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Horizontal Transfer Of A Nitrate Assimilation Gene Cluster And Ecological Transitions In Fungi: A Phylogenetic Study, Jason C. Slot, David S. Hibbett Oct 2007

Horizontal Transfer Of A Nitrate Assimilation Gene Cluster And Ecological Transitions In Fungi: A Phylogenetic Study, Jason C. Slot, David S. Hibbett

Biology

High affinity nitrate assimilation genes in fungi occur in a cluster (fHANT-AC) that can be coordinately regulated. The clustered genes include nrt2, which codes for a high affinity nitrate transporter; euknr, which codes for nitrate reductase; and NAD(P)H-nir, which codes for nitrite reductase. Homologs of genes in the fHANT-AC occur in other eukaryotes and prokaryotes, but they have only been found clustered in the oomycete Phytophthora (heterokonts). We performed independent and concatenated phylogenetic analyses of homologs of all three genes in the fHANT-AC. Phylogenetic analyses limited to fungal sequences suggest that the fHANT-AC has been transferred horizontally from a basidiomycete …


Contrasting Infection Strategies In Generalist And Specialist Wasp Parasitoids Of Drosophila Melanogaster, Todd A. Schlenke, Jorge Morales, Shubha Govind, Andrew G. Clark Oct 2007

Contrasting Infection Strategies In Generalist And Specialist Wasp Parasitoids Of Drosophila Melanogaster, Todd A. Schlenke, Jorge Morales, Shubha Govind, Andrew G. Clark

Publications and Research

Although host–parasitoid interactions are becoming well characterized at the organismal and cellular levels, much remains to be understood of the molecular bases for the host immune response and the parasitoids’ ability to defeat this immune response. Leptopilina boulardi and L. heterotoma, two closely related, highly infectious natural parasitoids of Drosophila melanogaster, appear to use very different infection strategies at the cellular level. Here, we further characterize cellular level differences in the infection characteristics of these two wasp species using newly derived, virulent inbred strains, and then use whole genome microarrays to compare the transcriptional response of Drosophila to each. While …


The Potential Role Of Probiotics In Reducing Poverty-Associated Infections In Developing Countries, Kingsley Anukam Oct 2007

The Potential Role Of Probiotics In Reducing Poverty-Associated Infections In Developing Countries, Kingsley Anukam

Data and Test Instruments

Probiotics are defined by the Food and Agricultural Organization/ World Health Organization as “live microorganisms which when administered in adequate amounts confer a health benefit on the host” [1]. The potential benefits of their use have not been adequately investigated, especially in the developing world. Japan introduced Yakult, a probiotic fermented food drink in 1935, and in the Northern hemisphere, research and use of probiotics has gained an unprecedented momentum in the last decade [2]. Use of probiotics is not uncommon in Europe [3], but in many developing countries use of probiotics in its present definition is a foreign concept. …


A Non-Circadian Role For Clock-Genes In Sleep Homeostasis: A Strain Comparison, Paul Franken, Ryan Thomason, H. Craig Heller, Bruce F. O'Hara Oct 2007

A Non-Circadian Role For Clock-Genes In Sleep Homeostasis: A Strain Comparison, Paul Franken, Ryan Thomason, H. Craig Heller, Bruce F. O'Hara

Biology Faculty Publications

BACKGROUND: We have previously reported that the expression of circadian clock-genes increases in the cerebral cortex after sleep deprivation (SD) and that the sleep rebound following SD is attenuated in mice deficient for one or more clock-genes. We hypothesized that besides generating circadian rhythms, clock-genes also play a role in the homeostatic regulation of sleep. Here we follow the time course of the forebrain changes in the expression of the clock-genes period (per)-1, per2, and of the clock-controlled gene albumin D-binding protein (dbp) during a 6 h SD and subsequent recovery sleep in three inbred strains of mice for which …


Evaluating Forensic Dna Evidence - A Day-Long Workshop, Dan E. Krane, William C. Thompson Oct 2007

Evaluating Forensic Dna Evidence - A Day-Long Workshop, Dan E. Krane, William C. Thompson

Biological Sciences Faculty Publications

No abstract provided.


