Cell and Developmental Biology | Open Access Articles

Live And Let Die: Regulatory Mechanisms In Fas-Mediated Apoptosis, James Curtin, Thomas Cotter

Articles

Activation of Fas receptor by Fas ligand causes caspase 8 activation and apoptosis in cells and is an important mechanism by which normal tissue homeostasis and function are maintained. Activation of caspase 8 is preceded by the formation of a death-inducing signalling complex (DISC), and a number of redundant mechanisms regulate DISC formation in vivo. Fas receptor is widely expressed in tissues, and dysfunction of the regulatory mechanisms in Fas receptor signalling has been reported in several diseases including autoimmune disease and cancer. This review aims to identify and discuss the various mechanisms employed by cells to alter their sensitivity …

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Defects In Death-Inducing Signalling Complex Formation Prevent Jnk Activation And Fas-Mediated Apoptosis In Du 145 Prostate Carcinoma Cells, James Curtin, Thomas Cotter

Articles

Androgen-independent prostate carcinomas are resistant to chemotherapy and cell lines derived from androgen-independent prostate carcinomas such as DU 145 cells are highly resistant to Fas-mediated apoptosis. The incubation of DU 145 cells with anti-Fas IgM agonistic antibody of Fas receptor fails to activate JNK, a stress kinase involved in regulating apoptosis. We have previously shown that JNK activation is sufficient and necessary to promote Fas-mediated apoptosis in DU 145 cells. We investigate the mechanisms by which JNK activation and apoptosis are abrogated. HSP27 is overexpressed in DU 145 cells and has previously been reported to sequester DAXX and prevent JNK …

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A Role For Yip1p In Copii Vesicle Biogenesis, Matthew Heidtman, Catherine Z. Chen, Ruth N. Collins, Charles Barlowe

Dartmouth Scholarship

Yeast Ypt1p-interacting protein (Yip1p) belongs to a conserved family of transmembrane proteins that interact with Rab GTPases. We encountered Yip1p as a constituent of ER-derived transport vesicles, leading us to hypothesize a direct role for this protein in transport through the early secretory pathway. Using a cell-free assay that recapitulates protein transport from the ER to the Golgi complex, we find that affinity-purified antibodies directed against the hydrophilic amino terminus of Yip1p potently inhibit transport. Surprisingly, inhibition is specific to the COPII-dependent budding stage. In support of this in vitro observation, strains bearing the temperature-sensitive yip1-4 allele accumulate ER membranes …

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Minus-End Capture Of Preformed Kinetochore Fibers Contributes To Spindle Morphogenesis, Alexey Khodjakov, Lily Copenagle, Michael B. Gordon, Duane A. Compton, Tarun M. Kapoor

Dartmouth Scholarship

Near-simultaneous three-dimensional fluorescence/differential interference contrast microscopy was used to follow the behavior of microtubules and chromosomes in living alpha-tubulin/GFP-expressing cells after inhibition of the mitotic kinesin Eg5 with monastrol. Kinetochore fibers (K-fibers) were frequently observed forming in association with chromosomes both during monastrol treatment and after monastrol removal. Surprisingly, these K-fibers were oriented away from, and not directly connected to, centrosomes and incorporated into the spindle by the sliding of their distal ends toward centrosomes via a NuMA-dependent mechanism. Similar preformed K-fibers were also observed during spindle formation in untreated cells. In addition, upon monastrol removal, centrosomes established a transient …

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Expression And Localization Of Estrogen Receptor-Alpha Protein In Normal And Abnormal Term Placentae And Stimulation Of Trophoblast Differentiation By Estradiol, A Bukovsky, Maria Cekanova Ms, Rndr, Phd, Mr Caudle, J Wimalasena, Js Foster, Dc Henley, Rf Elder

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

Estrogens play an important role in the regulation of placental function, and 17-beta-estradiol (E2) production rises eighty fold during human pregnancy. Although term placenta has been found to specifically bind estrogens, cellular localization of estrogen receptor alpha (ER-alpha) in trophoblast remains unclear. We used western blot analysis and immunohistochemistry with h-151 and ID5 monoclonal antibodies to determine the expression and cellular localization of ER-alpha protein in human placentae and cultured trophoblast cells. Western blot analysis revealed a ~65 kDa ER-alpha band in MCF-7 breast carcinoma cells (positive control). A similar band was detected in five normal term placentae exhibiting strong …

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Osmosensitive Taurine Release: Does Taurine Share The Same Efflux Pathway With Chloride And Other Amino Acid Osmolytes?, Rodrigo Franco

