Biology Commons^™

Dengue Virus Infection Perturbs Lipid Homeostasis In Infected Mosquito Cells., Rushika Perera, Catherine Riley, Giorgis Isaac, Amber S. Hopf-Jannasch, Ronald J. Moore, Karl W. Weitz, Ljiljana Pasa-Tolic, Thomas O. Metz, Jiri Adamec, Richard J. Kuhn

Department of Biological Sciences Faculty Publications

Dengue virus causes ~50–100 million infections per year and thus is considered one of the most aggressive arthropod-borne human pathogen worldwide. During its replication, dengue virus induces dramatic alterations in the intracellular membranes of infected cells. This phenomenon is observed both in human and vector-derived cells. Using high-resolution mass spectrometry of mosquito cells, we show that this membrane remodeling is directly linked to a unique lipid repertoire induced by dengue virus infection. Specifically, 15% of the metabolites detected were significantly different between DENV infected and uninfected cells while 85% of the metabolites detected were significantly different in isolated replication complex …

Ecosystem Service Tradeoff Analysis Reveals The Value Of Marine Spatial Planning For Multiple Ocean Uses, Crow White, Benjamin S. Halpern, Carrie V. Kappel

Biological Sciences

Marine spatial planning (MSP) is an emerging responsibility of resource managers around the United States and elsewhere. A key proposed advantage of MSP is that it makes tradeoffs in resource use and sector (stakeholder group) values explicit, but doing so requires tools to assess tradeoffs. We extended tradeoff analyses from economics to simultaneously assess multiple ecosystem services and the values they provide to sectors using a robust, quantitative, and transparent framework. We used the framework to assess potential conflicts among offshore wind energy, commercial fishing, and whale-watching sectors in Massachusetts and identify and quantify the value from choosing optimal wind …

Role Of Trehalose In Salinity And Temperature Tolerance In The Model Halophilic Bacterium Chromohalobacter Salexigens., Mercedes Reina-Bueno, Montserrat Argondona, Manuel Salvador, Javier Rodriguez-Moya, Fernando Iglesias-Guerra, Laszlo Csonka, Joaquin J. Nieto, Carmen Vargas

Department of Biological Sciences Faculty Publications

The disaccharide trehalose is considered as a universal stress molecule, protecting cells and biomolecules from injuries imposed by high osmolarity, heat, oxidation, desiccation and freezing. Chromohalobacter salexigens is a halophilic and extremely halotolerant γ-proteobacterium of the family Halomonadaceae. In this work, we have investigated the role of trehalose as a protectant against salinity, temperature and desiccation in C. salexigens. A mutant deficient in the trehalose-6-phosphate synthase gene (otsA::Ω) was not affected in its salt or heat tolerance, but double mutants ectoine- and trehalose-deficient, or hydroxyectoine-reduced and trehalose-deficient, displayed an osmo- and thermosensitive phenotype, respectively. This suggests …

By Any Other Name: Heterologous Replacement Of The Escherichia Coli Rnase P Protein Subunit Has In Vivo Fitness Consequences, Paula C.G. Turrini, Jasmine L. Loveland, Robert L. Dorit

Biological Sciences: Faculty Publications

Bacterial RNase P is an essential ribonucleoprotein composed of a catalytic RNA component (encoded by the rnpB gene) and an associated protein moiety (encoded by rnpA). We construct a system that allows for the deletion of the essential endogenous rnpA copy and for its simultaneous replacement by a heterologous version of the gene. Using growth rate as a proxy, we explore the effects on fitness of heterologous replacement by increasingly divergent versions of the RNase P protein. All of the heterologs tested complement the loss of the endogenous rnpA gene, suggesting that all existing bacterial versions of the rnpA …

Crosstalk Between Phospholipase D And Sphingosine Kinase In Plant Stress Signaling, Xuemin Wang, Liang Guo

