Life Sciences Commons^™

Puerto Rican Karst - A Vital Resource, Ariel E. Lugo, Leopoldo Miranda Castro, Abel Vale, Tania Del Mar López, Enrique Hernández Prieto, Andrés García Martinó, Alberto R. Puente Rolón, Adrianne G. Tossas, Donald A. Mcfarlane, Tom Miller, Armando Rodríguez, Joyce Lundberg, John Thomlinson, José Colón, Johannes H. Schellekens, Olga Ramos, Eileen Helmer

WM Keck Science Faculty Papers

The limestone region of Puerto Rico covers about 27.5 percent of the island's surface and is subdivided into the northern, southern, and dispersed limestone areas. All limestone areas have karst features. The karst belt is that part of the northern limestone with the most spectacular surficial karst landforms. It covers 142,544 ha or 65 percent of the northern limestone. The karst belt is the focus of this publication, although reference is made to all limestone regions. The northern limestone contains Puerto Rico's most extensive freshwater aquifer, largest continuous expanse of mature forest, and largest coastal wetland, estuary, and underground cave …

The Toxoplasma Gondii Protein Rop2 Mediates Host Organelle Association With The Parasitophorous Vacuole Membrane, Anthony P. Sinai, Keith A. Joiner

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Toxoplasma gondii replicates within a specialized vacuole surrounded by the parasitophorous vacuole membrane (PVM). The PVM forms intimate interactions with host mitochondria and endoplasmic reticulum (ER) in a process termed PVM–organelle association. In this study we identify a likely mediator of this process, the parasite protein ROP2. ROP2, which is localized to the PVM, is secreted from anterior organelles termed rhoptries during parasite invasion into host cells. The NH₂-terminal domain of ROP2 (ROP2hc) within the PVM is exposed to the host cell cytosol, and has characteristics of a mitochondrial targeting signal. In in vitro assays, ROP2hc is …

Marek's Disease Virus (Mdv) Encodes An Interleukin-8 Homolog (Vil-8): Characterization Of The Vil-8 Protein And A Vil-8 Deletion Mutant Mdv, Mark S. Parcells, Su-Fang Lin, Robert L. Dienglewicz, Vladimir Majerciak, Dan R. Robinson, Hua-Chien Chen, Zining Wu, George R. Dubyak, Peter Brunovskis, Henry D. Hunt

Dartmouth Scholarship

Chemokines induce chemotaxis, cell migration, and inflammatory responses. We report the identification of an interleukin-8 (IL-8) homolog, termed vIL-8, encoded within the genome of Marek's disease virus (MDV). The 134-amino-acid vIL-8 shares closest homology to mammalian and avian IL-8, molecules representing the prototype CXC chemokine. The gene for vIL-8 consists of three exons which map to the BamHI-L fragment within the repeats flanking the unique long region of the MDV genome. A 0.7-kb transcript encoding vIL-8 was detected in an n-butyrate-treated, MDV-transformed T-lymphoblastoid cell line, MSB-1. This induction is essentially abolished by cycloheximide and herpesvirus DNA polymerase inhibitor phosphonoacetate, indicating …

The Mannose-Sensitive Hemagglutinin Of Vibrio Cholerae Promotes Adherence To Zooplankton, Deborah A. Chiavelli, Jane W. Marsh, Ronald K. Taylor

Dartmouth Scholarship

The bacterium Vibrio cholerae, the etiological agent of cholera, is often found attached to plankton, a property that is thought to contribute to its environmental persistence in aquatic habitats. The V. cholerae O1 El Tor biotype and V. cholerae O139 strains produce a surface pilus termed the mannose-sensitive hemagglutinin (MSHA), whereas V. cholerae O1 classical biotype strains do not. Although V. cholerae O1 classical does not elaborate MSHA, the gene is present and expressed at a level comparable to that of the other strains. Since V. cholerae O1 El Tor and V. cholerae O139 have displaced V. cholerae O1 classical …

