Biochemistry, Biophysics, and Structural Biology Commons^™

Anisomycin Activates Jnk And Sensitises Du 145 Prostate Carcinoma Cells To Fas Mediated Apoptosis, James Curtin, Thomas Cotter

Articles

Treatment of the hormone refractory prostate cancer cell line DU 145 with sublethal concentrations of chemotherapeutic drugs has been reported to sensitise these cells to Fas mediated apoptosis. However, the mechanism by which this occurs has not been determined. Our group has shown that inhibition of JNK activity completely abrogates the effects of chemotherapeutic drugs. Using anisomycin, a potent JNK agonist, we have demonstrated a role for JNK in Fas mediated apoptosis in DU 145 cells. Inhibition of Caspase 8 and Caspase 9 completely inhibits this process which suggests that DU 145 cells require mitochondrial amplification of the Fas apoptotic …

Jun Dimerization Protein 2 Functions As A Progesterone Receptor N-Terminal Domain Coactivator, James S. Adelman, Suzanne E. Wardell, Viroj Boonyaratanakornkit, Ami Aronheim

James S. Adelman

The progesterone receptor (PR) contains two transcription activation function (AF) domains, constitutive AF-1 in the N terminus and AF-2 in the C terminus. AF-2 activity is mediated by a hormone-dependent interaction with a family of steroid receptor coactivators (SRCs). SRC-1 can also stimulate AF-1 activity through a secondary domain that interacts simultaneously with the primary AF-2 interaction site. Other protein interactions and mechanisms that mediate AF-1 activity are not well defined. By interaction cloning, we identified an AP-1 family member, Jun dimerization protein 2 (JDP-2), as a novel PR-interacting protein. JDP-2 was first defined as a c-Jun interacting protein that …

Involvement Of Platelet-Derived Growth Factor, Pdgf Receptor Signaling, Focal Adhesion Kinase And Src In Pressure-Induced Vascular Smooth Muscle Hypertrophy, Darian Clark Rice

Theses and Dissertations in Biomedical Sciences

Elevated blood pressure is associated with varying degrees of arterial remodeling. The mechanisms by which extracellular mechanical stress is converted into intracellular alterations in signal transduction and gene expression have yet to be fully elucidated. Our goal was to investigate the early events in the vascular smooth muscle response to acute hypertension and to identify mediators involved in long-term hypertensive remodeling.

In the acute phase of hypertension we targeted cell surface integrin and growth factor receptors thought to be mechanically sensitive. The signaling molecules FAK, Src and ERK-MAPK are known to be triggered by integrin engagement and growth factor receptor …

Characterizing Gene Expression During Lens Formation In Xenopus Laevis: Evaluating The Model For Embryonic Lens Induction, Brian Walter, Jonathan Henry, Maria Carinato, Jonathan Schaefer, Adam Wolfe, Brian Walter, Kimberly Perry, Tricia Elbl

Brian Walter

Few directed searches have been undertaken to identify the genes involved in vertebrate lens formation. In the frog Xenopus, the larval cornea can undergo a process of transdifferentiation to form a new lens once the original lens is removed. Based on preliminary evidence, we have shown that this process shares many elements of a common molecular/genetic pathway to that involved in embryonic lens development. A subtracted cDNA library, enriched for genes expressed during cornea-lens transdifferentiation, was prepared. The similarities/identities of specific clones isolated from the subtracted cDNA library define an expression profile of cells undergoing cornea-lens transdifferentiation ("lens regeneration") and …

Composition And Method For The Prevention And Treatment Of Oxidative Damage In Ocular Tissues, Marjorie F. Lou, Nalini Raghavachari;, Fengyu Qiao

School of Veterinary and Biomedical Sciences: Faculty Publications

Thioltransferase and derivatives thereof are provided. Methods of treating or preventing cataract formation comprosing administering thioltransferase or a derivative thereof are also provided. Thioltransferase or derivatives thereof are also useful for treating or preventing diseases resulting from or associated with oxidative stress. Human lens thioltransferase and a DNA sequence encoding the same are also provided.

