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An Unusually Colored Red-Backed Salamander (Plethodon Cinerus) From Northern Virginia, Joseph C. Mitchell, Thomas K. Pauley, C. Todd Georgel

Virginia Journal of Science

We describe an orange-pink, patternless, translucent morph of the Red-backed Salamander (Plethodon cinereus) found in northern Virginia on 27 September 2001. This is the first description of this unusual phenotype in this terrestrial salamander.

Aintegumenta Utilizes A Mode Of Dna Recognition Distinct From That Used By Proteins Containing A Single Ap2 Domain, Beth A. Krizek

Faculty Publications

The Arabidopsis protein AINTEGUMENTA (ANT) is an important regulator of organ growth during flower development. ANT is a member of the AP2 subclass of the AP2/ERF family of plant-specific transcription factors. These proteins contain either one or two copies of a DNA-binding domain called the AP2 domain. Here, it is shown that ANT can act as a transcriptional activator in yeast through binding to a consensus ANT-binding site. This activity was used as the basis for a genetic screen to identify amino acids that are critical for the DNA binding ability of ANT. Mutants that showed reduced or no activation …

Lack Of Widespread Organochlorine Pesticide Contamination In South American Resident Passerines, Given Harper, A. Capparella, J. Klemens, J. Frick

Scholarship

Recent studies have documented the existence of organochlorine (OC) pesticides and metabolites— notably p,p'-DDE, dieldrin and heptachlor epoxide—in the nglg range in many species of Neotropical migrant passerines that breed in the Nearctic region and winter in the Neotropics (e.g., Kannan 1991; Harper et al. 1996; Klemens et al. 2000; Bartuszevige et al. 2002). This is despite the banning and/or restricted use of OC pesticides in the United States and Canada in the 1970s and the observed decline in DDT residues in migratory songbirds seen in the 1970s (Johnston 1974). Apparently, these relatively short-lived birds are still being exposed to …

Keys To The Mammals And Mammal Skulls Of The Northern Coastal Plain Of Virginia, John F. Pagels, A. Scott Bellows, Joseph C. Mitchell

Virginia Journal of Science

This publication is designed to function as a tool for the identification of mammal species that occur on the Coastal Plain of northern Virginia. We provide whole-body and skull keys to the 40 species that occur in this region. Baseline data for this work were collected during several studies conducted on Fort A.P. Hill, Caroline County. The intended audience includes interested naturalists, teachers, students, field biologists, and natural resource managers.

Effects Of Regular Exercise Training On Skeletal Muscle Contractile Function, Robert H. Fitts

Biological Sciences Faculty Research and Publications

Skeletal muscle function is critical to movement and one's ability to perform daily tasks, such as eating and walking. One objective of this article is to review the contractile properties of fast and slow skeletal muscle and single fibers, with particular emphasis on the cellular events that control or rate limit the important mechanical properties. Another important goal of this article is to present the current understanding of how the contractile properties of limb skeletal muscle adapt to programs of regular exercise.

Blackwell Publishing Ltd. Chondrocranial, Hyobranchial And Internal Oral Morphology In Larvae Of The Basal Bufonid Genus Melanophryniscus (Amphibia: Anura), Peter M. Larson, Rafael O. De Sá, Diego Arrieta

Biology Faculty Publications

Melanophryniscus is a genus of small toads inhabiting the southern portion of South America. This genus is considered basal within the family Bufonidae. Data on larval chondrocranial morphology do not exist for the genus and larval internal oral anatomy has only been described for a single species. Here, we describe chondrocranial and internal oral morphology in Melanophryniscus montevidensis, M. orejasmirandai and M. sanmartini. Chondrocranial morphology is similar among the species examined. Comparisons with other bufonids and with outgroup taxa suggest that the following chondrocranial characters may represent synapomorphies for the Bufonidae: free (or absent) ceratobranchial IV, a reduced …

Development Of A Maize Molecular Evolutionary Genomic Database, Chunguang Du, Edward Buckler, Spencer Muse

Department of Biology Faculty Scholarship and Creative Works

PANZEA is the first public database for studying maize genomic diversity. It was initiated as a repository of genomic diversity for an NSF Plant Genome project on 'Maize Evolutionary Genomics'. PANZEA is hosted at the Bioinformatics Research Center, North Carolina State University, and is open to the public (http://statgen.ncsu.edu/panzea). PANZEA is designed to capture the interrelationships between germplasm, molecular diversity, phenotypic diversity and genome structure. It has the ability to store, integrate and visualize DNA sequence, enzymatic, SSR (simple sequence repeat) marker, germplasm and phenotypic data. The relational data model is selected and implemented in Oracle. An automated DNA sequence …

