Biochemistry, Biophysics, and Structural Biology Commons^™

Autophagy Plays An Essential Role In Mediating Regression Of Hypertrophy During Unloading Of The Heart, Nirmala Hariharan, Yoshiyuki Ikeda, Chull Hong, Ralph R. Alcendor, Soichiro Usui, Shumin Gao, Yasuhiro Maejima, Junichi Sadoshima

Publications and Research

Autophagy is a bulk degradation mechanism for cytosolic proteins and organelles. The heart undergoes hypertrophy in response to mechanical load but hypertrophy can regress upon unloading. We hypothesize that autophagy plays an important role in mediating regression of cardiac hypertrophy during unloading. Mice were subjected to transverse aortic constriction (TAC) for 1 week, after which the constriction was removed (DeTAC). Regression of cardiac hypertrophy was observed after DeTAC, as indicated by reduction of LVW/BW and cardiomyocyte cross-sectional area. Indicators of autophagy, including LC3-II expression, p62 degradation and GFP-LC3 dots/cell, were significantly increased after DeTAC, suggesting that autophagy is induced. Stimulation …

Analysis Of Small Molecule Ligands Targeting The Hiv-1 Matrix Protein-Rna Binding Site, Ayna Alfadhli, Henry Mcnett, Jacob Eccles, Seyram Tsagli, Colleen Noviello, Rachel Sloan, Claudia S. López, David H. Peyton, Eric Barklis

Chemistry Faculty Publications and Presentations

The matrix (MA) domain of the HIV-1 PrGag protein directs PrGag proteins to assembly sites at the plasma membrane by virtue of its affinity to the phospholipid, phosphatidylinositol-4,5-bisphosphate (PI(4,5)P₂). MA also binds to RNA at a site that overlaps its PI(4,5)P₂ site, suggesting that RNA binding may protect MA from associating with inappropriate cellular membranes prior to PrGag delivery to the PM. Based on this, we have developed an assay in which small molecule competitors to MA-RNA binding can be characterized, with the assumption that such compounds might interfere with essential MA functions and help elucidate additional features of MA …

Paper And Toner Three-Dimensional Fluidic Devices: Programming Fluid Flow To Improve Point-Of-Care Diagnostics, Kevin M. Schilling, Daisy Jauregui, Andres W. Martinez

Chemistry and Biochemistry

We present a new method for fabricating three-dimensional paper-based fluidic devices that uses toner as a thermal adhesive to bond multiple layers of patterned paper together. The fabrication process is rapid, involves minimal equipment (a laser printer and a laminator) and produces complex channel networks with dimensions down to 1 mm. The devices can run multiple diagnostic assays on one or more samples simultaneously, can incorporate positive and negative controls and can be programmed to display the results of the assays in a variety of patterns. The patterns of the results can encode information, which could be used to identify …

Cyclooxygenase-2 Dependent Metabolism Of 20-Hete Increases Adiposity And Adipocyte Enlargement In Mesenchymal Stem Cell-Derived Adipocytes, Dong Hyun Kim, Nitin Puri, Komal Sodhi, John R. Falck, Nader G. Abraham, Joseph I. Shapiro M.D., Michal L. Schwartzman

Biochemistry and Microbiology

Abstract 20-Hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE), a product of the cytochrome P450 (CYP)-catalyzed [1] -hydroxylation of arachidonic acid, induces oxidative stress and, in clinical studies, is associated with increased body mass index (BMI) and the metabolic syndrome. This study was designed to examine the effects of exogenous 20- HETE on mesenchymal stem cell (MSC)-derived adipocytes.

The expression levels of CYP4A11 and CYP4F2 (major 20-HETE synthases in humans) in MSCs decreased during adipocyte differentiation; however, exogenous administration of 20-HETE (0.1–1 M) increased adipogenesis in a dose dependent manner in these cells ( P < 0.05). The inability of a 20-HETE analog to reproduce these effects suggested the involvement of a metabolic product of 20-HETE in mediating its pro-adipogenic effects. A cyclooxygenase (COX)-1 selective inhibitor enhanced, whereas a COX-2 selective or a dual COX-1/2 inhibitor attenuated adipogenesis induced by 20-HETE. The COX-derived metabolite of 20-HETE, 20-OH-PGE 2 , enhanced adipogenesis and lipid accumulation in MSCs. The pro-adipogenic effects of 20-HETE and 20-OH-PGE 2 resulted in the increased expression of the adipogenic regulators PPAR and -catenin in MSC-derived adipocytes. Taken together we show for the fi rst time that 20-HETE-derived COX-2-dependent 20-OH-PGE 2 enhances mature infl amed adipocyte hypertrophy in MSC undergoing adipogenic differentiation. — Kim, D. H., N. Puri, K. Sodhi, J. R. Falck, N. G. Abraham, J. Shapiro, and M. L. Schwartzman. Cyclooxygenase-2 dependent metabolism of 20-HETE increasesadiposity and adipocyte enlargement in mesenchymal stem cell-derived adipocytes.

