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Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Mitochondrial Heteroplasmy Contributes To The Dynamic Atovaquone Resistance Response In Plasmodium Falciparum, Sasha Victoria Siegel Nov 2016

Mitochondrial Heteroplasmy Contributes To The Dynamic Atovaquone Resistance Response In Plasmodium Falciparum, Sasha Victoria Siegel

Graduate Theses and Dissertations

Of the considerable challenges researchers face in the control and elimination of malaria, the development of antimalarial drug resistance in parasite populations remains a significant hurdle to progress worldwide. Atovaquone is used in combination with proguanil (Malarone) as an antimalarial treatment in uncomplicated malaria, but is rendered ineffective by the rapid development of atovaquone resistance during treatment. Previous studies have established that de novo mutant parasites confer resistance to atovaquone with a substitution in amino acid 268 in the cytochrome b gene encoded by the parasite mitochondrial genome, yet much is still unknown about how this resistance develops, and whether ...


The Effects Of Phytohormones And Isoprenoids In Dihydroartemisinin-Induced Dormancy In The Erythrocytic Stages Of Plasmodium Falciparum, Marvin Duvalsaint Duvalsaint Nov 2016

The Effects Of Phytohormones And Isoprenoids In Dihydroartemisinin-Induced Dormancy In The Erythrocytic Stages Of Plasmodium Falciparum, Marvin Duvalsaint Duvalsaint

Graduate Theses and Dissertations

Our ability to control malaria has been challenged by increasing antimalarial resistance. Plasmodium falciparum undergoes dormancy in the blood stages which is hypothesized to be a means by which they are able to survive under drug pressure. This helps select for resistant parasites which grow following removal of drug. The mechanisms behind dormancy and the subsequent recrudescence are not fully understood but translating knowledge from related organisms which undergo a similar phenomenon might shed some light. Higher plants utilize dormancy during the early development stages to survive under unfavorable conditions, increasing fitness of the seedling and ensuring viability when this ...


Gene Expression Profiling And The Role Of Hsf1 In Ovarian Cancer In 3d Spheroid Models, Trillitye Paullin Nov 2016

Gene Expression Profiling And The Role Of Hsf1 In Ovarian Cancer In 3d Spheroid Models, Trillitye Paullin

Graduate Theses and Dissertations

Ovarian cancer is the most lethal gynecological cancer, with over 200,000 women diagnosed each year and over half of those cases leading to death. These poor statistics are related to a lack of early symptoms and inadequate screening techniques. This results in the cancer going undetected until later stages when the tumor has metastasized through a process that requires the epithelial to mesenchymal transition (EMT). In lieu of traditional monolayer cell culture, EMT and cancer progression in general is best characterized through the use of 3D spheroid models. In this study, we examine gene expression changes through microarray analysis ...


Significance Of Pten Phosphorylation And Its Nuclear Function In Lung Cancer, Prerna Malaney Nov 2016

Significance Of Pten Phosphorylation And Its Nuclear Function In Lung Cancer, Prerna Malaney

Graduate Theses and Dissertations

Phosphorylation mediated inactivation of PTEN leads to multiple malignancies with increased severity. However, the consequence of such inactivation on downstream functions of PTEN are poorly understood. Therefore, the objective of my thesis is to ascertain the molecular mechanisms by which PTEN phosphorylation drives lung cancer. PTEN phosphorylation at the C-terminal serine/threonine cluster abrogates its tumor suppressor function. Despite the critical role of the PTEN C-tail in regulating its function, the crystal structure of the C-tail remains unknown. Using bioinformatics and structural analysis, I determined that the PTEN C-tail is an intrinsically disordered region and is a hot spot for ...


