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Evolutionary History Of Plant Hosts And Fungal Symbionts Predicts The Strength Of Mycorrhizal Mutualism, Jason D. Hoeksema, James D. Bever, Sounak Chakraborty, V. Bala Chaudhary, Monique Gardes, Catherine A. Gehring, Miranda M. Hart, Elizabeth A. Housworth, Wittaya Kaonongbua, Marc J. Lajeunesse Aug 2018

Evolutionary History Of Plant Hosts And Fungal Symbionts Predicts The Strength Of Mycorrhizal Mutualism, Jason D. Hoeksema, James D. Bever, Sounak Chakraborty, V. Bala Chaudhary, Monique Gardes, Catherine A. Gehring, Miranda M. Hart, Elizabeth A. Housworth, Wittaya Kaonongbua, Marc J. Lajeunesse

Integrative Biology Faculty and Staff Publications

Most plants engage in symbioses with mycorrhizal fungi in soils and net consequences for plants vary widely from mutualism to parasitism. However, we lack a synthetic understanding of the evolutionary and ecological forces driving such variation for this or any other nutritional symbiosis. We used meta-analysis across 646 combinations of plants and fungi to show that evolutionary history explains substantially more variation in plant responses to mycorrhizal fungi than the ecological factors included in this study, such as nutrient fertilization and additional microbes. Evolutionary history also has a different influence on outcomes of ectomycorrhizal versus arbuscular mycorrhizal symbioses; the former …


The Influence Of Landscape And Environmental Factors On Ranavirus Epidemiology In A California Amphibian Assemblage, Brian J. Tornabene, Andrew R. Blausten, Cheryl J. Briggs, Dana M. Calhoun, Pieter T. J. Johnson, Travis Mcdevitt-Galles, Jason R. Rohr, Jason T. Hoverman Jul 2018

The Influence Of Landscape And Environmental Factors On Ranavirus Epidemiology In A California Amphibian Assemblage, Brian J. Tornabene, Andrew R. Blausten, Cheryl J. Briggs, Dana M. Calhoun, Pieter T. J. Johnson, Travis Mcdevitt-Galles, Jason R. Rohr, Jason T. Hoverman

Integrative Biology Faculty and Staff Publications

  1. A fundamental goal of disease ecology is to determine the landscape and environmental processes that drive disease dynamics at different biological levels to guide management and conservation. Although ranaviruses (family Iridoviridae) are emerging amphibian pathogens, few studies have conducted comprehensive field surveys to assess potential drivers of ranavirus disease dynamics.
  2. We examined the factors underlying patterns in site‐level ranavirus presence and individual‐level ranavirus infection in 76 ponds and 1,088 individuals representing five amphibian species within the East Bay region of California.
  3. Based on a competing‐model approach followed by variance partitioning, landscape and biotic variables explained the most variation in …


Using Multi‐Response Models To Investigate Pathogen Coinfections Across Scales: Insights From Emerging Diseases Of Amphibians, William E. Stutz, Andrew R. Blaustein, Cheryl J. Briggs, Jason T. Hoverman, Jason R. Rohr, Pieter T. J. Johnson Apr 2018

Using Multi‐Response Models To Investigate Pathogen Coinfections Across Scales: Insights From Emerging Diseases Of Amphibians, William E. Stutz, Andrew R. Blaustein, Cheryl J. Briggs, Jason T. Hoverman, Jason R. Rohr, Pieter T. J. Johnson

Integrative Biology Faculty and Staff Publications

  1. Associations among parasites affect many aspects of host–parasite dynamics, but a lack of analytical tools has limited investigations of parasite correlations in observational data that are often nested across spatial and biological scales.
  2. Here we illustrate how hierarchical, multiresponse modelling can characterize parasite associations by allowing for hierarchical structuring, offering estimates of uncertainty and incorporating correlational model structures. After introducing the general approach, we apply this framework to investigate coinfections among four amphibian parasites (the trematodes Ribeiroia ondatrae and Echinostoma spp., the chytrid fungus Batrachochytrium dendrobatidis and ranaviruses) and among >2,000 individual hosts, 90 study sites and five amphibian host …


Do Host‐Associated Gut Microbiota Mediate The Effect Of An Herbicide On Disease Risk In Frogs?, Sarah A. Knutie, Caitlin R. Gabor, Kevin D. Kohl, Jason R. Rohr Mar 2018

Do Host‐Associated Gut Microbiota Mediate The Effect Of An Herbicide On Disease Risk In Frogs?, Sarah A. Knutie, Caitlin R. Gabor, Kevin D. Kohl, Jason R. Rohr

