Genetics and Genomics Commons^™

Genetically Based Low Oxygen Affinities Of Felid Hemoglobins: Lack Of Biochemical Adaptation To High-Altitude Hypoxia In The Snow Leopard, Jan E. Janecka, Simone S. E. Nielsen, Sidsel D. Andersen, Federico G. Hoffmann, Roy E. Weber, Trevor Anderson, Jay F. Storz, Angela Fago

School of Biological Sciences: Faculty Publications

Genetically based modifications of hemoglobin (Hb) function that increase blood–O₂ affinity are hallmarks of hypoxia adaptation in vertebrates. Among mammals, felid Hbs are unusual in that they have low intrinsic O₂ affinities and reduced sensitivities to the allosteric cofactor 2,3-diphosphoglycerate (DPG). This combination of features compromises the acclimatization capacity of blood–O2 affinity and has led to the hypothesis that felids have a restricted physiological niche breadth relative to other mammals. In seeming defiance of this conjecture, the snow leopard (Panthera uncia) has an extraordinarily broad elevational distribution and occurs at elevations above 6000 m in the Himalayas. Here, …

Characterization Of The Ecological Role Of Genes Mediating Acid Resistance In Lactobacillus Reuteri During Colonization Of The Gastrointestinal Tract, Janina A. Krumbeck, Nathan L Marsteller, Steven Frese, Daniel A. Peterson, Amanda Ramer-Tait, Robert W. Hutkins, Jens Walter

Department of Food Science and Technology: Faculty Publications

Rodent-derived strains of Lactobacillus reuteri densely colonize the forestomach of mice and possess several genes whose predicted functions constitute adaptations towards an acidic environment. The objective of this study was to systematically determine which genes of L. reuteri 100-23 contribute to tolerance towards host gastric acid secretion. Genes predicted to be involved in acid resistance were inactivated, and their contribution to survival under acidic conditions was confirmed in model gastric juice. Fitness of five mutants that showed impaired in vitro acid resistance were then compared through competition experiments in ex-germ-free mice that were either treated with omeprazole, a proton-pump inhibitor …

Steps In Metagenomics: Let’S Avoid Garbage In And Garbage Out, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Is metagenomics a revolution or a new fad? Metagenomics is tightly associated with the availability of next-generation sequencing in all its implementations. The key feature of these new technologies, moving beyond the Sanger-based DNA sequencing approach, is the depth of nucleotide sequencing per sample.Knowing much more about a sample changes the traditional paradigms of “What is the most abundant?” or “What is the most significant?” to “What is present and potentially sig­nificant that might influence the situation and outcome?” Let’s take the case of identifying proper biomarkers of disease state in the context of chronic disease prevention. Prevention has been …

Identifying Glioblastoma Gene Networks Based On Hypergeometric Test Analysis, Vasileios Stathias, Chiara Pastori, Tess Z. Griffin, Ricardo Komotar, Jennifer L. Clarke, Ming Zhang, Nagi G. Ayad

Department of Statistics: Faculty Publications

Patient specific therapy is emerging as an important possibility for many cancer patients. However, to identify such therapies it is essential to determine the genomic and transcriptional alterations present in one tumor relative to control samples. This presents a challenge since use of a single sample precludes many standard statistical analysis techniques. We reasoned that one means of addressing this issue is by comparing transcriptional changes in one tumor with those observed in a large cohort of patients analyzed by The Cancer Genome Atlas (TCGA). To test this directly, we devised a bioinformatics pipeline to identify differentially expressed genes in …

The Unseen World: Environmental Microbial Sequencing And Identification Methods For Ecologists, Naupaka Zimmerman, Jacques Izard, Christian Klatt, Jizhong Zhou, Emma Aronson