Contribution Of Epithelial Hypoxia Signaling To Pulmonary Fibrosis: Role Of Fak1 And Galectin-1 As Driver Molecules, Jaymin J. Kathiriya Oct 2016

Contribution Of Epithelial Hypoxia Signaling To Pulmonary Fibrosis: Role Of Fak1 And Galectin-1 As Driver Molecules, Jaymin J. Kathiriya

Graduate Theses and Dissertations

Idiopathic Pulmonary Fibrosis (IPF) is a deadly disease of unknown origin, which causes 80,000 deaths every year in the US and Europe combined. Unknown etiology and late diagnosis, combined with limited treatment options, contribute to a dismal survival rate of 3-5 years post diagnosis. Although molecular mechanisms underlying IPF pathogenesis and progression have been studied for over two decades, lack of in vivo models that recapitulate chronic, progressive, and irreversible nature of IPF have contributed to limited therapeutic success in clinical trials. Currently, only two drugs, Pirfenidone and Nintedanib, are approved for IPF treatment in the US, with their ...


Cardiovascular Regulation By Kvβ1.1 Subunit, Jared Tur Oct 2016

Cardiovascular Regulation By Kvβ1.1 Subunit, Jared Tur

Graduate Theses and Dissertations

Heterologous expression systems such as COS-7 cells have demonstrated the profound effects of KCNAB1-3 or Kvβ1-3 proteins on voltage gated potassium channels (Kv) channels. Indeed, in the presence of these β-subunits transiently expressed Kv channels are often modulated in multiple ways. Kv channel membrane expression is often increased in the presence of β-subunits. In addition, non-inactivating Kv currents suddenly become fast-inactivating and fast-inactivating channels become even faster. While much research has demonstrated the profound effects the β-subunits in particular the Kvβ1 subunit have on transiently expressed Kv currents little to date is known of the physiological role it may play ...


Regulation Of Nachrs And Stemness By Nicotine And E-Cigarettes In Nsclc, Courtney Schaal Aug 2016

Regulation Of Nachrs And Stemness By Nicotine And E-Cigarettes In Nsclc, Courtney Schaal

Graduate Theses and Dissertations

Lung cancer is the leading cause of cancer-related death in both men and women, nationally and internationally and kills more people each year than breast, prostate, and colon cancers combined. Non-small cell lung carcinoma (NSCLC) is the most common histological subtype of lung cancer, and accounts for 85% of all cases. Cigarette smoking is the single greatest risk factor for lung cancer, and is correlated with 80-90% of all lung cancer deaths. Nicotine, the addictive component of tobacco smoke, is not a carcinogen and cannot initiate tumors itself; however, it is known to act as a tumor promoter, by enhancing ...


Computational Modeling Of Allosteric Stimulation Of Nipah Virus Host Binding Protein, Priyanka Dutta Jul 2016

Computational Modeling Of Allosteric Stimulation Of Nipah Virus Host Binding Protein, Priyanka Dutta

Graduate Theses and Dissertations

Nipah belongs to the family of paramyxoviruses that cause numerous fatal diseases in humans and farm animals. There are no FDA approved drugs for Nipah or any of the paramyxoviruses. Designing antiviral therapies that are more resistant to viral mutations require understanding of molecular details underlying infection. This dissertation focuses on obtaining molecular insights into the very first step of infection by Nipah. Such details, in fact, remain unknown for all paramyxoviruses. Infection begins with the allosteric stimulation of Nipah virus host binding protein by host cell receptors. Understanding molecular details of this stimulation process have been challenging mainly because ...


A Caenorhabditis Elegans Model To Detect Developmental Teratogens With Adverse Reproductive And Metabolic Effects, Alexis Ann Killeen Jul 2016

A Caenorhabditis Elegans Model To Detect Developmental Teratogens With Adverse Reproductive And Metabolic Effects, Alexis Ann Killeen

Graduate Theses and Dissertations

Obesity is a current epidemic in the United States. Greater than one third of adults and nearly one fifth of children are classified as obese (Ogden, 2014). Increased awareness of this problem has triggered interest into the potentially causal agents in our environment. These agents, termed obesogens, are a type of teratogen hypothesized to work during embryonic development by programming offspring to store excess fat. A type of teratogen, obesogens are also typically reprotoxic, affecting germline development and embryonic viability. These noxious teratogens span a variety of different chemical classes including estrogen mimics, metals and metalloids, biocides, and even voluntary ...


