Cell Biology Commons^™

Gβγ-Microtubule Interaction And Neurodegeneration, Jane K. Martinez, Jorge Sierra, Sukla Roychowdhury Ph.D.

COURI Symposium Abstracts, Summer 2012

Aberrant organization of microtubules (MTs) is known to be a feature of neurodegeneration, which occurs in many neurological disorder including Alzheimer’s disease, Parkinson’s disease, neuropsychiatric illness such as schizophrenia, and drug addiction. Previously, Gβγ, an important component of G protein-coupled signaling pathways, has been shown to regulate neurite outgrowth by interacting with MTs. The aim of the present study is to understand the Gβγ regulation of MT assembly and its relation to neurodegeneration, using GRK-ct peptide (consists of the carboxy terminus of G protein-coupled-receptor kinase) which is known to inhibit Gβγ-dependent signaling by binding to and sequestering Gβγ. PC12 cells …

Insights Into The Role Of The N-Terminus Of The Neuronal Glycine Transporter 2, Diego A. Escobar-Garcia, Ana Garibay, Miryam Pando, Manuel Miranda

COURI Symposium Abstracts, Summer 2012

Hyperekplexia is distinguished by exaggerated muscle tension, sudden shock and even death in response to touch/acoustic stimuli. Genetic analysis showed that mutations on glycinergic proteins on the presynaptic neurons are responsible for the attacks. Mutations in the Glycine Transporter 2 (GlyT2) have been suggested to be the second major cause of hyperekplexia. The GlyT2 consist of twelve transmembrane domains, a 201 amino acid long N-terminus and a shorter C-terminus, both intracellular. Dysfunction of this transporter prevents the intake of glycine from the synapse back to the presynaptic neuron. Our goal is to better understand the role of N-terminus on protein …

Identification Of Two Functional Sumo Interacting Motifs (Sims) In The Non-Structural Protein Of Influenza A Virus Ns1a, Lorellie M. Lewis, German Rosas-Acosta

COURI Symposium Abstracts, Summer 2012

We have previously shown that the non-structural protein of Influenza A virus NS1A is post-translationally modified by conjugation of the Small Ubiquitin-like MOdifier (SUMO). Our functional studies have also demonstrated that SUMO conjugation (SUMOylation) affects NS1A's ability to neutralize the cellular interferon response of the host cell and other functions associated to NS1A. Importantly, we have also shown that influenza infections trigger a global increase in cellular SUMOylation and have recently demonstrated that such an increase is mediated by NS1A. This observation led us to investigate the molecular mechanism endowing NS1A with the ability to increase global cellular SUMOylation. Sequence …

Delayed Expression Of Cell Cycle Proteins Contributes To Astroglial Scar Formation And Chronic Inflammation After Rat Spinal Cord Contusion, Junfang Wu, Ahdeah Pajoohesh-Ganji, Bogdan A. Stoica, Michael Dinizo, Kelsey Guanciale, Alan I. Faden

Anatomy and Regenerative Biology Faculty Publications

Background

Traumatic spinal cord injury (SCI) induces secondary tissue damage that is associated with astrogliosis and inflammation. We previously reported that acute upregulation of a cluster of cell-cycle-related genes contributes to post-mitotic cell death and secondary damage after SCI. However, it remains unclear whether cell cycle activation continues more chronically and contributes to more delayed glial change. Here we examined expression of cell cycle-related proteins up to 4 months following SCI, as well as the effects of the selective cyclin-dependent kinase (CDKs) inhibitor CR8, on astrogliosis and microglial activation in a rat SCI contusion model.

