Cell Biology Commons^™

Analysis Of Adult Neural Retina Extracellular Vesicle Release, Rna Transport And Proteomic Cargo, Jason Mighty, Jing Zhou, Alberto Benito-Martin, Sami Sauma, Samer Hanna, Onyekwere Onwumere, Cui Shi, Martin Muntzel, Moira Sauane, Michael Young, Henrik Molina, Dianne Cox, Stephen Redenti

Publications and Research

PURPOSE. Extracellular vesicles (EVs) contain RNA and protein cargo reflective of the genotype and phenotype of the releasing cell of origin. Adult neural retina EV release, RNA transfer, and proteomic cargo are the focus of this study.

METHODS. Adult wild-type mouse retinae were cultured and released EV diameters and concentrations quantified using Nanosight. Immunogold transmission electron microscopy (TEM) was used to image EV ultrastructure and marker protein localization. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to analyze retinal cell transcripts present in EVs. Super-resolution microscopy was used to image fluorescent (green) RNA and (red) lipid membrane labeled EVs, released …

The Effect Of Ph On Synaptic Transmission At The Neuromuscular Junction In Drosophila Melanogaster, Catherine Elizabeth Stanley

Theses and Dissertations--Biology

Synaptic transmission is the main avenue of neuronal communication and can be affected by a multitude of factors, both intracellularly and extracellularly. The effects of pH changes on synaptic transmission have been studied for many years across many different models. Intracellular acidification at the presynaptic terminal is known to occur with increased neuronal activity and can also occur in pathological conditions. The effects of these pH alterations are therefore an important area of study. Here, intracellular acidification using either propionic acid or the ammonium chloride pre-pulse technique was examined for the effects on both spontaneous and evoked synaptic transmission at …

The Roles Of Polar Cell Extensions In Drosophila Micropyle Formation, Bradford Hull

Theses and Dissertations--Biology

The Drosophila micropyle is a conserved formation utilized to allow sperm passage past the robust eggshell structure for fertilization. Micropyle formation follows a unique acellular tubulogenesis method where it is secreted and shaped by specialized follicle cells including the border cells and polar cells. In late oogenesis, the polar cells form extensions that are necessary to create the micropyle pore through which sperm enters. Previous work established that polar cell extension presence is required for micropyle pore formation. We investigated temporal requirements of extensions throughout chorion deposition and found extensions are required during the beginning and middle of choriogenesis, but …

Lps, A Tlr-4 Agonist And Viper A Tlr-4 Inhibitor Upregulate Phagocytosis Of Zymosan In Bv2 Cells, Sherouk Alzeory

Dissertations and Theses

Microglia cells are the first line of innate immunity defense in the central nervous system (CNS). They play a critical role in maintaining CNS homeostasis by having an active but yet balanced phagocytic activity. However, in various CNS related diseases, microglia cells have been shown to malfunction. In Alzheimer's Disease (AD), hyperactive microglia with impaired phagocytic activity is the main hallmark of this disease, along with the accumulation of amyloid-beta aggregates. Additionally, emerging new studies have suggested a fungal infection etiology to AD, specifically in relation to Candida albicans (C.albicans). Thus, understanding the mechanism of fungal clearance in the …

The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nanotechnology takes advantage of cellular biology’s natural nanoscale operations by interacting with biomolecules differently than soluble or bulk materials, often altering normal cellular processes such as metabolism or growth. To gain a better understanding of how copper nanoparticles hybridized on cellulose fibers called carboxymethyl cellulose (CMC) affected growth of Saccharomyces cerevisiae, the mechanisms of toxicity were explored. Multiple methodologies covering genetics, proteomics, metallomics, and metabolomics were used during this investigation. The work that lead to this dissertation discovered that these cellulosic copper nanoparticles had a unique toxicity compared to copper. Further investigation suggested a possible ionic or molecular mimicry …

