WorldWideScience

Sample records for e1 glycoprotein involvement

  1. Isolation and characterization of broadly neutralizing human monoclonal antibodies to the e1 glycoprotein of hepatitis C virus

    DEFF Research Database (Denmark)

    Meunier, Jean-Christophe; Russell, Rodney S.; Goossens, Vera

    2008-01-01

    The relative importance of humoral and cellular immunity in the prevention or clearance of hepatitis C virus (HCV) infection is poorly understood. However, there is considerable evidence that neutralizing antibodies are involved in disease control. Here we describe the detailed analysis of human...... monoclonal antibodies (MAbs) directed against HCV glycoprotein E1, which may have the potential to control HCV infection. We have identified two MAbs that can strongly neutralize HCV-pseudotyped particles (HCVpp) bearing the envelope glycoproteins of genotypes 1a, 1b, 4a, 5a, and 6a and less strongly...... neutralize HCVpp bearing the envelope glycoproteins of genotype 2a. Genotype 3a was not neutralized. The epitopes for both MAbs were mapped to the region encompassing amino acids 313 to 327. In addition, robust neutralization was also observed against cell culture-adapted viruses of genotypes 1a and 2a...

  2. CYP2E1 Metabolism of Styrene Involves Allostery

    OpenAIRE

    2012-01-01

    We are the first to report allosterism during styrene oxidation by recombinant CYP2E1 and human liver microsomes. At low styrene concentrations, oxidation is inefficient because of weak binding to CYP2E1 (Ks = 830 μM). A second styrene molecule then binds CYP2E1 with higher affinity (Kss = 110 μM) and significantly improves oxidation to achieve a kcat of 6.3 nmol · min−1 · nmol CYP2E1−1. The transition between these metabolic cycles coincides with reported styrene concentrations in blood from...

  3. CYP2E1 Metabolism of Styrene Involves Allostery

    Science.gov (United States)

    Hartman, Jessica H.; Boysen, Gunnar

    2012-01-01

    We are the first to report allosterism during styrene oxidation by recombinant CYP2E1 and human liver microsomes. At low styrene concentrations, oxidation is inefficient because of weak binding to CYP2E1 (Ks = 830 μM). A second styrene molecule then binds CYP2E1 with higher affinity (Kss = 110 μM) and significantly improves oxidation to achieve a kcat of 6.3 nmol · min−1 · nmol CYP2E1−1. The transition between these metabolic cycles coincides with reported styrene concentrations in blood from exposed workers; thus, this CYP2E1 mechanism may be relevant in vivo. Scaled modeling of the in vitro-positive allosteric mechanism for styrene metabolism to its in vivo clearance led to significant deviations from the traditional model based on Michaelis-Menten kinetics. Low styrene levels were notably much less toxic than generally assumed. We interrogated the allosteric mechanism using the CYP2E1-specific inhibitor and drug 4-methylpyrazole, which we have shown binds two CYP2E1 sites. From the current studies, styrene was a positive allosteric effector on 4-methylpyrazole binding, based on a 10-fold increase in 4-methylpyrazole binding affinity from Ki 0.51 to Ksi 0.043 μM. The inhibitor was a negative allosteric effector on styrene oxidation, because kcat decreased 6-fold to 0.98 nmol · min−1 · nmol CYP2E1−1. Consequently, mixtures of styrene and other molecules can induce allosteric effects on binding and metabolism by CYP2E1 and thus mitigate the efficiency of their metabolism and corresponding effects on human health. Taken together, our elucidation of mechanisms for these allosteric reactions provides a powerful tool for further investigating the complexities of CYP2E1 metabolism of drugs and pollutants. PMID:22807108

  4. Structural models of the membrane anchors of envelope glycoproteins E1 and E2 from pestiviruses

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jimin, E-mail: jimin.wang@yale.edu; Li, Yue; Modis, Yorgo, E-mail: yorgo.modis@yale.edu

    2014-04-15

    The membrane anchors of viral envelope proteins play essential roles in cell entry. Recent crystal structures of the ectodomain of envelope protein E2 from a pestivirus suggest that E2 belongs to a novel structural class of membrane fusion machinery. Based on geometric constraints from the E2 structures, we generated atomic models of the E1 and E2 membrane anchors using computational approaches. The E1 anchor contains two amphipathic perimembrane helices and one transmembrane helix; the E2 anchor contains a short helical hairpin stabilized in the membrane by an arginine residue, similar to flaviviruses. A pair of histidine residues in the E2 ectodomain may participate in pH sensing. The proposed atomic models point to Cys987 in E2 as the site of disulfide bond linkage with E1 to form E1–E2 heterodimers. The membrane anchor models provide structural constraints for the disulfide bonding pattern and overall backbone conformation of the E1 ectodomain. - Highlights: • Structures of pestivirus E2 proteins impose constraints on E1, E2 membrane anchors. • Atomic models of the E1 and E2 membrane anchors were generated in silico. • A “snorkeling” arginine completes the short helical hairpin in the E2 membrane anchor. • Roles in pH sensing and E1–E2 disulfide bond formation are proposed for E1 residues. • Implications for E1 ectodomain structure and disulfide bonding pattern are discussed.

  5. Salmonid alphavirus glycoprotein E2 requires low temperature and E1 for virion formation and induction of protective immunity.

    Science.gov (United States)

    Hikke, Mia C; Braaen, Stine; Villoing, Stephane; Hodneland, Kjartan; Geertsema, Corinne; Verhagen, Lisa; Frost, Petter; Vlak, Just M; Rimstad, Espen; Pijlman, Gorben P

    2014-10-29

    Salmonid alphavirus (SAV; also known as Salmon pancreas disease virus; family Togaviridae) causes pancreas disease and sleeping disease in Atlantic salmon and rainbow trout, respectively, and poses a major burden to the aquaculture industry. SAV infection in vivo is temperature-restricted and progeny virus is only produced at low temperatures (10-15 °C). Using engineered SAV replicons we show that viral RNA replication is not temperature-restricted suggesting that the viral structural proteins determine low-temperature dependency. The processing/trafficking of SAV glycoproteins E1 and E2 as a function of temperature was investigated via baculovirus vectors in Sf9 insect cells and by transfection of CHSE-214 fish cells with DNA constructs expressing E1 and E2. We identified SAV E2 as the temperature determinant by demonstrating that membrane trafficking and surface expression of E2 occurs only at low temperature and only in the presence of E1. Finally, a vaccination-challenge model in Atlantic salmon demonstrates the biological significance of our findings and shows that SAV replicon DNA vaccines encoding E2 elicit protective immunity only when E1 is co-expressed. This is the first study that identifies E2 as the critical determinant of SAV low-temperature dependent virion formation and defines the prerequisites for induction of a potent immune response in Atlantic salmon by DNA vaccination.

  6. Deacylation of the transmembrane domains of Sindbis virus envelope glycoproteins E1 and E2 does not affect low-pH-induced viral membrane fusion activity

    NARCIS (Netherlands)

    Smit, JM; Bittman, R; Wilschut, J

    2001-01-01

    The envelope glycoproteins E1 and E2 of Sindbis virus are palmitoylated at cysteine residues within their transmembrane domains (E1 at position 430, and E2 at positions 388 and 390), Here, we investigated the in vitro membrane fusion activity of Sindbis virus variants (derived from the Tote 1101 inf

  7. Specifically Binding of L-ficolin to N-glycans of HCV Envelope Glycoproteins E1 and E2 Leads to Complement Activation

    Institute of Scientific and Technical Information of China (English)

    Jun Liu; Mohammed A.M.Ali; Yinghua Shi; Yinglan Zhao; Fenglin Luo; Jin Yu; Tian Xiang; Jie Tang; Dongqing Li; Quan Hu; Wenzhe Ho; Xiaolian Zhang

    2009-01-01

    L-ficolin and HCV E1 and E2 glycoproteins was attributed to the N-glycans of E1 and E2.These findings provide new insights into the biological functions of L-ficolin in clinically important hepatic viral diseases.

  8. Identification of key structural characteristics of Schisandra chinensis lignans involved in P-glycoprotein inhibition.

    Science.gov (United States)

    Slanina, Jiří; Páchniková, Gabriela; Carnecká, Martina; Porubová Koubíková, Ludmila; Adámková, Lenka; Humpa, Otakar; Smejkal, Karel; Slaninová, Iva

    2014-10-24

    The aim of the present study was to determine the structural requirements for dibenzocyclooctadiene lignans essential for P-glycoprotein inhibition. Altogether 15 structurally related lignans isolated from Schisandra chinensis or prepared by modification of their backbone were investigated, including three pairs of enantiomers. P-Glycoprotein inhibition was quantified using a doxorubicin accumulation assay in human promyelotic leukemia HL60/MDR cells overexpressing P-glycoprotein. A preliminary quantitative structure-activity relationship analysis revealed three main structural features involved in P-glycoprotein inhibition: a 1,2,3-trimethoxy moiety, a 6-acyloxy group, and the absence of a 7-hydroxy group. The most effective inhibitors, (-)-gomisin N (1) and (+)-deoxyschizandrin [(+)-2], were selected for further evaluation of their effects. Both these lignans restored the cytotoxic effect of doxorubicin in HL60/MDR cells and when combined with a subtoxic concentration of this compound increased the proportion of G2/M cells significantly, which is a usual response to treatment with this anticancer drug.

  9. HPV18 E1^E4 is assembled into aggresome-like compartment and involved in sequestration of viral oncoproteins.

    Directory of Open Access Journals (Sweden)

    Naoko eKajitani

    2013-08-01

    Full Text Available Papillomavirus is the etiological agent for warts and several squamous carcinomas. Skin cancer induced by cottontail rabbit papillomavirus (CRPV was the first animal model for virus-induced carcinogenesis. The target organ of the virus infection is stratified epithelium and virus replication is tightly regulated by the differentiation program of the host cell. E1^E4 protein is a viral gene product, and although it is considered to be involved in the control of virus replication, little is known about the biological role. We found that HPV18 E1^E4 was assembled into an aggresome-like compartment and was involved in sequestration of virus oncoproteins, which might contribute to the differentiation-dependent lifecycle of papillomavirus.

  10. The hepatitis C virus E1 glycoprotein undergoes productive folding but accelerated degradation when expressed as an individual subunit in CHO cells.

    Directory of Open Access Journals (Sweden)

    Valentina Botti

    Full Text Available Hepatitis C Virus E1E2 heterodimers are components of the viral spike. Although there is a general agreement on the necessity of the co-expression of both E1 and E2 on a single coding unit for their productive folding and assembly, in a previous study using an in vitro system we obtained strong indications that E1 can achieve folding in absence of E2. Here, we have studied the folding pathway of unescorted E1 from stably expressing CHO cells, compared to the folding observed in presence of the E2 protein. A DTT-resistant conformation is achieved by E1 in both situations, consistent with the presence of an E2-independent oxidative pathway. However, while the E1E2 heterodimer is stable inside cells, E1 expressed alone is degraded within a few hours. On the other hand, the oxidation and stability of individually expressed E2 subunits is dependent on E1 co-expression. These data are consistent with E1 and E2 assisting each other for correct folding via different mechanisms: E2 assists E1 by stabilizing a semi-native conformation meanwhile E1 drives E2 towards a productive folding pathway.

  11. Pharmacophore model of drugs involved in P-glycoprotein multidrug resistance: explanation of structural variety (hypothesis).

    Science.gov (United States)

    Pajeva, Ilza K; Wiese, Michael

    2002-12-19

    A general pharmacophore model of P-glycoprotein (P-gp) drugs is proposed that is based on a highly diverse data set and relates to the verapamil binding site of the protein. It is derived from structurally different drugs using the program GASP. The pharmacophore model consists of two hydrophobic points, three hydrogen bond (HB) acceptor points, and one HB donor point. Pharmacophore patterns of various drugs are obtained, and different binding modes are presumed for some of them. It is concluded that the binding affinity of the drugs depends on the number of the pharmacophore points simultaneously involved in the interaction with P-gp. On the basis of the obtained results, a hypothesis is proposed to explain the broad structural variety of the P-gp substrates and inhibitors: (i) the verapamil binding site of P-gp has several points that can participate in hydrophobic and HB interactions; (ii) different drugs can interact with different receptor points in different binding modes.

  12. Ammonia excretion in rainbow trout (Oncorhynchus mykiss): evidence for Rh glycoprotein and H+-ATPase involvement.

    Science.gov (United States)

    Nawata, C Michele; Hung, Carrie C Y; Tsui, Tommy K N; Wilson, Jonathan M; Wright, Patricia A; Wood, Chris M

    2007-11-14

    Branchial ammonia transport in freshwater teleosts is not well understood. Most studies conclude that NH(3) diffuses out of the gill and becomes protonated to NH(4)(+) in an acidified gill boundary layer. Rhesus (Rh) proteins are new members of the ammonia transporter superfamily and rainbow trout possess genes encoding for Rh30-like1 and Rhcg2. We identified seven additional full-length trout Rh cDNA sequences: one Rhag and two each of Rhbg, Rhcg1, and Rh30-like. The mRNA expression of Rhbg, Rhcg1, and Rhcg2 was examined in trout tissues (blood, brain, eye, gill, heart, intestine, kidney, liver, muscle, skin, spleen) exposed to high external ammonia (HEA; 1.5 mmol/l NH(4)HCO(3), pH 7.95, 15 degrees C). Rhbg was expressed in all tissues, Rhcg1 was expressed in brain, gill, liver, and skin, and Rhcg2 was expressed in gill and skin. Brain Rhbg and Rhcg1 were downregulated, blood Rh30-like and Rhag were downregulated, and skin Rhbg and Rhcg2 were upregulated with HEA. After an initial uptake of ammonia into the fish during HEA, excretion was reestablished, coinciding with upregulations of gill Rh mRNA in the pavement cell fraction: Rhcg2 at 12 and 48 h, and Rhbg at 48 h. NHE2 expression remained unchanged, but upregulated H(+)-ATPase (V-type, B-subunit) and downregulated carbonic anhydrase (CA2) expression and activity were noted in the gill and again expression changes occurred in pavement cells, and not in mitochondria-rich cells. Together, these results indicate Rh glycoprotein involvement in ammonia transport and excretion in the rainbow trout while underscoring the significance of gill boundary layer acidification by H(+)-ATPase.

  13. Protein N-glycosylation in Archaea: defining Haloferax volcanii genes involved in S-layer glycoprotein glycosylation.

    Science.gov (United States)

    Abu-Qarn, Mehtap; Eichler, Jerry

    2006-07-01

    In this study, characterization of the N-glycosylation process in the haloarchaea Haloferax volcanii was undertaken. Initially, putative Hfx. volcanii homologues of genes involved in eukaryal or bacterial N-glycosylation were identified by bioinformatics. Reverse transcription polymerase chain reaction (RT-PCR) confirmed that the proposed N-glycosylation genes are transcribed, indicative of true proteins being encoded. Where families of related gene sequences were detected, differential transcription of family members under a variety of physiological and environmental conditions was shown. Gene deletions point to certain genes, like alg11, as being essential yet revealed that others, such as the two versions of alg5, are not. Deletion of alg5-A did, however, lead to slower growth and interfered with surface (S)-layer glycoprotein glycosylation, as detected by modified migration on SDS-PAGE and glycostaining approaches. As deletion of stt3, the only component of the oligosaccharide transferase complex detected in Archaea, did not affect cell viability, it appears that N-glycosylation is not essential in Hfx. volcanii. Deletion of stt3 did, nonetheless, hinder both cell growth and S-layer glycoprotein glycosylation. Thus, with genes putatively involved in Hfx. volcanii protein glycosylation identified and the ability to address the roles played by the encoded polypeptides in modifying a reporter glycoprotein, the steps of the archaeal N-glycosylation pathway can be defined.

  14. Glycoprotein synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter G. (La Jolla, CA); Wang, Lei (San Diego, CA); Zhang, Zhiwen (San Diego, CA)

    2010-11-16

    Methods for making glycoproteins, both in vitro and in vivo, are provided. One method involves incorporating an unnatural amino acid into a protein and attaching one or more saccharide moieties to the unnatural amino acid. Another method involves incorporating an unnatural amino acid that includes a saccharide moiety into a protein. Proteins made by both methods can be further modified with additional sugars.

  15. Glycoprotein synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter G. (La Jolla, CA); Wang, Lei (San Diego, CA); Zhang, Zhiwen (San Diego, CA)

    2010-11-02

    Methods for making glycoproteins, both in vitro and in vivo, are provided. One method involves incorporating an unnatural amino acid into a protein and attaching one or more saccharide moieties to the unnatural amino acid. Another method involves incorporating an unnatural amino acid that includes a saccharide moiety into a protein. Proteins made by both methods can be further modified with additional sugars.

  16. Glycoprotein synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Methods for making glycoproteins, both in vitro and in vivo, are provided. One method involves incorporating an unnatural amino acid into a protein and attaching one or more saccharide moieties to the unnatural amino acid. Another method involves incorporating an unnatural amino acid that includes a saccharide moiety into a protein. Proteins made by both methods can be further modified with additional sugars.

    2009-07-14

    Methods for making glycoproteins, both in vitro and in vivo, are provided. One method involves incorporating an unnatural amino acid into a protein and attaching one or more saccharide moieties to the unnatural amino acid. Another method involves incorporating an unnatural amino acid that includes a saccharide moiety into a protein. Proteins made by both methods can be further modified with additional sugars.

  17. Evidence for P-Glycoprotein Involvement in Cell Volume Regulation Using Coulter Sizing in Flow Cytometry.

    Science.gov (United States)

    Pasquier, Jennifer; Rioult, Damien; Abu-Kaoud, Nadine; Hoarau-Véchot, Jessica; Marin, Matthieu; Le Foll, Frank

    2015-06-24

    The regulation of cell volume is an essential function that is coupled to a variety of physiological processes such as receptor recycling, excitability and contraction, cell proliferation, migration, and programmed cell death. Under stress, cells undergo emergency swelling and respond to such a phenomenon with a regulatory volume decrease (RVD) where they release cellular ions, and other osmolytes as well as a concomitant loss of water. The link between P-glycoprotein, a transmembrane transporter, and cell volume regulation is controversial, and changes in cells volume are measured using microscopy or electrophysiology. For instance, by using the patch-clamp method, our team demonstrated that chloride currents activated in the RVD were more intense and rapid in a breast cancer cell line overexpressing the P-glycoprotein (P-gp). The Cell Lab Quanta SC is a flow cytometry system that simultaneously measures electronic volume, side scatter and three fluorescent colors; altogether this provides unsurpassed population resolution and accurate cell counting. Therefore, here we propose a novel method to follow cellular volume. By using the Coulter-type channel of the cytometer Cell Lab Quanta SC MPL (multi-platform loading), we demonstrated a role for the P-gp during different osmotic treatments, but also a differential activity of the P-gp through the cell cycle. Altogether, our data strongly suggests a role of P-gp in cell volume regulation.

  18. Evidence for P-Glycoprotein Involvement in Cell Volume Regulation Using Coulter Sizing in Flow Cytometry

    Directory of Open Access Journals (Sweden)

    Jennifer Pasquier

    2015-06-01

    Full Text Available The regulation of cell volume is an essential function that is coupled to a variety of physiological processes such as receptor recycling, excitability and contraction, cell proliferation, migration, and programmed cell death. Under stress, cells undergo emergency swelling and respond to such a phenomenon with a regulatory volume decrease (RVD where they release cellular ions, and other osmolytes as well as a concomitant loss of water. The link between P-glycoprotein, a transmembrane transporter, and cell volume regulation is controversial, and changes in cells volume are measured using microscopy or electrophysiology. For instance, by using the patch-clamp method, our team demonstrated that chloride currents activated in the RVD were more intense and rapid in a breast cancer cell line overexpressing the P-glycoprotein (P-gp. The Cell Lab Quanta SC is a flow cytometry system that simultaneously measures electronic volume, side scatter and three fluorescent colors; altogether this provides unsurpassed population resolution and accurate cell counting. Therefore, here we propose a novel method to follow cellular volume. By using the Coulter-type channel of the cytometer Cell Lab Quanta SC MPL (multi-platform loading, we demonstrated a role for the P-gp during different osmotic treatments, but also a differential activity of the P-gp through the cell cycle. Altogether, our data strongly suggests a role of P-gp in cell volume regulation.

  19. Involvement of Leishmania donovani major surface glycoprotein gp63 in promastigote multiplication

    Indian Academy of Sciences (India)

    Sanjeev Pandey; Phuljhuri Chakraborti; Rakhi Sharma; Santu Bandyopadhyay; Dwijen Sarkar; Samit Adhya

    2004-03-01

    The major surface glycoprotein gp63 of the kinetoplastid protozoal parasite Leishmania is implicated as a ligand mediating uptake of the parasite into, and survival within, the host macrophage. By expressing gp63 antisense RNA from an episomal vector in L. donovani promastigotes, gp63-deficient transfectants were obtained. Reduction of the gp63 level resulted in increased generation times, altered cell morphology, accumulation of cells in the G2/M phase of the cell cycle, and increased numbers of binucleate cells with one or two kinetoplasts. Growth was stimulated, and the number of binucleate cells reduced, by addition to the culture of a bacterially expressed fusion protein containing the fibronectin-like SRYD motif and the zinc-binding (metalloprotease) domain of gp63. These observations support an additional role of gp63 in promastigote multiplication; the fibronectin-like properties of gp63 may be important in this process.

  20. Albumin is synthesized in epididymis and aggregates in a high molecular mass glycoprotein complex involved in sperm-egg fertilization.

