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- Title
- Approaches for raising the level of FOXO3a in animal cells.
- Creator
- Navarro, Diana., Charles E. Schmidt College of Medicine, Department of Biomedical Science
- Abstract/Description
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The turtle is a unique model of anoxic survival. The turtle's brain can tolerate total oxygen deprivation for hours to days as well as prevent high levels of mitochondrial-derived free radicals upon re-oxygenation. Because of its ability to prevent elevated free radical generation, the turtle has also become recognized as a model of exceptional longevity. We are employing the turtle model for an investigation into the regulation of a key antioxidant enzyme system - methionine sulfoxide...
Show moreThe turtle is a unique model of anoxic survival. The turtle's brain can tolerate total oxygen deprivation for hours to days as well as prevent high levels of mitochondrial-derived free radicals upon re-oxygenation. Because of its ability to prevent elevated free radical generation, the turtle has also become recognized as a model of exceptional longevity. We are employing the turtle model for an investigation into the regulation of a key antioxidant enzyme system - methionine sulfoxide reductases (Msrs), primarily MsrA and MsrB. The Msr system is capable of reversing oxidation of methionines in proteins and Msr subtypes have been implicated in protecting tissues against oxidative stress, as well as, enhancing the longevity of organisms from yeast to mammals. Preliminary data, unpublished results, indicate that MsrA protein and transcripts are elevated by anoxia. A recent study on Caenorhabditis elegans demonstrated that FOXO is involved in activation of the MsrA promoter. Using the turtle MsrA promoter sequence we worked to determine which regions in the promoter are necessary for activation by anoxia. The results of the present study were 1) to prepare a TAT-FOXO3a fusion protein which could penetrate animal cells and 2) to construct a FOXO3a expression vector for transcription studies on MsrA expression.
Show less - Date Issued
- 2012
- PURL
- http://purl.flvc.org/FAU/3342243
- Subject Headings
- Cellular signal transduction, Cell proliferation, Oxidative stress, Prevention, Adaptation (Physiology)
- Format
- Document (PDF)
- Title
- Hydrodynamic functions of the wing-shaped heads of hammerhead sharks.
- Creator
- Barousse, Julien., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
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The hydrodynamics of three different shark heads: Eusphyra blochii (Winghead shark), Carcharhinus acronotus (Blacknose shark) and Sphyrna tiburo (Bonnethead shark) were investigated. Force transducer measurement was used to explore how the cephalofoil (wing-shaped head) affects maneuverability and efficiency. As the dynamic behavior of maneuvering wings differs from that of the steady state motion, experiments have been conducted to simulate: 1) steady-state (no yaw motion) constant velocity...
Show moreThe hydrodynamics of three different shark heads: Eusphyra blochii (Winghead shark), Carcharhinus acronotus (Blacknose shark) and Sphyrna tiburo (Bonnethead shark) were investigated. Force transducer measurement was used to explore how the cephalofoil (wing-shaped head) affects maneuverability and efficiency. As the dynamic behavior of maneuvering wings differs from that of the steady state motion, experiments have been conducted to simulate: 1) steady-state (no yaw motion) constant velocity swimming, 2) constant forward velocity with yawing motion of the head and 3) turning maneuvers. Different range of velocities, angle of attack, yaw frequency and yaw amplitude were tested. Drag and lift coefficients were calculated and compared. The lift coefficient of Winghead shark is much higher compared to the other sharks. The lift-to-drag ratio showed that the Winghead shark has a hydrodynamic advantage compared to Blacknose shark and Bonnethead shark.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/2795459
- Subject Headings
- Aquatic animals (Physiology), Adaptation (Biology), Sharks, Locomotion, Predation (Biology)
- Format
- Document (PDF)
- Title
- Ecomorphology of Shark Electroreceptors.
- Creator
- Cornett, Anthony D., Kajiura, Stephen M., Florida Atlantic University
- Abstract/Description
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Sharks possess an electrosensory system which allows the detection of electric fields . How this system varies among related taxa and among species inhabiting different environments remains unexplored. Electroreceptor number was quantified for representative species of related taxa (genera, families, orders) from different environments (pelagic, coastal, deepwater) and taxa from similar environments to determine potential phylogenetic constraint or evolutionary convergence. Coastal open water...
