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- Title
- Broad Application of Conotoxins As Molecular Probes, Therapeutic Leads and Drug Delivery Vectors In Excitable and Non-Excitable Systems.
- Creator
- Padilla, Alberto, Hartmann, James X., Mari, Frank, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Conotoxins are peptides expressed by the exogenome of more than 800 species of marine mollusks belonging to the genus Conus (cone snails.) Owing to their high specificity and affinity for ion channels, transporter molecules, and cell receptors of the central and peripheral nervous systems, conotoxins have been investigated for nearly four decades. These efforts on conotoxin research made possible the FDA approved use of Ziconitide/Prialt, a conotoxin derived from the venom of Conus magus,...
Show moreConotoxins are peptides expressed by the exogenome of more than 800 species of marine mollusks belonging to the genus Conus (cone snails.) Owing to their high specificity and affinity for ion channels, transporter molecules, and cell receptors of the central and peripheral nervous systems, conotoxins have been investigated for nearly four decades. These efforts on conotoxin research made possible the FDA approved use of Ziconitide/Prialt, a conotoxin derived from the venom of Conus magus, which effectively treats patients suffering from severe chronic pain without consequent narcotic effects. Additionally, six other conotoxins have reached clinical trials and many novel ones are being discovered every day. Investigations reported in this dissertation broadens the applicability of conotoxins to non-excitable systems. Here, conotoxins from the dissected venom of the vermivorous cone snail Conus nux were isolated and purified by size exclusion and reverse phase HPLC and characterized by MALDI-TOF and MS/MS spectrometry. The purified conopeptide fractions revealed: 1) antagonist activity of conotoxin NuxVID on two human voltage-gated sodium channels, displaying capabilities as a practical molecular probe and a potential therapeutic lead. 2) Ability for two novel conotoxins to traverse artificial biological membranes, suggesting their potential as drug delivery systems. 3) In vitro capacity of several novel conopeptides to interfere with the adhesion of PfEMP1 domains, expressed in P. falciparum infected erythrocytes, to vascular endothelial and placenta receptors. Lastly, this work reveals binding of the synthetic form of α-conotoxin ImI, from the vermivorous cone snail Conus imperialis, to the α7 nAChR of macrophage-like-cells derived from the pre-monocytic leukemic cell line THP-1 in support of the involvement of this receptor in the cholinergic anti-inflammatory pathway.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013250
- Subject Headings
- Conotoxins, Drug Delivery Systems, Molecular Probes
- Format
- Document (PDF)
- Title
- Impact of the Fire Ant Pesticide Hydramethylnon (AMDRO®) on Loggerhead Sea Turtle Reproductive Success and Hatchling Quality.
- Creator
- Smith, Heather, Salmon, Michael, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Invasive fire ants are aggressive predators of ground nesting birds and reptiles and are spreading rapidly throughout tropical and temperate climates. Fire ants have been known to prey on a variety of reptile species, including threatened loggerhead sea turtles. The granular fire ant bait AMDRO® is being used on sea turtle nesting beaches to protect nests and hatchlings from these predators, however no studies have been conducted to thoroughly assess its effect on any reptile species. In this...
Show moreInvasive fire ants are aggressive predators of ground nesting birds and reptiles and are spreading rapidly throughout tropical and temperate climates. Fire ants have been known to prey on a variety of reptile species, including threatened loggerhead sea turtles. The granular fire ant bait AMDRO® is being used on sea turtle nesting beaches to protect nests and hatchlings from these predators, however no studies have been conducted to thoroughly assess its effect on any reptile species. In this field study, I examined the impact of AMDRO® on hatching and emergence success, body condition, and orientation behavior in loggerhead sea turtles (Caretta caretta) in Juno Beach, Florida, USA. Pesticide granules were placed in a one-foot diameter circle directly above nest chambers during the final 5-10 days of incubation, which is representative of typical field applications of this pesticide on nesting beaches. Two controls were used in this study: cornmeal granules in soybean oil served as the vehicle control, and a second group of untreated control nests were left to incubate naturally, undisturbed. After a natural emergence, hatchlings were collected to calculate a body condition index (BCI). For a subset of the nests, 20 hatchlings were collected to perform orientation assays to assess the hatchlings’ ability to orient correctly toward the ocean, a visually mediated process that could be altered by visual impairments resulting from ADMRO® exposure. Three days following a mass emergence event, nests were excavated to collect hatching and emergence success data. Sand samples were collected to determine if the toxicant persisted in the environment or penetrated the egg chamber. Analyses indicated that the toxicant had no effect on hatchling morphology, hatching success, or emergence success. It also had no effect on the ability of hatchlings to orient toward the ocean. However, the pesticide granules attracted more predators than were seen at control nests. Thus, while AMDRO® might not directly impact reproductive success or hatchling behavior, it had the unanticipated effect of possibly increasing nest vulnerability to predators.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013264
- Subject Headings
- Fire ants, Loggerhead turtle--Effect of pesticides on, Caretta caretta
- Format
- Document (PDF)
- Title
- Analysis of SLKED gene expression in CRISPR/Cas9-mediated gene knockouts in Tomato (Micro-Tom).