Role Of Ciliary Proteins Adp Ribosylation Factor Like Gtpase 13b (Arl13b) And Bardet-Biedl Syndrome-8 (Bbs8) In Photoreceptor Outer Segment Morphogenesis, Maintenance, And Viability, Tanya L. Dilan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Photoreceptor neurons are modified primary cilia with an extended ciliary compartment known as the outer segment (OS). The mechanisms behind the elaboration of photoreceptor cilia, OS morphogenesis, and maintenance remain poorly understood. In this work, we focused on dissecting the role of two ciliary proteins, the small GTPase ADP-ribosylation factor-like GTPase 13B (ARL13B) and Bardet-Biedl Syndrome-8 (BBS8) in the context of photoreceptor biology. Both BBS8 and ARL13B are linked to defects in ciliogenesis (cilia development) and Retinitis Pigmentosa (vision loss). ARL13B is implicated in regulating ciliary length, and BBS8 is part of the Bardet-Biedl Syndrome complex (BBSome); the BBSome is …

Evidence Of Y Chromosome Long Non-Coding Rnas Involved In The Radiation Response Of Male Non-Small Cell Lung Cancer Cells, Tayvia Brownmiller

Graduate Theses, Dissertations, and Problem Reports (ETD)

Non-small cell lung cancer (NSCLC) is the number one cause of cancer related mortality in the United States and worldwide. Advanced and therapeutically resistant lung tumors contribute to the high rate of mortality from NSCLC, therefore there is a need for new methods of diagnosing and treating this disease. Long non-coding RNAs (lncRNAs) have been shown to be a crucial component of human molecular biology, regulating nearly every cellular pathway from chromatin condensation to transcription and translation. Furthermore, many lncRNAs have been classified as oncogenes or tumor suppressors, highlighting the various molecular mechanisms they are involved in regarding the formation …

Design, Synthesis, And Characterization Of Chemical Tools To Study Peroxisomal Import, Jhalak N. Timilsena

Masters Theses

Peroxisomes are dynamic and interconnected single lipid membrane bound organelles found in the eukaryotic cells which are involved in various biochemical processes including the b-oxidation of very long chain and branched chain fatty acids, metabolism of reactive oxygen and nitrogen species, and reduction of hydrogen peroxide among others. These organelles are known to host numerous proteins and enzymes depending on the cellular environment. All of the proteins needed in the peroxisomes are encoded in the nucleus and synthesized in the cytosol which are then transported to the peroxisomes with the help of a sophisticated protein-transport machinery. Pex5 is one of …

Actin Regulation And Furrow Dynamics During Early Drosophila Embryogenesis, Yi Xie

Electronic Theses and Dissertations

Drosophila embryogenesis starts with a single nucleus undergo 13 rounds of nuclear divisions called syncytial cycles. Staring at cycle 10 when nuclei migrate to the surface of the embryo, massive and dynamic cortical actin structures and cleavage furrow formations occur. How actin regulators coordinate into an organized network directing three-dimension actin structures in the developing organisms is an unsolved question. Here, I present an in-depth characterization of actin cap dynamics: the actin caps go through expansion, stabilization, elongation and fragmentation phases in each cycle. Arp2/3 is the major contributor to actin cap formation. The functions of 7 different actin and …

Higher Tensile Forces Across Cellular Junctions And An Intact Nuclear Linc Complex Is Required For Epithelial Function And Stability, Fnu Vani Narayanan

Theses and Dissertations

Recent advances in three-dimensional (3D) cell culture systems have provided key insights into the understanding of biochemical and physiological states of native tissue. A significant progress in the field of mechanobiology involves measuring cellular traction forces in a more native 3D environment. However, the effects of mechanical forces exerted across cellular junctions and the nuclear LINC complex, in an organized 3D system has not been investigated thus far. Epithelial cells spontaneously form acini (also known as cysts or spheroids) with a single, fluid-filled central lumen, when grown in 3D matrices. The size of the lumen is dependent on apical secretion …

