Life Sciences Commons^™

Single-Locus Versus Multilocus Patterns Of Local Adaptation To Climate In Eastern White Pine (Pinus Strobus, Pinaceae), Om P. Rajora, Andrew J. Eckert, John W. R. Zinck

Biology Publications

Natural plant populations are often adapted to their local climate and environmental conditions, and populations of forest trees offer some of the best examples of this pattern. However, little empirical work has focused on the relative contribution of single-locus versus multilocus effects to the genetic architecture of local adaptation in plants/forest trees. Here, we employ eastern white pine (Pinus strobus) to test the hypothesis that it is the inter-genic effects that primarily drive climate-induced local adaptation. The genetic structure of 29 range-wide natural populations of eastern white pine was determined in relation to local climatic factors using both …

Planar Cell Polarity Genes Frizzled3a, Vangl2, And Scribble Are Required For Spinal Commissural Axon Guidance, Simon D. Sun, Ashley M. Purdy, Gregory S. Walsh

Biology Publications

Background

A fundamental feature of early nervous system development is the guidance of axonal projections to their targets in order to assemble neural circuits that control behavior. Spinal commissural neurons are an attractive model to investigate the multiple guidance cues that control growth cone navigation both pre- and post-midline crossing, as well as along both the dorsal–ventral (D–V) and anterior–posterior (A–P) axes. Accumulating evidence suggests that guidance of spinal commissural axons along the A–P axis is dependent on components of the planar cell polarity (PCP) signaling pathway. In the zebrafish, the earliest born spinal commissural neuron to navigate the midline …

Cadherin-2 Is Required Cell Autonomously For Collective Migration Of Facial Branchiomotor Neurons, Jane K. Rebman, Kathryn E. Kirchoff, Gregory S. Walsh

Biology Publications

Collective migration depends on cell-cell interactions between neighbors that contribute to their overall directionality, yet the mechanisms that control the coordinated migration of neurons remains to be elucidated. During hindbrain development, facial branchiomotor neurons (FBMNs) undergo a stereotypic tangential caudal migration from their place of birth in rhombomere (r)4 to their final location in r6/7. FBMNs engage in collective cell migration that depends on neuron-to-neuron interactions to facilitate caudal directionality. Here, we demonstrate that Cadherin-2-mediated neuron-to-neuron adhesion is necessary for directional and collective migration of FBMNs. We generated stable transgenic zebrafish expressing dominant-negative Cadherin-2 (Cdh2ΔEC) driven by the islet1 promoter. …

In Silico Identification Of Essential Proteins In Corynebacterium Pseudotuberculosis Based On Protein-Protein Interaction Networks, Edson Luiz Folador, Paulo Vinícius Sanches Daltro De Carvalho, Wanderson Marques Silva, Rafaela Salgado Ferreira, Artur Silva, Michael Gromiha, Preetam Ghosh, Debmalya Barh, Vasco Azevedo, Richard Röttger

Biology Publications

Background

Corynebacterium pseudotuberculosis (Cp) is a gram-positive bacterium that is classified into equi and ovis serovars. The serovar ovis is the etiological agent of caseous lymphadenitis, a chronic infection affecting sheep and goats, causing economic losses due to carcass condemnation and decreased production of meat, wool, and milk. Current diagnosis or treatment protocols are not fully effective and, thus, require further research of Cp pathogenesis.

Results

Here, we mapped known protein-protein interactions (PPI) from various species to nine Cp strains to reconstruct parts of the potential Cp interactome and to identify potentially essential proteins serving as putative drug …

Prothonotary Warbler Nestling Growth And Condition Inresponse To Variation In Aquatic And Terrestrial Preyavailability, Jenna C. Dodson, Nicholas J. Moy, Lesley P. Bulluck