Cakß/Pyk2 Kinase Is A Signaling Link For Induction Of Long-Term Potentiation In Ca1 Hippocampus, Yueqiao Huang, Wei-Yang Lu, Declan W. Ali, Kenneth A. Pelkey, Graham M. Pitcher, You Ming Lu, Hiroshi Aoto, John C. Roder, Terukatsu Sasaki, Michael W. Salter

PCOM Scholarly Works

Long-term potentiation (LTP) is an activity-dependent enhancement of synaptic efficacy, considered a model of learning and memory. The biochemical cascade producing LTP requires activation of Src, which upregulates the function of NMDA receptors (NMDARs), but how Src becomes activated is unknown. Here, we show that the focal adhesion kinase CAKß/Pyk2 upregulated NMDAR function by activating Src in CA1 hippocampal neurons. Induction of LTP was prevented by blocking CAKß/Pyk2, and administering CAKß/Pyk2 intracellularly mimicked and occluded LTP. Tyrosine phosphorylation of CAKß/Pyk2 and its association with Src was increased by stimulation that produced LTP. Finally, CAKß/Pyk2-stimulated enhancement of synaptic AMPA responses was …

Impaired Fast-Spiking, Suppressed Cortical Inhibition, And Increased Susceptibility To Seizures In Mice Lacking Kv3.2 K+ Channel Proteins, David Lau, Eleazar Vega-Saenz De Miera, Diego Contreras, Alan Chow, Richard Paylor, Christopher S. Leonard, Bernardo Rudy

NYMC Faculty Publications

Voltage-gated K(+) channels of the Kv3 subfamily have unusual electrophysiological properties, including activation at very depolarized voltages (positive to -10 mV) and very fast deactivation rates, suggesting special roles in neuronal excitability. In the brain, Kv3 channels are prominently expressed in select neuronal populations, which include fast-spiking (FS) GABAergic interneurons of the neocortex, hippocampus, and caudate, as well as other high-frequency firing neurons. Although evidence points to a key role in high-frequency firing, a definitive understanding of the function of these channels has been hampered by a lack of selective pharmacological tools. We therefore generated mouse lines in which one …

Ryanodine Receptor Adaptation, Michael Fill, A. Zahradníková, Carlos A. Villalba-Galea, I. Zahradník, A. L. Escobar, S. Györke

School of Pharmacy Faculty Articles

In the heart, depolarization during the action potential activates voltage-dependent Ca²⁺ channels that mediate a small, localized Ca²⁺ influx (I_Ca). This small Ca²⁺ signal activates specialized Ca²⁺ release channels, the ryanodine receptors (RyRs), in the sarcoplasmic reticulum (SR). This process is called Ca²⁺-induced Ca²⁺ release (CICR). Intuitively, the CICR process should be self-regenerating because the Ca²⁺ released from the SR should feedback and activate further SR Ca²⁺ release. However, the CICR process is precisely controlled in the heart and, consequently, some sort of negative control mechanism(s) must exist to …

The Toxicology Of Aluminum In The Brain: A Review, Robert A. Yokel

Pharmaceutical Sciences Faculty Publications

Aluminum is environmentally ubiquitous, providing human exposure. Usual human exposure is primarily dietary. The potential for significant Al absorption from the nasal cavity and direct distribution into the brain should be further investigated. Decreased renal function increases human risk of Al-induced accumulation and toxicity. Brain Al entry from blood may involve transferrin-receptor mediated endocytosis and a more rapid process transporting small molecular weight Al species. There appears to be Al efflux from the brain, probably as Al citrate. There is prolonged retention of a fraction of Al that enters the brain, suggesting the potential for accumulation with repeated exposure. Al …

Prolonged Cyclooxygenase-2 Induction In Neurons And Glia Following Traumatic Brain Injury In The Rat, Kenneth I. Strauss, Mary F. Barbe, Renee Marshall Demarest, Ramesh Raghupathi, Samir Mehta, Raj K. Narayan

