Life Sciences Commons^™

Tlr-Trif Pathway Enhances The Expression Of Kshv Replication And Transcription Activator, Florencia Meyer, Erica Ehlers, Andrew Steadman, Thomas Waterbury, Mingxia Cao, Luwen Zhang

School of Biological Sciences: Faculty Publications

Background: Host innate immunity is against virus infection and replication.

Results: Toll-like receptor 3 activation leads to enhanced expression of a key Kaposi’s sarcoma-associated herpesvirus (KSHV) protein.

Conclusion: KSHV uses host Toll-like receptor pathway to augment its critical gene expression. Significance: A virus may usurp host innate immunity for its own benefits.

Widespread Selection Across Coding And Noncoding Dna In The Pea Aphid Genome, Ryan D. Bickel, Joseph P. Dunham, Jennifer A. Brisson

School of Biological Sciences: Faculty Publications

Genome-wide patterns of diversity and selection are critical measures for understanding how evolution has shaped the genome. Yet, these population genomic estimates are available for only a limited number of model organisms. Here we focus on the population genomics of the pea aphid (Acyrthosiphon pisum). The pea aphid is an emerging model system that exhibits a range of intriguing biological traits not present in classic model systems. We performed low-coverage genome resequencing of 21 clonal pea aphid lines collected from alfalfa host plants in North America to characterize genome-wide patterns of diversity and selection. We observed an excess …

Four Distinct Types Of Dehydration Stress Memory Genes In Arabidopsis Thaliana, Yong Ding, Ning Liu, Laetitia Virlouvet, Jean-Jack Riethoven, Michael E. Fromm, Zoya Avramova

School of Biological Sciences: Faculty Publications

Background: How plants respond to dehydration stress has been extensively researched. However, how plants respond to multiple consecutive stresses is virtually unknown. Pre-exposure to various abiotic stresses (including dehydration) may alter plants’ subsequent responses by improving resistance to future exposures. These observations have led to the concept of ‘stress memory’ implying that during subsequent exposures plants provide responses that are different from those during their first encounter with the stress. Genes that provide altered responses in a subsequent stress define the ‘memory genes’ category; genes responding similarly to each stress form the ‘non-memory’ category.

Results: Using a genome-wide …

Regional Contingencies In The Relationship Between Aboveground Biomass And Litter In The World’S Grasslands, Lydia R. O’Halloran, Elizabeth T. Borer, Eric W. Seabloom, Andrew S. Macdougall, Elsa E. Cleland, Rebecca L. Mcculley, Sarah Hobbie, W. Stanley Harpole, Nicole M. Decrappeo, Chengjin Chu, Jonathan D. Bakker, Kendi F. Davies, Guozhen Du, Jennifer Firn, Nicole Hagenah, Kirsten S. Hofmockel, Johannes Knops, Wei Li, Brett A. Melbourne, John W. Morgan, John L. Orrock, Suzanne M. Prober, Carly J. Stevens

School of Biological Sciences: Faculty Publications

Based on regional-scale studies, aboveground production and litter decomposition are thought to positively covary, because they are driven by shared biotic and climatic factors. Until now we have been unable to test whether production and decomposition are generally coupled across climatically dissimilar regions, because we lacked replicated data collected within a single vegetation type across multiple regions, obfuscating the drivers and generality of the association between production and decomposition. Furthermore, our understanding of the relationships between production and decomposition rests heavily on separate meta-analyses of each response, because no studies have simultaneously measured production and the accumulation or decomposition of …

Cd20 Antibody Primes B Lymphocytes For Type I Interferon Production, Dongsheng Xu, Andrew Staedman, Luwen Zhang

School of Biological Sciences: Faculty Publications

CD20 is a B cell surface marker that is expressed in various stages in B lymphocytes and certain lymphomas. Clinical administration of CD20 antibody, such as rituximab, is used widely to treat human B-cell lymphomas and other diseases. However, CD20 antibody failed to treat systemic lupus erythematosus (SLE or lupus). The reason for the failure is currently unknown. Type I interferons (IFN) are a major component for the host innate immunity, and a key pathogenic factor in lupus. We found that CD20 antibody potentiated human B cells for its production of IFNs in vitro. This function was specific to …

Deer Mouse Hemoglobin Exhibits A Lowered Oxygen Affinity Owing To Mobility Of The E Helix. Corrigendum, Noriko Inoguchi, Jake R. Oshlo, Chandrasekhar Natarajan, Roy E. Weber, Angela Fago, Jay F. Storz, Hideaki Moriyama

School of Biological Sciences: Faculty Publications

In the article by Inoguchi et al. (2013) the affiliation for two of the authors, Angela Fago and Roy E. Weber, was given incorrectly. The correct affiliation is Zoophysiology, Department of Bioscience, Aarhus University, Aarhus, Denmark.