Biology Publications

Aquatic prey subsidies entering terrestrial habitats are well documented, but little is known about the degree to which these resources provide fitness benefits to riparian consumers. Riparian species take advantage of seasonal pulses of both terrestrial and aquatic prey, although aquatic resources are often over-looked in studies of how diet influences the reproductive ecology of these organisms. Ideally, the timing of resource pulses should occur at the time of highest reproductive demand. This study investigates the availability of aquatic(mayfly) and terrestrial (caterpillar) prey resources as well as the nestling diet of the prothonotary warbler (Protonotaria citrea) at two sites along …

Simba: A Web Tool For Managing Bacterial Genome Assembly Generated By Ion Pgm Sequencing Technology, Diego C. B. Mariano, Felipe L. Pereira, Edgar L. Aguiar, Letícia C. Oliveira, Leandro Benevides, Luís C. Guimarães, Edson L. Folador, Thiago J. Sousa, Preetam Ghosh, Debmalya Barh, Henrique C. P. Figueiredo, Artur Silva, Rommel T. J. Ramos, Vasco A. C. Azevedo

Biology Publications

Background

The evolution of Next-Generation Sequencing (NGS) has considerably reduced the cost per sequenced-base, allowing a significant rise of sequencing projects, mainly in prokaryotes. However, the range of available NGS platforms requires different strategies and software to correctly assemble genomes. Different strategies are necessary to properly complete an assembly project, in addition to the installation or modification of various software. This requires users to have significant expertise in these software and command line scripting experience on Unix platforms, besides possessing the basic expertise on methodologies and techniques for genome assembly. These difficulties often delay the complete genome assembly projects.

Results …

Homo Heidelbergensis: The Tool To Our Success, Alexander Burkard

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Homo heidelbergensis, a physiological variant of the species Homo sapien, is an extinct species that existed in both Europe and parts of Asia from 700,000 years ago to roughly 300,000 years ago (carbon dating). This “subspecies” of Homo sapiens, as it is formally classified, is a direct ancestor of anatomically modern humans, and is understood to have many of the same physiological characteristics as those of anatomically modern humans while still expressing many of the same physiological attributes of Homo erectus, an earlier human ancestor. Since Homo heidelbergensis represents attributes of both species, it has therefore earned the classification as …

Grunt Variation In The Oyster Toadfish Opsanus Tau: Effect Of Size And Sex, Michael L. Fine, Tyler D. Waybright

Biology Publications

As in insects, frogs and birds, vocal activity in fishes tends to be more developed in males than in females, and sonic swimbladder muscles may be sexually dimorphic, i.e., either larger in males or present only in males. Male oyster toadfish Opsanus tau L produce a long duration, tonal boatwhistle advertisement call, and both sexes grunt, a short duration more pulsatile agonistic call. Sonic muscles are present in both sexes but larger in males. We tested the hypothesis that males would call more than females by inducing grunts in toadfish of various sizes held in a net and determined incidence …

Does Upper Extremity Training Influence Body Composition After Spinal Cord Injury?, Justin A. Fisher, Meredith A. Mcnelis, Ashraf S. Gorgey, David S. Dolbow, Lance L. Goetz

Biology Publications

Spinal cord injury (SCI) leads to serious body composition adaptations characterized by increasing whole body fat mass and decreased soft tissue lean mass (LM). These adaptations in body composition may lead to several cardio-metabolic disorders that reduce the quality of life, increase patients’ and caregivers’ burden and eventually leads to mortality. Exercise, an appropriate dietary regimen, and an active lifestyle may alleviate several of the negative effects on body composition after a SCI. Today however, there is no established consensus on the recommended dose, frequency or type of exercise to ameliorate several of the body composition sequelae after an acute …

Metagenomic Analysis Of Planktonic Microbial Consortia From A Non-Tidal Urban-Impacted Segment Of James River, Bonnie L. Brown, Rebecca V. Leprell, Rima B. Franklin, Maria C. Rivera, Francine M. Cabral, Hugh L. Eaves, Vicki Gardiakos, Kevin P. Keegan, Timothy L. King

