

Tuberculosis (TB) is still one of the leading causes of death from a single infectious agent, killing 1.6 million people each year, mostly in developing countries. The existing vaccines, Bacille Calmette and Guerin (BCG), are efficient in preventing the most severe disseminated forms of disease in children and newborns, but its efficacy against active TB in adults has been challenged by several clinical studies. It is a common opinion that only the development of a new and more effective vaccine against TB would significantly ease the deadly disease. In recent years, looking for a new vaccine or an improved TB …