Range Maps For Nebraska's Threatened And Endangered Species, Nebraska Natural Heritage Program

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This document includes maps and associated information on the ranges of Nebraska’s federal and state-listed species. The information is current as of January 2013. The information is updated as needed. Contact the Nebraska Game and Parks Commission to determine if a more current version is available. The species treated are as follows: American Burying Beetle (Nicrophorus americanus), Salt Creek Tiger Beetle (Cicindela nevadica lincolniana), Swift Fox (Vulpes velox), River Otter (Lutra canadensis), Southern Flying Squirrel (Glaucomys volans), Pallid Sturgeon (Scaphirhyncus albus), Topeka Shiner (Notropis topeka), Sturgeon Chub (Macrhybopsis gelida), Blacknose Shiner (Notropis heterolepis), Lake Sturgeon (Acipenser fulvescens), Northern Redbelly Dace …

Long-Term Nitrogen Amendment Alters The Diversity And Assemblage Of Soil Bacterial Communities In Tallgrass Prairie, Joseph D. Coolon, Kenneth L. Jones, Timothy C. Todd, John M. Blair, Michael A. Herman

School of Biological Sciences: Faculty Publications

Anthropogenic changes are altering the environmental conditions and the biota of ecosystems worldwide. In many temperate grasslands, such as North American tallgrass prairie, these changes include alteration in historically important disturbance regimes (e.g., frequency of fires) and enhanced availability of potentially limiting nutrients, particularly nitrogen. Such anthropogenically-driven changes in the environment are known to elicit substantial changes in plant and consumer communities aboveground, but much less is known about their effects on soil microbial communities. Due to the high diversity of soil microbes and methodological challenges associated with assessing microbial community composition, relatively few studies have addressed specific taxonomic changes …

A Whole-Cell Biosensor For The Detection Of Gold, Carla M. Zammit, Davide Quaranta, Shane Gibson, Anita J. Zaitouna, Christine Ta, Joel Brugger, Rebecca Y. Lai, Gregor Grass, Frank Reith

School of Biological Sciences: Faculty Publications

Geochemical exploration for gold (Au) is becoming increasingly important to the mining industry. Current processes for Au analyses require sampling materials to be taken from often remote localities. Samples are then transported to a laboratory equipped with suitable analytical facilities, such as Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) or Instrumental Neutron Activation Analysis (INAA). Determining the concentration of Au in samples may take several weeks, leading to long delays in exploration campaigns. Hence, a method for the on-site analysis of Au, such as a biosensor, will greatly benefit the exploration industry. The golTSB genes from Salmonella enterica serovar typhimurium are selectively …

Inge Revsbech Wins The Journal Of Experimental Biology’S Outstanding Paper Prize 2013, Nicola Stead, Inge G. Revsbech, Hideaki Moriyama, Jay F. Storz, Angela Fago

School of Biological Sciences: Faculty Publications

The Editors of The Journal of Experimental Biology are pleased to announce that Inge Revsbech from Aarhus University, Denmark, is the winner of this year’s JEB Outstanding paper prize. The prize is awarded in memory of Bob Boutillier (JEB Editor-in-Chief 1994–2003) to a junior author who has made the most significant contribution to an outstanding paper. ‘The prize aims to promote and reward the hard work that individual young scientists have put into solving different riddles of any particular species using ingenuity, perseverance and sound technology and methodology’, explains Hans Hoppeler, Editor-In-Chief.