Single-Molecule Studies Of Local And Global Nucleic-Acid Dynamics, Eric Muthuri Patrick

Wayne State University Dissertations

Nucleic acids undergo both global and local conformational changes that are important for their function. Structural studies have over the decades been invaluable in elucidation of various biomolecular mechanisms, hence contributing significantly to the understanding of biological events. However, a clear understanding of how molecules function in the cellular context requires investigation of their interconversion between multiple conformations, including mapping the folding landscape and any coupled changes in conformation. Work in this thesis focuses on fluorescence experiments, mainly at a single-molecule level to investigate such processes.

First, a novel single-molecule approach is described focusing on local dynamics within nucleic acids …

Investigating Hfq-Mrna Interactions In Bacteria, Martha Audra Faner

Wayne State University Dissertations

Regulatory RNAs (sRNAs) are essential for bacteria to thrive in diverse environments and they also play a key role in virulence [11]. Trans-sRNAs affect the stability and/or translation of their target mRNAs through complementary base-pairing. The base-pairing interaction is not perfect and requires the action of an RNA binding protein, Hfq. Hfq facilitates these RNA-RNA interactions by stabilizing duplex formation, aiding in structural rearrangements, increasing the rate of structural opening, and/or by increasing the rate of annealing [18-21]. Hfq has two well characterized binding surfaces: the proximal surface, which binds AU rich stretches typical of sRNAs, and the distal surface, …

The Drosophila Interactions Database: Integrating The Interactome And Transcriptome, Thilakam Murali

Wayne State University Dissertations

In this thesis I describe the integration of heterogeneous interaction data for Drosophila into DroID, the Drosophilainteractions database, making it a one-stop public resource for interaction data. I have also made it possible to filter the interaction data using gene expression data to generate context-relevant networks making DroID a one-of-a kind resource for biologists. In the two years since the upgraded DroID has been available, several studies have used the heterogeneous interaction data in DroID to advance our understanding of Drosophila biology thus validating the need for such a resource for biologists. In addition to this, I have identified …

Roles Of Neuregulin1 In Neuromuscular Junction Development, Jiajing Wang

Wayne State University Dissertations

Neuromuscular junction (NMJ) development is a multistep process mediated by coordinated interactions between nerve terminals, target muscles, and peri-synaptic glial cells, and thus requires reciprocal signals derived from every cell type. Neuregulin1s (NRG1s) are a family of predominantly neuronal growth and differentiation factors that are important for many aspects of nervous system development. In this thesis, both the effects of NRG1 on NMJ development and reciprocal effects of neurotrophic factors on NRG1 expression were studied as a means to define the complex regulatory communication at the NMJ. Using the chicken embryo as a model, methods were developed to study the …

Cholera Toxin Activates The Unfolded Protein Response Through An Adenylate Cyclase-Independent Mechanism, Neyda Vanbennekom

Electronic Theses and Dissertations

Cholera toxin (CT) is a bacterial protein toxin responsible for the gastrointestinal disease known as cholera. CT stimulates its own entry into intestinal cells after binding to cell surface receptors. Once internalized, CT is delivered via vesicle-mediated transport to the endoplasmic reticulum (ER), where the CTA1 subunit dissociates from the rest of the toxin and is exported (or translocated) into the cytosol. CTA1 translocates from the ER lumen into the host cytosol by exploiting a host quality control mechanism called ER-associated degradation (ERAD) that facilitates the translocation of misfolded proteins into the cytosol for degradation. Cytosolic CTA1, however, escapes this …

Rescuing Acetylcholinesterase From Nerve Agent Inhibition: Protein Dynamics Driven Drug Discovery, Aiyana M. Emigh, Brian Bennion

STAR Program Research Presentations

Severe morbidity and mortality consequences result from irreversible inhibition of human acetylcholinesterase by organophosphates (OPs). Oxime-based reactivators are currently the only available treatments but lack efficacy in the central nervous system (CNS) where the most damage occurs. Computational docking and molecular dynamics (MD) simulations reveal complex structural barriers that may reduce oxime efficacy. These results may guide future drug designs of more effective countermeasures.