Fuzzy Data Sets, William D. Stansfield Oct 2007

Fuzzy Data Sets, William D. Stansfield

Biological Sciences

No abstract provided.


Documenting Lineages From My ‘Littlest Ancestor’ To My Deep Ancestral Roots, Emily F. Schmitt Lavin Oct 2007

Documenting Lineages From My ‘Littlest Ancestor’ To My Deep Ancestral Roots, Emily F. Schmitt Lavin

Biology Faculty Proceedings, Presentations, Speeches, Lectures

No abstract provided.


Biophysical Study Of The Sh2 Domain Of Human Tensin, Yogesh Mohan Kulkarni Oct 2007

Biophysical Study Of The Sh2 Domain Of Human Tensin, Yogesh Mohan Kulkarni

Doctoral Dissertations

Cell migration is a key characteristic of embryogenesis, inflammation, wound healing, tumor cell metastasis and a broad range of other normal and pathological processes. Accumulating evidence suggests that the protein tensin provides a physical link between transmembrane receptors, proteins commonly associated with signal transduction, and the actin cytoskeleton. Adhesion involves three broad classes of macromolecules: ExtraCellular Matrix (ECM) molecules, transmembrane adhesion receptors, and intracellular adhesion plaque proteins. Tensin is particularly enriched in Fibrillar Adhesions (FA's), though it is also present to a modest extent in Focal Contacts (FC's). Src Homology 2 (SH2) domains function in the transmission of molecular signals …


The Effectiveness Of Prophylactic Eye Drops On The Reversal Of Uv-Light Induced Cataracts, Contessa Bly Bowman Oct 2007

The Effectiveness Of Prophylactic Eye Drops On The Reversal Of Uv-Light Induced Cataracts, Contessa Bly Bowman

Theses and Dissertations

Cataracts are a cloudiness of the lens within the eye which obstructs vision. They are found in many species including rats, dogs, and humans. Vision is hindered where this "cloudiness", made of water build up and broken crystalline, proteins take form. Oculvet is an eye medication, used by veterinarians, containing carnosine as its active ingredient. Topical application of carnosine is reported to be an effective treatment for the prevention and removal of pre-existing cataracts. For this experiment, Sprague- Dawley rats were anesthetized and exposed to ultraviolet radiation, UVB and UVC. They were divided into four groups (n = 32), three …


Correlation Of Eastern Wild Turkey Poult:Hen Ratios With Population Indices To Detect Reproductive Density Dependence, Jay D. Mcghee, Jim Berkson Oct 2007

Correlation Of Eastern Wild Turkey Poult:Hen Ratios With Population Indices To Detect Reproductive Density Dependence, Jay D. Mcghee, Jim Berkson

Virginia Journal of Science

Knowledge of how density affects population growth is important for the harvest management of wild turkey. Unfortunately, available time-series are often too short for statistical detection of density dependence. The correlation between wild turkey recruitment and population size was assessed using data from 7 state wildlife agencies, circumventing the problem of short time-series by using multiple datasets. Correlation coefficients were calculated between surveyed poult:hen ratios and harvest-based population indices for 31 geographic or harvest management regions. Estimated correlation coefficients were tested for homogeneity to determine if an average correlation could be calculated. Correlation coefficients for the 29 regions ranged from …


Native Plant Diversity Resists Invasion At Both Low And High Resource Levels, John L. Maron, Marilyn Marler Oct 2007

Native Plant Diversity Resists Invasion At Both Low And High Resource Levels, John L. Maron, Marilyn Marler

Biological Sciences Faculty Publications

Human modification of the environment is causing both loss of species and changes in resource availability. While studies have examined how species loss at the local level can influence invasion resistance, interactions between species loss and other components of environmental change remain poorly studied. In particular, the manner in which native diversity interacts with resource availability to influence invasion resistance is not well understood. We created experimental plant assemblages that varied in native species (1–16 species) and/or functional richness (defined by rooting morphology and phenology; one to five functional groups). We crossed these diversity treatments with resource (water) addition to …


Depauperate Small Mammal Communities In Managed Pine Plantations In Eastern Virginia, James D. Dolan, Robert K. Rose Oct 2007

Depauperate Small Mammal Communities In Managed Pine Plantations In Eastern Virginia, James D. Dolan, Robert K. Rose