- Creator
- Vichyavichien, Paveena, Zhang, Xing-Hai, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Clustered regularly interspaced short palindromic repeats (CRISPR/CRISPR-associated (Cas) protein system, CRISPR/Cas9, uses single-guide RNA to guide Cas9 to the target site for genome editing. In this study, the CRISPR/Cas9 system was used to knockout KED in tomato (Solanum lycopersicum). KED was first identified while screening the wounded tobacco (Nicotiana tabacum) leaves. We found that alignment of the protein sequence of SlKED (Solanum lycopersicum KED) and NtKED (Nicotiana tabacum KED)...
Show moreClustered regularly interspaced short palindromic repeats (CRISPR/CRISPR-associated (Cas) protein system, CRISPR/Cas9, uses single-guide RNA to guide Cas9 to the target site for genome editing. In this study, the CRISPR/Cas9 system was used to knockout KED in tomato (Solanum lycopersicum). KED was first identified while screening the wounded tobacco (Nicotiana tabacum) leaves. We found that alignment of the protein sequence of SlKED (Solanum lycopersicum KED) and NtKED (Nicotiana tabacum KED) showed 55.1% identity. To investigate, we generated SlKED knockout tomato plants with a single base pair deletion, a five base pair deletion and a three base pair deletion with a single base pair insertion. We performed wounding assays and analyzed gene expression and found that the wounded SlKED knockout plant showed no gene induction. Furthermore, the biological assay results revealed that the tobacco hornworm (Manduca sexta) gained more mass when fed on the SlKED knockout plant. Our studies show that the KED gene plays a role in wound-induced mechanism and suggested it may involve in the plant defense system against biological stress and insect feeding.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013275
- Subject Headings
- Genome editing, Gene expression, CRISPR/Cas9, CRISPR-associated protein 9
- Format
- Document (PDF)
- Title
- Measuring Nest-to-Surf Mortality of Florida’s East and West Coast Loggerhead Sea Turtle (Caretta caretta) Hatchlings.
- Creator
- Villegas Vindiola, Brianna, Wyneken, Jeanette, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Sea turtle hatchlings emerge from their nest and quickly crawl to the surf. During the crawl, hatchlings may encounter threats, biotic and abiotic, which can affect their ability to successfully reach the surf. The impact of these threats on hatchling survival during that crawl is largely undocumented. Current methods used to estimate cohort recruitment rely heavily on nest inventory data. This method, however, does not account for post-emergent hatchling mortality that occurs during the...
Show moreSea turtle hatchlings emerge from their nest and quickly crawl to the surf. During the crawl, hatchlings may encounter threats, biotic and abiotic, which can affect their ability to successfully reach the surf. The impact of these threats on hatchling survival during that crawl is largely undocumented. Current methods used to estimate cohort recruitment rely heavily on nest inventory data. This method, however, does not account for post-emergent hatchling mortality that occurs during the crawl. During the 2017-2018 nesting seasons, I quantified the fates of 1,379 loggerhead (Caretta caretta) hatchlings from 26 nest emergences during their crawl from the nest to the surf on the east and west coasts of Florida. I documented hatchling fates at 5 Florida nesting beaches: Wabasso, Boca Raton, Keewaydin Island, Naples, and Anna Maria Island. Overall, 6.5% of all emergent hatchlings died during the crawl from the nests to the surf. Ghost crabs, night herons, foxes, and coyotes killed hatchlings and photopollution and barriers on the beach (both abiotic threats) caused hatchling mortality. Anthropogenic (abiotic) threats accounted for more mortality than did predators. In order to assess how beach urbanization impacts hatchling mortality, I categorized each study site as urban (Wabasso and Naples), intermediate (Anna Maria Island and Boca Raton), or natural (Keewaydin Island) based on the relative levels of shoreline development and human activity at each beach. Sites with intermediate levels of urbanization accounted for greater levels of hatchling mortality than at other beaches due to the absolutely larger numbers of hatchlings lost to a disorientation event and to a beach barrier. Given the small numbers of emergences, at all sites, only a small proportion of the hatchlings mortalities (e.g., between 3 and 12 percent), site type could not be rigorously used as a discriminator. My results provide a better understanding of how specific environmental threats contribute to hatchling mortality. While nest-to-surf mortality is relatively low, its cumulative costs add up to several hundreds of thousands of hatchlings. Armed with this information, nesting beach managers can assess risks and focus their efforts to implement the most effective management practices to minimize losses of this imperiled species.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013277
- Subject Headings
- Loggerhead turtle--Florida, Caretta caretta, Sea turtles--Nests, Sea turtles--Mortality
- Format
- Document (PDF)
- Title
- An Introduced Primate Species, Chlorocebus Sabaeus, in Dania Beach, Florida: Investigating Origins, Demographics, and Anthropogenic Implications of an Established Population.