Integrative Biology Faculty and Staff Publications

  1. Environmental stressors, such as pollutants, can increase disease risk in wildlife. For example, the herbicide atrazine affects host defences (e.g. resistance and tolerance) of the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd), but the mechanisms for these associations are not entirely clear. Given that pollutants can alter the gut microbiota of hosts, which in turn can affect their health and immune systems, one potential mechanism by which pollutants could increase infection risk is by influencing host‐associated microbiota.
  2. Here, we test whether early‐life exposure to the estimated environmental concentration (EEC; 200 μg/L) of atrazine affects the gut bacterial composition of …


Agrochemicals Increase Risk Of Human Schistosomiasis By Supporting Higher Densities Of Intermediate Hosts, Neal T. Halstead, Christopher M. Hoover, Arathi Arakala, David J. Civitello, Guilio A. De Leo, Manoj Gambhir, Steve A. Johnson, Nicolas Jouanard, Kristin A. Loerns, Karena Nguyen, Jason R. Rohr Feb 2018

Agrochemicals Increase Risk Of Human Schistosomiasis By Supporting Higher Densities Of Intermediate Hosts, Neal T. Halstead, Christopher M. Hoover, Arathi Arakala, David J. Civitello, Guilio A. De Leo, Manoj Gambhir, Steve A. Johnson, Nicolas Jouanard, Kristin A. Loerns, Karena Nguyen, Jason R. Rohr

Integrative Biology Faculty and Staff Publications

Schistosomiasis is a snail-borne parasitic disease that ranks among the most important water-based diseases of humans in developing countries. Increased prevalence and spread of human schistosomiasis to non-endemic areas has been consistently linked with water resource management related to agricultural expansion. However, the role of agrochemical pollution in human schistosome transmission remains unexplored, despite strong evidence of agrochemicals increasing snail-borne diseases of wildlife and a projected 2- to 5-fold increase in global agrochemical use by 2050. Using a field mesocosm experiment, we show that environmentally relevant concentrations of fertilizer, a herbicide, and an insecticide, individually and as mixtures, increase densities …


Resilience In Moving Water: Effects Of Turbulence On The Predatory Impact Of The Lobate Ctenophore Mnemiopsis Leidyi, Cornelia Jaspers, John H. Costello, Kelly R. Sutherland, Brad J. Gemmell, Kelsey N. Lucas, Jennifer Tackett, Kara Dodge, Sean P. Colin Jan 2018

Resilience In Moving Water: Effects Of Turbulence On The Predatory Impact Of The Lobate Ctenophore Mnemiopsis Leidyi, Cornelia Jaspers, John H. Costello, Kelly R. Sutherland, Brad J. Gemmell, Kelsey N. Lucas, Jennifer Tackett, Kara Dodge, Sean P. Colin

Integrative Biology Faculty and Staff Publications

Despite its delicate morphology, the lobate ctenophore Mnemiopsis leidyi thrives in coastal ecosystems as an influential zooplankton predator. Coastal ecosystems are often characterized as energetic systems with high levels of natural turbulence in the water column. To understand how natural wind‐driven turbulence affects the feeding ecology of M. leidyi, we used a combination of approaches to quantify how naturally and laboratory generated turbulence affects the behavior, feeding processes and feeding impact of M. leidyi. Experiments using laboratory generated turbulence demonstrated that turbulence can reduce M. leidyi feeding rates on copepods and Artemia nauplii by > 50%. However, detailed feeding …


Author Correction: Evolutionary History Of Plant Hosts And Fungal Symbionts Predicts The Strength Of Mycorrhizal Mutualism, Jason D. Hoeksema, James D. Bever, Sounak Chakraborty, V. Bala Chaudhary, Monique Gardes, Catherine A. Gehring, Miranda M. Hart, Elizabeth A. Housworth, Wittaya Kaonongbua, Marc J. Lajeunesse Jan 2018

Author Correction: Evolutionary History Of Plant Hosts And Fungal Symbionts Predicts The Strength Of Mycorrhizal Mutualism, Jason D. Hoeksema, James D. Bever, Sounak Chakraborty, V. Bala Chaudhary, Monique Gardes, Catherine A. Gehring, Miranda M. Hart, Elizabeth A. Housworth, Wittaya Kaonongbua, Marc J. Lajeunesse

Integrative Biology Faculty and Staff Publications

In the original published version of the article, the description of the fixed-effect predictor Inoculum Complexity presented in the Methods was incorrect. The incorrect description given was: “single fungal genus, multiple fungal genera, or whole soil inoculum”. The correct description is: “single fungal species, multiple fungal species, or whole soil inoculum”. The error does not affect any of the results presented in the paper. The correction has been made to the HTML and PDF versions of the paper.


