Digital Commons Network^™

The Role Of Gbf1 In Golgi Biogenesis And Secretory Traffic., Tomasz Szul

All ETDs from UAB

The secretory pathway within a cell consists of series of membrane compartments connected by shuttling secretory vesicles containing cargo that travel from endoplasmic reticulum (ER) though ER-to-Golgi intermediate compartment (ERGIC), the Golgi apparatus, and endosomal compartment to the plasma membrane (PM). The Golgi specific brefeldin A (BFA)-resistant factor 1 GBF1 has been identified as an important factor involved in traffic between ER and Golgi and within the Golgi apparatus. GBF1 belongs to a family of guanine nucleotide exchange factors (GEFs) that stimulate the exchange of GDP for GTP on small GTPases, ADP-ribosylation factors (ARFs). The exchange of the nucleotide activates …

Characterization Of The Induction And Regulation Of Early B Cell Development, Melissa Ann Thal

All ETDs from UAB

Hematopoiesis is a highly regulated process directed by the microenvironment or niche in the bone marrow and the transcription factors those signals activate. Gene knockout experiments have identified critical cytokine signals and transcription factors required for promoting the differentiation of a hematopoietic stem cell to a B cell, but the regulatory mechanisms have yet to be fully elucidated. In early B cell development, a transcriptional hierarchy exists wherein E2A proteins activate early B-cell factor (Ebf1), which in turn activates expression of the B cell commitment factor, Pax5. In our studies, we use IL-7 receptor alpha chain (IL-7Rα) knockout animals that …

Marginal Zone B-Cell Precursors As Cellular Agents For Type I Ifn Promoted Antigen Transport, John Hsien Wang

All ETDs from UAB

Type I IFN is a known pro-inflammatory cytokine that is associated with the development of systemic lupus erythematosus (SLE). At the level of B-cell regulation, current literature primarily attributes the formation of autoantibodies at the post-germinal center stage when type I IFN is known to promote plasmablast differentiation. However, our findings here point to a type I IFN effect at the pre-germinal stage. Type I IFN promotes T-dependent antibody response, activation-induced cytidine deaminase (AID) expression, germinal center formation, all of which are processes before the onset of plasmablast differentiation. We have determined a subset of splenic transitional B-cells, that is …

A Novel & Efficient Method To Produce High Titers Of Infectious Hpv In Organotypic Cultures Of Primary Human Keratinocytes, Hsu-Kun Wang

All ETDs from UAB

Infections by the high-risk human papillomavirus type 18 (HPV-18) or type 16 (HPV-16) can lead to cancers of the anogenital tract. Because the propagation of HPVs is restricted to differentiated human squamous epithelia, experimental studies of the productive program are conducted in organotypic cultures. The current methods are of low efficiency and time consuming and have relied on immortalized epithelial cell lines that do not support efficient viral DNA amplification or virion production, compromising HPV genetic analyses and obscuring normal virus-host cell interactions. I used Cre-loxP site-specific recombination to develop a relatively simple, fast and highly efficient system to produce …

Understanding The Regulatory Mechanisms Of Ubp-M And H2a Deubiquitination In Chromatin And Cellular Functions, Heui Yun Joo

All ETDs from UAB

Posttranslational modifications of histones regulate important chromatin and cellular functions. Among them, ubiquitination of histone H2A is correlated to transcriptional repression, such as HOX gene silencing and X chromosome inactiviation. Little was known about the removal of ubiquitin from histones, the enzyme(s) involved and its function in chromatin dynamics. We have identified the protein Ubp-M (USP16) to be the H2A- and nucleosome-specific deubiquitinase. We also demonstrated that Ubp-M-mediated H2A deubiquitination is involved in cell cycle progression to M-phase, HOX gene expression, and posterior development in Xenopus laevis. Furthermore, we have also purified USP12 and USP46 which contain an Ubp-M independent …