Prostate Specific Membrane Antigen (Psma): Immunoassay Development And Characterization Of Transcriptional Regulation, Zhen Xiao

Theses and Dissertations in Biomedical Sciences

Prostate cancer (PCA) is the most common cancer and the second leading cause of death among American men. The high mortality is greatly attributed to the lack of early detection tools and effective treatment for metastasis and relapses. Biomarkers that can discriminate benign from malignant tumor and signal the development of androgen independent and metastatic tumor are needed. A biomarker designated prostate specific membrane antigen (PSMA) has the potential to fulfill this need. The objective of this study is to develop a clinically useful immunoassay for quantitation of serum PSMA and to study the molecular mechanism underlying the upregulation of …

Osmosensitive Release Of Neurotransmitter Amino Acids: Relevance And Mechanisms, Herminia Pasantes-Morales, Rodrigo Franco, Lenin Ochoa, Benito Ordaz

School of Veterinary and Biomedical Sciences: Faculty Publications

Hyposmolarity activates amino acid efflux as part of the corrective volume process in a variety of cells. This review discusses the mechanism of amino acid release in brain cells preparations. Results present evidence of substantial differences between the efflux of taurine and that of GABA and glu-tamate, which besides a possible role as osmolytes, have a main function as synaptic transmitters. The differences found concern the efflux time course, the sensitivity to Cl^– channel blockers, the modulation by tyrosine kinases, the influence of PKC and the effect of cytoskeleton disruptive agents. While taurine efflux features fit well with the …

Methods And Compositions For Protection Against Bovine Viral Diseases, Subramaniam Srikumaran

School of Veterinary and Biomedical Sciences: Faculty Publications

The present invention relates to methods and compositions for eliciting an immune response against bovine viral epitopes. The methods comprise combining at least one heat shock protein with at least one bovine viral epitope to form a purified epitope/heat shock protein complex and administration of an immune system stimulating amount of the purified epitope/heat shock protein complex. The compositions comprise, a purified epitope/heat shock protein complex comprising at least one bovine viral epitope complexed with at least one heat shock protein, and a pharmaceutically acceptable carrier, diluent or excipient.

Variability Of Placental Expression Of Cyclin E Low Molecular Weight Variants, A Bukovsky, Maria Cekanova Ms, Rndr, Phd, Mr Caudle, J Wimalasena, Js Foster, Ja Keenan, Rf Elder

Faculty Publications and Other Works -- Biochemistry, Cellular and Molecular Biology

No abstract provided.

Actin Dynamics Regulate Myosin Assembly In Muscle Cells, John Dylan Cook

Inquiry: The University of Arkansas Undergraduate Research Journal

During muscle cell (i.e. myocyte )development, organization of actin and myosin into the contractile unit (i.e. sarcomere) is required for proper muscle contraction. By disrupting the processes of muscle cell development, I am able to see which steps play important roles in proper maturation of myocytes. Elucidation of the key pathways in muscle development could lead to a better understanding of human cardiac hypertrophies and muscle myopathies. Since actin filament formation precedes myosin organization, I am using actin assembly inhibitors to determine if actin filaments are a necessary prerequisite for myosin organization. It is hypothesized that disruption of actin will …

Variability Of Placental Expression Of Cyclin E Low Molecular Weight Variants, A Bukovsky, Maria Cekanova Ms, Rndr, Phd, Mr Caudle, J Wimalasena, Js Foster, Ja Keenan, Rf Elder

Maria Cekanova MS, RNDr, PhD

No abstract provided.

Actin And Myosin Remodeling In The A7r5 Smooth Muscle Cell, Michael E. Fultz

Theses, Dissertations and Capstones

Active remodeling of the cytoskeleton has been proposed to contribute to the low energy cost and maintenance of the sustained contraction in smooth muscle. Using confocal microscopy and standard immunohistochemical techniques, direct observation of actin remodeling was studied in the contracting A7r5 cell in response to the diacylglycerol (DAG) analog phorbol 12, 13 dibutyrate (PDBu). -actin was shown to exist in the resting cell as parallel stress cables that extend across the cell. Stimulation by PDBu resulted in a sustained contraction that occurred in approximately eighty-five percent of the A7r5 cells. The initial contraction was not uniform, but primarily occurred …

