Biology Commons^™

Adrenocorticotropin Hormone Expression In The Developing Chicken Limb, Jodi F. Evans Ph.D., Michelle Vigliotti

Faculty Works: Biology, Chemistry, and Environmental Studies

In previous studies using mammalian models we have found both clinical and laboratory evidence of a role for melanocortins in endochondral ossification. The melanocortin system has remarkable conservation among vertebrates and melanocortin receptors are expressed with significant sequence homology in teleosts to mammals. The overall goal of these studies is to provide a more accessible model of melanocortin involvement in endochondral growth. We hope to determine if melanocortins play a role during endochondral ossification of the developing chicken limb. Like in mammals melanocortins are widely distributed throughout the body of chicken and participate in a wide range of physiological functions …

Locomotion In Response To Shifting Climate Zones: Not So Fast, Martin E. Feder, Theodore Garland Jr., James H. Marden, Anthony J. Zera

School of Biological Sciences: Faculty Publications

Although a species’ locomotor capacity is suggestive of its ability to escape global climate change, such a suggestion is not necessarily straightforward. Species vary substantially in locomotor capacity, both ontogenetically and within/among populations, and much of this variation has a genetic basis. Accordingly, locomotor capacity can and does evolve rapidly, as selection experiments demonstrate. Importantly, even though this evolution of locomotor capacity may be rapid enough to escape changing climate, genetic correlations among traits (often due to pleiotropy) are such that successful or rapid dispersers are often limited in colonization or reproductive ability, which may be viewed as a trade-off. …

Genetic Conflict And Sex Chromosome Evolution, Colin D. Meiklejohn, Yun Tao

School of Biological Sciences: Faculty Publications

Chromosomal sex determination systems create the opportunity for the evolution of selfish genetic elements that increase the transmission of one sex chromosome at the expense of its homolog. Because such selfish elements on sex chromosomes can reduce fertility and distort the sex ratio of progeny, unlinked suppressors are expected to evolve, bringing different regions of the genome into conflict over the meiotic transmission of the sex chromosomes. Here we argue that recurrent genetic conflict over sex chromosome transmission is an important evolutionary force that has shaped a wide range of seemingly disparate phenomena including the epigenetic regulation of genes expressed …

The Abl And Arg Non-Receptor Tyrosine Kinases Regulate Different Zones Of Stress Fiber, Focal Adhesion, And Contractile Network Localization In Spreading Fibroblasts, Justin G. Peacock, Brian A. Couch, Anthony J. Koleske

School of Biological Sciences: Faculty Publications

Directed cell migration requires precise spatial control of F-actin-based leading edge protrusion, focal adhesion (FA) dynamics, and actomyosin contractility. In spreading fibroblasts, the Abl family kinases, Abl and Arg, primarily localize to the nucleus and cell periphery, respectively. Here we provide evidence that Abl and Arg exert different spatial regulation on cellular contractile and adhesive structures. Loss of Abl function reduces FA, F-actin, and phosphorylated myosin light chain (pMLC) staining at the cell periphery, shifting the distribution of these elements more to the center of the cell than in wild-type (WT) and arg^—/— cells. Conversely, loss of Arg function …

Synaptic Clustering Of Psd-95 Is Regulated By C-Abl Through Tyrosine Phosphorylation, Karen Perez De Arce, Lorena Varela-Nallar, Olivia Farias, Alejandra Cifuentes, Paulina Bull, Brian A. Couch, Anthony J. Koleske, Nibaldo C. Inestrosa, Alejandra R. Alvarez

School of Biological Sciences: Faculty Publications

The c-Abl tyrosine kinase is present in mouse brain synapses, but its precise synaptic function is unknown. We found that c-Abl levels in the rat hippocampus increase postnatally, with expression peaking at the first postnatal week. In 14 d in vitro hippocampal neuron cultures, c-Abl localizes primarily to the postsynaptic compartment, in which it colocalizes with the postsynaptic scaffold protein postsynaptic density protein-95 (PSD-95) in apposition to presynaptic markers. c-Abl associates with PSD-95, and chemical or genetic inhibition of c-Abl kinase activity reduces PSD-95 tyrosine phosphorylation, leading to reduced PSD-95 clustering and reduced synapses in treated neurons. c-Abl can phosphorylate …