Cell Cycle Arrest By Tgfß1 Is Dependent On The Inhibition Of Cmg Helicase Assembly And Activation, Brook Samuel Nepon-Sixt Jun 2016

Cell Cycle Arrest By Tgfß1 Is Dependent On The Inhibition Of Cmg Helicase Assembly And Activation, Brook Samuel Nepon-Sixt

Graduate Theses and Dissertations

Tumorigenesis is a multifaceted set of events consisting of the deregulation of several cell-autonomous and tissue microenvironmental processes that ultimately leads to the acquisition of malignant disease. Transforming growth factor beta (TGFß) and its family members are regulatory cytokines that function to ensure proper organismal development and the maintenance of homeostasis by controlling cellular differentiation, proliferation, adhesion, and survival, as well as by modulating components of the cellular microenvironment and immune system. The pleiotropic control by TGFß of these cell intrinsic and extrinsic factors is intimately linked to the prevention of tumor formation, the specifics of which are dependent on ...


Intrinsic Disorder Where You Least Expect It: The Incidence And Functional Relevance Of Intrinsic Disorder In Enzymes And The Protein Data Bank, Shelly Deforte Jun 2016

Intrinsic Disorder Where You Least Expect It: The Incidence And Functional Relevance Of Intrinsic Disorder In Enzymes And The Protein Data Bank, Shelly Deforte

Graduate Theses and Dissertations

Intrinsically disordered proteins (IDPs) and intrinsically disordered protein regions (IDPRs) exist as interconverting conformational ensembles, without a single fixed three-dimensional structure in vivo. The focus in the literature up to this point has been primarily on IDPs that are mostly or entirely disordered. Therefore, we have an incomplete understanding of the incidence and functional relevance of IDPRs in proteins that have regions of both order and disorder. This work explores these populations, by examining IDPRs in the Protein Data Bank (PDB) and in enzymes. By applying disorder prediction methods combined with an analysis of missing regions in crystal structure data ...


Inhibiting The Interaction Between Grp94 And Myocilin To Treat Primary Open-Angle Glaucoma, Andrew Stothert Jun 2016

Inhibiting The Interaction Between Grp94 And Myocilin To Treat Primary Open-Angle Glaucoma, Andrew Stothert

Graduate Theses and Dissertations

Glaucoma is a neurodegenerative protein misfolding disorder classified by increases in IOP, damage to retinal ganglion cells (RGCs), optic nerve (ON) head damage, and progressive irreversible blindness. Primary open-angle glaucoma (POAG) is the most common form of glaucoma, constituting over 90% of clinical cases. POAG is observed in patients where normal outflow channels, mainly the trabecular meshwork (TM), are exposed at the angle formed by the iris and cornea. However, due to TM cellular dysfunction, aqueous outflow resistance is increased preventing normal circulation of aqueous humor. Recent studies have shown that in 2-4% of POAG cases, increased intracellular levels of ...


Cmg Helicase Assembly And Activation: Regulation By C-Myc Through Chromatin Decondensation And Novel Therapeutic Avenues For Cancer Treatment, Victoria Bryant Jun 2016

Cmg Helicase Assembly And Activation: Regulation By C-Myc Through Chromatin Decondensation And Novel Therapeutic Avenues For Cancer Treatment, Victoria Bryant

Graduate Theses and Dissertations

The CMG (Cdc45, MCM, GINS) helicase is required for cellular proliferation and functions to unwind double-stranded DNA to allow the replication machinery to duplicate the genome. Cancer cells mismanage helicase activation through a variety of mechanisms, leading to the potential for the development of novel anti-cancer treatments. Mammalian cells load an excess of MCM complexes that act as reserves for new replication origins to be created when replication forks stall due to stress conditions, such as drug treatment. Targeting the helicase through inhibition of the MCM complex has sensitized cancer cells to drugs that inhibit DNA replication, such as aphidicolin ...


Investigation Of Respiratory Syncytial Virus Structural Determinants And Exploitation Of The Host Ubiquitin System, Jillian Nicole Whelan Apr 2016

Investigation Of Respiratory Syncytial Virus Structural Determinants And Exploitation Of The Host Ubiquitin System, Jillian Nicole Whelan

Graduate Theses and Dissertations

Respiratory syncytial virus (RSV) is a globally circulating, non-segmented, negative sense (NNS) RNA virus that causes severe lower respiratory infections. This study explored several avenues to ultimately expand upon our understanding of RSV pathogenesis at the protein level. Evaluation of RSV intrinsic protein disorder increased the relatively limited description of the RSV structure-function relationship. Global proteomics analysis provided direction for further hypothesis-driven investigation of host pathways altered by RSV infection, specifically the interaction between the RSV NS2 protein and the host ubiquitin system. NS2 primarily acts to antagonize the innate immune system by targeting STAT2 for proteasomal degradation. The goal ...