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Cyclooxygenase-2 (COX2) is a primary inflammatory mediator that converts arachidonic acid into precursors of vasoactive prostaglandins, producing reactive oxygen species in the process. Under normal conditions COX2 is not detectable, except at low abundance in the brain. This study demonstrates a distinctive pattern of COX2 increases in the brain over time following traumatic brain injury (TBI). Quantitative lysate ribonuclease protection assays indicate acute and sustained increases in COX2 mRNA in two rat models of TBI. In the lateral fluid percussion model, COX2 mRNA is significantly elevated (>twofold, p < 0.05, Dunnett) at 1 day postinjury in the injured cortex and bilaterally in the hippocampus, compared to sham-injured controls. In the lateral cortical impact model (LCI), COX2 mRNA peaks around 6 h postinjury in the ipsilateral cerebral cortex (fivefold induction, p < 0.05, Dunnett) and in the ipsilateral and contralateral hippocampus (two- and six-fold induction, respectively, p < 0.05, Dunnett). Increases are sustained out to 3 days postinjury in the injured cortex in both models. Further analyses use the LCI model to evaluate COX2 induction. Immunoblot analyses confirm increased levels of COX2 protein in the cortex and hippocampus. Profound increases in COX2 protein are observed in the cortex at 1-3 days, that return to sham levels by 7 days postinjury (p < 0.05, Dunnett). The cellular pattern of COX2 induction following TBI has been characterized using immunohistochemistry. COX2-immunoreactivity (-ir) rises acutely (cell numbers and intensity) and remains elevated for several days following TBI. Increases in COX2-ir colocalize with neurons (MAP2-ir) and glia (GFAP-ir). Increases in COX2-ir are observed in cerebral cortex and hippocampus, ipsilateral and contralateral to injury as early as 2 h postinjury. Neurons in the ipsilateral parietal, perirhinal and piriform cortex become intensely COX2-ir from 2 h to at least 3 days postinjury. In agreement with the mRNA and immunoblot results, COX2-ir appears greatest in the contralateral hippocampus. Hippocampal COX2-ir progresses from the pyramidal cell layer of the CA1 and CA2 region at 2 h, to the CA3 pyramidal cells and dentate polymorphic and granule cell layers by 24 h postinjury. These increases are distinct from those observed following inflammatory challenge, and correspond to brain areas previously identified with the neurological and cognitive deficits associated with TBI. While COX2 induction following TBI may result in selective beneficial responses, chronic COX2 production may contribute to free radical mediated cellular damage, vascular dysfunction, and alterations in cellular metabolism. These may cause secondary injuries to the brain that promote neuropathology and worsen behavioral outcome.

The Age Of The Woolly Rhino From Dream Cave, Derbyshire, Uk, Donald A. Mcfarlane, Joyce Lundberg, Derek C. Ford

WM Keck Science Faculty Papers

The Dream Cave woolly rhinoceros, Coelodonta antiquitatis, is a "classic" specimen of a "cold-stage" fossil fauna from central England. The find was illustrated and described by Dean William Buckland in his seminal tome Reliquiae Diluvianae (1823) during the first half of the 19th century, and made a significant contribution to the development of Buckland's views on the origin of extinct and extirpated fossil vertebrates. The report presents the first, albeit indirect, radiometric dates on the specimen, and argues that the animal fell into the cave just before 37,000 years BP, during the middle of Marine Isotope Stage 3 Interstadial (41 …

Introducing Animals To New Foods, Behave

All Current Publications

This publication explains different ways of successfully introducing animals to new foods.

Why Animals Die From Eating Poisonous Plants, Usu Extension

All Current Publications

If animals can learn which plants are toxic and which are safe, then why do they eat poisonous plants and die?