Biology Publications

Knowledge of the diversity and ecological function of the microbial consortia of James River in Virginia, USA, is essential to developing a more complete understanding of the ecology of this model river system. Metagenomic analysis of James River's planktonic microbial community was performed for the first time using an unamplified genomic library and a 16S rDNA amplicon library prepared and sequenced by Ion PGM and MiSeq, respectively. From the 0.46-Gb WGS library (GenBank:SRR1146621; MG-RAST:4532156.3), 4 × 10 ⁶ reads revealed >3 × 10 ⁶ genes, 240 families of prokaryotes, and 155 families of eukaryotes. From the 0.68-Gb 16S library (GenBank:SRR2124995; …

Consequences Of Life History Switch Point Plasticity For Juvenile Morphology And Locomotion In The Túngara Frog, Julie Charbonnier, James R. Vonesh

Biology Publications

Many animals with complex life cycles can cope with environmental uncertainty by altering the timing of life history switch points through plasticity. Pond hydroperiod has important consequences for the fitness of aquatic organisms and many taxa alter the timing of life history switch points in response to habitat desiccation. For example, larval amphibians can metamorphose early to escape drying ponds. Such plasticity may induce variation in size and morphology of juveniles which can result in carry-over effects on jumping performance. To investigate the carry-over effects of metamorphic plasticity to pond drying, we studied the Túngara frog, Physalaemus pustulosus, a …

Evolutionary History Influences The Salinity Preference Of Bacterial Taxa In Wetland Soils, Ember M. Morrisey, Rima B. Franklin

Biology Publications

Salinity is a major driver of bacterial community composition across the globe. Despite growing recognition that different bacterial species are present or active at different salinities, the mechanisms by which salinity structures community composition remain unclear. We tested the hypothesis that these patterns reflect ecological coherence in the salinity preferences of phylogenetic groups using a reciprocal transplant experiment of fresh- and saltwater wetland soils. The salinity of both the origin and host environments affected community composition (16S rRNA gene sequences) and activity (CO2 and CH4 production, and extracellular enzyme activity). These changes in community composition and activity rates were …

Identification Of Eastern United States Reticulitermes Termite Species Via Pcr-Rflp, Assessed Using Training And Test Data, Ryan C. Garrick, Benjamin D. Collins, Rachel N. Yi, Rodney J. Dyer, Chaz Hyseni

Biology Publications

Reticulitermes termites play key roles in dead wood decomposition and nutrient cycling in forests. They also damage man-made structures, resulting in considerable economic loss. In the eastern United States, five species (R. flavipes, R. virginicus, R. nelsonae, R. hageni and R. malletei) have overlapping ranges and are difficult to distinguish morphologically. Here we present a molecular tool for species identification. It is based on polymerase chain reaction (PCR) amplification of a section of the mitochondrial cytochrome oxidase subunit II gene, followed by a three-enzyme restriction fragment length polymorphism (RFLP) assay, with banding patterns resolved via agarose gel electrophoresis. The assay …

Metagenomic Analysis Of Planktonic Microbial Consortia From A Non-Tidal Urban-Impacted Segment Of James River, Bonnie L. Brown, Rebecca V. Leprell, Rima B. Franklin, Maria C. Rivera, Francine M. Cabral, Hugh L. Eaves, Vicki Gardiakos, Kevin P. Keegan, Timothy L. King

Biology Publications

Knowledge of the diversity and ecological function of the microbial consortia of James River in Virginia, USA, is essential to developing a more complete understanding of the ecology of this model river system. Metagenomic analysis of James River's planktonic microbial community was performed for the first time using an unamplified genomic library and a 16S rDNA amplicon library prepared and sequenced by Ion PGM and MiSeq, respectively. From the 0.46-Gb WGS library (GenBank:SRR1146621; MG-RAST:4532156.3), 4 × 106 reads revealed >3 × 106 genes, 240 families of prokaryotes, and 155 families of eukaryotes. From the 0.68-Gb 16S library (GenBank:SRR2124995; MG-RAST:4631271.3; EMB:2184), …

Risk Assessment Based On Indirect Predation Cues: Revisiting Fine-Grained Variation, Michael W. Mccoy, Stefan K. Wheat, Karen M. Warkentin, James R. Vonesh