Two Arabidopsis Circadian Oscillators Can Be Distinguished By Differential Temperature Sensitivity, Todd P. Michael, Patrice A. Salome, C. Robertson Mcclung

Dartmouth Scholarship

Circadian rhythms are widespread in nature and reflect the activity of an endogenous biological clock. In metazoans, the circadian system includes a central circadian clock in the brain as well as distinct clocks in peripheral tissues such as the retina or liver. Similarly, plants have distinct clocks in different cell layers and tissues. Here, we show that two different circadian clocks, distinguishable by their sensitivity to environmental temperature signals, regulate the transcription of genes that are expressed in the Arabidopsis thaliana cotyledon. One oscillator, which regulates CAB2 expression, responds preferentially to light–dark versus temperature cycles and fails to respond to …

Fc177, A Minor Dec-1 Proprotein, Is Necessary To Prevent Ectopic Aggregation Of The Endochorion During Eggshell Assembly In Drosophila, Debra Kay Mauzy-Melitz, Gail L. Waring

Biological Sciences Faculty Research and Publications

The Drosophila eggshell is a highly specialized extracellular matrix that forms between the oocyte and the surrounding epithelial follicle cells during late oogenesis. The dec-1 gene, which is required for proper eggshell assembly, produces three proproteins that are cleaved within the vitelline membrane layer to multiple derivatives. The different spatial distributions of the cleaved derivatives suggest that they play distinct roles in eggshell assembly. Using extant dec-1 mutations in conjunction with genetically engineered dec-1 transgenes, we show that, although all three dec-1 proproteins, fc106, fc125, and fc177, are required for female fertility, gross morphological abnormalities in the eggshell are observed …

Mapping The Galpha13 Binding Interface Of The Rgrgs Domain Of P115rhogef, Zhe Chen, William D. Singer, Clark D. Wells, Stephen R. Sprang, Paul C. Sternweis

Biological Sciences Faculty Publications

Structural requirements for function of the Rho GEF (guanine nucleotide exchange factor) regulator of G protein signaling (rgRGS) domains of p115RhoGEF and homologous exchange factors differ from those of the classical RGS domains. An extensive mutagenesis analysis of the p115RhoGEF rgRGS domain was undertaken to determine its functional interface with the Galpha(13) subunit. Results indicate that there is global resemblance between the interaction surface of the rgRGS domain with Galpha(13) and the interactions of RGS4 and RGS9 with their Galpha substrates. However, there are distinct differences in the distribution of functionally critical residues between these structurally similar surfaces and an …

Removal Of Pcr Inhibitors From Soil Dna By Chemical Flocculation, Michael D. Braid, Laura M. Daniels, Christopher L. Kitts

Biological Sciences

Extracting high-purity DNA directly from soil has become essential for the study of microorganisms in environmental samples. However, many soils contain compounds that inhibit enzymes involved in manipulating DNA. In this study, chemical flocculation using multivalent cations was investigated as a potential method for eliminating soil-based inhibitors during the extraction process. The addition of AlNH4(SO4)2 during extraction significantly reduced the co-purification of PCR inhibitors with minimal loss of DNA yield.

Survey Of Whole Air Data From The Second Airborne Biomass Burning And Lightning Experiment Using Principal Component Analysis, Felisa A. Smith, Yunsoo Choi, Scott Elliott, Isobel J. Simpson, Donald R. Blake, Jonah J. Colman, Manvendra K. Dubey, Simone Meinardi, F. Sherwood Rowland, Tomoko Shirai

Biology Faculty & Staff Publications

Hydrocarbon and halocarbon measurements collected during the second airborne Biomass Burning and Lightning Experiment (BIBLE-B) were subjected to a principal component analysis (PCA), to test the capability for identifying intercorrelated compounds within a large whole air data set. The BIBLE expeditions have sought to quantify and understand the products of burning, electrical discharge, and general atmospheric chemical processes during flights arrayed along the western edge of the Pacific. Principal component analysis was found to offer a compact method for identifying the major modes of composition encountered in the regional whole air data set. Transecting the continental monsoon, urban and industrial …

