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Biology Faculty Publications and Presentations

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Full-Text Articles in Biology

New World Origins Of Southwest Pacific Gesneriaceae: Multiple Movements Across And Within The South Pacific, Vincent L. Woo, Minde M. Funke, James F. Smith, Peter J. Lockhart, Philip J. Garnock-Jones Mar 2011

New World Origins Of Southwest Pacific Gesneriaceae: Multiple Movements Across And Within The South Pacific, Vincent L. Woo, Minde M. Funke, James F. Smith, Peter J. Lockhart, Philip J. Garnock-Jones

Biology Faculty Publications and Presentations

Coronanthereae is a tribe of ~20 species with a suite of unique morphological characters and a disjunct geographic distribution in the Southern Hemisphere. Three species are found in southern South America and the remainder in the southwest Pacific. It has been suggested, because of this distribution and disjunction, that Coronanthereae represents a relictual Gondwanan group from which the two major lineages in the family, the Old World Cyrtandroideae and the New World Gesnerioideae, originated. We tested this hypothesis by using phylogenetic analyses of nuclear and chloroplast DNA sequences, ancestral-area reconstruction, and molecular dating. The tribe is placed within the mostly …


New Implications On Genomic Adaptation Derived From The Helicobacter Pylori Genome Comparison, Edgar Eduardo Lara-Ramírez, Aldo Segura-Cabrera, Xianwu Guo, Gongxin Yu, Carlos Armando García-Pérez, Mario A. Rodríguez-Pérez Feb 2011

New Implications On Genomic Adaptation Derived From The Helicobacter Pylori Genome Comparison, Edgar Eduardo Lara-Ramírez, Aldo Segura-Cabrera, Xianwu Guo, Gongxin Yu, Carlos Armando García-Pérez, Mario A. Rodríguez-Pérez

Biology Faculty Publications and Presentations

Background: Helicobacter pylori has a reduced genome and lives in a tough environment for long-term persistence. It evolved with its particular characteristics for biological adaptation. Because several H. pylori genome sequences are available, comparative analysis could help to better understand genomic adaptation of this particular bacterium.

Principal Findings: We analyzed nine H. pylori genomes with emphasis on microevolution from a different perspective. Inversion was an important factor to shape the genome structure. Illegitimate recombination not only led to genomic inversion but also inverted fragment duplication, both of which contributed to the creation of new genes and gene family, and further, …


Migration Patterns, Use Of Stopover Areas, And Austral Summer Movements Of Swainson's Hawks, Michael N. Kochert, Mark R. Fuller, Linda S. Schueck, Laura Bond, Marc J. Bechard, Brian Woodbridge, Geoff L. Holroyd, Mark S. Martell, Ursula Banasch Feb 2011

Migration Patterns, Use Of Stopover Areas, And Austral Summer Movements Of Swainson's Hawks, Michael N. Kochert, Mark R. Fuller, Linda S. Schueck, Laura Bond, Marc J. Bechard, Brian Woodbridge, Geoff L. Holroyd, Mark S. Martell, Ursula Banasch

Biology Faculty Publications and Presentations

From 1995 to 1998, we tracked movements of adult Swainson’s Hawks (Buteo swainsoni), using satellite telemetry to characterize migration, important stopover areas, and movements in the austral summer. We tagged 46 hawks from July to September on their nesting grounds in seven U.S. states and two Canadian provinces. Swainson’s Hawks followed three basic routes south on a broad front, converged along the east coast of central Mexico, and followed a concentrated corridor to a communal area in central Argentina for the austral summer. North of 20°N, southward and northward tracks differed little for individuals from east of the …


Age Determination Of The Glassy-Winged Sharpshooter, Homalodisca Vitripennis, Using Wing Pigmentation, Chris Timmons, Aaron Hassell, Isabelle Lauziere, Blake Bextine Jan 2011

Age Determination Of The Glassy-Winged Sharpshooter, Homalodisca Vitripennis, Using Wing Pigmentation, Chris Timmons, Aaron Hassell, Isabelle Lauziere, Blake Bextine