The Ecology And Economics Of Restoration: When, What, Where, And How To Restore Ecosystems, Jason R. Rohr, Emily S. Bernhardt, Marc W. Cadotte, William H. Clements Jan 2018

The Ecology And Economics Of Restoration: When, What, Where, And How To Restore Ecosystems, Jason R. Rohr, Emily S. Bernhardt, Marc W. Cadotte, William H. Clements

Integrative Biology Faculty and Staff Publications

Restoration ecology has provided a suite of tools for accelerating the recovery of ecosystems damaged by drivers of global change. We review both the ecological and economic concepts developed in restoration ecology, and offer guidance on when, what, where, and how to restore ecosystems. For when to restore, we highlight the value of pursuing restoration early to prevent ecosystems from crossing tipping points and evaluating whether unassisted natural recovery is more cost-effective than active restoration. For what to restore, we encourage developing a restoration plan with stakeholders that will restore structural, compositional, and functional endpoints, and whose goal is a …


A Faculty Professional Development Model That Improves Student Learning, Encourages Active-Learning Instructional Practices, And Works For Faculty At Multiple Institutions, Karen N. Pelletrau, Jennifer K. Knight, Paula P. Lemons, Jill S. Mccourt, John E, Merrill, Ross H. Nehm, Luanna B Prevost, Mark Urban-Lurain, Michelle K. Smith Jan 2018

A Faculty Professional Development Model That Improves Student Learning, Encourages Active-Learning Instructional Practices, And Works For Faculty At Multiple Institutions, Karen N. Pelletrau, Jennifer K. Knight, Paula P. Lemons, Jill S. Mccourt, John E, Merrill, Ross H. Nehm, Luanna B Prevost, Mark Urban-Lurain, Michelle K. Smith

Integrative Biology Faculty and Staff Publications

Helping faculty develop high-quality instruction that positively affects student learning can be complicated by time limitations, a lack of resources, and inexperience using student data to make iterative improvements. We describe a community of 16 faculty from five institutions who overcame these challenges and collaboratively designed, taught, iteratively revised, and published an instructional unit about the potential effect of mutations on DNA replication, transcription, and translation. The unit was taught to more than 2000 students in 18 courses, and student performance improved from preassessment to postassessment in every classroom. This increase occurred even though faculty varied in their instructional practices …


Genetic And Epigenetic Variation In Spartina Alterniflora Following The Deepwater Horizon Oil Spill, Marta Robertson, Aaron Schrey, Ashley Shayter, Christina J. Moss, Christina Richards Jan 2017

Genetic And Epigenetic Variation In Spartina Alterniflora Following The Deepwater Horizon Oil Spill, Marta Robertson, Aaron Schrey, Ashley Shayter, Christina J. Moss, Christina Richards

Integrative Biology Faculty and Staff Publications

Catastrophic events offer unique opportunities to study rapid population response to stress in natural settings. In concert with genetic variation, epigenetic mechanisms may allow populations to persist through severe environmental challenges. In 2010, the Deepwater Horizon oil spill devastated large portions of the coastline along the Gulf of Mexico. However, the foundational salt marsh grass, Spartina alterniflora, showed high resilience to this strong environmental disturbance. Following the spill, we simultaneously examined the genetic and epigenetic structure of recovering populations of S. alterniflora to oil exposure. We quantified genetic and DNA methylation variation using amplified fragment length polymorphism and methylation …


Suitability Of Laurentian Great Lakes For Invasive Species Based On Global Species Distribution Models And Local Habitat, Andrew M. Kramer, Gust Annis, Marion E. Wittmann, William L. Chadderton, Edward S. Rutherford, David M. Lodge, Lacey Mason, Dmitry Beletsky, Catherine Riseng, John M. Drake Jan 2017

Suitability Of Laurentian Great Lakes For Invasive Species Based On Global Species Distribution Models And Local Habitat, Andrew M. Kramer, Gust Annis, Marion E. Wittmann, William L. Chadderton, Edward S. Rutherford, David M. Lodge, Lacey Mason, Dmitry Beletsky, Catherine Riseng, John M. Drake