- Creator
- Williams, Deborah M., Detwiler, Kate, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Nonnative species are reshaping global ecosystems. The success of a nonnative species hinges on both biological and cultural variables. Primates represent a minority of nonnative species but warrant research to understand ecological implications and management solutions. The Florida Fish and Wildlife Conservation Commission recognizes three species of nonnative primates in Florida that include populations of rhesus macaques (Macaca mulatta) in Marion County, squirrel monkeys (Saimiri spp.) in...
Show moreNonnative species are reshaping global ecosystems. The success of a nonnative species hinges on both biological and cultural variables. Primates represent a minority of nonnative species but warrant research to understand ecological implications and management solutions. The Florida Fish and Wildlife Conservation Commission recognizes three species of nonnative primates in Florida that include populations of rhesus macaques (Macaca mulatta) in Marion County, squirrel monkeys (Saimiri spp.) in Broward County, and green monkeys (Chlorocebus sabaeus) in Broward County. This study focused on the Dania Beach C. sabaeus population. The goals of this study were to: 1) determine the geographical origins and species of the monkeys, 2) record demographics and determine population growth rate, 3) assess the public’s perception of monkeys, and 4) understand the influence of human provisioning on the population’s behavior and biology. Public surveys and direct field observations of social groups provided baseline data to show that unlike other introduced primates (e.g., macaques in Marion County and green monkeys in the Caribbean), the Dania Beach monkey population has strong public support and is at risk of extinction within the next 100 years.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013279
- Subject Headings
- Nonnative species, Green monkey, Dania Beach (Fla.), Introduced species
- Format
- Document (PDF)
- Title
- Hatchling sex ratios and nest temperature-sex ratio response of three South Florida marine turtle species (Caretta caretta L., Chelona mydas L., and Dermochelys coriacea V.).
- Creator
- Rogers, Micah Marie., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
South Florida's loggerhead (Caretta caretta), green (Chelonia mydas) and leatherback (Dermochelys coriacea) sea turtles hatchling have environmentally determined sex. The in situ nest mean hatchling sex ratios (SR) were highly female-biased : loggerhead F=0.89) and green turtle F=0.81; leatherback's SR was nearly balanced (0.55F). Nest temperatures and SRs differed between leatherbacks and loggerhead and green turtles. The latter two did not differ. The loggerhead response parameters were...
Show moreSouth Florida's loggerhead (Caretta caretta), green (Chelonia mydas) and leatherback (Dermochelys coriacea) sea turtles hatchling have environmentally determined sex. The in situ nest mean hatchling sex ratios (SR) were highly female-biased : loggerhead F=0.89) and green turtle F=0.81; leatherback's SR was nearly balanced (0.55F). Nest temperatures and SRs differed between leatherbacks and loggerhead and green turtles. The latter two did not differ. The loggerhead response parameters were estimated within biological limitations by both 50-65% of incubation and mean middle 1/3 temperature. The maximum middle 1/3 temperature was the best-fit predictor for green turtles. No best-fit sex ratio-temperature response could be identified for leatherbacks. Clutches incubating under natural conditions can vary greatly in SR ; TRT differences may account for differences among species' sex ratios.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3361062
- Subject Headings
- Sex ratio, Sex determination, Genetic, Sea turtles, Nests, Sea turtles, Embryology, Loggerhead turtle, Nests, Loggerhead turtle, Effect of temperature on
- Format
- Document (PDF)
- Title
- Maternal and alloparental discipline in Atlantic spotted dolphins (Stenella frontalis) in the Bahamas.
- Creator
- Weinpress, Meghan., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Discipline was implemented by mothers and alloparent spotted dolphins (Stenella frontalis) mothers and alloparents on Little Bahama Bank, Bahamas. Disciplinarians were significantly more likely to be adults than juveniles. Although most disciplinarians were female, males were also observed to perform discipline. The recipients of discipline were male and female, and significantly more likely to be calves than juveniles. Pursuit, contact, and display behaviors were used in discipline, however...
Show moreDiscipline was implemented by mothers and alloparent spotted dolphins (Stenella frontalis) mothers and alloparents on Little Bahama Bank, Bahamas. Disciplinarians were significantly more likely to be adults than juveniles. Although most disciplinarians were female, males were also observed to perform discipline. The recipients of discipline were male and female, and significantly more likely to be calves than juveniles. Pursuit, contact, and display behaviors were used in discipline, however pursuit behaviors were most often observed. Variables such as age class, sex, and parity were not found to influence how discipline was implemented. The durations of all disciplinary pursuits were under thirty seconds, and successful pursuits had slightly shorter duration than unsuccessful pursuits. Disciplinarian success was not significantly influenced by age class, sex, parity, or behavior used.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3361254
- Subject Headings
- Animal behavior, Behavior evolution, Atlantic mammals, Behavior, Parent-child relationships, Social behavior in animals, Discipline of children, Atlantic spotted dolphin
- Format
- Document (PDF)
- Title
- Comparative ecophysiology of bloom-forming macroalgae in the Indian River Lagoon, Florida: Ulva lactuca (Chlorophyta), Hypnea musciformis, and Gracilaria tikvahiae (Rhodophyta).