Department of Food Science and Technology: Faculty Publications

Archaea, bacteria, microeukaryotes, and the viruses that infect them (collectively “microorganisms”) are foundational components of all ecosystems, inhabiting almost every imaginable environment and comprising the majority of the planet’s organismal and evolutionary diversity. Microorganisms play integral roles in ecosystem functioning; are important in the biogeochemical cycling of carbon (C), nitrogen (N), sulfur (S), phosphorus (P), and various metals (eg Barnard et al. 2005); and may be vital to ecosystem responses to large-scale climatic change. Rarely found alone, microorganisms often form complex communities that are dynamic in space and time. For these and other reasons, ecologists and environmental scientists have become …

Genetic Parameter Estimates And Breed Effects For Calving Difficulty And Birth Weight In A Multi-Breed Population, Cashley Ahlberg

Department of Animal Science: Dissertations, Theses, and Student Research

There are multiple breeds of beef cattle available to utilize in breeding systems to maximize production and economics. Calving difficulty (dystocia) is a significant cost to beef production and is more prevalent in first-calf heifers. The objectives of this study were to estimate genetic parameters and breed differences for calving difficulty and birth weight as a first step towards the development of across-breed adjustment factors for calving difficulty.

Two models were employed to analyze birth weight (BWT) and calving difficulty (CD) recorded on 4,579 first parity females from the Germplasm Evaluation program at the United States Meat Animal Research Center …

Comparative Genomics Reveals Insights Into Avian Genome Evolution And Adaptation, Guojie Zhang, Cai Li, Qiye Li, Bo Li, Dennis M. Larkin, Chul Lee, Jay F. Storz, Agostinho Antunes, Matthew J. Greenwold, Robert W. Meredith, Anders Ödeen, Jie Cui, Qi Zhou, Luohao Xu, Hailin Pan, Zongji Wang, Lijun Jin, Pei Zhang, Haofu Hu, Wei Yang, Jiang Hu, Jin Xiao, Zhikai Yang, Yang Liu, Qiaolin Xie, Hao Yu, Jinmin Lian, Ping Wen, Fang Zhang, Hui Li, Yongli Zeng, Zijun Xiong, Shiping Liu, Long Zhou, Zhiyong Huang, Na An, Jie Wang, Quimei Zheng, Yingqi Xiong, Guangbiao Wang, Bo Wang, Jingjing Wang, Yu Fan, Rute R. Da Fonseca, Alonzo Alfaro-Núñez, Mikkel Schubert, Ludovic Orlando, Tobias Mourier, Jason T. Howard, Ganeshkumar Ganapathy, Andreas Pfenning, Osceola Whitney, Miriam V. Rivas, Erina Hara, Julia Smith, Marta Farré, Jitendra Narayan, Gancho Slavov, Michael N. Romanov, Rui Borges, João Paulo Machado, Imran Khan, Mark S. Springer, John Gatesy, Federico G. Hoffmann, Juan C. Opazo, Olle Håstad, Roger H. Sawyer, Heebal Kim, Kyu-Won Kim, Hyeon Jeong Kim, Seoae Cho, Ning Li, Yinhua Huang, Michael W. Bruford, Xiangjiang Zhan, Andrew Dixon, Mads F. Bertelsen, Elizabeth Derryberry, Wesley Warren, Richard K. Wilson, Shengbin Li, David A. Ray, Richard E. Green, Stephen J. O'Brien, Darren Griffin, Warren E. Johnson, David Haussler, Oliver A. Ryder, Eske Willerslev, Gary R. Graves, Per Alström, Jon Fjeldså, David P. Mindell, Scott V. Edwards, Edward L. Braun, Carsten Rahbek, David W. Burt, Peter Houde, Yong Zhang, Huanming Yang, Jian Wang, Avian Genome Consortium, Erich D. Jarvis, M. Thomas P. Gilbert, Jun Wang