The Impact Of Aging And Mechanical Injury On Alveolar Epithelial And Macrophage Responses In Acute Lung Injury And Inflammation, Michael S. Valentine

Theses and Dissertations

Patients with severe lung pathologies, such as Acute Respiratory Distress Syndrome (ARDS), often require mechanical ventilation as a clinical intervention; however, this procedure frequently exacerbates the original pulmonary issue and produces an exaggerated inflammatory response that potentially leads to sepsis, multisystem organ failure, and mortality. This acute lung injury (ALI) condition has been termed Ventilator-Induced Lung Injury (VILI). Alveolar overdistension, cyclic atelectasis, and biotrauma are the primary injury mechanisms in VILI that lead to the loss of alveolar barrier integrity and pulmonary inflammation. Stress and strains during mechanical ventilation are believed to initiate alveolar epithelial mechanotransduction signaling mechanisms that contribute …

Sphingolipids In Cancer Health Disparities And As Prospective Targets For Cancer Therapy, April E. Boyd

Theses and Dissertations

Lung cancer is the deadliest cancer both in the United States and worldwide. Non-small cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancers. However, lung cancer disparities are not shared equally across racial groups, with large differences between African American and Caucasian populations. Advances in research have revealed roles of lipid mediators in cancer biology and disease progression, but sphingolipid alterations in tissues should be explored further. To address this, using mass spectrometry (MS), extensive sphingolipidomic characterization of NSCLC tumors and adjacent uninvolved tissues from African American and Caucasian patients were performed. This study revealed that NSCLC …

Granulosa Cell Proliferation Is Inhibited By Pge2 In The Primate Ovulatory Follicle, Patric S. Lundberg, Gil J. Moskowitz, Carmel Bellacose, Esra Demirel, Heidi A. Trau, Diane M. Duffy

Computer Science Faculty Publications

Prostaglandin E2 (PGE2) is a key paracrine mediator of ovulation. Few specific PGE2-regulated gene products have been identified, so we hypothesized that PGE2 may regulate the expression and/or activity of a network of proteins to promote ovulation. To test this concept, Ingenuity Pathway Analysis (IPA) was used to predict PGE2-regulated functionalities in the primate ovulatory follicle. Cynomolgus macaques underwent ovarian stimulation. Follicular granulosa cells were obtained before (0 h) or 36 h after an ovulatory dose of human chorionic gonadotropin (hCG), with ovulation anticipated 37-40 h after hCG. Granulosa cells were obtained from additional monkeys 36 h after treatment with …

Investigation Of Rna Interference (Rnai)-Mediated Gene Silencing In Rainbow Trout, Sarah Au

Theses and Dissertations (Comprehensive)

RNA interference (RNAi) was first characterized in plants and invertebrates as an antiviral innate immune response. It is a natural antiviral defence mechanism to degrade viral RNA by virus-induced gene silencing. Studies showed synthetic long double-stranded RNA (dsRNA; >30bp) degraded Caenorhabditis elegans messenger RNA (mRNA) transcripts, resulting in sequence-dependent gene silencing. Currently, there is only limited research on RNAi in fish, particularly the use of long dsRNA to trigger sequence-specific gene silencing. This is because studies have shown long dsRNAs trigger interferon response that could mask gene-specific RNAi effects. This thesis explored long dsRNA-mediated RNAi pathways in rainbow trout cells …

Delivery Of Small Molecule And Rna Using Synthetic Polymeric Micelles And Multifunctional Exosomes For The Treatment Of Type 1 Diabetes, Yang Peng

Theses & Dissertations

Type 1 diabetes is one of the most challenging chronic autoimmune diseases. The destruction and dysfunction of insulin-secreting β cells are the results of inflammatory infiltration and the synergistic effect of multiple immune cells. The aim of this dissertation is to develop novel and reliable therapeutic approaches to advance the treatment of T1D: including chemical modification of a broad-spectrum immunosuppressant, co-application of small molecule based immune intervention and siRNA based β cell preservative therapy, and administration of a PI3K-δ/γ dual inhibitor to specifically target immune cells, utilizing synthetic polymeric micelles or natural produced multi-functional exosomes derived from human bone marrow …

