Marine Biology Commons^™

The Impacts Of Embryonic Arsenic Exposure Of Fundulus Heteroclitus, Torey Bowser

Electronic Theses and Dissertations

Arsenic is a toxic metalloid that exceeds safe drinking water standards in groundwater in many locations worldwide. Arsenic exposure in fish has been linked to destruction of gill tissues, impairment of growth, decreased muscle mass, memory impairment, increased aggression, and avoidance behaviors. We examined the behavior of mummichogs (Fundulus heteroclitus) following arsenic exposure during development in two studies. Embryos were collected from fish from three reference sites: Scorton Creek (SC), Massachusetts, Wells Harbor (WE), Maine, and Block Island (BLOC), Rhode Island and two contaminated sites: Callahan Mine (CM), Brooksville, Maine, and New Bedford Harbor (NBH), Massachusetts. Embryos were …

Characterization Of The Whale Shark (Rhincodon Typus) Melanocortin-2 Receptor, Brianne Hoglin

Electronic Theses and Dissertations

Among bony vertebrates, the melanocortin-2 receptor ortholog is unique among the family of five melanocortin receptors on the basis that it is dependent on its accessory protein, MRAP1, for trafficking and activation, and is selective for activation by ACTH alone. Previous studies on the MC2R orthologs of select cartilaginous fish, the elephant shark (Callorhinchus milii) and the red stingray (Dasyatis akajei), revealed divergent traits in a less obligatory relationship on MRAP1 and its ability to be activated by ACTH or the MSH-sized peptides. However, observed traits were not consistent between these two cartilaginous fish species, posing …

Transgenerational Plasticity Causes Differences In Uv-Tolerance Of Intertidal And Subtidal Populations Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, Yareli Alvarez, Nikki L. Adams

Master's Theses

Planktonic larvae of marine organisms are increasingly being exposed and required to respond to a changing physical environment. Adult sea urchins occupy both intertidal and subtidal waters and broadcast spawn gametes into the water column to contend with variable physical conditions. To answer how populations of invertebrates residing at different depths adequately prepare their offspring to cope with different levels of ultraviolet radiation (UVR), we collected adult purple sea urchins, Strongylocentrotus purpuratus, from four sites (two intertidal and two subtidal (~15 m deep)) on the central coast of CA to compare UV tolerance in offspring. Our measurements of UVA …

Multi-Generational Effects Of ∆9-Tetrahydrocannabinol Exposure On Gene Expression In Liver Tissue, Kayla Lovitt

Honors Theses

Cannabis is the most commonly used, cultivated, and trafficked illicit drug worldwide. Increased availability and acceptance of cannabis and cannabinoid-containing products provide the necessity for understanding how these substances influence aging. In this study, zebrafish (Danio rerio) were exposed to concentrations of Δ⁹-tetrahydrocannabinol (THC) (0.08, 0.4, 2 µM) during embryonic-larval development, the effects on aging were measured 30 months later and in the offspring of the exposed fish (F1 generation. We observed results indicating a biphasic and hormetic effect. Treatment with the lowest concentration of THC significantly increased egg production, while higher concentrations resulted in impaired …

Non-Invasive Method For Leptin Supplementation In Zebrafish (Danio Rerio), Regan Mcnamara

Williams Honors College, Honors Research Projects

I tested the hypothesis that recombinant leptin protein can be introduced to zebrafish in vivo through non-invasive soaking in a solution containing the protein. One way to study various molecules’ effects in vivo is through intraperitoneal or intracerebroventricular injections during the embryonic or larval stage, which is invasive, difficult to administer, and can have a high mortality rate. 48 hours post fertilization (hpf) zebrafish were soaked in a His-tagged recombinant leptin protein solution at 10 nM and 100 nM concentrations (produced by Genscript). After soaking, zebrafish larvae were washed extensively to remove all recombinant protein on their exterior before homogenization. …

Development And Validation Of Gene Delivery Methods For ​Crassostrea Virginica, Adrienne N. Tracy

Honors Theses

The Eastern oyster (Crassostrea virginica) is an important part of the East Coastal USA economy because aquaculture creates jobs. Sadly, the oysters are under constant threat due to increasing pollution, red tides, and diseases. Bivalves, and oysters in particular, are also becoming potential model organisms in medical research. With the sequencing of the oyster genome, scientists are focusing on deciphering the function of the predicted genes. However, the limited number of molecular and cellular tools available makes functional annotation of the genome challenging. A consistent, replicable gene delivery system needs to be developed to assess gene function and understand the …

