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The Role Of Parkin In Mitochondrial Dna, Eliezer Lichter

Theses & Dissertations

Mitochondria are at the center of biological phenomena such as aging and diseases, especially neurodegenerative diseases. While the discovery of mitochondria only came approximately 200 years after the cell was discovered, a lot of progress has been made since. The mitochondrial genome encodes proteins vital for mitochondrial function. These proteins are only a subset of the proteins present in mitochondria; the rest are nuclear encoded. The nucleus also encodes cytosolic proteins vital for mitochondrial maintenance. One of these is Parkin, an E3 ubiquitin ligase that ubiquitinates mitochondrial proteins as mitochondria become depolarized. Its activity has been shown to be involved …

Dpc29 Promotes Mitochondrial Translation Post-Initation In Saccharomyces Cerevisiae, Kyle Andrew Hubble

Graduate School of Biomedical Sciences Theses and Dissertations

Although the cytosolic and bacterial translation systems are well studied, much less is known about translation in mitochondria. In the yeast Saccharomyces cerevisiae, mitochondrial gene expression is predominately regulated by translational activators. These regulators are thought to promote translation by binding the elongated 5’-UTRs on their target mRNAs. Since mammalian mitochondrial mRNAs generally lack 5’-UTRs, they must regulate translation by other mechanisms. As expected, most yeast translational activators lack orthologues in mammals. Recently, a mitochondrial gene-specific translational activator, TACO1, was reported in mice and humans. To better define its role in mitochondrial translation I examined the yeast TACO1 orthologue, DPC29. …

Ankyrin Dependent Mitochondrial Function And Bioenergetics In The Heart, Janani Subramaniam, Janani Subramaniam

Dissertations & Theses (Open Access)

ANK2 mutations in patients are associated with numerous arrhythmias, cardiomyopathies, and other heart defects. In the heart, AnkB, the protein encoded by ANK2, clusters relevant ion channels and cell adhesion molecules in several important domains; however, its role at Mitochondria Associated ER/SR Membranes (MAMs) has yet to be investigated. MAMs are crucial to mitochondrial function and metabolism and are signaling hubs implicated in various cardiac pathologies. Among several functions, these sites mediate the direct transfer of calcium from the ER/SR to the mitochondria to modulate ATP synthesis. Given that mitochondrial function and energy production are paramount to cardiovascular heath, …

Elucidating The Mechanisms Underlying How Vmp1 Regulates Inflammatory Responses, Stephanie Zack

Dissertations

autophagy, inflammation, mitochondria, NLRP3 inflammasome, SERCA, VMP1

Mechanisms And Roles Of Dynamic Actin Assembly Around Dysfunctional Mitochondria, Tak Shun Fung

Dartmouth College Ph.D Dissertations

Possessing the ability to efficiently generate ATP required to sustain cellular functions, mitochondria are often considered the ‘powerhouses of the cell’. However, our understanding of mitochondria in cell biology was further expanded when we recognized that communication between this unique organelle and the rest of the cell regulates cellular bioenergetics, metabolism and signaling processes such as mitophagy and apoptosis. Here, I investigate signaling between mitochondria and the actin cytoskeleton, and how this signaling regulates mitochondrial dynamics and cellular function. Specifically, I find that, upon mitochondrial dysfunction, actin polymerizes rapidly around the dysfunctional organelle, which we term ‘acute damage-induced actin’ (ADA). …

Sex Differences In Cancer Cachexia And A Novel Mitochondrial Target For Cancer-Induced Muscle Wasting, Seongkyun Lim

Graduate Theses and Dissertations

Cancer cachexia (CC) is a devastating wasting syndrome characterized by marked weight loss including skeletal muscle atrophy that affects approximately 80% of cancer patients. Current therapeutic treatments including pharmacological and nutritional intervention are insufficient to prevent or reverse it. Prior studies demonstrated lower muscle mass, impaired muscle function, and mitochondrial health in the development of CC. Specifically, mitochondrial fusion protein, Optic atrophy 1 (OPA1) which plays a significant role in skeletal muscle health, is suppressed in the development of CC. Furthermore, most pre-clinical CC studies were mainly focused on males although there are distinct phenotypical differences in skeletal muscle between …

Characterization Of Larval Lepidopteran Gut Stem Cell Markers, Zilan Li

All Theses

The larval lepidopteran midgut is a complex tissue system that shows significant structure-function relationships related to its roles in digestive and absorptive processes. δ-endotoxins (Cry toxins) produced by the bacterium Bacillus thuringiensis disrupt the midgut epithelium of target insects has been used extensively to control pests. However, insects, including several lepidopteran species, evolve resistance to Cry toxins which causes a great threat to their continued utility. Understanding the physiology of the midgut, including that of the stem cells which are responsible for midgut growth, development, and regeneration, may improve the sustainability of midgut-targeted control like Cry toxins. Historically, lepidopteran midgut …

The Role Of Calprotectin In T-Lymphocyte Driven Inflammation In A Mouse Model Of Psychological Trauma, Cassandra Moshfegh

Theses & Dissertations

Post-traumatic stress disorder (PTSD) is a debilitating psychological disorder that affects nearly 45 million Americans. This mental disorder is characterized by behavioral symptoms such as learned helplessness, hyperarousal, withdrawal, and flashbacks. The deleterious effects of PTSD are far-reaching and go beyond behavioral dysfunction, as these individuals are at a three-fold higher risk of comorbid inflammatory diseases. Autonomic, metabolic, and cardiovascular diseases plague these individuals later in their lifetime, however, the mechanistic link connecting psychological trauma to this systemic peripheral immunological dysfunction remains elusive. T-lymphocyte-induced inflammation plays a significant role in all these disease pathologies. Previous work from our laboratory demonstrated …