Influence Of Protein Tyrosine Kinases On Cell Volume Change-Induced Taurine Release, Herminia Pasantes-Morales, Rodrigo Franco

School of Veterinary and Biomedical Sciences: Faculty Publications

Taurine efflux occurs in association with cell swelling in both hyposmotic and isosmotic conditions and during cell shrinkage in apoptotic death. Release occurs through a leak pathway, is largely Ca²⁺-independent and is sensitive to Cl^– channel blockers. Taurine efflux elicited by hyposmolarity is reduced or suppressed by tyrosine kinase blockers and increased by tyrosine phosphatase inhibitors. The specific kinases involved are still unknown and may be different in the various cell types. Non-receptor and scr-related protein kinases have been identified in some cells as elements that directly phosphorylate the taurine efflux pathway. Possible tyrosine kinase targets are …

Mechanisms Counteracting Swelling In Brain Cells During Hyponatremia, Herminia Pasantes-Morales, Rodrigo Franco, Benito Ordaz, Lenin D. Ochoa

School of Veterinary and Biomedical Sciences: Faculty Publications

Water gain in the brain consequent to hyponatremia is counteracted by mechanisms that initially include a compensatory displacement of liquid from the interstitial space to cerebrospinal fluid and systemic circulation and subsequently an active reduction in cell water accomplished by extrusion of intracellular osmolytes to reach osmotic equilibrium. Potassium (K⁺), chloride (Cl^–), amino acids, polyalcohols, and methylamines all contribute to volume regulation, with a major contribution of ions at the early phase and of organic osmolytes at the late phase of the regulatory process. Experimental models in vitro show that osmolyte fluxes occur via leak pathways …

Mechanism For Membrane Electroporation Irreversibility Under High-Intensity, Ultrashort Electrical Pulse Conditions, R. P. Joshi, K. H. Schoenbach

Bioelectrics Publications

An improved electroporation model is used to address membrane irreversibility under ultrashort electric pulse conditions. It is shown that membranes can survive a strong electric pulse and recover provided the pore distribution has a relatively large spread. If, however, the population consists predominantly of larger radii pores, then irreversibility can result. Physically, such a distribution could arise if pores at adjacent sites coalesce. The requirement of close proximity among the pore sites is more easily satisfied in smaller organelles than in outer cell membranes. Model predictions are in keeping with recent observations of cell damage to intracellular organelles (e.g., mitochondria), …

Theoretical Predictions Of Electromechanical Deformation Of Cells Subjected To High Voltages For Membrane Electroporation, R. P. Joshi, Q. Hu, K. H. Schoenbach, H. P. Hjalmarson

Bioelectrics Publications

An electromechanical analysis based on thin-shell theory is presented to analyze cell shape changes in response to external electric fields. This approach can be extended to include osmotic-pressure changes. Our calculations demonstrate that at large fields, the spherical cell geometry can be significantly modified, and even ellipsoidal forms would be inappropriate to account for the deformation. Values of the surface forces obtained from our calculations are in very good agreement with the 1–10 mN/m range for membrane rupture reported in the literature. The results, in keeping with reports in the literature, demonstrate that the final shape depends on membrane thickness. …

16s Ribosomal Dna Sequencing Confirms The Synonymy Of Vibrio Harveyi And V. Carchariae, Eric J. Gauger, Marta Gomez-Chiarri

Fisheries, Animal and Veterinary Sciences Faculty Publications

Seventeen bacterial strains previously identified as Vibrio harveyi (Baumann et al. 1981) or V. carchariae (Grimes et al. 1984) and the type strains of V. harveyi, V. carchariae and V. campbellii were analyzed by 16S ribosomal DNA (rDNA) sequencing. Four clusters were identified in a phylogenetic analysis performed by comparing a 746 base pair fragment of the 16S rDNA and previously published sequences of other closely related Vibrio species. The type strains of V. harveyi and V. carchariae and about half of the strains identified as V. harveyi or V. carchariae formed a single, wellsupported cluster designed as ‘bona …