Genetic Regulation Of Mucoidy In Pseudomonas Aeruginosa, T. Ryan Withers

Theses, Dissertations and Capstones

Cystic fibrosis is a genetic disorder that results from mutations in the CF transmembrane conductance regulator gene. These mutations cause a disruption in the chloride transport in mucosal tissues causing the accumulation of dehydrated mucus, and a decrease in the mucocilliary removal of environmental pathogens within the lungs. Additionally, the accumulation of dehydrated mucus within the lungs provides a hospitable environment for various bacteria, including the Gram-negative opportunistic pathogen Pseudomonas aeruginosa. P. aeruginosa uses the overproduction of a surface polysaccharide called alginate to form a biofilm to evade the host’s immunological defenses. The overproduction of alginate, often referred to as …

Toward A Comprehensive Model Of Photosystem Ii Oxygen Evolving Complex Photoassembly, James Scott Board Ii

Theses, Dissertations and Capstones

Elucidating the mechanism of photoassembly of the oxygen-evolving complex (OEC) will lead to a better understanding of how nature catalyzes water oxidation. Although the temperature dependence of oxygen evolution has been described in the literature [1,2], we have performed a comprehensive study that covers Photosystem II (PSII) activity oxygen evolution in the presence and absence of 2,6-dichloro-1,4benzoquinone (DCBQ) from 5–45°C. In addition, we performed similar measurements for OEC photoassembly in the absence of DCBQ. PSIIenriched particles used for our measurements were prepared according to Berthold, Babcock, and Yocum[3], with modifications from Kolling, et al.[4] The oxygen-evolution of intact BBY particles …

Omega-3 Fatty Acids As Therapeutic Options For The Treatment Of B-Cell Chronic Lymphocytic Leukemia, Johannes Francois Fahrmann

Theses, Dissertations and Capstones

B-cell chronic lymphocytic leukemia (CLL) is the most common form of adult leukemia in the western world. CLL is often diagnosed in the asymptomatic (early-stage) stages. However, approximately 50% of these patients will progress to advanced, symptomatic disease and require therapy. Current treatment options are limited due to progressive drug resistance and severe drug-induced toxicities which are often too toxic for the elderly or those with co-morbidities. Therefore, a non-toxic therapeutic intervention that could slow the progression of asymptomatic CLL to symptomatic CLL or enhance the effects of actively used chemo-therapeutic drugs in patients who require therapy would be clinically …

A Comprehensive, Multi-Scale Dynamical Model Of Erbb Receptor Signal Transduction In Human Mammary Epithelial Cells, Tomas Helikar, Naomi Kochi, Bryan Kowal, Manjari Dimri, Mayumy Naramura, Srikumar M. Raja, Vimla Band, Hamid Band, Jim A. Rogers

Biochemistry and Molecular Medicine Faculty Publications

The non-receptor tyrosine kinase Src and receptor tyrosine kinase epidermal growth factor receptor (EGFR/ErbB1) have been established as collaborators in cellular signaling and their combined dysregulation plays key roles in human cancers, including breast cancer. In part due to the complexity of the biochemical network associated with the regulation of these proteins as well as their cellular functions, the role of Src in EGFR regulation remains unclear. Herein we present a new comprehensive, multi-scale dynamical model of ErbB receptor signal transduction in human mammary epithelial cells. This model, constructed manually from published biochemical literature, consists of 245 nodes representing proteins …

Novel Insights Into Breast Cancer Genetic Variance Through Rna Sequencing, Anelia Horvath, Suresh B. Pakala, Prakriti Mudvari, Sirigiri Divijendra Natha Reddy, Kazufumi Ohshiro, Sandra Casimiro, Ricardo Pires, Suzanne A.W. Fuqua, Masakazu Toi, Luis Costa, Sujit S. Nair, Saraswati Sukumar, Rakesh Kumar