Biology Faculty Publications and Presentations

A red pigment is contained in the wing veins of the glassy-winged sharpshooter, Homalodisca vitripennis (Hemiptera: Cicadellidae). This insect is the main vector of the plant-pathogenic bacterium Xylella fastidiosa Wells (Xanthomonadales: Xanthomonadaceae), the causal agent of Pierce's disease of grapevines. Over the course of the H. vitripennis lifespan, the red pigment darkens and eventually becomes brown/black in color. These pigments are believed to be pheomelanin and eumelanin, respectively. The age of H. vitripennis can be determined by calculating the amount of red pigment found in the wings by analyzing high resolution wing photographs with image analysis software. In this study, …


Escherichia Coli Fpg Glycosylase Is Nonrendundant And Required For The Rapid Global Repair Of Oxidized Purine And Pyrimidine Damage In Vivo, Brandy J. Schalow, Charmain T. Courcelle, Justin Courcelle Jan 2011

Escherichia Coli Fpg Glycosylase Is Nonrendundant And Required For The Rapid Global Repair Of Oxidized Purine And Pyrimidine Damage In Vivo, Brandy J. Schalow, Charmain T. Courcelle, Justin Courcelle

Biology Faculty Publications and Presentations

Endonuclease (Endo) III and formamidopyrimidine-N-glycosylase (Fpg) are two of the predominant DNA glycosylases in Escherichia coli that remove oxidative base damage. In cell extracts and purified form, Endo III is generally more active toward oxidized pyrimidines, while Fpg is more active towards oxidized purines. However, the substrate specificities of these enzymes partially overlap in vitro. Less is known about the relative contribution of these enzymes in restoring the genomic template following oxidative damage. In this study, we examined how efficiently Endo III and Fpg repair their oxidative substrates in vivo following treatment with hydrogen peroxide. We found …


Natural Variation In Life History And Aging Phenotypes Is Associated With Mitochondrial Dna Deletion Frequency In Caenorhabditis Briggsae, Suzanne Estes, Anna Luella Coleman-Hulbert, Kiley Ann Hicks, Gene De Haan, Sarah R. Martha, Jeremiah B. Knapp, Samson William Smith, Kevin C. Stein, Dee R. Denver Jan 2011

Natural Variation In Life History And Aging Phenotypes Is Associated With Mitochondrial Dna Deletion Frequency In Caenorhabditis Briggsae, Suzanne Estes, Anna Luella Coleman-Hulbert, Kiley Ann Hicks, Gene De Haan, Sarah R. Martha, Jeremiah B. Knapp, Samson William Smith, Kevin C. Stein, Dee R. Denver

Biology Faculty Publications and Presentations

Background: Mutations that impair mitochondrial functioning are associated with a variety of metabolic and age-related disorders. A barrier to rigorous tests of the role of mitochondrial dysfunction in aging processes has been the lack of model systems with relevant, naturally occurring mitochondrial genetic variation. Toward the goal of developing such a model system, we studied natural variation in life history, metabolic, and aging phenotypes as it relates to levels of a naturally-occurring heteroplasmic mitochondrial ND5 deletion recently discovered to segregate among wild populations of the soil nematode, Caenorhabditis briggsae. The normal product of ND5 is a central component of the …


Genome-Wide Detection Of Novel Regulatory Rnas In E. Coli, Rahul Raghavan, Eduardo Groisman, Howard Ochman Jan 2011

Genome-Wide Detection Of Novel Regulatory Rnas In E. Coli, Rahul Raghavan, Eduardo Groisman, Howard Ochman

Biology Faculty Publications and Presentations

The intergenic regions in bacterial genomes can contain regulatory leader sequences and small RNAs (sRNAs), which both serve to modulate gene expression. Computational analyses have predicted the presence of hundreds of these noncoding regulatory RNAs in Escherichia coli; however, only about 80 have been experimentally validated. By applying a deep-sequencing approach, we detected and quantified the vast majority of the previously validated regulatory elements and identified 10 new sRNAs and nine new regulatory leader sequences in the intergenic regions of E. coli. Half of the newly discovered sRNAs displayed enhanced stability in the presence of the RNA-binding protein …


Labile Soil Carbon Inputs Mediate The Soil Microbial Community Composition And Plant Residue Decomposition Rates, Marie-Anne De Graaff, Aimee T. Classen, Hector F. Castro, Christopher W. Schadt Dec 2010

Labile Soil Carbon Inputs Mediate The Soil Microbial Community Composition And Plant Residue Decomposition Rates, Marie-Anne De Graaff, Aimee T. Classen, Hector F. Castro, Christopher W. Schadt

Biology Faculty Publications and Presentations

• Root carbon (C) inputs may regulate decomposition rates in soil, and in this study we ask: how do labile C inputs regulate decomposition of plant residues, and soil microbial communities?