Biology Department Faculty Works

The activation of phospholipase D (PLD) produces phosphatidic acid (PA), whereas plant sphingosine kinase (SPHK) phosphorylates long-chain bases to generate long-chain base-1-phosphates such as phytosphingosine-1-phosphate (phyto-S1P). PA and phyto-S1P have been identified as lipid messengers. Recent studies have shown that PA interacts directly with SPHKs in Arabidopsis, and that the interaction promotes SPHK activity. However, SPHK and phyto-S1P act upstream of PLDα1 and PA in the stomatal response to abscisic acid (ABA). These findings indicate that SPHK/phyto-S1P and PLD/PA are co-dependent in the amplification of lipid messengers, and that crosstalk between the sphingolipid- and phospholipid-mediated signaling pathways may play important …

Variable Effect Of Co-Infection On The Hiv Infectivity: Within-Host Dynamics And Epidemiological Significance, Diego F. Cuadros, Gisela García-Ramos

Biology Faculty Publications

BACKGROUND: Recent studies have implicated viral characteristics in accounting for the variation in the HIV set-point viral load (spVL) observed among individuals. These studies have suggested that the spVL might be a heritable factor. The spVL, however, is not in an absolute equilibrium state; it is frequently perturbed by immune activations generated by co-infections, resulting in a significant amplification of the HIV viral load (VL). Here, we postulated that if the HIV replication capacity were an important determinant of the spVL, it would also determine the effect of co-infection on the VL. Then, we hypothesized that viral factors contribute to …

The Phylogeography Of The Mountain Sucker [Catostomus (Pantosteus) Platyrhynchus], Nina Johanna Laitnen

Theses and Dissertations

Pantosteus, a subgenus of Catostomus, includes the mountain sucker (Catostomus playthyrnchus), whose speculated older origins in the Miocene/Pliocene can provide insight into the ancient geographical events of western North America. We believe that major geologic events influencing the diversification of mountain suckers include the rise of the Colorado Plateau, the connections between the ancient Snake River system and the Lahontan system and subsequently the connection of the Snake River system to the Columbia Basin, dispersal of mountain suckers across the continental divide, as well as the Pleistocene Bonneville flood. If this is true, we should see …

Design And Fatigue Study Of Intravascular Coronary Stent Using Finite Element Analysis, Jared May

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science & Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Jared May on March 15, 2012.

Levels Of Arabidopsis Thaliana Leaf Phosphatidic Acids, Phosphatidylserines, And Most Trienoate-Containing Polar Lipid Molecular Species Increase During The Dark Period Of The Diurnal Cycle, Xuemin Wang, Sara Maatta, Brad Scheu, Mary Roth, Pamela Tamura, Maoyin Li, Todd Williams, Ruth Welti

Biology Department Faculty Works

Previous work has demonstrated that plant leaf polar lipid fatty acid composition varies during the diurnal (dark–light) cycle. Fatty acid synthesis occurs primarily during the light, but fatty acid desaturation continues in the absence of light, resulting in polyunsaturated fatty acids reaching their highest levels toward the end of the dark period. In this work, Arabidopsis thaliana were grown at constant (21°C) temperature with 12-h light and 12-h dark periods. Collision induced dissociation time-of-flight mass spectrometry (MS) demonstrated that 16:3 and 18:3 fatty acid content in membrane lipids of leaves are higher at the end of the dark than at …

Evaluation Of Multiple Protein Docking Structures Using Correctly Predicted Pairwise Subunits., Juan Esquivel-Rodriguez, Daisuke Kihara

Department of Biological Sciences Faculty Publications

Background

Many functionally important proteins in a cell form complexes with multiple chains. Therefore, computational prediction of multiple protein complexes is an important task in bioinformatics. In the development of multiple protein docking methods, it is important to establish a metric for evaluating prediction results in a reasonable and practical fashion. However, since there are only few works done in developing methods for multiple protein docking, there is no study that investigates how accurate structural models of multiple protein complexes should be to allow scientists to gain biological insights.