    Science.gov (United States)

    Arroteia, Kélen Fabíola; Barbieri, Mainara Ferreira; Souza, Gustavo Henrique Martins Ferreira; Tanaka, Hiromitsu; Eberlin, Marcos Nogueira; Hyslop, Stephen; Alvares, Lúcia Elvira; Pereira, Luís Antonio Violin Dias

    2014-01-01

    The epididymis has an important role in the maturation of sperm for fertilization, but little is known about the epididymal molecules involved in sperm modifications during this process. We have previously described the expression pattern for an antigen in epididymal epithelial cells that reacts with the monoclonal antibody (mAb) TRA 54. Immunohistochemical and immunoblotting analyses suggest that the epitope of the epididymal antigen probably involves a sugar moiety that is released into the epididymal lumen in an androgen-dependent manner and subsequently binds to luminal sperm. Using column chromatography, SDS-PAGE with in situ digestion and mass spectrometry, we have identified the protein recognized by mAb TRA 54 in mouse epididymal epithelial cells. The ∼65 kDa protein is part of a high molecular mass complex (∼260 kDa) that is also present in the sperm acrosomal vesicle and is completely released after the acrosomal reaction. The amino acid sequence of the protein corresponded to that of albumin. Immunoprecipitates with anti-albumin antibody contained the antigen recognized by mAb TRA 54, indicating that the epididymal molecule recognized by mAb TRA 54 is albumin. RT-PCR detected albumin mRNA in the epididymis and fertilization assays in vitro showed that the glycoprotein complex containing albumin was involved in the ability of sperm to recognize and penetrate the egg zona pellucida. Together, these results indicate that epididymal-derived albumin participates in the formation of a high molecular mass glycoprotein complex that has an important role in egg fertilization.

  1. Involvement of P-glycoprotein in regulating cellular levels of Ginkgo flavonols: quercetin, kaempferol, and isorhamnetin.

    Science.gov (United States)

    Wang, Yi; Cao, Jiang; Zeng, Su

    2005-06-01

    Quercetin, kaempferol, and isorhamnetin were the most important flavonoid constituents in extracts from Ginkgo biloba leaves. Transport studies of Ginkgo flavonols were performed in Caco-2 cell mono-layers. Their apparent permeability in absorptive and secretion directions was determined, and quercetin, kaempferol and isorhamnetin displayed polarized transport, with the Papp,B-A being higher than the Papp,A-B (Pisorhamnetin, Student's t-test). Bcap37/MDR1 cells, which were transfected with a P-glycoprotein (P-gp) gene construct, were treated with quercetin, kaempferol or isorhamnetin. The concentrations of Ginkgo flavonol in Bcap37/MDR1 cells were lower than those in parent cells (Pisorhamnetin, Mann-Whitney U test). The concentrations of the flavonol in transfected cells increased when incubated with the P-gp inhibitor verapamil (Pisorhamnetin stimulated the ATPase activity (Pisorhamnetin, Mann Whitney U test). The results indicated that Ginkgo flavonols quercetin, kaempferol and isorhamnetin were substrates of P-gp. The P-gp type efflux pump might limit the bioavailability of Ginkgo flavonols.

  2. The UL24 protein of herpes simplex virus 1 affects the sub-cellular distribution of viral glycoproteins involved in fusion

    Energy Technology Data Exchange (ETDEWEB)

    Ben Abdeljelil, Nawel; Rochette, Pierre-Alexandre; Pearson, Angela, E-mail: angela.pearson@iaf.inrs.ca

    2013-09-15

    Mutations in UL24 of herpes simplex virus type 1 can lead to a syncytial phenotype. We hypothesized that UL24 affects the sub-cellular distribution of viral glycoproteins involved in fusion. In non-immortalized human foreskin fibroblasts (HFFs) we detected viral glycoproteins B (gB), gD, gH and gL present in extended blotches throughout the cytoplasm with limited nuclear membrane staining; however, in HFFs infected with a UL24-deficient virus (UL24X), staining for the viral glycoproteins appeared as long, thin streaks running across the cell. Interestingly, there was a decrease in co-localized staining of gB and gD with F-actin at late times in UL24X-infected HFFs. Treatment with chemical agents that perturbed the actin cytoskeleton hindered the formation of UL24X-induced syncytia in these cells. These data support a model whereby the UL24 syncytial phenotype results from a mislocalization of viral glycoproteins late in infection. - Highlights: • UL24 affects the sub-cellular distribution of viral glycoproteins required for fusion. • Sub-cellular distribution of viral glycoproteins varies in cell-type dependent manner. • Drugs targeting actin microfilaments affect formation of UL24-related syncytia in HFFs.

  3. Differentially expressed genes and signalling pathways are involved in mouse osteoblast-like MC3T3-E1 cells exposed to 17-b estradiol

    Institute of Scientific and Technical Information of China (English)

    Zhen-Zhen Shang; Xin Li; Hui-Qiang Sun; Guo-Ning Xiao; Cun-Wei Wang; Qi Gong

    2014-01-01

    Oestrogen is essential for maintaining bone mass, and it has been demonstrated to induce osteoblast proliferation and bone formation. In this study, complementary DNA (cDNA) microarrays were used to identify and study the expression of novel genes that may be involved in MC3T3-E1 cells’ response to 17-b estradiol. MC3T3-E1 cells were inoculated in minimum essential media alpha (a-MEM) cell culture supplemented with 17-b estradiol at different concentrations and for different time periods. MC3T3-E1 cells treated with 1028 mol?L21 17-b estradiol for 5 days exhibited the highest proliferation and alkaline phosphatase (ALP) activity;thus, this group was chosen for microarray analysis. The harvested RNA was used for microarray hybridisation and subsequent real-time reverse transcription polymerase chain reaction (RT-PCR) to validate the expression levels for selected genes. The microarray results were analysed using both functional and pathway analysis. In this study, microarray analysis detected 5 403 differentially expressed genes, of which 1 996 genes were upregulated and 3 407 genes were downregulated, 1 553 different functional classifications were identified by gene ontology (GO) analysis and 53 different pathways were involved based on pathway analysis. Among the differentially expressed genes, a portion not previously reported to be associated with the osteoblast response to oestrogen was identified. These findings clearly demonstrate that the expression of genes related to osteoblast proliferation, cell differentiation, collagens and transforming growth factor beta (TGF-b)-related cytokines increases, while the expression of genes related to apoptosis and osteoclast differentiation decreases, following the exposure of MC3T3-E1 cells to a-MEM supplemented with 17-b estradiol. Microarray analysis with functional gene classification is critical for a complete understanding of complementary intracellular processes. This microarray analysis provides large

  4. Immunolocalization of UDP-glucose:glycoprotein glucosyltransferase indicates involvement of pre-Golgi intermediates in protein quality control.

    Science.gov (United States)

    Zuber, C; Fan, J Y; Guhl, B; Parodi, A; Fessler, J H; Parker, C; Roth, J

    2001-09-11

    The UDP-glucose:glycoprotein glucosyltransferase (GT) is a protein folding sensor and glycosyltransferase that constitutes an important component of the protein quality control machinery. With the use of quantitative immunogold electron microscopy, we established the subcellular distribution of GT in rat liver and pancreas and Drosophila melanogaster salivary gland as well as cell lines and correlated it with that of glucosidase II, calreticulin, and pre-Golgi intermediate markers. Labeling for GT, as well as for glucosidase II and calreticulin, was found in the endoplasmic reticulum (ER), including nuclear envelope and pre-Golgi intermediates located between ER and Golgi apparatus, and in the cell periphery. In the rough ER, labeling for GT was inhomogeneous, with variously sized labeled and unlabeled cisternal regions alternating, indicative of a meshwork of quality control checkpoints. Notably, labeling intensity for GT was highest in pre-Golgi intermediates, corresponding to twice that of rough ER, whereas the Golgi apparatus exhibited no specific labeling. These results suggest that protein quality control is not restricted to the ER and that the pre-Golgi intermediates, by virtue of the presence of GT, glucosidase II, and calreticulin, are involved in this fundamental cellular process.

  5. The UL24 protein of herpes simplex virus 1 affects the sub-cellular distribution of viral glycoproteins involved in fusion.

    Science.gov (United States)

    Ben Abdeljelil, Nawel; Rochette, Pierre-Alexandre; Pearson, Angela

    2013-09-01

    Mutations in UL24 of herpes simplex virus type 1 can lead to a syncytial phenotype. We hypothesized that UL24 affects the sub-cellular distribution of viral glycoproteins involved in fusion. In non-immortalized human foreskin fibroblasts (HFFs) we detected viral glycoproteins B (gB), gD, gH and gL present in extended blotches throughout the cytoplasm with limited nuclear membrane staining; however, in HFFs infected with a UL24-deficient virus (UL24X), staining for the viral glycoproteins appeared as long, thin streaks running across the cell. Interestingly, there was a decrease in co-localized staining of gB and gD with F-actin at late times in UL24X-infected HFFs. Treatment with chemical agents that perturbed the actin cytoskeleton hindered the formation of UL24X-induced syncytia in these cells. These data support a model whereby the UL24 syncytial phenotype results from a mislocalization of viral glycoproteins late in infection.

  6. A p53-independent apoptotic mechanism of adenoviral mutant E1A was involved in its selective antitumor activity for human cancer

    Science.gov (United States)

    Fang, Lin; Cheng, Qian; Zhao, Jingjing; Ge, Yan; Zhu, Qi; Zhao, Min; Zhang, Jie; Zhang, Qi; Li, Liantao; Liu, Junjie; Zheng, Junnian

    2016-01-01

    The conserved regions (CR) of adenoviral E1A had been shown to be necessary for disruption of pRb-E2F transcription factor complexes and induction of the S phase. Here we constructed a mutant adenoviral E1A with Rb-binding ability absent (E1A 30-60aa and 120-127aa deletion, mE1A) and investigated its antitumor capacities in vitro and in vivo. The mE1A suppressed the viability of tumor cells as efficiently as the wild type E1A, and there was no cytotoxic effect on normal cells. Although the mE1A arrested tumor cell cycle with the same manner as E1A, the former played a different role on cell cycle regulation compared with E1A in normal cells, which might contribute to its selective antitumor activity. E1A and mE1A had accumulated inactive p53, decreased the expression of mdm2, Cdkn1a (also named p21), increased p21's nuclear distribution and induced tumor cell apoptosis in a p53-indenpent manner. Further, E1A or mE1A significantly suppressed tumor growth in subcutaneous hepatocellular carcinoma xenograft models. Especially, tumor-bearing mice treated with mE1A had higher survival rate than those treated with E1A. Our data demonstrated that mutant adenoviral E1A significantly induced tumor cell apoptosis in a p53-indenpednt manner and had selective tumor suppressing ability. The observations of adenoviral E1A mutant had provided a novel mechanism for E1A's complex activities during infection. PMID:27340782

  7. A computational approach identifies two regions of Hepatitis C Virus E1 protein as interacting domains involved in viral fusion process.

    Science.gov (United States)

    Bruni, Roberto; Costantino, Angela; Tritarelli, Elena; Marcantonio, Cinzia; Ciccozzi, Massimo; Rapicetta, Maria; El Sawaf, Gamal; Giuliani, Alessandro; Ciccaglione, Anna Rita

    2009-07-29

    The E1 protein of Hepatitis C Virus (HCV) can be dissected into two distinct hydrophobic regions: a central domain containing an hypothetical fusion peptide (FP), and a C-terminal domain (CT) comprising two segments, a pre-anchor and a trans-membrane (TM) region. In the currently accepted model of the viral fusion process, the FP and the TM regions are considered to be closely juxtaposed in the post-fusion structure and their physical interaction cannot be excluded. In the present study, we took advantage of the natural sequence variability present among HCV strains to test, by purely sequence-based computational tools, the hypothesis that in this virus the fusion process involves the physical interaction of the FP and CT regions of E1. Two computational approaches were applied. The first one is based on the co-evolution paradigm of interacting peptides and consequently on the correlation between the distance matrices generated by the sequence alignment method applied to FP and CT primary structures, respectively. In spite of the relatively low random genetic drift between genotypes, co-evolution analysis of sequences from five HCV genotypes revealed a greater correlation between the FP and CT domains than respect to a control HCV sequence from Core protein, so giving a clear, albeit still inconclusive, support to the physical interaction hypothesis.The second approach relies upon a non-linear signal analysis method widely used in protein science called Recurrence Quantification Analysis (RQA). This method allows for a direct comparison of domains for the presence of common hydrophobicity patterns, on which the physical interaction is based upon. RQA greatly strengthened the reliability of the hypothesis by the scoring of a lot of cross-recurrences between FP and CT peptides hydrophobicity patterning largely outnumbering chance expectations and pointing to putative interaction sites. Intriguingly, mutations in the CT region of E1, reducing the fusion process in

  8. Partial purification and characterization of a mannosyl transferase involved in O -linked mannosylation of glycoproteins in Candida albicans.

    Science.gov (United States)

    Arroyo-Flores, Blanca L; Calvo-Méndez, Carlos; Flores-Carreón, Arturo; López-Romero, Everardo

    2004-04-01

    Incubation of a mixed membrane fraction of C. albicans with the nonionic detergents Nonidet P-40 or Lubrol solubilized a fraction that catalyzed the transfer of mannose either from endogenously generated or exogenously added dolichol-P-[14C]Man onto endogenous protein acceptors. The protein mannosyl transferase solubilized with Nonidet P-40 was partially purified by a single step of preparative nondenaturing electrophoresis and some of its properties were investigated. Although transfer activity occurred in the absence of exogenous mannose acceptors and thus depended on acceptor proteins isolated along with the enzyme, addition of the protein fraction obtained after chemical de-mannosylation of glycoproteins synthesized in vitro stimulated mannoprotein labeling in a concentration-dependent manner. Other de-mannosylated glycoproteins, such as yeast invertase or glycoproteins extracted from C. albicans, failed to increase the amount of labeled mannoproteins. Mannosyl transfer activity was not influenced by common metal ions such as Mg(2+), Mn(2+) and Ca(2+), but it was stimulated up to 3-fold by EDTA. Common phosphoglycerides such as phosphatidylglycerol and, to a lower extent, phosphatidylinositol and phosphatidylcholine enhanced transfer activity. Interestingly, coupled transfer activity between dolichol phosphate mannose synthase, i.e., the enzyme responsible for Dol-P-Man synthesis, and protein mannosyl transferase could be reconstituted in vitro from the partially purified transferases, indicating that this process can occur in the absence of cell membranes.

  9. Identification of Interactions in the E1E2 Heterodimer of Hepatitis C Virus Important for Cell Entry*

    Science.gov (United States)

    Maurin, Guillemette; Fresquet, Judith; Granio, Ophélia; Wychowski, Czeslaw; Cosset, François-Loïc; Lavillette, Dimitri

    2011-01-01

    Several conserved domains critical for E1E2 assembly and hepatitis C virus entry have been identified in E1 and E2 envelope glycoproteins. However, the role of less conserved domains involved in cross-talk between either glycoprotein must be defined to fully understand how E1E2 undergoes conformational changes during cell entry. To characterize such domains and to identify their functional partners, we analyzed a set of intergenotypic E1E2 heterodimers derived from E1 and E2 of different genotypes. The infectivity of virions indicated that Con1 E1 did not form functional heterodimers when associated with E2 from H77. Biochemical analyses demonstrated that the reduced infectivity was not related to alteration of conformation and incorporation of Con1 E1/H77 E2 heterodimers but rather to cell entry defects. Thus, we generated chimeric E1E2 glycoproteins by exchanging different domains of each protein in order to restore functional heterodimers. We found that both the ectodomain and transmembrane domain of E1 influenced infectivity. Site-directed mutagenesis highlighted the role of amino acids 359, 373, and 375 in transmembrane domain in entry. In addition, we identified one domain involved in entry within the N-terminal part of E1, and we isolated a motif at position 219 that is critical for H77 function. Interestingly, using additional chimeric E1E2 complexes harboring substitutions in this motif, we found that the transmembrane domain of E1 acts as a partner of this motif. Therefore, we characterized domains of E1 and E2 that have co-evolved inside a given genotype to optimize their interactions and allow efficient entry. PMID:21555519

  10. Structures and Functions of Pestivirus Glycoproteins: Not Simply Surface Matters

    Directory of Open Access Journals (Sweden)

    Fun-In Wang

    2015-06-01

    Full Text Available Pestiviruses, which include economically important animal pathogens such as bovine viral diarrhea virus and classical swine fever virus, possess three envelope glycoproteins, namely Erns, E1, and E2. This article discusses the structures and functions of these glycoproteins and their effects on viral pathogenicity in cells in culture and in animal hosts. E2 is the most important structural protein as it interacts with cell surface receptors that determine cell tropism and induces neutralizing antibody and cytotoxic T-lymphocyte responses. All three glycoproteins are involved in virus attachment and entry into target cells. E1-E2 heterodimers are essential for viral entry and infectivity. Erns is unique because it possesses intrinsic ribonuclease (RNase activity that can inhibit the production of type I interferons and assist in the development of persistent infections. These glycoproteins are localized to the virion surface; however, variations in amino acids and antigenic structures, disulfide bond formation, glycosylation, and RNase activity can ultimately affect the virulence of pestiviruses in animals. Along with mutations that are driven by selection pressure, antigenic differences in glycoproteins influence the efficacy of vaccines and determine the appropriateness of the vaccines that are currently being used in the field.

  11. Cytochrome P450 and P-Glycoprotein-Mediated Interactions Involving African Herbs Indicated for Common Noncommunicable Diseases

    Directory of Open Access Journals (Sweden)

    Gregory Ondieki

    2017-01-01

    Full Text Available Herbal remedies are regularly used to complement conventional therapies in the treatment of various illnesses in Africa. This may be because they are relatively cheap and easily accessible and are believed by many to be safe, cause fewer side effects, and are less likely to cause dependency. On the contrary, many herbs have been shown to alter the pharmacokinetics of coadministered allopathic medicines and can either synergize or antagonize therapeutic effects as well as altering the toxicity profiles of these drugs. Current disease burden data point towards epidemiological transitions characterised by increasing urbanization and changing lifestyles, risk factors for chronic diseases like hypertension, diabetes, and cancer which often present as multimorbidities. As a result, we highlight African herb-drug interactions (HDIs modulated via cytochrome P450 enzyme family (CYP and P-glycoprotein (P-gp and the consequences thereof in relation to antihypertensive, antidiabetic, and anticancer drugs. CYPs are enzymes which account for to up to 70% of drug metabolism while P-gp is an efflux pump that extrudes drug substrates out of cells. Consequently, regulation of the relative activity of both CYP and P-gp by African herbs influences the effective drug concentration at the site of action and modifies therapeutic outcomes.

  12. Cytochrome P450 and P-Glycoprotein-Mediated Interactions Involving African Herbs Indicated for Common Noncommunicable Diseases

    Science.gov (United States)

    Kikete, Siambi; Liang, Rongjia; Wang, Lili

    2017-01-01

    Herbal remedies are regularly used to complement conventional therapies in the treatment of various illnesses in Africa. This may be because they are relatively cheap and easily accessible and are believed by many to be safe, cause fewer side effects, and are less likely to cause dependency. On the contrary, many herbs have been shown to alter the pharmacokinetics of coadministered allopathic medicines and can either synergize or antagonize therapeutic effects as well as altering the toxicity profiles of these drugs. Current disease burden data point towards epidemiological transitions characterised by increasing urbanization and changing lifestyles, risk factors for chronic diseases like hypertension, diabetes, and cancer which often present as multimorbidities. As a result, we highlight African herb-drug interactions (HDIs) modulated via cytochrome P450 enzyme family (CYP) and P-glycoprotein (P-gp) and the consequences thereof in relation to antihypertensive, antidiabetic, and anticancer drugs. CYPs are enzymes which account for to up to 70% of drug metabolism while P-gp is an efflux pump that extrudes drug substrates out of cells. Consequently, regulation of the relative activity of both CYP and P-gp by African herbs influences the effective drug concentration at the site of action and modifies therapeutic outcomes.

  13. The shell matrix of the freshwater mussel Unio pictorum (Paleoheterodonta, Unionoida). Involvement of acidic polysaccharides from glycoproteins in nacre mineralization.

    Science.gov (United States)

    Marie, Benjamin; Luquet, Gilles; Pais De Barros, Jean-Paul; Guichard, Nathalie; Morel, Sylvain; Alcaraz, Gérard; Bollache, Loïc; Marin, Frédéric

    2007-06-01

    Among molluscs, the shell biomineralization process is controlled by a set of extracellular macromolecular components secreted by the calcifying mantle. In spite of several studies, these components are mainly known in bivalves from only few members of pteriomorph groups. In the present case, we investigated the biochemical properties of the aragonitic shell of the freshwater bivalve Unio pictorum (Paleoheterodonta, Unionoida). Analysis of the amino acid composition reveals a high amount of glycine, aspartate and alanine in the acid-soluble extract, whereas the acid-insoluble one is rich in alanine and glycine. Monosaccharidic analysis indicates that the insoluble matrix comprises a high amount of glucosamine. Furthermore, a high ratio of the carbohydrates of the soluble matrix is sulfated. Electrophoretic analysis of the acid-soluble matrix revealed discrete bands. Stains-All, Alcian Blue, periodic acid/Schiff and autoradiography with (45)Ca after electrophoretic separation revealed three major polyanionic calcium-binding glycoproteins, which exhibit an apparent molecular mass of 95, 50 and 29 kDa, respectively. Two-dimensional gel electrophoresis shows that these bands, provisionally named P95, P50 and P29, are composed of numerous isoforms, the majority of which have acidic isoelectric points. Chemical deglycosylation of the matrix with trifluoromethanesulfonic acid induces a drastic shift of both the apparent molecular mass and the isoelectric point of these matrix components. This treatment induces also a modification of the shape of CaCO(3) crystals grown in vitro and a loss of the calcium-binding ability of two of the main matrix proteins (P95 and P50). Our findings strongly suggest that post-translational modifications display important functions in mollusc shell calcification.

  14. Hepatitis C Virus E1 and E2 Proteins Used as Separate Immunogens Induce Neutralizing Antibodies with Additive Properties.

    Science.gov (United States)

    Beaumont, Elodie; Roch, Emmanuelle; Chopin, Lucie; Roingeard, Philippe

    2016-01-01

    Various strategies involving the use of hepatitis C virus (HCV) E1 and E2 envelope glycoproteins as immunogens have been developed for prophylactic vaccination against HCV. However, the ideal mode of processing and presenting these immunogens for effective vaccination has yet to be determined. We used our recently described vaccine candidate based on full-length HCV E1 or E2 glycoproteins fused to the heterologous hepatitis B virus S envelope protein to compare the use of the E1 and E2 proteins as separate immunogens with their use as the E1E2 heterodimer, in terms of immunogenetic potential and the capacity to induce neutralizing antibodies. The specific anti-E1 and anti-E2 antibody responses induced in animals immunized with vaccine particles harboring the heterodimer were profoundly impaired with respect to those in animals immunized with particles harboring E1 and E2 separately. Moreover, the anti-E1 and anti-E2 antibodies had additive neutralizing properties that increase the cross-neutralization of heterologous strains of various HCV genotypes, highlighting the importance of including both E1 and E2 in the vaccine for an effective vaccination strategy. Our study has important implications for the optimization of HCV vaccination strategies based on HCV envelope proteins, regardless of the platform used to present these proteins to the immune system.