Religious Naturalism And Naturalizing Morality, Ursula Goodenough

Biology Faculty Research

I first offer some reflections on the term religious naturalism. I then outline how moral thought might be configured in the context of religious naturalism. It is proposed that the goal of morality is to generate a flourishing community and that humans negotiate their social interactions using moral capacities that are cultivated in the context of culture. Six such capacities are considered: strategic reciprocity, humaneness, fair–mindedness, courage, reverence, and mindfulness. Moral capacities are contrasted with moral susceptibilities, fueled by self–interest, and brought to the fore in times of stress and humiliation. The essay is in two parts. I first respond …

Vocal Development In American Kestrel (Falco Sparverius) Nestlings, John A. Smallwood, Valerie Dudajek, Sivajini Gilchrist, Mary Anne Smallwood

Department of Biology Faculty Scholarship and Creative Works

We studied the acoustical characteristics of calls made by nestling American Kestrels (Falco sparverius). A total of 563 vocal samples was obtained from 88 chicks (49 males and 39 females) from 20 broods. Thirteen frequency, three numerical, and two temporal characteristics were measured using audio spectrography. Discriminant function analysis failed to distinguish the calls of male and female chicks, but univariate and principal component analyses suggest that vocal ontogeny proceeds more rapidly in males than in females. The acoustical characteristics of call notes changed in a consistent manner as nestlings matured, and by day 16 chicks produced calls similar to …

Biochemical Composition Of Embryonic Blue Crabs Callinectes Sapidus Rathbun 1896 (Crustacea : Decapoda) From The Gulf Of Mexico, Janet R. Jacobs, Patricia M. Biesiot, Harriet M. Perry, Christine Trigg

Faculty Publications

Blue crab Callinectes sapidus embryos from the Mississippi Sound were sampled in spring and in late summer to determine patterns of biochemical composition and of yolk utilization during embryogenesis and to ascertain potential seasonal differences in biochemical composition. The diameter of spring embryos was similar to 6% greater than summer embryos but this significant size difference was due to increased water content, not to increased organic content. The general trend in initial biochemical composition was similar in both seasons; protein was the primary component at similar to 50% of initial dry weight followed by lipid (similar to 30%), ash (similar …

Regulation Of Chloride Permeability By Endogenously Produced Tyramine In The Drosophila Malpighian Tubule, Edward M. Blumenthal

Biological Sciences Faculty Research and Publications

The Malpighian (renal) tubule of Drosophila melanogaster is a useful model for studying epithelial transport. The purpose of this study was to identify factors responsible for modulating transepithelial chloride conductance in isolated tubules. I have found that tyrosine and several of its metabolites cause an increase in chloride conductance. The most potent of these agonists is tyramine, which is active at low nanomolar concentrations; the pharmacology of this response matches that of the previously published cloned insect tyramine receptor. In addition, the tubule appears capable of synthesizing tyramine from applied tyrosine, as shown by direct measurement of tyrosine decarboxylase activity. …

Activated Epha4 Receptor In Xenopus Laevis Acts Rhrough Src- Like Tyrosine Kinase P59fyn To Inhibit Rhoa Gtpase, Svetlana Grabauskiene

Master's Theses and Doctoral Dissertations

Eph receptors and their ligands, ephrins, have been implicated in many important developmental processes and in tumorigenesis. The activation of EphA4 receptors in the frog, Xenopus laevis, causes loss of cell adhesion, tight junctions, and stress fibers. Previous studies revealed that these receptors achieve their cellular effects at least in part by inhibiting RhoA GTPase. However, what links these GTPases with the EphA4 receptor remained unknown.

In an attempt to investigate involvement of the Src-like tyrosine kinase p59fyn in EphA4 signaling, a series of experiments was planned using the chimeric receptor EPP. The findings presented in this thesis indicate …

Microalgal-Meiofaunal Trophic Relationships In Muddy Intertidal Estuarine Sediments, James L. Pinckney, Kevin R. Carman, S. Elizabeth Lumsden, Sabrina N. Hymel

Faculty Publications

The determination of the primary factors controlling carbon (C) transfer rates in situ are a basic requirement for developing a mechanistic view of the processes that regulate benthic microbial community structure and function. In many estuarine ecosystems, the base of the food web is dominated by microalgal production; however, information on the quantitative relationships and process rates of meiofaunal grazers and benthic microalgal (BMA) producers is limited to a few habitats and short temporal scales. The primary objective of this study was to examine the trophic interactions between meiofaunal grazers and BMA producers to determine if grazing is a primary …

Temperature Regulation And The Constraints Of Climate In The Eared Grebe, Hugh I. Ellis, Joseph R. Jehl Jr