Jay F. Storz Publications

Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses …

Chlorovirus Atcv-1 Is Part Of The Human Oropharyngeal Virome And Is Associated With Changes In Cognitive Functions In Humans And Mice, Robert H. Yolken, Lorraine Jones-Brando, David D. Dunigan, Geetha Kannan, Faith Dickerson, Emily Severance, Sarven Sabunciyan, C. Conover Talbot Jr., Emese Prandovszky, James R. Gurnon, Irina V. Agarkova, Flora Leister, Kristin L. Gressitt, Ou Chen, Bryan Deuber, Fangrui Ma, Mikhail V. Pletnikov, James L. Van Etten

James Van Etten Publications

Chloroviruses (family Phycodnaviridae) are large DNA viruses known to infect certain eukaryotic green algae and have not been previously shown to infect humans or to be part of the human virome. We unexpectedly found sequences homologous to the chlorovirus Acanthocystis turfacea chlorella virus 1 (ATCV-1) in a metagenomic analysis of DNA extracted from human oropharyngeal samples. These samples were obtained by throat swabs of adults without a psychiatric disorder or serious physical illness who were participating in a study that included measures of cognitive functioning. The presence of ATCV-1 DNA was confirmed by quantitative PCR with ATCV-1 DNA being …

Eight Legged Encounters, Eileen A. Hebets

Eileen Hebets Publications

This program was funded in part by a National Science Foundation grant (DRL–1241482 to EAH). Material was developed in collaboration with Marie- Claire Chelini, Jessie Rose Storz, Cody Storz, and Malcolm Rosenthal. Steven Schwartz, Jason Stafstrom, Kathy French, Priscilla Grew, and Judy Diamond were all extremely helpful in grant writing, facilitating the first live event, and/or discussions. Pawl Tisdale (artist) was phenomenal to work with on all aspects of the project!

TABLE OF CONTENTS

CLASSIFICATION & TAXONOMY STATIONS
I. WHAT IS AN ARTHROPOD? page 4 a. The goal of this station is to introduce the audience to some basic information …

Altered Theca And Cumulus Oocyte Complex Gene Expression, Follicular Arrest And Reduced Fertility In Cows With Dominant Follicle Follicular Fluid Androgen Excess, Adam F. Summers, William E. Pohlmeier, Kevin M. Sargent, Brizett D. Cole, Rebecca J. Vinton, Scott G. Kurz, Renee M. Mcfee, Robert A. Cushman, Andrea S. Cupp, Jennifer R. Wood

Department of Animal Science: Faculty Publications

Aspiration of bovine follicles 12–36 hours after induced corpus luteum lysis serendipitously identified two populations of cows, one with High androstenedione (A4; >40 ng/ml; mean = 102) and another with Low A4 (/ml; mean = 9) in follicular fluid. We hypothesized that the steroid excess in follicular fluid of dominant follicles in High A4 cows would result in reduced fertility through altered follicle development and oocyte maternal RNA abundance. To test this hypothesis, estrous cycles of cows were synchronized and ovariectomy was performed 36 hours later. HPLC MS/MS analysis of follicular fluid showed increased dehydroepiandrosterone (6-fold), A4 (158-fold) and testosterone …

Kernel-Based Whole-Genome Prediction Of Complex Traits: A Review, Gota Morota, Daniel Penagaricano

Department of Animal Science: Faculty Publications

Prediction of genetic values has been a focus of applied quantitative genetics since the beginning of the 20th century, with renewed interest following the advent of the era of whole genome-enabled prediction. Opportunities offered by the emergence of high-dimensional genomic data fueled by post-Sanger sequencing technologies, especially molecular markers, have driven researchers to extend Ronald Fisher and Sewall Wright’s models to confront new challenges. Inparticular, kernel methods are gaining consideration as a regression method of choice for genome-enabled prediction. Complex traits are presumably influenced by many genomic regions working in concert with others (clearly so when considering pathways), thus generating …

Advancing The Microbiome Research Community, Curtis Huttenhower, Rob Knight, C. Titus Brown, J. Gregory Caporaso, Jose C. Clemente, Dirk Gevers, Eric A. Franzosa, Scott T. Kelley, Dan Knights, Ruth E. Ley, Anup Mahurkar, Jacques Ravel, Scientists For Advancement Of Microbiome Research, Owen White, Jacques Izard

Department of Food Science and Technology: Faculty Publications

The human microbiome has become a recognized factor in promoting and maintaining health. We outline opportunities in interdisciplinary research, analytical rigor, standardization, and policy development for this relatively new and rapidly developing field. Advances in these aspects of the research community may in turn advance our understanding of human microbiome biology.