Virginia Journal of Science

Loblolly pine (Pinus taeda L.) plantations of four different ages were examined to identify changes in the small mammal community in relation to changes in the vegetational community. Small mammals were evaluated during five seasons using two methods of trapping. Live traps accounted for 65% of captures and seven of nine species, whereas pitfall traps yielded eight species, of which two were not taken with live traps. For both trap types, catch rates averaged less than two per 100 trap-nights, very low even for pine forests. Both abundance and biomass of small mammals declined with increasing stand age, whereas species …


The Chlamydomonas Genome Reveals The Evolution Of Key Animal And Plant Functions, Sabeeha S. Merchant, Simon E. Prochnik, Olivier Vallon, Elizabeth H. Harris, Steven J. Karpowicz, George B. Witman, Astrid Terry, Asaf Salamov, Lillian K. Fritz-Laylin, Laurence Maréchal-Drouard, Wallace F. Marshall, Liang-Hu Qu, David R. Nelson, Anton A. Sanderfoot, Martin H. Spalding, Vladimir V. Kapitonov, Qinghu Ren, Patrick Ferris, Erika Lindquist, Harris Shapiro, Susan M. Lucas, Jane Grimwood, Jeremy Schmutz, Pierre Cardol, Heriberto Cerutti, Guillaume Chanfreau, Chun-Long Chen, Valerie Cognat, Martin T. Croft, Rachel Dent, Susan Dutcher, Emilio Fernández, Hideya Fukuzawa, David González-Ballester, Diego González-Halphen, Armin Hallmann, Marc Hanikenne, Michael Hippler, William Inwood, Kamel Jabbari, Ming Kalanon, Richard Kuras, Paul A. Lefebvre, Stéphane D. Lemaire, Alexey V. Lobanov, Martin Lohr, Andrea Manuell, Iris Meier, Laurens Mets, Maria Mittag, Telsa Mittelmeier, James V. Moroney, Jeffrey Moseley, Carolyn Napoli, Aurora M. Nedelcu, Krishna Niyogi, Sergey V. Novoselov, Ian T. Paulsen, Greg Pazour, Saul Purton, Jean-Philippe Ral, Diego Mauricio Riaño-Pachón, Wayne Riekhof, Linda Rymarquis, Michael Schroda, David Stern, James Umen, Robert Willows, Nedra Wilson, Sara Lana Zimmer, Jens Allmer, Janneke Balk, Katerina Bisova, Chong-Jian Chen, Mark Elias, Karla Gendler, Charles Hauser, Mary Rose Lamb, Heidi Ledford, Joanne C. Long, Jun Minagawa, M. Dudley Page, Junmin Pan, Wirulda Pootakham, Sanja Roje, Annkatrin Rose, Eric Stahlberg, Aimee M. Terauchi, Pinfen Yang, Steven Ball, Chris Bowler, Carol L. Dieckmann, Vadim N. Gladyshev, Pamela Green, Richard Jorgensen, Stephen Mayfield, Bernd Mueller-Roeber, Sathish Rajamani, Richard T. Sayre, Peter Brokstein, Inna Dubchak, David Goodstein, Leila Hornick, Y. Wayne Huang, Jinal Jhaveri, Yigong Luo, Diego Martinez, Wing Chi Abby Ngau, Bobby Otillar, Alexander Poliakov, Aaron Porter, Lukasz Szajkowski, Gregory Werner, Kemin Zhou, Igor V. Grigoriev, Daniel S. Rokhsar, Arthur R. Grossman Oct 2007