Biology: Faculty Scholarship

Eared Grebes (Podiceps nigricollis) encounter a variety of climatic regimes in their annual cycle. The most dramatic occur while on staging areas in autumn. We investigated the thermoregulatory abilities of the Eared Grebe to determine how they coped with these climate changes during staging. The basal metabolic rate (BMR) was higher than predicted. Mass-specific BMR was 1.212 mL O2/g·h for birds averaging 317 g. The thermoneutral zone is wide and extended from 15°C to 38°C. Minimal thermal conductance and average body temperature were not unusual. We conclude that Eared Grebes live most of the year under thermoneutral conditions and that …

Energetic Adaptations Along A Broad Latitudinal Gradient: Implications For Widely Distributed Assemblages, Jeffrey Gibson Miner, James E. Garvey, Dennis R. Devries, Russell A. Wright

Biological Sciences Faculty Publications

Most community-based models in ecology assume that all individuals within a species respond similarly to environmental conditions and thereby exert identical effects as consumers or prey. Rather, individuals differ among systems, with important implications for population demographics and community interactions. For widely distributed assemblages made up of poikilotherms with high first-year mortality, species-specific differences in growth reaction norms as affected by both temperature and genotype will influence biotic interactions. For a broadly distributed fish assemblage, first-year growth does not vary with latitude for a planktivorous prey species, but declines with increasing latitude for a terminal piscivore. Size-based competitive interactions between …

Five-Member Gene Family Of Bartonella Quintana, Michael F. Minnick, Kate N. Sappington, Laura S. Smitherman, Siv G. E. Andersson, Olof Karlberg, James A. Carroll

Biological Sciences Faculty Publications

Bartonella quintana, the agent of trench fever and an etiologic agent of bacillary angiomatosis, has an extraordinarily high hemin requirement for growth compared to other bacterial pathogens. We previously identified the major hemin receptor of the pathogen as a 30-kDa surface protein, termed HbpA. This report describes four additional homologues that share approximately 48% amino acid sequence identity with hbpA. Three of the genes form a paralagous cluster, termed hbpCAB, whereas the other members, hbpD and hbpE, are unlinked. Secondary structure predictions and other evidence suggest that Hbp family members are beta-barrels located in the outer membrane and contain eight …

The B-Subunit Of The Arabidopsis G Protein Negatively Regulates Auxin-Induced Cell Division And Affects Multiple Developmental Processes, Hemayet Ullah

Department of Biology Faculty Publications

Plant cells respond to low concentrations of auxin by cell expansion, and at a slightly higher concentration, these cells divide. Previous work revealed that null mutants of the alpha-subunit of a putative heterotrimeric G protein (GPA1) have reduced cell division. Here, we show that this prototypical G protein complex acts mechanistically by controlling auxin sensitivity toward cell division. Loss-of-function G protein mutants have altered auxin-mediated cell division throughout development, especially during the auxin-induced formation of lateral and adventitious root primordia. Ectopic expression of the wild-type Galpha-subunit phenocopies the Gbeta mutants (auxin hypersensitivity), probably by sequestering the Gbetagamma-subunits, whereas overexpression of …

Multiple Roles For Hedgehog Signaling In Zebrafish Pituitary Development, Jennifer L. Sbrogna, Michael J.F. Barresi, Rolf O. Karlstrom

Biological Sciences: Faculty Publications

The endocrine-secreting lobe of the pituitary gland, or adenohypophysis, forms from cells at the anterior margin of the neural plate through inductive interactions involving secreted morphogens of the Hedgehog (Hh), fibroblast growth factor (FGF), and bone morphogenetic protein (BMP) families. To better understand when and where Hh signaling influences pituitary development, we have analyzed the effects of blocking Hh signaling both pharmacologically (cyclopamine treatments) and genetically (zebrafish Hh pathway mutants). While current models state that Shh signaling from the oral ectoderm patterns the pituitary after placode induction, our data suggest that Shh plays a direct early role in both pituitary …

Bible A Whole-Air Sampling As A Window On Asian Biogeochemistry, Felisa A. Smith, Scott Elliott, Donald R. Blake, Nikola J. Blake, Manvendra D. Dubey, F. Sherwood Rowland, Barkley C. Sive

Biology Faculty & Staff Publications

Asian trace gas and aerosol emissions into carbon, nitrogen, and other elemental cycles will figure prominently in near term Earth system evolution. Atmospheric hydrocarbon measurements resolve numerous chemical species and can be used to investigate sourcing for key geocarriers. A recent aircraft study of biomass burning and lightning (BIBLE A) explored the East Asian atmosphere and was unique in centering on the Indonesian archipelago. Samples of volatile organics taken over/between the islands of Japan, Saipan, Java, and Borneo are here examined as a guide to whole-air-based studies of future Asian biogeochemistry. The midlatitude onshore/offshore pulse and tropical convection strongly influence …