• In a 14 d laboratory incubation, we added C compounds often found in root exudates in seven different concentrations (0, 0.7, 1.4, 3.6, 7.2, 14.4 and 21.7 mg C g soil) to soils amended with and without 13C-labeled plant residue. We measured CO2 respiration and shifts in relative fungal and bacterial rRNA gene copy numbers using quantitative polymerase chain reaction (qPCR).

• Increased labile C input …


A Comparison Of Cumulative-Germination Response Of Cheatgrass (Bromus Tectorum L.) And Five Perennial Bunchgrass Species To Simulated Field-Temperature Regimes, Stuart P. Hardegree, Corey A. Moffet, Bruce A. Roundy, Thomas A. Jones, Stephen J. Novak, Patrick E. Clark, Frederick B. Pierson, Gerald N. Flerchinger Dec 2010

A Comparison Of Cumulative-Germination Response Of Cheatgrass (Bromus Tectorum L.) And Five Perennial Bunchgrass Species To Simulated Field-Temperature Regimes, Stuart P. Hardegree, Corey A. Moffet, Bruce A. Roundy, Thomas A. Jones, Stephen J. Novak, Patrick E. Clark, Frederick B. Pierson, Gerald N. Flerchinger

Biology Faculty Publications and Presentations

Cheatgrass (Bromus tectorum L.) has come to dominate millions of hectares of rangeland in the Intermountain western United States. Previous studies have hypothesized that one mechanism conferring a competitive advantage to this species is the ability to germinate rapidly at low temperatures in the fall, winter and spring and, therefore, initiate growth and establishment more rapidly than more desirable perennial bunchgrass species. In this experiment, we developed thermal-germination-response models for multiple seedlots of cheatgrass and five perennial grass species. We conducted sensitivity analysis on potentialcumulative- germination response to a 38-y simulation of field-variable conditions of seedbed temperature and moisture. …


Eighteen Microsatellite Loci Developed From Western Burrowing Owls (Athene Cunicularia Hypugaea), Brant C. Faircloth, Alexandra Title, Kevin Tan, Justin Welty, James R. Belthoff, Patricia Adair Gowaty Dec 2010

Eighteen Microsatellite Loci Developed From Western Burrowing Owls (Athene Cunicularia Hypugaea), Brant C. Faircloth, Alexandra Title, Kevin Tan, Justin Welty, James R. Belthoff, Patricia Adair Gowaty

Biology Faculty Publications and Presentations

Western burrowing owls (Athene cunicularia hypugaea) are ground-dwelling owls distributed throughout western North America. Because of population declines, this species is considered endangered in Canada, and burrowing owls are listed as a species of conservation concern in states of the western USA. Korfanta et al. (2002) previously presented primers for seven microsatellite loci in burrowing owls. Parentage and relatedness studies require a larger number of markers for accuracy and precision. Here, we developed and characterized 18 additional microsatellite DNA loci, and we tested these loci in 23 individuals. The number of alleles per locus ranged from 2 to …


The Role Of Caspases In Alzheimer's Disease; Potential Novel Therapeutic Opportunities, Troy T. Rohn Nov 2010

The Role Of Caspases In Alzheimer's Disease; Potential Novel Therapeutic Opportunities, Troy T. Rohn

Biology Faculty Publications and Presentations

Although apoptosis plays a critical role in molding the CNS into its final appearance and function, inappropriate activation of this pathway in the aging brain may contribute to neurodegeneration. In Alzheimer’s disease (AD), an overwhelming body of evidence supports the activation of apoptosis in general, and caspases specifically as an early event that may not only contribute to neurodegeneration but also promote the underlying pathology associated with this disease. Therefore, caspase inhibitors may provide an effective strategy for treating AD. However, despite the compelling evidence indicating a role for caspases in disease progression, chronic treatment with caspase inhibitors in animal …