  15. Hepatitis C Virus E1 and E2 Proteins Used as Separate Immunogens Induce Neutralizing Antibodies with Additive Properties

    Science.gov (United States)

    Beaumont, Elodie; Roch, Emmanuelle; Chopin, Lucie; Roingeard, Philippe

    2016-01-01

    Various strategies involving the use of hepatitis C virus (HCV) E1 and E2 envelope glycoproteins as immunogens have been developed for prophylactic vaccination against HCV. However, the ideal mode of processing and presenting these immunogens for effective vaccination has yet to be determined. We used our recently described vaccine candidate based on full-length HCV E1 or E2 glycoproteins fused to the heterologous hepatitis B virus S envelope protein to compare the use of the E1 and E2 proteins as separate immunogens with their use as the E1E2 heterodimer, in terms of immunogenetic potential and the capacity to induce neutralizing antibodies. The specific anti-E1 and anti-E2 antibody responses induced in animals immunized with vaccine particles harboring the heterodimer were profoundly impaired with respect to those in animals immunized with particles harboring E1 and E2 separately. Moreover, the anti-E1 and anti-E2 antibodies had additive neutralizing properties that increase the cross-neutralization of heterologous strains of various HCV genotypes, highlighting the importance of including both E1 and E2 in the vaccine for an effective vaccination strategy. Our study has important implications for the optimization of HCV vaccination strategies based on HCV envelope proteins, regardless of the platform used to present these proteins to the immune system. PMID:26966906

  16. Hepatitis C Virus E1 and E2 Proteins Used as Separate Immunogens Induce Neutralizing Antibodies with Additive Properties.

    Directory of Open Access Journals (Sweden)

    Elodie Beaumont

    Full Text Available Various strategies involving the use of hepatitis C virus (HCV E1 and E2 envelope glycoproteins as immunogens have been developed for prophylactic vaccination against HCV. However, the ideal mode of processing and presenting these immunogens for effective vaccination has yet to be determined. We used our recently described vaccine candidate based on full-length HCV E1 or E2 glycoproteins fused to the heterologous hepatitis B virus S envelope protein to compare the use of the E1 and E2 proteins as separate immunogens with their use as the E1E2 heterodimer, in terms of immunogenetic potential and the capacity to induce neutralizing antibodies. The specific anti-E1 and anti-E2 antibody responses induced in animals immunized with vaccine particles harboring the heterodimer were profoundly impaired with respect to those in animals immunized with particles harboring E1 and E2 separately. Moreover, the anti-E1 and anti-E2 antibodies had additive neutralizing properties that increase the cross-neutralization of heterologous strains of various HCV genotypes, highlighting the importance of including both E1 and E2 in the vaccine for an effective vaccination strategy. Our study has important implications for the optimization of HCV vaccination strategies based on HCV envelope proteins, regardless of the platform used to present these proteins to the immune system.

  17. Toward the Identification of Two Glycoproteins Involved in the Stomatal Deregulation of Downy Mildew-Infected Grapevine Leaves.

    Science.gov (United States)

    Guillier, Christelle; Gamm, Magdalena; Lucchi, Géraldine; Truntzer, Caroline; Pecqueur, Delphine; Ducoroy, Patrick; Adrian, Marielle; Héloir, Marie-Claire

    2015-11-01

    Stomata remain abnormally opened and unresponsive to abscisic acid in grapevine leaves infected by downy mildew. This deregulation occurs from 3 days postinoculation and increases concomitantly with leaf colonization by the pathogen. Using epidermal peels, we demonstrated that the active compound involved in this deregulation is located in the apoplast. Biochemical assays showed that the active compound present in the apoplastic fluids isolated from Plasmopara viticola-infected grapevine leaves (IAF) is a CysCys bridge-independent, thermostable and glycosylated protein. Fractionation guided assays based on chromatography coupled to stomatal response and proteomic analysis allowed the identification of both plant and pathogen proteins in the active fraction obtained from IAF. Further in silico analysis and discriminant filtrations based on the comparison between predictions and experimental indications lead to the identification of two Vitis vinifera proteins as candidates for the observed stomatal deregulation.

  18. EGF Receptor-Dependent Mechanism May be Involved in the Tamm–Horsfall Glycoprotein-Enhanced PMN Phagocytosis via Activating Rho Family and MAPK Signaling Pathway

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    Ko-Jen Li

    2014-01-01

    Full Text Available Our previous studies showed that urinary Tamm–Horsfall glycoprotein (THP potently enhanced polymorphonuclear neutrophil (PMN phagocytosis. However, the domain structure(s, signaling pathway and the intracellular events responsible for THP-enhanced PMN phagocytosis remain to be elucidated. THP was purified from normal human urine. The human promyelocytic leukemia cell line HL-60 was induced to differentiate into PMNs by all-trans retinoid acid. Pretreatment with different MAPK and PI3K inhibitors was used to delineate signaling pathways in THP-enhanced PMN phagocytosis. Phosphorylation of molecules responsible for PMN phagocytosis induced by bacterial lipopolysaccharide (LPS, THP, or human recombinant epidermal growth factor (EGF was evaluated by western blot. A p38 MAPK inhibitor, SB203580, effectively inhibited both spontaneous and LPS- and THP-induced PMN phagocytosis. Both THP and LPS enhanced the expression of the Rho family proteins Cdc42 and Rac that may lead to F-actin re-arrangement. Further studies suggested that THP and EGF enhance PMN and differentiated HL-60 cell phagocytosis in a similar pattern. Furthermore, the EGF receptor inhibitor GW2974 significantly suppressed THP- and EGF-enhanced PMN phagocytosis and p38 and ERK1/2 phosphorylation in differentiated HL-60 cells. We conclude that EGF receptor-dependent signaling may be involved in THP-enhanced PMN phagocytosis by activating Rho family and MAP kinase.

  19. The Hinge Region of Bovine Zona Pellucida Glycoprotein ZP3 Is Involved in the Formation of the Sperm-Binding Active ZP3/ZP4 Complex.

    Science.gov (United States)

    Suzuki, Kaori; Tatebe, Nanami; Kojima, Sayuri; Hamano, Ayumi; Orita, Misaki; Yonezawa, Naoto

    2015-01-01

    The zona pellucida (ZP) surrounds the mammalian oocyte and mediates species-selective sperm-oocyte interactions. Bovine ZP consists of glycoproteins ZP2, ZP3, and ZP4. Neither ZP3 nor ZP4 alone shows inhibitory activity for the binding of sperm to the ZP; however, this activity is seen with the ZP3/ZP4 heterocomplex. Here, we constructed a series of bovine ZP3 mutants to identify the ZP4-binding site on ZP3. Each ZP3 mutant was co-expressed with ZP4 using a baculovirus-Sf9 cell expression system and examined for interaction with ZP4 as well as inhibitory activity for sperm-ZP binding. N-terminal fragment Arg-32 to Arg-160 of ZP3 interacted with ZP4 and inhibited sperm-ZP binding, whereas fragment Arg-32 to Thr-155 showed much weaker interaction with ZP4. Mutation of N-glycosylated Asn-146 to Asp in the N-terminal fragment Arg-32 to Glu-178 of ZP3 did not interrupt the interaction of this fragment with ZP4, but it did reduce the inhibitory activity of the complex for sperm-ZP binding. In contrast, mutation of N-glycosylated Asn-124 to Asp did not significantly reduce the activity. Taken together, these results suggest that one of the ZP4 binding sites exists in the flexible hinge region of ZP3 and that the N-glycosylation in this region is involved in the sperm binding.

  20. The Hinge Region of Bovine Zona Pellucida Glycoprotein ZP3 Is Involved in the Formation of the Sperm-Binding Active ZP3/ZP4 Complex

    Directory of Open Access Journals (Sweden)

    Kaori Suzuki

    2015-11-01

    Full Text Available The zona pellucida (ZP surrounds the mammalian oocyte and mediates species-selective sperm-oocyte interactions. Bovine ZP consists of glycoproteins ZP2, ZP3, and ZP4. Neither ZP3 nor ZP4 alone shows inhibitory activity for the binding of sperm to the ZP; however, this activity is seen with the ZP3/ZP4 heterocomplex. Here, we constructed a series of bovine ZP3 mutants to identify the ZP4-binding site on ZP3. Each ZP3 mutant was co-expressed with ZP4 using a baculovirus-Sf9 cell expression system and examined for interaction with ZP4 as well as inhibitory activity for sperm-ZP binding. N-terminal fragment Arg-32 to Arg-160 of ZP3 interacted with ZP4 and inhibited sperm-ZP binding, whereas fragment Arg-32 to Thr-155 showed much weaker interaction with ZP4. Mutation of N-glycosylated Asn-146 to Asp in the N-terminal fragment Arg-32 to Glu-178 of ZP3 did not interrupt the interaction of this fragment with ZP4, but it did reduce the inhibitory activity of the complex for sperm-ZP binding. In contrast, mutation of N-glycosylated Asn-124 to Asp did not significantly reduce the activity. Taken together, these results suggest that one of the ZP4 binding sites exists in the flexible hinge region of ZP3 and that the N-glycosylation in this region is involved in the sperm binding.

  1. Involvement of cytochrome P450 3A4 and P-glycoprotein in first-pass intestinal extraction of omeprazole in rabbits

    Institute of Scientific and Technical Information of China (English)

    Hai-ming FANG; Jian-ming XU; Qiao MEI; Lei DIAO; Mo-li CHEN; Juan JIN; Xin-hua XU

    2009-01-01

    Aim: To quantitatively evaluate in vivo first-pass intestinal extraction of omeprazole and to investigate the possible involvement of cytochrome P450 3A4 (CYP3A4) and P-glycoprotein (P-gp) in this process in rabbits.Methods: Pharmacokinetic parameters were examined after intraduodenal (id), intraportal venous (ipv), and intravenous (iv) administration of omeprazole at various doses to intestinal and vascular access-ported rabbits. Extraction ratios in the liver and intestinal tract were determined from the area under the plasma concentration-time curve (AUC). In addition, omeprazole was administered by id or iv to rabbits alone or 30 min after the id administration of CYP3A4 or P-gp inhibitors (ketoconazole or verapamil, respectively). Results: Pharmacokinetic parameters of omeprazole were dose-dependent after id, ipv, and iv administration at various doses. After id administration of 3 mg/kg omeprazole, the hepatic and intestinal extraction ratio was 57.18%±2.73% and 54.94%±1.85%, while the value was 59.29%±3.14% and 54.20%±1.53% after given 6 mg/kg, respectively. Compared with the control group, the presence of ketoconazole (60 mg/kg) or verapamil (9 mg/kg) significantly increased the area under the plasma concentration time curve (AUC) and the peak concentration (C_(max)) of id-administered omeprazole, while it had no significant effect on omeprazole administered by iv. Conclusion: Oral omeprazole undergoes marked extraction in the small intestine, and increased bioavailability of the drug after id administration of ketoconazole and verapamil suggests that this increase results from inhibition of CYP3A4 and P-gp function in the intestine rather than the liver.

  2. Mechanisms involved in the cytotoxic action of Brazilian propolis and caffeic acid against HEp-2 cells and modulation of P-glycoprotein activity.

    Science.gov (United States)

    da Silva, Lívia M; Frión-Herrera, Yahima; Bartolomeu, Ariane R; Gorgulho, Carolina Mendonça; Sforcin, José M

    2017-08-04

    The effects of propolis and phenolic compounds (caffeic acid - Caf; dihydrocinnamic acid - Cin; p-coumaric acid - Cou) in the same quantity found in our propolis sample were investigated on human laryngeal epidermoid carcinoma (HEp-2) cells. Cell viability, apoptosis/necrosis and cell cycle arrest, P53 and CASPASE-3 gene expression, generation of reactive oxygen species (ROS) and the ability of propolis to induce doxorubicin (DOX) efflux using a P-glycoprotein (P-gp) inhibitor (verapamil) were assayed. Propolis exerted a cytotoxic effect on HEp-2 cells, whereas isolated compounds had no effect on cell viability. Higher concentrations were tested and Caf induced late apoptosis or necrosis in HEp-2 cells, while propolis induced apoptosis, both probably due to ROS generation. P53 expression was downregulated by propolis but not by Caf. CASPASE-3 expression was correlated with induction of both early and late apoptosis, with both propolis and Caf alone upregulating its expression. Propolis induced cell cycle arrest at G2/M phase and Caf at S phase. Propolis but not Caf may act as a P-gp inhibitor by modulating P-gp activity and inhibiting DOX efflux. Propolis exerted cytotoxic effects on HEp-2 cells, and the mechanisms are discussed, showing its potential as an antitumour drug. © 2017 Royal Pharmaceutical Society.

  3. The absorption enhancement of norisoboldine in the duodenum of adjuvant-induced arthritis rats involves the impairment of P-glycoprotein.

    Science.gov (United States)

    Duan, Cong; Guo, Jiao-Mei; Dai, Yue; Xia, Yu-Feng

    2017-01-01

    Lindera aggregata (Sims) Kosterm root has been used in traditional Chinese medicine for the treatment of rheumatism palsy, dyspepsia and frequent urination for a long time. Norisoboldine, the main active constituent of this herb drug, possesses outstanding anti-arthritis activity. However, the in vivo disposition of norisoboldine is known to a limited extent, especially under the pathological condition of rheumatoid arthritis (RA). The aim of this study is to investigate whether and how the absorption of norisoboldine is altered in adjuvant-induced arthritis (AIA) rats. Comparative studies of the intestinal absorption of norisoboldine in normal and AIA rats at different pathological stages of the arthritis were performed using in situ single-pass intestinal perfusion, and the effects of an inhibitor of efflux proteins were also investigated. Norisoboldine was shown to be a substrate of P-glycoprotein (P-gp), as P-gp inhibitor verapamil markedly increased the permeability coefficient (Peff ) of norisoboldine by 88% in the intestine of normal rats. Compared with normal rats, AIA rats displayed increased Peff values of norisoboldine by 84% and 86% on day 5 and day 10 after the appearance of the secondary response of arthritis, respectively. Verapamil could eliminate the difference of intestinal absorption of norisoboldine between normal and AIA rats. Further studies showed that impaired expression and activity of P-gp in AIA rats play a decisive role in the absorption enhancement of norisoboldine. Notably, the impairment of P-gp function positively correlated with the severity of arthritis. Copyright © 2016 John Wiley & Sons, Ltd.

  4. Structure of a Pestivirus Envelope Glycoprotein E2 Clarifies Its Role in Cell Entry

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    Kamel El Omari

    2013-01-01

    Full Text Available Enveloped viruses have developed various adroit mechanisms to invade their host cells. This process requires one or more viral envelope glycoprotein to achieve cell attachment and membrane fusion. Members of the Flaviviridae such as flaviviruses possess only one envelope glycoprotein, E, whereas pestiviruses and hepacivirus encode two glycoproteins, E1 and E2. Although E2 is involved in cell attachment, it has been unclear which protein is responsible for membrane fusion. We report the crystal structures of the homodimeric glycoprotein E2 from the pestivirus bovine viral diarrhea virus 1 (BVDV1 at both neutral and low pH. Unexpectedly, BVDV1 E2 does not have a class II fusion protein fold, and at low pH the N-terminal domain is disordered, similarly to the intermediate postfusion state of E2 from sindbis virus, an alphavirus. Our results suggest that the pestivirus and possibly the hepacivirus fusion machinery are unlike any previously observed.

  5. Fatty Acid Synthase and Hormone-sensitive Lipase Expression in Liver Are Involved in Zinc-α2-glycoprotein-induced Body Fat Loss in Obese Mice

    Institute of Scientific and Technical Information of China (English)

    Feng-ying Gong; Jie-ying Deng; Hui-juan Zhu; Hui Pan; Lin-jie Wang; Hong-bo Yang

    2010-01-01

    Objective To explore the effects of zinc-a2-glycoprotein (ZAG) on body weight and body fat in high-fat-diet (HFD)-induced obesity in mice and the possible mechanism.Methods Thirty-six male mice were fed with standard food (SF) (n=9) and HFD (n=27), respec-tively. Five weeks later, 9 mice fed with HFD were subjected to ZAG expression plasmid DNA transfection by liposome transfection method, and another 9 mice to negative control plasmid transfection. Two weeks later, serum ZAG level in the mice was assayed by Western blot, and the effects of ZAG over-expression on body weight, body fat, serum biochemical indexes, and adipose tissue of obese mice were evaluated. The mRNA expressions of fatty acid synthase (FAS) and hormone-sensitive lipase (HSL) in liver tissue were de-termined by reverse transcription-polymerase chain reaction.Results Serum ZAG level significantly lowered in simple HFD-fed mice in comparison to SF-fed mice (0.51±0.10 AU vs. 0.75±0.07 AU, P<0.01). Further statistical analysis demonstrated that ZAG level was negatively correlated with body weight (r =-0.56, P<0.001), epididymal fat mass (r=-0. 67, P<0.001), percentage of epididymal fat (r=-0.65, P<0.001 ), and increased weight (r=-0.57, P<0.001) in simple SF-and HFD-fed mice. ZAG over-expression in obese mice reduced body weight and the percentage of epididy-mal fat. Furthermore, FAS mRNA expression decreased (P<0.01) and HSL mRNA expression increased (P<0.001) in the liver in ZAG over-expressing mice.Conclusions ZAG is closely related to obesity. Serum ZAG level is inversely correlated with body weight and percentage of body fat. The action of ZAG is associated with reduced FAS expression and in-creased HSL expression in the liver of obese mice.

  6. Neutralization of feline immunodeficiency virus by polyclonal cat antibody: Simultaneous involvement of hypervariable regions 4 and 5 of the surface glycoprotein.

    NARCIS (Netherlands)

    C.H.J. Siebelink (Kees); W. Huisman (Willem); J.A. Karlas (Jos); G.F. Rimmelzwaan (Guus); M.L. Bosch (Marnix); A.D.M.E. Osterhaus (Albert)

    1995-01-01

    textabstractSites involved in antibody-mediated neutralization of feline immunodeficiency virus were mapped by reciprocal exchange of envelope fragments or amino acids between molecular clones of feline immunodeficiency virus with different susceptibilities to neutralization by a polyclonal cat seru

  7. Glycoproteins: Occurrence and Significance

    Science.gov (United States)

    Wittmann, Valentin

    Protein glycosylation is regarded as the most complex form of post-translational modification leading to a heterogeneous expression of glycoproteins as mixtures of glycoforms. This chapter describes the structure and occurrence of glycoproteins with respect to their glycan chains. Discussed are different carbohydrate-peptide linkages including GPI anchors, common structures of N- and O-glycans, and the structure of glycosaminoglycans contained in proteoglycans. Also covered are the bacterial cell wall polymer peptidoglycan and the glycopeptide antibiotics of the vancomycin group. Properties and functions of the glycans contained in glycoproteins are dealt with in the next chapter of this book.

  8. Structure of a trimeric variant of the Epstein–Barr virus glycoprotein B

    OpenAIRE

    2009-01-01

    Epstein–Barr virus (EBV) is a herpesvirus that is associated with development of malignancies of lymphoid tissue. EBV infections are life-long and occur in >90% of the population. Herpesviruses enter host cells in a process that involves fusion of viral and cellular membranes. The fusion apparatus is comprised of envelope glycoprotein B (gB) and a heterodimeric complex made of glycoproteins H and L. Glycoprotein B is the most conserved envelope glycoprotein in human herpesviruses, and the str...

  9. Glycoprotein biosynthesis in calf kidney. Glycoprotein sialyltransferase activities towards serum glycoproteins and calf Tamm-Horsfall glycoprotein.

    Science.gov (United States)

    van Dijk, W; Lasthuis, A M; van den Eijnden, D H

    1979-04-18

    CMP-AcNeu:glycoprotein sialyltransltransltransltransltransferase of calf kidney cortex was characterized using serum glycoproteins and Tamm-Horsfall glycoprotein, obtained from calf urine, as acceptors. Native calf Tamm-Horsfall glycoprotein showed the best acceptor properties, followed by desialylated calf fetuin and desialylated human alpha 1-acid glycoprotein exhibiting V values of, respectively, 114, 63 and 41 nmol/h per g wet wt. of kidney cortex and Km values of 0.12, 0.16 and 0.26 mM glycoprotein acceptor. Desialylated ovine submaxillary mucine appeared to be a very poor acceptor. Tamm-Horsfall glycoprotein sialyltransferase could be distinguished from serum glycoprotein sialyltransferase by competition studies. In addition the two glycoprotein sialyltransferase activities showed different distributions over the three regions of the calf kidney: the ratios of the Tamm-Horsfall to serum glycoprotein sialyltransferase activities decreased from 3.3 in the cortex to 0.8 and 0.4 in the medulla and the papilla, respectively. It was concluded that in calf kidney at least two different sialyltransferases exist. The high cortical Tamm-Horsfall glycoprotein sialyltransferases activity corresponds markedly to the origin of the urinary Tamm-Horsfall glycoprotein, namely the distal part of the kidney tubule. Inactivation of glycoprotein sialyltransferase activity by preincubation at various temperatures and during storage at 0 degree C, could be reduced by the addition of CMP-AcNeu. The possible relevance towards the in vivo sialylation of this finding is discussed.

  10. Purification and application of C-terminally truncated hepatitis C virus E1 proteins expressed in Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    Jing Liu; Li-Xin Zhu; Yu-Ying Kong; Guang-Di Li; Yuan Wang

    2005-01-01

    AIM: To explore the possibility of expressing hepatitis C virus (HCV) envelope protein 1 (E1) in Escherichia coli(E.coli)and to test the purified recombinant E1 proteins for clinical and research applications. METHODS: C-terminally trunczated E1 fragments were expressed in E. coli as hexa-histidine-tagged fusion proteins. The expression products were purified under denaturing conditions using immobilized-metal affinity chromatography. Purified E1 proteins were used to immunize rabbits. Rabbit anti-sera thus obtained were reacted with both E. coli- and mammalian cell-expressed E1 glycoproteins as detected by Western blot.RESULTS: Full-length E1 protein proved difficult to express in E. coli. C-terminally truncated E1 was successfully expressed in E. coli as hexa-histidine-tagged recombinant fusion protein and was purified under denaturing conditions on Ni2+-NTA agarose. Rabbit anti-sera raised against purified recombinant E1 specifically reacted with mammalian cell-expressed E1 giycoproteins in Western blot. Furthermore, E. coli-derived E1 protein was able to detect animal antibodies elicited by E1-based DNA immunization.CONCLUSION: These results demonstrate that the prokaryotically expressed E1 proteins share identical epitopes with eukaryotically expressed E1 glycoprotein. The E. coli-derived E1 proteins and corresponding antisera can become useful tools in anti-HCV vaccine research.