Methods

Adult male rats were …

The Human Phosphotyrosine Signaling Network: Evolution And Hotspots Of Hijacking In Cancer., Lei Li, Chabane Tibiche, Cong Fu, Tomonori Kaneko, Michael F. Moran, Martin Schiller, Shawn Shun-Cheng Li, Edwin Wang

Life Sciences Faculty Research

Phosphotyrosine (pTyr) signaling, which plays a central role in cell-cell and cell-environment interactions, has been considered to be an evolutionary innovation in multicellular metazoans. However, neither the emergence nor the evolution of the human pTyr signaling system is currently understood. Tyrosine kinase (TK) circuits, each of which consists of a TK writer, a kinase substrate, and a related reader, such as Src homology (SH) 2 domains and pTyr-binding (PTB) domains, comprise the core machinery of the pTyr signaling network. In this study, we analyzed the evolutionary trajectories of 583 literature-derived and 50,000 computationally predicted human TK circuits in 19 representative …

Dietary Analysis And Epigenetic Comparisons Of Drosphila Melanogaster Through Multiple Generations, Xu (Kevin) F. Zheng

Holster Scholar Projects

Nutrition and the lack thereof has been a demanding issue in both the undeveloped and developed country. The unbalance diet between healthy and unhealthy diet has led to many of the problems presented in society such as obesity, heart disorders, and loss of longevity. It is now known that calorie may not provide the most accurate information in terms of the lifestyle and the well-being of humans. Rather the composition of the calorie is what becomes integral in people's understanding of the effect of food physiologically. With this knowledge, we seek to use a Drosophila melanogaster as a model organism …

The Role Of Argininosuccinate Synthase Serine 328 Phosphorylation In Nitric Oxide Production, Ricci Haines

USF Tampa Graduate Theses and Dissertations

Until recently, the main mechanism of argininosuccinate synthase (AS) regulation was described to exist mainly at the level of transcription. Transcriptional regulation of AS has been shown to be coordinate with eNOS in response to shear stress, hypoxia, tumor necrosis factor á (TNF-á), and PPAR ã agonist troglitizone. However, it is now understood that one level of NO regulation is cellular control of arginine availability to eNOS via post-translational modifications of AS such as phosphorylation. The purpose of this investigation was to determine under what conditions AS is phosphorylated at S328, identify the pathway that AS phosphorylation at S328 plays …

Effects Of Ddt And Triclosan On Tumor-Cell Binding Capacity And Cell-Surface Protein Expression Of Human Natural Killer Cells, Tasia Hurd-Brown, Felicia Udoji, Tamara Martin, Margaret M. Whalen

Chemistry Faculty Research

1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) and triclosan (TCS) are organochlorine (OC) compounds that contaminate the environment, are found in human blood and have been shown to decrease the tumor-cell killing (lytic) function of human natural killer (NK) cells. NK cells defend against tumor cells and virally infected cells. They bind to these targets, utilizing a variety of cell surface proteins. The present study examined concentrations of DDT and TCS that decrease lytic function for alteration of NK binding to tumor targets. Levels of either compound that caused loss of binding function were then examined for effects on expression of cell-surface proteins needed for …

Host Pathogen Interactions: Is Arabidopsis Thaliana Remembered By Its Nemesis Pseudomonas Syringae?, Daniel Z. Kreiser

Lawrence University Honors Projects

Plants contain innate immune systems that deter pathogen infection. Pattern recognition receptors bind microbe-associated molecular patterns (MAMPs), triggering immunity. MAMPs are proteins exclusive to pathogens that are typically indispensable for their survival. For this reason, MAMPs cannot be mutated or removed without causing pathogen death. However, this does not necessitate constitutive expression of MAMPs. In this study, the MAMP response of Arabidopsis thaliana was utilized to determine differential detection of MAMPs expressed by Pseudomonas syringe pv. tomato DC3000 when pretreated with A. thaliana. Results demonstrated that more MAMPs are detected when P. syringae had previously encountered A. thaliana, …

Elucidating The Mechanism Of Antimigratory Activity Of Cardiac Glycosides, Joshua H. Johnson