It is now widely recognized that disturbances in our normal microbial populations may be linked to acute infections such as Clostridium difficile and to chronic diseases such as heart disease, cancer, obesity, and autoimmune disorders. This has prompted substantial interest in the microbiome from both basic and clinical perspectives. …

Dangerous Mating Systems: Signal Complexity, Signal Content And Neural Capacity In Spiders, Marie E. Herberstein, Anne E. Wignall, Eileen Hebets, Jutta M. Schneider

Eileen Hebets Publications

Spiders are highly efficient predators in possession of exquisite sensory capacities for ambushing prey, combined with machinery for launching rapid and determined attacks. As a consequence, any sexually motivated approach carries a risk of ending up as prey rather than as a mate. Sexual selection has shaped courtship to effectively communicate the presence, identity, motivation and/or quality of potential mates, which help ameliorate these risks. Spiders communicate this information via several sensory channels, including mechanical (e.g. vibrational), visual and/or chemical, with examples of multimodal signaling beginning to emerge in the literature. The diverse environments that spiders inhabit have further shaped …

Multimodal Sensory Reliance In The Nocturnal Homing Of The Amblypygid Phrynus Pseudoparvulus (Class Arachnida, Order Amblypygi)?, Eileen A. Hebets, Alfonso Aceves-Aparicio, Samuel Aguilar-Argüello, Verner P. Bingman, Ignacio Escalante, Eben J. Gering, David R. Nelson, Jennifer Rivera, José Ángel Sánchez-Ruiz, Laura Segura-Hernández, Virginia Settepani, Daniel D. Wiegmann, Jay A. Stafstrom

Eileen Hebets Publications

Like many other nocturnal arthropods, the amblypygid Phrynus pseudoparvulus is capable of homing. The environment through which these predators navigate is a dense and heterogeneous tropical forest understory and the mechanism(s) underlying their putatively complex navigational abilities are presently unknown. This study explores the sensory inputs that might facilitate nocturnal navigation in the amblypygid P. pseudoparvulus. Specifically, we use sensory system manipulations in conjunction with field displacements to examine the potential involvement of multimodal—olfactory and visual—stimuli in P. pseudoparvulus’ homing behavior. In a first experiment, we deprived individuals of their olfactory capacity and displaced them to the opposite side of …

Investigating The Role Of Micrornas In The Response To Nitrogen Deprivation In The Green Alga Chlamydomonas Reinhardtii, Adam Voshall

School of Biological Sciences: Dissertations, Theses, and Student Research

Microalgae are gaining attention as a potential feedstock for the production of biodiesel, mainly derived from triacylglycerols (TAG). In many algae, TAG synthesis increases dramatically upon certain stresses but this is often accompanied by growth retardation. Rational improvements to strain productivity are limited by the scant knowledge on algal lipid metabolism and gene regulatory mechanisms. In this context, systems-level approaches aimed at understanding and modeling metabolic and regulatory networks may enable hypothesis-driven genetic engineering strategies. The green microalga Chlamydomonas reinhardtii accumulates significant amounts of TAGs under nutrient starvation and provides a genetically tractable model for manipulating biosynthetic pathways. In order …

De Novo Transcriptome Of The Hemimetabolous German Cockroach (Blattella Germanica), Xiaojie Zhou, Kun Qian, Ying Tong, Junwei Jerry Zhu, Xinghui Qiu, Xiaopeng Zeng

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: The German cockroach, Blattella germanica, is an important insect pest that transmits various pathogens mechanically and causes severe allergic diseases. This insect has long served as a model system for studies of insect biology, physiology and ecology. However, the lack of genome or transcriptome information heavily hinder our further understanding about the German cockroach in every aspect at a molecular level and on a genome-wide scale. To explore the transcriptome and identify unique sequences of interest, we subjected the B. germanica transcriptome to massively parallel pyrosequencing and generated the first reference transcriptome for B. germanica.

