Biology Commons^™

Iucn Conservation Status Does Not Predict Glucocortoid Concentrations In Reptiles And Birds, L. B. Martin, Maren N. Vitousek, Jeremy W. Donald, T. Flock, M. J. Fuxjager, W. Goymann, M. Hau, Jerry F. Husak, Michele A. Johnson, Bonnie K. Kircher, R. Knapp, E. T. Miller, L. A. Schoenle, T. D. Williams, C. D. Francis

Biology Faculty Research

Circulating glucocorticoids (GCs) are the most commonly used biomarkers of stress in wildlife. However, their utility as a tool for identifying and/or managing at-risk species has varied. Here, we took a very broad approach to conservation physiology, asking whether International Union for the Conservation of Nature (IUCN) listing status (concern versus no obvious concern) and/or location within a geographic range (edge versus non-edge) predicted baseline and post-restraint concentrations of corticosterone (CORT) among many species of birds and reptiles. Even though such an approach can be viewed as coarse, we asked in this analysis whether CORT concentrations might be useful to …

Untangling The Effects Of Biosynthetic And Metabolic Rates On Oxidative Cellular Damage In An Insect Model, Nikki Jihui Gomez

Masters Theses

“Previously, a theoretical model for unravelling the entwined effects of metabolic and biosynthetic rates on oxidative cellular damage accumulation during an animal’s growth period was developed and tested in hornworms (Manduca sexta larvae). In theory, if an animal had unrestricted amounts of energy and a high repair efficiency, they could repair most of the oxidative cellular damage accumulated, regardless of how their metabolic rate varies. However, organisms have a finite amount of energy that is allocated to repair and, during the animal’s development period, a considerable amount of energy goes towards growth eliciting a tradeoff between biosynthesis and repair. …

The Toxicity Of Nanoparticles Depends On Multiple Molecular And Physicochemical Mechanisms, Yue-Wern Huang, Melissa Cambre, Han-Jung Lee

Biological Sciences Faculty Research & Creative Works

Nanotechnology is an emerging discipline that studies matters at the nanoscale level. Eventually, the goal is to manipulate matters at the atomic level to serve mankind. One growing area in nanotechnology is biomedical applications, which involve disease management and the discovery of basic biological principles. In this review, we discuss characteristics of nanomaterials, with an emphasis on transition metal oxide nanoparticles that influence cytotoxicity. Identification of those properties may lead to the design of more efficient and safer nanosized products for various industrial purposes and provide guidance for assessment of human and environmental health risk. We then investigate biochemical and …

Delayed Effects Of Sub-Lethal Lampricide, 3-Trifluoromethyl-4-Nitrophenol (Tfm), Exposure On The Metabolic Physiology Of Juvenile Lake Sturgeon (Acipenser Fulvescens), Matthew J. Symbal

All NMU Master's Theses

The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) can be lethal to juvenile lake sturgeon (Acipenser fulvescens) at high concentrations used to control invasive sea lamprey (Petromyzon marinus). Little is known about how TFM would affect juvenile lake sturgeon (age-0) at the sub-lethal concentrations encountered during routine lampricide treatments; specifically, its effects on growth, stress response, and metabolism. Age-0 lake sturgeon were exposed to TFM concentrations at levels 0.0x, 0.5x, and 1.0x the minimum lethal concentration (mlc) of TFM required to kill 99.9% of sea lamprey larvae during a routine stream treatment. The mlc was estimated based on pH and alkalinity …

Regulation Of Mtorc1 By Homocysteine And Its Effects On Autophagy In Human And Mouse Neuronal Tissues, Khoosheh Khayati

Dissertations

The molecular mechanisms leading to and responsible for age-related, sporadic Alzheimer’s disease (AD) remain largely unknown. It is well documented that aging patients with elevated levels of the amino acid metabolite homocysteine (Hcy) are at high risk of developing AD. The impact of Hcy on molecular clearance pathways in mammalian cells, including in-vitro cultured induced pluripotent stem cell-derived forebrain neurons and in-vivo neurons in mouse brains is investigated in this research project. Exposure to high Hcy levels results in up-regulation of the mechanistic target of rapamycin complex 1 (mTORC1) activity, one of the major kinases in cells that is tightly …