The Chlamydomonas Genome Reveals The Evolution Of Key Animal And Plant Functions, Sabeeha S. Merchant, Simon E. Prochnik, Olivier Vallon, Elizabeth H. Harris, Steven J. Karpowicz, George B. Witman, Astrid Terry, Asaf Salamov, Lillian K. Fritz-Laylin, Laurence Maréchal-Drouard, Wallace F. Marshall, Liang-Hu Qu, David R. Nelson, Anton A. Sanderfoot, Martin H. Spalding, Vladimir V. Kapitonov, Qinghu Ren, Patrick Ferris, Erika Lindquist, Harris Shapiro, Susan M. Lucas, Jane Grimwood, Jeremy Schmutz, Pierre Cardol, Heriberto Cerutti, Guillaume Chanfreau, Chun-Long Chen, Valerie Cognat, Martin T. Croft, Rachel Dent, Susan Dutcher, Emilio Fernández, Hideya Fukuzawa, David González-Ballester, Diego González-Halphen, Armin Hallmann, Marc Hanikenne, Michael Hippler, William Inwood, Kamel Jabbari, Ming Kalanon, Richard Kuras, Paul A. Lefebvre, Stéphane D. Lemaire, Alexey V. Lobanov, Martin Lohr, Andrea Manuell, Iris Meier, Laurens Mets, Maria Mittag, Telsa Mittelmeier, James V. Moroney, Jeffrey Moseley, Carolyn Napoli, Aurora M. Nedelcu, Krishna Niyogi, Sergey V. Novoselov, Ian T. Paulsen, Greg Pazour, Saul Purton, Jean-Philippe Ral, Diego Mauricio Riaño-Pachón, Wayne Riekhof, Linda Rymarquis, Michael Schroda, David Stern, James Umen, Robert Willows, Nedra Wilson, Sara Lana Zimmer, Jens Allmer, Janneke Balk, Katerina Bisova, Chong-Jian Chen, Mark Elias, Karla Gendler, Charles Hauser, Mary Rose Lamb, Heidi Ledford, Joanne C. Long, Jun Minagawa, M. Dudley Page, Junmin Pan, Wirulda Pootakham, Sanja Roje, Annkatrin Rose, Eric Stahlberg, Aimee M. Terauchi, Pinfen Yang, Steven Ball, Chris Bowler, Carol L. Dieckmann, Vadim N. Gladyshev, Pamela Green, Richard Jorgensen, Stephen Mayfield, Bernd Mueller-Roeber, Sathish Rajamani, Richard T. Sayre, Peter Brokstein, Inna Dubchak, David Goodstein, Leila Hornick, Y. Wayne Huang, Jinal Jhaveri, Yigong Luo, Diego Martinez, Wing Chi Abby Ngau, Bobby Otillar, Alexander Poliakov, Aaron Porter, Lukasz Szajkowski, Gregory Werner, Kemin Zhou, Igor V. Grigoriev, Daniel S. Rokhsar, Arthur R. Grossman

Biological Sciences Faculty Research and Publications

Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It is a model system for studying chloroplast-based photosynthesis, as well as the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited from the common ancestor of plants and animals, but lost in land plants. We sequenced the ∼120-megabase nuclear genome of Chlamydomonas and performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated with the function and biogenesis of chloroplasts or eukaryotic flagella. Analyses of the Chlamydomonas genome advance our understanding of the ancestral eukaryotic cell, …


Arbuscular Mycorrhizal Fungal Root Colonization And Inoculum Propagules In Deciduos Floodplain Forests Of Southwestern Michigan, Usa, Peter G. Avis, Sara D. Foster, Paul D. Olexia Oct 2007

Arbuscular Mycorrhizal Fungal Root Colonization And Inoculum Propagules In Deciduos Floodplain Forests Of Southwestern Michigan, Usa, Peter G. Avis, Sara D. Foster, Paul D. Olexia

Faculty and Professional Research

We examined the arbuscular mycorrhizal (AM) fungi of temperate deciduous floodplain forests in southwest Michigan, USA, and the relationship between soil moisture and AM fungal root colonization and inoculum. In four floodplain forests, AM root colonization was measured for roots collected from soil samples taken along soil moisture, micro-topography and vegetation gradients. An AM fungal inoculum bioassay was also conducted using these samples to measure the amount of infective propagules found across these gradients. Although soil moisture had no significant effect on either AM parameter measured, the effect of forest site was significant in most instances. We also found a …


Determining Domain Similarity And Domain-Protein Similarity Using Functional Similarity Measurements Of Gene Ontology Terms, Lisa Michelle Guntly, Jennifer Leopold, Anne M. Maglia Oct 2007

Determining Domain Similarity And Domain-Protein Similarity Using Functional Similarity Measurements Of Gene Ontology Terms, Lisa Michelle Guntly, Jennifer Leopold, Anne M. Maglia

Computer Science Faculty Research & Creative Works

Protein domains typically correspond to major functional sites of a protein. Therefore, determining similarity between domains can aid in the comparison of protein functions, and can provide a basis for grouping domains based on function. One strategy for comparing domain similarity and domain-protein similarity is to use similarity measurements of annotation terms from the Gene Ontology (GO). In this paper five methods are analyzed in terms of their usefulness for comparing domains, and comparing domains to proteins based on GO terms.