Neuronal Calcium Regulation And Cellular Stress In A Malignant Hyperthermia Disease Model, Jason Santiago

Electronic Theses and Dissertations

Calcium ions (Ca2+) are essential signaling molecules and must be carefully regulated to preserve specificity in function. One indispensible Ca2+ signaling protein is the ryanodine receptor (RyR) calcium release channel. RyR1 is essential for muscle contraction, and RyR1mutations can lead to severe muscle disorders such as malignant hyperthermia (MH). Recently, a mouse model of human MH (Y522S-RyR1) has been developed. In skeletal muscle, Y522S-RyR1 exhibits an increased sensitivity to activation resulting in Ca2+ leak, mitochondrial disorganization, and cellular stress. Although RyR1 expression is limited in the brain, the cerebellum may be particularly vulnerable to this disease because RyR1 is highly …

Investigating Instructors' Conceptions Of Evolution Through The Development Of The Classroom Test Of Evolutionary Reasoning, Patricia Eileen Palko

Electronic Theses and Dissertations

In order to assess the evolutionary understanding of high school biology teachers, an instrument entitled the Classroom Test of Evolutionary Reasoning (CTER) was developed. Content, response process, relations to another variable (the Conceptual Inventory of Natural Selection, or CINS), and internal structure evidence were compiled. The second version of the CTER was found to have adequate reliability and validity estimates to allow it to continue to be used as a measurement tool for an understanding of evolution. When assessing a sample of teachers (n = 724), the mean score was 6.35 out of a possible 13 points. The sample was …

Development Of A Fluorescent Anti-Factor Xa Assay To Monitor Unfractionated And Low Molecular Weight Heparins, Leanne Harris, Vanessa Castro-Lopez, Nissrin Hammadi, James S. O'Donnell, Tony Killard

Articles

Fluorogenic assays have many potential advantages over traditional clot-based and chromogenic assays such as the absence of interference from a range of factor deficiencies as well as offering the possibility of assays in platelet rich plasma or whole blood. A fluorogenic anti-factor Xa (anti-FXa) assay has been developed for the determination of heparin-like anticoagulants including unfractionated heparin (UFH), low-molecular weight heparins (LMWHs), namely enoxaparin and tinzaparin, and the synthetic heparinoid danaparoid, in commercial human pooled plasma. The assay was based on the complexation of heparin-spiked plasmas with exogenous FXa at a concentration of 4 nM in the presence of 0.9 …

Comparative Study Of Factor Xa Fluorogenic Substrates And Their Influence On The Quantification Of Lmwhs, Vanessa Castro-Lopez, Leanne F. Harris, James S. O'Donnell, Anthony J. Killard

Articles

Low molecular weight heparins (LMWHs) are recognised as the preferred anticoagulants in the prevention and treatment of venous thromboembolism. Anti-Factor Xa (anti-FXa) levels are used to monitor the anticoagulant effect of LMWHs and such assays are routinely employed in hospital diagnostic laboratories. In this study, a fluorogenic anti-FXa assay was developed using a commercially available fluorogenic substrate with an attached 6-amino-1- naphthalene-sulfonamide (ANSN) fluorophore and was used for the determination of two LMWHs, enoxaparin and tinzaparin and the heparinoid, danaparoid. The assay was based on the complexation of heparinised plasma with 100 nM exogenous FXa and 25 μM of the …

Structural Investigation Of Atp-Utilizing Enzymes: Structures Involved In H+ Homeostasis And The Proliferation Of Hormone-Dependent Cancers, Zacariah Louis Hildenbrand

Open Access Theses & Dissertations

ATP is a multifunctional nucleotide considered to be the "molecular unit of currency" of intracellular energy transfer. ATP is utilized ubiquitously for the transport of chemical energy within the cell in addition to acting as a substrate in the regulation of many metabolic and signaling transduction pathways such as kinase-mediated signaling cascades. Interestingly, the functional mechanisms of many enzymes require the binding of ATP to trigger key structural and conformational changes that ultimately result in enzyme-directed catalysis. Two of the most omnipresent ATPases within the cell include the V-ATPase rotary proton pump and the Hsp90 protein-folding chaperone. Structural and biochemical …