Blue-Light Induced Accumulation Of Reactive Oxygen Species Is A Consequence Of The Drosophila Cryptochrome Photocycle, Louis David Arthaut, Margaret Ahmad, Nathalie Jourdan, Ali Mteyrek, Maria Procopio, Mohamed A. El-Esawi, Alain D'Harlingue, Pierre Etienne Bouchet, Jacques Witczak, Carlos F. Martino

Biomedical Engineering and Sciences Faculty Publications

Cryptochromes are evolutionarily conserved blue-light absorbing flavoproteins which participate in many important cellular processes including in entrainment of the circadian clock in plants, Drosophila and humans. Drosophila melanogaster cryptochrome (DmCry) absorbs light through a flavin (FAD) cofactor that undergoes photoreduction to the anionic radical (FAD) redox state both in vitro and in vivo. However, recent efforts to link this photoconversion to the initiation of a biological response have remained controversial. Here, we show by kinetic modeling of the DmCry photocycle that the fluence dependence, quantum yield, and half-life of flavin redox state interconversion are consistent with the anionic radical (FAD∗-) …

Age And Sex-Specific Effect Of Caloric Restriction On Circadian Clock And Longevity-Associated Gene Expression, Arten Andreyevich Astafev

ETD Archive

The rhythms in the expression of circadian clock genes are affected by calorie restriction (CR), a dietary paradigm known to increase lifespan. In our current study, we show that circadian rhythms are influenced by sex and the effects of CR are different between males and females. In particular, we found a group of clock genes which showed a sex-dependent difference in expression, as well as in response to CR (Rev-Erb α, Ror γ and both Cryptochromes: Cry1 and Cry2 genes). Two clock genes showed no difference in expression but their response to CR showed sexual dimorphism (Ror α and Rev-Erb …

The Effect Of Nullomer-Derived Peptides 9r, 9s1r And 124r On The Nci-60 Panel And Normal Cell Lines, Abdelkrim Alileche, Greg Hampikian

Biology Faculty Publications and Presentations

Background: Nullomer peptides are the smallest sequences absent from databases of natural proteins. We first began compiling a list of absent 5-amino acid strings in 2006 (1). We report here the effects of Nullomer-derived peptides 9R, 9S1R and 124R on the NCI-60 panel, derived from human cancers of 9 organs (kidney, ovary, skin melanoma, lung, brain, lung, colon, prostate and the hematopoietic system), and four normal cell lines (endothelial HUVEC, skin fibroblasts BJ, colon epithelial FHC and normal prostate RWPE-1).

Methods: NCI-60 cancer cell panel and four normal cell lines were cultured in vitro in RPMI1640 supplemented with 10% Hyclone …

Discovery And Characterization Of A Novel Class Of Metabolic Regulators In The Malaria Parasite Plasmodium Falciparum, Ann Marie Guggisberg

Arts & Sciences Graduate Student Theses and Dissertations

The malaria parasite, Plasmodium falciparum, infects hundreds of millions of people per year and causes hundreds of thousands of deaths. Within the host red blood cell, the parasite relies on glycolysis for energy and synthesis of essential biomolecules. One such anabolic fate of glucose is the synthesis of isoprenoids, a broad and essential class of compounds that participate in a variety of cellular functions. In the face of ever-evolving drug resistance, new inhibitors and better understanding of parasite metabolism are required. The antibiotic fosmidomycin (FSM) targets the methylerythritol phosphate pathway for isoprenoid synthesis and is a well-validated inhibitor of P. …

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 …

Pyruvate Oxidase Of Streptococcus Pneumoniae Contributes To Penumolysin Release, Joseph C. Bryant, Ridge C. Dabbs, Katie L. Oswalt, Lindsey R. Brown, Jason W. Rosch, Keun S. Seo, Janet R. Donaldson, Larry S. Mcdaniel, Justin A. Thornton

Faculty Publications

Background

Streptococcus pneumoniae is one of the leading causes of community acquired pneumonia and acute otitis media. Certain aspects of S. pneumoniae’s virulence are dependent upon expression and release of the protein toxin pneumolysin (PLY) and upon the activity of the peroxide-producing enzyme, pyruvate oxidase (SpxB). We investigated the possible synergy of these two proteins and identified that release of PLY is enhanced by expression of SpxB prior to stationary phase growth.