- Creator
- Vlaming, Lisa N.A., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Macroalgal blooms are responses to nutrient enrichment in shallow seagrass ecosystems like the Indian River Lagoon (IRL), Florida. Little is known about nitrogen (N) and phosphorus (P) limitation or the importance of morphological/physiological characteristics of bloom-forming macroalgae (Ulva lactuca, Hypnea musciformis, and Gracilaria tikvahiae) in the IRL. We hypothesized: 1) all species would proliferate in nutrient-rich Titusville, 2) opportunistic U. lactuca would dominate, 3) Rapid...
Show moreMacroalgal blooms are responses to nutrient enrichment in shallow seagrass ecosystems like the Indian River Lagoon (IRL), Florida. Little is known about nitrogen (N) and phosphorus (P) limitation or the importance of morphological/physiological characteristics of bloom-forming macroalgae (Ulva lactuca, Hypnea musciformis, and Gracilaria tikvahiae) in the IRL. We hypothesized: 1) all species would proliferate in nutrient-rich Titusville, 2) opportunistic U. lactuca would dominate, 3) Rapid Light Curves (RLCs) would assess nutrient status, and 4) nutrient concentrations would regulate growth more than N:P ratios. Field studies showed rapid biomass doubling times of 2 days (U. lactuca; November 2012) in urbanized Titusville. RLCs in a guano-enriched island off Big Pine Key (BPK) and Titusville (Ulva spp.) were similar due to P-saturation. Laboratory studies showed three-fold higher RLCs and two-fold faster growth at high nutrient concentrations of N and P. Reductions of both N and P will be required to moderate future blooms.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3361257
- Subject Headings
- Marine algae, Marine algae, Ecophysiology, Marine algae, Adaptation, Algal blooms
- Format
- Document (PDF)
- Title
- The avian community characteristics of constructed treatment wetlands of South Florida.
- Creator
- Beck, Tyler J., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
This study compared the avian communities of treatment wetlands in South Florida called Stormwater Treatment Wetlands (STAs) to those in natural marshes and crop lands, and examined factors that influenced the size and structure of the avian communities within the STAs. The STAs contained a more abundant, rich and distinct avian community compared to reference land types. The STAs were dominated by wintering waterfowl, and therefore community patterns fluctuated more seasonally other land...
Show moreThis study compared the avian communities of treatment wetlands in South Florida called Stormwater Treatment Wetlands (STAs) to those in natural marshes and crop lands, and examined factors that influenced the size and structure of the avian communities within the STAs. The STAs contained a more abundant, rich and distinct avian community compared to reference land types. The STAs were dominated by wintering waterfowl, and therefore community patterns fluctuated more seasonally other land types. Within the STAs, density and richness in the fall and winter were much greater in the submerged aquatic vegetation than in the mixed emergent vegetation when waterfowl were present. The STAs maintain two vegetation treatments which enhanced their biodiversity value by supporting distinct avian communities with different migratory strategies This suggests the increase in treatment wetlands could partially offset the loss of natural wetlands, but avian communities in treatment wetlands are not surrogates for natural wetlands.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3362327
- Subject Headings
- Constructed wetlands, Wetland hydrology, Watershed management, Habitat (Ecology), Birds, Ecology
- Format
- Document (PDF)
- Title
- Diversity and selection in the major histocompatibility complex: DQA and immune function in IRL and Atlantic bottlenose dolphins (Tursiops truncatus).
- Creator
- Ferrer, Tatiana., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The Major Histocompatibility Complex (MHC) encodes proteins critical to the vertebrate immune response; therefore MHC diversity is an indicator of population health. I have (1) Isolated exon 2 of the class II gene DQA in Tursiops truncatus in the North Indian River Lagoon (IRL) (n=17), South IRL (n=29) and adjacent Atlantic waters (n=20), (2) assessed genetic variability between groups, (3) developed a method to genotype individuals, (4) typed 11 unique alleles in 66 individuals, (5) detected...
Show moreThe Major Histocompatibility Complex (MHC) encodes proteins critical to the vertebrate immune response; therefore MHC diversity is an indicator of population health. I have (1) Isolated exon 2 of the class II gene DQA in Tursiops truncatus in the North Indian River Lagoon (IRL) (n=17), South IRL (n=29) and adjacent Atlantic waters (n=20), (2) assessed genetic variability between groups, (3) developed a method to genotype individuals, (4) typed 11 unique alleles in 66 individuals, (5) detected geographic patterns of diversity between estuarine and coastal individuals (FST=0.1255, p<0.05), (6) found evidence of positive selection centered in the binding pockets P1, P6 and P9 of the peptide binding region (w=2.08), (7) found that patterns of polymorphism did not closely match patterns of diversity in neutral markers, (8) performed a pilot study with Orcinus orca. The initial findings highlight the need for further comparative work and suggest that silent mutations are not neutral.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3362335
- Subject Headings
- Major histocompatibility complex, Immunogenetics, Molecular genetics, Endocrine disrupting chemicals, Dolphins, Geographical distribution, Population genetics, Social behavior in animals
- Format
- Document (PDF)
- Title
- Visual and electrosensory ecology of batoid elasmobranchs.