School of Veterinary and Biomedical Sciences: Faculty Publications

Swelling subsequent to hyposmotic conditions activates a process of volume regulation present in most cell types. This volume adjustment is accomplished by osmolyte translocation toward the extracellular space to reach a new osmotic equilibrium. Molecules involved in this homeostatic mechanism have been broadly classified into two categories: organic and inorganic osmolytes. Inorganic osmolytes comprise mainly the intracellular ions K⁺ and Cl^–. Cell swelling–induced activation of separate K⁺ and Cl^– channels has been described in most preparations. Organic osmolytes are grouped in three categories: amino acids, polyalcohols, and methylamines. These osmolytes, particularly taurine, are present in …

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Mucosal Priming Of Simian Immunodeficiency Virus-Specific Cytotoxic T-Lymphocyte Responses In Rhesus Macaques By The Salmonella Type Iii Secretion Antigen Delivery System, David T. Evans, Li-Mei Chen, Jacqueline Gillis, Kuei-Chin Lin, Brian Harty, Gail P. Mazzara, Ruben O. Donis, Keith G. Mansfield, Jeffrey D. Lifson, Ronald C. Desrosiers, Jorge E. Galán, R. Paul Johnson

School of Veterinary and Biomedical Sciences: Faculty Publications

Nearly all human immunodeficiency virus (HIV) infections are acquired mucosally, and the gut-associated lymphoid tissues are important sites for early virus replication. Thus, vaccine strategies designed to prime virus-specific cytotoxic T lymphocyte (CTL) responses that home to mucosal compartments may be particularly effective at preventing or containing HIV infection. The Salmonella type III secretion system has been shown to be an effective approach for stimulating mucosal CTL responses in mice. We therefore tested ∆phoP-phoQ attenuated strains of Salmonella enterica serovar Typhimurium and S. enterica serovar Typhi expressing fragments of the simian immunodeficiency virus (SIV) Gag protein fused to the …

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Method To Detect The Presence Of A Microorganism Or Agent In An Animal, David R. Smith, Laura L. Hungerford, Rodney A. Moxley, Susanne Hinkley, Terry Klopfenstein, Jeff Gray

School of Veterinary and Biomedical Sciences: Faculty Publications

The present invention provides a method to detect the presence of a microorganism or agent in an animal. The method encompasses placement of devices at various locations where the animal resides so as to induce the animal to initiate contact with the device. As a result of this contact, the animal deposits various microorganisms and agents on the device. The device is then tested for the presence of the particular microorganism or agent of interest.

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Placental Expression Of Estrogen Receptor Beta And Its Hormone Binding Variant – Comparison With Estrogen Receptor Alpha And A Role For Estrogen Receptors In Asymmetric Division And Differentiation Of Estrogen-Dependent Cells, Antonin Bukovsky, Michael R. Caudle, Maria Cekanova Ms, Rndr, Phd, Romaine I. Fernando, Jay Wimalasena, James S. Foster, Donald C. Henley, Robert F. Elder

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

During human pregnancy, the production of 17-beta-estradiol (E2) rises steadily to eighty fold at term, and placenta has been found to specifically bind estrogens. We have recently demonstrated the expression of estrogen receptor alpha (ER-alpha) protein in human placenta and its localization in villous cytotrophoblast (CT), vascular pericytes, and amniotic fibroblasts. In vitro, E2 stimulated development of large syncytiotrophoblast (ST) aggregates. In the present study we utilized ER-beta affinity purified polyclonal (N19:sc6820) and ER-alpha monoclonal (clone h-151) antibodies. Western blot analysis revealed a single ~52 kDa ER-beta band in chorionic villi (CV) protein extracts. In CV, strong cytoplasmic ER-beta immunoreactivity …

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Isovolumetric Regulation In Mammal Cells: Role Of Taurine, B. Ordaz, R. Franco, National University Of Mexico Tuz

School of Veterinary and Biomedical Sciences: Faculty Publications

The ability to regulate cell volume is an ancient conserved trait present in essentially all species through evolution. The maintenance of a constant cell volume is a homeostatic imperative in animal cells. Changes in cell water content affecting the concentration of intracellular messenger molecules impair the complex signaling network, crucial for cell functioning and intercellular communication. Although the renal homeostatic mechanisms exert a precise control of extracellular fluid osmolarity, this is challenged in a variety of pathological situations. The intracellular volume constancy is continuously compromised by the generation of local and transient osmotic microgradients, associated with nutrients uptake, secretion, cytoskeleton …