  11. HIV-1 envelope glycoprotein

    Energy Technology Data Exchange (ETDEWEB)

    Caulfield, Michael; Cupo, Albert; Dean, Hansi; Hoffenberg, Simon; King, C. Richter; Klasse, P. J.; Marozsan, Andre; Moore, John P.; Sanders, Rogier W.; Ward, Andrew; Wilson, Ian; Julien, Jean-Philippe

    2017-08-22

    The present application relates to novel HIV-1 envelope glycoproteins, which may be utilized as HIV-1 vaccine immunogens, and antigens for crystallization, electron microscopy and other biophysical, biochemical and immunological studies for the identification of broad neutralizing antibodies. The present invention encompasses the preparation and purification of immunogenic compositions, which are formulated into the vaccines of the present invention.

  12. CYP2E1 autoantibodies in liver diseases

    Science.gov (United States)

    Sutti, Salvatore; Rigamonti, Cristina; Vidali, Matteo; Albano, Emanuele

    2014-01-01

    Autoimmune reactions involving cytochrome P4502E1 (CYP2E1) are a feature of idiosyncratic liver injury induced by halogenated hydrocarbons and isoniazid, but are also detectable in about one third of the patients with advanced alcoholic liver disease (ALD) and chronic hepatitis C (CHC). In these latter the presence of anti-CYP2E1 auto-antibodies is an independent predictor of extensive necro-inflammation and fibrosis and worsens the recurrence of hepatitis following liver transplantation, indicating that CYP2E1-directed autoimmunity can contribute to hepatic injury. The molecular characterization of the antigens recognized by anti-CYP2E1 auto-antibodies in ALD and CHC has shown that the targeted conformational epitopes are located in close proximity on the molecular surface. Furthermore, these epitopes can be recognized on CYP2E1 expressed on hepatocyte plasma membranes where they can trigger antibody-mediated cytotoxicity. This does not exclude that T cell-mediated responses against CYP2E1 might also be involved in causing hepatocyte damage. CYP2E1 structural modifications by reactive metabolites and molecular mimicry represent important factors in the breaking of self-tolerance against CYP2E1 in, respectively, ALD and CHC. However, genetic or acquired interferences with the mechanisms controlling the homeostasis of the immune system are also likely to contribute. More studies are needed to better characterize the impact of anti-CYP2E1 autoimmunity in liver diseases particularly in relation to the fact that common metabolic alterations such as obesity and diabetes stimulates hepatic CYP2E1 expression. PMID:25462068

  13. Functional processing and secretion of Chikungunya virus E1 and E2 glycoproteins in insect cells

    NARCIS (Netherlands)

    S.W. Metz (Stefan); C. Geertsema (Corinne); B.E.E. Martina (Byron); P. Andrade (Paulina); J.G.M. Heldens; M.M. van Oers (Monique); J.M. Vlak (Just); G.P. Pijlman (Gorben)

    2011-01-01

    textabstractBackground: Chikungunya virus (CHIKV) is a mosquito-borne, arthrogenic Alphavirus that causes large epidemics in Africa, South-East Asia and India. Recently, CHIKV has been transmitted to humans in Southern Europe by invading and now established Asian tiger mosquitoes. To study the proce

  14. Functional processing and secretion of Chikungunya virus E1 and E2 glycoproteins in insect cells

    NARCIS (Netherlands)

    Metz, S.W.H.; Geertsema, C.; Martina, Byron E.; Andrade, Paulina; Heldens, J.; Oers, van M.M.; Goldbach, R.W.; Vlak, J.M.; Pijlman, G.P.

    2011-01-01

    Background - Chikungunya virus (CHIKV) is a mosquito-borne, arthrogenic Alphavirus that causes large epidemics in Africa, South-East Asia and India. Recently, CHIKV has been transmitted to humans in Southern Europe by invading and now established Asian tiger mosquitoes. To study the processing of en

  15. Functional processing and secretion of Chikungunya virus E1 and E2 glycoproteins in insect cells

    NARCIS (Netherlands)

    S.W. Metz (Stefan); C. Geertsema (Corinne); B.E.E. Martina (Byron); P. Andrade (Paulina); J.G.M. Heldens; M.M. van Oers (Monique); J.M. Vlak (Just); G.P. Pijlman (Gorben)

    2011-01-01

    textabstractBackground: Chikungunya virus (CHIKV) is a mosquito-borne, arthrogenic Alphavirus that causes large epidemics in Africa, South-East Asia and India. Recently, CHIKV has been transmitted to humans in Southern Europe by invading and now established Asian tiger mosquitoes. To study the proce

  16. Herpesvirus glycoproteins undergo multiple antigenic changes before membrane fusion.

    Directory of Open Access Journals (Sweden)

    Daniel L Glauser

    Full Text Available Herpesvirus entry is a complicated process involving multiple virion glycoproteins and culminating in membrane fusion. Glycoprotein conformation changes are likely to play key roles. Studies of recombinant glycoproteins have revealed some structural features of the virion fusion machinery. However, how the virion glycoproteins change during infection remains unclear. Here using conformation-specific monoclonal antibodies we show in situ that each component of the Murid Herpesvirus-4 (MuHV-4 entry machinery--gB, gH/gL and gp150--changes in antigenicity before tegument protein release begins. Further changes then occurred upon actual membrane fusion. Thus virions revealed their final fusogenic form only in late endosomes. The substantial antigenic differences between this form and that of extracellular virions suggested that antibodies have only a limited opportunity to block virion membrane fusion.

  17. Cell-based analysis of Chikungunya virus E1 protein in membrane fusion

    Directory of Open Access Journals (Sweden)

    Kuo Szu-Cheng

    2012-04-01

    Full Text Available Abstract Background Chikungunya fever is a pandemic disease caused by the mosquito-borne Chikungunya virus (CHIKV. E1 glycoprotein mediation of viral membrane fusion during CHIKV infection is a crucial step in the release of viral genome into the host cytoplasm for replication. How the E1 structure determines membrane fusion and whether other CHIKV structural proteins participate in E1 fusion activity remain largely unexplored. Methods A bicistronic baculovirus expression system to produce recombinant baculoviruses for cell-based assay was used. Sf21 insect cells infected by recombinant baculoviruses bearing wild type or single-amino-acid substitution of CHIKV E1 and EGFP (enhanced green fluorescence protein were employed to investigate the roles of four E1 amino acid residues (G91, V178, A226, and H230 in membrane fusion activity. Results Western blot analysis revealed that the E1 expression level and surface features in wild type and mutant substituted cells were similar. However, cell fusion assay found that those cells infected by CHIKV E1-H230A mutant baculovirus showed little fusion activity, and those bearing CHIKV E1-G91D mutant completely lost the ability to induce cell-cell fusion. Cells infected by recombinant baculoviruses of CHIKV E1-A226V and E1-V178A mutants exhibited the same membrane fusion capability as wild type. Although the E1 expression level of cells bearing monomeric-E1-based constructs (expressing E1 only was greater than that of cells bearing 26S-based constructs (expressing all structural proteins, the sizes of syncytial cells induced by infection of baculoviruses containing 26S-based constructs were larger than those from infections having monomeric-E1 constructs, suggesting that other viral structure proteins participate or regulate E1 fusion activity. Furthermore, membrane fusion in cells infected by baculovirus bearing the A226V mutation constructs exhibited increased cholesterol-dependences and lower pH thresholds

  18. Isolation of coronavirus envelope glycoproteins and interaction with the viral nucleocapsid.

    OpenAIRE

    Sturman, L S; Holmes, K V; Behnke, J.

    1980-01-01

    The two envelope glycoproteins and the viral nucleocapsid of the coronavirus A59 were isolated by solubilization of the viral membrane with Nonidet P-40 at 4 degrees C followed by sucrose density gradient sedimentation. Isolated E2 consisted of rosettes of peplomers, whereas E1, the membrane glycoprotein, was irregular and amorphous. Under certain conditions significant interactions occurred between components of Nonidet P-40-disrupted virions. Incubation of the Nonidet P-40-disrupted virus a...

  19. Signal peptide replacements enhance expression and secretion of hepatitis C virus envelope glycoproteins

    Institute of Scientific and Technical Information of China (English)

    Bo Wen; Yao Deng; Jie Guan; Weizheng Yan; Yue Wang; Wenjie Tan; Jimin Gao

    2011-01-01

    A large number of researches focused on glycoproteins E1 and E2 of hepatitis C virus (HCV) aimed at the develop-ment of anti-HCV vaccines and inhibitors. Enhancement of E1/E2 expression and secretion is critical for the charac-terization of these glycoproteins and thus for subunit vaccine development. In this study, we designed and syn-thesized three signal peptide sequences based on onlineprograms SignalP, TargetP, and PSORT, then removed and replaced the signal peptide preceding E1/E2 by over-lapping the polymerase chain reaction method. We assessed the effect of this alteration on E1/E2 expression and secretion in mammalian cells, using western blot analysis, dot blot, and Galanthus nivalis agglutinin iectin capture enzyme immunoassay. Replacing the peptides pre-ceding E1 and E2 with the signal peptides of the tissue plasminogen activator and Gaussia luciferase resulted in maximum enhancement of E1/E2 expression and secretion of E1 in mammalian cells, without altering glycosylation.Such an advance would help to facilitate both the research of E1/E2 biology and the development of an effective HCV subunit vaccine. The strategy used in this study could be applied to the expression and production of other glyco-proteins in mammalian ceil line-based systems.

  20. Envelope glycoprotein of arenaviruses.

    Science.gov (United States)

    Burri, Dominique J; da Palma, Joel Ramos; Kunz, Stefan; Pasquato, Antonella

    2012-10-17

    Arenaviruses include lethal human pathogens which pose serious public health threats. So far, no FDA approved vaccines are available against arenavirus infections, and therapeutic options are limited, making the identification of novel drug targets for the development of efficacious therapeutics an urgent need. Arenaviruses are comprised of two RNA genome segments and four proteins, the polymerase L, the envelope glycoprotein GP, the matrix protein Z, and the nucleoprotein NP. A crucial step in the arenavirus life-cycle is the biosynthesis and maturation of the GP precursor (GPC) by cellular signal peptidases and the cellular enzyme Subtilisin Kexin Isozyme-1 (SKI-1)/Site-1 Protease (S1P) yielding a tripartite mature GP complex formed by GP1/GP2 and a stable signal peptide (SSP). GPC cleavage by SKI-1/S1P is crucial for fusion competence and incorporation of mature GP into nascent budding virion particles. In a first part of our review, we cover basic aspects and newer developments in the biosynthesis of arenavirus GP and its molecular interaction with SKI-1/S1P. A second part will then highlight the potential of SKI-1/S1P-mediated processing of arenavirus GPC as a novel target for therapeutic intervention to combat human pathogenic arenaviruses.

  1. Envelope Glycoprotein of Arenaviruses

    Directory of Open Access Journals (Sweden)

    Antonella Pasquato

    2012-10-01

    Full Text Available Arenaviruses include lethal human pathogens which pose serious public health threats. So far, no FDA approved vaccines are available against arenavirus infections, and therapeutic options are limited, making the identification of novel drug targets for the development of efficacious therapeutics an urgent need. Arenaviruses are comprised of two RNA genome segments and four proteins, the polymerase L, the envelope glycoprotein GP, the matrix protein Z, and the nucleoprotein NP. A crucial step in the arenavirus life-cycle is the biosynthesis and maturation of the GP precursor (GPC by cellular signal peptidases and the cellular enzyme Subtilisin Kexin Isozyme-1 (SKI-1/Site-1 Protease (S1P yielding a tripartite mature GP complex formed by GP1/GP2 and a stable signal peptide (SSP. GPC cleavage by SKI-1/S1P is crucial for fusion competence and incorporation of mature GP into nascent budding virion particles. In a first part of our review, we cover basic aspects and newer developments in the biosynthesis of arenavirus GP and its molecular interaction with SKI-1/S1P. A second part will then highlight the potential of SKI-1/S1P-mediated processing of arenavirus GPC as a novel target for therapeutic intervention to combat human pathogenic arenaviruses.

  2. Proteomic fingerprinting of N-linked glycoproteins involved in hepatocellular carcinoma%肝细胞癌中差异表达 N-连接糖蛋白的分析鉴定

    Institute of Scientific and Technical Information of China (English)

    马瑾; 齐义军; 刘瑞敏; 王明; 张天; 朱晗; 马远方

    2014-01-01

    目的:分析鉴定与肝细胞癌( HCC)发生发展相关的差异表达的N-连接糖蛋白。方法应用刀豆蛋白凝集素(ConA)、晶状体凝集素(LCH)和雪花凝集素(GNA)组成的亲合层析柱富集10对HCC和癌旁非癌组织中N-连接糖蛋白、二维电泳(2DE)比较分析差异表达的蛋白质点、串联质谱鉴定差异表达蛋白,Western blotting 验证人羧酸酯酶1(hCE1)、触珠蛋白(HP)及组织蛋白酶D(CD)的差异表达;体外侵袭实验检测CD表达沉默后对HCC的侵袭力影响。结果质谱、生物信息学等技术鉴定了28个与HCC相关的差异表达蛋白( HCC中高表达和低表达的蛋白均为14个),Western blotting验证hCE1、HP在HCC中明显低表达,组织蛋白酶D前体( pCD)在HCC中高表达;而ConA亲和层析柱富集的ConA-CD在HCC中显著高表达。 CD-siRNA介导的CD表达沉默能够显著降低肝癌细胞系SNU449、SNU473的体外侵袭能力。结论 HP、hCE1蛋白表达变化和CD N-糖链变异可能参与了HCC发生发展过程。%Objective To identify differentially expressed N-linked glycoproteins between hepatocellular carcinoma ( HCC) and adjacent non-tumorous liver tissues .Methods N-linked glycoproteome was extracted by multi-lectin affinity chromatography comprising concanavalin A (ConA), lentil lectin (LCH), and snowdrop lectin (GNA) and subsequently subjected to two-dimensional electrophoresis ( 2DE ) and mass spectrometry ( MS ) for identification of differential glycoproteins between 10 pairs of HCC and adjacent non-cancer tissue .Western blotting was used to verify different expression of human liver carboxylesterase 1 (hCE1), haptoglobin (HP)and cathepsin D (CD).Invasion potential in vitro was examined after si-RNA mediated CD gene scilencing .Results LC-ESI-MS/MS identified a total of 28 differentially expressed glycoproteins (14 up-regulation and 14 down-regulated).Western blotting detected consistent down

  3. The equine herpesvirus 1 glycoprotein gp21/22a, the herpes simplex virus type 1 gM homolog, is involved in virus penetration and cell-to-cell spread of virions.

    Science.gov (United States)

    Osterrieder, N; Neubauer, A; Brandmuller, C; Braun, B; Kaaden, O R; Baines, J D

    1996-06-01

    Experiments to analyze the function of the equine herpesvirus 1 (EHV-1) glycoprotein gM homolog were conducted. To this end, an Rk13 cell line (TCgM) that stably expressed EHV-1 gM was constructed. Proteins with apparent M(r)s of 46,000 to 48,000 and 50,000 to 55,000 were detected in TCgM cells with specific anti-gM antibodies, and the gM protein pattern was indistinguishable from that in cells infected with EHV-1 strain RacL11. A viral mutant (L11deltagM) bearing an Escherichia coli lacZ gene inserted into the EHV-1 strain RacL11 gM gene (open reading frame 52) was purified, and cells infected with L11deltagM did not contain detectable gM. L11deltagM exhibited approximately 100-fold lower titers and a more than 2-fold reduction in plaque size relative to wild-type EHV-1 when grown and titrated on noncomplementing cells. Viral titers were reduced only 10-fold when L11deltagM was grown on the complementing cell line TCgM and titrated on noncomplementing cells. L11deltagM also exhibited slower penetration kinetics compared with those of the parental EHV-1 RacL11. It is concluded that EHV-1 gM plays important roles in the penetration of virus into the target cell and in spread of EHV-1 from cell to cell.

  4. Retroviral Env Glycoprotein Trafficking and Incorporation into Virions

    Directory of Open Access Journals (Sweden)

    Tsutomu Murakami

    2012-01-01

    Full Text Available Together with the Gag protein, the Env glycoprotein is a major retroviral structural protein and is essential for forming infectious virus particles. Env is synthesized, processed, and transported to certain microdomains at the plasma membrane and takes advantage of the same host machinery for its trafficking as that used by cellular glycoproteins. Incorporation of Env into progeny virions is probably mediated by the interaction between Env and Gag, in some cases with the additional involvement of certain host factors. Although several general models have been proposed to explain the incorporation of retroviral Env glycoproteins into virions, the actual mechanism for this process is still unclear, partly because structural data on the Env protein cytoplasmic tail is lacking. This paper presents the current understanding of the synthesis, trafficking, and virion incorporation of retroviral Env proteins.

  5. Di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone (Dp44mT) overcomes multidrug resistance by a novel mechanism involving the hijacking of lysosomal P-glycoprotein (Pgp).

    Science.gov (United States)

    Jansson, Patric J; Yamagishi, Tetsuo; Arvind, Akanksha; Seebacher, Nicole; Gutierrez, Elaine; Stacy, Alexandra; Maleki, Sanaz; Sharp, Danae; Sahni, Sumit; Richardson, Des R

    2015-04-10

    Multidrug resistance (MDR) is a major obstacle in cancer treatment. More than half of human cancers express multidrug-resistant P-glycoprotein (Pgp), which correlates with a poor prognosis. Intriguingly, through an unknown mechanism, some drugs have greater activity in drug-resistant tumor cells than their drug-sensitive counterparts. Herein, we investigate how the novel anti-tumor agent di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone (Dp44mT) overcomes MDR. Four different cell types were utilized to evaluate the effect of Pgp-potentiated lysosomal targeting of drugs to overcome MDR. To assess the mechanism of how Dp44mT overcomes drug resistance, cellular studies utilized Pgp inhibitors, Pgp silencing, lysosomotropic agents, proliferation assays, immunoblotting, a Pgp-ATPase activity assay, radiolabeled drug uptake/efflux, a rhodamine 123 retention assay, lysosomal membrane permeability assessment, and DCF (2',7'-dichlorofluorescin) redox studies. Anti-tumor activity and selectivity of Dp44mT in Pgp-expressing, MDR cells versus drug-sensitive cells were studied using a BALB/c nu/nu xenograft mouse model. We demonstrate that Dp44mT is transported by the lysosomal Pgp drug pump, causing lysosomal targeting of Dp44mT and resulting in enhanced cytotoxicity in MDR cells. Lysosomal Pgp and pH were shown to be crucial for increasing Dp44mT-mediated lysosomal damage and subsequent cytotoxicity in drug-resistant cells, with Dp44mT being demonstrated to be a Pgp substrate. Indeed, Pgp-dependent lysosomal damage and cytotoxicity of Dp44mT were abrogated by Pgp inhibitors, Pgp silencing, or increasing lysosomal pH using lysosomotropic bases. In vivo, Dp44mT potently targeted chemotherapy-resistant human Pgp-expressing xenografted tumors relative to non-Pgp-expressing tumors in mice. This study highlights a novel Pgp hijacking strategy of the unique dipyridylthiosemicarbazone series of thiosemicarbazones that overcome MDR via utilization of lysosomal Pgp transport activity.

  6. The Implementation of E1 Clock Recovery

    Directory of Open Access Journals (Sweden)

    Wang Ziyu

    2016-01-01

    Full Text Available Clock transform and recovery is of significant importance in microwave TDM service, and it is always extracted from the E1 line data stream in most cases. However, intrinsically uncertain delay and jitter caused by packet transmission of E1 data information, may lead to the indexes of the data recovery clock exceed the clock performance template. Through analysis of the E1 clock indexes and measuring methods, this paper proposes a new clock recovery method. The method employs two buffers, the first RAM is used as a buffer to deduct excess information, and the second FIFO is used as a buffer to recovery the clock and data. The first buffer has a feedback from the second one, and is able to actively respond to changes in the data link and requests from the second one. The test results validate the effectiveness of the method, and the corresponding scheme is also valuable for the other communication systems.

  7. Recent Progress in Electrochemical Biosensors for Glycoproteins.

    Science.gov (United States)

    Akiba, Uichi; Anzai, Jun-Ichi

    2016-12-01

    This review provides an overview of recent progress in the development of electrochemical biosensors for glycoproteins. Electrochemical glycoprotein sensors are constructed by combining metal and carbon electrodes with glycoprotein-selective binding elements including antibodies, lectin, phenylboronic acid and molecularly imprinted polymers. A recent trend in the preparation of glycoprotein sensors is the successful use of nanomaterials such as graphene, carbon nanotube, and metal nanoparticles. These nanomaterials are extremely useful for improving the sensitivity of glycoprotein sensors. This review focuses mainly on the protocols for the preparation of glycoprotein sensors and the materials used. Recent improvements in glycoprotein sensors are discussed by grouping the sensors into several categories based on the materials used as recognition elements.

  8. Recent Progress in Electrochemical Biosensors for Glycoproteins

    Directory of Open Access Journals (Sweden)

    Uichi Akiba

    2016-12-01

    Full Text Available This review provides an overview of recent progress in the development of electrochemical biosensors for glycoproteins. Electrochemical glycoprotein sensors are constructed by combining metal and carbon electrodes with glycoprotein-selective binding elements including antibodies, lectin, phenylboronic acid and molecularly imprinted polymers. A recent trend in the preparation of glycoprotein sensors is the successful use of nanomaterials such as graphene, carbon nanotube, and metal nanoparticles. These nanomaterials are extremely useful for improving the sensitivity of glycoprotein sensors. This review focuses mainly on the protocols for the preparation of glycoprotein sensors and the materials used. Recent improvements in glycoprotein sensors are discussed by grouping the sensors into several categories based on the materials used as recognition elements.