Response Of The Tick Dermacentor Variabilis (Acari: Ixodidae) To Hemocoelic Inoculation Of Borrelia Burgdorferi (Spirochetales), Robert Johns, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

When Borrelia burgdorferi B31 low passage strain spirochetes were directly injected into the hemocoel of Dermacentor variabilis(Say) females, the bacteria were cleared from the hemocoel within < 24 h. Viable spirochetes were not found in hemolymph, salivary gland, or ovary tissues by subculturing or by IFA. The hemocyte population increased ≈6 times within the first 6 h after inoculation compared with the uninoculated controls. In contrast, the soluble total hemolymph protein content decreased inversely with the increase in hemocytes. Borreliacidal activity was demonstrated with cell-free hemolymph from D. variabilis. In vitro antimicrobial assays using hemolymph from borrelia-challenged and nonchallenged ticks resulted in 72% spirochete reductions compared with only 11.5%, respectively, within 1 h. Additional evidence of induced antimicrobial hemolymph protein activity was demonstrated by SDS-PAGE, which revealed upregulation of a lysozyme-like peptide (≈ 15 kDa) (22% increase) and the induction of a ≈ 5.8 kDa peptide in the B. burgdorferi-challenged ticks. In contrast with the nonvector borne Bacillus subtilis …

Late Quaternary Fossil Mammals And Last Occurrence Dates From Caves At Barahona, Puerto Rico, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Puerto Rico supported at least five genera of endemic terrestrial mammals in the late Quaternary, all of which are extinct. Whether these animals died out in the late Pleistocene, the mid-Holocene, or in post-Columbian time has not been established. This paper is the first attempt at radiometrically dating the 'last occurrences' of these taxa, together with the first unambiguous descriptions of localities reported by previous workers. Last occurrence dates for Nesophontes, Elasmodontomys and Heteropsomys are shown to be mid-Holocene and overlap with Amerindian occupation of the island. Acratocnus is known only from the late Pleistocene. No Puerto Rican taxon has …

A Pdz-Interacting Domain In Cftr Is An Apical Membrane Polarization Signal, Bryan D. Moyer, Jerod Denton, Katherine H. Karlson, Donna Reynolds, Shusheng Wang, John E. Mickle, Michael Milewski, Garry R. Cutting, William B. Guggino, Min Li, Bruce A. Stanton

Dartmouth Scholarship

Polarization of the cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated chloride channel, to the apical plasma membrane of epithelial cells is critical for vectorial transport of chloride in a variety of epithelia, including the airway, pancreas, intestine, and kidney. However, the motifs that localize CFTR to the apical membrane are unknown. We report that the last 3 amino acids in the COOH-terminus of CFTR (T-R-L) comprise a PDZ-interacting domain that is required for the polarization of CFTR to the apical plasma membrane in human airway and kidney epithelial cells. In addition, the CFTR mutant, S1455X, which lacks the 26 …

Dynactin Is Required For Microtubule Anchoring At Centrosomes, N J. Quintyne, S. R. Gill, D M. Eckley, C L. Crego, D A. Compton, T A. Schroer

Dartmouth Scholarship

The multiprotein complex, dynactin, is an integral part of the cytoplasmic dynein motor and is required for dynein-based motility in vitro and in vivo. In living cells, perturbation of the dynein–dynactin interaction profoundly blocks mitotic spindle assembly, and inhibition or depletion of dynein or dynactin from meiotic or mitotic cell extracts prevents microtubules from focusing into spindles. In interphase cells, perturbation of the dynein–dynactin complex is correlated with an inhibition of ER-to-Golgi movement and reorganization of the Golgi apparatus and the endosome–lysosome system, but the effects on microtubule organization have not previously been defined. To explore this question, we overexpressed …

A Defect In Interleukin 12-Induced Activation And Interferon Gamma Secretion Of Peripheral Natural Killer T Cells In Nonobese Diabetic Mice Suggests New Pathogenic Mechanisms For Insulin-Dependent Diabetes Mellitus., Marika Falcone, Brian Yeung, Lee Tucker, Enrique Rodriguez, Nora Sarvetnick

