Cell Biology Commons^™

Mitochondrial Roles In Developmentally Programmed Heart Disease, Eli John Louwagie

Dissertations and Theses

Offspring of diabetic and obese mothers (ODOM) have greater risks of heart disease at birth and later in life. However, prevention is hindered because underlying mechanisms are poorly understood. Mounting studies in the Developmental Origins of Health and Disease field suggest that mitochondria play key roles in developmentally programmed heart disease similar to the roles they play in cardiomyopathy in adults with diabetes and obesity. However, whether mitochondria are responsible for the short[1]and long-term cardiac disease seen in ODOM remains unknown. Here, we sought to delineate the roles of mitochondria in the hearts of ODOM, determine whether mitochondria are playing …

E-Cadherin Force Transmission And Stiffness Sensing, Mazen Mezher

Mechanical & Aerospace Engineering Theses & Dissertations

E-cadherin is the chief mediator of cell-cell adhesion between epithelial cells and is a known mechanosensor. Force transmission and stiffness sensing are two crucial aspects of E-cadherin mechanobiology.

E-cadherin has an extracellular adhesive region, a transmembrane region and an intracellular region that binds to adhesion-associated proteins. Here, we assessed how different factors affect the level of force transmission (i) from inside the cell such as adhesion-associated proteins, (ii) on the cell membrane, such as growth factor receptors and (iii) outside the cell, such as different binding partners in adhesion. To study the level of force transmission inside the cell, we …

Cardiac Ablation And Stimulation With Nanosecond Pulsed Electric Fields (Nspefs), Federica Serra

Biomedical Engineering Theses & Dissertations

Surgical ablation of cardiac tissue is the definitive treatment for the most common arrhythmia, atrial fibrillation. In current medical practice, myocardial tissue is often ablated by the application of radiofrequency (RF) currents which are delivered through an electrode to create lesions that block the electrical pathways that sustain reentrant arrhythmias and restore the normal heart rhythm. An alternative to RF is cryoablation, during which the endocardial or epicardial tissue is brought in contact with a cryoprobe. Both RF ablation and cryoablation have significant limitations. In RF ablation, tissue is heated in order to ablate it, but it is an open …

Examining Transcriptional Regulators During Muscle Development In Drosophila Melanogaster, Chaamy Yapa

Student Theses and Dissertations

In Drosophila melanogaster embryos, a distinct approach to study the transcriptional regulation is to examine the larval somatic muscle development. Transcription factors are essential regulatory proteins that help to control gene expression and respond to signaling pathways and various cues. Today, there are at least twenty transcription factors that have been discovered to contribute to the development of the 30 distinct larval somatic muscles in each abdominal hemisegment of Drosophila melanogaster. Several studies have already been conducted on muscle regulatory transcription factors including midline and apterous. These transcription factors were shown to control the development of muscles through mutant …

Validating A New In Vivo Model To Study Als, Izabela J. Cimachowska

Student Theses and Dissertations

Buildup of oxidative stress and mitochondrial dysfunction are well known characteristics of both sporadic and hereditary amyotrophic lateral sclerosis (ALS). While both forms of the disease seem to arise from common cellular dysfunction, the genetic disease is studied to a much greater extent. Engineering novel animal models of the sporadic form of the disease is crucial for development of druggable targets to treat ALS and understand the underlying mechanisms. Interestingly, accumulation of oxidative stress by exacerbated emission of reactive oxygen species (ROS) from presynaptic mitochondria is a hallmark of both hereditary and sporadic ALS. Previous work by our laboratory showed …

Methyltransferase, Glucose Adaptation, And Import Complex In Trypanosoma Brucei, Emily Knight

All Dissertations

Trypanosoma brucei is a kinetoplastid parasite responsible for human African trypanosomiasis (HAT) and nagana, a livestock wasting disease, which both endemic to sub-Saharan Africa. Unique to kinetoplastids are the specialized peroxisomes, named glycosomes, which compartmentalize the first several steps of glycolysis and gluconeogenesis, nucleotide sugar biosynthesis, and many other metabolic processes. Kinetoplastids are unique in that they have a single mitochondrion. In this work, I present the first study into SET domain proteins in any kinetoplastid parasites. We have characterized a predicted SET domain protein, TbSETD3, that localizes to the mitochondrion and a depletion of the protein results in growth …

Minimal Carbon Requirements For Potential Colonizers Of Other Planets, Benjamin Tan

Biological Sciences Undergraduate Honors Theses

The NASA Office of Planetary Protection regulates the safe scientific exploration of other planets. Specifically, the office enacts rules to discourage interplanetary mission practices that would lead to the contamination of Earth-originating microbial life on other planets. Interplanetary contamination jeopardizes the potential to obtain reliable scientific evidence for extraterrestrial life. In coordination with this office, the biosignatures of potential colonizers of other celestials bodies are studied. Several organisms of Earth qualify as potential colonizers of other planets.