Non-Native Salmonids Affect Amphibian Occupancy At Multiple Spatial Scales, David S. Pilliod, Blake R. Hossack, Peter F. Bahls, Evelyn L. Bull, Paul Stephen Corn, Grant Hokit, Bryce A. Maxell, James C. Munger, Aimee Wyrick Nov 2010

Non-Native Salmonids Affect Amphibian Occupancy At Multiple Spatial Scales, David S. Pilliod, Blake R. Hossack, Peter F. Bahls, Evelyn L. Bull, Paul Stephen Corn, Grant Hokit, Bryce A. Maxell, James C. Munger, Aimee Wyrick

Biology Faculty Publications and Presentations

Aim The introduction of non-native species into aquatic environments has been linked with local extinctions and altered distributions of native species. We investigated the effect of non-native salmonids on the occupancy of two native amphibians, the long-toed salamander (Ambystoma macrodactylum) and Columbia spotted frog (Rana luteiventris), across three spatial scales: water bodies, small catchments and large catchments.

Location Mountain lakes at ≥ 1500 m elevation were surveyed across the northern Rocky Mountains, USA.

Methods We surveyed 2267 water bodies for amphibian occupancy (based on evidence of reproduction) and fish presence between 1986 and 2002 and modelled …


GenHtr: A Tool For Comparative Assessment Of Genetic Heterogeneity In Microbial Genomes Generated By Massive Short-Read Sequencing, Gongxin Yu Oct 2010

GenHtr: A Tool For Comparative Assessment Of Genetic Heterogeneity In Microbial Genomes Generated By Massive Short-Read Sequencing, Gongxin Yu

Biology Faculty Publications and Presentations

Background: Microevolution is the study of short-term changes of alleles within a population and their effects on the phenotype of organisms. The result of the below-species-level evolution is heterogeneity, where populations consist of subpopulations with a large number of structural variations. Heterogeneity analysis is thus essential to our understanding of how selective and neutral forces shape bacterial populations over a short period of time. The Solexa Genome Analyzer, a next-generation sequencing platform, allows millions of short sequencing reads to be obtained with great accuracy, allowing for the ability to study the dynamics of the bacterial population at the whole genome …


Detection And Analysis Of The Bacterium, Xylella Fastidiosa, In Glassy-Winged Sharpshooter, Homalodisca Vitripennis, Populations In Texas, Daymon Hail, Forrest Mitchell, Isabelle Lauziere, Patrick Marshall, Jeff Brady, Blake Bextine Oct 2010

Detection And Analysis Of The Bacterium, Xylella Fastidiosa, In Glassy-Winged Sharpshooter, Homalodisca Vitripennis, Populations In Texas, Daymon Hail, Forrest Mitchell, Isabelle Lauziere, Patrick Marshall, Jeff Brady, Blake Bextine

Biology Faculty Publications and Presentations

The glassy-winged sharpshooter, Homalodisca vitripeninis Germar (Hemiptera: Cicadellidae), is a xylophagous insect that is an endemic pest of several economically important plants in Texas. H. vitripennis is the main vector of Xylella fastidiosa Wells (Xanthomonadales: Xanthomonadaceae), the bacterium that causes Pierce's disease of grapevine and can travel long distances putting much of Texas grape production at risk. Understanding the movement of H. vitripennis populations capable of transmitting X. fastidiosa into Pierce's-disease-free areas is critical for developing a management program for Pierce's disease. To that end, the USDA APHIS has developed a program to sample vineyards across Texas to monitor populations …


Foraging Strategies Are Related To Skull Morphology And Life History Traits Of Melanerpes Woodpeckers, David L. Leonard Jr., Julie A. Heath Oct 2010

Foraging Strategies Are Related To Skull Morphology And Life History Traits Of Melanerpes Woodpeckers, David L. Leonard Jr., Julie A. Heath

Biology Faculty Publications and Presentations

Links between morphology and foraging strategies have been well established for many vertebrate groups. Foraging strategies of Melanerpes woodpeckers are especially variable, with at least six species being proficient flycatchers; the remainder of the better known species do not flycatch. Our objective was to examine variation in foraging tactics as it relates to skull morphology and other life history traits among these species to better understand the biology of these diverse woodpeckers. We measured eight skull characters from 241 individuals representing 19 species, but focused on eight species for which we had the most data. We used the log-geometric mean …