Show moreSharks possess an electrosensory system which allows the detection of electric fields . How this system varies among related taxa and among species inhabiting different environments remains unexplored. Electroreceptor number was quantified for representative species of related taxa (genera, families, orders) from different environments (pelagic, coastal, deepwater) and taxa from similar environments to determine potential phylogenetic constraint or evolutionary convergence. Coastal open water sharks possess the greatest number of electroreceptors; deepwater sharks the least. Pelagic and coastal benthic sharks retain comparable electrosensory pore numbers despite inhabiting vastly different environments. Electrosensory pores were primarily located in ventral distributions, except among coastal open water sharks which possess roughly even distributions around the head. Among related species and genera, pore numbers and distribution are comparable, with greater variation among higher taxa. Results implicate evolutionary convergence as the primary influence in electroreceptor development, while phylogenetic constraint establishes similar base values for number and distribution.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fau/fd/FA00000737
- Subject Headings
- Sharks--Ecology, Sharks--Morphology, Echolocation (Physiology), Aquatic animals--Physiology, Senses and sensation, Adaptation (Biology)
- Format
- Document (PDF)
- Title
- A Novel Interaction: The thin stripe hermit Crab, Clibanarius vittatus, kills the Florida crown conch, Melongena corona, for its shell.
- Creator
- Cutter, Jennifer, Devlin, Donna, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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The hermit crab Clibanarius vittatus kills Melongena corona solely to acquire a better fitting shell. This finding is contrary to previous studies, which found that hermit crabs of other species cannot kill gastropods or, in most instances, remove freshly dead gastropods from their shells. This interaction cannot be classified as predation because Melongena tissue was never consumed. Clibanarius killed Melongena only when by doing so they could trade up to a better fitting shell. It cannot be...
Show moreThe hermit crab Clibanarius vittatus kills Melongena corona solely to acquire a better fitting shell. This finding is contrary to previous studies, which found that hermit crabs of other species cannot kill gastropods or, in most instances, remove freshly dead gastropods from their shells. This interaction cannot be classified as predation because Melongena tissue was never consumed. Clibanarius killed Melongena only when by doing so they could trade up to a better fitting shell. It cannot be classified as competition because there is no opportunity for Melongena to gain from the interaction. Therefore the term “lethal eviction” is hereby proposed for this interaction. The ability to kill a gastropod to obtain a superior shell gives Clibanarius vittatus an evolutionary advantage over other hermit crab species. It is not known if the outcome of this interaction is widespread where both species occur or if it is confined to the study area.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004925, http://purl.flvc.org/fau/fd/FA00004925
- Subject Headings
- Crabs--Behavior., Crab culture., Predation (Biology), Adaptation (Physiology), Aquatic ecology., Intertidal ecology., Conservation biology.
- Format
- Document (PDF)
- Title
- Cognitive and magnetosensory ecology of the yellow stingray, Urobatis jamaicensis.
- Creator
- Newton, Kyle C., Kajiura, Stephen M., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Elasmobranchs (sharks, skates, and rays) migrate across a wide range of spatiotemporal scales, display philopatry, seasonal residency, and maintain home ranges. Many animals use the Earth’s magnetic field to orient and navigate between habitats. The geomagnetic field provides a variety of sensory cues to magnetically sensitive species, which could potentially use the polarity, or intensity and inclination angle of the field, to derive a sense of direction, or location, during migration....