Regulation Of Vh Replacement In Human Immature B Cells By B Cell Receptor (Bcr) - Mediated Signaling, Jing Liu

All ETDs from UAB

VH replacement occurs through RAG-mediated secondary recombination to change unwanted IgH genes. In this dissertation, I focused on studying the molecular mechanism that regulates VH replacement in human immature B cells. In part I, our results show that VH replacement is regulated by B cell antigen receptor (BCR) mediated signaling. Using the human EU12 mHC+ cells as an experimental model system, crosslinking BCR with F(ab')2 anti-IgM antibodies results in BCR internalization, cell proliferation arrest, and induction of VH replacement. Pretreatment of human EU12 mHC+ cells with the protein tyrosine kinase inhibitor Genistein, Syk kinase inhibitors, and a Src kinase inhibitor …

Counterregulatory Roles Of Transforming Growth Factor (Tgf)-Beta And Atrial Natriuretic Peptide (Anp) In Pressure Overload-Induced Cardiac Remodeling And Fibrosis, Jason Anthony Lucas

All ETDs from UAB

Pressure overload stress (eg. hypertension or aortic stenosis) results in excessive cardiac fibrosis, changes in left ventricular (LV) geometry, and disruption of LV contractility, ultimately leading to heart failure. We hypothesize that transforming growth factor-beta (TGF-beta), a pro fibrogenic factor, and atrial natriuretic peptide (ANP), an anti fibrogenic factor, interact directly in a counterregulatory manner to balance the production of extracellular matrix (ECM) under pressure overload induced cardiac stress or hypoxia-induced pulmonary vascular adaptation. In this report, we examine structural and functional responses of the intact heart to pressure overload stress in vivo. We then utilize isolated rat pulmonary artery …

Mechanisms Of Growth Hormone Action In Skeletal Muscle, Mahendra Devaraj Mavalli

All ETDs from UAB

Growth hormone (GH) and insulin like growth factor-1 (IGF-1) exert profound growth promoting actions during pre and postnatal skeletal muscle development. GH and IGF-1 seem to promote their anabolic actions by influencing skeletal muscle cell prolif-eration and fusion. However, because GH stimulates the production of IGF-1 from the liver and other GH-responsive peripheral tissues, including skeletal muscle, the individual contributions of these two growth factors to anabolic responses in skeletal muscle remains poorly defined. In this dissertation research, I sought to distinguish the mechanisms responsible for growth hormone's (GH) anabolic actions in skeletal muscle. To accomplish this, I analyzed the …

Cystic Fibrosis Transmembrane Conductance Regulator (Cftr) Modulators And Their Mechanistic Basis: Relevance To Emerging Therapies For Cystic Fibrosis, Louise Clare Pyle

All ETDs from UAB

Cystic fibrosis (CF) is a lethal genetic disorder leading to pulmonary decline and premature death. The gene responsible for CF, the cystic fibrosis transmembrane conductance regulator (CFTR), serves as a chloride and bicarbonate channel situated at the apical cell surface of epithelia. The discovery of small molecules that augment channel gating of mutant CFTR (so-called `potentiators') represents a major theme of CF research, and offers hope for new therapeutic interventions. High-throughput screening (HTS) provides a means to test millions of agents in an unbiased manner for CFTR potentiating properties. New agents identified by HTS have undergone extensive pre-clinical and clinical …

The Role Of Mitochondria And Plasma Membrane Ca2+ Transport Systems In Ca2+-Dependent Glutamate Release From Rat Cortical Astrocytes, Reno Cervo Reyes

All ETDs from UAB

Astrocytes, a type of glial cell in the central nervous system, are recognized for their support roles to neurons. They supply neurons with metabolites, maintain ion homeostasis and clear the synaptic space of neurotransmitters. However, it has been found that some astrocytes have receptors for neurotransmitter and neuroligands, exhibit Ca2+ excitability when stimulated via these receptors, and secrete gliotransmitters as an output of this Ca2+ excitability. In the Ca2+-dependent release of glutamate, it has been shown that the endoplasmic reticulum is the predominant source and the extracellular space is the auxiliary source of free Ca2+ necessary for triggering exocytosis. Because …