- Creator
- Bedore, Christine N., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The electrosensory and visual adaptations of elasmobranchs to the environment have been more studied than most other senses, however, work on these senses is mostly limited to descriptive analyses of sensitivity, morphology, and behavior. The goal of this work was to explore electrosensory and visual capabilities in a more ecological context. To gain an understanding of the content of bioelectric signals, the magnitude and frequency of these stimuli were recorded from a broad survey of...
Show moreThe electrosensory and visual adaptations of elasmobranchs to the environment have been more studied than most other senses, however, work on these senses is mostly limited to descriptive analyses of sensitivity, morphology, and behavior. The goal of this work was to explore electrosensory and visual capabilities in a more ecological context. To gain an understanding of the content of bioelectric signals, the magnitude and frequency of these stimuli were recorded from a broad survey of elasmobranch prey items... Color vision adaptations also correlated to the photic environment of each species; cownose rays inhabit turbid, green-dominated waters and had two cone visual pigments that maximize contrast of objects against the green background... Yellow stingrays were trichromatic and likely possess the ability to discriminate colors in their clear, reef and seagrass habitats, which are spectrally rich. Both species showed evidence of ultraviolet sensitivity, which may aid in predator and conspecific detection as an enhanced communication channel. Future studies should investigate the integration of sensory input and sensory involvement in intraspecific communication to gain more insight into ecological adaptations.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3362337
- Subject Headings
- Visual discrimination, Adaptation (Biology), Animal ecophysiology, Chondrichthyes, Physiology
- Format
- Document (PDF)
- Title
- Electroreception in the obligate freshwater stingray, Potamotrygon motoro.
- Creator
- Harris, Lindsay L., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Elasmobranch fishes use electroreception to detect electric fields in the environment, particularly minute bioelectric fields produced by potential prey. A single elasmobranch family (Potamotrygonidae) is composed of obligate freshwater stingrays endemic to the Amazon River. A freshwater existence has imposed morphological adaptions on their electrosensory system due to life in a high impedance medium. Because their electrosensory morphology differs from their marine relatives, freshwater...
Show moreElasmobranch fishes use electroreception to detect electric fields in the environment, particularly minute bioelectric fields produced by potential prey. A single elasmobranch family (Potamotrygonidae) is composed of obligate freshwater stingrays endemic to the Amazon River. A freshwater existence has imposed morphological adaptions on their electrosensory system due to life in a high impedance medium. Because their electrosensory morphology differs from their marine relatives, freshwater stingrays may demonstrate corresponding differences in behavioral sensitivity. The objective of this study was to quantify behavioral sensitivity of the obligate freshwater stingray Potamotrygon motoro to prey-simulating voltage. The voltage produced by common teleost prey of P. motoro were measured and replicated for behavioral trials. The best response was 10.62 cm, and the smallest voltage gradient detected was 0.005 mVcm-1. This sensitivity is reduced compared to marine species. The conductivity of the medium, more so than ampullary morphology, may dictate sensitivity of the elasmobranch electrosensory system.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3362382
- Subject Headings
- Fishes, Sense organs, FIshes, Physiology, Stingrays, Physiology, Fish culture
- Format
- Document (PDF)
- Title
- Hippocampal neurogenesis in the SERT ALA56 mouse model to autism.
- Creator
- Di Mase, Julieta Maria, Guthrie, Kathleen, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The causes of autism spectrum disorder (ASD) are not all known, but it is suspected that the serotonin transporter (SERT) plays an important role for some subjects with ASD. Mutations in the SLC6A4 gene, that encodes SERT, including the Ala56 mutation (Gly56Ala), have been found in some autism patients. This mutation makes the transporter more active and reduces the probability of serotonergic neurotransmission in the brain, which is linked to behavioral changes that are associated with core...
Show moreThe causes of autism spectrum disorder (ASD) are not all known, but it is suspected that the serotonin transporter (SERT) plays an important role for some subjects with ASD. Mutations in the SLC6A4 gene, that encodes SERT, including the Ala56 mutation (Gly56Ala), have been found in some autism patients. This mutation makes the transporter more active and reduces the probability of serotonergic neurotransmission in the brain, which is linked to behavioral changes that are associated with core domain deficits of ASD 1. Depression also has been linked to decreases in the availability of serotonin (5-hydroxytryptamine; 5-HT) in the central nervous system (CNS), and is associated with reduced hippocampal neurogenesis. Selective serotonin reuptake inhibitors (SSRIs), drugs used to block SERTs, are used to treat depression and/or anxiety by inhibiting SERT to increase synaptic 5-HT levels.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013297
- Subject Headings
- Autism Spectrum Disorder, Hippocampus, Neurogenesis, Serotonin Plasma Membrane Transport Proteins
- Format
- Document (PDF)
- Title
- POPULATION GENETICS AND ALGAL SYMBIONT COMMUNITIES OF THE CORAL SPECIES MONTASTRAEA CAVERNOSA ON THE BELIZE BARRIER REEF.