Agolohymena Aspidocauda Nov. Gen., Nov. Spec., A Histophagous Freshwater Tetrahymenid Ciliate In The Family Deltopylidae (Ciliophora, Hymenostomatia), From Idaho (Northwest U.S.A.): Morphology, Ontogenesis And Molecular Phylogeny, William A. Bourland, Michaela C. Strüder-Kypke Aug 2010

Agolohymena Aspidocauda Nov. Gen., Nov. Spec., A Histophagous Freshwater Tetrahymenid Ciliate In The Family Deltopylidae (Ciliophora, Hymenostomatia), From Idaho (Northwest U.S.A.): Morphology, Ontogenesis And Molecular Phylogeny, William A. Bourland, Michaela C. Strüder-Kypke

Biology Faculty Publications and Presentations

Morphology, ontogeny and the molecular phylogeny of Agolohymena aspidocauda nov. gen., nov. spec., a new freshwater tetrahymenid ciliate from Idaho, U.S.A, are described. The ontogeny and histophagous mode of nutrition are similar to those of Deltopylum rhabdoides Fauré-Fremiet and Mugard, 1946. The new genus is placed with Deltopylum in the resurrected family Deltopylidae Song & Wilbert, 1989. We emend the diagnostic features of the family to include division by polytomy, right and left somatic kineties extending into the preoral suture, crook-shaped or sigmoid adoral membranelles 1 and 2, markedly reduced adoral membranelle 3 and a tetrahymenid silverline pattern. The main …


Pcif1 Modulates Pdx1 Protein Stability And Pancreatic Β Cell Function And Survival In Mice, Kathryn C. Claiborn, Mira M. Sachdeva, Corey E. Cannon, David N. Groff, Jeffrey D. Singer, Doris A. Stoffers Jul 2010

Pcif1 Modulates Pdx1 Protein Stability And Pancreatic Β Cell Function And Survival In Mice, Kathryn C. Claiborn, Mira M. Sachdeva, Corey E. Cannon, David N. Groff, Jeffrey D. Singer, Doris A. Stoffers

Biology Faculty Publications and Presentations

The homeodomain transcription factor pancreatic duodenal homeobox 1 (Pdx1) is a major mediator of insulin transcription and a key regulator of the β cell phenotype. Heterozygous mutations in PDX1 are associated with the development of diabetes in humans. Understanding how Pdx1 expression levels are controlled is therefore of intense interest in the study and treatment of diabetes. Pdx1 C terminus–interacting factor-1 (Pcif1, also known as SPOP) is a nuclear protein that inhibits Pdx1 transactivation. Here, we show that Pcif1 targets Pdx1 for ubiquitination and proteasomal degradation. Silencing of Pcif1 increased Pdx1 protein levels in cultured mouse β cells, and Pcif1 …


Present Effects Of Past Wildfires On Leaf Litter Breakdown In Stream Ecosystems, Peter Koetsier, Teresa R. B. Krause, Quenton M. Tuckett Jul 2010

Present Effects Of Past Wildfires On Leaf Litter Breakdown In Stream Ecosystems, Peter Koetsier, Teresa R. B. Krause, Quenton M. Tuckett

Biology Faculty Publications and Presentations

We investigated the present effects from a 10-year-old wildfire on leaf litter breakdown rates in 3 headwater streams in central Idaho. These systems experienced a massive debris flow one year after the fire. Based on soil instability and burn patterns, we identified 3 stream conditions: unburned, burned only, and burned/scoured. We placed leaf bags containing willow leaves (Salix sp.) in each stream type and removed bags at various time intervals until all bags were collected 100 days after their introduction. Leaf material was dried and weighed, and decay rate coefficients were calculated. Macroinvertebrates colonizing the bags were enumerated and identified, …


Caspase-Cleaved Tar Dna-Binding Protein-43 In Parkinson’S Disease And Dementia With Lewy Bodies, Polina Kokoulina, Troy T. Rohn Jun 2010

Caspase-Cleaved Tar Dna-Binding Protein-43 In Parkinson’S Disease And Dementia With Lewy Bodies, Polina Kokoulina, Troy T. Rohn