Revsbech was the first author on the paper …

Role Of Merh In Mercury Resistance In The Archaeon Sulfolobus Solfataricus, James Schelert, Deepak Rudrappa, Tyler Johnson, Paul H. Blum

School of Biological Sciences: Faculty Publications

Crenarchaeota include extremely thermoacidophilic organisms that thrive in geothermal

environments dominated by sulfidic ores and heavy metals such as mercury. Mercuric ion, Hg(II),

inactivates transcription in the crenarchaeote Sulfolobus solfataricus and simultaneously

derepresses transcription of a resistance operon, merHAI, through interaction with the MerR

transcription factor. While mercuric reductase (MerA) is required for metal resistance, the role of

MerH, an adjacent small and predicted product of an ORF, has not been explored. Inactivation of

MerH either by nonsense mutation or by in-frame deletion diminished Hg(II) resistance of mutant

cells. Promoter mapping studies indicated that Hg(II) sensitivity of the merH …

Antelope Mating Strategies Facilitate Invasion Of Grasslands By A Woody Weed, Shivani Jadeja, Soumya Prasad, Suhel Quader, Kavita Isvaran

School of Biological Sciences: Faculty Publications

Intra and interspecific variation in frugivore behaviour can have important consequences for seed dispersal outcomes. However, most information comes from among-species comparisons, and within-species variation is relatively poorly understood. We examined how large intraspecific differences in the behaviour of a native disperser, blackbuck antelope Antilope cervicapra, influence dispersal of a woody invasive, Prosopis juliflora, in a grassland ecosystem. Blackbuck disperse P. juliflora seeds through their dung. In lekking blackbuck populations, males defend clustered or dispersed mating territories. Territorial male movement is restricted, and within their territories males defecate on dung-piles. In contrast, mixed-sex herds range over large areas …

Predicting Invasion In Grassland Ecosystems: Is Exotic Dominance The Real Embarrassment Of Richness?, Eric W. Seabloom, Elizabeth T. Borer, Yvonne Buckley, Elsa E. Cleland, Kendi Davies, Jennifer Firn, W. Stanley Harpole, Yann Hautier, Eric Lind, Andrew Macdougall, John L. Orrock, Suzanne M. Prober, Peter Andler, Juan Alberti, T. Michael Anderson, Jonathan D. Bakker, Lori A. Biederman, Dana Blumenthal, Cynthia S. Brown, Lars A. Brudvig, Maria Caldeira, Chengjin Chu, Michael J. Crawley, Pedro Daleo, Ellen I. Damschen, Carla M. D'Antonio, Nicole M. Decrappeo, Chris R. Dickman, Guozhen Du, Philip A. Fay, Paul Frater, Daniel S. Gruner, Nicole Hagenah, Andrew Hector, Aveliina Helm, Helmut Hillebrand, Kirsten S. Hofmockel, Hope C. Humphries, Oscar Iribarne, Virginia L. Jin, Adam Kay, Kevin P. Kirkman, Julia A. Klein, Johannes M. H. Knops, Kimberly J. La Pierre, Laura M. Ladwig, John G. Lambrinos, Andrew D. B. Leakey, Qi Li, Wei Li, Rebecca Mcculley, Brett Melbourne, Charles E. Mitchell, Joslin L. Moore, John Morgan, Brent Mortensen, Lydia R. O'Halloran, Meelis Partel, Jesus Pascual, David A. Pyke, Anita C. Risch, Roberto Salguero-Gomez, Mahesh Sankaran, Martin Schuetz, Anna Simonsen, Melinda Smith, Carly Stevens, Lauren L. Sullivan, Glenda M. Wardle, Elizabeth M. Wolkovich, Peter D. Wragg, Justin Wright, Louie Yang

School of Biological Sciences: Faculty Publications

Invasions have increased the size of regional species pools, but are typically assumed to reduce native diversity. However, global-scale tests of this assumption have been elusive because of the focus on exotic species richness, rather than relative abundance. This is problematic because low invader richness can indicate invasion resistance by the native community or, alternatively, dominance by a single exotic species. Here, we used a globally replicated study to quantify relationships between exotic richness and abundance in grass-dominated ecosystems in 13 countries on six continents, ranging from salt marshes to alpine tundra. We tested effects of human land use, native …

The Mid-Domain Effect: It’S Not Just About Space, Andrew D. Letten, S. Kathleen Lyons, Angela T. Moles

School of Biological Sciences: Faculty Publications

Ecologists and biogeographers have long sought to understand how and why diversity varies across space. Up until the late 20th century, the dominant role of environmental gradients and historical processes in driving geographical species richness patterns went largely undisputed. However, almost 20 years ago, Colwell & Hurtt (1994) proposed a radical reappraisal of ecological gradient theory that called into question decades of empirical and theoretical research. That controversial idea was later termed the ‘the mid-domain effect’: the simple proposition that in the absence of environmental gradients, the random placement of species ranges within a bounded domain will give rise to …