Honors Scholar Theses

The focus of this research is on cell migration and how it can be better understood through the use of small molecules that modulate cell migratory activity. The results have particular relevance in the realm of cancer pharmacology. Cardiac glycosides, which are known inhibitors of the eukaryotic Na⁺/K⁺-ATPase, have been determined to have antimigratory activities through the screening of several small molecule libraries. Here we investigate the antimigratory activities of the cardiac glycoside digitoxin as well as its analogs that we synthesized. Antimigratory activity was determined by conducting a wound closure assay with MDA-MB-231 human breast …

Improvements To The Forensic Analysis Of Mitochondrial Dna Typing, Elizabeth Montano

Honors Scholar Theses

Sequence analysis of human mitochondrial DNA (mtDNA) is an effective and reliable tool for the genetic characterization of forensic samples. The nature of the mitochondrial genome (mtgenome), its high copy number and small size (~17kb) makes it more resistant to degradation and more stable than nuclear DNA. For this reason mitochondrial DNA is often the only feasible option for the forensic analysis of environmentally compromised samples. Currently the forensic analysis of the mtgenome is restricted to the hypervariable regions, also known as the Displacement loop (d-loop). Previous studies, confirmed in the Strausbaugh lab, have demonstrated an increased variability in the …

Metallothionein Gene Dose And The Immune Response, Meaghan Roy-O-Reilly

Honors Scholar Theses

Metallothionein (MT) is a small, cysteine-rich protein with significant immunomodulatory activity. It has been shown to play a critical role in important cellular mechanisms including heavy metal detoxification, essential metal management and the inflammatory response. MT production can be induced by a number of cellular stressors and acts to lessen the harmful effects of oxidizing agents and heavy metal exposure. Previous studies have shown that the dose of the metallothionein gene present in an individual may have significant effects on the adaptive immune response, yet the mechanism behind this phenomenon remains unknown. We hypothesize that the gene dose of metallothionein …

Identifying Progenitor Cells Of Heterotopic Ossification, Eileen E. Semancik

Honors Scholar Theses

Heterotopic Ossification (HO) is the abnormal formation of bone within extraskeletal soft tissues. The condition can occur through both genetic and acquired means. Acquired cases of HO result from invasive surgery or traumatic injuries, with increasing prevalence of ectopic skeletogenesis as a result of combat-related blast injuries. HO has been characterized to some extent, including the histological features and the mutation underlying the genetic form, but the cells resident in skeletal muscle that represent the progenitors of heterotopic bone have yet to be determined. Only a few publications have attempted to definitively determine the progenitor cells in this disorder. Findings …

Mutation And Complementation Of A Cellulose Synthase (Cesa) Gene, Ahmed Y. El-Araby

Senior Honors Projects

Cellulose is a carbohydrate polymer that is composed of repeating glucose subunits. Being the most abundant organic compound in the biosphere and comprising a large percentage of all plant biomass, cellulose is extremely plentiful and has a significant role in nature. Cellulose is present in plant cell walls, in commercial products such as those made from wood or cotton, and is of interest to the biofuel industry as a potential alternative fuel source. Although indigestible by humans, cellulose is nutritionally valuable, serving as a dietary fiber. Because of its ubiquity and importance in many areas, studying cellulose will prove to …

Environmental Friendly Synthesis, Characterization Of Surface Modifiable Starch Encapsulated Gold Nanoparticles With Bactericidal And Catalytic Activity, Dillon Pender

Mahurin Honors College Capstone Experience/Thesis Projects

In the present study, we report the green synthesis of gold nanoparticles (GNPs), using potato starch as a reducing as well as a stabilizing agent in an aqueous buffer medium. The resulting starch-GNPs (St-GNPs) were near spherical in shape with an average diameter of 15 ± 5 nm. In this approach, St-GNPs were characterized and investigated for their antibacterial properties against both gram negative (Escherichia coli) and gram positive (Staphylococcus epidermidis) bacteria. These St-GNPs were found to possess significant dose dependent antibacterial activity against bacteria. Also, St-GNPs showed a significant catalytic activity and can easily be …

