Life Sciences Commons^™

Investigations In Enhancing The Reproducibility Of Implantable Amperometric Glucose Biosensors For Mass Production, Dipesh Manharbhai Patel

Honors Scholar Theses

Implantable glucose sensors for Diabetes management should possess several attributes such as linearity, sensitivity, selectivity, long life time and should elicit no negative tissue response. Based on this, the UConn implantable glucose sensor team has developed a 5-layer sensor architecture that simultaneously affords the aforementioned requirements. However, the large scale production of these 5-layer sensors is inhibited by the lack of high sensor-to-sensor reproducibility. Herein, we investigate the origin of sensor-to-sensor irreproducibility and develop methodologies for large-scale fabrication of these devices.

Effects Of Arsenic Responsive P21 On Innate Immunity And Apoptosis In Zebrafish, Gabriel O. Vachon

Honors College

Arsenic is a heavy metal that is frequently found in drinking water, especially well-water in the Northeastern United States. Arsenic is thought to be involved with numerous negative health conditions. This project examined the impact of this environmental toxicant, on the zebrafish innate immune system. Specifically, this project characterized the gene encoding for the protein p21. The particular gene is cdkn1a (will be referred to here by its product "p21" both for the protein and gene itself which will be italicized) and had increased expression as a result of arsenic exposure from a previously complete microarray analysis. In attempt to …

Characterizing The Role Of Cortactin In Actin Pedestal Assembly By Enterohemorrhagic Escherichia Coli (Ehec), Sarah E. Grout

Honors Scholar Theses

Enterohemorrhagic Escherichia coli (EHEC) is a major foodborne cause of bloody diarrhea and renal failure. During colonization of the intestine, EHEC injects the transmembrane receptor protein Tir and the cytoplasmic effector protein EspFU into host cells to reorganize the actin cytoskeleton into adhesion “pedestals.” EspFU has been shown to bind and activate the actin nucleation factor N-WASP to drive actin polymerization into pedestals. However, EspFU can still assemble pedestals in cells lacking N-WASP, suggesting that this effector protein is able to also trigger N-WASP-independent pathways of actin polymerization during infection. Cortactin is an atypical nucleation factor that localizes to pedestals, …

Evolutionary And Molecular Analysis Of Conserved Vertebrate Immunity To Fungi, Erin Carter

Honors College

The innate immune system is highly conserved amongst all multicellular organisms. Yet a constant battle exists between host cells and pathogens due to the rapid evolution of immune system components. Functional genomics and in silico methods can be employed to elucidate the evolutionary patterns of vertebrate immunity to pathogenic fungi such as Candida albicans, an opportunistic fungal pathogen that can cause lethal candidiasis in the immunocompromised. Mammals such as humans and mice possess conserved C-type lectin receptors that recognize the C. albicans cell wall. However, these receptors have not been identified in fish. Here I describe how we identified potential …

The Use Of Genomic “Knock-In” Strategy To Examine The Role Of The Protein Acyl Transferase (Dhhc) Family Of Enzymes Using Dictyostelium Discoideum, Joshua Little

Honors College

Palmitoylation is a reversible, post translational, lipid modification performed by proteinacyltransferases (PAT). PATs are membrane-bound enzymes which contain a conserved region that is rich in cysteine residues and contains a DHHC (Asp-His-His-Cys) conserved domain. This region is involved in the transfer of a 16-carbon palmitate from palmitoyl-CoA to a target protein. Palmitoylation plays many important functions such as targeting the protein to a lipid raft, shuttling the target protein or anchoring it to the cell membranes as well as aiding in the three dimensional folding of the protein. This process plays an important role in signal transduction, anchoring and cellular …

A Novel Mechanism For Mechanosensing By Endothelial Cells, Jennifer Macdowell

Honors College

The formation of new vasculature is an essential process, but can also be utilized by cancerous cells. Angiogenesis requires the directed migration of the endothelial cells lining the nascent blood vessels. This process is largely mediated by integrin, which plays a key role in the interplay between sensing a force in the extracellular matrix (ECM) and transducing this signal, a process termed mechanotransduction. Through cell-ECM focal adhesions, integrin mediates the signaling both into and out of the cell, promoting growth of focal adhesions and subsequent cell spreading and migration. In order to study focal adhesion dynamics related to force, we …

Nuclear Localization Of Cpi-17, A Protein Phosphatase-1 Inhibitor Protein, Affects Histone H3 Phosphorylation And Corresponds To Proliferation Of Cancer And Smooth Muscle Cells., Masumi Eto, Jason A Kirkbride, Rishika Chugh, Nana Kofi Karikari, Jee In Kim