  9. Age-related changes of the multidrug resistance P-glycoprotein function in normal human peripheral blood T lymphocytes

    Directory of Open Access Journals (Sweden)

    C.G. Machado

    2003-12-01

    Full Text Available The multidrug resistance P-glycoprotein is a transmembrane efflux pump expressed by lymphocytes and is involved in their cytolytic activity. In the present study, we investigated the age-related changes of P-glycoprotein function in normal peripheral blood lymphocytes. Blood samples from 90 normal volunteers (age range, 0 to 86 years were analyzed. P-glycoprotein function was assessed by the flow cytometric rhodamine 123 assay. P-glycoprotein function was highest in cord blood and progressively declined with age in peripheral blood T CD4+ and CD8+ cells. In contrast, P-glycoprotein function did not vary with age in CD19+ B or CD16+CD56+ natural killer cells. These data suggest that the decline in P-glycoprotein function in T CD4+ and CD8+ lymphocytes as a function of age may contribute to the decrease in T cell cytolytic activity with aging.

  10. Secretion of hepatitis C virus envelope glycoproteins depends on assembly of apolipoprotein B positive lipoproteins.

    Directory of Open Access Journals (Sweden)

    Vinca Icard

    Full Text Available The density of circulating hepatitis C virus (HCV particles in the blood of chronically infected patients is very heterogeneous. The very low density of some particles has been attributed to an association of the virus with apolipoprotein B (apoB positive and triglyceride rich lipoproteins (TRL likely resulting in hybrid lipoproteins known as lipo-viro-particles (LVP containing the viral envelope glycoproteins E1 and E2, capsid and viral RNA. The specific infectivity of these particles has been shown to be higher than the infectivity of particles of higher density. The nature of the association of HCV particles with lipoproteins remains elusive and the role of apolipoproteins in the synthesis and assembly of the viral particles is unknown. The human intestinal Caco-2 cell line differentiates in vitro into polarized and apoB secreting cells during asymmetric culture on porous filters. By using this cell culture system, cells stably expressing E1 and E2 secreted the glycoproteins into the basal culture medium after one week of differentiation concomitantly with TRL secretion. Secreted glycoproteins were only detected in apoB containing density fractions. The E1-E2 and apoB containing particles were unique complexes bearing the envelope glycoproteins at their surface since apoB could be co-immunoprecipitated with E2-specific antibodies. Envelope protein secretion was reduced by inhibiting the lipidation of apoB with an inhibitor of the microsomal triglyceride transfer protein. HCV glycoproteins were similarly secreted in association with TRL from the human liver cell line HepG2 but not by Huh-7 and Huh-7.5 hepatoma cells that proved deficient for lipoprotein assembly. These data indicate that HCV envelope glycoproteins have the intrinsic capacity to utilize apoB synthesis and lipoprotein assembly machinery even in the absence of the other HCV proteins. A model for LVP assembly is proposed.

  11. [Induction of rat hepatic CYP2E1 expression by arecoline in vivo].

    Science.gov (United States)

    Huang, Xiang-tao; Xiao, Run-mei; Wang, Ming-feng; Wang, Jun-jun; Chen, Yong

    2016-01-01

    The regulation mechanism of arecoline on rat hepatic CYP2E1 was studied in vivo. After oral administration of arecoline hydrobromide (AH; 4, 20 and 100 mg x kg(-1) x d(-1)) to rats for one week, the hepatic CYP2E1 mRNA level remained unchanged, but the hepatic CYP2E1 protein content was dose-dependently increased. Additionally, although the hepatic CYP2E1 activity was induced by AH treatment, the induction was attenuated with the increase in dosage. The results indicate that the effect of arecoline on rat hepaticdoes not involve transcriptional activation of the gene, but largely involves the stabilization of CYP2E1 protein against degradation or increased efficiency of CYP2E1 mRNA translation, and additionally involve the post- ranslational modification of CYP2E1 protein. Furthermore, the CYP2E1 response is fairly equal among the different species, the induction of rat hepatic CYP2E1 by arecoline suggests that there is a risk of metabolic interaction among the substrate drugs of CYP2E1 in betel-quid use human.

  12. E1 strength in N = 82 nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, T.; Volz, S.; Babilon, M.; Mohr, P.; Vogt, K.; Zilges, A

    2003-05-19

    Recently the importance of small contributions of electric dipole strength near the particle threshold to the production rates of atomic nuclei has become evident. Prior estimates concentrated on the Giant Dipole Resonance (GDR) which dominates photoabsorption in all nuclei. Extrapolations to smaller excitation energies were assumed to be sufficiently reliable. However, new measurements reveal that collective E1 strength can be found in the threshold region.

  13. E1M1 and E1E2 transition probabilities in one-electron ions

    Science.gov (United States)

    Labzowsky, L. N.; Shonin, A. V.

    2004-12-01

    The quantum electrodynamical (QED) theory of the two-photon transitions in hydrogenlike ions is presented. The emission probability for 2s→2γ(E1)+1s transitions is calculated and compared to the results of the previous calculations. The emission probabilities 2p→γ(E1)+γ(E2)+1s and 2p→γ(E1)+γ(M1)+1s are also calculated for the nuclear charge Z values 1⩽Z⩽100. This is the first calculation of the two latter probabilities. The results are given in two different gauges.

  14. Reelin glycoprotein: structure, biology and roles in health and disease.

    Science.gov (United States)

    Fatemi, S H

    2005-03-01

    Reelin glycoprotein is a secretory serine protease with dual roles in mammalian brain: embryologically, it guides neurons and radial glial cells to their corrected positions in the developing brain; in adult brain, Reelin is involved in a signaling pathway which underlies neurotransmission, memory formation and synaptic plasticity. Disruption of Reelin signaling pathway by mutations and selective hypermethylation of the Reln gene promoter or following various pre- or postnatal insults may lead to cognitive deficits present in neuropsychiatric disorders like autism or schizophrenia.

  15. Glycoproteins of the carcinoembryonic antigen (CEA) family are expressed in sweat and sebaceous glands of human fetal and adult skin.

    Science.gov (United States)

    Metze, D; Bhardwaj, R; Amann, U; Eades-Perner, A M; Neumaier, M; Wagener, C; Jantscheff, P; Grunert, F; Luger, T A

    1996-01-01

    The carcinoembryonic antigen (CEA) family comprises a group of glycoproteins including the classical CEA, nonspecific cross-reacting antigens (NCA), and biliary glycoprotein (BGP). CEA glycoproteins have been identified in many glandular and mucosal tissues. In view of their putative role in cell adhesion, protein sorting, and signal transduction, CEA glycoproteins are thought to be involved in embryogenesis, architectual integrity, and secretory mechanisms of glandular epithelia. Since there are few data available on the expression of CEA-like proteins in human skin, the aim of this study was to immunohistochemically specify and localize the CEA glycoproteins in cutaneous adult and fetal glands using a panel of well-characterized antibodies. The secretory parts of eccrine sweat glands expressed CEA, NCA-90, and BGP, whereas apocrine glands remained unreactive for CEA glycoproteins. The ductal epithelia of both eccrine and apocrine glands contained CEA and NCA-90. Sebaceous glands were stained for BGP only. Electron microscopy of sweat glands showed CEA glycoprotein expression in cytoplasmic organelles and on microvilli lining the ductal surface. In sebaceous glands, BGP were demonstrated in small vesicles and along the cell membranes of differentiating sebocytes. Fetal development of cutaneous glands was associated with early expression of CEA glycoproteins. Additionally, mice transgenic for human CEA were shown to express CEA in sweat glands. The overall distribution of CEA glycoproteins in cutaneous glands was consistent with that in epithelia of other glandular tissues.

  16. Immunological aspects of pregnancy-associated glycoproteins.

    Science.gov (United States)

    Dosogne, H; Massart-Leën, A M; Burvenich, C

    2000-01-01

    The incidence of severe cases of acute E. coli mastitis in dairy cows is highest during early lactation. This phenomenon has been associated with a decreased function and decreased numbers of circulating polymorphonuclear neutrophil leukocytes (PMN). The cause of this impaired function and decreased number is poorly understood. Stress, hormonal and metabolic alterations around parturition and the onset of lactation may play a role in this phenomenon. Several molecules, such as cortisol and beta-hydroxybutyrate have been found to alter the oxidative burst activity of circulating PMN around parturition. Pregnancy-Associated Glycoprotein (bPAG) could also be involved. The theory of immunosuppression by bPAG was investigated because analogous glycoproteins produced by the placenta of other species exert local immunosuppression in order to maintain the histoincompatible feto-maternal unit. The production and subsequent release into the maternal circulation of bPAG is ensured by the binucleate cells from the trophoblast and starts already at implantation. However, peak levels are only reached 1 week before parturition. Due to the long half-life time of this molecule, high levels are found in plasma until 2 weeks after calving. The co-occurrence of the impairment of PMN oxidative burst activity in the early postpartum period and a peak in plasma bPAG concentrations might support the hypothesis of an immunosuppressive effect of PAG. Moreover, an inhibitory effect of bPAG on the proliferation of bovine bone marrow progenitor cells has been found recently in our laboratory. bPAG occurs in colostrum, but its effect on milk cells has not been clarified. It is concluded that interaction between the physiology of reproduction and lactation on the one side and immune function on the other side in dairy cattle requires further research.

  17. The role of cyclin E1 in hepatocellular carcinoma

    OpenAIRE

    Chan, Yan-yan; 陳茵茵

    2014-01-01

    Hepatocellular carcinoma (HCC) accounts for 70-85% of liver cancer, which is the sixth most common cancer in the world. Prognosis of HCC is dismal with little chance of complete recovery after diagnosis. It is of essence to discover the key molecules involved in the tumor progression. This could help earlier detection of HCC and establish targeted molecular therapies. Cyclin E1 (CCNE1) is a cyclin molecule responsible for the transition from G1 to S phase of the cell cycle and is often dysreg...

  18. Blood-brain barrier P-glycoprotein function in healthy subjects and Alzheimer's disease patients : Effect of polymorphisms in the ABCB1 gene

    NARCIS (Netherlands)

    D.M.E. van Assema (Daniëlle); M. Lubberink (Mark); P. Rizzu (Patrizia); J.C. van Swieten (John); R.C. Schuit (Robert); J. Eriksson (Joel); P. Scheltens (Philip); M. Koepp (Matthias); A.A. Lammertsma (Adriaan); B.N.M. van Berckel (Bart )

    2012-01-01

    textabstractBackground: P-glycoprotein is a blood-brain barrier efflux transporter involved in the clearance of amyloid-beta from the brain and, as such, might be involved in the pathogenesis of Alzheimer's disease. P-glycoprotein is encoded by the highly polymorphic ABCB1 gene. Single-nucleotide po

  19. N-glycoprotein analysis discovers new up-regulated glycoproteins in colorectal cancer tissue.

    Science.gov (United States)

    Nicastri, Annalisa; Gaspari, Marco; Sacco, Rosario; Elia, Laura; Gabriele, Caterina; Romano, Roberto; Rizzuto, Antonia; Cuda, Giovanni

    2014-11-07

    Colorectal cancer is one of the leading causes of death due to cancer worldwide. Therefore, the identification of high-specificity and -sensitivity biomarkers for the early detection of colorectal cancer is urgently needed. Post-translational modifications, such as glycosylation, are known to play an important role in cancer progression. In the present work, we used a quantitative proteomic technique based on (18)O stable isotope labeling to identify differentially expressed N-linked glycoproteins in colorectal cancer tissue samples compared with healthy colorectal tissue from 19 patients undergoing colorectal cancer surgery. We identified 54 up-regulated glycoproteins in colorectal cancer samples, therefore potentially involved in the biological processes of tumorigenesis. In particular, nine of these (PLOD2, DPEP1, SE1L1, CD82, PAR1, PLOD3, S12A2, LAMP3, OLFM4) were found to be up-regulated in the great majority of the cohort, and, interestingly, the association with colorectal cancer of four (PLOD2, S12A2, PLOD3, CD82) has not been hitherto described.

  20. E1M1 and E1E2 transition probabilities in one-electron ions

    Energy Technology Data Exchange (ETDEWEB)

    Labzowsky, L.N. [Institute of Physics, St. Petersburg State University, Uljanovskaya 1, Petrodvorets, 198904 St. Petersburg (Russian Federation) and Petersburg Nuclear Physics Institute, Gatchina, 188350 St. Petersburg (Russian Federation)]. E-mail: leonti@landau.phys.spbu.ru; Shonin, A.V. [Institute of Physics, St. Petersburg State University, Uljanovskaya 1, Petrodvorets, 198904 St. Petersburg (Russian Federation)

    2004-12-06

    The quantum electrodynamical (QED) theory of the two-photon transitions in hydrogenlike ions is presented. The emission probability for 2s1/2->2{gamma}(E1)+1s1/2 transitions is calculated and compared to the results of the previous calculations. The emission probabilities 2p1/2->{gamma}(E1)+{gamma}(E2)+1s1/2 and 2p1/2->{gamma}(E1)+{gamma}(M1)+1s1/2 are also calculated for the nuclear charge Z values 1=

  1. Brain Barriers and a Subpopulation of Astroglial Progenitors of Developing Human Forebrain Are Immunostained for the Glycoprotein YKL-40

    DEFF Research Database (Denmark)

    Bjørnbak, Camilla; Brøchner, Christian B; Larsen, Lars A

    2014-01-01

    YKL-40, a glycoprotein involved in cell differentiation, has been associated with neurodevelopmental disorders, angiogenesis, neuroinflammation and glioblastomas. We evaluated YKL-40 protein distribution in the early human forebrain using double-labeling immunofluorescence and immunohistochemistry...

  2. Adenovirus E1A/E1B Transformed Amniotic Fluid Cells Support Human Cytomegalovirus Replication

    Directory of Open Access Journals (Sweden)

    Natascha Krömmelbein

    2016-02-01

    Full Text Available The human cytomegalovirus (HCMV replicates to high titers in primary human fibroblast cell cultures. A variety of primary human cells and some tumor-derived cell lines do also support permissive HCMV replication, yet at low levels. Cell lines established by transfection of the transforming functions of adenoviruses have been notoriously resistant to HCMV replication and progeny production. Here, we provide first-time evidence that a permanent cell line immortalized by adenovirus type 5 E1A and E1B (CAP is supporting the full HCMV replication cycle and is releasing infectious progeny. The CAP cell line had previously been established from amniotic fluid cells which were likely derived from membranes of the developing fetus. These cells can be grown under serum-free conditions. HCMV efficiently penetrated CAP cells, expressed its immediate-early proteins and dispersed restrictive PML-bodies. Viral DNA replication was initiated and viral progeny became detectable by electron microscopy in CAP cells. Furthermore, infectious virus was released from CAP cells, yet to lower levels compared to fibroblasts. Subviral dense bodies were also secreted from CAP cells. The results show that E1A/E1B expression in transformed cells is not generally repressive to HCMV replication and that CAP cells may be a good substrate for dense body based vaccine production.

  3. Salmonid alphavirus glycoprotein E2 requires low temperature and E1 for virion formation and induction of protective immunity

    NARCIS (Netherlands)

    Hikke, M.C.; Braaen, S.; Villoing, S.; Hodneland, K.; Geertsema, C.; Verhagen, L.; Frost, P.; Vlak, J.M.; Rimstad, E.; Pijlman, G.P.

    2014-01-01

    Salmonid alphavirus (SAV; also known as Salmon pancreas disease virus; family Togaviridae) causes pancreas disease and sleeping disease in Atlantic salmon and rainbow trout, respectively, and poses a major burden to the aquaculture industry. SAV infection in vivo is temperature-restricted and

  4. Salmonid alphavirus glycoprotein E2 requires low temperature and E1 for virion formation and induction of protective immunity

    NARCIS (Netherlands)

    Hikke, M.C.; Braaen, S.; Villoing, S.; Hodneland, K.; Geertsema, C.; Verhagen, L.; Frost, P.; Vlak, J.M.; Rimstad, E.; Pijlman, G.P.

    2014-01-01

    Salmonid alphavirus (SAV; also known as Salmon pancreas disease virus; family Togaviridae) causes pancreas disease and sleeping disease in Atlantic salmon and rainbow trout, respectively, and poses a major burden to the aquaculture industry. SAV infection in vivo is temperature-restricted and progen

  5. Human CYP2E1 mediates the formation of glycidamide from acrylamide.

    Science.gov (United States)

    Settels, Eva; Bernauer, Ulrike; Palavinskas, Richard; Klaffke, Horst S; Gundert-Remy, Ursula; Appel, Klaus E

    2008-10-01

    Regarding the cancer risk assessment of acrylamide (AA) it is of basic interest to know, as to what amount of the absorbed AA is metabolized to glycidamide (GA) in humans, compared to what has been observed in laboratory animals. GA is suspected of being the ultimate carcinogenic metabolite of AA. From experiments with CYP2E1-deficient mice it can be concluded that AA is metabolized to GA primarily by CYP2E1. We therefore examined whether CYP2E1 is involved in GA formation in non-rodent species with the focus on humans by using human CYP2E1 supersomes, marmoset and human liver microsomes and in addition, genetically engineered V79 cells expressing human CYP2E1 (V79h2E1 cells). Special emphasis was placed on the analytical detection of GA, which was performed by gas chromatography/mass spectrometry. The results show that AA is metabolized to GA in human CYP2E1 supersomes, in marmoset and human liver microsomes as well as in V79h2E1 cells. The activity of GA formation is highest in supersomes; in human liver it is somewhat higher than in marmoset liver. A monoclonal CYP2E1 human selective antibody (MAB-2E1) and diethyldithiocarbamate (DDC) were used as specific inhibitors of CYP2E1. The generation of GA could be inhibited by MAB-2E1 to about 80% in V79h2E1 cells and to about 90% in human and marmoset liver microsomes. Also DDC led to an inhibition of about 95%. In conclusion, AA is metabolized to GA by human CYP2E1. Overall, the present work describes (1) the application and refinement of a sensitive methodology in order to determine low amounts of GA, (2) the applicability of genetically modified V79 cell lines in order to investigate specific questions concerning metabolism and (3) the involvement, for the first time, of human CYP2E1 in the formation of GA from AA. Further studies will compare the activities of GA formation in genetically engineered V79 cells expressing CYP2E1 from different species.

  6. Human CYP2E1 mediates the formation of glycidamide from acrylamide

    Energy Technology Data Exchange (ETDEWEB)

    Settels, Eva; Appel, Klaus E. [Federal Institute for Risk Assessment, Center for Experimental Toxicology, Berlin (Germany); Bernauer, Ulrike; Gundert-Remy, Ursula [Federal Institute for Risk Assessment, Department of Safety of Substances and Preparations, Berlin (Germany); Palavinskas, Richard; Klaffke, Horst S. [Federal Institute for Risk Assessment, Center for Analytical Chemistry, Berlin (Germany)

    2008-10-15

    Regarding the cancer risk assessment of acrylamide (AA) it is of basic interest to know, as to what amount of the absorbed AA is metabolized to glycidamide (GA) in humans, compared to what has been observed in laboratory animals. GA is suspected of being the ultimate carcinogenic metabolite of AA. From experiments with CYP2E1-deficient mice it can be concluded that AA is metabolized to GA primarily by CYP2E1. We therefore examined whether CYP2E1 is involved in GA formation in non-rodent species with the focus on humans by using human CYP2E1 supersomes trademark, marmoset and human liver microsomes and in addition, genetically engineered V79 cells expressing human CYP2E1 (V79h2E1 cells). Special emphasis was placed on the analytical detection of GA, which was performed by gas chromatography/mass spectrometry. The results show that AA is metabolized to GA in human CYP2E1 supersomes trademark, in marmoset and human liver microsomes as well as in V79h2E1 cells. The activity of GA formation is highest in supersomes trademark; in human liver it is somewhat higher than in marmoset liver. A monoclonal CYP2E1 human selective antibody (MAB-2E1) and diethyldithiocarbamate (DDC) were used as specific inhibitors of CYP2E1. The generation of GA could be inhibited by MAB-2E1 to about 80% in V79h2E1 cells and to about 90% in human and marmoset liver microsomes. Also DDC led to an inhibition of about 95%. In conclusion, AA is metabolized to GA by human CYP2E1. Overall, the present work describes (1) the application and refinement of a sensitive methodology in order to determine low amounts of GA, (2) the applicability of genetically modified V79 cell lines in order to investigate specific questions concerning metabolism and (3) the involvement, for the first time, of human CYP2E1 in the formation of GA from AA. Further studies will compare the activities of GA formation in genetically engineered V79 cells expressing CYP2E1 from different species. (orig.)

  7. Methodology to assay CYP2E1 mixed function oxidase catalytic activity and its induction

    Directory of Open Access Journals (Sweden)

    Arthur I. Cederbaum

    2014-01-01

    Full Text Available The cytochrome P450 mixed function oxidase enzymes are the major catalysts involved in drug metabolism. There are many forms of P450. CYP2E1 metabolizes many toxicologically important compounds including ethanol and is active in generating reactive oxygen species. Since several of the contributions in the common theme series “Role of CYP2E1 and Oxidative/Nitrosative Stress in the Hepatotoxic Actions of Alcohol” discuss CYP2E1, this methodology review describes assays on how CYP2E1 catalytic activity and its induction by ethanol and other inducers can be measured using substrate probes such as the oxidation of para-nitrophenol to para-nitrocatechol and the oxidation of ethanol to acetaldehyde. Approaches to validate that a particular reaction e.g. oxidation of a drug or toxin is catalyzed by CYP2E1 or that induction of that reaction is due to induction of CYP2E1 are important and specific examples using inhibitors of CYP2E1, anti-CYP2E1 IgG or CYP2E1 knockout and knockin mice will be discussed.