Biology Faculty Publications and Presentations

Background: TAR DNA-binding protein-43 (TDP-43) proteinopathies are classified based upon the extent of modified TDP-43 and include a growing number of neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration with ubiquitin immunoreactive, tau-negative inclusions (FTLD-U) and FTLD with motor neuron disease (FTLD-MND). Objective: The purpose of the study was to examine whether proteolytic modifications of TDP-43 are a relevant finding in Parkinson’s disease (PD) and dementia with Lewy Bodies (DLB). Methods: A novel site-directed caspase-cleavage antibody, termed TDP caspase-cleavage product antibody (TDPccp), was utilized based upon a known caspase-3 cleavage consensus site within TDP-43 at position 219. …


Selection Ratios On Community Aggregated Traits To Estimate Ecological Filters Imposed On Species By Sites, Nathanael I. Lichti, Michael T. Murphy Feb 2010

Selection Ratios On Community Aggregated Traits To Estimate Ecological Filters Imposed On Species By Sites, Nathanael I. Lichti, Michael T. Murphy

Biology Faculty Publications and Presentations

Variation in community structure is mediated by interactions between species traits and a site's environmental characteristics. Previously, data on community composition at sites has been employed to correlate trait and environmental variables (e.g., RLQ analysis) and to predict community-level expression of quantitative traits (i.e., community aggregated traits). Here, we demonstrate that the selection ratio, a method originating in animal resource selection studies, can estimate the ecological filters that site conditions impose on species traits by combining observed community aggregated traits with null models of species availability. This flexible, nonparametric approach expresses the filter at each site as a probability density …


Effects Of Small Increases In Corticosterone Levels On Morphology, Immune Function, And Feather Development, Michael W. Butler, Lynda L. Leppert, Alfred M. Dufty Jr. Jan 2010

Effects Of Small Increases In Corticosterone Levels On Morphology, Immune Function, And Feather Development, Michael W. Butler, Lynda L. Leppert, Alfred M. Dufty Jr.

Biology Faculty Publications and Presentations

Stressors encountered during avian development may affect an individual’s phenotype, including immunocompetence, growth, and feather quality. We examined effects of simulated chronic low-level stress on American kestrel (Falco sparverius) nestlings. Continuous release of corticosterone, a hormone involved in the stress response, can model chronic stress in birds. We implanted 13-d-old males with either corticosterone-filled implants or shams and measured their growth, immune function, and feather coloration.We found no significant differences between groups at the end of the weeklong exposure period in morphometrics (mass, tarsus, wing length, and asymmetry), immunocompetence (cutaneous immunity, heterophil/lymphocyte ratio, and humoral immunity), or feather …


Impacts Of An Orange Oil Solvent And Stickem On The Detection Of Xylella Fastidiosa Dna In Glassy-Winged Sharpshooters, Homalodisca Vitripennis (Hemiptera: Cicadellidae), Patrick Marshall, Daymon Hail, Forrest Mitchell, Blake Bextine Jan 2010

Impacts Of An Orange Oil Solvent And Stickem On The Detection Of Xylella Fastidiosa Dna In Glassy-Winged Sharpshooters, Homalodisca Vitripennis (Hemiptera: Cicadellidae), Patrick Marshall, Daymon Hail, Forrest Mitchell, Blake Bextine

Biology Faculty Publications and Presentations

Xylella fastidiosa is a plant pathogenic bacterium that causes many economically important agricultural diseases and is transmitted by the glassy-winged sharpshooter, Homalodisca vitripennis (Hemiptera: Cicadellidae). Efficient detection of X. fastidiosa in field collected H. vitripennis in an area-wide management program can contribute to risk assessment associated with insect presence in vineyards. Prior to conducting molecular assays for detection of X. fastidiosa in individual insects, H. vitripennis must be removed from yellow sticky traps with a solvent such as orange oil. In this study, we determined the effect of orange oil concentration on extraction of individual H. vitripennis following trap removal …


Phenotypic Divergence During The Invasion Of Phyla Canescens In Australia And France: Evidence For Selection-Driven Evolution, Cheng-Yuan Xu, Mic H. Julien, Mohammad Fatemi, Christophe Girod, Rieks D. Van Klinken, Caroline L. Gross, Stephen J. Novak Jan 2010