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Role Of Activator Protein-1 In The Down-Regulation Of The Human Cyp2j2 Gene In Hypoxia, Nicole Y. Marden, Eva Fiala-Beer, Shi-Hua Xiang, Michael Murray

School of Veterinary and Biomedical Sciences: Faculty Publications

The cytochrome P450 (CYP) 2J2 arachidonic acid epoxygenase gene was down-regulated at a pre-translational level in human hepatoma-derived HepG2 cells incubated in a hypoxic environment; under these conditions, the expression of c-Jun and c-Fos mRNA and protein was increased. The 5′-upstream region of the CYP2J2 gene was isolated by amplification of a 2341 bp fragment and putative regulatory elements that resembled activator protein-1 (AP-1)-like sequences were identified. From transient transfection analysis, c-Jun was found to strongly activate a CYP2J2–luciferase reporter construct, but co-transfection with plasmids encoding c-Fos or c-Fos-related antigens, Fra-1 and -2, abrogated reporter activity. Using a series …

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Demographic Assessment Of The Blue Crab (Callinectes Sapidus) In Chesapeake Bay Using Extractable Lipofuscins As Age Markers, Se-Jong Ju, David H. Secor, H. Rodger Harvey

OES Faculty Publications

The blue crab (Callinectes sapidus) plays an important economic and ecological role in estuaries and coastal habitats from the Gulf of Mexico to the east coast of North America, but demographic assessments are limited by length-based methods. We applied an alternative aging method using biochemical measures of metabolic byproducts (lipofuscins) sequestered in the neural tissue of eyestalks to examine population age structure. From Chesapeake Bay, subsamples of animals collected from the 1998-99 (n-769) and 1999-2000 (n=367) winter dredge surveys were collected and lipofuscin was measured. Modal analysis of the lipofuscin index provided separation into three modes, whereas carapace-width …

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Full-Text Articles in Cell and Developmental Biology

Live And Let Die: Regulatory Mechanisms In Fas-Mediated Apoptosis, James Curtin, Thomas Cotter

Articles

Defects In Death-Inducing Signalling Complex Formation Prevent Jnk Activation And Fas-Mediated Apoptosis In Du 145 Prostate Carcinoma Cells, James Curtin, Thomas Cotter

Articles

A Role For Yip1p In Copii Vesicle Biogenesis, Matthew Heidtman, Catherine Z. Chen, Ruth N. Collins, Charles Barlowe

Dartmouth Scholarship

Minus-End Capture Of Preformed Kinetochore Fibers Contributes To Spindle Morphogenesis, Alexey Khodjakov, Lily Copenagle, Michael B. Gordon, Duane A. Compton, Tarun M. Kapoor

Dartmouth Scholarship

Expression And Localization Of Estrogen Receptor-Alpha Protein In Normal And Abnormal Term Placentae And Stimulation Of Trophoblast Differentiation By Estradiol, A Bukovsky, Maria Cekanova Ms, Rndr, Phd, Mr Caudle, J Wimalasena, Js Foster, Dc Henley, Rf Elder

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

Osmosensitive Taurine Release: Does Taurine Share The Same Efflux Pathway With Chloride And Other Amino Acid Osmolytes?, Rodrigo Franco

School of Veterinary and Biomedical Sciences: Faculty Publications

School of Veterinary and Biomedical Sciences: Faculty Publications

Method To Detect The Presence Of A Microorganism Or Agent In An Animal, David R. Smith, Laura L. Hungerford, Rodney A. Moxley, Susanne Hinkley, Terry Klopfenstein, Jeff Gray

School of Veterinary and Biomedical Sciences: Faculty Publications

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

Isovolumetric Regulation In Mammal Cells: Role Of Taurine, B. Ordaz, R. Franco, National University Of Mexico Tuz

School of Veterinary and Biomedical Sciences: Faculty Publications

Role Of Activator Protein-1 In The Down-Regulation Of The Human Cyp2j2 Gene In Hypoxia, Nicole Y. Marden, Eva Fiala-Beer, Shi-Hua Xiang, Michael Murray

School of Veterinary and Biomedical Sciences: Faculty Publications

Demographic Assessment Of The Blue Crab (Callinectes Sapidus) In Chesapeake Bay Using Extractable Lipofuscins As Age Markers, Se-Jong Ju, David H. Secor, H. Rodger Harvey

OES Faculty Publications