Methods

We generated a series of predicted models (decoys) of various …

Amino Acid Function And Docking Site Prediction Through Combining Disease Variants, Structure Alignments, Sequence Alignments, And Molecular Dynamics: A Study Of The Hmg Domain, Jeremy W. Prokop, Thomas C. Leeper, Zhong-Hui Duan, Amy Milsted

Biology Faculty Research

Background: The DNA binding domain of HMG proteins is known to be important in many diseases, with the Sox sub-family of HMG proteins of particular significance. Numerous natural variants in HMG proteins are associated with disease phenotypes. Integrating these natural variants, molecular dynamic simulations of DNA interaction and sequence and structure alignments give detailed molecular knowledge of potential amino acid function such as DNA or protein interaction. Results: A total of 33 amino acids in HMG proteins are known to have natural variants in diseases. Eight of these amino acids are normally conserved in human HMG proteins and 27 are …

Effects Of Predation Environment And Food Availability On Somatic Growth In The Livebearing Fish Brachyrhaphis Rhabdophora (Pisces: Poeciliidae), Brittany Herrod Gale

Theses and Dissertations

Variation in somatic growth rates has interested biologists for decades because of the relationship between growth and other fitness-determining traits (i.e. fecundity, survival, and body size), and the corresponding effect of somatic growth on production of organisms humans use for food. The interaction between genetic variation in growth rates and environmentally induced variation in growth rates shows the pattern of growth across multiple environments (i.e. the reaction norm) that clarifies the history and potential future of evolutionary change in growth rates among populations. Theoretical predictions suggest variation in predator-induced mortality rates can influence mean growth rates and the shape of …

Pf19 Encodes The P60 Catalytic Subunit Of Katanin And Is Required For Assembly Of The Flagellar Central Apparatus In Chlamydomonas, Erin E. Dymek, Elizabeth F. Smith

Dartmouth Scholarship

For all eukaryotic cilia the basal bodies provide a template for the assembly of the doublet microtubules, and intraflagellar transport provides a mechanism for transport of axonemal components into the growing cilium. What is not known is how the central pair of microtubules is nucleated or how their associated polypeptides are assembled. Here we report that the Chlamydomonas pf19 mutation results in a single amino acid change within the p60 catalytic subunit of katanin, and that this mutation prevents microtubule severing activity. The pf19 mutant has paralyzed flagella that lack the central apparatus. Using a combination of mutant analysis, RNAi-mediated …

Accurate Spectral Measurements And Color Infrared Imagery Of Excised Leaves Exhibiting Gaussian Curvature From Healthy And Stressed Plants, Christopher R. Little, Kenneth R. Summy

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

No abstract provided.

Connections Between Sphingosine Kinase And Phospholipase D In The Abscisic Acid Signaling Pathway In Arabidopsis, Xuemin Wang, Liang Guo, Girish Mishra, Jennifer E. Markham, Maoyin Li, Amanda Tawfall, Ruth Welti

Biology Department Faculty Works

Phosphatidic acid (PA) and phytosphingosine 1-phosphate (phyto-S1P) both are lipid messengers involved in plant response to abscisic acid (ABA). Our previous data indicate that PA binds to sphingosine kinase (SPHK) and increases its phyto-S1P-producing activity. To understand the cellular and physiological functions of the PA-SPHK interaction, we isolated Arabidopsis thaliana SPHK mutants sphk1-1 and sphk2-1 and characterized them, together with phospholipase Dα1 knock-out, pldα1, in plant response to ABA. Compared with wild-type (WT) plants, the SPHK mutants and pldα1 all displayed decreased sensitivity to ABA-promoted stomatal closure. Phyto-S1P promoted stomatal closure in sphk1-1 and sphk2-1, but not in pldα1, whereas …

Phylogenetics Of Thysanoptera (Insecta: Paraneoptera), Rebecca S. Buckman

Theses and Dissertations

The order Thysanoptera (Insecta: Paraneoptera), commonly known as thrips, includes organisms that exhibit a wide range of social and feeding behaviors that are of particular interest in evolutionary studies. These studies within thrips have been inhibited by the lack of knowledge of thrips relationships. The recognized classification scheme strives to reflect evolutionary relationships and is based upon morphology. Molecular data is next as morphology alone is not enough to resolve relationships. Few molecular studies have been conducted and all were limited in their taxon sampling and genetic sampling. To provide a foundation of future evolutionary studies, the objectives of this …

Library Impact Statement For Nrs/Bio 417 Herpetology, Michael A. Cerbo Ii

Library Impact Statements

Library Impact Statement for NRU/BIO 417 Herpetology new course proposal. No new library resources are needed to support this course. Responding library faculty member: Michael A. Cerbo II. Requesting faculty member: Nancy E. Karraker.