Integrative Biology Faculty and Staff Publications

Efficient management and prevention of species invasions requires accurate prediction of where species of concern can arrive and persist. Species distribution models provide one way to identify potentially suitable habitat by developing the relationship between climate variables and species occurrence data. However, these models when applied to freshwater invasions are complicated by two factors. The first is that the range expansions that typically occur as part of the invasion process violate standard species distribution model assumptions of data stationarity. Second, predicting potential range of freshwater aquatic species is complicated by the reliance on terrestrial climate measurements to develop occurrence relationships …


Microbe Biogeography Tracks Water Masses In A Dynamic Oceanic Frontal System, Anni Djurhuus, Philipp H. Boersch-Supan, Svein-Ole Mikalse, Alex D. Rogers Jan 2017

Microbe Biogeography Tracks Water Masses In A Dynamic Oceanic Frontal System, Anni Djurhuus, Philipp H. Boersch-Supan, Svein-Ole Mikalse, Alex D. Rogers

Integrative Biology Faculty and Staff Publications

Dispersal limitation, not just environmental selection, plays an important role in microbial biogeography. The distance–decay relationship is thought to be weak in habitats where dispersal is high, such as in the pelagic environment, where ocean currents facilitate microbial dispersal. Most studies of microbial community composition to date have observed little geographical heterogeneity on a regional scale (100 km). We present a study of microbial communities across a dynamic frontal zone in the southwest Indian Ocean and investigate the spatial structure of the microbes with respect to the different water masses separated by these fronts. We collected 153 samples of free-living …


Accuracy Of Climate-Based Forecasts Of Pathogen Spread, Annakate M. Schatz, Andrew M. Kramer, John M. Drake Jan 2017

Accuracy Of Climate-Based Forecasts Of Pathogen Spread, Annakate M. Schatz, Andrew M. Kramer, John M. Drake

Integrative Biology Faculty and Staff Publications

Species distribution models (SDMs) are a tool for predicting the eventual geographical range of an emerging pathogen. Most SDMs, however, rely on an assumption of equilibrium with the environment, which an emerging pathogen, by definition, has not reached. To determine if some SDM approaches work better than others for modelling the spread of emerging, non-equilibrium pathogens, we studied time-sensitive predictive performance of SDMs for Batrachochytrium dendrobatidis, a devastating infectious fungus of amphibians, using multiple methods trained on time-incremented subsets of the available data. We split our data into timeline-based training and testing sets, and evaluated models on each set …


Changing Measurements Or Changing Movements? Sampling Scale And Movement Model Identifiability Across Generations Of Biologging Technology, Leah R. Johnson, Philipp H. Boersch-Supan, Richard A. Phillips, Sadie J. Ryan Jan 2017

Changing Measurements Or Changing Movements? Sampling Scale And Movement Model Identifiability Across Generations Of Biologging Technology, Leah R. Johnson, Philipp H. Boersch-Supan, Richard A. Phillips, Sadie J. Ryan

Integrative Biology Faculty and Staff Publications

Animal movement patterns contribute to our understanding of variation in breeding success and survival of individuals, and the implications for population dynamics. Over time, sensor technology for measuring movement patterns has improved. Although older technologies may be rendered obsolete, the existing data are still valuable, especially if new and old data can be compared to test whether a behavior has changed over time. We used simulated data to assess the ability to quantify and correctly identify patterns of seabird flight lengths under observational regimes used in successive generations of wet/dry logging technology. Care must be taken when comparing data collected …


Analyzing And Modeling The Dysfunction Of Inhibitory Neurons In Alzheimer’S Disease, Carlos Perez, Jokubas Ziburkus, Ghamim Ullah Dec 2016

Analyzing And Modeling The Dysfunction Of Inhibitory Neurons In Alzheimer’S Disease, Carlos Perez, Jokubas Ziburkus, Ghamim Ullah

Physics Faculty Publications

Alzheimer’s disease (AD) is characterized by the abnormal proteolytic processing of amyloid precursor protein, resulting in increased production of a self-aggregating form of beta amyloid (Aβ). Several lines of work on AD patients and transgenic mice with high Aβ levels exhibit altered rhythmicity, aberrant neuronal network activity and hyperexcitability reflected in clusters of hyperactive neurons, and spontaneous epileptic activity. Recent studies highlight that abnormal accumulation of Aβ changes intrinsic properties of inhibitory neurons, which is one of the main reasons underlying the impaired network activity. However, specific cellular mechanisms leading to interneuronal dysfunction are not completely …