Fabrication Of Miniature Drug Screening Platform Using Low Cost Bioprinting Technology, Jorge Ivan Rodriguez

Open Access Theses & Dissertations

In the pharmaceutical industry, new chemicals and substances are being tested to find appropriate compounds or mix for treating a specific disease. The demand for screening large compound collections against and increasing number of therapeutic targets has stimulated technology development in the areas of assay automation and miniaturization. Current methods for evaluating the reactions of cells use a volume in the range of microliters. We have developed a new and low-cost deposition method to fabricate miniature drug screening platform that can realistically and inexpensively evaluate biochemical reactions up to 4 substances per trial in a picoliter-scale volume. This paper describes …

Trapping Mammals In A Cautious World: The Effect Of Disinfectants On Trap Success, James Wilson, K. E. Mabry

Biology Faculty Publications

Disinfecting traps that have captured small mammals is one recommendation for preventing occurrence of hantavirus infection; however, the potential effects of disinfection on small mammal trappability have not been investigated thoroughly. We conducted an experiment to compare the effects of 2 disinfectants (Lysol® and household bleach) on the trappability of 4 small mammal species (Peromyscus maniculatus, Neotamias spp., and Spermophilus lateralis). We established triplicate trap grids in 2 forest types (red fir and mixed conifer), each consisting of a 6 × 6 array of Sherman live-traps placed at 10-m intervals. Traps were given 1 of 3 treatments: control (water), Lysol, …

Merits And Limits Of Ecosystem Protection For Conserving Wild Salmon In A Northern Coastal British Columbia River, Aaron C. Hill, Thomas S. Bansak, Bonnie K. Ellis, Jack Arthur Stanford

Biological Sciences Faculty Publications

Loss and degradation of freshwater habitat reduces the ability of wild salmon populations to endure other anthropogenic stressors such as climate change, harvest, and interactions with artificially propagated fishes. Preservation of pristine salmon rivers has thus been advocated as a cost-effective way of sustaining wild Pacific salmon populations. We examine the value of freshwater habitat protection in conserving salmon and fostering resilience in the Kitlope watershed in northern coastal British Columbia—a large (3186 km²) and undeveloped temperate rainforest ecosystem with legislated protected status. In comparison with other pristine Pacific Rim salmon rivers we studied, the Kitlope is characterized …

Small-Mammal Seed Predation Limits The Recruitment And Abundance Of Two Perennial Grassland Forbs, Mary Bricker, Dean Pearson, John L. Maron

Biological Sciences Faculty Publications

Although post-dispersal seed predators are common and often reduce seed density, their influence on plant population abundance remains unclear. On the one hand, increasing evidence suggests that many plant populations are seed limited, implying that seed predators could reduce plant abundance. On the other hand, it is generally uncertain whether the magnitude of seed limitation imposed by granivores is strong enough to overcome density-dependent processes that could compensate for seed loss at later stages. We examined the impact of seed predation by small mammals, primarily deer mice (Peromyscus maniculatus), on seedling recruitment and subsequent plant establishment of two …

Are Forested Buffers An Effective Conservation Strategy For Riparian Fauna? An Assessment Using Meta-Analysis, Laurie B. Marczak, Takashi Sakamaki, Shannon L. Turvey, Isabelle Deguise, Sylvia L. R. Wood, John S. Richardson

Biological Sciences Faculty Publications

Historically, forested riparian buffers have been created to provide protection for aquatic organisms and aquatic ecosystem functions. Increasingly, new and existing riparian buffers are being used also to meet terrestrial conservation requirements. To test the effectiveness of riparian buffers for conserving terrestrial fauna, we conducted a meta-analysis using published data from 397 comparisons of species abundance in riparian buffers and unharvested (reference) riparian sites. The response of terrestrial species to riparian buffers was not consistent between taxonomic groups; bird and arthropod abundances were significantly greater in buffers relative to unharvested areas, whereas amphibian abundance decreased. Edge-preferring species were more abundant …