Role Of Mitochondria In Postmortem Proteolysis And Meat Tenderness, David Son Dang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Among all eating quality characteristics in beef, tenderness is regarded as one of the most important traits. Previous research indicates that consumers are willing to pay a premium for beef guaranteed to be tender. Yet, tenderness is difficult to control and predict as it is influenced by a multitude of factors. Among these factors, meat aging has been shown to be a strong determinant of tenderness. Meat aging describes a process in which muscle tissue is broken down by other proteins within the muscle, resulting in a more tender product after cooking. Two well-recognized proteins that participate in the breakdown …

Studying Acetylation Of Aconitase Isozymes By Genetic Code Expansion, Jessica Araujo

Graduate Theses and Dissertations

The tricarboxylic acid (TCA) cycle is a very important, centrally located, energy-producing pathway that connects numerous other metabolic and regulatory pathways. Enzymes of this cycle have been more recently implicated in various cancers and neurometabolic disorders, however, the exact mechanism by which this happens becomes quite complex when considering the potential modification of these enzymes and the presence of multiple forms of the enzymes and therefore there is much to be studied in this area.

Aconitase has become a recent enzyme of interest as its substrate, citrate, has been found to play a major role in many vital processes within …

Using Fluorescent Microscopy To Follow Mitochondrial Inheritance Through Tagged Alternative Oxidase In Sporisorium Reilianum., Luke Schroeder

College of Arts & Sciences Senior Honors Theses

Sporisorium reilianum is a dimorphic fungus that inhabits and infects a host corn plant (Zea mays). In order for the fungus to reproduce sexually, compatible haploid mating types must form a dikaryon that goes on to cause infection in the host. This infection causes leaf chlorosis and gall formation, while ultimately allowing for the dispersal of fungal teliospores in the later stages of infection. To grow, the fungus requires energy production in the form of ATP from its mitochondria. As a countermeasure to infection, host plants release harsh reactive oxygen species that may damage DNA, lead to apoptosis, …

Role Of Galactose, Thiazolidinediones, And Neet Proteins In Mitochondrial Physiology And Therapeutic Development., Robert Anthony Skolik

Electronic Theses and Dissertations

This dissertation explores the relationship between mitochondrial physiology and development of therapeutics. Mitochondrial dysfunction is associated with both acute and chronic forms of pathophysiology. This work aims to address development efforts at the cell culture and drug-target levels with respect to mitochondria. At the cell culture level, I characterize an approach that has been shown to improve the physiological dependency on mitochondria in tumor-derived cells. I demonstrate that prolonged replacement of glucose with galactose in culture medium induces a global metabolic shift in hepatocellular carcinoma (HepG2) cells to closer reflect a primary hepatocyte phenotype (Chapter 2). I characterize this shift …

The Roles Of Pon2 In Mitochondrial Physiology, Lung Tumor Cell Proliferation, And Lung Tumorigenesis., Aaron Whitt

Electronic Theses and Dissertations

Paraoxonase 2 (PON2) is an intracellular, multifunctional enzyme with near-ubiquitous tissue distribution. Within cells, PON2 is localized to mitochondria and endoplasmic reticulum (ER), where it mitigates the formation of reactive oxygen species (ROS). PON2’s chief enzymatic function is its lactonase activity, through which it catalyzes the hydrolysis of a bacterial quorum-sensing molecule, N-(3-oxododecanoyl)-l-homoserine lactone (C12), effectively disrupting bacterial intercellular communication and protecting against infection. C12 is produced by the opportunistic pathogen Pseudomonas aeruginosa and has been shown to disrupt various aspects of eukaryotic host cell physiology and evoke apoptotic cell death through the activity of PON2. Additionally, PON2 has garnered …

Role Of Bmi1 In Acute Lung Injury, María Helena Hernández-Cuervo

USF Tampa Graduate Theses and Dissertations

Acute Lung Injury (ALI) is a set of signs and symptoms that lead to acute hypoxemic respiratory failure characterized by bilateral pulmonary infiltrates not attributed to cardiogenic origin. It is caused by a massive innate immune response, with the migration of white blood cells (neutrophils and macrophages principally) and a cytokine storm, followed by alterations in mitochondrial function, increase in reactive oxygen species production, and oxidative stress that in turn induces more mitochondrial damage. Several studies have shown that mitochondrial alterations are key events in the mechanism of ALI and reducing mitochondrial dysfunction could be a possible target in the …

Mechanisms Of Diapause And Cold Tolerance In The Colorado Potato Beetle, Jacqueline E. Lebenzon

Electronic Thesis and Dissertation Repository

Many temperate insects enter diapause (a state of dormancy) and enhance their cold tolerance to survive the winter. During diapause, the Colorado potato beetle (CPB, Leptinotarsa decemlineata, Coleoptera: Chrysomelidae) stops developing, lowers its metabolism, and changes its physiology to avoid freezing. The extent to which diapause confers cold tolerance in CPB is currently unknown. In my thesis, I used CPB to improve our understanding of the mechanisms underlying metabolic suppression during diapause and cellular protection at sub-zero temperatures in insects. First, I used RNA-sequencing (RNA-seq) to compare gene expression in two metabolically important tissues (the fat body and flight muscle) …