- Creator
- Eckert, Ryan J., Voss, Joshua D., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Coral reefs worldwide are experiencing unprecedented and rapid declines. However, deeper, mesophotic coral ecosystems (MCEs; 30–150 m) may act as refuges for coral species, providing larvae to recolonize degraded shallow reefs. This study assessed the genetic connectivity of shallow and mesophotic Montastraea cavernosa populations on the Belize Barrier Reef and the community structure of their endosymbiotic algae (Family Symbiodiniaceae) across a fine-scale depth gradient (10, 16, 25, 35 m)....
Show moreCoral reefs worldwide are experiencing unprecedented and rapid declines. However, deeper, mesophotic coral ecosystems (MCEs; 30–150 m) may act as refuges for coral species, providing larvae to recolonize degraded shallow reefs. This study assessed the genetic connectivity of shallow and mesophotic Montastraea cavernosa populations on the Belize Barrier Reef and the community structure of their endosymbiotic algae (Family Symbiodiniaceae) across a fine-scale depth gradient (10, 16, 25, 35 m). Evaluation of nine polymorphic microsatellite markers demonstrated that relatively shallow (10 and 16 m) M. cavernosa populations were genetically distinct from relatively deep (25 and 35 m) populations. High throughput sequencing of ribosomal coding DNA from Symbiodiniaceae communities of M. cavernosa revealed differences in community structure across depth, with shallow-specialist and depth-generalist community profiles. This research provides important information for the management of distinct deep and adds to the body of research on the understudied MCEs of the Mesoamerican Reef.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013302
- Subject Headings
- Montastraea, Coral reefs and islands--Belize, Mesoamerican Reef, Population genetics, Symbiosis
- Format
- Document (PDF)
- Title
- ADVANCING THE CULTIVABILITY OF SOIL BACTERIA USING A DYNAMIC SOIL ENVIRONMENT AND SOIL EXTRACT METHOD.
- Creator
- España, Erick, Brooks, Randy W., Esiobu, Nwadiuto, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Bacteria are inarguably the most ubiquitous and adaptive organisms on the planet. The vast, diverse community of microbes residing in soil are mostly studied using sequencing technologies because over 99% of them are currently uncultivable in the laboratory. This lack of diverse bacterial cultivation presents a serious challenge for modern microbiological and medical science where the discovery of novel antibiotic producers and microbial products has been outpaced by the rise in drug...
Show moreBacteria are inarguably the most ubiquitous and adaptive organisms on the planet. The vast, diverse community of microbes residing in soil are mostly studied using sequencing technologies because over 99% of them are currently uncultivable in the laboratory. This lack of diverse bacterial cultivation presents a serious challenge for modern microbiological and medical science where the discovery of novel antibiotic producers and microbial products has been outpaced by the rise in drug resistance. This study designed and tested two new cost-effective culture systems called the “Dynamic Soil Environment” and Soil Extract Systems with the goal of increasing the cultivable communities of diverse bacteria in a soil sample over standard methods. Illumina MiSeq sequencing and DADA2 pipeline protocols were used to analyze community DNA from cultivated samples and source soil metagenomes. Autoclaved soil extract media in the Soil Extract Experiment yielded a statistically significantly greater Shannon’s (p = 0.008) and Simpson’s diversity (p = 0.007) of bacteria over pH modified (6.4) nutrient agar media over 30 days of incubation. Autoclaved soil extract media was also able to cultivate, on average, 33% of species in bulk soil sequences compared to 27% from standard nutrient agar however these differences weren’t statistically significant. The length of incubation had a lesser effect than media type on yield of bacteria over 30 days in batch culture conditions. Species richness and diversity generally decreased over time except in soil extract samples. In the Dynamic Soil Environment experiment, membrane plates placed on a live soil environment produced a slightly higher diversity than autoclaved membrane plates and control plates without soil, however, these differences were not statistically significant except when analyzed with Chao1 diversity (0.041). Cultivated bacterial diversity and communities differed more according to media type than soil environment with statistically significant differences between standard and pH modified nutrient agar. Media with a 5.8 pH buffer produced a significantly higher relative abundance of the well-known antibiotic-producers, Actinobacteria (t(10) = -5.715, p < .000) and also Proteobacteria (t(10) = -10.127, p < .000). This study establishes cost-effective methods of cultivating more diverse bacterial communities for low-funded laboratories. Culture conditions for the reliable cultivation of higher relative abundances of bacterial groups belonging to Actinobacteria and Proteobacteria are also established with the Dynamic Soil Environment Experiment.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013304
- Subject Headings
- Bacteriological Techniques--methods, Bacteriology--Cultures and culture media, Soil
- Format
- Document (PDF)
- Title
- THE USE OF CHEMICAL CUES BY SARGASSUM SHRIMPS LEANDER TENUICORNIS AND LATREUTES FUCORUM IN ESTABLISHING AND MAINTAINING A SYMBIOSIS WITH SARGASSUM ALGAE.