Genetic Analysis Of A Novel Ftsk Homolog, Hfka, In Streptomyces Coelicolor Development-Associated Chromosome Segregation, Sumedha Sethi

Electronic Theses and Dissertations

A quintessential phenomenon occurring during prokaryotic development is accurate segregation of the replicated genomes into the daughter cells. Key energy-dependent processes like chromosome condensation and subcellular partitioning of the genomes are driven by conserved proteins like SMC, ParB, FtsK. During its complex developmental cycle, Streptomyces coelicolor segregates its genomes into chains of unicellular spores when its multigenomic syncytial aerial hyphae undergo division.

A novel ftsK-like gene, hfkA (Homolog of FtsK protein A), was examined for function and localization during development-associated chromosome segregation. Individual deletions did not affect segregation, but a ΔhfkA ΔftsK mutant exhibited 8% anucleate …

Mechanism Of Bax/Bak Activation In Apoptotic Signaling, Kai Huang

Theses & Dissertations

The Bcl-2 family proteins, including the anti-apoptotic members, pro-apoptotic effectors Bax/Bak, and the BH3-only proteins, are key components of the mitochondrial apoptotic pathway. The BH3-only protein Bid is critical for the mitochondrial pathway of apoptosis after TRAIL-induced death receptor activation. However, the mechanism of Bid activation during TRAIL-induced apoptosis is unclear. By putting back wild-type and mutants of Bid in Bid deficient (Bid KO) and Bid/Bax/Bak TKO colon cancer cells, we demonstrated that cleavage by caspase 8 and mitochondrial targeting are critical events for Bid activation. One of the biggest mysteries in apoptosis is how Bax/Bak was activated by BH3-only …

Brca1 & Ctdp1 Brct Domainomics In The Dna Damage Response, Kimiko L. Krieger

Theses & Dissertations

Genomic instability is one of the enabling characteristics of cancer. DNA damage response pathways are important for genomic integrity and cell cycle progression. Defects in DNA damage repair can often lead to cell cycle arrest, cell death, or tumorigenesis. The activation of the DNA damage response includes tightly regulated signaling cascades that involve kinase phosphorylation and modular domains that scaffold phosphorylated motifs to coordinate recruitment of DNA repair proteins. Modular domains are conserved tertiary structures of a protein that can fold, function, and evolve independently from an intact protein. One of the most common modular domains involved in DNA damage …

Defining The Role Of Tyrosine Phosphorylation In The Regulation Of Connexin43 In Cardiac Diseases, Li Zheng

Theses & Dissertations

Connexins are integral membrane proteins that oligomerize to form gap junction channels. Ions and small molecules diffuse intercellularly through these channels, allowing individual cellular events to synchronize into the functional response of an entire organ. Gap junction channels composed of Connexin43 (Cx43) mediate electrical coupling and impulse propagation in the normal working myocardium. In the failing heart, Cx43 remodeling (decreased expression, altered phosphorylation state, loss at intercalated discs, and increased presence at lateral membranes) contributes to rhythm disturbances and contractile dysfunction. While there is considerable information regarding key interactions of Cx43 in the regulation of gap junction channels, unfortunately, the …

A "Choose-Your-Own" Classroom-Based Activity That Promotes Scientific Inquiry About Rna Interference, Jeremy L. Hsu

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

RNA interference (RNAi), the process that results in the degradation of a target gene’s mRNA, is a fundamental part of eukaryotic gene regulation and is also an important molecular technique that allows for experimental manipulation of gene expression without altering DNA sequences. Despite the importance of RNAi, there have been relatively few lecture-based activities designed to teach about the consequences of this process and counter common misconceptions. I present here an inquiry-based activity that is centered around a “choose your own experiment” design where students generate hypotheses and critically evaluate their ideas by choosing several simulated experiments. The activity presents …