Different Modes Of Evolution In Males And Females Generate Dichromatism In Fairy-Wrens (Maluridae), Allison E. Johnson, J. Jordan Price, Stephen Pruett-Jones

School of Biological Sciences: Faculty Publications

Sexual dichromatism in birds is often attributed to selection for elaboration in males. However, evolutionary changes in either sex can result in plumage differences between them, and such changes can result in either gains or losses of dimorphism. We reconstructed the evolution of plumage colors in both males and females of species in Maluridae, a family comprising the fairy-wrens (Malurus, Clytomias, Sipodotus), emu-wrens (Stipiturus), and grasswrens (Amytornis). Our results show that, across species, males and females differ in their patterns of color evolution. Male plumage has diverged at relatively steady rates, whereas …

Candida Albicans Czf1 And Efg1 Coordinate The Response To Farnesol During Quorum Sensing, White-Opaque Thermal Dimorphism, And Cell Death, Melanie L. Langford, Jessica C. Hargarten, Krista D. Patefield, Elizabeth Marta, Jill R. Blankenship, Saranna Fanning, Kenneth W. Nickerson, Audrey L. Atkin

School of Biological Sciences: Faculty Publications

Quorum sensing by farnesol in Candida albicans inhibits filamentation and may be directly related to its ability to cause both mucosal and systemic diseases. The Ras1-cyclic AMP signaling pathway is a target for farnesol inhibition. However, a clear understanding of the downstream effectors of the morphological farnesol response has yet to be unraveled. To address this issue, we screened a library for mutants that fail to respond to farnesol. Six mutants were identified, and the czf1Δ/czf1Δ mutant was selected for further characterization. Czf1 is a transcription factor that regulates filamentation in embedded agar and also whiteto- opaque switching. We found …

Large-Scale Spatial Synchrony And Cross-Synchrony In Acorn Production By Two California Oaks, Walter D. Koenig, Johannes M.H. Knops

School of Biological Sciences: Faculty Publications

Seed production that varies greatly from year to year, known as ‘‘masting’’ or ‘‘mast-fruiting’’ behavior, is a population-level phenomenon known to exhibit geographic synchrony extending, at least in some cases, hundreds of kilometers. The two main nonexclusive hypotheses for the driver of such geographically extensive synchrony are (1) environmental factors (the Moran effect), and (2) the mutual dependence of trees on outcrossed pollen (pollen coupling). We tested 10 predictions relevant to these two hypotheses using 18 years of acorn production data on two species of California oaks. Data were obtained across the entire ranges of the two species at 12 …

Deer Mouse Hemoglobin Exhibits A Lowered Oxygen Affinity Owing To Mobility Of The E Helix, Noriko Inoguchi, Jake R. Oshlo, Chandrasekhar Natarajan, Roy E. Weber, Angela Fago, Jay F. Storz, Hideaki Moriyama

School of Biological Sciences: Faculty Publications

The deer mouse, Peromyscus maniculatus, exhibits altitude-associated variation in hemoglobin oxygen affinity. To examine the structural basis of this functional variation, the structure of the hemoglobin was solved. Recombinant hemoglobin was expressed in Escherichia coli and was purified by ion-exchange chromatography. Recombinant hemoglobin was crystallized by the hangingdrop vapor-diffusion method using polyethylene glycol as a precipitant. The obtained orthorhombic crystal contained two subunits in the asymmetric unit. The refined structure was interpreted as the aquo-met form. Structural comparisons were performed among hemoglobins from deer mouse, house mouse and human. In contrast to human hemoglobin, deer mouse hemoglobin lacks the …

Worms, Nematoda, Scott Lyell Gardner

Scott L. Gardner Publications

Nematodes are the most speciose phylum of metazoa on earth. Not only do they occur in huge numbers as parasites of all known animal groups, but also they are found in the soils, as parasites of plants, and in large numbers in the most extreme environments, from the Antarctic dry valleys to the benthos of the ocean. They are extremely variable in their morphological characteristics, with each group showing morphological adapta­tions to the environment that they inhabit. Soil-dwelling forms are extremely small; many marine species have long and complex setae; and parasitic species man­ifest amazingly great reproductive potential and large …

Reductive Evolution And The Loss Of Pdc/Pas Domains From The Genus Staphylococcus, Neethu Shah, Rosmarie Gaupp, Hideaki Moriyama, Kent M. Eskridge, Etsuko N. Moriyama, Greg A. Somerville