Department of Molecular Physiology and Biophysics Faculty Papers

CPI-17 (C-kinase-activated protein phosphatase-1 (PP1) inhibitor, 17kDa) is a cytoplasmic protein predominantly expressed in mature smooth muscle (SM) that regulates the myosin-associated PP1 holoenzyme (MLCP). Here, we show CPI-17 expression in proliferating cells, such as pancreatic cancer and hyperplastic SM cells. Immunofluorescence showed that CPI-17 was concentrated in nuclei of human pancreatic cancer (Panc1) cells. Nuclear accumulation of CPI-17 was also detected in the proliferating vascular SM cell culture and cells at neointima of rat vascular injury model. The N-terminal 21-residue tail domain of CPI-17 was necessary for the nuclear localization. Phospho-mimetic Asp-substitution of CPI-17 at Ser12 attenuated the nuclear …

Intrinsic Apoptotic Pathway: Effects Of Calcium On Murine Cytochrome C Release In Brain And Liver Mitochondria, Dane M. Edwards

Senior Honors Theses

A cell may use one of three main apoptotic pathways leading to programmed cell death: the extrinsic pathway, the perforin/granzyme pathway and the intrinsic pathway. The most pertinent to this discussion is the intrinsic pathway, which utilizes the mitochondria as an essential intermediary. Mitochondria’s primary function in relation to this pathway is the subsequent release of pro-apoptotic factors including cytochrome c, which activate a caspase cascade leading to the death of the cell. Cytochrome c is released partly due to an increase in cytosolic calcium levels. Two methods of the release of cytochrome c have been proposed. The first is …

A Myosin-Va Tail Fragment Sequesters Dynein Light Chains Leading To Apoptosis In Melanoma Cells, Tc Izidoro-Toledo, Ac Borges, Dd Araujo, Dps Leitao Mazzi, Fo Nascimento Junior, Jf Sousa, Cp Alves, Apb Paiva, Dm Trindade, Ev Patussi, Pablo M. Peixoto, Kw Kinnally, Em Espreafico

Publications and Research

Previous studies proposed that myosin-Va regulates apoptosis by sequestering pro-apoptotic Bmf to the actin cytoskeleton through dynein light chain-2 (DLC2). Adhesion loss or other cytoskeletal perturbations would unleash Bmf, allowing it to bind and inhibit pro-survival Bcl2 proteins. Here, we demonstrated that over expression of a myosin-Va medial tail fragment (MVaf) harboring the binding site for DLC2 dramatically decreased melanoma cell viability. Morphological and molecular changes, including surface blebbing, mitochondrial outer membrane permeabilization, cytochrome-c and Smac release, as well as caspase-9/-3 activation and DNA fragmentation indicated that melanoma cells died of apoptosis. Immobilized MVaf interacted directly with DLCs, but complexed …

Immobile Myosin-Ii Plays A Scaffolding Role During Cytokinesis In Budding Yeast, C. Wloka, Elizabeth Ann Vallen, Lydia Thé , '08, X. Fang, Y. Oh, E. Bi

Biology Faculty Works

Core components of cytokinesis are conserved from yeast to human, but how these components are assembled into a robust machine that drives cytokinesis remains poorly understood. In this paper, we show by fluorescence recovery after photobleaching analysis that Myo1, the sole myosin-II in budding yeast, was mobile at the division site before anaphase and became immobilized shortly before cytokinesis. This immobility was independent of actin filaments or the motor domain of Myo1 but required a small region in the Myo1 tail that is thought to be involved in higher-order assembly. As expected, proteins involved in actin ring assembly (tropomyosin and …

Long-Term Data For Endemic Frog Genera Reveal Potential Conservation Crisis In The Bale Mountains, Ethiopia, David J. Gower, Roman K. Aberra, Silvia Schwaller, Malcolm J. Largen, Ben Collen, Stephen Spawls, Michele Menegon, Breda M. Zimkus, Rafael O. De Sá, Et Al.