- Creator
- Frahm, Jaime L., Brooks, Randy, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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A mutualistic symbiosis exists between the alga Sargassum spp. and two shrimp species, L. tenuicornis and L. fucorum. But little is known about how the shrimp locate their host alga. Both visual and chemical cues are potentially available. Visual cues would be presumably restricted at night but chemical cues are potentially available continuously. Additionally, a previous study has looked at both cue variables with results that are mixed. This current research elaborates on the previous study...
Show moreA mutualistic symbiosis exists between the alga Sargassum spp. and two shrimp species, L. tenuicornis and L. fucorum. But little is known about how the shrimp locate their host alga. Both visual and chemical cues are potentially available. Visual cues would be presumably restricted at night but chemical cues are potentially available continuously. Additionally, a previous study has looked at both cue variables with results that are mixed. This current research elaborates on the previous study in an attempt to fully understand Sargassum shrimp chemoreception. A y-maze and four-chambered apparatus were used to test if the shrimp were able to detect Sargassum cues, conspecific cues, and Dimethylsulfoniopropionate (DMSP) cues. Neither shrimp species showed a strong directional response to any of the chemical cues, but the Sargassum and DMSP cues did cause more shrimp to exhibit searching behavior. Additionally, several differences in response between male and female shrimp were found for each cue. A weaker dilution of DMSP was tested in an attempt to determine sensitivity of L. fucorum shrimp to the chemical cue. This weaker dilution also caused L. fucorum to exhibit searching behavior, but the sensitivity to the cue was not found and further research is needed to fully answer this question. These results show the shrimp are able to detect chemical cues in their environment and help determine more accurately the role of chemoreception in initiating and maintaining this shrimp/algal association.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013308
- Subject Headings
- Sargassum, Symbiosis, Shrimps, Leander (Crustacea), Hippolytidae
- Format
- Document (PDF)
- Title
- HISTAMINERGIC AND NOCICEPTIVE GROOMING IN DROSOPHILA MELANOGASTER: AN ANALYSIS OF THE MOLECULAR MECHANISMS AND A BEHAVIORAL RESPONSE TO NOXIOUS CHEMICAL STIMULI.
- Creator
- John, Ciny, Dawson-Scully, Ken, Murphey, Rodney, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Insect grooming has various functions, including defense against parasites and pathogens, cleaning of dust particles, and maintenance of sensory receptors. The hierarchy of grooming behavior suggests that cleaning one body part is more crucial than the other, the priority order more specifically being eyes, antennae, abdomen, then wings, followed by the thorax. Histamine is an extensively studied neurotransmitter found in the central nervous system of many animals. In Drosophila, histamine is...
Show moreInsect grooming has various functions, including defense against parasites and pathogens, cleaning of dust particles, and maintenance of sensory receptors. The hierarchy of grooming behavior suggests that cleaning one body part is more crucial than the other, the priority order more specifically being eyes, antennae, abdomen, then wings, followed by the thorax. Histamine is an extensively studied neurotransmitter found in the central nervous system of many animals. In Drosophila, histamine is found in both the peripheral and central nervous systems and is necessary for visual and mechanosensory behaviors. Histamine-gated chloride channel 1 (HisCl1) and Ora transientless (Ort) are two characterized histamine receptors, both of which are vital for visual signaling in the fly.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013321
- Subject Headings
- Drosophila melanogaster, Grooming behavior in animals, Nociception, Histaminergic mechanisms
- Format
- Document (PDF)
- Title
- A Framework for Understanding Power Supply and Demand in Presynaptic Nerve Terminals.
- Creator
- Justs, Karlis Anthony, Macleod, Gregory T., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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The molecular mechanisms of synaptic function and development have been studied extensively, but little is known about the energy requirements of synapses, or the mechanisms that coordinate their energy production with their metabolic demands. These are oversights, as synapses with high energy demands are more susceptible to degeneration and degrade in the early stages of diseases such as amyotrophic lateral sclerosis, spinal muscle atrophy and Parkinson’s disease. Here, in a structure...
Show moreThe molecular mechanisms of synaptic function and development have been studied extensively, but little is known about the energy requirements of synapses, or the mechanisms that coordinate their energy production with their metabolic demands. These are oversights, as synapses with high energy demands are more susceptible to degeneration and degrade in the early stages of diseases such as amyotrophic lateral sclerosis, spinal muscle atrophy and Parkinson’s disease. Here, in a structure-function study at Drosophila motor neuron terminals, a neurophysiological model was generated to investigate how power (ATP/s) supply is integrated to satisfy the power demand of presynaptic terminals. Power demands were estimated from six nerve terminals through direct measurements of neurotransmitter release and Ca2+ entry, as well as theoretical estimation of Na+ entry and power demands at rest (cost of housekeeping). The data was leveraged with a computational model that simulated the power demands of the terminals during their physiological activity, revealing high volatility in which power demands can increase 15-fold within milliseconds as neurons transition from rest to activity. Another computational model was generated that simulated ATP production scenarios regarding feedback to the power supply machinery (Oxphos and glycolysis) through changes in nucleotide concentrations, showing that feedback from nucleotides alone fail to stimulate power supply to match the power demands of each terminal. Failure of feedback models invokes the need for feed forward mechanisms (such as Ca2+) to stimulate power supply machinery to match power demands. We also quantified mitochondrial volume, density, number and size in each nerve terminal, revealing all four features positively correlate with the terminals power demands. This suggests the terminals enhance their oxidative capacity by increasing mitochondrial content to satisfy their power demands. And lastly, we demonstrate that abolishing an ATP buffering system (the phosphagen system) does not impair neurotransmission in the nerve terminals, suggesting motor nerve terminals are capable of satisfying their power demands without the ATP buffering system.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013323
- Subject Headings
- Presynaptic Terminals, Adenosine triphosphate, Synapses--metabolism, Bioenergetics
- Format
- Document (PDF)
- Title
- MULTISCALE FUNCTIONAL ARCHITECTURE OF NEOCORTEX: FROM CLUSTERS TO COLUMNS.