Biology Publications

To adaptively express inducible defenses, prey must gauge risk based on indirect cues of predation. However, the information contained in indirect cues that enable prey to fine-tune their phenotypes to variation in risk is still unclear. In aquatic systems, research has focused on cue concentration as the key variable driving threat-sensitive responses to risk. However, while risk is measured as individuals killed per time, cue concentration may vary with either the number or biomass killed. Alternatively, fine-grained variation in cue, that is, frequency of cue pulses irrespective of concentration, may provide a more reliable signal of risk. Here, we present …

Pectoral Sound Generation In The Blue Catfish Ictalurus Furcatus, Yasha Mohajer, Zachary Ghahramani, Michael L. Fine

Forensic Science Publications

Catfishes produce pectoral stridulatory sounds by “jerk” movements that rub ridges on the dorsal process against the cleithrum. We recorded sound synchronized with high-speed video to investigate the hypothesis that blue catfish Ictalurus furcatus produce sounds by a slip–stick mechanism, previously described only in invertebrates. Blue catfish produce a variably paced series of sound pulses during abduction sweeps (pulsers) although some individuals (sliders) form longer duration sound units (slides) interspersed with pulses. Typical pulser sounds are evoked by short 1–2 ms movements with a rotation of 2°–3°. Jerks excite sounds that increase in amplitude after motion stops, suggesting constructive interference, …

Understanding Host-Switching By Ecological Fitting, Sabrina B. L. Araujo, Mariana Pires Braga, Daniel R. Brooks, Salvatore J. Agosta, Eric P. Hoberg, Francisco W. Von Hartenthal, Walter A. Boeger

Biology Publications

Despite the fact that parasites are highly specialized with respect to their hosts, empirical evidence demonstrates that host switching rather than co-speciation is the dominant factor influencing the diversification of host-parasite associations. Ecological fitting in sloppy fitness space has been proposed as a mechanism allowing ecological specialists to host-switch readily. That proposal is tested herein using an individual-based model of host switching. The model considers a parasite species exposed to multiple host resources. Through time host range expansion can occur readily without the prior evolution of novel genetic capacities. It also produces non-linear variation in the size of the fitness …

Consequences Of Life History Switch Point Plasticity For Juvenile Morphology And Locomotion In The Túngara Frog, Julie Charbonnier, James R. Vonesh

Biology Publications

Many animals with complex life cycles can cope with environmental uncertainty by altering the timing of life history switch points through plasticity. Pond hydroperiod has important consequences for the fitness of aquatic organisms and many taxa alter the timing of life history switch points in response to habitat desiccation. For example, larval amphibians can metamorphose early to escape drying ponds. Such plasticity may induce variation in size and morphology of juveniles which can result in carry-over effects on jumping performance. To investigate the carry-over effects of metamorphic plasticity to pond drying, we studied the Túngara frog,Physalaemus pustulosus, a …

Evolutionary History Influences The Salinity Preference Of Bacterial Taxa In Wetland Soils, Ember Morrissey, Rima B. Franklin

Biology Publications

Salinity is a major driver of bacterial community composition across the globe. Despite growing recognition that different bacterial species are present or active at different salinities, the mechanisms by which salinity structures community composition remain unclear. We tested the hypothesis that these patterns reflect ecological coherence in the salinity preferences of phylogenetic groups using a reciprocal transplant experiment of fresh- and saltwater wetland soils. The salinity of both the origin and host environments affected community composition (16S rRNA gene sequences) and activity (CO2 and CH4 production, and extracellular enzyme activity). These changes in community composition and activity rates were …

Hannah Huddle: Visually Comparing Art And Science, Mark Hardison

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Hannah Huddle, a junior at VCU majoring in communications arts with a concentration in scientific illustration, has been working on a research project with VCU biology professor Dr. Lesley Bulluck, and a group of six students, researching the Prothonotary Warbler. Unlike most researchers, Huddle is both studying the biology of the bird and making illustrations of the bird and the research involving the Warbler.