Inference Of Genetic Regulatory Networks With Recurrent Neural Network Models Using Particle Swarm Optimization, Rui Xu, Donald C. Wunsch, Ronald L. Frank Oct 2007

Inference Of Genetic Regulatory Networks With Recurrent Neural Network Models Using Particle Swarm Optimization, Rui Xu, Donald C. Wunsch, Ronald L. Frank

Electrical and Computer Engineering Faculty Research & Creative Works

Genetic regulatory network inference is critically important for revealing fundamental cellular processes, investigating gene functions, and understanding their relations. The availability of time series gene expression data makes it possible to investigate the gene activities of whole genomes, rather than those of only a pair of genes or among several genes. However, current computational methods do not sufficiently consider the temporal behavior of this type of data and lack the capability to capture the complex nonlinear system dynamics. We propose a recurrent neural network (RNN) and particle swarm optimization (PSO) approach to infer genetic regulatory networks from time series gene …


Phylogeny And Trichome Evolution In The Plant Family Brassicaceae, Mark Alan Beilstein Sep 2007

Phylogeny And Trichome Evolution In The Plant Family Brassicaceae, Mark Alan Beilstein

Dissertations

The plant family Brassicaceae is economically important and contains the model genetic system Arabidopsis thaliana. Previous phylogenetic studies indicated that the historic classification system of the family was highly artificial, with several tribes likely to be para- or polyphyletic. However, these studies sampled fewer than 30 of the 338 genera of the family. We expanded the sampling of genera by four-fold and inferred phylogeny from both the chloroplast gene ndhF and the nuclear gene phytochrome A (PHYA) to determine which of the previously delimited 19 tribes of the family were monophyletic. Results from both ndhF and PHYA …


Draft Genome Of The Filarial Nematode Parasite Brugia Malayi, Elodie Ghedin, Shiliang Wang, David Spiro, Elisabet Caler, Qi Zhao, Jonathan Crabtree, Jonathan E. Allen, Arthur L. Delcher, David B. Guiliano, Diego Miranda-Saavedra, Samuel V. Angiuoli, Todd Creasy, Paolo Amedeo, Brian Haas, Najib M. El-Sayed, Jennifer R. Wortman, Tamara Feldblyum, Luke Tallon, Michael Schatz, Martin Shumway, Hean Koo, Steven L. Salzberg, Seth Schobel, Mihaela Pertea, Mihai Pop, Owen White, Geoffrey J. Barton, Clotilde K.S. Carlow, Michael J. Crawford, Jennifer Daub, Et Al, Steven A. Williams Sep 2007

Draft Genome Of The Filarial Nematode Parasite Brugia Malayi, Elodie Ghedin, Shiliang Wang, David Spiro, Elisabet Caler, Qi Zhao, Jonathan Crabtree, Jonathan E. Allen, Arthur L. Delcher, David B. Guiliano, Diego Miranda-Saavedra, Samuel V. Angiuoli, Todd Creasy, Paolo Amedeo, Brian Haas, Najib M. El-Sayed, Jennifer R. Wortman, Tamara Feldblyum, Luke Tallon, Michael Schatz, Martin Shumway, Hean Koo, Steven L. Salzberg, Seth Schobel, Mihaela Pertea, Mihai Pop, Owen White, Geoffrey J. Barton, Clotilde K.S. Carlow, Michael J. Crawford, Jennifer Daub, Et Al, Steven A. Williams