Results

Mutants lacking the <>spxB gene were defective in PLY release and complementation of spxB restored PLY release. This was demonstrated by cytotoxic effects of sterile filtered …

Exercise To The Rescue: An Analysis Of Altered Metabolic Gene Regulation Post-Exercise In Lean And Obese Individuals, Brandon Mudd

Mahurin Honors College Capstone Experience/Thesis Projects

The skeletal muscle of obese individuals exhibits a depressed ability to metabolize fats. Exercise training is thought to rescue this dampened ability to metabolize fats; mediated by a coordinated increase in the expression of a network of genes that regulate metabolism and fuel utilization. The purpose of this study is to determine the exercise-induced regulation of metabolically important genes in lean and obese individuals. Muscle biopsies (one pre-exercise/baseline and one immediately post-exercise) were obtained from 4 lean (BF% 24.4 ± 5.5; 23.5 yrs ± 1.9) and 13 obese (BF% 39.7 ± 2.4; 26.1 yrs ± 2.3), age-matched, relatively young subjects, …

Identification Of A Short Cell-Penetrating Peptide From Bovine Lactoferricin For Intracellular Delivery Of Dna In Human A549 Cells, Betty Revon Liu, Yue-Wern Huang, Robert Aronstam, Han-Jung Lee

Biological Sciences Faculty Research & Creative Works

Cell-penetrating peptides (CPPs) have been shown to deliver cargos, including protein, DNA, RNA, and nanomaterials, in fully active forms into live cells. Most of the CPP sequences in use today are based on non-native proteins that may be immunogenic. Here we demonstrate that the L5a CPP (RRWQW) from bovine lactoferricin (LFcin), stably and noncovalently complexed with plasmid DNA and prepared at an optimal nitrogen/phosphate ratio of 12, is able to efficiently enter into human lung cancer A549 cells. The L5a CPP delivered a plasmid containing the enhanced green fluorescent protein (EGFP) coding sequence that was subsequently expressed in …

Normal Glycolytic Enzyme Activity Is Critical For Hypoxia Inducible Factor-1a Activity And Provides Novel Targets For Inhibiting Tumor Growth, Geoffrey Grandjean Phd

Dissertations and Theses (Open Access)

Normal Glycolytic Enzyme Activity is Critical for Hypoxia Inducible Factor-1α Activity and Provides Novel Targets for Inhibiting Tumor Growth

By Geoffrey Grandjean

Advisory Professor: Garth Powis, D. Phil

Unique to proliferating cancer cells is the observation that their increased need for energy is provided by a high rate of glycolysis followed by lactic acid fermentation in a process known as the Warburg Effect, a process many times less efficient than oxidative phosphorylation employed by normal cells to satisfy a similar energy demand ^[1]. This high rate of glycolysis occurs regardless of the concentration of oxygen in the cell and …

Impact Of Sleep And Circadian Disruption On Energy Balance And Diabetes: A Summary Of Workshop Discussions, Deanna M. Arble, Joseph Bass, Cecilia Diniz Behn, Matthew P. Butler, Etienne Challet, Charles Czeisler, Christopher M. Depner, Joel Elmquist, Paul Franken, Michael A. Grandner, Erin C. Hanlon, Alex C. Keene, Michael J. Joyner, Ilia Karatsoreos, Philip A. Kern, Samuel Klein, Christopher J. Morris, Allan I. Pack, Satchidananda Panda, Louis J. Ptacek, Naresh M. Punjabi, Paolo Sessone-Corsi, Frank A. Scheer, Richa Saxena, Elizabeth R. Seaquest, Matthew S. Thimgan, Eve Van Cauter, Kenneth P. Wright