Biology Faculty Publications

Populations of many frogs have declined alarmingly in recent years, placing nearly one third of the > 6,000 species under threat of extinction. Declines have been attributed largely to habitat loss, environmental degradation and/or infectious diseases such as chytridiomycosis. Many frogs undergo dramatic natural population fluctuations such that long-term data are required to determine population trends without undue influence of stochastic factors. We present long-term quantitative data (individuals encountered per person hour of searching) for four monotypic frog genera endemic to an Afromontane region of exceptional importance but growing conservation concern: one endemic to the Ethiopian highlands (Spinophrynoides osgoodi) and three …

Differential Transcriptional Regulation Of Meis1 By Gfi1b And Its Co-Factors Lsd1 And Corest, Asif H. Chowdhury, Johnny R. Ramroop, Ghanshyam Upadhyay, Ananya Sengupta, Anna Andrzejczyk, Shireen Saleque

Publications and Research

Gfi1b (growth factor independence 1b) is a zinc finger transcription factor essential for development of the erythroid and megakaryocytic lineages. To elucidate the mechanism underlying Gfi1b function, potential downstream transcriptional targets were identified by chromatin immunoprecipitation and expression profiling approaches. The combination of these approaches revealed the oncogene meis1, which encodes a homeobox protein, as a direct and prominent target of Gfi1b. Examination of the meis1 promoter sequence revealed multiple Gfi1/1b consensus binding motifs. Distinct regions of the promoter were occupied by Gfi1b and its cofactors LSD1 and CoREST/Rcor1, in erythroid cells but not in the closely related megakaryocyte lineage. …

Characterizing The Heavy Metal Chelator, Tpen, As A Ca2+ Tool In The Mammalian Oocyte, Robert A. Agreda Mccaughin

Masters Theses 1911 - February 2014

N,N,N’,N’-tetrakis-(2-Pyridylmethyl) ethylenediamine (TPEN) is a heavy metal chelator with high affinity for zinc. TPEN causes important responses in mammalian eggs. For example, these eggs are arrested at the MII stage by the Endogenous Mitotic Inhibitor 2 (Emi2), which prevents activation of the Anaphase Promoting Complex (APC) and degradation of Cyclin B. By chelating zinc, TPEN inactivates Emi2 and eggs undergo spontaneous exit of meiosis and egg activation. TPEN chelates Ca²⁺ with lower affinity, although in the Endoplasmic Reticulum (ER), where Ca²⁺ concentrations are high, TPEN may sequester Ca²⁺ preventing release into the cytoplasm. Initial exposure of TPEN …

Stiffness And Modulus And Independent Controllers Of Breast Cancer Metastasis, Dannielle Ryman

Masters Theses 1911 - February 2014

One out of eight women in the United States will develop breast cancer during their lifetime. Ninety percent of cancer related deaths are due to metastasis. Metastasis is the biological process where individual or aggregate cancerous cells break away from the primary tumor site and colonize distant, non-adjacent locations throughout the body. It is my objectives to study how mechanical, topographical and biochemical cues affect metastatic breast cancer metastasis at an early developmental stage. ECM components have previously been shown to affect cell motility via ligand-receptor interactions, and physical cues, such as matrix stiffness and protein density. The primary tumor …

Examining The Functional Role Of Dprl-1 In Drosophila Melanogaster, John Valenzuela

Summer Research

The Phosphatase of Regenerating Liver (PRL) family of proteins control cell growth, motility and proliferation. They have been shown to elevate the levels of these functions, leading to an increase in cancer metastasis (“malignancy”), when they are overexpressed. The goal of this experiment is to knockout PRL gene expression to examine the general function of PRL proteins. Drosophila melanogaster have only one copy of the PRL gene (dPRL-1), as opposed to humans and other mammals, which have 3. Thus, using P-element imprecise excision to create mutant strains either fully lacking or with decreased function of the dPRL-1 protein, …

Comparison Of Th1 Cytokines And T Cell Markers Gene Expressions Between Virulent And An Attenuated Eiav Vaccine Strain, Talia R. Henkle

Lewis Honors College Capstone Collection

The equine infectious anemia virus (EIAV) is closely related to HIV and has been used as a model to identify protective mechanisms against lentivirus infection. In horses, EIA infection progresses for about a year before infected horses manage to control virus replication. This naturally-gained protection is absolutely dependent on active immune responses as evidenced by the fact that immunosuppressive drugs can induce the recurrence of disease. As the resolution of initial viremia correlates with the appearance of virus specific cytotoxic T lymphocytes (CTL), we believe that cellular immune responses play a key role in controlling EIAV in the horse. In …

A Path To Success? A Review Of Evolution, Development, And The Predictable Genome By David L. Stern, Hope Hollocher, Charles H. Pence, Grant Ramsey, Michelle M. Wirth

Faculty Publications

No abstract provided.

The Dn2 Myeloid-T (Dn2mt) Progenitor Is A Target Cell For Leukemic Transformation By The Tlx1 Oncogene, Lynnsey A. Zweier-Renn, Irene Riz, Teresa S. Hawley, Robert G. Hawley

Anatomy and Regenerative Biology Faculty Publications

Introduction: Inappropriate activation of the TLX1 (T-cell leukemia homeobox 1) gene by chromosomal translocation is a recurrent event in human T-cell Acute Lymphoblastic Leukemia (T-ALL). Ectopic expression of TLX1 in murine bone marrow progenitor cells using a conventional retroviral vector efficiently yields immortalized cell lines and induces T-ALL-like tumors in mice after long latency.