Biological Sciences: Faculty Publications

Parasitic nematodes that cause elephantiasis and river blindness threaten hundreds of millions of people in the developing world. We have sequenced the ∼90 megabase (Mb) genome of the human filarial parasite Brugia malayi and predict ∼11,500 protein coding genes in 71 Mb of robustly assembled sequence. Comparative analysis with the free-living, model nematode Caenorhabditis elegans revealed that, despite these genes having maintained little conservation of local synteny during ∼350 million years of evolution, they largely remain in linkage on chromosomal units. More than 100 conserved operons were identified. Analysis of the predicted proteome provides evidence for adaptations of B. malayi …


Thalamic Gating Of Auditory Responses In Telencephalic Song Control Nuclei, Melissa J. Coleman, Arani Roy, J. Martin Wild, Richard Mooney Sep 2007

Thalamic Gating Of Auditory Responses In Telencephalic Song Control Nuclei, Melissa J. Coleman, Arani Roy, J. Martin Wild, Richard Mooney

WM Keck Science Faculty Papers

In songbirds, nucleus Uvaeformis (Uva) is the sole thalamic input to the telencephalic nucleus HVC (used as a proper name), a sensorimotor structure essential to learned song production that also exhibits state dependent responses to auditory presentation of the bird’s own song (BOS). The role of Uva in influencing HVC auditory activity is unknown. Using in vivo extracellular and intracellular recordings in urethane-anesthetized zebra finches, we characterized the auditory properties of Uva and examined its influence on auditory activity in HVC and in the telencephalic nucleus interface (NIf), the main auditory afferent of HVC and a corecipient of Uva input. …


Supplementary Figure 1, Melissa J. Coleman, Arani Roy, J. Martin Wild, Richard Mooney Sep 2007

Supplementary Figure 1, Melissa J. Coleman, Arani Roy, J. Martin Wild, Richard Mooney

WM Keck Science Faculty Papers

Supplemental data for "Thalamic Gating of Auditory Responses in Telencephalic Song Control Nuclei."


The Organizational Effects Of Oxytocin On The Central Expression Of Estrogen Receptor Alpha And Oxytocin In Adulthood, Kristin M. Kramer, Shigeto Yoshida, Eros Papademetriou, Bruce S. Cushing Sep 2007

The Organizational Effects Of Oxytocin On The Central Expression Of Estrogen Receptor Alpha And Oxytocin In Adulthood, Kristin M. Kramer, Shigeto Yoshida, Eros Papademetriou, Bruce S. Cushing

Biology Faculty Research

Background: Previous studies have demonstrated that neonatal manipulation of oxytocin (OT) has effects on the expression of estrogen receptor alpha (ER alpha) and the central production of oxytocin observed in juveniles ( at weaning, 21 days of age). The goal of this study was to determine whether the effects of neonatal manipulation of OT last into adulthood, and if the effects differ from those observed during the early postnatal period. On the first day of life, prairie voles ( Microtus ochrogaster) received one of three doses of OT (High, 3 mu g; Med, 0.3 mu g; Low, 0.03 mu g), …


Extracellular Stimuli Specifically Regulate Localized Levels Of Individual Neuronal Mrnas, Dianna E. Willis, Erna A. Van Niekerk, Yukio Sasaki, Mariano Mesngon, Tanuja T. Merianda, Gervan G. Williams, Marvin Kendall, Deanna S. Smith, Gary J. Bassell, Jeffery L. Twiss Sep 2007

Extracellular Stimuli Specifically Regulate Localized Levels Of Individual Neuronal Mrnas, Dianna E. Willis, Erna A. Van Niekerk, Yukio Sasaki, Mariano Mesngon, Tanuja T. Merianda, Gervan G. Williams, Marvin Kendall, Deanna S. Smith, Gary J. Bassell, Jeffery L. Twiss

Faculty Publications

Subcellular regulation of protein synthesis requires the correct localization of messenger RNAs (mRNAs) within the cell. In this study, we investigate whether the axonal localization of neuronal mRNAs is regulated by extracellular stimuli. By profiling axonal levels of 50 mRNAs detected in regenerating adult sensory axons, we show that neurotrophins can increase and decrease levels of axonal mRNAs. Neurotrophins (nerve growth factor, brainderived neurotrophic factor, and neurotrophin-3) regulate axonal mRNA levels and use distinct downstream signals to localize individual mRNAs. However, myelin-associated glycoprotein and semaphorin 3A regulate axonal levels of different mRNAs and elicit the opposite effect on axonal mRNA …