Biological Sciences Faculty Research and Publications

A workshop was held at the National Institute for Diabetes and Digestive and Kidney Diseases with a focus on the impact of sleep and circadian disruption on energy balance and diabetes. The workshop identified a number of key principles for research in this area and a number of specific opportunities. Studies in this area would be facilitated by active collaboration between investigators in sleep/circadian research and investigators in metabolism/diabetes. There is a need to translate the elegant findings from basic research into improving the metabolic health of the American public. There is also a need for investigators studying the impact …

Tradeoffs Of Warm Adaptation In Aquatic Ectotherms: Live Fast, Die Young?, A. P. Porreca, E. Martinez, R. E. Colombo, Michael A. Menze

Faculty Research & Creative Activity

In the face of a changing climate, questions regarding sub-lethal effects of elevated habitat temperature on the physiology of ectotherms remain unanswered. In particular, long-term responses of ectotherms to the warming trend in tropical regions are unknown and significantly understudied due primarily to the difficulties in specimen and community traceability. In freshwater lakes employed as cooling reservoirs for power plants, increased physiological stress from high water temperature can lead to an increase in mortality, reduce growth, and potentially alter the community structure of fishes. Throughout this study, we employ this highly tractable system to assess how elevated thermal regimes can …

Tradeoffs Of Warm Adaptation In Aquatic Ectotherms : Live Fast, Die Young?, A. Porreca, E. Martinez, R. Colombo, Michael Menze

Faculty and Staff Scholarship

In the face of a changing climate, questions regarding sub-lethal effects of elevated habitat temperature on the physiology of ectotherms remain unanswered. In particular, long-term responses of ectotherms to the warming trend in tropical regions are unknown and significantly understudied due primarily to the difficulties in specimen and community traceability. In freshwater lakes employed as cooling reservoirs for power plants, increased physiological stress from high water temperature can lead to an increase in mortality, reduce growth, and potentially alter the community structure of fishes. Throughout this study, we employ this highly tractable system to assess how elevated thermal regimes can …

Polyq-Dependent Rna–Protein Assemblies Control Symmetry Breaking, Changhwan Lee, Patricia Occhipinti, Amy S. Gladfelter

Dartmouth Scholarship

Dendritic growth in fungi and neurons requires that multiple axes of polarity are established and maintained within the same cytoplasm. We have discovered that transcripts encoding key polarity factors including a formin, Bni1, and a polarisome scaffold, Spa2, are nonrandomly clustered in the cytosol to initiate and maintain sites of polarized growth in the fungus Ashbya gossypii. This asymmetric distribution requires the mRNAs to interact with a polyQ-containing protein, Whi3, and a Pumilio protein with a low-complexity sequence, Puf2. Cells lacking Whi3 or Puf2 had severe defects in establishing new sites of polarity and failed to localize Bni1 protein. Interaction …

Saponin-Permeabilization Is Not A Viable Alternative To Isolated Mitochondria For Assessing Oxidative Metabolism In Hibernation, Katherine E. Mathers, James F. Staples

Biology Publications

Saponin permeabilization of tissue slices is increasingly popular for characterizing mitochondrial function largely because it is fast, easy, requires little tissue and leaves much of the cell intact. This technique is well described for mammalian muscle and brain, but not for liver. We sought to evaluate how saponin permeabilization reflects aspects of liver energy metabolism typically assessed in isolated mitochondria. We studied the ground squirrel (Ictidomys tridecemlineatus Mitchell), a hibernating mammal that shows profound and acute whole-animal metabolic suppression in the transition from winter euthermia to torpor. This reversible metabolic suppression is also reflected in the metabolism of isolated liver …

Cytoskeletal Dynamics: A View From The Membrane, Magdalena Bezanilla, Amy S. Gladfelter, David R. Kovar, Wei-Lih Lee

Dartmouth Scholarship

Many aspects of cytoskeletal assembly and dynamics can be recapitulated in vitro; yet, how the cytoskeleton integrates signals in vivo across cellular membranes is far less understood. Recent work has demonstrated that the membrane alone, or through membrane-associated proteins, can effect dynamic changes to the cytoskeleton, thereby impacting cell physiology. Having identified mechanistic links between membranes and the actin, microtubule, and septin cytoskeletons, these studies highlight the membrane’s central role in coordinating these cytoskeletal systems to carry out essential processes, such as endocytosis, spindle positioning, and cellular compartmentalization.