Journal Articles: Regenerative Medicine

The function of natural killer T (NKT) cells in the immune system has yet to be determined. There is some evidence that their defect is associated with autoimmunity, but it is still unclear how they play a role in regulating the pathogenesis of T cell-mediated autoimmune diseases. It was originally proposed that NKT cells could control autoimmunity by shifting the cytokine profile of autoimmune T cells toward a protective T helper 2 cell (Th2) type. However, it is now clear that the major function of NKT cells in the immune system is not related to their interleukin (IL)-4 secretion. In …

Insulinlike Growth Factor 1- And 2-Augmented Collagen Gel Repair Of Facial Osseous Defects, James S. Toung, Roy C. Ogle, Raymond F. Morgan, William H. Lindsey

School of Medical Diagnostics & Translational Sciences Publications

BACKGROUND: Defects of the facial bone structure are common problems for the facial plastic surgeon. Native type 1 collagen gels (T1CGs) have been shown to mediate repair of facial critical-size defects in rat models.

OBJECTIVE: To evaluate the efficacy of T1CG augmented with insulinlike growth factor (IGF) 1, IGF-2, and a combination of IGF-1 and IGF-2 on the repair of facial critical-size defects in a rodent model.

METHODS: Twenty-four retired male breeder Sprague-Dawley rats were divided into 4 groups of 6 animals. Facial critical-size defects were created by removing the nasalis bones with a bone-cutting drill. Defects were treated with …

Induction Of Integral Membrane Pam Expression In Att-20 Cells Alters The Storage And Trafficking Of Pomc And Pc1, Giuseppe D. Ciccotosto, Martin R. Schiller, Betty A. Eipper, Richard E. Mains

Life Sciences Faculty Research

Peptidylglycine alpha-amidating monooxygenase (PAM) is an essential enzyme that catalyzes the COOH-terminal amidation of many neuroendocrine peptides. The bifunctional PAM protein contains an NH2-terminal monooxygenase (PHM) domain followed by a lyase (PAL) domain and a transmembrane domain. The cytosolic tail of PAM interacts with proteins that can affect cytoskeletal organization. A reverse tetracycline-regulated inducible expression system was used to construct an AtT-20 corticotrope cell line capable of inducible PAM-1 expression. Upon induction, cells displayed a time- and dose-dependent increase in enzyme activity, PAM mRNA, and protein. Induction of increased PAM-1 expression produced graded changes in PAM-1 metabolism. Increased expression of …

Mechanisms Of Immunotherapeutic Intervention By Anti-Cd40l (Cd154) Antibody In An Animal Model Of Multiple Sclerosis, Laurence M. Howard, Amy J. Miga, Carol L. Vanderlugt, Mauro C. Dal Canto, John D. Laman, Randolph J. Noelle, Stephen D. Miller

Dartmouth Scholarship

Relapsing experimental autoimmune encephalomyelitis (R-EAE) in the SJL mouse is a Th1-mediated autoimmune demyelinating disease model for human multiple sclerosis and is characterized by infiltration of the central nervous system (CNS) by Th1 cells and macrophages. Disease relapses are mediated by T cells specific for endogenous myelin epitopes released during acute disease, reflecting a critical role for epitope spreading in the perpetuation of chronic central CNS pathology. We asked whether blockade of the CD40–CD154 (CD40L) costimulatory pathway could suppress relapses in mice with established R-EAE. Anti-CD154 antibody treatment at either the peak of acute disease or during remission effectively blocked …

Research Fundamentals: V. The Use Of Laboratory Animal Models In Research, Brian J. O'Neil, Jeffrey A. Kline, Keith Burkhart, John Younger

Biomedicine and Animal Models in Research Collection

Animal research has provided important information about many aspects of the pathophysiology of human disease. Well-performed animal studies can determine the potential benefit of many proposed therapeutic interventions, and experimental results from animal studies have served as the basis for many landmark clinical trials. Many animal research models are described in the research literature, and choosing the appropriate model to answer a research question can be a daunting task. Even more challenging is developing a new model when none of the existing systems are relevant to the proposed question. This article was prepared by members of the SAEM Research Committee …