- Creator
- Lee, Kuo-Sheng, Fitzpatrick, David, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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The physical architecture of neural circuits is thought to underlie the computations that give rise to higher order feature sensitivity in the neocortex. Recent technological breakthroughs have allowed the structural and functional investigation of the basic computational units of neural circuits; individual synaptic connections. However, it remains unclear how cortical neurons sample and integrate the thousands of synaptic inputs, supplied by different brain structures, to achieve feature...
Show moreThe physical architecture of neural circuits is thought to underlie the computations that give rise to higher order feature sensitivity in the neocortex. Recent technological breakthroughs have allowed the structural and functional investigation of the basic computational units of neural circuits; individual synaptic connections. However, it remains unclear how cortical neurons sample and integrate the thousands of synaptic inputs, supplied by different brain structures, to achieve feature selectivity. Here, I first describe how visual cortical circuits transform the elementary inputs supplied by the periphery into highly diverse, but well-organized, feature representations. By combining and optimizing newly developed techniques to map the functional synaptic connections with defined sources of inputs, I show that the intersection between columnar architecture and dendritic sampling strategies can lead to the selectivity properties of individual neurons: First, in the canonical feedforward circuit, the basal dendrites of a pyramidal neuron utilize unique strategies to sample ON (light increment) and OFF (light decrement) inputs in orientation columns to create the distinctive receptive field structure that is responsible for basic sensitivity to visual spatial location, orientation, spatial frequency, and phase. Second, for long-range horizontal connections, apical dendrites unbiasedly integrate functionally specialized and spatially targeted inputs in different orientation columns, which generates specific axial surround modulation of the receptive field.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013327
- Subject Headings
- Neocortex, Visual Cortex--physiology, Neural circuitry, Dendrites
- Format
- Document (PDF)
- Title
- Thermodynamic profiles of the interactions of suramin, chondroitin sulfate, and pentosan polysulfate with the inhibitory domain of tissue inhibitor of metalloproteinases 3.
- Creator
- Logue, Timothy, Brew, Keith, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Tissue inhibitor of metalloproteinase-3 (TIMP-3) is a protein with multiple functions that include regulating the turnover of the extracellular matrix (ECM) by inhibiting members of the metzincin family. Extracellular levels of soluble TIMP-3 are low, reflecting its binding to components of the ECM including sulfated glycosaminoglycans (SGAGs) and its endocytosis by low density lipoprotein receptor-related protein 1. Because TIMP-3 inhibits ECM-degrading enzymes, the ability of SGAG mimetics...
Show moreTissue inhibitor of metalloproteinase-3 (TIMP-3) is a protein with multiple functions that include regulating the turnover of the extracellular matrix (ECM) by inhibiting members of the metzincin family. Extracellular levels of soluble TIMP-3 are low, reflecting its binding to components of the ECM including sulfated glycosaminoglycans (SGAGs) and its endocytosis by low density lipoprotein receptor-related protein 1. Because TIMP-3 inhibits ECM-degrading enzymes, the ability of SGAG mimetics to elevate extracellular concentrations of TIMP3 is of interest for osteoarthritis treatment. However, previous studies of such interactions have utilized immobilized forms of the protein or ligands. Here we have quantified the thermodynamics of the interactions of the inhibitory domain of TIMP-3 with chondroitin sulfate (CS), pentosan polysulfate (PPS) and suramin in solution using isothermal titration calorimetry. All three interactions are driven by a (favorable) negative enthalpy ychange combined with an unfavorable decrease in entropy. The heat capacity change (ΔCp) for the interaction of N-TIMP-3 with CS, PPS, or suramin is essentially zero, indicating an insignificant contribution from the hydrophobic effect. Based on the effects of ionic strength on the interaction of N-TIMP-3 with suramin, their interaction appears to be driven by electrostatic interactions. Modeling supports the view that the negatively charged sulfates of CS, PPS, and suramin interact with a cationic region on N-TIMP-3 that includes Lys -26, -27, -30, and -possibly 76 on the opposite face of TIMP-3 from its reactive site for metalloproteases.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013328
- Subject Headings
- Tissue Inhibitor of Metalloproteinases, Osteoarthritis--Treatment, Suramin, Chondroitin Sulfates, Pentosans
- Format
- Document (PDF)