  8. CYP2E1 mediated isoniazid-induced hepatotoxicity in rats

    Institute of Scientific and Technical Information of China (English)

    Jiang YUE; Ren-xiu PENG; Jing YANG; Rui KONG; Juan LIU

    2004-01-01

    AIM: To investigate the role of CYP2E1 in isoniazid (INH)-induced hepatotoxicity and the influence of rifampicin (RFP) on INH-induced liver injury. METHODS: Rats were treated with INH alone (100 mg/kg, ip) or co-administered with RFP (100 mg/kg, ig) for 10 d and 21 d. Hepatotoxicity was assayed by plasma enzymes (sALT, sAST) and histopathological examinations. Hepatic CYP2E1 activity was measured by aniline hydroxylase (ANH), and CYP2E1 mRNA expression was determined by RT-PCR. Plasma hydrazine concentration was determined by RP-HPLC.RESULTS: For a 10 d INH-treatment, hepatic CYP2E1 level was increased to 3.7-fold over the control; liver impairment appeared after 21 d treatment, while CYP2E1 and plasma hydrazine were, respectively, increased to 4.6-fold and 1.7-fold. However, in INH-RFP group for 10 d, CYP2E1 and plasma hydrazine were, respectively,decreased by 13 % and 18 % over INH group; similarly, hepatic injury is equal to INH group appeared after 21 d,and CYP2E1 was further decreased by 26 %. Correlation analysis showed that sALT had a positive correlation with plasma hydrazine and with CYP2E1 activity; CYP2E1 activity was also markedly correlated with plasma hydrazine.And compared with control, there is no difference in changes of CYP2E1 mRNA expression in INH and INH-RFP treatment for 21 d. CONCLUSION: The metabolite of INH, hydrazine, plays an important role in INH-induced hepatotoxicity in rats. The induction of CYP2E1 by hydrazine is involved in the hepatotoxicity of INH. RFP does not exacerbate INH-induced hepatotoxicity in short term, which relates to down-regulation of CYP2E1.

  9. Pathogenesis of mucosal injury in the blind loop syndrome. Brush border enzyme activity and glycoprotein degradation.

    Science.gov (United States)

    Jonas, A; Flanagan, P R; Forstner, G G

    1977-12-01

    The effect of intestinal bacterial over-growth on brush border hydrolases and brush border glycoproteins was studied in nonoperated control rats, control rats with surgically introduced jejunal self-emptying blind loops, and rats with surgically introduced jejunal self-filling blind loops. Data were analyzed from blind loop segments, segments above and below the blind loops, and three corresponding segments in the nonoperated controls. Rats with self-filling blind loops had significantly greater fat excretion than controls and exhibited significantly lower conjugated:free bile salt ratios in all three segments. Maltase, sucrase, and lactase activities were significantly reduced in homogenates and isolated brush borders from the self-filling blind loop, but alkaline phosphatase was not affected. The relative degradation rate of homogenate and brush border glycoproteins was assessed by a double-isotope technique involving the injection of d-[6-(3)H]glucosamine 3 h and d-[U-(14)C]glucosamine 19 h before sacrifice, and recorded as a (3)H:(14)C ratio. The relative degradation rate in both homogenate and brush border fractions was significantly greater in most segments from rats with self-filling blind loops. In the upper and blind loop segments from rats with self-filling blind loops, the (3)H:(14)C ratios were higher in the brush border membrane than in the corresponding homogenates, indicating that the increased rates of degradation primarily involve membrane glycoproteins. Incorporation of d-[6-(3)H]glucosamine by brush border glycoproteins was not reduced in rats with self-filling blind loops, suggesting that glycoprotein synthesis was not affected. Polyacrylamide gel electrophoresis of brush border glycoproteins from the contaminated segments indicated that the large molecular weight glycoproteins, which include many of the surface hydrolases, were degraded most rapidly. Brush border maltase, isolated by immunoprecipitation, had (3)H:(14)C ratios characteristic of

  10. Bypassing P-Glycoprotein Drug Efflux Mechanisms: Possible Applications in Pharmacoresistant Schizophrenia Therapy

    Directory of Open Access Journals (Sweden)

    Famida G. Hoosain

    2015-01-01

    Full Text Available The efficient noninvasive treatment of neurodegenerative disorders is often constrained by reduced permeation of therapeutic agents into the central nervous system (CNS. A vast majority of bioactive agents do not readily permeate into the brain tissue due to the existence of the blood-brain barrier (BBB and the associated P-glycoprotein efflux transporter. The overexpression of the MDR1 P-glycoprotein has been related to the occurrence of multidrug resistance in CNS diseases. Various research outputs have focused on overcoming the P-glycoprotein drug efflux transporter, which mainly involve its inhibition or bypassing mechanisms. Studies into neurodegenerative disorders have shown that the P-glycoprotein efflux transporter plays a vital role in the progression of schizophrenia, with a noted increase in P-glycoprotein function among schizophrenic patients, thereby reducing therapeutic outcomes. In this review, we address the hypothesis that methods employed in overcoming P-glycoprotein in cancer and other disease states at the level of the BBB and intestine may be applied to schizophrenia drug delivery system design to improve clinical efficiency of drug therapies. In addition, the current review explores polymers and drug delivery systems capable of P-gp inhibition and modulation.

  11. Role of sialidase in glycoprotein utilization by Tannerella forsythia.

    Science.gov (United States)

    Roy, Sumita; Honma, Kiyonobu; Douglas, C W Ian; Sharma, Ashu; Stafford, Graham P

    2011-11-01

    The major bacterial pathogens associated with periodontitis include Tannerella forsythia. We previously discovered that sialic acid stimulates biofilm growth of T. forsythia, and that sialidase activity is key to utilization of sialoconjugate sugars and is involved in host-pathogen interactions in vitro. The aim of this work was to assess the influence of the NanH sialidase on initial biofilm adhesion and growth in experiments where the only source of sialic acid was sialoglycoproteins or human oral secretions. After showing that T. forsythia can utilize sialoglycoproteins for biofilm growth, we showed that growth and initial adhesion with sialylated mucin and fetuin were inhibited two- to threefold by the sialidase inhibitor oseltamivir. A similar reduction (three- to fourfold) was observed with a nanH mutant compared with the wild-type. Importantly, these data were replicated using clinically relevant serum and saliva samples as substrates. In addition, the ability of the nanH mutant to form biofilms on glycoprotein-coated surfaces could be restored by the addition of purified NanH, which we show is able to cleave sialic acid from the model glycoprotein fetuin and, much less efficiently, 9-O-acetylated bovine submaxillary mucin. These data show for the first time that glycoprotein-associated sialic acid is likely to be a key in vivo nutrient source for T. forsythia when growing in a biofilm, and suggest that sialidase inhibitors might be useful adjuncts in periodontal therapy.

  12. Acrosome reaction: relevance of zona pellucida glycoproteins

    Institute of Scientific and Technical Information of China (English)

    Satish K Gupta; Beena Bhandari

    2011-01-01

    During mammalian fertilisation,the zona pellucida(ZP)matrix surrounding the oocyte is responsible for the binding of the spermatozoa to the oocyte and induction of the acrosome reaction(AR)in the ZP-bound spermatozoon.The AR is crucial for the penetration of the ZP matrix by spermatozoa.The ZP matrix in mice is composed of three glycoproteins designated ZP1,ZP2 and ZP3,whereas in humans,it is composed of four(ZP1,ZP2,ZP3 and ZP4).ZP3 acts as the putative primary sperm receptor and is responsible for AR induction in mice,whereas in humans(in addition to ZP3),ZP1 and ZP4 also induce the AR.The ability of ZP3 to induce the AR resides in its C-terminal fragment.O-linked glycans are critical for the murine ZP3-mediated AR.However,N-linked glycans of human ZP1,ZP3 and ZP4 have important roles in the induction of the AR.Studies with pharmacological inhibitors showed that the ZP3-induced AR involves the activation of the G1-coupled receptor pathway,whereas ZP1-and ZP4-mediated ARs are independent of this pathway.The ZP3-induced AR involves the activation of T-type voltage-operated calcium channels(VOCCs),whereas ZP1-and ZP4-induced ARs involve both T-and L-type VOCCs.To conclude,in mice,ZP3 is primarily responsible for the binding of capacitated spermatozoa to the ZP matrix and induction of the AR,whereas in humans(in addition to ZP3),ZP1 and ZP4 also participate in these stages of fertilisation.

  13. Hepatitis C Virus E2 Envelope Glycoprotein Core Structure

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Leopold; Giang, Erick; Nieusma, Travis; Kadam, Rameshwar U.; Cogburn, Kristin E.; Hua, Yuanzi; Dai, Xiaoping; Stanfield, Robyn L.; Burton, Dennis R.; Ward, Andrew B.; Wilson, Ian A.; Law, Mansun

    2014-08-26

    Hepatitis C virus (HCV), a Hepacivirus, is a major cause of viral hepatitis, liver cirrhosis, and hepatocellular carcinoma. HCV envelope glycoproteins E1 and E2 mediate fusion and entry into host cells and are the primary targets of the humoral immune response. The crystal structure of the E2 core bound to broadly neutralizing antibody AR3C at 2.65 angstroms reveals a compact architecture composed of a central immunoglobulin-fold β sandwich flanked by two additional protein layers. The CD81 receptor binding site was identified by electron microscopy and site-directed mutagenesis and overlaps with the AR3C epitope. The x-ray and electron microscopy E2 structures differ markedly from predictions of an extended, three-domain, class II fusion protein fold and therefore provide valuable information for HCV drug and vaccine design.

  14. Reduction of benzene metabolism and toxicity in mice that lack CYP2E1 expression.

    Science.gov (United States)

    Valentine, J L; Lee, S S; Seaton, M J; Asgharian, B; Farris, G; Corton, J C; Gonzalez, F J; Medinsky, M A

    1996-11-01

    Transgenic CYP2E1 knockout mice (cyp2e1-/-) were used to investigate the involvement of CYP2E1 in the in vivo metabolism of benzene and in the development of benzene-induced toxicity. After benzene exposure, absence of CYP2E1 protein was confirmed by Western blot analysis of mouse liver samples. For the metabolism studies, male cyp2e1-/- and wild-type control mice were exposed to 200 ppm benzene, along with a radiolabeled tracer dose of [14C]benzene (1.0 Ci/mol) by nose-only inhalation for 6 hr. Total urinary radioactivity and all radiolabeled individual metabolites were reduced in urine of cyp2e1-/- mice compared to wild-type controls during the 48-hr period after benzene exposure. In addition, a significantly greater percentage of total urinary radioactivity could be accounted for as phenylsulfate conjugates in cyp2e1-/- mice compared to wild-type mice, indicating the importance of CYP2E1 in oxidation of phenol following benzene exposure in normal mice. For the toxicity studies, male cyp2e1-/-, wild-type, and B6C3F1 mice were exposed by whole-body inhalation to 0 ppm (control) or 200 ppm benzene, 6 hr/day for 5 days. On Day 5, blood, bone marrow, thymus, and spleen were removed for evaluation of micronuclei frequencies and tissue cellularities. No benzene-induced cytotoxicity or genotoxicity was observed in cyp2e1-/- mice. In contrast, benzene exposure resulted in severe genotoxicity and cytotoxicity in both wild-type and B6C3F1 mice. These studies conclusively demonstrate that CYP2E1 is the major determinant of in vivo benzene metabolism and benzene-induced myelotoxicity in mice.

  15. Increased Expression of P-Glycoprotein Is Associated With Chlorpyrifos Resistance in the German Cockroach (Blattodea: Blattellidae).

    Science.gov (United States)

    Hou, Weiyuan; Jiang, Chu; Zhou, Xiaojie; Qian, Kun; Wang, Lei; Shen, Yanhui; Zhao, Yan

    2016-09-15

    A principal method for control of the German cockroach, Blattella germanica (L.), is the broad-spectrum organophosphorus insecticide, chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate); however, extensive and repeated application has resulted in the development of resistance to chlorpyrifos in this insect. Evidence suggests that ATP-binding cassette protein transporters, including P-glycoprotein, are involved in insecticide resistance. However, little is known of the role of P-glycoprotein in insecticide resistance in the German cockroach. Here, we developed a chlorpyrifos-resistant strain of German cockroach and investigated the relationship between P-glycoprotein and chlorpyrifos resistance using toxicity assays; inhibition studies with two P-glycoprotein inhibitors, verapamil and quinine; P-glycoprotein-ATPase activity assays; and western blotting analysis. After 23 generations of selection from susceptible strain cockroaches, we obtained animals with high resistance to chlorpyrifos. When P-glycoprotein-ATPase activity was inhibited by verapamil and quinine, we observed enhanced susceptibility to chlorpyrifos in both control and chlorpyrifos-resistant cockroaches. No significant alterations of P-glycoprotein expression or ATPase activity were observed in cockroaches acutely exposed to LD50 doses of chlorpyrifos for 24 h, while P-glycoprotein expression and ATPase activity were clearly elevated in the chlorpyrifos-resistant cockroach strain. Thus, we conclude that P-glycoprotein is associated with chlorpyrifos resistance in the German cockroach and that elevated levels of P-glycoprotein expression and ATPase activity may be an important mechanism of chlorpyrifos resistance in the German cockroach.

  16. Main: 1E1E [RPSD[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1E トウモロコシ Corn Zea mays L. Beta-Glucosidase, Chloroplast Precursor Name=Glu1; Zea...TDDAYASQEVNGPDGKPIGPPMGNPWIYMYPEGLKDLLMIMKNKYGNPPIYITENGIGDVDTKETPLPMEAALNDYKRLDYIQRHIATLKESIDLGSNVQGYFAWSLLDNFEWFAGFTERYGIVYVDRNNNCTRYMKESAKWLKEFNTAKKPSKKILTPA corn_1E1E.jpg ...

  17. Main: 1E1F [RPSD[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1F トウモロコシ Corn Zea mays L. Beta-Glucosidase, Chloroplast Precursor Name=Glu1; Zea...QRHIATLKESIDLGSNVQGYFAWSLLDNFEWFAGFTERYGIVYVDRNNNCTRYMKESAKWLKEFNTAKKPSKKILTPA corn_1E1F.jpg ...

  18. Ovine Herpesvirus 2 Glycoproteins B, H, and L Are Sufficient for, and Viral Glycoprotein Ov8 Can Enhance, Cell-Cell Membrane Fusion.

    Science.gov (United States)

    AlHajri, Salim M; Cunha, Cristina W; Nicola, Anthony V; Aguilar, Hector C; Li, Hong; Taus, Naomi S

    2017-03-15

    Ovine herpesvirus 2 (OvHV-2) is a gammaherpesvirus in the genus Macavirus that is carried asymptomatically by sheep. Infection of poorly adapted animals with OvHV-2 results in sheep-associated malignant catarrhal fever, a fatal disease characterized by lymphoproliferation and vasculitis. There is no treatment or vaccine for the disease and no cell culture system to propagate the virus. The lack of cell culture has hindered studies of OvHV-2 biology, including its entry mechanism. As an alternative method to study OvHV-2 glycoproteins responsible for membrane fusion as a part of the entry mechanism, we developed a virus-free cell-to-cell membrane fusion assay to identify the minimum required OvHV-2 glycoproteins to induce membrane fusion. OvHV-2 glycoproteins B, H, and L (gB, gH, and gL) were able to induce membrane fusion together but not when expressed individually. Additionally, open reading frame Ov8, unique to OvHV-2, was found to encode a transmembrane glycoprotein that can significantly enhance membrane fusion. Thus, OvHV-2 gB, gH, and gL are sufficient to induce membrane fusion, while glycoprotein Ov8 plays an enhancing role by an unknown mechanism.IMPORTANCE Herpesviruses enter cells via attachment of the virion to the cellular surface and fusion of the viral envelope with cellular membranes. Virus-cell membrane fusion is an important step for a successful viral infection. Elucidating the roles of viral glycoproteins responsible for membrane fusion is critical toward understanding viral entry. Entry of ovine herpesvirus 2 (OvHV-2), the causative agent of sheep associated-malignant catarrhal fever, which is one of the leading causes of death in bison and other ungulates, has not been well studied due to the lack of a cell culture system to propagate the virus. The identification of OvHV-2 glycoproteins that mediate membrane fusion may help identify viral and/or cellular factors involved in OvHV-2 cell tropism and will advance investigation of cellular

  19. In vitro generation of human cytotoxic lymphocytes by virus. Viral glycoproteins induce nonspecific cell-mediated cytotoxicity without release of interferon.

    Science.gov (United States)

    Casali, P; Sissons, J G; Buchmeier, M J; Oldstone, M B

    1981-09-01

    Purified hemagglutinin and fusion glycoproteins of measles virus either in soluble form or inserted in artifical membranes bind to human peripheral blood lymphocytes and induce cell-mediated cytotoxicity (CMC) in a dose-response fashion. Both autologous and heterologous noninfected target cells are lysed in vitro. The expression of CMC is not inhibited by anti-measles virus antibody added to lymphocytes previously exposed to viral glycoproteins. THe killer lymphocytes are Fc receptor positive, both erythrocyte-rosetting and non-erythrocyte-rosetting, as assessed by both positive and negative selection experiments. The induction of nonspecific CMC by viral glycoproteins either in the soluble state or inserted into artificial membranes could be segregated from the CMC associated with whole virions. First, on kinetics studies, purified viral glycoproteins induced CMC more rapidly than did whole virus. Second, viral glycoprotein-produced response occurred in the absence of detectable release of interferon into the culture medium, whereas CMC activity due to whole virions was associated with interferon release. The fact that purified measles virus glycoproteins integrated into artificial membrane bilayers were as efficient as their soluble counterparts in inducing CMC suggests that the hydrophobic portion of the glycoproteins was not involved in the induction and expression of the lytic activity. Purified glycoproteins from lymphocytic choriomeningitis virus behave similarly, although this virus is unrelated to measles virus. It is inferred that interferon-independent CMC induced by viral glycoproteins might account for some of the biological reactions occurring early in the control of a viral infection.

  20. CYP2E1-dependent elevation of serum cholesterol, triglycerides, and hepatic bile acids by isoniazid.

    Science.gov (United States)

    Cheng, Jie; Krausz, Kristopher W; Li, Feng; Ma, Xiaochao; Gonzalez, Frank J

    2013-01-15

    Isoniazid is the first-line medication in the prevention and treatment of tuberculosis. Isoniazid is known to have a biphasic effect on the inhibition-induction of CYP2E1 and is also considered to be involved in isoniazid-induced hepatotoxicity. However, the full extent and mechanism of involvement of CYP2E1 in isoniazid-induced hepatotoxicity remain to be thoroughly investigated. In the current study, isoniazid was administered to wild-type and Cyp2e1-null mice to investigate the potential toxicity of isoniazid in vivo. The results revealed that isoniazid caused no hepatotoxicity in wild-type and Cyp2e1-null mice, but produced elevated serum cholesterol and triglycerides, and hepatic bile acids in wild-type mice, as well as decreased abundance of free fatty acids in wild-type mice and not in Cyp2e1-null mice. Metabolomic analysis demonstrated that production of isoniazid metabolites was elevated in wild-type mice along with a higher abundance of bile acids, bile acid metabolites, carnitine and carnitine derivatives; these were not observed in Cyp2e1-null mice. In addition, the enzymes responsible for bile acid synthesis were decreased and proteins involved in bile acid transport were significantly increased in wild-type mice. Lastly, treatment of targeted isoniazid metabolites to wild-type mice led to similar changes in cholesterol, triglycerides and free fatty acids. These findings suggest that while CYP2E1 is not involved in isoniazid-induced hepatotoxicity, while an isoniazid metabolite might play a role in isoniazid-induced cholestasis through enhancement of bile acid accumulation and mitochondria β-oxidation. Published by Elsevier Inc.

  1. E1DS: catalytic site prediction based on 1D signatures of concurrent conservation.

    Science.gov (United States)

    Chien, Ting-Ying; Chang, Darby Tien-Hao; Chen, Chien-Yu; Weng, Yi-Zhong; Hsu, Chen-Ming

    2008-07-01

    Large-scale automatic annotation of protein sequences remains challenging in postgenomics era. E1DS is designed for annotating enzyme sequences based on a repository of 1D signatures. The employed sequence signatures are derived using a novel pattern mining approach that discovers long motifs consisted of several sequential blocks (conserved segments). Each of the sequential blocks is considerably conserved among the protein members of an EC group. Moreover, a signature includes at least three sequential blocks that are concurrently conserved, i.e. frequently observed together in sequences. In other words, a sequence signature is consisted of residues from multiple regions of the protein sequence, which echoes the observation that an enzyme catalytic site is usually constituted of residues that are largely separated in the sequence. E1DS currently contains 5421 sequence signatures that in total cover 932 4-digital EC numbers. E1DS is evaluated based on a collection of enzymes with catalytic sites annotated in Catalytic Site Atlas. When compared to the famous pattern database PROSITE, predictions based on E1DS signatures are considered more sensitive in identifying catalytic sites and the involved residues. E1DS is available at http://e1ds.ee.ncku.edu.tw/ and a mirror site can be found at http://e1ds.csbb.ntu.edu.tw/.

  2. Structure of Pyrazole Derivatives Impact their Affinity, Stoichiometry, and Cooperative Interactions for CYP2E1 Complexes

    OpenAIRE

    2013-01-01

    CYP2E1 plays a critical role in detoxication and carcinogenic activation of drugs, pollutants, and dietary compounds; however, these metabolic processes can involve poorly characterized cooperative interactions that compromise the ability to understand and predict CYP2E1 metabolism. Herein, we employed an array of ten azoles with an emphasis on pyrazoles to establish the selectivity of catalytic and cooperative CYP2E1 sites through binding and catalytic studies. Spectral binding studies for m...

  3. Structure of Pyrazole Derivatives Impact their Affinity, Stoichiometry, and Cooperative Interactions for CYP2E1 Complexes

    OpenAIRE

    Hartman, Jessica H.; Bradley, Amber M.; Laddusaw, Ryan M.; Perry, Martin D.; Miller, Grover P.

    2013-01-01

    CYP2E1 plays a critical role in detoxication and carcinogenic activation of drugs, pollutants, and dietary compounds; however, these metabolic processes can involve poorly characterized cooperative interactions that compromise the ability to understand and predict CYP2E1 metabolism. Herein, we employed an array of ten azoles with an emphasis on pyrazoles to establish the selectivity of catalytic and cooperative CYP2E1 sites through binding and catalytic studies. Spectral binding studies for m...