Molecular Typing And Virulence Analysis Of Multidrug Resistant Klebsiella Pneumoniae Clinical Isolates Recovered From Egyptian Hospitals, Reham Wasfi, Walid F. Elkhatib, Hossam M. Ashour Dec 2016

Molecular Typing And Virulence Analysis Of Multidrug Resistant Klebsiella Pneumoniae Clinical Isolates Recovered From Egyptian Hospitals, Reham Wasfi, Walid F. Elkhatib, Hossam M. Ashour

Molecular Biosciences Faculty Publications

Klebsiella pneumonia infection rates have increased dramatically. Molecular typing and virulence analysis are powerful tools that can shed light on Klebsiella pneumonia infections. Whereas 77.7% (28/36) of clinical isolates indicated multidrug resistant (MDR) patterns, 50% (18/36) indicated carpabenem resistance. Gene prevalence for the AcrAB efflux pump (82.14%) was more than that of the mdtK efflux pump (32.14%) in the MDR isolates. FimH-1 and mrkD genes were prevalent in wound and blood isolates. FimH-1 gene was prevalent in sputum while mrkD gene was prevalent in urine. Serum resistance associated with outer membrane protein coding gene (traT) was found in all blood …


Recurring Patterns Among Scrambled Genes In The Encrypted Genome Of The Ciliate Oxytricha Trifallax, Jonathan Burns, Denys Kukushkin, Xiao Chen, Laura F Landweber, Masahico Saito, Nataša Jonoska Dec 2016

Recurring Patterns Among Scrambled Genes In The Encrypted Genome Of The Ciliate Oxytricha Trifallax, Jonathan Burns, Denys Kukushkin, Xiao Chen, Laura F Landweber, Masahico Saito, Nataša Jonoska

Mathematics and Statistics Faculty Publications

Some genera of ciliates, such as Oxytricha and Stylonychia, undergo massive genome reorganization during development and provide model organisms to study DNA rearrangement. A common feature of these ciliates is the presence of two types of nuclei: a germline micronucleus and a transcriptionally-active somatic macronucleus containing over 16,000 gene sized "nano-chromosomes". During conjugation the old parental macronucleus disintegrates and a new macronucleus forms from a copy of the zygotic micronucleus. During this process, macronuclear chromosomes assemble through DNA processing events that delete 90-98% of the DNA content of the micronucleus. This includes the deletion of noncoding DNA segments that interrupt …


A Novel Rrm3 Function In Restricting Dna Replication Via An Orc5-Binding Domain Is Genetically Separable From Rrm3 Function As An Atpase/Helicase In Facilitating Fork Progression, Salahuddin Syed, Claus Desler, Lene J Rasmussen, Kristina H Schmidt Dec 2016

A Novel Rrm3 Function In Restricting Dna Replication Via An Orc5-Binding Domain Is Genetically Separable From Rrm3 Function As An Atpase/Helicase In Facilitating Fork Progression, Salahuddin Syed, Claus Desler, Lene J Rasmussen, Kristina H Schmidt

Molecular Biosciences Faculty Publications

In response to replication stress cells activate the intra-S checkpoint, induce DNA repair pathways, increase nucleotide levels, and inhibit origin firing. Here, we report that Rrm3 associates with a subset of replication origins and controls DNA synthesis during replication stress. The N-terminal domain required for control of DNA synthesis maps to residues 186-212 that are also critical for binding Orc5 of the origin recognition complex. Deletion of this domain is lethal to cells lacking the replication checkpoint mediator Mrc1 and leads to mutations upon exposure to the replication stressor hydroxyurea. This novel Rrm3 function is independent of its established role …


Step By Step: Biology Undergraduates' Problem-Solving Procedures During Multiple-Choice Assessment, Luanna B Prevost, Paula P Lemons Dec 2016

Step By Step: Biology Undergraduates' Problem-Solving Procedures During Multiple-Choice Assessment, Luanna B Prevost, Paula P Lemons

Integrative Biology Faculty and Staff Publications

This study uses the theoretical framework of domain-specific problem solving to explore the procedures students use to solve multiple-choice problems about biology concepts. We designed several multiple-choice problems and administered them on four exams. We trained students to produce written descriptions of how they solved the problem, and this allowed us to systematically investigate their problem-solving procedures. We identified a range of procedures and organized them as domain general, domain specific, or hybrid. We also identified domain-general and domain-specific errors made by students during problem solving. We found that students use domain-general and hybrid procedures more frequently when solving lower-order …