This experiment focused on the environment of Mars in particular. Two organisms were tested: Desulfovibrio arcticus and Desulfotalea psychrophila. Both are psychrotolerant or …

Serum Amyloid A Augments The Atherogenic Effects Of Cholesteryl Ester Transfer Protein, Ailing Ji, Andrea C. Trumbauer, Victoria P. Noffsinger, Frederick C. De Beer, Nancy R. Webb, Lisa R. Tannock, Preetha Shridas

Saha Cardiovascular Research Center Faculty Publications

Serum amyloid A (SAA) is predictive of CVD in humans and causes atherosclerosis in mice. SAA has many proatherogenic effects in vitro. However, HDL, the major carrier of SAA in the circulation, masks these effects. The remodeling of HDL by cholesteryl ester transfer protein (CETP) liberates SAA restoring its proinflammatory activity. Here, we investigated whether deficiency of SAA suppresses the previously described proatherogenic effect of CETP. ApoE¡/¡ mice and apoE¡/¡ mice deficient in the three acute-phase isoforms of SAA (SAA1.1, SAA2.1, and SAA3; “apoE¡/¡ SAA-TKO”) with and without adeno-associated virus-mediated expression of CETP were studied. There was no effect of …

Cytotoxic Effects Of Bpa And Dehp On Human Epithelial Cells, Noah Stickrod

Theses/Capstones/Creative Projects

Endocrine disrupting chemicals (EDCs) are substances in the environment, food sources, personal care products, and manufactured products that interfere with the normal function of the body’s endocrine system. Most humans are exposed to some amount of these chemicals from many different sources, such as the air we breathe, food we eat, and the water we drink. EDCs can also permeate through the skin. The endocrine system is important because it works with other systems in the body to ensure healthy development and function throughout life. EDCs interfere with the way our body’s hormones work. Some EDCs can mimic natural hormones …

Adipocytes And Innate Immunity In Systemic Sclerosis, Nancy Wareing

Dissertations and Theses (Open Access)

Systemic sclerosis (SSc; scleroderma) is a chronic systemic autoimmune and connective tissue disorder characterized by vasculopathy, autoimmune phenomena, and widespread fibrosis. Skin thickening and tightening is the cardinal feature of SSc and is responsible, in part, for the considerable morbidity of this disease. There are currently no targeted treatments for skin manifestations in SSc, primarily due to our fragmented understanding of its pathophysiologic mechanisms. In PART I, we report a previously unappreciated link between aberrant expression of the developmental gene sine oculis homeobox homolog 1 (SIX1) in skin-associated adipocytes in SSc skin and the early loss of dermal white adipose …

Targeting Metabolic Alterations Associated With Smooth Muscle Α-Actin Pathogenic Variant Attenuates Moyamoya-Like Cerebrovascular Disease, Anita Kaw

Dissertations and Theses (Open Access)

Heterozygous pathogenic variants in ACTA2, encoding smooth muscle α-actin (α-SMA), predispose to thoracic aortic aneurysms and dissections. De novo missense variants disrupting ACTA2 arginine 179 (p.Arg179) cause a multisystemic disease termed smooth muscle dysfunction syndrome (SMDS), which is characterized by early onset thoracic aortic disease and moyamoya disease-like (MMD) cerebrovascular disease. The MMD-like cerebrovascular disease in SMDS patients is marked by bilateral steno-occlusive lesions in the distal internal carotid arteries (ICAs) and their branches. To study the molecular mechanisms that underlie the ACTA2 p.Arg179 variants, a smooth muscle-specific Cre-lox knock-in mouse model of the heterozygous Acta2 R179C variant, termed …

Regulation Of De Novo And Maintenance Dna Methylation By Dnmt3a And Dnmt3b, Yang Zeng

Dissertations and Theses (Open Access)

DNA methylation (5-methylcytosine, 5mC) is essential for the regulation of gene expression and integrity of the mammalian genome. It occurs predominantly in the context of CpG dinucleotides to form a symmetrical pattern on both DNA strands, which allows DNA methylation patterns to be semi-conservatively maintained during DNA replication. There are two classes of DNA methyltransferases (DNMTs): DNMT3A and DNMT3B function primarily as de novo methyltransferases that establish DNA methylation patterns, whereas DNMT1 is the major enzyme responsible for maintaining DNA methylation patterns by converting hemi-methylated CpGs to fully methylated CpGs during DNA replication. Two accessory factors also play critical regulatory …

Regulation And Function Of Zeb1 Acetylation In Lung Adenocarcinoma Progression And Metastasis, Mabel Perez-Oquendo

Dissertations and Theses (Open Access)

Lung cancer metastasis is leading the causes of cancer-related mortality in the United States and worldwide. Epithelial-to-mesenchymal transition (EMT) is a model for metastasis that results in loss of specialized epithelial cell contacts and acquisition of mesenchymal invasive capacity. Zinc finger E-box-binding homeobox 1 (ZEB1) recognizes and binds to E-boxes of epithelial gene promoters to repress its transcription. ZEB1 has inconsistent molecular weights, which have been attributed to post-translational modifications (PTMs). In the presented dissertation, I specifically addressed the gap in the molecular mechanisms by which PTMs of ZEB1 regulate its ability to induce EMT and how its activity might …