A Nuclear Dna Perspective On Delineating Evolutionarily Significant Lineages In Polyploids: The Case Of The Endangered Shortnose Sturgeon (Acipenser Brevirostrum), Tim L. King, Anne P. Henderson, Boyd E. Kynard, Micah C. Kieffer, Douglas L. Peterson, Aaron W. Aunins, Bonnie L. Brown

Biology Publications

The shortnose sturgeon, Acipenser brevirostrum, oft considered a phylogenetic relic, is listed as an “endangered species threatened with extinction” in the US and “Vulnerable” on the IUCN Red List. Effective conservation of A. brevirostrum depends on understanding its diversity and evolutionary processes, yet challenges associated with the polyploid nature of its nuclear genome have heretofore limited population genetic analysis to maternally inherited haploid characters. We developed a suite of polysomic microsatellite DNA markers and characterized a sample of 561 shortnose sturgeon collected from major extant populations along the North American Atlantic coast. The 181 alleles observed at 11 loci …

Barrier Island Morphology And Sediment Characteristics Affect The Recovery Of Dune Building Grasses Following Storm-Induced Overwash, Steven T. Brantley, Spencer Bissett, Donald R. Young, Catherine W. V. Wolner, Laura J. Moore

Biology Publications

Barrier islands are complex and dynamic systems that provide critical ecosystem services to coastal populations. Stability of these systems is threatened by rising sea level and the potential for coastal storms to increase in frequency and intensity. Recovery of dune-building grasses following storms is an important process that promotes topographic heterogeneity and long-term stability of barrier islands, yet factors that drive dune recovery are poorly understood. We examined vegetation recovery in overwash zones on two geomorphically distinct (undisturbed vs. frequently overwashed) barrier islands on the Virginia coast, USA. We hypothesized that vegetation recovery in overwash zones would be driven primarily …

On The Challenges Of Modeling The Net Radiative Forcing Of Wetlands: Reconsidering Mitsch Et Al. 2013, Scott C. Neubauer

Biology Publications

Wetlands play a role in regulating global climate by removing carbon dioxide (CO2) from the atmosphere and sequestering it as soil carbon, and by emitting methane (CH4) and nitrous oxide (N2O) to the atmosphere. In a recent article in this journal (Mitsch et al. Landscape Ecol 28:583–597, 2013), CO2 sequestration and CH4 emissions were modeled for several freshwater wetlands that vary in vegetation type, climate, and hydrology. The authors of that study made significant errors that caused them to underestimate the importance of wetland CH4 emissions on climate dynamics. Here, I reanalyze the Mitsch et al. dataset and show that …

In Vitro Propagation Of Gentiana Scabra Bunge – An Important Medicinal Plant In The Chinese System Of Medicines, Shih-Hung Huang, Dinesh Chandra Agrawal, Fang-Sheng Wu, Hsin-Sheng Tsay

Biology Publications

Background: Gentiana scabra Bunge commonly known as `Long dan cao' in China has been used in traditional Chinese medicines for more than 2000 years. Dry roots and rhizome of the herb have been used for the treatment of inflammation, anorexia, indigestion and gastric infections. Iridoids and secoiridoids are the main bioactive compounds which attribute to the pharmacological properties of this plant. The species is difficult to mass propagate by seed due to the low percentage of germination and limited dormancy period. Wild populations in some locations are considered to be in the endangered category due to over exploitation.

Results: In …

Reduction Of The Pectoral Spine And Girdle In Domesticated Channel Catfish Is Likely Caused By Changes In Selection Pressure, Michael L. Fine

Biology Publications

Locked pectoral spines of the Channel Catfish Ictalurus punctatus more than double the fish's width and complicate ingestion by gape-limited predators. The spine mates with the pectoral girdle, a robust structure that anchors the spine. This study demonstrates that both spine and girdle exhibit negative allometric growth and that pectoral spines and girdles are lighter in domesticated than in wild Channel Catfish. This finding could be explained by changes in selection pressure for spine growth during domestication or by an epigenetic effect in which exposure to predators in wild fish stimulates pectoral growth. We tested the epigenetic hypothesis by exposing …