Neuroinflammation And Fragile X Syndrome: Regulation By Glycogen Synthase Kinase-3, Christopher Joseph Yuskaitis

All ETDs from UAB

Neuroinflammation and Fragile X syndrome (FXS) are two particularly devastating neurologic conditions for which no adequate treatment exists and much is still unknown about the underlying cellular and molecular processes. Neuroinflammation contributes to the pathogenesis of many neurologic and psychiatric disorders, thus treatment of the underlying inflammation has broad implications. FXS is the most common cause of inherited intellectual and developmental delay and one of the few known genetic causes of autism. Neuroinflammation and FXS have potential links with glycogen synthase kinase-3 (GSK3) and its inhibitor, lithium. Therefore, the overall goal of this research was to examine the role of …

Diffusion Pathways Through The Outer Membrane Of Mycobacteria, Olga Danilchanka

All ETDs from UAB

The extraordinary capacity of Mycobacterium tuberculosis (Mtb) to adapt to environmental changes during infection contributes to its success as a pathogen. While the unique outer membrane (OM) of mycobacteria functions as a permeability barrier for toxic molecules, uptake of nutrients is required to sustain viability of Mtb. Whereas hydrophobic molecules can diffuse through membranes, uptake of small hydrophilic compounds is mediated by water-filled channels, porins. For example, Msp-like porins of M. smegmatis (Ms) were shown to be required for uptake of hydrophilic beta-lactam antibiotics, which are also known to diffuse through porins in gram-negative bacteria. Because the structure of the …

Mitochondrial Mislocalization Underlies Abeta42-Induced Neuronal Dysfunction In A Drosophila Model Of Alzheimer's Disease., Kanae Iijima-Ando, Stephen A Hearn, Christopher Shenton, Anthony Gatt, Lijuan Zhao, Koichi Iijima

Department of Biochemistry and Molecular Biology Faculty Papers

The amyloid-beta 42 (Abeta42) is thought to play a central role in the pathogenesis of Alzheimer's disease (AD). However, the molecular mechanisms by which Abeta42 induces neuronal dysfunction and degeneration remain elusive. Mitochondrial dysfunctions are implicated in AD brains. Whether mitochondrial dysfunctions are merely a consequence of AD pathology, or are early seminal events in AD pathogenesis remains to be determined. Here, we show that Abeta42 induces mitochondrial mislocalization, which contributes to Abeta42-induced neuronal dysfunction in a transgenic Drosophila model. In the Abeta42 fly brain, mitochondria were reduced in axons and dendrites, and accumulated in the somata without severe mitochondrial …

The Association Of Human Leukocyte Antigen(Hla) Alleles And Type 2 Diabetes Mellitus (T2dm) Among Mexican Americans (Ma), Kantibhai Motiram Patel

Open Access Theses & Dissertations

The epidemic of type 2 diabetes mellitus (T2DM) is ranked as a major public health priority across the United States and especially in the El Paso, Texas region. The risk for the development of T2DM is greater in minority groups, particularly among Mexican Americans (MA) who comprise approximately 78% of El Paso's population. The growing incidence of T2DM in this group is typically attributed to increase in weight (obesity). The incidence of diabetes may also be influenced by genetic factors that are unique to this group. Several earlier studies have identified genetic markers for type 1 diabetes mellitus (T1DM). These …

Development And Evaluation Of New Mask Protocols For Gene Expression Profiling In Humans And Chimpanzees, Donna M. Toleno, Gabriel Renaud, Tyra G. Wolfsberg, Munirul Islam, Derek E. Wildman, Kimberly D. Siegmund, Joseph G. Hacia

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Cross-species gene expression analyses using oligonucleotide microarrays designed to evaluate a single species can provide spurious results due to mismatches between the interrogated transcriptome and arrayed probes. Based on the most recent human and chimpanzee genome assemblies, we developed updated and accessible probe masking methods that allow human Affymetrix oligonucleotide microarrays to be used for robust genome-wide expression analyses in both species. In this process, only data from oligonucleotide probes predicted to have robust hybridization sensitivity and specificity for both transcriptomes are retained for analysis.