Biochemistry and Molecular Medicine Faculty Publications

Using RNA sequencing of triple-negative breast cancer (TNBC), non-TBNC and HER2-positive breast cancer sub-types, here we report novel expressed variants, allelic prevalence and abundance, and coexpression with other variation, and splicing signatures. To reveal the most prevalent variant alleles, we overlaid our findings with cancer- and population-based datasets and validated a subset of novel variants of cancer-related genes: ESRP2, GBP1, TPP1, MAD2L1BP, GLUD2 and SLC30A8. As a proof-of-principle, we demonstrated that a rare substitution in the splicing coordinator ESRP2(R353Q) impairs its ability to bind to its substrate FGFR2 pre-mRNA. In addition, we describe novel SNPs and INDELs in …

Detection Of Viable Microorganisms Using Propidium Monoazide, Erik J. Mcfarland, Adrian Ponce Dr.

STAR Program Research Presentations

Propidium monoazide (PMA) is a molecular tool used to assess viability of microorganisms. Currently, PMA is thought to discern viability through membrane permeability; PMA enters only membrane compromised cells, irreversibly crosslinks to theirDNAand precipitates theDNAout of solution, preventing it from being amplified during polymerase chain reaction (PCR). Using PMA on a sample of live and dead microorganisms results in only theDNAof living organisms being amplified and identified. Therefore, a comparison ofPCRresults with and without PMA allows one to determine the live fraction and total population, respectively.

Current literature provides conflicting evidence as to the effectiveness of the technique. Our research …

Disocvering Ionic Liquid Resistant Genes, Bree Person, Douglass Higgins, Michael Thelen

STAR Program Research Presentations

: Plant biomass is a rich source of sugars that can be converted to biofuels by engineered microbes. However, because the lignocellulose in biomass is insoluble in aqueous conditions and recalcitrant to enzymatic degradation, thermochemical treatment is required to break apart the lignin and cellulose polymers before sugars can be released. The most effective chemicals for doing this are known as ionic liquids, which are salts that are molten at temperatures below 100° C. Although these solvents have many unique properties that are ideal for solubilizing lignocellulose, they have been found to inhibit the growth of bacterial strains used to …

Using Stable Isotope Analysis Of Zooplankton To Document Trophic And Biogeochemical Changes In The San Francisco Estuary, Steven C. Westbrook, Julien Moderan

STAR Program Research Presentations

Zooplankton represent a vital link between phytoplankton and fish, like the endangered Delta Smelt. Human interferences (nitrates from waste water, flow alteration, invasive species introduction…) have altered the structure of the San Francisco Estuary (SFE) ecosystem. We use stable isotope analysis to improve our knowledge of the planktonic food web in the SFE and gain insights into its evolution over the past decades. We use the ratios of certain isotopes (Nitrogen, Carbon, Sulfur, etc.) in different species of zooplankton to tell us what it is feeding on as well as the trophic level it feeds in. My research focused on …

Bone Morphogenetic Protein-7 Attenuates Inflammation And Apoptosis And Improves Cardiac Function In Diabetes, Princess Urbina

Electronic Theses and Dissertations

Bone Morphogenetic Protein-7 (BMP-7) belongs to the transforming growth factor-β (TGFβ) family of cytokines has is known to have potent anti-inflammatory properties. It has been used in patients to treat osteoporosis clinically and has been reported to treat diabetic nephropathy in murine models. Moreover, studies show that inflammation is up-regulated in patients with pre-diabetes (PD). We, therefore, hypothesize that the administration of BMP-7 will attenuate inflammation in the heart of Streptozotocin (STZ)-induced PD mice. In this study, we divided C57Bl/6 mice into three groups: CONTROL, PD, and PD+BMP-7. CONTROL mice received intraperitoneal (i.p.) injections of Sodium Citrate Buffer while PD …

Guilty Or Not Guilty: Can Dna Help Prove Guilt Or Innocence?, Suzanne Eckstein

The Science Journal of the Lander College of Arts and Sciences

Throughout our history, science was always on the front lines for discovery and exploration. Science is used as an investigative tool by the human race to figure out all the mysteries of the universe. The discovery of DNA was tremendous, providing each human being with their own unique genetic identity - no longer would an individual be genetically confused with another. DNA fingerprinting, in particular, has changed the world. In the 1980's the legal system began using DNA fingerprinting to help establish the guilt of an indicted criminal. DNA (besides for fingerprints) is the only way to confirm scientifically if …