Spatiotemporal Variability And Sound Characterization In Silver Croaker Plagioscion Squamosissimus (Sciaenidae) In The Central Amazon, Alfredo Borie, Hin-Kiu Mok, Ning L. Chao, Michael L. Fine

Biology Publications

Background

The fish family Sciaenidae has numerous species that produce sounds with superfast muscles that vibrate the swimbladder. These muscles form post embryonically and undergo seasonal hypertrophy-atrophy cycles. The family has been the focus of numerous passive acoustic studies to localize spatial and temporal occurrence of spawning aggregations. Fishes produce disturbance calls when hand-held, and males form aggregations in late afternoon and produce advertisement calls to attract females for mating. Previous studies on five continents have been confined to temperate species. Here we examine the calls of the silver croakerPlagioscion squamosissimus, a freshwater equatorial species, which experiences constant …

A Macrophysiological Analysis Of Energetic Constraints On Geographic Range Size In Mammals, Salvatore J. Agosta, Joseph Bernado, Gerardo Ceballos, Michael A. Steele

Biology Publications

Physiological processes are essential for understanding the distribution and abundance of organisms, and recently, with widespread attention to climate change, physiology has been ushered back to the forefront of ecological thinking. We present a macrophysiological analysis of the energetics of geographic range size using combined data on body size, basal metabolic rate (BMR), phylogeny and range properties for 574 species of mammals. We propose three mechanisms by which interspecific variation in BMR should relate positively to geographic range size: (i) Thermal Plasticity Hypothesis, (ii) Activity Levels/Dispersal Hypothesis, and (iii) Energy Constraint Hypothesis. Although each mechanism predicts a positive correlation between …

Characterization And Generation Of Male Courtship Song In Cotesia Congregata (Hymenoptera: Braconidae), Justin P. Bredlau, Yasha J. Mohajer, Timothy M. Cameron, Karen M. Hester, Michael L. Fine

Biology Publications

Background

Male parasitic wasps attract females with a courtship song produced by rapid wing fanning. Songs have been described for several parasitic wasp species; however, beyond association with wing fanning, the mechanism of sound generation has not been examined. We characterized the male courtship song of Cotesia congregata (Hymenoptera: Braconidae) and investigated the biomechanics of sound production.

Methods and Principal Findings

Courtship songs were recorded using high-speed videography (2,000 fps) and audio recordings. The song consists of a long duration amplitude-modulated “buzz” followed by a series of pulsatile higher amplitude “boings,” each decaying into a terminal buzz followed by a …

Prey Responses To Predator Chemical Cues: Disentangling The Importance Of The Number And Biomass Of Prey Consumed, Michael W. Mccoy, Justin C. Touchon, Tobias Landberg, Karen M. Warkentin, James R. Vonesh

Biology Publications

To effectively balance investment in predator defenses versus other traits, organisms must accurately assess predation risk. Chemical cues caused by predation events are indicators of risk for prey in a wide variety of systems, but the relationship between how prey perceive risk in relation to the amount of prey consumed by predators is poorly understood. While per capita predation rate is often used as the metric of relative risk, studies aimed at quantifying predator-induced defenses commonly control biomass of prey consumed as the metric of risk. However, biomass consumed can change by altering either the number or size of prey …

An Intermediate In The Evolution Of Superfast Sonic Muscles., Hin-Kiu Mok, Eric Parmentier, Kuo-Hsun Chiu, Michael L. Fine

Biology Publications

Background

Intermediate forms in the evolution of new adaptations such as transitions from water to land and the evolution of flight are often poorly understood. Similarly, the evolution of superfast sonic muscles in fishes, often considered the fastest muscles in vertebrates, has been a mystery because slow bladder movement does not generate sound. Slow muscles that stretch the swimbladder and then produce sound during recoil have recently been discovered in ophidiiform fishes. Here we describe the disturbance call (produced when fish are held) and sonic mechanism in an unrelated perciform pearl perch (Glaucosomatidae) that represents an intermediate condition in the …