Show moreElasmobranchs (sharks, skates, and rays) migrate across a wide range of spatiotemporal scales, display philopatry, seasonal residency, and maintain home ranges. Many animals use the Earth’s magnetic field to orient and navigate between habitats. The geomagnetic field provides a variety of sensory cues to magnetically sensitive species, which could potentially use the polarity, or intensity and inclination angle of the field, to derive a sense of direction, or location, during migration. Magnetoreception has never been unequivocally demonstrated in any elasmobranch species and the cognitive abilities of these fishes are poorly studied. This project used behavioral conditioning assays that paired magnetic and reinforcement stimuli in order to elicit behavioral responses. The specific goals were to determine if the yellow stingray, Urobatis jamaicensis, could detect magnetic fields, to quantify the nature of the magnetic stimuli it could detect, and to quantify the learning and memory capabilities of this species. The results supported the original hypotheses and demonstrated that the yellow stingray could: discriminate between magnetic and non-magnetic objects; detect and discriminate between changes in geomagnetic field strength and inclination angle; and use geomagnetic field polarity to solve a navigational task. The yellow stingray learned behavioral tasks faster and retained the memories of learned associations longer than any batoid (skate or ray) to date. The data also suggest that this species can classify magnetic field stimuli into categories and learn similar behavioral tasks with increased efficiency, which indicate behavioral flexibility. These data support the idea that cartilaginous fishes use the geomagnetic field as an environmental cue to derive a sense of location and direction during migrations. Future studies should investigate the mechanism, physiological threshold, and sensitivity range of the elasmobranch magnetic sense in order to understand the effects of anthropogenic activities and environmental change on the migratory ability of these fishes.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004883, http://purl.flvc.org/fau/fd/FA00004883
- Subject Headings
- Animal behavior., Animal migration., Magnetic fields--Physiological effect., Senses and sensation., Adaptation (Biology)
- Format
- Document (PDF)
- Title
- Effects of stressors on differential gene expression and secondary metabolites by Axinella corrugata.
- Creator
- Grima, Jennifer., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Sponges are an important source of bioactive marine natural products, or secondary metabolites. The common Caribbean reef sponge, Axinella corrugata, produces an antitumor and antibacterial chemical, stevensine. This study determined whether environmental stressors, such as elevated temperature and exposure to Amphibalanus amphitrite larvae, affect the production of stevensine by A.corrugata and if the stressors caused A.corrugata to exhibit differential gene expression. Temperature stress...
Show moreSponges are an important source of bioactive marine natural products, or secondary metabolites. The common Caribbean reef sponge, Axinella corrugata, produces an antitumor and antibacterial chemical, stevensine. This study determined whether environmental stressors, such as elevated temperature and exposure to Amphibalanus amphitrite larvae, affect the production of stevensine by A.corrugata and if the stressors caused A.corrugata to exhibit differential gene expression. Temperature stress resulted in no significant change in the production of stevensine; only two genes were significantly differentially expressed, including hsp70. Larval stressed resulted in increased production of stevensine and significant differential gene expression (more than seventy genes). This study suggests that A.corrugata may be resilient to elevations in temperature and that one of stevensine's roles in nature is as an antifoulant.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3360781
- Subject Headings
- Axinellida, Sponges, Marine pharmacology, Adaptation (Biology), Gene expression, Genetic regulation, Stress (Physiology), Ecophysiology
- Format
- Document (PDF)
- Title
- Specific dynamic action in hatchling and post-hatchling green (Chelonia mydas) and loggerhead (Caretta caretta ) sea turtles.
- Creator
- Kowalski, Amy, Florida Atlantic University, Milton, Sarah L., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Specific dynamic action (SDA) describes a post-feeding increase in oxygen consumption where most energy derived from food is allocated to post-absorptive processes, including growth and maintenance. SDA and growth in hatchling sea turtles is of special interest because they experience drastic changes in diet, oxygen availability and habitat during the first several months of life. This study investigated SDA variation between species and among age groups. SDA was quantified in two species of...
Show moreSpecific dynamic action (SDA) describes a post-feeding increase in oxygen consumption where most energy derived from food is allocated to post-absorptive processes, including growth and maintenance. SDA and growth in hatchling sea turtles is of special interest because they experience drastic changes in diet, oxygen availability and habitat during the first several months of life. This study investigated SDA variation between species and among age groups. SDA was quantified in two species of sea turtle (Chelonia mydas, Caretta caretta) at 7, 30, 60, & 90 days post-hatching. Turtles were fed a known amount of food, and oxygen consumption was monitored using a metabolic chamber. SDA percentage of total energy did not increase with age (species pooled), although magnitude of SDA was higher in C. mydas when compared to C. caretta (ages pooled). These results imply that SDA does not increase proportionally with age, and that hatchling C. mydas use more absolute energy for SDA than C. caretta .