Results

To characterize the utility of this resource, we applied our mask protocols …

Faculty Publications 2008, Lsu Health Sciences Center New Orleans

Historical Faculty Publications

This Faculty bibliography contains 629 publications.

Role Of Mel-18 In Regulating Protein Sumoylation And Identification Of A New Polymorphism In Bmi-1, Jie Zhang

University of Kentucky Doctoral Dissertations

Small ubiquitin-like modifier (SUMO) regulates numerous biological functions. In a previous study we found that sumoylation of HSF2 is involved in regulating HSF2 bookmarking function, but the mechanism that mediates this regulation was unknown. The results in my work support the intriguing hypothesis that polycomb protein, Mel-18, actually functions as an anti-SUMO E3 protein, interacting both with HSF2 and the SUMO E2 Ubc9, but acting to inhibit Ubc9 activity and thereby decrease sumoylation of the HSF2.

This study also suggested that Mel-18 negatively regulates the sumoylation of other cellular proteins, and we extend its targets to RanGAP1 protein. The results …

Angiotensin Ii Induction Of Regional Effects In Murine Vasculature, Albert Phillip Owens Iii

University of Kentucky Doctoral Dissertations

The renin angiotensin system (RAS) exerts many diverse physiological functions throughout the body, mediated by its effector peptide, angiotensin II (AngII). AngII has been linked with a variety of different functions ranging from the initiation of severe vascular pathologies, such as atherosclerosis and abdominal aortic aneurysm (AAA), to mundane physiological processes of fluid homeostasis, vascular contraction, and regulation of blood pressure. To provide a potential link between these functions, an in-depth analysis of regional effects of AngII on aortic vasculature was performed.

The studies presented in this dissertation tested the overall hypothesis of whether regional changes exist in the vasculature …

Human Ribosomal Rna Gene Clusters Are Recombinational Hotspots In Cancer, Dawn Michelle Stults

University of Kentucky Master's Theses

The gene that produces the precursor RNA transcript to the three largest ribosomal RNA molecules (rDNA) is present in multiple copies and organized into gene clusters. They represent 0.5% of the diploid human genome but are critical for cellular viability. The individual genes possess very high levels of sequence identity and are present in high local concentration, making them ideal substrates for genomic rearrangement driven by dysregulated homologous recombination. Our laboratory has developed a sensitive physical assay capable of detecting recombination-mediated genomic restructuring in the rDNA by monitoring changes in lengths of the individual clusters. In order to determine whether …

Low Density Lipoprotein Receptor And Alzheimers Disease, Rangaraj K. Gopalraj

University of Kentucky Doctoral Dissertations

Since apoE allele status is the predominant Alzheimers disease (AD) genetic risk factor, functional single nucleotide polymorphisms (SNPs) in brain apoE receptors represent excellent candidates for association with AD. Therefore, three low density lipoprotein receptor (LDLR) SNPs were evaluated by TaqMan allelic discrimination assays for association with AD and I found that certain haplotypes alter the odds of AD. A SNP within LDLR exon 12, rs688, was identified in silico as neutralizing a putative exon splicing enhancer (ESE). Since LDLR is a major apoE receptor in the brain, I hypothesized that rs688 modulates LDLR splicing in neural tissues and associates …

Studies On The Role Of Acid Sphingomyelinase And Ceramide In The Regulation Of Tace Activity And Tnfα Secretion By Macrophages, Krasimira Rozenova

University of Kentucky Doctoral Dissertations

Acid Sphingomyelinase (ASMase) activity has been proposed to mediate LPS signaling in various cell types. This study shows that in macrophages, ASMase is a negative regulator of LPS-induced TNFα secretion. ASMasedeficient (asm^-/-) mice and isolated peritoneal macrophages produce several fold more TNFα than their wild-type (asm^+/+) counterparts when stimulated with LPS. The mechanism for these differences however is not transcriptional but post-translational.