Methodology/Principal Findings: A …

Chlorovirus Skp1-Binding Ankyrin Repeat Protein Interplay And Mimicry Of Cellular Ubiquitin Ligase Machinery, Eric A. Noel, Ming Kang, Jiri Adamec, James L. Van Etten, George A. Oyler

James Van Etten Publications

The ubiquitin-proteasome system is targeted by many viruses that have evolved strategies to redirect host ubiquitination machinery. Members of the genus Chlorovirus are proposed to share an ancestral lineage with a broader group of related viruses, nucleo-cytoplasmic large DNA viruses (NCLDV). Chloroviruses encode an Skp1 homolog and ankyrin repeat (ANK) proteins. Several chlorovirus-encoded ANK repeats contain C-terminal domains characteristic of cellular F-boxes or related NCLDV chordopox PRANC (pox protein repeats of ankyrin at C-terminal) domains. These observations suggested that this unique combination of Skp1 and ANK repeat proteins might form complexes analogous to the cellular Skp1-Cul1-F-box (SCF) ubiquitin ligase complex. …

The Trehalose Pathway In Maize: Conservation And Gene Regulation In Response To The Diurnal Cycle And Extended Darkness, Clémence Henry, Samuel W. Bledsoe, Allison Siekman, Alec Kollman, Brian M. Waters, Regina Feil, Mark Stitt, L. Mark Lagrimini

Department of Agronomy and Horticulture: Faculty Publications

Energy resources in plants are managed in continuously changing environments, such as changes occurring during the day/night cycle. Shading is an environmental disruption that decreases photosynthesis, compromises energy status, and impacts on crop productivity. The trehalose pathway plays a central but not well-defined role in maintaining energy balance. Here, we characterized the maize trehalose pathway genes and deciphered the impacts of the diurnal cycle and disruption of the day/night cycle on trehalose pathway gene expression and sugar metabolism. The maize genome encodes 14 trehalose-6-phosphate synthase (TPS) genes, 11 trehalose-6-phosphate phosphatase (TPP) genes, and one trehalase gene. Transcript abundance of most …

Imaging Luciferase-Expressing Viruses, Michael A. Barry, Shannon May, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

Optical imaging of luciferage gene expression has become a powerful tool to track cells and viruses in vivo in small animal models. Luciferase imaging has been used to study the location of infection by replication-defective and replication-competent viruses and to track changes in the distribution of viruses in mouse models. This approach has also been used in oncolytic studies as a non-invasive means to monitor the growth and killing of tumor cells modified with luciferase genes. In this chapter, we describe the techniques used for luciferase imaging as have been applied to track replication-defective and replication-competent adenoviruses in mouse and …

Choline And Choline Metabolite Patterns And Associations In Blood And Milk During Lactation In Dairy Cows, Virginia M. Artegoitia, Jesse L. Foote, Federico M. Harte, Shawn R. Campagna, Michael J. De Veth

Department of Animal Science: Faculty Publications

Milk and dairy products are an important source of choline, a nutrient essential for human health. Infant formula derived from bovine milk contains a number of metabolic forms of choline, all contribute to the growth and development of the newborn. At present, little is known about the factors that influence the concentrations of choline metabolites in milk. The objectives of this study were to characterize and then evaluate associations for choline and its metabolites in blood and milk through the first 37 weeks of lactation in the dairy cow. Milk and blood samples from twelve Holstein cows were collected in …