Africa: An Integrated Curriculum Unit, Grades 2-4, Institute For The Development Of Gifted Education, Ricks Center For Gifted Children, University Of Denver

Ricks Curriculum Units Series

An integrated curriculum is an instructional approach that connects the disciplines to an underlying theme or topic. Immersing students in an integrated-thematic unit provides the backdrop for experiences to occur across the disciplines. Shaping coursework around integrated themes is especially appropriate for gifted students, however using an integrated-thematic curriculum is appropriate for all learners as it develops students' abilities to make connections, to solve problems by looking at multiple perspectives, and to integrate information from different fields of experience. An integrated-thematic curriculum permits students to be active participants in their own learning as they design their own explorations and take …

The Leukemic Protein Core Binding Factor Beta (Cbfbeta)-Smooth-Muscle Myosin Heavy Chain Sequesters Cbfalpha2 Into Cytoskeletal Filaments And Aggregates, Neeraj Adya, Terryl Stacy, Nancy A. Speck, Pu Paul Liu

Dartmouth Scholarship

The fusion gene CBFB-MYH11 is generated by the chromosome 16 inversion associated with acute myeloid leukemias. This gene encodes a chimeric protein involving the core binding factor β (CBFβ) and the smooth-muscle myosin heavy chain (SMMHC). Mouse model studies suggest that this chimeric protein CBFβ-SMMHC dominantly suppresses the function of CBF, a heterodimeric transcription factor composed of DNA binding subunits (CBFα1 to 3) and a non-DNA binding subunit (CBFβ). This dominant suppression results in the blockage of hematopoiesis in mice and presumably contributes to leukemogenesis. We used transient-transfection assays, in combination with immunofluorescence and green fluorescent protein-tagged proteins, to monitor …

Drosophila Unpaired Encodes A Secreted Protein That Activates The Jak Signaling Pathway, Douglas A. Harrison, Patricia E. Mccoon, Richard Binari, Michael Gilman, Norbert Perrimon

Biology Faculty Publications

In vertebrates, many cytokines and growth factors have been identified as activators of the JAK/STAT signaling pathway. In Drosophila, JAK and STAT molecules have been isolated, but no ligands or receptors capable of activating the pathway have been described. We have characterized the unpaired (upd) gene, which displays the same distinctive embryonic mutant defects as mutations in the Drosophila JAK (hopscotch) and STAT (stat92E) genes. Upd is a secreted protein, associated with the extracellular matrix, that activates the JAK pathway. We propose that Upd is a ligand that relies on JAK signaling to stimulate transcription of pair-rule genes in a …

Identification Of Putative Cytoskeletal Protein Homologues In The Protozoan Host Hartmannella Vermiformis As Substrates For Induced Tyrosine Phosphatase Activity Upon Attachment To The Legionnaires' Disease Bacterium, Legionella Pneumophila, Chandrasekar Venkataraman, Lian-Yang Gao, Subbarao Bondada, Yousef Abu Kwaik

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The Legionnaires' disease bacterium, Legionella pneumophila, is a facultative intracellular pathogen that invades and replicates within two evolutionarily distant hosts, free living protozoa and mammalian cells. Invasion and intracellular replication within protozoa are thought to be major factors in the transmission of Legionnaires' disease. We have recently reported the identification of a galactose/N-acetyl-d-galactosamine (Gal/GalNAc) lectin in the protozoan host Hartmannella vermiformis as a receptor for attachment and invasion by L. pneumophila (Venkataraman, C., B.J. Haack, S. Bondada, and Y.A. Kwaik. 1997. J. Exp. Med. 186:537–547). In this report, we extended our studies to the …