Effect Of Oxygen-Limiting Tidal Conditions On Muscle Metabolism And Structure In The Giant Acorn Barnacle, Balanus Nubilus, Katie O. Grady

Master's Theses

Crustacean muscle fibers are some of the largest cells in the animal kingdom, with fiber diameters in the giant acorn barnacle (Balanus nubilus) exceeding 3 mm. Sessile animals with extreme muscle sizes and that live in the hypoxia-inducing intertidal zone – like B. nubilus – represent ideal models for probing the effects of oxygen limitation on muscle cells. We investigated changes in metabolism and structure of B. nubilus muscle in response to: normoxic immersion, anoxic immersion, or air emersion, for acute (6h) or chronic (6h exposures twice daily for 2wks) time periods. Following exposure, we immediately measured hemolymph …

Insulin-Like Growth Factor Pathway Described In Austrofundulus Limnaeus Diapause And Escape Embryos, Steven Cody Woll

Dissertations and Theses

Development in the annual killifish Austrofundulus limnaeus can follow two distinct developmental trajectories. Typical development includes the entrance of embryos into a state of metabolic and developmental arrest termed diapause. Alternately, embryos can escape diapause and develop directly without pause. These two trajectories are characterized by differences in the rate and timing of developmental, morphological, and physiological traits. Insulin and Insulin-like growth factor (IGF) signaling (IIS) is known to regulate entrance into diapause in a variety of invertebrates. In this thesis I explore the possible role of IGFs in the regulation of development and diapause in embryos of A. limnaeus …

Evolvability Of The Skull: A Study Of Genetic Basis And Integration In The Teleost Craniofacial Skeleton, Yinan Hu

Doctoral Dissertations

As the field of evolutionary biology pivots away from a gene-centric view of how adaptive evolution proceeds, renewed emphasis is placed on the origin of phenotypic variation. Understanding the developmental processes that underlie the production of novel traits, and how they might influence evolvability, is considered a primary goal in the on-going “extended evolutionary synthesis”. The following dissertation explores these questions in the context of adaptive radiations in fish, with a focus on morphological variation in the craniofacial skeleton. Specifically, the first chapter investigates the genetic and developmental basis of shape (co-)variation in the feeding apparatus of African cichlid fishes, …

The Effects Of Triiodothyronine, Glucose, Alanine, And Iodide As Nutrients On The Survival And Successful Metamorphosis Of Aeolidiella Stephanieae Veligers, Bryan Tate

All Theses And Dissertations

During early life stages, nutrients are crucial to the proper development of larval marine invertebrates. Many such larvae are lecithotrophic and therefore do not actively feed; however, a large body of research has shown that lecithotrophic larvae take in dissolved organic material (DOM) including amino acids and sugars, contributing heavily to metabolic requirements. Another dissolved nutrient, iodine, is useful to marine invertebrates for the production of organic compounds. Some of these compounds (thyroid hormones, THs) are historically thought to be used almost exclusively by vertebrates, though studies have shown that THs are also useful to some marine invertebrates for developmental …

Morphological And Molecular Defects In Zebrafish Embryos (Danio Rerio) After Chromated Copper Arsenate Exposure, Kerry Jean Lee

Biological Sciences Theses & Dissertations

This investigation identified the morphological defects caused by different concentrations of chromium, copper, and arsenic (CCA) on the developing zebrafish embryo; in addition to defects caused by the three combined components (complete CCA). A change in the DNA of the developing embryos in response to the three components of CCA and complete CCA was also determined. Early Dania rerio embryos were cultured for five days with various concentrations of CCA components and complete CCA. Morphological defects were assessed with light microscopy and DNA fragmentation was determined by agarose gel electrophoresis. Embryonic exposure of D. rerio to sub lethal concentrations of …

The Growth And Bioenergetics Of Callinectes Sapidus Larvae And The Effects Of Diet Quality On Larval Physiology, James J. Pletl

OES Theses and Dissertations

Food quality, especially ω3 polyunsaturated fatty acids (PUFA), can affect the physiology and metabolic efficiency of larvae of the blue crab, Callinectes sapidus. These affects may correlate with success in development and juvenile recruitment.

Larvae were exposed to two diets differing quantitatively in ω3 PUFA and respiration, excretion, growth, and feeding rates were measured for each larval stage and the megalopal stage. The energy partitioned to molts and specific dynamic action was also measured. T

he ω3 PUFA enriched diet resulted in a lower respiration rate when compared to the unsupplemented diet, but there was little differences in excretion …