The TNFα converting enzyme (TACE) catalyzes the maturation of the 26kD precursor (proTNFα) to the active 17kD form (sTNFα). In mouse peritoneal macrophages, the activity of TACE rather than the rate of TNFα mRNA …

The Interplay Between The Expression And Functions Of Wnt13 Isoforms During Apoptosis In Bovine Aortic Endothelial Cells, Tao Tang

University of Kentucky Doctoral Dissertations

Wnt proteins are crucial for development/homeostasis by controlling cell fate including apoptosis (Moon RT et al. 1997). Three humanWnt13 isoforms were identified: the secreted Wnt13A, mitochondrial Wnt13B, and nuclear Wnt13C forms; and nuclear Wnt13 had an increased sensitivity to LPS/TNF-induced apoptosis in primary endothelial cells (EC); both Wnt13B and C mRNA contain two start codons (AUG+1 and +74), but the same protein encoded from AUG+74 by Wnt13C was expressed lower than Wnt13B (Struewing IT et al.2006). We hypothesize that during EC apoptosis, the nuclear Wnt13C expression is regulated translationally; nuclear Wnt13 favors apoptosis through regulating the activity/expression of apoptosis-related factors; …

Roles Of Emx2 In Odorant Receptor Gene Expression And Olfactory Sensory Neuron Axon Growth, Jeremy Colin Mcintyre

University of Kentucky Doctoral Dissertations

The sense of smell relies upon the detection of odorants by neurons located in the nasal cavity. These neurons, referred to as olfactory sensory neurons (OSNs), line the olfactory epithelium and extend axons that make synaptic connections with mitral/tufted cells in the olfactory bulb. The mechanisms by which these synaptic connections form remain largely unknown. The development of these synaptic connections relies on the axons of immature OSNs innervating the olfactory bulb. The primary goal of this dissertation was to identify components of the mechanisms used by immature OSN axons to innervate the olfactory bulb. To accomplish this goal, a …

Role Of Aryl Hydrocarbon Receptor In Chronic Inflammatory Diseases, Violeta Arsenescu

University of Kentucky Doctoral Dissertations

Aryl Hydrocarbon Receptor (AhR) is a ligand-actviated receptor known as the dioxin receptor. Environmental pollutants called dioxin-like toxicants are found in food, cigarette smoke, automobile exhaust and air. Therefore, they could chronically amplify the pathology of numerous chronic inflammatory diseases. AhR is a well known target of these environmental chemicals that disrupt endocrine signaling. By the year 2020, the number of people older than 60 years is expected to top 1 billion. The burden of treating chronic disease is significant both in dollars spent and in lost productivity. The need to identify risk factors for chronic diseases must be evaluated …

Regulation Of Low Density Lipoprotein Receptor Splicing Efficiency, I-Fang Ling

University of Kentucky Doctoral Dissertations

Low density lipoprotein receptor (LDLR) is an apolipoprotein E (apoE) receptor and may play a role in Alzheimer’s disease (AD) development. A single nucleotide polymorphism (SNP), rs688, that has been identified to modulate the splicing efficiency of LDLR exon 12 and is associated with higher cholesterol and AD in some case-control populations. The exon 12 deleted mRNA is predicted to produce a soluble form of LDLR that fails to mediate apoE uptake. To gain additional insights, in this study, I seek to understand the regulation of LDLR splicing efficiency. To identify functional cis-elements within LDLR exon 12, I mutated several …