Metabolic Effects Of Bariatric Surgery In Mouse Models Of Circadian Disruption, Deanna M. Arble, Darleen A. Sandoval, Fred W. Turek, Stephen C. Woods, Randy J. Seeley

Biological Sciences Faculty Research and Publications

Background/Objectives:

Mounting evidence supports a link between circadian disruption and metabolic disease. Humans with circadian disruption (for example, night-shift workers) have an increased risk of obesity and cardiometabolic diseases compared with the non-disrupted population. However, it is unclear whether the obesity and obesity-related disorders associated with circadian disruption respond to therapeutic treatments as well as individuals with other types of obesity.

Subjects/Methods:

Here, we test the effectiveness of the commonly used bariatric surgical procedure, Vertical Sleeve Gastrectomy (VSG), in mouse models of genetic and environmental circadian disruption.

Results:

VSG led to a reduction in body weight and fat mass in …

The Effects Of Suspended Sediment On Japanese Medaka (Oryzias Latipes) And Mosquitofish (Gambusia Affinis) Metabolism, Brandy L. Bossle, Ruben R. Goforth, Shem D. Unger, Olin E. Rhodes Jr.

Journal of the South Carolina Academy of Science

Sedimentation is recognized as a significant environmental stressor in aquatic ecosystems and high amounts of suspended sediments (SS) in streams are known to negatively affect aquatic organisms. In particular, it has been hypothesized that many fish species mayexhibit increased respiration rates when exposed to elevated SS. To evaluate this hypothesis, we evaluated the acute response (3 hour exposure) of two small, freshwater fish species exposed to high suspended sediment loads using experimental respirometry chambers which measure oxygen consumption as a proxy of metabolism. Our results indicate that Japanese Medaka (Oryzias latipes) did not exhibit a significantly greater oxygen …

Mechanisms Underlying Weight Loss And Metabolic Improvements In Rodent Models Of Bariatric Surgery, Deanna M. Arble, Darleen A. Sandoval, Randy J. Seeley

Biological Sciences Faculty Research and Publications

Obesity is a growing health risk with few successful treatment options and fewer still that target both obesity and obesity-associated comorbidities. Despite ongoing scientific efforts, the most effective treatment option to date was not developed from basic research but by surgeons observing outcomes in the clinic. Bariatric surgery is the most successful treatment for significant weight loss, resolution of type 2 diabetes and the prevention of future weight gain. Recent work with animal models has shed considerable light on the molecular underpinnings of the potent effects of these ‘metabolic’ surgical procedures. Here we review data from animal models and how …

Changes In Gene Expression In Sirt3 Knockout Liver Cells, Randa Tao, Jamie Leclerc, Kübra Yildiz, Seong-Hoon Park, Barbara Jung, David Gius, Özkan Özden

Turkish Journal of Biology

The sirtuin (SIRT) gene family is reported to regulate critical intracellular processes from aging to cellular metabolism and repair. SIRT3 knockout (SIRT3-/-) mice develop receptor positive mammary tumors starting at 13 months and SIRT3 expression is decreased in human breast cancer samples as well as several other diseases. It is established that carcinogenesis results from the accumulation of multiple aberrant genetic events including the activation of oncogenes and inactivation of tumor-suppressor genes. To determine the potential early genomic events that may play a role in the tumor-permissive phenotype observed in SIRT3-/- cells, we compared gene expression profile in SIRT3-/- and …

Tradeoffs Of Warm Adaptation In Aquatic Ectotherms: Live Fast, Die Young?, Eloy Martinez, Anthony Porreca, Robert Colombo, Michael Menze

Faculty Research & Creative Activity

In the face of a changing climate, questions regarding sub-lethal effects of elevated habitat temperature on the physiology of ectotherms remain unanswered. In particular, long-term responses of ectotherms to the warming trend in tropical regions are unknown, and understudied due to the difficulties in specimen and community traceability. In freshwater lakes employed as cooling reservoirs for power plants, increased physiological stress from high water temperature can potentially alter the community structure of fishes. We employ this highly tractable system to assess how thermal regimes can alter the physiology and ecology of aquatic species. We documented a significantly reduced lifespan, growth …