School of Biological Sciences: Faculty Publications

Background: The Per-Arnt-Sim (PAS) domain represents a ubiquitous structural fold that is involved in bacterial sensing and adaptation systems, including several virulence related functions. Although PAS domains and the subclass of PhoQ-DcuS-CitA (PDC) domains have a common structure, there is limited amino acid sequence similarity. To gain greater insight into the evolution of PDC/PAS domains present in the bacterial kingdom and staphylococci in specific, the PDC/PAS domains from the genomic sequences of 48 bacteria, representing 5 phyla, were identified using the sensitive search method based on HMM-to-HMM comparisons (HHblits).

Results: A total of 1,007 PAS domains and 686 …

Heritability And Inter-Population Differences In Lipid Profiles Of Drosophila Melanogaster, Cornelia J. F. Scheitz, Yu Guo, Angela M. Early, Lawrence G. Harshman, Andrew G. Clark

School of Biological Sciences: Faculty Publications

Characterizing and understanding the complex spectrum of lipids in higher organisms lags far behind our analysis of genome and transcriptome sequences. Here we generate and evaluate comprehensive lipid profiles (>200 lipids) of 92 inbred lines from five different Drosophila melanogaster populations. We find that the majority of lipid species are highly heritable, and even lipids with odd-chain fatty acids, which cannot be generated by the fly itself, also have high heritabilities. Abundance of the endosymbiont Wolbachia, a potential provider of odd-chained lipids, was positively correlated with this group of lipids. Additionally, we show that despite years of laboratory …

Conformational B-Cell Epitope Prediction On Antigen Protein Structures: A Review Of Current Algorithms And Comparison With Common Binding Site Prediction Methods, Bo Yao, Dandan Zheng, Shide Liang, Chi Zhang

School of Biological Sciences: Faculty Publications

Accurate prediction of B-cell antigenic epitopes is important for immunologic research and medical applications, but compared with other bioinformatic problems, antigenic epitope prediction is more challenging because of the extreme variability of antigenic epitopes, where the paratope on the antibody binds specifically to a given epitope with high precision. In spite of the continuing efforts in the past decade, the problem remains unsolved and therefore still attracts a lot of attention from bioinformaticists. Recently, several discontinuous epitope prediction servers became available, and it is intriguing to review all existing methods and evaluate their performances on the same benchmark. In addition, …

Creating An Interdisciplinary Research Course In Mathematical Ecology, Glenn Ledder, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

An integrated interdisciplinary research course in biology and mathematics is useful for recruiting students to interdisciplinary research careers, but there are difficulties involved in creating and implementing it. We describe the genesis, objectives, design policies, and structure of the Research Skills in Theoretical Ecology course at the University of Nebraska–Lincoln and discuss the difficulties that can arise in designing and implementing interdisciplinary courses.

An Interdisciplinary Research Course In Theoretical Ecology For Young Undergraduates, Glenn Ledder, Brigitte Tenhumberg, G. Travis Adams

School of Biological Sciences: Faculty Publications

As part of an interdepartmental effort to attract promising young students to research at the interface between mathematics and biology, we created a course in which groups of recent high school graduates and first-year college students conducted a research project in insect population dynamics. The students set up experiments, collected data, used the data to develop mathematical models, tested their models against further experiments, and prepared their results for dissemination. The course was self-contained in that the lecture portion developed the mathematical, statistical, and biological background needed for the research. A special writing component helped students learn the principles of …

Prevalence And Correlates Of Kaposi’S Sarcoma-Associated Herpesvirus Infection In A Sample Of Men Who Have Sex With Men In Eastern China, T. Zhang, H. Lin, V. Minhas, W. Zhu, Charles Wood, N. He

School of Biological Sciences: Faculty Publications

This study aimed to determine the seroprevalence of Kaposi’s sarcoma-associated herpesvirus (KSHV) and related factors in men who have sex with men (MSM) in China. A total of 208 subjects were recruited from eastern China from 2008 to 2009. Plasma samples were collected and screened for KSHV, HIV and syphilis. Overall, KSHV seroprevalence was 32.7% in the subjects. About 92.7% of subjects reported having ever had anal sex with a man, of whom 67.8% had receptive anal sex and 77.9% had insertive anal sex. About 93.1% of the study participants reported having had oral sex with a man, of whom …