Reintroducing Environmental Change Drivers In Biodiversity-Ecosystem Functioning Research., Frederik De Laender, Jason R. Rohr, Roman Ashauer, Donald J Baird, Uta Berger, Nico Eisenhauer, Volker Grimm, Udo Hommen, Lorraine Maltby, Carlos J Meliàn Dec 2016

Reintroducing Environmental Change Drivers In Biodiversity-Ecosystem Functioning Research., Frederik De Laender, Jason R. Rohr, Roman Ashauer, Donald J Baird, Uta Berger, Nico Eisenhauer, Volker Grimm, Udo Hommen, Lorraine Maltby, Carlos J Meliàn

Integrative Biology Faculty and Staff Publications

For the past 20 years, research on biodiversity and ecosystem functioning (B-EF) has only implicitly considered the underlying role of environmental change. We illustrate that explicitly reintroducing environmental change drivers in B-EF research is needed to predict the functioning of ecosystems facing changes in biodiversity. Next we show how this reintroduction improves experimental control over community composition and structure, which helps to provide mechanistic insight on how multiple aspects of biodiversity relate to function and how biodiversity and function relate in food webs. We also highlight challenges for the proposed reintroduction and suggest analyses and experiments to better understand how …


Quantitative Proteomic Profiling Reveals Hepatic Lipogenesis And Liver X Receptor Activation In The Pander Transgenic Model., Mark G. Athanason, Whitney A. Ratliff, Dale Chaput, Catherine B. Marelia, Melanie N. Kuehl, Stanley M. Stevens Jr., Brant R. Burkhardt Nov 2016

Quantitative Proteomic Profiling Reveals Hepatic Lipogenesis And Liver X Receptor Activation In The Pander Transgenic Model., Mark G. Athanason, Whitney A. Ratliff, Dale Chaput, Catherine B. Marelia, Melanie N. Kuehl, Stanley M. Stevens Jr., Brant R. Burkhardt

Molecular Biosciences Faculty Publications

PANcreatic-DERived factor (PANDER) is a member of a superfamily of FAM3 proteins modulating glycemic levels by metabolic regulation of the liver and pancreas. The precise PANDER-induced hepatic signaling mechanism is still being elucidated and has been very complex due to the pleiotropic nature of this novel hormone. Our PANDER transgenic (PANTG) mouse displays a selective hepatic insulin resistant (SHIR) phenotype whereby insulin signaling is blunted yet lipogenesis is increased, a phenomena observed in type 2 diabetes. To examine the complex PANDER-induced mechanism of SHIR, we utilized quantitative mass spectrometry-based proteomic analysis using Stable Isotope Labeling by Amino Acids in Cell …


Mathematical Models Are A Powerful Method To Understand And Control The Spread Of Huanglongbing, Rachel A Taylor, Erin A Mordecai, Christopher A Gilligan, Jason R. Rohr, Leah R Johnson Nov 2016

Mathematical Models Are A Powerful Method To Understand And Control The Spread Of Huanglongbing, Rachel A Taylor, Erin A Mordecai, Christopher A Gilligan, Jason R. Rohr, Leah R Johnson

Integrative Biology Faculty and Staff Publications

Huanglongbing (HLB), or citrus greening, is a global citrus disease occurring in almost all citrus growing regions. It causes substantial economic burdens to individual growers, citrus industries and governments. Successful management strategies to reduce disease burden are desperately needed but with so many possible interventions and combinations thereof it is difficult to know which are worthwhile or cost-effective. We review how mathematical models have yielded useful insights into controlling disease spread for other vector-borne plant diseases, and the small number of mathematical models of HLB. We adapt a malaria model to HLB, by including temperature-dependent psyllid traits, "flushing" of trees, …


Human-Associated Bacteroides Spp. And Human Polyomaviruses As Microbial Source Tracking Markers In Hawaii, Marek Kirs, Roberto A Caffaro-Filho, Mayee Wong, Valerie J. Harwood, Philip Moravcik, Roger S Fujioka Nov 2016

Human-Associated Bacteroides Spp. And Human Polyomaviruses As Microbial Source Tracking Markers In Hawaii, Marek Kirs, Roberto A Caffaro-Filho, Mayee Wong, Valerie J. Harwood, Philip Moravcik, Roger S Fujioka