Nonreplicative Dna Helicases Involved In Maintaining Genome Stability, Salahuddin Syed Apr 2016

Nonreplicative Dna Helicases Involved In Maintaining Genome Stability, Salahuddin Syed

Graduate Theses and Dissertations

Double-strand breaks and stalled forks arise when the replication machinery encounters damage from exogenous sources like DNA damaging agents or ionizing radiation, and require specific DNA helicases to resolve these structures. Sgs1 of Saccharomyces cerevisiae is a member of the RecQ family of DNA helicases and has a role in DNA repair and recombination. The RecQ family includes human genes BLM, WRN, RECQL4, RECQL1, and RECQL5. Mutations in BLM, WRN, and RECQL4 result in genetic disorders characterized by developmental abnormalities and a predisposition to cancer. All RecQ helicases have common features including a helicase domain, an RQC domain, and a ...


In Vitro And In Vivo Antioxidant Capacity Of Synthetic And Natural Polyphenolic Compounds Identified From Strawberry And Fruit Juices, Marvin Abountiolas Mar 2016

In Vitro And In Vivo Antioxidant Capacity Of Synthetic And Natural Polyphenolic Compounds Identified From Strawberry And Fruit Juices, Marvin Abountiolas

Graduate Theses and Dissertations

Strawberries can be considered a functional food because their consumption has been associated with several health benefits. They are important sources of bioactive compounds, such as vitamins and polyphenolic compounds, with recognized antioxidant capacity (AOC). However, strawberry overall quality and bioactive content are greatly affected by environmental conditions during pre- and post-harvest and, little is known about the stability of its bioactive compounds, specifically ascorbic acid (AA) and polyphenolics compounds. Furthermore, additional research that addresses the impact of polyphenolic compounds on in vitro and in vivo models is needed to understand the mechanisms behind their potential health benefits. Therefore, the ...


Global Regulator Of Virulence A (Grva) Coordinates Expression Of Discrete Pathogenic Mechanisms In Enterohemorrhagic Escherichia Coli Through Interactions With Gadw-Gade, Jason K. Morgan, Ronan K. Carroll, Carly M. Harro, Khoury W Vendura, Lindsey N. Shaw, James T. Riordan Feb 2016

Global Regulator Of Virulence A (Grva) Coordinates Expression Of Discrete Pathogenic Mechanisms In Enterohemorrhagic Escherichia Coli Through Interactions With Gadw-Gade, Jason K. Morgan, Ronan K. Carroll, Carly M. Harro, Khoury W Vendura, Lindsey N. Shaw, James T. Riordan

Cell Biology, Microbiology, and Molecular Biology Faculty Publications

UNLABELLED: Global regulator of virulence A (GrvA) is a ToxR-family transcriptional regulator that activates locus of enterocyte effacement (LEE)-dependent adherence in enterohemorrhagic Escherichia coli (EHEC). LEE activation by GrvA requires the Rcs phosphorelay response regulator RcsB and is sensitive to physiologically relevant concentrations of bicarbonate, a known stimulant of virulence systems in intestinal pathogens. This study determines the genomic scale of GrvA-dependent regulation and uncovers details of the molecular mechanism underlying GrvA-dependent regulation of pathogenic mechanisms in EHEC. In a grvA-null background of EHEC strain TW14359, RNA sequencing analysis revealed the altered expression of over 700 genes, including the ...