Meiotic And Mitotic Phenotypes Conferred By The Blm1-1 Mutation In Saccharomyces Cerevisiae And Msh4 Suppression Of The Bleomycin Hypersusceptibility, Georgia Anyatonwu, Ediberto Garcia, Ajay Pramanik, Marie Powell, Carol Wood Moore

Publications and Research

Oxidative damage can lead to a number of diseases, and can be fatal. The blm1-1 mutation of Saccharomyces cerevisiae confers hypersusceptibility to lethal effects of the oxidative, anticancer and antifungal agent, bleomycin. For the current report, additional defects conferred by the mutation in meiosis and mitosis were investigated. The viability of spores produced during meiosis by homozygous normal BLM1/BLM1, heterozygous BLM1/blm1-1, and homozygous mutant blm1-1/blm1-1 diploid strains was studied and compared. Approximately 88% of the tetrads derived from homozygous blm1-1/blm1-1 mutant diploid cells only produced one or two viable spores. In contrast, just one tetrad among all BLM1/BLM1 and BLM1/blm1-1 …

The Vascular Flora Of The Tablelands: A Natural Region In The Northeastern Section Of The Knobs Of Kentucky, Kim L. Feeman

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Kim L. Feeman on January 22, 2003.

Wing-Assisted Incline Running And The Evolution Of Flight, Kenneth P. Dial

Biological Sciences Faculty Publications

Flapping wings of galliform birds are routinely used to produce aerodynamic forces oriented toward the substrate to enhance hindlimb traction. Here, I document this behavior in natural and laboratory settings. Adult birds fully capable of aerial flight preferentially employ wing-assisted incline running (WAIR), rather than flying, to reach elevated refuges (such as cliffs, trees, and boulders). From the day of hatching and before attaining sustained aerial flight, developing ground birds use WAIR to enhance their locomotor performance through improved foot traction, ultimately permitting vertical running. WAIR provides insight from behaviors observable in living birds into the possible role of incipient …

Up-Regulation Of Neuronal Calcium Sensor-1 (Ncs-1) In The Prefrontal Cortex Of Schizophrenic And Bipolar Patients, Phil Ok Koh, Ashiwel S. Undieh, Robert Levenson, Patricia S. Goldman-Rakic, Michael S. Lidow

Publications and Research

The delineation of dopamine dysfunction in the mentally ill has been a long-standing quest of biological psychiatry. The present study focuses on a recently recognized group of dopamine receptor- interacting proteins as possible novel sites of dysfunction in schizophrenic and bipolar patients. We demonstrate that the dorsolateral prefrontal cortex in schizophrenia and bipolar cases from the Stanley Foundation Neuropathology Consortium display significantly elevated levels of the D2 dopamine receptor desensitization regulatory protein, neuronal calcium sensor-1. These levels of neuronal calcium sensor-1 were not influenced by age, gender, hemisphere, cause of death, postmortem period, alcohol consumption, or antipsychotic and mood stabilizing …

Asymmetry Of The Central Apparatus Defines The Location Of Active Microtubule Sliding In Chlamydomonas Flagella, Matthew J. Wargo, Elizabeth F. Smith

Dartmouth Scholarship

Regulation of ciliary and flagellar motility requires spatial control of dynein-driven microtubule sliding. However, the mechanism for regulating the location and symmetry of dynein activity is not understood. One hypothesis is that the asymmetrically organized central apparatus, through interactions with the radial spokes, transmits a signal to regulate dynein-driven microtubule sliding between subsets of doublet microtubules. Based on this model, we hypothesized that the orientation of the central apparatus defines positions of active microtubule sliding required to control bending in the axoneme. To test this, we induced microtubule sliding in axonemes isolated from wild-type and mutant Chlamydomonas cells, and then …

Richard Goldschmidt: Hopeful Monsters And Other 'Heresies', Michael Dietrich

Dartmouth Scholarship

Richard Goldschmidt is remembered today as one of the most controversial biologists of the twentieth century. Although his work on sex determination and physiological genetics earned him accolades from his peers, his rejection of the classical gene and his unpopular theories about evolution significantly damaged his scientific reputation. This article reviews Goldschmidt's life and work, with an emphasis on his controversial views.