Integrative Biology Faculty and Staff Publications

Identification of sources of fecal contaminants is needed to (i) determine the health risk associated with recreational water use and (ii) implement appropriate management practices to mitigate this risk and protect the environment. This study evaluated human-associated Bacteroides spp. (HF183TaqMan) and human polyomavirus (HPyV) markers for host sensitivity and specificity using human and animal fecal samples collected in Hawaii. The decay rates of those markers and indicator bacteria were identified in marine and freshwater microcosms exposed and not exposed to sunlight, followed by field testing of the usability of the molecular markers. Both markers were strongly associated with sewage, although …


Subcellular And In-Vivo Nano-Endoscopy, Surya Venkatasekhar Cheemalapati, John Winskas, Hao Wang, Karthik Konnaiyan, Arseny Zhdanov, Alison Roth, Swamy Rakesh Adapa, Andrew Deonarine, Rays H. Y. Jiang, Anna Pyayt Oct 2016

Subcellular And In-Vivo Nano-Endoscopy, Surya Venkatasekhar Cheemalapati, John Winskas, Hao Wang, Karthik Konnaiyan, Arseny Zhdanov, Alison Roth, Swamy Rakesh Adapa, Andrew Deonarine, Rays H. Y. Jiang, Anna Pyayt

Chemical, Biological and Materials Engineering Faculty Publications

Analysis of individual cells at the subcellular level is important for understanding diseases and accelerating drug discovery. Nanoscale endoscopes allow minimally invasive probing of individual cell interiors. Several such instruments have been presented previously, but they are either too complex to fabricate or require sophisticated external detectors because of low signal collection efficiency. Here we present a nanoendoscope that can locally excite fluorescence in labelled cell organelles and collect the emitted signal for spectral analysis. Finite Difference Time Domain (FDTD) simulations have shown that with an optimized nanoendoscope taper profile, the light emission and collection was localized within ~100 nm. …


Staphylococcus Aureus Coordinates Leukocidin Expression And Pathogenesis By Sensing Metabolic Fluxes Via Rpirc, Divya Balasubramanian, Elizabeth A Ohneck, Jessica Chapman, Andy Weiss, Min Kyung Kim, Tamara Reyes-Robles, Judy Zhong, Lindsey N. Shaw, Desmond S. Lun, Beatrix Ueberheide, Bo Shopsin, Victor J Torres Jun 2016

Staphylococcus Aureus Coordinates Leukocidin Expression And Pathogenesis By Sensing Metabolic Fluxes Via Rpirc, Divya Balasubramanian, Elizabeth A Ohneck, Jessica Chapman, Andy Weiss, Min Kyung Kim, Tamara Reyes-Robles, Judy Zhong, Lindsey N. Shaw, Desmond S. Lun, Beatrix Ueberheide, Bo Shopsin, Victor J Torres

Molecular Biosciences Faculty Publications

Staphylococcus aureus is a formidable human pathogen that uses secreted cytolytic factors to injure immune cells and promote infection of its host. Of these proteins, the bicomponent family of pore-forming leukocidins play critical roles in S. aureus pathogenesis. The regulatory mechanisms governing the expression of these toxins are incompletely defined. In this work, we performed a screen to identify transcriptional regulators involved in leukocidin expression in S. aureus strain USA300. We discovered that a metabolic sensor-regulator, RpiRc, is a potent and selective repressor of two leukocidins, LukED and LukSF-PV. Whole-genome transcriptomics, S. aureus exoprotein proteomics, and metabolomic analyses revealed that …


Home-Field Advantage? Evidence Of Local Adaptation Among Plants, Soil, And Arbuscular Mycorrhizal Fungi Through Meta-Analysis, Megan A. Rúa, Anita Antoninka, Pedro M. Antunes, V Bala Chaudhary, Catherine Gehring, Louis J. Lamit, Bridget J. Piculell, James D. Bever, Cathy Zabinski, James F. Meadow, Marc J. Lajeunesse, Brook G. Milligan, Justine Karst, Jason D. Hoeksema Jun 2016

Home-Field Advantage? Evidence Of Local Adaptation Among Plants, Soil, And Arbuscular Mycorrhizal Fungi Through Meta-Analysis, Megan A. Rúa, Anita Antoninka, Pedro M. Antunes, V Bala Chaudhary, Catherine Gehring, Louis J. Lamit, Bridget J. Piculell, James D. Bever, Cathy Zabinski, James F. Meadow, Marc J. Lajeunesse, Brook G. Milligan, Justine Karst, Jason D. Hoeksema