Library Impact Statement For Nrs/Bio 517 Herpetology, Michael A. Cerbo Ii

Library Impact Statements

Library Impact Statement for NRS/BIO 517 Herpetology. No new library resources are needed to support this course. Responding library faculty member: Micael A. Cerbo II. Requesting faculty member: Nancy E. Karraker.

Tracing The Transport Of Colored Dissolved Organic Matter In Water Masses Of The Southern Beaufort Sea: Relationship With Hydrographic Characteristics, A. Matsuoka, A. Bricaud, Ronald Benner, J. Para, R. Sempéré, L. Prieur, S. Bélanger, M. Babin

Faculty Publications

Light absorption by colored dissolved organic matter (CDOM) [aCDOM(λ)] plays an important role in the heat budget of the Arctic Ocean, contributing to the recent decline in sea ice, as well as in biogeochemical processes. We investigated aCDOM(λ) in the Southern Beaufort Sea where a significant amount of CDOM is delivered by the Mackenzie River. In the surface layer, aCDOM(440) showed a strong and negative correlation with salinity, indicating strong river influence and conservative transport in the river plume. Below the mixed layer, a weak but positive correlation between aCDOM(440) and salinity was observed above the upper halocline, resulting from …

Cell Signaling. Structural Origins Of Receptor Bias, Stephen R. Sprang, Jackson Chief Elk

Biological Sciences Faculty Publications

Agonists can elicit pathway-specific conformational changes in a G protein–coupled receptor.

Unreconstructable Pilon Fractures: An Overview Of Two Surgical Approaches And Their Outcomes, Lauren Caradonna

Capstone Research Projects

Pilon fractures, or distal tibial fractures, are difficult injuries to treat, not only because of their propensity to sustain highly articulated fractures, but also because of the delicacy of the traumatized soft tissues (Johnson). Oftentimes the fracture is too comminuted to repair with open reduction and internal fixation alone (See Figure 1). The current practice of treating highly comminuted tibial fractures involves placing the patient in an external fixator which allows isolation of the tibio-talar joint so that the soft tissues can heal. After sufficient healing time the internal fixation and reduction is performed. Although this method is an improvement …

Targeted Disruption Of Toxoplasma Gondii Serine Protease Inhibitor 1 Increases Bradyzoite Cyst Formation In Vitro And Parasite Tissue Burden In Mice, Viviana Pszenny, Paul H. Davis, Xing W. Zhou, Christopher A. Hunter, Vern B. Carruthers, David S. Roos

Biology Faculty Publications

As an intracellular protozoan parasite, Toxoplasma gondii is likely to exploit proteases for host cell invasion, acquisition of nutrients, avoidance of host protective responses, escape from the parasitophorous vacuole, differentiation, and other activities. T. gondii serine protease inhibitor 1 (TgPI1) is the most abundantly expressed protease inhibitor in parasite tachyzoites. We show here that alternative splicing produces two TgPI1 isoforms, both of which are secreted via dense granules into the parasitophorous vacuole shortly after invasion, become progressively more abundant over the course of the infectious cycle, and can be detected in the infected host cell cytoplasm. To …

Add Ecology To The Pre-Medical Curriculum, George Middendorf

Department of Biology Faculty Publications

No abstract provided.

Reducing False-Positive Prediction Of Minimotifs With A Genetic Interaction Filter, Jerlin Camilus Merlin, Sanguthevar Rajasekaran, Tian Mi, Martin Schiller

Life Sciences Faculty Research

Background

Minimotifs are short contiguous peptide sequences in proteins that have known functions. At its simplest level, the minimotif sequence is present in a source protein and has an activity relationship with a target, most of which are proteins. While many scientists routinely investigate new minimotif functions in proteins, the major web-based discovery tools have a high rate of false-positive prediction. Any new approach that reduces false-positives will be of great help to biologists.