  4. Haemonchus contortus P-glycoprotein-2: in situ localisation and characterisation of macrocyclic lactone transport.

    Science.gov (United States)

    Godoy, Pablo; Lian, Jing; Beech, Robin N; Prichard, Roger K

    2015-01-01

    Haemonchus contortus is a veterinary nematode that infects small ruminants, causing serious decreases in animal production worldwide. Effective control through anthelmintic treatment has been compromised by the development of resistance to these drugs, including the macrocyclic lactones. The mechanisms of resistance in H. contortus have yet to be established but may involve efflux of the macrocyclic lactones by nematode ATP-binding-cassette transporters such as P-glycoproteins. Here we report the expression and functional activity of H. contortus P-glycoprotein 2 expressed in mammalian cells and characterise its interaction with the macrocyclic lactones, ivermectin, abamectin and moxidectin. The ability of H. contortus P-glycoprotein 2 to transport different fluorophore substrates was markedly inhibited by ivermectin and abamectin in a dose-dependent and saturable way. The profile of transport inhibition by moxidectin was markedly different. H. contortus P-glycoprotein 2 was expressed in the pharynx, the first portion of the worm's intestine and perhaps in adjacent nervous tissue, suggesting a role for this gene in regulating the uptake of avermectins and in protecting nematode tissues from the effects of macrocyclic lactone anthelmintic drugs. H. contortus P-glycoprotein 2 may thus contribute to resistance to these drugs in H. contortus.

  5. Ammonia secretion from fish gill depends on a set of Rh glycoproteins.

    Science.gov (United States)

    Nakada, Tsutomu; Westhoff, Connie M; Kato, Akira; Hirose, Shigehisa

    2007-04-01

    Ammonia excretion from the gill in teleost fish is essential for nitrogen elimination. Although numerous physiological studies have measured ammonia excretion, the mechanism of ammonia movement through the membranes of gill epithelial cells is still unknown. Mammalian Rh glycoproteins are members of a family of proteins that mediate ammonia transport in bacteria, yeast, and plants. We identified the Rh glycoprotein homologs, fRhag, fRhbg, fRhcg1, and fRhcg2, of the pufferfish, Takifugu rubripes. Northern blot, in situ hybridization, and immunohistochemistry revealed that the pufferfish erythroid Rh glycoprotein homologue fRhag was present in red blood cells and the hematological organs (spleen and kidney) in fish. All four pufferfish Rh glycoproteins are specifically localized in the gill and line the pillar cells, pavement cells, and the mitochondrion-rich cells. Heterologous expression in Xenopus oocytes showed that they mediate methylammonium (an analog of ammonium) transport. These results suggest that pufferfish Rh glycoproteins are involved in ammonia excretion from the gill. These findings challenge the classic view that ammonia excretion in the fish gill occurs by passive diffusion.

  6. Defence sugarcane glycoproteins disorganize microtubules and prevent nuclear polarization and germination of Sporisorium scitamineum teliospores.

    Science.gov (United States)

    Sánchez-Elordi, Elena; Baluška, František; Echevarría, Clara; Vicente, Carlos; Legaz, M Estrella

    2016-08-01

    Microtubules (MTs) are involved in the germination of Sporisorium scitamineum teliospores. Resistant varieties of sugar cane plants produce defence glycoproteins that prevent the infection of the plants by the filamentous fungi Sporisorium scitamineum. Here, we show that a fraction of these glycoproteins prevents the correct arrangement of MTs and causes nuclear fragmentation defects. As a result, nuclei cannot correctly migrate through the growing hyphae, causing germinative failure. Arginase activity contained in defence glycoproteins is already described for preventing fungal germination. Now, its enzymatically active form is presented as a link between the defensive capacity of glycoproteins and the MT disorganization in fungal cells. Active arginase is produced in healthy and resistant plants; conversely, it is not detected in the juice from susceptible varieties, which explains why MT depolarization, nuclear disorganization as well as germination of teliospores are not significantly affected by glycoproteins from non-resistant plants. Our results also suggest that susceptible plants try to increase their levels of arginase after detecting the presence of the pathogen. However, this signal comes "too late" and such defensive mechanism fails.

  7. Dissemination and transmission of the E1-226V variant of chikungunya virus in Aedes albopictus are controlled at the midgut barrier level.

    Directory of Open Access Journals (Sweden)

    Camilo Arias-Goeta

    Full Text Available Emergence of arboviruses could result from their ability to exploit new environments, for example a new host. This ability is facilitated by the high mutation rate occurring during viral genome replication. The last emergence of chikungunya in the Indian Ocean region corroborates this statement since a single viral mutation at the position 226 on the E1 glycoprotein (E1-A226V was associated with enhanced transmission by the mosquito Aedes albopictus in regions where the major mosquito vector, Aedes aegypti, is absent.We used direct competition assays in vivo to dissect out the mechanisms underlying the selection of E1-226V by Ae. albopictus. When the original variant E1-226A and the newly emerged E1-226V were provided in the same blood-meal at equal titers to both species of mosquitoes, we found that the proportion of both variants was drastically different in the two mosquito species. Following ingestion of the infectious blood-meal, the E1-226V variant was preferentially selected in Ae. albopictus, whereas the E1-226A variant was sometimes favored in Ae. aegypti. Interestingly, when the two variants were introduced into the mosquitoes by intrathoracic inoculations, E1-226V was no longer favored for dissemination and transmission in Ae. albopictus, showing that the midgut barrier plays a key role in E1-226V selection.This study sheds light on the role of the midgut barrier in the selection of novel arbovirus emerging variants. We also bring new insight into how the pre-existing variant E1-226V was selected among other viral variants including E1-226A. Indeed the E1-226V variant present at low levels in natural viral populations could rapidly emerge after being selected in Ae. albopictus at the midgut barrier level.

  8. Platelet receptor expression and shedding: glycoprotein Ib-IX-V and glycoprotein VI.

    Science.gov (United States)

    Gardiner, Elizabeth E; Andrews, Robert K

    2014-04-01

    Quantity, quality, and lifespan are 3 important factors in the physiology, pathology, and transfusion of human blood platelets. The aim of this review is to discuss the proteolytic regulation of key platelet-specific receptors, glycoprotein(GP)Ib and GPVI, involved in the function of platelets in hemostasis and thrombosis, and nonimmune or immune thrombocytopenia. The scope of the review encompasses the basic science of platelet receptor shedding, practical aspects related to laboratory analysis of platelet receptor expression/shedding, and clinical implications of using the proteolytic fragments as platelet-specific biomarkers in vivo in terms of platelet function and clearance. These topics can be relevant to platelet transfusion regarding both changes in platelet receptor expression occurring ex vivo during platelet storage and/or clinical use of platelets for transfusion. In this regard, quantitative analysis of platelet receptor profiles on blood samples from individuals could ultimately enable stratification of bleeding risk, discrimination between causes of thrombocytopenia due to impaired production vs enhanced clearance, and monitoring of response to treatment prior to change in platelet count.

  9. New insights into FoxE1 functions: identification of direct FoxE1 targets in thyroid cells.

    Directory of Open Access Journals (Sweden)

    Lara P Fernández

    Full Text Available BACKGROUND: FoxE1 is a thyroid-specific forkhead transcription factor essential for thyroid gland development, as well as for the maintenance of the thyroid differentiated state in adults. FoxE1 recognizes and binds to a short DNA sequence present in thyroglobulin (Tg and thyroperoxidase (Tpo promoters, but FoxE1 binding to regulatory regions other than Tg and Tpo promoters remains almost unexplored. Improving knowledge of the regulatory functions of FoxE1 is necessary to clarify its role in endocrine syndromes and cancer susceptibility. METHODOLOGY/PRINCIPAL FINDING: In order to further investigate downstream FoxE1 targets, we performed a genome-wide expression screening after knocking-down FoxE1 and obtained new insights into FoxE1 transcriptional networks in thyroid follicular cells. After validation, we confirmed Adamts9, Cdh1, Duox2 and S100a4 as upregulated genes and Casp4, Creld2, Dusp5, Etv5, Hsp5a, Nr4a2 and Tm4sf1 as downregulated genes when FoxE1 was silenced. In promoter regions of putative FoxE1-regulated genes and also in the promoters of the classical thyroid genes Nis, Pax8 and Titf1, we performed an in silico search of the FoxE1 binding motif that was in close proximity to the NF1/CTF binding sequence, as previously described for other forkhead factors. Using chromatin immunoprecipitation we detected specific in vivo FoxE1 binding to novel regulatory regions in two relevant thyroid genes, Nis and Duox2. Moreover, we demonstrated simultaneous binding of FoxE1 and NF1/CTF to the Nis upstream enhancer region, as well as a clear functional activation of the Nis promoter by both transcription factors. CONCLUSIONS/SIGNIFICANCE: In search for potential downstream mediators of FoxE1 function in thyroid cells, we identified two novel direct FoxE1 target genes. To our knowledge, this is the first evidence regarding the implication of Nis and Duox2 in executing the transcriptional program triggered by FoxE1. Furthermore, this study points

  10. 26 CFR 1.927(e)-1 - Special sourcing rule.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 10 2010-04-01 2010-04-01 false Special sourcing rule. 1.927(e)-1 Section 1.927... (CONTINUED) INCOME TAXES Earned Income of Citizens of United States § 1.927(e)-1 Special sourcing rule. (a... under section 925 with respect to such transaction applied to such transaction. This special sourcing...

  11. 26 CFR 1.514(e)-1 - Allocation rules.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 7 2010-04-01 2010-04-01 true Allocation rules. 1.514(e)-1 Section 1.514(e)-1... Allocation rules. Where only a portion of property is debt-financed property, proper allocation of the basis...)(iii) of § 1.514(b)-1 for illustrations of proper allocation....

  12. 26 CFR 1.642(e)-1 - Depreciation and depletion.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Depreciation and depletion. 1.642(e)-1 Section 1... (CONTINUED) INCOME TAXES Estates, Trusts, and Beneficiaries § 1.642(e)-1 Depreciation and depletion. An estate or trust is allowed the deductions for depreciation and depletion, but only to the extent...

  13. Isolation of glycoproteins from brown algae

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme...

  14. Activation of the human beta interferon gene by the adenovirus type 12 E1B gene

    Energy Technology Data Exchange (ETDEWEB)

    Shiroki, K.; Toth, M.

    1988-01-01

    The transcription of endogenous beta interferon mRNA was activated in human embryo kidney (HEK) cells infected with adenovirus 12 (Ad12) but was activated only inefficiently or not at all in HEK cells infected with Ad5 and rc-1 (Ad5 dl312 containing the Ad12 E1A region). The analysis with Ad12 mutants showed that Ad12 E1B products, especially the 19K protein, were important for the expression of the endogenous beta interferon gene and Ad12 E1A products were not involved in the expression. The expression of exogeneously transfected pIFN-CAT (a hybrid plasmid having the human beta interferon promoter fused with the CAT gene) was activated in HEK and chicken embryo fibroblast (CEF) cells infected with either Ad12 or Ad5. The analysis of cotransfection of CEF cells with pIFN-CAT and plasmids containing fragments of Ad12 or Ad5 DNA showed that Ad12 or Ad5 E1B (possibly the 19K protein) was and E1A was not involved in the expression of the exogenous pIFN-CAT.

  15. Identification of a mouse synaptic glycoprotein gene in cultured neurons.

    Science.gov (United States)

    Yu, Albert Cheung-Hoi; Sun, Chun Xiao; Li, Qiang; Liu, Hua Dong; Wang, Chen Ran; Zhao, Guo Ping; Jin, Meilei; Lau, Lok Ting; Fung, Yin-Wan Wendy; Liu, Shuang

    2005-10-01

    Neuronal differentiation and aging are known to involve many genes, which may also be differentially expressed during these developmental processes. From primary cultured cerebral cortical neurons, we have previously identified various differentially expressed gene transcripts from cultured cortical neurons using the technique of arbitrarily primed PCR (RAP-PCR). Among these transcripts, clone 0-2 was found to have high homology to rat and human synaptic glycoprotein. By in silico analysis using an EST database and the FACTURA software, the full-length sequence of 0-2 was assembled and the clone was named as mouse synaptic glycoprotein homolog 2 (mSC2). DNA sequencing revealed transcript size of mSC2 being smaller than the human and rat homologs. RT-PCR indicated that mSC2 was expressed differentially at various culture days. The mSC2 gene was located in various tissues with higher expression in brain, lung, and liver. Functions of mSC2 in neurons and other tissues remain elusive and will require more investigation.

  16. Heterologous expression of human cytochrome P450 2E1 in HepG2 cell line

    Institute of Scientific and Technical Information of China (English)

    Jian Zhuge; Ye Luo; Ying-Nian Yu

    2003-01-01

    AIM: Human cytochrome P-450 2E1 (CYP2E1) takes part in the biotransformation of ethanol, acetone, many smallmolecule substrates and volatile anesthetics. CYP2E1 is involved in chemical activation of many carcinogens,procarcinogens, and toxicants. To assess the metabolic and toxicological characteristics of CYP2E1, we cloned CYP2E1 cDNA and established a HepG2 cell line stably expressing recombinant CYP 2E1.METHODS: Human CYP2E1 cDNA was amplified with reverse transcription-polymerase chain reaction (RT-PCR)from total RNAs extracted from human liver and cloned into pGEM-T vector. The cDNA segment was identified by DNA sequencing and subcloned into a mammalian expression vector pREP9. A transgenic cell line was established by transfecting the recombinant plasmid of pREP9-CYP2E1 to HepG2 cells. The expression of CYP2E1 mRNA was validated by RT-PCR. The enzyme activity of CYP2E1 catalyzing oxidation of 4-nitrophenol in postmitochondrial supernate (S9) fraction of the cells was determined by spectrophotometry. The metabolic activation of HepG2-CYP2E1 cells was assayed by N-nitrosodiethylamine (NDEA)cytotoxicity and micronucleus test.RESULTS: The cloned CYP2E1 cDNA segment was identical to that reported by Umeno et al(GenBank access No.J02843). HepG2-CYP2E1 cells expressed CYP2E1 mRNA and had 4-nitrophenol hydroxylase activity (0.162±0.025nmol.min-1.mg-1 S9 protein), which were undetectable in parent HepG2 cells. HepG2-CYP2E1 cells increased the cytotoxicity and micronucleus rate of NDEA in comparison with those of HepG2 cells.CONCLUSION: The cDNA of human CYP2E1 can be successfully cloned, and a cell line, HepG2-CYP2E1, which can efficiently express mRNA and has CYP2E1 activity, is established. The cell line is useful for testing the cytotoxicity,mutagenicity and metabolism of xenobiotics, which may possibly be activated or metabolized by CYP2E1.

  17. Structure of a trimeric variant of the Epstein-Barr virus glycoprotein B

    Energy Technology Data Exchange (ETDEWEB)

    Backovic, Marija [Northwestern Univ., Evanston, IL (United States); Longnecker, Richard [Northwestern Univ., Chicago, IL (United States); Jardetzky, Theodore S [Northwestern Univ., Evanston, IL (United States)

    2009-03-16

    Epstein-Barr virus (EBV) is a herpesvirus that is associated with development of malignancies of lymphoid tissue. EBV infections are life-long and occur in >90% of the population. Herpesviruses enter host cells in a process that involves fusion of viral and cellular membranes. The fusion apparatus is comprised of envelope glycoprotein B (gB) and a heterodimeric complex made of glycoproteins H and L. Glycoprotein B is the most conserved envelope glycoprotein in human herpesviruses, and the structure of gB from Herpes simplex virus 1 (HSV-1) is available. Here, we report the crystal structure of the secreted EBV gB ectodomain, which forms 16-nm long spike-like trimers, structurally homologous to the postfusion trimers of the fusion protein G of vesicular stomatitis virus (VSV). Comparative structural analyses of EBV gB and VSV G, which has been solved in its pre and postfusion states, shed light on gB residues that may be involved in conformational changes and membrane fusion. Also, the EBV gB structure reveals that, despite the high sequence conservation of gB in herpesviruses, the relative orientations of individual domains, the surface charge distributions, and the structural details of EBV gB differ from the HSV-1 protein, indicating regions and residues that may have important roles in virus-specific entry.

  18. Structure of a trimeric variant of the Epstein-Barr virus glycoprotein B.

    Science.gov (United States)

    Backovic, Marija; Longnecker, Richard; Jardetzky, Theodore S

    2009-02-24

    Epstein-Barr virus (EBV) is a herpesvirus that is associated with development of malignancies of lymphoid tissue. EBV infections are life-long and occur in >90% of the population. Herpesviruses enter host cells in a process that involves fusion of viral and cellular membranes. The fusion apparatus is comprised of envelope glycoprotein B (gB) and a heterodimeric complex made of glycoproteins H and L. Glycoprotein B is the most conserved envelope glycoprotein in human herpesviruses, and the structure of gB from Herpes simplex virus 1 (HSV-1) is available. Here, we report the crystal structure of the secreted EBV gB ectodomain, which forms 16-nm long spike-like trimers, structurally homologous to the postfusion trimers of the fusion protein G of vesicular stomatitis virus (VSV). Comparative structural analyses of EBV gB and VSV G, which has been solved in its pre and postfusion states, shed light on gB residues that may be involved in conformational changes and membrane fusion. Also, the EBV gB structure reveals that, despite the high sequence conservation of gB in herpesviruses, the relative orientations of individual domains, the surface charge distributions, and the structural details of EBV gB differ from the HSV-1 protein, indicating regions and residues that may have important roles in virus-specific entry.

  19. CYP2E1-dependent elevation of serum cholesterol, triglycerides, and hepatic bile acids by isoniazid

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Jie; Krausz, Kristopher W. [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Li, Feng; Ma, Xiaochao [Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, 4089 KLSIC, MS 1018, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States); Gonzalez, Frank J., E-mail: fjgonz@helix.nih.gov [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

    2013-01-15

    Isoniazid is the first-line medication in the prevention and treatment of tuberculosis. Isoniazid is known to have a biphasic effect on the inhibition–induction of CYP2E1 and is also considered to be involved in isoniazid-induced hepatotoxicity. However, the full extent and mechanism of involvement of CYP2E1 in isoniazid-induced hepatotoxicity remain to be thoroughly investigated. In the current study, isoniazid was administered to wild-type and Cyp2e1-null mice to investigate the potential toxicity of isoniazid in vivo. The results revealed that isoniazid caused no hepatotoxicity in wild-type and Cyp2e1-null mice, but produced elevated serum cholesterol and triglycerides, and hepatic bile acids in wild-type mice, as well as decreased abundance of free fatty acids in wild-type mice and not in Cyp2e1-null mice. Metabolomic analysis demonstrated that production of isoniazid metabolites was elevated in wild-type mice along with a higher abundance of bile acids, bile acid metabolites, carnitine and carnitine derivatives; these were not observed in Cyp2e1-null mice. In addition, the enzymes responsible for bile acid synthesis were decreased and proteins involved in bile acid transport were significantly increased in wild-type mice. Lastly, treatment of targeted isoniazid metabolites to wild-type mice led to similar changes in cholesterol, triglycerides and free fatty acids. These findings suggest that while CYP2E1 is not involved in isoniazid-induced hepatotoxicity, while an isoniazid metabolite might play a role in isoniazid-induced cholestasis through enhancement of bile acid accumulation and mitochondria β-oxidation. -- Highlights: ► Isoniazid metabolites were elevated only in wild-type mice. ► Isoniazid caused no hepatotoxicity in wild-type and Cyp2e1-null mice. ► Isoniazid elevated serum cholesterol and triglycerides, and hepatic bile acids. ► Bile acid transporters were significantly decreased in isoniazid-treated mice.

  20. P-glycoprotein alters blood–brain barrier penetration of antiepileptic drugs in rats with medically intractable epilepsy

    Directory of Open Access Journals (Sweden)

    Ma A

    2013-12-01

    Full Text Available Aimei Ma,1,* Cuicui Wang,2,3,* Yinghui Chen,2,3 Weien Yuan4 1Department of Neurology, The People's Hospital of Shanxi Province, Taiyuan, 2Department of Neurology, Jinshan Hospital, Fudan University, 3Department of Neurology, Shanghai Medical College, Shanghai, 4School of Pharmacy, Shanghai JiaoTong University, Shanghai, People's Republic of China *These authors contributed equally to this work Abstract: P-glycoprotein is one of the earliest known multidrug transporters and plays an important role in resistance to chemotherapeutic drugs. In this study, we detected levels of P-glycoprotein and its mRNA expression in a rat brain model of medically intractable epilepsy established by amygdala kindling and drug selection. We investigated whether inhibition of P-glycoprotein affects the concentration of antiepileptic drugs in cortical extracellular fluid. We found that levels of P-glycoprotein and its mRNA expression were upregulated in epileptic cerebral tissue compared with cerebral tissue from normal rats. The concentrations of two antiepileptic drugs, carbamazepine and phenytoin, were very low in the cortical extracellular fluid of rats with medically intractable epilepsy, and were restored after blockade of P-glycoprotein by verapamil. These results show that increased P-glycoprotein levels alter the ability of carbamazepine and phenytoin to penetrate the blood–brain barrier and reduce the concentrations of these agents in extracellular cortical fluid. High P-glycoprotein levels may be involved in resistance to antiepileptic drugs in medically intractable epilepsy. Keywords: P-glycoprotein, medically intractable epilepsy, antiepileptic drugs, amygdala kindling, verapamil

  1. A distance regular graph of type E1 Ed

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this note, the distance regular graph of type E1 Ed is considered and some characterization of the type graph is given. The results generalize the characterization of tight distance regular graphs.

  2. Mutation in E1, the ubiquitin activating enzyme, reduces Drosophila lifespan and results in motor impairment.

    Science.gov (United States)

    Liu, Hsiu-Yu; Pfleger, Cathie M

    2013-01-01

    Neurodegenerative diseases cause tremendous suffering for those afflicted and their families. Many of these diseases involve accumulation of mis-folded or aggregated proteins thought to play a causal role in disease pathology. Ubiquitinated proteins are often found in these protein aggregates, and the aggregates themselves have been shown to inhibit the activity of the proteasome. These and other alterations in the Ubiquitin Pathway observed in neurodegenerative diseases have led to the question of whether impairment of the Ubiquitin Pathway on its own can increase mortality or if ongoing neurodegeneration alters Ubiquitin Pathway function as a side-effect. To address the role of the Ubiquitin Pathway in vivo, we studied loss-of-function mutations in the Drosophila Ubiquitin Activating Enzyme, Uba1 or E1, the most upstream enzyme in the Ubiquitin Pathway. Loss of only one functional copy of E1 caused a significant reduction in adult lifespan. Rare homozygous hypomorphic E1 mutants reached adulthood. These mutants exhibited further reduced lifespan and showed inappropriate Ras activation in the brain. Removing just one functional copy of Ras restored the lifespan of heterozygous E1 mutants to that of wild-type flies and increased the survival of homozygous E1 mutants. E1 homozygous mutants also showed severe motor impairment. Our findings suggest that processes that impair the Ubiquitin Pathway are sufficient to cause early mortality. Reduced lifespan and motor impairment are seen in the human disease X-linked Infantile Spinal Muscular Atrophy, which is associated with mutation in human E1 warranting further analysis of these mutants as a potential animal model for study of this disease.