Phenotypic Divergence During The Invasion Of Phyla Canescens In Australia And France: Evidence For Selection-Driven Evolution, Cheng-Yuan Xu, Mic H. Julien, Mohammad Fatemi, Christophe Girod, Rieks D. Van Klinken, Caroline L. Gross, Stephen J. Novak

Biology Faculty Publications and Presentations

Rapid adaptive evolution has been advocated as a mechanism that promotes invasion. Demonstrating adaptive evolution in invasive species requires rigorous analysis of phenotypic shifts driven by selection. Here, we document selection-driven evolution of Phyla canescens, an Argentine weed, in two invaded regions (Australia and France). Invasive populations possessed similar or higher diversity than native populations, and displayed mixed lineages from different sources, suggesting that genetic bottlenecks in both countries might have been alleviated by multiple introductions. Compared to native populations, Australian populations displayed more investment in sexual reproduction, whereas French populations possessed enhanced vegetative reproduction and growth. We partitioned …


Mitochondrial Physiology Of Diapausing And Developing Embryos Of The Annual Killifish Austrofundulus Limnaeus: Implications For Extreme Anoxia Tolerance, Jeffrey M. Duerr, Jason E. Podrabsky Jan 2010

Mitochondrial Physiology Of Diapausing And Developing Embryos Of The Annual Killifish Austrofundulus Limnaeus: Implications For Extreme Anoxia Tolerance, Jeffrey M. Duerr, Jason E. Podrabsky

Biology Faculty Publications and Presentations

Diapausing embryos of the annual killifish Austrofundulus limnaeus have the highest reported anoxia tolerance of any vertebrate and previous studies indicate modified mitochondrial physiology likely supports anoxic metabolism. Functional mitochondria isolated from diapausing and developing embryos of the annual killifish exhibited VO2, respiratory control ratios (RCR), and P:O ratios consistent with those obtained from other ectothermic vertebrate species. Reduced oxygen consumption associated with dormancy in whole animal respiration rates are correlated with maximal respiration rates of mitochondria isolated from diapausing versus developing embryos. P:O ratios for developing embryos were similar to those obtained from adult liver, but were diminished in …


The Isolation Of Viruses Infecting Archaea, Kenneth M. Stedman, Kate Porter, Mike L. Dyall-Smith Jan 2010

The Isolation Of Viruses Infecting Archaea, Kenneth M. Stedman, Kate Porter, Mike L. Dyall-Smith

Biology Faculty Publications and Presentations

A mere 50 viruses of Archaea have been reported to date; these have been investigated mostly by adapting methods used to isolate bacteriophages to the unique growth conditions of their archaeal hosts. The most numerous are viruses of thermophilic Archaea. These viruses have been discovered by screening enrichment cultures and novel isolates from environmental samples for their ability to form halos of growth inhibition, or by using electron microscopy to screen enrichment cultures for virus-like particles. Direct isolation without enrichment has not yet been successful for viruses of extreme thermophiles. On the other hand, most viruses of extreme halophiles, the …


Fecal-Sac Ingestion By Spotted Towhees, Jenny E. Mckay, Michael T. Murphy, Sarah Bartos Smith, Jennifer K. Richardson Aug 2009

Fecal-Sac Ingestion By Spotted Towhees, Jenny E. Mckay, Michael T. Murphy, Sarah Bartos Smith, Jennifer K. Richardson

Biology Faculty Publications and Presentations

Altricial nestlings encase excrement in fecal sacs that parents remove by either ingesting them or transporting them away from the nest. Ingestion may allow energetically or nutritionally deprived parents to recapture energy or nutrients that might be lost because of nestlings' inefficient digestion (the "parental-nutrition hypothesis"), but ingestion may also permit parents to avoid flights from the nest that interfere with parental care (e.g., brooding young; the "economic-disposal hypothesis"). We used a hypothetico-deductive approach to test the two hypotheses' ability to account for fecal-sac ingestion by the Spotted Towhee (Pipilo maculatus). We confirmed the parental-nutrition hypothesis' predictions that …


American Kestrel Reproduction: Evidence For The Selection Hypothesis And The Role Of Dispersal, Karen Steenhof, Julie A. Heath Jul 2009

American Kestrel Reproduction: Evidence For The Selection Hypothesis And The Role Of Dispersal, Karen Steenhof, Julie A. Heath