Interaction Of Environmental B. Cenocepacia Strains With Cystic Fibrosis And Non-Cystic Fibrosis Bronchial Epithelial Cells In Vitro., Annamaria Bevivino, Luisa Pirone, Ruth Pilkington, Noemi Cifani, Claudia Dalmastri, Máire Callaghan, Fiorentina Ascenzioni, Siobhan Mcclean

Articles

Burkholderia cenocepacia is an important human pathogen in patients with cystic fibrosis (CF). Non-clinical reservoirs may play a role in the acquisition of infections, so it is important to evaluate the pathogenic potential of environmental B. cenocepacia isolates. In this study, we investigated the interactions of two environmental B. cenocepacia strains (Mex1 and MCII-168) with two bronchial epithelial cell lines,16HBE14o- and CFBE41o-, which have a non-CF and a CF phenotype, respectively.

The environmental strains showed a significantly lower level of invasion into both CF- and non-CF cells in comparison with the clinical B. cenocepacia LMG16656^T strain. Exposure of polarized …

Effect Of Combining Bcl-2 Inhibition And Radiation On Apoptotic Cell Death In Human Breast Cancer Cell Lines As Determined By Clonogenic Assay And Western Blots, Amari Sasha Howard

Renée Crown University Honors Thesis Projects - All

Cancer is a group of diseases characterized by abnormal control of cell growth and cell survival. Current treatment for cancer employs a combination of modalities including surgery, radiation, chemotherapeutic drugs, and immunotherapy. Our lab focuses on personalized medicine and treatments that can specifically target molecular features of a tumor as presented by the particular patient being treated. Cancers often exhibit an over-expression or under-expression of certain proteins that play a large role in regulating the process of apoptosis, which is programmed cell death. This study focuses on proposing drug treatment for cancer that is personalized in that it targets a …

Interactions Of Nitric Oxide And Superoxide Pathways In Hyperglycemic Endothelial Cells, Steven Clay Rogers

Graduate Theses and Dissertations

Cardiovascular complications arising from diabetic hyperglycemia represents one of the leading causes of death and greatest public health challenges of modern societies. Despite state-of-the-art glucose control, diabetic patients remain at a markedly increased risk of cardiovascular disease. The loss of endothelial function (the development of diabetic endothelial dysfunction) has been implicated in the development of numerous diabetic cardiovascular diseases. The endothelial cell produces many vasoactive substances, hormones and cytoprotective biological factors. Endothelial cells are also involved in and affected by the initiation of inflammatory responses through the release and interaction of cytokines and other immune system molecules. Therefore, regulation of …

Electrospun Polycaprolactone Nanofiber Scaffolds For Tissue Engineering, Andreas Haukas

Graduate Theses and Dissertations

Stem cell and tissue engineering offer us with a unique opportunity to research and develop new therapies for treating various diseases that are otherwise incurable using traditional medicines. However, development of these new therapies replies upon the establishment of in vitro cell culture and differentiation systems that mimic in vivo microenvironments required for cell-cell and cell-ECM interaction. The development of these cell culture systems depends upon the identification of appropriate biomaterials and cell sources. Biomaterials should be carefully selected and fabricated into scaffolds for supporting cell growth and differentiation. In this study, we explored the fabrication of 3D electrospun nanofiber …

Role Of Trp Channels In Mediating The Calcium Signaling Response Of Brain Endothelial Cells To Mechanical Stretch, Jonathan Berrout

Dissertations and Theses (Open Access)

Traumatic brain injury (TBI) often results in disruption of the blood brain barrier (BBB), which is an integral component to maintaining the central nervous system homeostasis. Recently cytosolic calcium levels ([Ca²⁺]i), observed to elevate following TBI, have been shown to influence endothelial barrier integrity. However, the mechanism by which TBI-induced calcium signaling alters the endothelial barrier remains unknown. In the present study, an in vitro BBB model was utilized to address this issue. Exposure of cells to biaxial mechanical stretch, in the range expected for TBI, resulted in a rapid cytosolic calcium increase. Modulation of intracellular and extracellular …