Show less - Date Issued
- 2005
- PURL
- http://purl.flvc.org/fcla/dt/13283
- Subject Headings
- Adaptation (Biology), Sea turtles--Feeding and feeds, Physiology, Comparative, Sea turtles--Ecology
- Format
- Document (PDF)
- Title
- A comparison of the ontogeny of energy consumption in leatherback, Dermochelys coriacea and olive ridley, Lepidochelys olivacea sea turtle hatchlings.
- Creator
- Jones, T. Todd, Florida Atlantic University, Lutz, Peter L., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Changes in activity related oxygen consumption and energy partitioning were measured in leatherback and olive ridley sea turtle hatchlings over their first month after nest emergence. Leatherbacks emerge with about 75--90 KJ of energy in the residual yolk at their disposal for growth and movement. In comparison, the residual yolk energy reserves for the olive ridley are estimated to be much less (45 KJ). In leatherbacks resting specific oxygen consumption rates decreased by 53% over the first...
Show moreChanges in activity related oxygen consumption and energy partitioning were measured in leatherback and olive ridley sea turtle hatchlings over their first month after nest emergence. Leatherbacks emerge with about 75--90 KJ of energy in the residual yolk at their disposal for growth and movement. In comparison, the residual yolk energy reserves for the olive ridley are estimated to be much less (45 KJ). In leatherbacks resting specific oxygen consumption rates decreased by 53% over the first post-hatching month (0.0065 ml O2 min-1 g-1--0.0031 ml O2 min-1 g-1), while for ridleys the fall was 32% (0.0038 ml O2 min-1 g-1--0.0026 ml O2 min-1 g-1). Greater differences were seen in aerobic scope. For olive ridleys the factorial aerobic scope doubled over the first month but there was no significant increase in the leatherback's factorial aerobic scope. Leatherback hatchlings gained on average 33% body mass (10 g) over the first week however 70 to 80% of this increase was due to water accumulation. The differences in aerobic scope and energy reserves are related to differences in early life ecological stratagems of these species.
Show less - Date Issued
- 2004
- PURL
- http://purl.flvc.org/fcla/dt/13139
- Subject Headings
- Sea turtles--Ecology, Animal behavior, Ontogeny, Developmental biology, Adaptation (Physiology), Ecophysiology
- Format
- Document (PDF)
- Title
- Effect of Deepwater Horizon Crude Oil on Olfaction and Electroreception in the Atlantic Stingray, Dasyatis sabina.
- Creator
- Cave, Eloise, Kajiura, Stephen M., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Crude oil causes both lethal and sublethal effects on marine organisms, but the impact upon sensory function remains unexplored. Elasmobranchs rely upon the effective functioning of their sensory systems for use in feeding, mating, and predator avoidance. The objective of this study was to test the effect of crude oil upon the olfactory and electroreceptive sensitivity of the Atlantic stingray, Dasyatis sabina. The magnitudes of the electro-olfactogram (EOG) responses were significantly...
Show moreCrude oil causes both lethal and sublethal effects on marine organisms, but the impact upon sensory function remains unexplored. Elasmobranchs rely upon the effective functioning of their sensory systems for use in feeding, mating, and predator avoidance. The objective of this study was to test the effect of crude oil upon the olfactory and electroreceptive sensitivity of the Atlantic stingray, Dasyatis sabina. The magnitudes of the electro-olfactogram (EOG) responses were significantly depressed by 26% (Glutamic Acid) to 157% (Cysteine) for all amino acids when stingrays were exposed to crude oil. The shapes of the EOG responses when exposed to oil were also significantly different, exhibiting a more protracted response compared to un-exposed stingrays. Oil exposed stingrays exhibited a significant decrease in orientation distance to prey-simulating electric fields. This study is the first to quantify the effects of crude oil on olfactory and electrosensory sensitivity of marine predators.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004776, http://purl.flvc.org/fau/fd/FA00004776
- Subject Headings
- BP Deepwater Horizon Explosion and Oil Spill, 2010., Stingrays--Physiology., Deep-sea biology., Adaptation (Biology), Electroreceptors., Oil spills--Environmental aspects., Olfactometry.
- Format
- Document (PDF)