Biology Faculty Publications and Presentations

Many hypotheses attempt to explain why younger, less experienced birds have relatively low reproductive output. We evaluated reproductive patterns of marked American Kestrels Falco sparverius nesting in boxes in southwestern Idaho from 1992 to 2006 to test predictions of these hypotheses. Results were consistent with the selection (differential mortality) hypothesis and did not support the constraint, restraint or recruitment hypotheses. Most known-age Kestrels nested in their first year of life, and there was no apparent short-term or long-term reproductive advantage to delayed breeding. The number of years that Kestrels nested in study area boxes ranged from 1 to 6 years, …


Activity And Interactions Of Liposomal Antibiotics In Presence Of Polyanions And Sputum Of Patients With Cystic Fibrosis, Misagh Alipour, Zacharias E. Suntres, Majed Halwani, Ali Azghani, Abdelwahab Omri May 2009

Activity And Interactions Of Liposomal Antibiotics In Presence Of Polyanions And Sputum Of Patients With Cystic Fibrosis, Misagh Alipour, Zacharias E. Suntres, Majed Halwani, Ali Azghani, Abdelwahab Omri

Biology Faculty Publications and Presentations

Background: To compare the effectiveness of liposomal tobramycin or polymyxin B against Pseudomonas aeruginosa in the Cystic Fibrosis (CF) sputum and its inhibition by common polyanionic components such as DNA, F-actin, lipopolysaccharides (LPS), and lipoteichoic acid (LTA). Methodology: Liposomal formulations were prepared from a mixture of 1,2-Dimyristoyl-sn-Glycero-3-Phosphocholine (DMPC) or 1,2-Dipalmitoyl-sn-Glycero-3-Phosphocholine (DPPC) and Cholesterol (Chol), respectively. Stability of the formulations in different biological milieus and antibacterial activities compared to conventional forms in the presence of the aforementioned inhibitory factors or CF sputum were evaluated. Results: The formulations were stable in all conditions tested with no significant differences compared to the controls. …


Environmental Regulation Of Dormancy Loss In Lomatium Dissectum (Apiaceae) Seeds, Melissa Scholten, Jacklyn Donahue, Nancy L. Shaw, Marcelo Serpe May 2009

Environmental Regulation Of Dormancy Loss In Lomatium Dissectum (Apiaceae) Seeds, Melissa Scholten, Jacklyn Donahue, Nancy L. Shaw, Marcelo Serpe

Biology Faculty Publications and Presentations

Background and aims Lomatium dissectum (Apiaceae) is a perennial, herbaceous plant of wide distribution in Western North America. At the time of dispersal, L. dissectum seeds are dormant and have underdeveloped embryos. The aims of this work were to determine the requirements for dormancy break and germination, to characterize the type of seed dormancy, and to determine the effect of dehydration after embryo growth on seed viability and secondary dormancy.

Methods The temperature requirements for embryo growth and germination were investigated under growth chamber and field conditions. The effect of GA3 on embryo growth was also analyzed to determine the …


Lead Bullet Fragments In Venison From Rifle-Killed Deer: Potential For Human Dietary Exposure, W. Grainger Hunt, Richard T. Watson, J. Lindsay Oaks, Chris N. Parish, Kurt K. Burnham, Russell L. Tucker, James R. Belthoff, Garret Hart Apr 2009

Lead Bullet Fragments In Venison From Rifle-Killed Deer: Potential For Human Dietary Exposure, W. Grainger Hunt, Richard T. Watson, J. Lindsay Oaks, Chris N. Parish, Kurt K. Burnham, Russell L. Tucker, James R. Belthoff, Garret Hart

Biology Faculty Publications and Presentations

Human consumers of wildlife killed with lead ammunition may be exposed to health risks associated with lead ingestion. This hypothesis is based on published studies showing elevated blood lead concentrations in subsistence hunter populations, retention of ammunition residues in the tissues of hunter-killed animals, and systemic, cognitive, and behavioral disorders associated with human lead body burdens once considered safe. Our objective was to determine the incidence and bioavailability of lead bullet fragments in hunter-killed venison, a widely-eaten food among hunters and their families. We radiographed 30 eviscerated carcasses of White-tailed Deer (Odocoileus virginianus) shot by hunters with standard …