Methods: To eliminate a potential contribution of retroviral insertional mutagenesis to TLX1 immortalizing and transforming function, we incorporated the TLX1 gene into an insulated self-inactivating retroviral vector.

Results: Retrovirally transduced TLX1-expressing murine bone marrow progenitor cells had a growth/survival advantage and readily gave rise to immortalized …

Alloreactivity-Based Medical Conditions, Stanislav Vukmanovic, Margaret G. Petroff, Anne M. Stevens, Daniel Rukavina

Pediatrics Faculty Publications

No abstract provided.

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 …

Extracellular Proteases Are Key Mediators Of Staphylococcus Aureus Virulence Via The Global Modulation Of Virulence-Determinant Stability, Stacey L. Kolar, J. Antonio Ibarra, Frances E. Rivera, Joe M. Mootz, Jessica E. Davenport, Stanley M. Stevens Jr., Alexander R. Horswill, Lindsey N. Shaw

Molecular Biosciences Faculty Publications

Staphylococcus aureus is a highly virulent and successful pathogen that causes a diverse array of diseases. Recently, an increase of severe infections in healthy subjects has been observed, caused by community-associated methicillin-resistant S. aureus (CA-MRSA). The reason for enhanced CA-MRSA virulence is unclear; however, work suggests that it results from hypersecretion of agr-regulated toxins, including secreted proteases. In this study, we explore the contribution of exo-proteases to CA-MRSA pathogenesis using a mutant lacking all 10 enzymes. We show that they are required for growth in peptide-rich environments, serum, in the presence of antimicrobial peptides (AMPs), and in human blood. …

Late Developing Mammary Tumors And Hyperplasia Induced By A Low-Oncogenic Variant Of Mouse Mammary Tumor Virus (Mmtv) Express Genes Identical To Those Induced By Canonical Mmtv, Robert D. Bruno

School of Medical Diagnostics & Translational Sciences Faculty Publications

Background: The canonical milk-transmitted mouse mammary tumor virus (MMTV) of C3H mice (C3H-MMTV) rapidly induces tumors in 90% of infected animals by 8 months of age. Pro-viral insertions of C3H-MMTV into genomic DNA results in the overexpression of common core insertion site (CIS) genes, including Wnt1/10b, Rspo2, and Fgf3. Conversely, infection by either the endogenous Mtv-1 virus (in C3Hf) or the exogenous nodule-inducing virus (NIV) (in Balb/c NIV) induces premalignant mammary lesions and tumors with reduced incidence and longer latency than C3H-MMTV. Here, we asked whether Mtv-1/NIV affected the expression of core CIS genes.

Findings: We confirmed the presence of …

Hydraphiles: A Rigorously Studied Class Of Synthetic Channel Compounds With In Vivo Activity, Saeedeh Negin, Bryan Smith, Alexandra Unger, W. Leevy, George Gokel

Chemistry & Biochemistry Faculty Works

No abstract provided.

The Bio-Nano-Interface In Predicting Nanoparticle Fate And Behaviour In Living Organisms: Towards Grouping And Categorising Nanomaterials And Ensuring Nanosafety By Design, Hugh Byrne, Arti Ahluwalia, Diana Boraschi,, Bengt Fadeel, Peter Gehr, Arno C. Gutleb, Michaela Kendall, Manthos Papadopoulos, Iseult Lynch

Articles

In biological media, nanoparticles acquire a coating of biomolecules (proteins, lipids, polysaccharides) from their surroundings, which reduces their surface energy and confers a biological identity to the particles. This adsorbed layer is the interface between the nanomaterial and living systems and therefore plays a significant role in determining the fate and behaviour of the nanoparticles. This review summarises the state of the art in terms of understanding the bio-nano interface and provides direction for potential future research directions and some recommendations for future priorities and strategies to support the safe implementation of nanotechnologies. The central premise is that nanomaterials must …

Identification Of Proteins At Active, Stalled, And Collapsed Replication Forks Using Isolation Of Proteins On Nascent Dna (Ipond) Coupled With Mass Spectrometry, Bianca M. Sirbu, W. Hayes Mcdonald, Huzefa Dungrawala, Akosua Badu-Nkansah, Gina M. Kavanaugh, Yaoyi Chen, David L. Tabb, David Cortez