Global Climate Change And The Southern Ocean: How Antarctic Fishes Physiologically Respond To A Changing Environment From The Cellular To The Organismal Level, Laura A. Enzor

Theses and Dissertations

Studies have projected that future changes in sea surface temperature and pCO2 levels will impact higher latitudes to a greater extent than in temperate regions. For notothenioid fishes of the Southern Ocean, evolution in extremely stable, cold waters has resulted in several adaptations which have left these fishes poorly prepared for global climate change. I have analyzed the metabolic and cellular response of Trematomus bernacchii, Pagothenia borchgrevinki and Trematomus newnesi to a long-term, multi-stressor scenario relevant to the predicted changes in the Southern Ocean. By combining whole animal respirometry with cellular level analysis of energy allocation, osmoregulatory mechanisms and cellular …

A Distinct Tethering Step Is Vital For Vacuole Membrane Fusion, Michael Zick, William T. Wickner

Dartmouth Scholarship

Past experiments with reconstituted proteoliposomes, employing assays that infer membrane fusion from fluorescent lipid dequenching, have suggested that vacuolar SNAREs alone suffice to catalyze membrane fusion in vitro. While we could replicate these results, we detected very little fusion with the more rigorous assay of lumenal compartment mixing. Exploring the discrepancies between lipid-dequenching and content-mixing assays, we surprisingly found that the disposition of the fluorescent lipids with respect to SNAREs had a striking effect. Without other proteins, the association of SNAREs in trans causes lipid dequenching that cannot be ascribed to fusion or hemifusion. Tethering of the SNARE-bearing proteoliposomes was …

Increasing Energetic Cost Of Biosynthesis During Growth Makes Refeeding Deleterious, Chen Hou

Biological Sciences Faculty Research & Creative Works

Diet restriction (DR) enhances animals' health maintenance, but refeeding reverses its beneficial effects. However, to what degree refeeding reverses the beneficial effects of DR remains controversial. Here, I develop a theoretical model for reconciling the results of refeeding studies and understanding the dynamic and reversible mechanism underlying the effects of diet on health from the energetic viewpoint. By illustrating the negative correlation between health maintenance and the energetic cost of growth in animals under different diet regimes, the model explains why, in some cases, refed animals have better health and live longer than freely fed controls. More importantly, the model …

New Frontiers For The Nfil3 Bzip Transcription Factor In Cancer, Metabolism And Beyond, Megan Keniry, Robert K. Dearth, Michael W. Persans, Ramon Parsons

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The bZIP transcription factor NFIL3 (Nuclear factor Interleukin 3 regulated, also known as E4 binding protein 4, E4BP4) regulates diverse biological processes from circadian rhythm to cellular viability. Recently, a host of novel roles have been identified for NFIL3 in immunological signal transduction, cancer, aging and metabolism. Elucidating the signaling pathways that are impacted by NFIL3 and the regulatory mechanisms that it targets, inhibits or activates will be critical for developing a clearer picture of its physiological roles in disease and normal processes. This review will discuss the recent advances and emerging issues regarding NFIL3-mediated transcriptional regulation of CEBPb and …

Antimicrobial And Antiinsectan Phenolic Metabolites Of Dalea Searlsiae, Gil Belofsky, Mario Aronica, Eric Foss, Jane Diamond, Felipe Santana, Jacob Darley, Patrick F. Dowd, Christina M. Coleman, Daneel Ferreira

All Faculty Scholarship for the College of the Sciences

Continued interest in the chemistry of Dalea spp. led to investigation of Dalea searlsiae, a plant native to areas of the western United States. Methanol extractions of D. searlsiae roots and subsequent chromatographic fractionation afforded the new prenylated and geranylated flavanones malheurans A–D (1–4) and known flavanones (5 and 6). Known rotenoids (7 and 8) and isoflavones (9 and 10) were isolated from aerial portions. Structure determination of pure compounds was accomplished primarily by extensive 1D- and 2D-NMR spectroscopy. The absolute configurations of compounds 1–5, 7 …