Chlorovirus Pbcv-1 Encodes An Active Copper-Zinc Superoxide Dismutase, Ming Kang, Garry A. Duncan, Charles Kuszynski, George Oyler, Jiayin Zheng, Donald F. Becker, James L. Van Etten

James Van Etten Publications

Superoxide dismutases (SODs) are metalloproteins that protect organisms from toxic reactive oxygen species by catalyzing the conversion of superoxide anion to hydrogen peroxide and molecular oxygen. Chlorovirus PBCV-1 encodes a 187-amino-acid protein that resembles a Cu-Zn SOD with all of the conserved amino acid residues for binding copper and zinc (named cvSOD). cvSOD has an internal Met that results in a 165-amino-acid protein (named tcvSOD). Both cvSOD and tcvSOD recombinant proteins inhibited nitroblue tetrazolium reduction of superoxide anion generated in a xanthine-xanthine oxidase system in solution. tcvSOD was chosen for further characterization because it was easier to produce. Recombinant tcvSOD …

Rna Interference As A Tool For The Functional Analysis Of Genes In The Colorado Potato Beetle, Leptinotarsa Decemlineata (Say), Ashley Danielle Yates

Department of Entomology: Dissertations, Theses, and Student Research

RNA interference (RNAi) is a naturally occurring phenomenon in eukaryotes in which a double-stranded RNA (dsRNA) suppresses the expression of a target gene. RNAi has markedly changed the way in which functional genetics studies are performed, especially in non-model organisms. In insects, the efficacy of RNAi is influenced by several factors, including the species and the methods of dsRNAs delivery.

The Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), is a pest of the plant family Solanaceae. RNAi in the CPB is of interest for potential use in insect management and as a tool to study the interaction with host plants. …

Expression Of Chlorovirus Mt325 Aquaglyceroporin (Aqpv1) In Tobacco And Its Role In Mitigating Drought Stress, Saadia Bihmidine, Mingxia Cao, Ming Kang, Tala Awada, James L. Van Etten, David Dunigan, Thomas E. Clemente

James Van Etten Publications

Main conclusions A Chlorovirus aquaglyceroporin expressed in tobacco is localized to the plastid and plasma membranes. Transgenic events display improved response to water deficit. Necrosis in adult stage plants is observed.

Aquaglyceroporins are a subclass of the water channel aquaporin proteins (AQPs) that transport glycerol along with other small molecules transcellular in addition to water. In the studies communicated herein, we analyzed the expression of the aquaglyceroporin gene designated, aqpv1, from Chlorovirus MT325, in tobacco (Nicotiana tabacum), along with phenotypic changes induced by aqpv1 expression in planta. Interestingly, aqpv1 expression under control of either a constitutive or …

Functional Genomics Of Maize Endosperm Maturation And Protein Quality, Lingling Yuan

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Maize is one of the most important cereal crops and widely cultivated throughout the world. The study on maize kernel development including protein quality improvement is essential for removing dietary protein deficiency because of the lack of essential amino acids, especially lysine and tryptophan, in maize kernel. Quality Protein Maize (QPM) is a hard kernel variant of the high-lysine mutant, opaque-2. We created opaque QPM variants to identify opaque-2 modifier genes and to investigate deletion mutagenesis combined with Illumina sequencing as a maize functional genomics tool. A K0326Y-QPM deletion mutant, line 107, was null for the 27- and 50-kD …

Obligate Male Death And Sexual Cannibalism In Dark Fishing Spiders, Steven Schwartz, William E. Wagner, Eileen A. Hebets

Eileen Hebets Publications

Male dark fishing spiders (Dolomedes tenebrosus Araneae, Pisauridae) always die during their first and only copulation, making all males monogynous. Such obligate male death can be adaptive if it facilitates sexual cannibalism, and if sexual cannibalism results in male reproductive benefits, such as an advantage in sperm competition through reduced female remating. We first conducted an experiment to determine the extent to which D. tenebrosus (1) males are cannibalized by females and (2) females engage in remating, both of which are prerequisites for several adaptive hypotheses of male self-sacrifice. We then conducted an experiment to test the hypothesis that …