Integrative Biology Faculty and Staff Publications

BACKGROUND: Local adaptation, the differential success of genotypes in their native versus foreign environment, arises from various evolutionary processes, but the importance of concurrent abiotic and biotic factors as drivers of local adaptation has only recently been investigated. Local adaptation to biotic interactions may be particularly important for plants, as they associate with microbial symbionts that can significantly affect their fitness and may enable rapid evolution. The arbuscular mycorrhizal (AM) symbiosis is ideal for investigations of local adaptation because it is globally widespread among most plant taxa and can significantly affect plant growth and fitness. Using meta-analysis on 1170 studies …


Current Status Of Marker Genes Of Bacteroides And Related Taxa For Identifying Sewage Pollution In Environmental Waters, Warish Ahmed, Bridie Hughes, Valerie J. Harwood May 2016

Current Status Of Marker Genes Of Bacteroides And Related Taxa For Identifying Sewage Pollution In Environmental Waters, Warish Ahmed, Bridie Hughes, Valerie J. Harwood

Integrative Biology Faculty and Staff Publications

Microbial source tracking (MST) endeavors to determine sources of fecal pollution in environmental waters by capitalizing on the association of certain microorganisms with the gastrointestinal tract and feces of specific animal groups. Several decades of research have shown that bacteria belonging to the gut-associated order Bacteroidales, and particularly the genus Bacteroides, tend to co-evolve with the host, and are, therefore, particularly suitable candidates for MST applications. This review summarizes the current research on MST methods that employ genes belonging to Bacteroidales/Bacteroides as tracers or “markers” of sewage pollution, including known advantages and deficiencies of the many polymerase chain …


Characterization Of A Silac Method For Proteomic Analysis Of Primary Rat Microglia, Ping Zhang, Ashley E. Culver-Cochran, Stanley M. Stevens Jr., Bin Liu May 2016

Characterization Of A Silac Method For Proteomic Analysis Of Primary Rat Microglia, Ping Zhang, Ashley E. Culver-Cochran, Stanley M. Stevens Jr., Bin Liu

Molecular Biosciences Faculty Publications

Microglia play important and dynamic roles in mediating a variety of physiological and pathological processes during the development, normal function and degeneration of the central nervous system. Application of SILAC-based proteomic analysis would greatly facilitate the identification of cellular pathways regulating the multifaceted phenotypes of microglia. We and others have successfully SILAC-labeled immortalized murine microglial cell lines in previous studies. In this study, we report the development and evaluation of a SILAC-labeled primary rat microglia model. Although the isotope labeling scheme for primary microglia is drastically different from that of immortalized cell lines, our de novo and uninterrupted primary culture …


Transforming Ecosystems: When, Where, And How To Restore Contaminated Sites, Jason R. Rohr, Aïda M. Farag, Marc W. Cadotte, William H. Clements, James R. Smith, Cheryl P. Ulrich, Richard Woods Apr 2016

Transforming Ecosystems: When, Where, And How To Restore Contaminated Sites, Jason R. Rohr, Aïda M. Farag, Marc W. Cadotte, William H. Clements, James R. Smith, Cheryl P. Ulrich, Richard Woods

Integrative Biology Faculty and Staff Publications

Chemical contamination has impaired ecosystems, reducing biodiversity and the provisioning of functions and services. This has spurred a movement to restore contaminated ecosystems and develop and implement national and international regulations that require it. Nevertheless, ecological restoration remains a young and rapidly growing discipline and its intersection with toxicology is even more nascent and underdeveloped. Consequently, we provide guidance to scientists and practitioners on when, where, and how to restore contaminated ecosystems. Although restoration has many benefits, it also can be expensive, and in many cases systems can recover without human intervention. Hence, the first question we address is: "When …


Hunting, Food Subsidies, And Mesopredator Release: The Dynamics Of Crop-Raiding Baboons In A Managed Landscape, Rachel A. Taylor, Sadie J. Ryan, Justin S. Brashares, Leah R. Johnson Apr 2016

Hunting, Food Subsidies, And Mesopredator Release: The Dynamics Of Crop-Raiding Baboons In A Managed Landscape, Rachel A. Taylor, Sadie J. Ryan, Justin S. Brashares, Leah R. Johnson

Integrative Biology Faculty and Staff Publications

The establishment of protected areas or parks has become an important tool for wildlife conservation. However, frequent occurrences of human-wildlife conflict at the edges of these parks can undermine their conservation goals. Many African protected areas have experienced concurrent declines of apex predators alongside increases in both baboon abundance and the density of humans living near the park boundary. Baboons then take excursions outside of the park to raid crops for food, conflicting with the human population. We model the interactions of mesopredators (baboons), apex predators, and shared prey in the park to analyze how four components affect the proportion …