A Study Of The Mussels (Mollusca: Bivalvia: Unionidae) Of Symmes Creek And Tributaries In Jackson, Gallia And Lawrence Counties, Ohio, Michael A. Hoggarth, David A. Kimberly, Benjamin G. Van Allen Sep 2007

A Study Of The Mussels (Mollusca: Bivalvia: Unionidae) Of Symmes Creek And Tributaries In Jackson, Gallia And Lawrence Counties, Ohio, Michael A. Hoggarth, David A. Kimberly, Benjamin G. Van Allen

Biology and Earth Science Faculty Scholarship

Freshwater mussels (family Unionidae) are among the most threatened of Ohio's aquatic fauna. Interest in their biogeography has increased as their distribution and abundance has declined. This study was performed to assess the status of the mussels of Symmes Creek and it major tributaries in southern Ohio. Of the 24 species of mussels known to have inhabited this watershed, 16 were found alive in the system in 2004 and 2005 and two others were found as freshly dead shells. These species are thought to represent the extant mussel fauna in the system today. Of the remaining six species collected prior …


Dessication Stress, Steven C. Hand, Michael A. Menze Sep 2007

Dessication Stress, Steven C. Hand, Michael A. Menze

Faculty Research & Creative Activity

The threat of desiccation for organisms inhabiting the intertidal zone occurs during emersion at low tides or when organisms are positioned in the high intertidal zone, where wetting occurs primarily by spring tides, storm waves, and spray. Drying due to evaporative water loss is the most common mechanism for dehydration, although during winter in northern temperate regions freezing can also occur, which reduces the liquid water in extracellular fluids and can lead to intracellular dehydration in multicellular organisms. Freezing tolerance has been reported and characterized for a number of intertidal invertebrates, including gastropods such as an air-breathing snail and a …


Floral Biology Of Physaria Ludoviciana (Brassicaceae), A Plant Rare To The Midwest, Ann E. Claerbout, Janice M. Coons, Henry R. Owen, Kenneth R. Robertson Sep 2007

Floral Biology Of Physaria Ludoviciana (Brassicaceae), A Plant Rare To The Midwest, Ann E. Claerbout, Janice M. Coons, Henry R. Owen, Kenneth R. Robertson

Faculty Research & Creative Activity

Physaria ludoviciana (Brassicaceae) is rare in Illinois, Minnesota, and Wisconsin. Environmental effects on floral development are unclear. Both self-compatibility and self-incompatibility occur within Physaria species. Objectives were to describe flowers, to determine how photoperiod affects flower development, and to predict whether flowers are self-compatible or self-incompatible. For photoperiods, greenhouse-grown plants were placed in either 16 or 8 hr photoperiods. Inflorescences and open flowers were counted weekly. For pollination, flowers were self-pollinated or cross-pollinated. Plants developed inflorescences after 20 and 28 d in long and short days, respectively. Inflorescences/plant increased for both photoperiods throughout the study. In short days, plants produced …


Genetic Evidence For The Persistence Of The Critically Endangered Sierra Nevada Red Fox In California, John D. Perrine, John P. Pollinger, Benjamin N. Sacks, Reginald H. Barrett, Robert K. Wayne Sep 2007

Genetic Evidence For The Persistence Of The Critically Endangered Sierra Nevada Red Fox In California, John D. Perrine, John P. Pollinger, Benjamin N. Sacks, Reginald H. Barrett, Robert K. Wayne

Biological Sciences

California is home to both the native state-threatened Sierra Nevada red fox (Vulpes vulpes necator), which historically inhabited high elevations of the Sierra Nevada and Cascade mountains, and to multiple low-elevation red fox populations thought to be of exotic origin. During the past few decades the lowland populations have dramatically expanded their distribution, and possibly moved into the historic range of the native high-elevation fox. To determine whether the native red fox persists in its historic range in California, we compared mitochondrial cytochrome-b haplotypes of the only currently-known high-elevation population (n = 9 individuals) to samples …


The Unusual 23s Rrna Gene Of Coxiella Burnetii: Two Self-Splicing Group I Introns Flank A 34-Base-Pair Exon, And One Element Lacks The Canonical Omega G, Rahul Raghavan, Scott R. Miller, Linda D. Hicks, Michael F. Minnick Sep 2007