Methods and Findings

We have built three filters that use genetic interactions to reduce false-positive minimotif predictions. The basic filter identifies those minimotifs where the source/target …

Ear Length As A Diagnostic Character For Identifying Species Of Kangaroo Rats, Daniel W. Ziebron

Biological Sciences

The following study examines the use of ear length as a diagnostic field character for differentiating between species of Kangaroo rats in San Luis Obispo County. Data was taken from a study of Kangaroo rats in the Guadalupe-Nipomo Dunes National Wildlife Refuge, as well as various collections under the supervision of Francis X. Villablanca, Ph. D. and California Polytechnic State University, San Luis Obispo. An ANOVA was used to compare subspecies within Dipodomys heermanni and t-tests were used to compare ear lengths between Dipodomys heermanni and Dipodomys venustus. The analysis shows a statistically significant difference and supports the hypothesis …

Science & The Senses: Perceptions & Deceptions, William D. Stansfield

Biological Sciences

Science requires the acquisition and analysis of empirical (sense-derived) data. Given the same physical objects or phenomena, the sense organs of all people do not respond equally to these stimuli, nor do their minds interpret sensory signals identically. Therefore, teachers should develop lectures on human sensory systems that include some common examples of sensory limitations, variations, deficiencies, malfunctions, and diseases (as discussed herein) because they have important implications for conducting scientific investigations, science education, and introspection that are seldom included in biology textbooks. Students need to be made aware of the human tendency to self deception in order to avoid …

Potential For Barn Owl As Rodent Biological Control In Central California Vineyards, Hannah Tillmann

Biological Sciences

The pocket gopher (Thomomys bottae) and voles (Microtus spp.) cause significant economic damage to vineyards. In response, many growers have taken steps to attract Barn Owls (Tyto alba) to their properties to help keep these rodent populations in check. This research project investigated Barn Owl consumption of pocket gophers and voles in Central California vineyards in order to assess the efficiency of this integrated pest management strategy. I collected a total of 715 owl pellets from five vineyard locations in Templeton and Paso Robles, California over an eight-month period during nesting and post-fledging seasons. I …

Fishing Top Predators Indirectly Affects Condition And Reproduction In A Reef-Fish Community, S.M. Walsh, S.L. Hamilton, Bi. Ruttenberg, M.K. Donovan, S.A. Sandin

Biological Sciences

To examine the indirect effects of fishing on energy allocation in non-target prey species, condition and reproductive potential were measured for five representative species (two-spot red snapper Lutjanus bohar, arc-eye hawkfish Paracirrhites arcatus, blackbar devil Plectroglyphidodon dickii, bicolour chromis Chromis margaritifer and whitecheek surgeonfish Acanthurus nigricans) from three reef-fish communities with different levels of fishing and predator abundance in the northern Line Islands, central Pacific Ocean. Predator abundance differed by five to seven-fold among islands, and despite no clear differences in prey abundance, differences in prey condition and reproductive potential among islands were found. Body condition …

Postdispersal Seed Predation Limits The Abundance Of A Long-Lived Perennial Forb (Lithospermum Ruderale), Mary Carolyn Bricker, John L. Maron

Biological Sciences Faculty Publications

Loss of seeds to consumers is common in plant communities, but the degree to which these losses influence plant abundance or population growth is often unclear. This is particularly the case for postdispersal seed predation by rodents, as most studies of rodent seed predation have focused on the sources of spatiotemporal variation in seed loss but not quantified the population consequences of this loss. In previous work we showed that seed predation by deer mice (Peromyscus maniculatus) substantially reduced seedling recruitment and establishment of Lithospermum ruderale (Boraginaceae), a long-lived perennial forb. To shed light on how rodent seed …

Species-Specific Relationship Between Transpiration And Cadmium Translocation In Lettuce, Barley And Radish, Mst. Fardausi Akhter, Sheila Macfie

Biology Publications

Cadmium (Cd) may accumulate in plants to levels that are of concern in human diets. Our ability to predict the accumulation of Cd in plants is restricted by our poor understanding of the physiological processes that control Cd accumulation and translocation. A hydroponic experiment was carried out to test the hypothesis that the amount of Cd taken up and translocated to aboveground tissues is proportional to the volume of water transpired in lettuce (Lactuca sativa L.), barley (Hordeum vulgare L.) and radish (Raphanus sativus L.). Transpiration was measured as mass of water lost. Increased transpiration caused increased accumulation of Cd …