Molecular Biosciences Faculty Publications

Both DNA and chromatin need to be duplicated during each cell division cycle. Replication happens in the context of defects in the DNA template and other forms of replication stress that present challenges to both genetic and epigenetic inheritance. The replication machinery is highly regulated by replication stress responses to accomplish this goal. To identify important replication and stress response proteins, we combined isolation of proteins on nascent DNA (iPOND) with quantitative mass spectrometry. We identified 290 proteins enriched on newly replicated DNA at active, stalled, and collapsed replication forks. Approximately 16% of these proteins are known replication or DNA …

Evaluation Of Antibiotic Resistance Emerging From Use Of Antibiotics In Cafos, J. R. Robbins, D. Hellman, N. Pease, M. Costello

Faculty Scholarship

No abstract provided.

Menthol Binding And Inhibition Of A7-Nicotinic Acetylcholine Receptors, Abrar Ashoor, Jacob C. Nordman, Daniel Veltri, Keun-Hang Susan Yang, Lina T. Al Kury, Yaroslav M. Shuba, Mohamed Magoub, Frank Christopher Howarth, Bassem Sadek, Amarda Shehu, Nadine Kabbani, Murat Oz

Mathematics, Physics, and Computer Science Faculty Articles and Research

Menthol is a common compound in pharmaceutical and commercial products and a popular additive to cigarettes. The molecular targets of menthol remain poorly defined. In this study we show an effect of menthol on the α7 subunit of the nicotinic acetylcholine (nACh) receptor function. Using a two-electrode voltage-clamp technique, menthol was found to reversibly inhibit α7-nACh receptors heterologously expressed in Xenopus oocytes. Inhibition by menthol was not dependent on the membrane potential and did not involve endogenous Ca2+-dependent Cl− channels, since menthol inhibition remained unchanged by intracellular injection of the Ca2+ chelator BAPTA and perfusion with Ca2+-free bathing solution containing …

Differential Modulation Of Functional Dynamics And Allosteric Interactions In The Hsp90-Cochaperone Complexes With P23 And Aha1: A Computational Study, Kristin Blacklock, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Allosteric interactions of the molecular chaperone Hsp90 with a large cohort of cochaperones and client proteins allow for molecular communication and event coupling in signal transduction networks. The integration of cochaperones into the Hsp90 system is driven by the regulatory mechanisms that modulate the progression of the ATPase cycle and control the recruitment of the Hsp90 clientele. In this work, we report the results of computational modeling of allosteric regulation in the Hsp90 complexes with the cochaperones p23 and Aha1. By integrating protein docking, biophysical simulations, modeling of allosteric communications, protein structure network analysis and the energy landscape theory we …

A Transient Α-Helical Molecular Recognition Element In The Disordered N-Terminus Of The Sgs1 Helicase Is Critical For Chromosome Stability And Binding Of Top3/Rmi1, Jessica A. Kennedy, Gary W. Daughdrill, Kristina H. Schmidt

Molecular Biosciences Faculty Publications

The RecQ-like DNA helicase family is essential for the maintenance of genome stability in all organisms. Sgs1, a member of this family in Saccharomyces cerevisiae, regulates early and late steps of double-strand break repair by homologous recombination. Using nuclear magnetic resonance spectroscopy, we show that the N-terminal 125 residues of Sgs1 are disordered and contain a transient α-helix that extends from residue 25 to 38. Based on the residue-specific knowledge of transient secondary structure, we designed proline mutations to disrupt this α-helix and observed hypersensitivity to DNA damaging agents and increased frequency of genome rearrangements. In vitro binding assays …

Phenotypic And Genotypic Characterization Of Escherichia Coli Isolated From Untreated Surface Waters, Kai F. Hung, Steven L. Daniel, Kristopher J. Janezic, Blake Ferry, Eric W. Hendricks, Brian A. Janiga, Tiffany Johnson, Samantha Murphy, Morgan E. Roberts, Sarah M. Scott, Alexandra N. Theisen

Faculty Research & Creative Activity

A common member of the intestinal microbiota in humans and animals is Escherichia coli. Based on the presence of virulence factors, E. coli can be potentially pathogenic. The focus of this study was to isolate E. coli from untreated surface waters (37 sites) in Illinois and Missouri and determine phenotypic and genotypic diversity among isolates. Water samples positive for fecal coliforms based on the Colisure® test were streaked directly onto Eosin Methylene Blue (EMB) agar (37°C) or transferred to EC broth (44.5°C). EC broth cultures producing gas were then streaked onto EMB agar. Forty-five isolates were identified as E. coli …