Measurement Of Elastic Modulus Of Collagen Type I Single Fiber, Pavel Dutov, Olga Antipova, Sameer Varma, Joseph P R O Orgel, Jay D Schieber Jan 2016

Measurement Of Elastic Modulus Of Collagen Type I Single Fiber, Pavel Dutov, Olga Antipova, Sameer Varma, Joseph P R O Orgel, Jay D Schieber

Cell Biology, Microbiology, and Molecular Biology Faculty Publications

Collagen fibers are the main components of the extra cellular matrix and the primary contributors to the mechanical properties of tissues. Here we report a novel approach to measure the longitudinal component of the elastic moduli of biological fibers under conditions close to those found in vivo and apply it to type I collagen from rat tail tendon. This approach combines optical tweezers, atomic force microscopy, and exploits Euler-Bernoulli elasticity theory for data analysis. This approach also avoids drying for measurements or visualization, since samples are freshly extracted. Importantly, strains are kept below 0.5%, which appear consistent with the ...


Mir494 Reduces Renal Cancer Cell Survival Coinciding With Increased Lipid Droplets And Mitochondrial Changes, Punashi Dutta, Edward Haller, Arielle Sharp, Meera Nanjundan Jan 2016

Mir494 Reduces Renal Cancer Cell Survival Coinciding With Increased Lipid Droplets And Mitochondrial Changes, Punashi Dutta, Edward Haller, Arielle Sharp, Meera Nanjundan

Cell Biology, Microbiology, and Molecular Biology Faculty Publications

Background: miRNAs can regulate cellular survival in various cancer cell types. Recent evidence implicates the formation of lipid droplets as a hallmark event during apoptotic cell death response. It is presently unknown whether MIR494, located at 14q32 which is deleted in renal cancers, reduces cell survival in renal cancer cells and if this process is accompanied by changes in the number of lipid droplets.

Methods: 769-P renal carcinoma cells were utilized for this study. Control or MIR494 mimic was expressed in these cells following which cell viability (via crystal violet) and apoptotic cell numbers (via Annexin V/PI staining) were ...


Direct Analysis In Real Time (Dart) Of An Organothiophosphate At Ultrahigh Resolution By Fourier Transform Ion Cyclotron Resonance Mass Spectrometry And Tandem Mass Spectrometry, Laszlo Prokai, Stanley M. Stevens Jr. Jan 2016

Direct Analysis In Real Time (Dart) Of An Organothiophosphate At Ultrahigh Resolution By Fourier Transform Ion Cyclotron Resonance Mass Spectrometry And Tandem Mass Spectrometry, Laszlo Prokai, Stanley M. Stevens Jr.

Cell Biology, Microbiology, and Molecular Biology Faculty Publications

Direct analysis in real time (DART) is a recently developed ambient ionization technique for mass spectrometry to enable rapid and sensitive analyses with little or no sample preparation. After swab-based field sampling, the organothiophosphate malathion was analyzed using DART-Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS) and tandem mass spectrometry (MS/MS). Mass resolution was documented to be over 800,000 in full-scan MS mode and over 1,000,000 for an MS/MS product ion produced by collision-induced dissociation of the protonated analyte. Mass measurement accuracy below 1 ppm was obtained for all DART-generated ions that belonged to ...


Effect Of Hydroxychloroquine And Characterization Of Autophagy In A Mouse Model Of Endometriosis, A. Ruiz, S. Rockfield, N. Taran, E. Haller, Robert Engelman, I Flores, P Panina-Bordignon, Meera Nanjundan Jan 2016

Effect Of Hydroxychloroquine And Characterization Of Autophagy In A Mouse Model Of Endometriosis, A. Ruiz, S. Rockfield, N. Taran, E. Haller, Robert Engelman, I Flores, P Panina-Bordignon, Meera Nanjundan

Cell Biology, Microbiology, and Molecular Biology Faculty Publications

In endometriosis, the increased survival potential of shed endometrial cells (which normally undergo anoikis) is suggested to promote lesion development. One mechanism that may alter anoikis is autophagy. Using an autophagic flux inhibitor hydroxychloroquine (HCQ), we identified that it reduces the in vitro survival capacity of human endometriotic and endometrial T-HESC cells. We also identified that HCQ could decrease lesion numbers and disrupt lesion histopathology, as well as increase the levels of peritoneal macrophages and the IP-10 (10 kDa interferon-γ-induced protein) chemokine in a mouse model of endometriosis. We noted that RNA levels of a subset of autophagic ...