Arthropod Biodiversity In Response To The Restoration Of Former Pine Plantations, John Curtis Burkhalter

UNF Graduate Theses and Dissertations

The goal of ecological restoration is to return degraded or altered ecosystems to their pre-disturbed state with respect to ecosystem structure, function, and composition. In the current study the research objective was to reestablish high levels of biodiversity on two restored pine plantations as well as restore a native pine flatwoods ecosystem. Managed, even-aged pine flatwoods are now the most extensive ecosystem in North Florida, comprising approximately 70% of the forested landscape. Slash pine trees were thinned in the experimental plots to restore the natural slash pine density of native ecosystems. In addition to the thinning treatments, experimental plots have …

Transepithelial D-Glucose And D-Fructose Transport Across Lobster Intestine, Ijeoma Ebelechukwu Obi

UNF Graduate Theses and Dissertations

The mechanisms of transepithelial absorption of dietary D-glucose and D-fructose in the American lobster, Homarus americanus, were investigated in this study in order to determine whether sugar transport proteins have been conserved throughout evolution. Whole lobster intestine was isolated and mounted in a perfusion chamber to determine transepithelial mucosal to serosal (MS) and serosal to mucosal (SM) mechanisms of ³H-D-glucose and ³H-D-fructose transport across the intestine. Unidirectional MS and SM fluxes were measured by adding variable concentrations of ³H-D-glucose and ³H-D-fructose (2.5 to 50uM) to either the perfusate or the bath respectively and sampling the …

Kinetics Of Hedgehog-Dependent Full-Length Gli3 Accumulation In Primary Cilia And Subsequent Degradation, Xiaohui Wen, Cary Lai, Marie Evangelista, Jo-Anne Hongo, Frederic J. De Sauvage, Suzie J. Scales

Biology Faculty Publications

Hedgehog (Hh) signaling in vertebrates depends on intraflagellar transport (IFT) within primary cilia. The Hh receptor Patched is found in cilia in the absence of Hh and is replaced by the signal transducer Smoothened within an hour of Hh stimulation. By generating antibodies capable of detecting endogenous pathway transcription factors Gli2 and Gli3, we monitored their kinetics of accumulation in cilia upon Hh stimulation. Localization occurs within minutes of Hh addition, making it the fastest reported readout of pathway activity, which permits more precise temporal and spatial localization of Hh signaling events. We show that the species of Gli3 that …

Acoel And Platyhelminth Models For Stem-Cell Research, A. E. Bely, James M. Sikes Ph.D.

Biology Faculty Publications

Acoel and platyhelminth worms are particularly attractive invertebrate models for stem-cell research because their bodies are continually renewed from large pools of somatic stem cells. Several recent studies, including one in BMC Developmental Biology, are beginning to reveal the cellular dynamics and molecular basis of stem-cell function in these animals.

See research article http://www.biomedcentral.com/1471-213X/9/69.

Adult somatic stem cells can play critical roles in postembryonic developmental processes such as tissue renewal, growth, repair, and regeneration [1]. Understanding how such cells are maintained and produce differentiated progeny is thus of general interest in developmental biology, in addition to …

A Spectrographic Analysis Of American Kestrel (Falco Sparverius) Vocalizations : Do Broodmates Sound More Like Each Other Than Non-Related Broods?, Erica Gloria Mueller

Theses, Dissertations and Culminating Projects

Using spectrographic analysis, I studied the vocalizations of American Kestrel (Falco sparverius) chicks to determine if siblings sounded more like each other than nonrelated chicks. I also performed a feasibility study on obtaining and analyzing vocalizations of wild adult kestrels. A total of 144 vocal recordings was obtained from 67 female and 77 male kestrel chicks in the 2005 and 2006 kestrel breeding seasons. Sixteen adult kestrel vocal samples were also obtained from eleven females and five males, each a parent to one of the broods that were audio-recorded.

Fifteen vocal parameters were analyzed through spectrographic analysis for each individual …