The Unusual 23s Rrna Gene Of Coxiella Burnetii: Two Self-Splicing Group I Introns Flank A 34-Base-Pair Exon, And One Element Lacks The Canonical Omega G, Rahul Raghavan, Scott R. Miller, Linda D. Hicks, Michael F. Minnick

Biological Sciences Faculty Publications

We describe the presence and characteristics of two self-splicing group I introns in the sole 23S rRNA gene of Coxiella burnetii. The two group I introns, Cbu.L1917 and Cbu.L1951, are inserted at sites 1917 and 1951 (Escherichia coli numbering), respectively, in the 23S rRNA gene of C. bumetii. Both introns were found to be self-splicing in vivo and in vitro even though the terminal nucleotide of Cbu.L1917 is adenine and not the canonical conserved guanine, termed Omega G, found in Cbu.L1951 and all other group I introns described to date. Predicted secondary structures for both introns were constructed and revealed …


Transcriptional Regulation Of The Heme Binding Protein Gene Family Of Bartonella Quintana Is Accomplished By A Novel Promoter Element And Iron Response Regulator, James M. Battisti, Laura S. Smitherman, Kate N. Sappington, Nermi L. Parrow, Rahul Raghavan, Michael F. Minnick Sep 2007

Transcriptional Regulation Of The Heme Binding Protein Gene Family Of Bartonella Quintana Is Accomplished By A Novel Promoter Element And Iron Response Regulator, James M. Battisti, Laura S. Smitherman, Kate N. Sappington, Nermi L. Parrow, Rahul Raghavan, Michael F. Minnick

Biological Sciences Faculty Publications

We previously identified a five-member family of hemin-binding proteins (Hbp's) of Bartonella quintana that bind hemin on the outer surface but share no homology with known bacterial heme receptors. Subsequently, we demonstrated that expression of the hbp family is significantly influenced by oxygen, heme, and temperature conditions encountered by the pathogen in the human host and the body louse vector; e.g., we observed a dramatic (>100-fold) increase in hbpC transcript levels in response to the "louse-like" temperature of 30 degrees C. The goal of the present study was to identify a transcription factor(s) involved in the coordinated and differential …


Algal Regulation Of Extracellular Enzyme Activity In Stream Microbial Communities Associated With Inert Substrata And Detritus, Steven T. Rier, Kevin A. Kuehn, Steven N. Francoeur Sep 2007

Algal Regulation Of Extracellular Enzyme Activity In Stream Microbial Communities Associated With Inert Substrata And Detritus, Steven T. Rier, Kevin A. Kuehn, Steven N. Francoeur

Faculty Publications

We tested the hypothesis that algae influence the activities of extracellular enzymes involved in mineralization processes within microbial assemblages in streams. We tested the prediction that the factors that influence algal biomass and photosynthesis (i.e., diel fluctuations in photosynthetically active radiation [PAR], long-term variations in light regime, and community development stage) would have a corresponding effect on extracellular enzyme activities. We also tested the prediction that algae would influence enzyme activities on inorganic substrata and in detrital communities where they ultimately would influence plant litter decomposition rates. We allowed microbial communities to develop on inert substrata (glass-fiber filters) or on …


Land Cover Types Of The Las Vegas Wash, Nevada, Seth A. Shanahan, Dave Silverman, Art Ehrenberg Sep 2007

Land Cover Types Of The Las Vegas Wash, Nevada, Seth A. Shanahan, Dave Silverman, Art Ehrenberg

Publications (WR)

Vegetation type, extent, continuity, and structure are some of the most important factors that determine wildlife diversity and distribution. Other contributing factors that shape wildlife communities include disturbance, competition, climate, and water availability. Because vegetation communities in the southwestern U.S. gradate sharply along zones of soil moisture, wildlife are often restricted to specific vegetation types. Along the Las Vegas Wash (Wash), Nevada, more than 250 wildlife species have been documented to occur in distinct wetland, riparian, and upland vegetation types. Recent studies have investigated the diversity and distribution of amphibians, birds, fishes, mammals, and reptiles (Shanahan 2005, 2005a, Van Dooremolen …