Ept7 Influences Estrogen Action In The Pituitary Gland And Body Weight Of Rats, Scott G. Kurz, Kirsten L. Mcfee, Nyssa Becker Samanas, Maureen Peters Hickman, Quincy A. Eckert, Tiffany L. Walker, Andrea S. Cupp, James D. Shull

Department of Animal Science: Faculty Publications

Estrogens control many aspects of pituitary gland biology, including regulation of lactotroph homeostasis and synthesis and secretion of prolactin. In rat models, these actions are strain specific and heritable, and multiple quantitative trait loci (QTL) have been mapped that impact the responsiveness of the lactotroph to estrogens. One such QTL, Ept7, was mapped to RNO7 in female progeny generated in an intercross between BN rats, in which the lactotroph population is insensitive to estrogens, and ACI rats, which develop lactotroph hyperplasia/adenoma and associated hyperprolactinemia in response to estrogen treatment. The primary objective of this study was to confirm the …

The Evolution Of Respiratory O2/No Reductases: An Out-Of-The-Phylogenetic-Box Perspective, Anne-Lise Ducluzeau, Barbara Schoepp-Cothenet, Robert Van Lis, Frauke Baymann, Michael J. Russell, Wilfgang Nitschke

Department of Biochemistry: Faculty Publications

Complex life on our planet crucially depends on strong redox disequilibria afforded by the almost ubiquitous presence of highly oxidizing molecular oxygen. However, the history of O₂-levels in the atmosphere is complex and prior to the Great Oxidation Event some 2.3 billion years ago, the amount of O₂ in the biosphere is considered to have been extremely low as compared with present-day values. Therefore the evolutionary histories of life and of O₂-levels are likely intricately intertwined. The obvious biological proxy for inferring the impact of changing O₂-levels on life is the evolutionary history …

Lifecycle Efficiency Of Mice Divergently Selected For Heat Loss, Adrienne Bhatnagar

Department of Animal Science: Dissertations, Theses, and Student Research

Divergent selection for heat loss as an indication of maintenance energy requirements in mice resulted in a low (ML) and high maintenance line (MH), and an intermediate control line (MC). Improved feed efficiency has been observed in ML mice, which would be economically beneficial in livestock species. However, previous work showed evidence of unfavorable correlated responses to selection in ML mice compared to MH mice. Therefore, the objective of this study was to model a lifecycle similar to a livestock production system using these lines and determine if these correlated responses diminish the benefit of improved feed efficiency by calculating …

Tactical Adjustment Of Signaling Leads To Increased Mating Success And Survival, Laura Sullivan-Beckers, Eileen A. Hebets

Eileen Hebets Publications

Most sexually reproducing animals overcome the challenge of searching for and attracting mates by utilizing signals that are broadcast through a spatially and temporally varying environment. A diverse suite of behavioral solutions exist for overcoming such environmental variability, including the adjustment of signaling behavior based upon receiver feedback. Few studies have directly examined the relationship between such tactical signaling adjustments and proxies of male fitness; the few that have, failed to find a relationship. Using the wolf spider, Schizocosa rovneri, we set out to first quantify among-male variation in the form and degree of responsiveness to female feedback. Following …

Investigations Into Sensory Ecology And Gene Evolution Of The Pea Aphid (Acyrthosiphon Pisum), Swapna R. Purandare

School of Biological Sciences: Dissertations, Theses, and Student Research

Organisms use environmental cues to gather information required to perform activities that are essential for their survival and reproduction, such as searching for food, avoiding danger, and finding mates. They respond to the acquired information by changing their behavior or physiology, which may result in increased fitness. Due to the fundamental importance of information in an organism’s life, it is important to understand its acquisition, processing, and the organism’s response to it. In the work presented here, we used the pea aphid (Acyrthosiphon pisum), an insect that produces multiple phenotypes, or morphs, that are genetically identical, but differ …