Molecular Basis For Effects Of Carcinogenic Heavy Metals On Inducible Gene Expression, Joshua W. Hamilton, Ronald C. Kaltreider, Olga V. Bajenova, Michael A. Ihnat, Jennifer Mccaffrey, Bruce W. Turpie, Erin E. Rowell, Jannet Oh, Michael J. Nemeth, Carrie A. Pesce, Jean P. Lariviere

Dartmouth Scholarship

Certain forms of the heavy metals arsenic and chromium are considered human carcinogens, although they are believed to act through very different mechanisms. Chromium(VI) is believed to act as a classic and mutagenic agent, and DNA/chromatin appears to be the principal target for its effects. In contrast, arsenic(III) is considered nongenotoxic, but is able to target specific cellular proteins, principally through sulfhydryl interactions. We had previously shown that various genotoxic chemical carcinogens, including chromium (VI), preferentially altered expression of several inducible genes but had little or no effect on constitutive gene expression. We were therefore interested in whether these carcinogenic …

In Vitro Assessment Of The Toxicity Of Cocaine And Its Metabolites In The Human Umbilical Artery, Tessa L. Long

Electronic Theses and Dissertations

An in vitro model was used to assess the effect of cocaine and its metabolites on the umbilical artery. Objectives were to pharmacologically confirm the presence of adrenergic innervation using tyramine, evaluate the ability of cocaine, benzoylecgonine, norcocaine and cocaethylene to potentiate vasoconstriction by serotonin and norepinephrine, examine the ability of ketanserin to block the enhanced vasoconstriction produced by cocaine, and determine displacement of 3 H-ketanserin by serotonin, norepinephrine, tyramine and mianserin. The vasoconstrictive effect of tyramine (100 μM) was enhanced in the presence of cocaine by 257%. Vasoconstrictive effects of serotonin and norepinephrine were significantly enhanced by cocaine by …

The Snare Machinery Is Involved In Apical Plasma Membrane Trafficking In Mdck Cells, Seng Hui Low, Steven J. Chapin, Christian Wimmer, Sidney W. Whiteheart, László G. Kömüves, Keith E. Mostov, Thomas Weimbs

Molecular and Cellular Biochemistry Faculty Publications

We have investigated the controversial involvement of components of the SNARE (soluble N-ethyl maleimide–sensitive factor [NSF] attachment protein [SNAP] receptor) machinery in membrane traffic to the apical plasma membrane of polarized epithelial (MDCK) cells. Overexpression of syntaxin 3, but not of syntaxins 2 or 4, caused an inhibition of TGN to apical transport and apical recycling, and leads to an accumulation of small vesicles underneath the apical plasma membrane. All other tested transport steps were unaffected by syntaxin 3 overexpression. Botulinum neurotoxin E, which cleaves SNAP-23, and antibodies against α-SNAP inhibit both TGN to apical and basolateral transport in …

Protein Production In The Milk Of Genetically Engineered Animals, Katherine M. Bates

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There are numerous proteins that have potential uses in commercial and scientific applications that are not utilized to their full potential. this is partly because it is not economically feasible to isolate some of these proteins from their natural sources or to produce them using bacterial fermentation methods. The purpose of this research was to target recombinant protein expression to the mammary glands of genetically engineered or transgenic animals. Foreign protein expression has been achieved in the mammary glands of rabbits, sheep, cows, and swine. By using a strong mammary gland promoter and signal peptide fused to the protein, it …

The Age Of The Kirkdale Cave Palaeofauna, Donald A. Mcfarlane, Derek C. Ford

WM Keck Science Faculty Papers

The Kirkdale Cave palaeofauna represents the original and classic 'warm', interglacial mammalian cave deposit in Britain. Although long considered to be 'Ipswichian' in age, no previous attempts to obtain radiometric dates have been recorded. Here we report a uranium-series disequilibrium date of 121,000 ± 4000 yr BP on a flowstone capping that overlay the original bone bed. The precision of the date exceeds that obtained at any other British Interglacial cave site, and permits tentative correlation with the high precision ice core records now available.