Adenovirus E4orf4 Induces Hpv-16 Late L1 Mrna Production, Monica Somberg, Margaret Rush, Joanna Fay, Fergus Ryan, Helen Lambkin, Göran Akusjärvi, Stefan Schwartz

Articles

The adenovirus E4orf4 protein regulates the switch from early to late gene expression during the adenoviral replication cycle. Here we report that overexpression of adenovirus E4orf4 induces human papillomavirus type 16 (HPV-16) late gene expression from subgenomic expression plasmids. E4orf4 specifically overcomes the negative effects of two splicing silencers at the two late HPV-16 splice sites SD3632 and SA5639. This results in the production of HPV-16 spliced L1 mRNAs. We show that the interaction of E4orf4 with protein phosphatase 2A (PP2A) is necessary for induction of HPV-16 late gene expression. Also an E4orf4 mutant that fails to bind the cellular …

The Interaction Of Hab18g/Cd147 With Integrin Alpha6beta1 And Its Implications For The Invasion Potential Of Human Hepatoma Cells., Jing-Yao Dai, Ke-Feng Dou, Cong-Hua Wang, Pu Zhao, Wayne Bond Lau, Ling Tao, Ya-Mei Wu, Juan Tang, Jian-Li Jiang, Zhi-Nan Chen

Department of Emergency Medicine Faculty Papers

BACKGROUND: HAb18G/CD147 plays pivotal roles in invasion by hepatoma cells, but the underlying mechanism remains unclear. Our previous study demonstrated that overexpression of HAb18G/CD147 promotes invasion by interacting with integrin alpha3beta1. However, it has never been investigated whether alpha3beta1 is solely responsible for this process or if other integrin family members also interact with HAb18G/CD147 in human hepatoma cells. METHODS: Human SMMC-7721 and FHCC98 cells were cultured and transfected with siRNA fragments against HAb18G/CD147. The expression levels of HAb18G/CD147 and integrin alpha6beta1 were determined by immunofluorescent double-staining and confocal imaging analysis. Co-immunoprecipitation and Western blot analyses were performed to examine …

Repression Of E-Cadherin By The Polycomb Group Protein Ezh2 In Pancreatic Cancer, A. D. Toll, A. Dasgupta, M. Potoczek, C. G. Kleer, J. R. Brody, A. K. Witkiewicz

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Our study suggest that E-cadherin downregulation may lead to EZH20-mediated invasion and metastasis. While strong diffuse EZH2 expression is seen in PDA, overexpression may be present in IPMN.

Identification Of Gastrointestinal Contamination In Pancreatic Fna, A. D. Toll, M. Bibbo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

In contrast to previous work, our preliminary results indicate B72.3 expression cannot be reliably used to identify GIC. A lack of CEA expression, however, may be used to identify both gastric and duodenal contamination. This represents an important diagnostic aid in the evaluation of suspected low-grade mucinous lesions.

Revealing Genes Associated With Vitellogenesis In The Liver Of The Zebrafish (Danio Rerio) By Transcriptome Profiling., Liraz Levi, Irena Pekarski, Ellen Gutman, Paolo Fortina, Terry Hyslop, Jakob Biran, Berta Levavi-Sivan, Esther Lubzens

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: In oviparous vertebrates, including fish, vitellogenesis consists of highly regulated pathways involving 17beta-estradiol (E2). Previous studies focused on a relatively small number of hepatic expressed genes during vitellogenesis. This study aims to identify hepatic genes involved in vitellogenesis and regulated by E2, by using zebrafish microarray gene expression profiling, and to provide information on functional distinctive genes expressed in the liver of a vitellogenic female, using zebrafish as a model fish. RESULTS: Genes associated with vitellogenesis were revealed by the following paired t-tests (SAM) comparisons: a) two-month old vitellogenic (Vit2) females were compared with non-vitellogenic (NV) females, showing 825 …