Development Of A Novel Fluorescent Reporter Baculovirus Vector For Testing Promoters In Lepidopterans, Daniel Howard

All Theses

Testing gene expression patterns is an important process in learning more about an organism. The standard methods of rtPCR and RNASeq provide highly detailed data on specific expression patterns, but can be resource consuming if many different samples including genes or organisms must be tested. A potential alternative for studying expression is the use of a reporter system carried by a vector system that encodes fluorescent proteins under the control of promoters of interest. Many lepidopterans (moths) are pestiferous and better understanding of gene expression levels in lepidopterans, both endogenous and exogenous including from their viruses, would be beneficial. Baculoviruses …

Investigation The Plugging Behavior Of Virus Filters, Iman Abdulqader Saab

Graduate Theses and Dissertations

A virus filtration step is integral to the manufacturing of biopharmaceuticals to ensure viral safety. A virus filter is a single-use device that uses a size-based separation process and has a unique structure with minimal defects, so that contaminating virus particles cannot pass through the membrane pores, while therapeutic molecules can. The development of novel antibodies (Abs), including significant increases in product titers, is frequently challenged by virus filter fouling, making a better understanding of the underlying mechanisms essential. This thesis focused investigating of the effect of prefilter types, buffer type and salt content on virus filtration performance. The impact …

Understanding The Expression And Role Of Pros-1 In The Male Gonad Of C. Elegans, Jack Bozik

Undergraduate Theses

The gene pros-1 is a transcription factor that is highly expressed within neuronal sheath cells, glial cells, and excretory canal cells. pros-1 plays a role in cell determination of those cell types in the nematode C. elegans, which promotes organismal development. But the degree to which pros-1 presence is important is still not fully understood, because there are many genes involved in development that when mutated or damaged can result in unexpected phenotypes or even total loss of function to a certain developmental mechanism. What makes pros-1 valuable to research is that it is a functional homologue to a …

Distribution Of Micropredators In The Longleaf Pine Soil Microbiome, Faith Arends, Eithar Mirghani

Symposium of Student Scholars

Bacterial micropredators of the soil, like their larger-scale counterparts, play a key role in shaping their ecosystem and are thus of particular interest from an ecological standpoint. An important micropredator to study are Myxobacteria. Myxobacteria are gram-negative rod-shaped social bacteria that hunt in wolf packs to lyse their prey and facilitate their growth. Myxobacteria are a potential source of novel antibiotics, therefore, the isolation of new strains is of great interest. We investigated longleaf pine soil as a source of novel isolates. The Longleaf Pine Ecosystem is an endangered ecosystem that is of crucial importance due to its ability to …

Pyrus Calleryana Extracts Reduce Germination Of Native Grassland Species, Suggesting The Potential For Allelopathic Effects During Ecological Invasion, Michaela J. Woods, Jonathan T. Bauer, Dena Schaeffer, Ryan W. Mcewan

Biology Faculty Publications

Invasive plant species’ success may be a result of allelopathy, or the release of secondary metabolites that are harmful for surrounding plant species. Allelopathy can be mediated through the abiotic environment by chemical sorption or transformation, so the substrate on which interactions occur can lead to differential outcomes in allelopathic potential. One aggressive invader, Pyrus calleryana, has become dominant in many ecosystems throughout Eastern US, and has reduced the abundance of native species where it invades. Thus, our goal was to identify if P. calleryana had allelopathic potential by testing the impact of leaf and flower leachate on gemination …

Characterization Of Toxoplasma Gondii Calcium Regulator Proteins Tggt1_253640 And Tggt1_222060 For Toxoplasma Gondii Growth And Invasion, Abigail Delapenha

Departmental Honors & Graduate Capstone Projects

Toxoplasma gondii is an opportunistic apicomplexan parasite infecting humans and livestock. Infection in immunocompromised individuals can cause neurological damage and infection during pregnancy can lead to fetal death. These parasites engage in a complex life cycle, involving repeated invasion of the host cell and egress from the host cell. Calcium signaling is an important regulatory mechanism for many essential processes in the parasite, including gliding motility (actomyosin-dependent mode of motion), invasion, and egress. Our work here focuses on two previously uncharacterized calcium regulator proteins (TGGT1_253640 and TGGT1_222060). To characterize the role of these proteins in parasite viability and calcium regulation, …

Studies On Osh6 And Its Pro-Aging Mechanisms, Nazneen Begum

Theses and Dissertations

The target of rapamycin complex 1 (TORC1) is a master regulator of cell growth as well as a negative regulator of longevity. A recent study in yeast showed that the vacuolar TORC1 stimulates protein synthesis and cell growth while the endosomal TORC1 inhibits autophagy, a pro-longevity process. Since late endosome frequently exchanges membranes with vacuoles, the spatial dissection of TORC1 raises an interesting question as to how to inhibit the endosomal TORC1 and boosts the vacuolar TORC1 to extend the health span. In my thesis, I employed a longevity mutant that mildly up-regulates Osh6 (PERG6-OSH6) to address this question. I …