  3. Platelet Glycoprotein lb-1X and Malignancy

    Science.gov (United States)

    2011-09-01

    patient with systemic lupus erythematosus . Am J Hematol 2001; 67:262-67. 20. Arthur JF, Dunkley S and Andrews RK. Platelet glycoprotein VI-related...Moroi M. Antibody against platelet membrane glyco- protein VI in a patient with systemic lupus erythematosus . Am J Hematol 2001; 67: 262–7. 9 Arthur JF...Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the

  4. Stereoselective Modulation of P-Glycoprotein by Chiral Small Molecules.

    Science.gov (United States)

    Carocci, Alessia; Catalano, Alessia; Turi, Francesco; Lovece, Angelo; Cavalluzzi, Maria M; Bruno, Claudio; Colabufo, Nicola A; Contino, Marialessandra; Perrone, Maria G; Franchini, Carlo; Lentini, Giovanni

    2016-01-01

    Inhibition of drug efflux pumps such as P-glycoprotein (P-gp) is an approach toward combating multidrug resistance, which is a significant hurdle in current cancer treatments. To address this, N-substituted aryloxymethyl pyrrolidines were designed and synthesized in their homochiral forms in order to investigate the stereochemical requirements for the binding site of P-gp. Our study provides evidence that the chiral property of molecules could be a strategy for improving the capacity for interacting with P-gp, as the most active compounds of the series stereoselectively modulated this efflux pump. The naphthalene-1-yl analogue (R)-2-[(2,3-dichlorophenoxy)methyl]-1-(naphthalen-1-ylmethyl)pyrrolidine) [(R)-7 a] emerged foremost for its potency and stereoselectivity toward P-gp, with the S enantiomer being nearly inactive. The modulation of P-gp by (R)-7 a involved consumption of ATP, thus demonstrating that the compound behaves as a P-gp substrate.

  5. Silencing E1A mRNA by RNA interference inhibits adenovirus replication.

    Science.gov (United States)

    Chung, Y-S; Kim, M-K; Lee, W-J; Kang, C

    2007-01-01

    The adenovirus family contains 51 human serotypes, and most human adenoviruses cause widespread respiratory tract infections. Adenovirus infections can result in severe complications in some cases, such as in adenovirus type 11 infection in immunocompromised patients. However, effective treatment methods for adenovirus infections are currently unavailable. This prompted the search for antiviral agents effective against adenovirus infections. In the present study, adenovirus E1A was targeted by RNA interference (RNAi) using synthetic small interfering RNAs (siRNAs) in an attempt to inhibit viral replication, since adenovirus E1A proteins are known to be involved in the transcriptional activation of the viral and cellular genes necessary for controlling the cell cycle and viral replication. The results indicated that the siRNAs effectively reduced the amount of adenovirus E1A mRNA and the levels of replicative intermediates. Additionally, siRNA-mediated gene silencing inhibited adenovirus replication by suppressing the E1A mRNA. These results suggest that the RNAi-mediated targeting of adenovirus E1A may have a potentially therapeutic effect in controlling adenovirus infections.

  6. Interaction of mouse hepatitis virus (MHV) spike glycoprotein with receptor glycoprotein MHVR is required for infection with an MHV strain that expresses the hemagglutinin-esterase glycoprotein

    NARCIS (Netherlands)

    Gagneten, S; Gout, O; Dubois-Dalcq, M; Rottier, P; Rossen, J; Holmes, K V

    1995-01-01

    In addition to the spike (S) glycoprotein that binds to carcinoembryonic antigen-related receptors on the host cell membrane, some strains of mouse coronavirus (mouse hepatitis virus [MHV]) express a hemagglutinin esterase (HE) glycoprotein with hemagglutinating and acetylesterase activity. Virions

  7. The isolation of the ectodomain of the alphavirus E1 protein as a soluble hemagglutinin and its crystallization.

    Science.gov (United States)

    Wengler, G; Wengler, G; Rey, F A

    1999-05-10

    Alphaviruses are isometric enveloped viruses approximately 70 nm in diameter. The viral surface contains 80 glycoprotein spikes arranged in a T = 4 lattice. Each of these spikes consists of three heterodimers of the viral membrane proteins E1 (approximately 49 kDa) and E2 (approximately 51 kDa). Cryoelectron microscopic analyses have shown that the spikes form a protein shell on the viral surface. We have made an attempt to isolate biologically active protein fragments from this surface and to grow crystals from such fragments. To this end membrane proteins were extracted with Nonidet-P40 from the Semliki Forest alphavirus and the proteins were separated from detergent by centrifugation. A protein complex containing the E1 and E2 molecules in quantitative yield was obtained by this procedure. This complex has the following properties: It sediments at approximately 30S, it chromatographs with an apparent molecular mass of approximately 580,000 Da during gel filtration, it cannot be dissociated by either nonionic detergents or 6 M urea, and at acid pH it is a highly active hemagglutinin. The data indicate that this 30S hemagglutinin complex, which has not been hitherto described for alphaviruses, may represent a variant form of the protein lattice present on the alphavirus surface. Cleavage of this complex by subtilisin selectively removes carboxy-terminal sequences from the E1 and E2 proteins, which contain the cytoplasmic and transmembrane segments of the proteins and a small part of their ectodomain. The remaining ectodomains are called E1DeltaS and E2DeltaS. This proteolysis also leads to dissociation of the 30S complex. The cleavage products accumulate in the form of a heterodimer of the E1DeltaS and E2DeltaS proteins. Treatment of the heterodimer with PNGase F leads to rapid removal of carbohydrate from the E2DeltaS protein and a dissociation of the complex into the constituent molecules, which can be separated by chromatography. The finding that the

  8. Oncolytic Replication of E1b-Deleted Adenoviruses

    Directory of Open Access Journals (Sweden)

    Pei-Hsin Cheng

    2015-11-01

    Full Text Available Various viruses have been studied and developed for oncolytic virotherapies. In virotherapy, a relatively small amount of viruses used in an intratumoral injection preferentially replicate in and lyse cancer cells, leading to the release of amplified viral particles that spread the infection to the surrounding tumor cells and reduce the tumor mass. Adenoviruses (Ads are most commonly used for oncolytic virotherapy due to their infection efficacy, high titer production, safety, easy genetic modification, and well-studied replication characteristics. Ads with deletion of E1b55K preferentially replicate in and destroy cancer cells and have been used in multiple clinical trials. H101, one of the E1b55K-deleted Ads, has been used for the treatment of late-stage cancers as the first approved virotherapy agent. However, the mechanism of selective replication of E1b-deleted Ads in cancer cells is still not well characterized. This review will focus on three potential molecular mechanisms of oncolytic replication of E1b55K-deleted Ads. These mechanisms are based upon the functions of the viral E1B55K protein that are associated with p53 inhibition, late viralmRNAexport, and cell cycle disruption.

  9. Primary scientific results of Chang’E-1 lunar mission

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The strategic plan for the development of the unmanned Chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first Chinese lunar probe, Chang’E-1, which was successfully launched on October 24th, 2007 at Xichang Satellite Launch Center, and guided to crash on the Moon on March 1st, 2009, at 52.36°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang’E-1 mission lasted 495 days, exceeding the expected life-span by about four months. A total of 1.37 TB raw data was received from Chang’E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first Chinese lunar explora- tion mission". All scientific goals of Chang’E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future Chinese lunar missions.

  10. Performance Analysis of Two Ethernet over E1 Schemes

    Institute of Scientific and Technical Information of China (English)

    CHEN Wentao; JIN Depeng; ZENG Lieguang

    2007-01-01

    The Ethernet over E1 approach,which takes advantage of widely deployed telecom networks,is an efficient and economical way to interconnect two Ethernets in different regions.Two Ethernet over E1 schemes, namely a byte granularity scheme and a frame granularity scheme are discussed. The byte granularity scheme partitions Ethernet frames into several pieces for transmission and has a strict requirement on the maximum delay difference of multiple E1 links. To solve this problem, the newly proposed frame granularity scheme transmits separately each frame through E1 links without any partitioning. The architecture designs of both schemes are presented. This paper evaluates the throughput and delay performances of both schemes, both analytically from results calculated from delay models and using test results from field programmable gate array (FPGA) implementation. Although the frame granularity scheme has a slightly worse delay performance, it has a higher throughput, and is the only choice able to overcome large delay differences of the E1 links.

  11. Profiling of Concanavalin A-Binding Glycoproteins in Human Hepatic Stellate Cells Activated with Transforming Growth Factor-β1

    Directory of Open Access Journals (Sweden)

    Yannan Qin

    2014-11-01

    Full Text Available Glycoproteins play important roles in maintaining normal cell functions depending on their glycosylations. Our previous study indicated that the abundance of glycoproteins recognized by concanavalin A (ConA was increased in human hepatic stellate cells (HSCs following activation by transforming growth factor-β1 (TGF-β1; however, little is known about the ConA-binding glycoproteins (CBGs of HSCs. In this study, we employed a targeted glycoproteomics approach using lectin-magnetic particle conjugate-based liquid chromatography-tandem mass spectrometry to compare CBG profiles between LX-2 HSCs with and without activation by TGF-β1, with the aim of discovering novel CBGs and determining their possible roles in activated HSCs. A total of 54 and 77 proteins were identified in the quiescent and activated LX-2 cells, respectively. Of the proteins identified, 14.3% were glycoproteins and 73.3% were novel potential glycoproteins. Molecules involved in protein processing in the endoplasmic reticulum (e.g., calreticulin and calcium signaling (e.g., 1-phosphatidylinositol-4,5-bisphosphate phosphodiesterase β-2 [PLCB2] were specifically identified in activated LX-2 cells. Additionally, PLCB2 expression was upregulated in the cytoplasm of the activated LX-2 cells, as well as in the hepatocytes and sinusoidal cells of liver cirrhosis tissues. In conclusion, the results of this study may aid future investigations to find new molecular mechanisms involved in HSC activation and antifibrotic therapeutic targets.

  12. Analgesic effects of glycoproteins from Panax ginseng root in mice.

    Science.gov (United States)

    Wang, Ying; Chen, Yinghong; Xu, Hong; Luo, Haoming; Jiang, Ruizhi

    2013-07-30

    The root of Panax ginseng C.A. Mey has various beneficial pharmacological effects. The present study aimed to evaluate the analgesic activities of glycoproteins from the root of Panax ginseng C.A. Mey in mice. Glycoproteins were isolated and purified from the root of Panax ginseng C.A. Mey. Physicochemical properties and molecular mass were determined by chemical assay and HPLC. Acetic acid-induced writhing and hot-plate tests were employed to study the analgesic effect of glycoproteins and compared with that of aspirin or morphine. The locomotor activity was tested in mice by using actophometer. Four glycoproteins were obtained. The glycoproteins which protein content was the highest (73.04%) displayed dose-dependent analgesic effect. In writhing test, the glycoproteins significantly inhibited writhes (PPanax ginseng C.A. Mey exhibited significant analgesic activities and the proteins were the active site, providing evidence for its pharmacal use. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Chang'e-1 Satellite Completed Its Preset Objectives

    Institute of Scientific and Technical Information of China (English)

    He Ying

    2008-01-01

    @@ By October 23, Chang'e-1 satellite with a one-year design lifetime has been operating in lunar orbit for one year, completed more than 4000 orbits, covering the entire moon 12 times. The satellite's platform works normally at present and all systems and equipment onboard work in their main mode. The satellite has obtained a large quantity of scientific data and achieved the preset objectives of precise orbit maneuver, successful moon orbiting, effective exploration and oneyear lifetime. The Chang'e-1 mission is a complete success.

  14. Human CRISP-3 binds serum alpha(1)B-glycoprotein across species

    DEFF Research Database (Denmark)

    Udby, Lene; Johnsen, Anders H; Borregaard, Niels

    2010-01-01

    CRISP-3 was previously shown to be bound to alpha(1)B-glycoprotein (A1BG) in human serum/plasma. All mammalian sera are supposed to contain A1BG, although its presence in rodent sera is not well-documented. Since animal sera are often used to supplement buffers in experiments, in particular such ...... such that involve cell cultures, binding proteins present in sera might interfere in the experiments....

  15. SPAK and OSR1 Sensitive Cell Membrane Protein Abundance and Activity of KCNQ1/E1 K+ Channels

    Directory of Open Access Journals (Sweden)

    Bernat Elvira

    2015-11-01

    Full Text Available Background/Aims: KCNQ1/E1 channels are expressed in diverse tissues and serve a variety of functions including endolymph secretion in the inner ear, cardiac repolarization, epithelial transport and cell volume regulation. Kinases involved in regulation of epithelial transport and cell volume include SPAK (SPS1-related proline/alanine-rich kinase and OSR1 (oxidative stress-responsive kinase 1, which are under control of WNK (with-no-K[Lys] kinases. The present study explored whether KCNQ1/E1 channels are regulated by SPAK and/or OSR1. Methods: cRNA encoding KCNQ1/E1 was injected into Xenopus oocytes with or without additional injection of cRNA encoding wild-type SPAK, constitutively active T233ESPAK, WNK insensitive T233ASPAK, catalytically inactive D212ASPAK, wild-type OSR1, constitutively active T185EOSR1, WNK insensitive T185AOSR1 and catalytically inactive D164AOSR1. Voltage gated K+ channel activity was quantified utilizing dual electrode voltage clamp and KCNQ1/E1 channel protein abundance in the cell membrane utilizing chemiluminescence of KCNQ1/E1 containing an extracellular Flag tag epitope (KCNQ1-Flag/E1. Results: KCNQ1/E1 activity and KCNQ1-Flag/E1 protein abundance were significantly enhanced by wild-type SPAK and T233ESPAK, but not by T233ASPAK and D212ASPAK. Similarly, KCNQ1/E1 activity and KCNQ1-Flag/E1 protein abundance were significantly increased by wild-type OSR1 and T185EOSR1, but not by T185AOSR1 and D164AOSR1. Conclusions: SPAK and OSR1 participate in the regulation of KCNQ1/E1 protein abundance and activity.

  16. Migraine: possible role of platelet insensitivity to prostaglandin E1 (PGE1).

    Science.gov (United States)

    Cerneca, F; de Luyk, S; Radillo, O; Simeone, R; Mangiarotti, M

    1993-01-01

    Platelet aggregation inhibition, induced by prostaglandin E1 (PGE1), was evaluated in 38 patients affected by migraine. Our data indicate a complete insensitivity to PGE1 in these subjects. The insensitivity to PGE1 leads to decreased cyclic-AMP (cAMP) levels, determining an imbalance in the inhibitory mechanism. From this observation we can suppose that the decreased affinity of PGE1-receptors, causing decreased cAMP levels, may be involved in pathogenesis of migraine.

  17. p53/E1b58kDa complex regulates adenovirus replication.

    Science.gov (United States)

    Ridgway, P J; Hall, A R; Myers, C J; Braithwaite, A W

    1997-10-27

    We have explored a role for the adenovirus (Ad5) E1b58kDa/p53 protein complex in adenovirus replication. This was done by using virus mutants containing different defects in the E1b58kDa gene and cell lines that express either a wild-type p53 protein or a mutant p53 protein. We find that infection of wild-type p53-containing cells with wild-type Ad5 causes a shutoff of p53 and alpha-actin protein synthesis by distinct mechanisms, but neither occurs in mutant p53 cells. Our data also indicate that the shutoff is dependent on formation of the p53/E1b complex and may also involve another virus protein, E4ORF6. Following from these observations we asked whether failure to form the complex resulted in impaired adenovirus replication. Our experiments showed that neither wild-type Ad5 nor the E1b mutant dl338 could replicate in cells expressing a mutant p53 protein, but that wild-type adenovirus replicated well in wild-type p53-expressing cells. Collectively, our data suggest that the interaction between p53 and the E1b58kDa protein is necessary for efficient adenovirus replication. This is the first time such a direct link between the complex and virus replication has been demonstrated. These data raise serious questions about the usefulness of E1b-defective viruses in tumor therapy.

  18. CYP2E1 Pst Ⅰ/Rsa Ⅰ polymorphism and colorectal cancer risk:A meta-analysis

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To clarify the association between CYP2E1 PstⅠ/RsaⅠ polymorphism and susceptibility to colorectal cancer.METHODS:A meta-analysis based on 10 eligible casecontrol studies involving 4979 cases and 6012 controls was carried out to summarize the data on the association between CYP2E1 RsaⅠ/PstⅠ polymorphism and colorectal cancer risk.RESULTS:In comparison of the homozygote c2c2 and c2 carriers(c1c2 + c2c2) and the homozygous wild-type genotype(c1c1),no association was found between CYP2E1 RsaⅠ/PstⅠ polymorph...

  19. Occupational Toluene Exposure Induces Cytochrome P450 2E1 mRNA Expression in Peripheral Lymphocytes

    OpenAIRE

    Mendoza-Cantú, Ania; Castorena-Torres, Fabiola; León,Mario Bermúdez de; Cisneros, Bulmaro; López-Carrillo, Lizbeth; Rojas-García, Aurora E.; Aguilar-Salinas, Alberto; Manno, Maurizio; Albores, Arnulfo

    2005-01-01

    Print workers are exposed to organic solvents, of which the systemic toxicant toluene is a main component. Toluene induces expression of cytochrome P450 2E1 (CYP2E1), an enzyme involved in its own metabolism and that of other protoxicants, including some procarcinogens. Therefore, we investigated the association between toluene exposure and the CYP2E1 response, as assessed by mRNA content in peripheral lymphocytes or the 6-hydroxychlorzoxazone (6OH-CHZ)/chlorzoxazone (CHZ) quotient (known as ...

  20. Ivermectin induces P-glycoprotein expression and function through mRNA stabilization in murine hepatocyte cell line.

    Science.gov (United States)

    Ménez, Cécile; Mselli-Lakhal, Laïla; Foucaud-Vignault, Magali; Balaguer, Patrick; Alvinerie, Michel; Lespine, Anne

    2012-01-15

    Ivermectin is widely used in human and veterinary medicine for the control of helminth infections. Ivermectin is known to interact with P-glycoprotein (P-gp/MDR1), being a good substrate and a potent inhibitor, however, the influence of ivermectin on the expression of the transporter has not been investigated. Expression of P-glycoprotein was investigated in cultured mouse hepatocytes acutely exposed to ivermectin. The two P-glycoprotein murine isoforms, Mdr1a and Mdr1b, mRNA levels were assessed by real-time RT-PCR. Ivermectin induced a clear time- and concentration-dependent up-regulation of Mdr1a and Mdr1b mRNA levels (as early as a 12-h exposure and up to 2.5-fold at 10μM). Moreover, ivermectin-treated cells displayed enhanced cellular efflux of the P-glycoprotein substrate calcein that was inhibited by the P-glycoprotein blocker valspodar, providing evidence that the ivermectin-induced P-glycoprotein was functional. The mechanisms underlying these effects were investigated. Ivermectin-mediated Mdr1 mRNA induction was independent of the two nuclear receptors CAR and PXR, which are known to be involved in drug transporters regulation. Moreover, by using reporter cell lines that detects specific ligand-activated transcription factors, we showed that ivermectin did not displayed CAR, PXR or AhR ligand activities. However, studies with actinomycin D revealed that the half-life of Mdr1a and Mdr1b mRNA were significantly prolonged by two-fold in ivermectin-treated cells suggesting a post-transcriptional mode of ivermectin regulation. This study demonstrates for the first time that ivermectin induces P-glycoprotein overexpression through post-transcriptional mRNA stabilization, thus offering insight into the mechanism of reduced therapeutic efficacy and development of ivermectin-resistant parasites.

  1. 26 CFR 31.3302(e)-1 - Successor employer.

    Science.gov (United States)

    2010-04-01

    ... TAXES AND COLLECTION OF INCOME TAX AT SOURCE EMPLOYMENT TAXES AND COLLECTION OF INCOME TAX AT SOURCE Federal Unemployment Tax Act (Chapter 23, Internal Revenue Code of 1954) § 31.3302(e)-1 Successor employer. (a) In general. In addition to the credits against the tax allowable under section 3302(a) and...

  2. Blood-brain barrier P-glycoprotein function in Alzheimer's disease.

    Science.gov (United States)

    van Assema, Daniëlle M E; Lubberink, Mark; Bauer, Martin; van der Flier, Wiesje M; Schuit, Robert C; Windhorst, Albert D; Comans, Emile F I; Hoetjes, Nikie J; Tolboom, Nelleke; Langer, Oliver; Müller, Markus; Scheltens, Philip; Lammertsma, Adriaan A; van Berckel, Bart N M

    2012-01-01

    Alzheimer's disease and suggests that decreased P-glycoprotein function may be involved in the pathogenesis of Alzheimer's disease.

  3. Methylglyoxal induces oxidative stress and mitochondrial dysfunction in osteoblastic MC3T3-E1 cells.

    Science.gov (United States)

    Suh, K S; Choi, E M; Rhee, S Y; Kim, Y S

    2014-02-01

    Methylglyoxal is a reactive dicarbonyl compound produced by glycolytic processing and identified as a precursor of advanced glycation end products. The elevated methylglyoxal levels in patients with diabetes are believed to contribute to diabetic complications, including bone defects. The objective of this study was to evaluate the effect of methylglyoxal on the function of osteoblastic MC3T3-E1 cells. The data indicated that methylglyoxal decreased osteoblast differentiation and induced osteoblast cytotoxicity. Pretreatment of MC3T3-E1 cells with aminoguanidine (a carbonyl scavenger), Trolox (an antioxidant), and cyclosporin A (a blocker of the mitochondrial permeability transition pore) prevented methylglyoxal-induced cytotoxicity in MC3T3-E1 cells. However, BAPTA/AM (an intracellular Ca(2+) chelator) and dantrolene (an inhibitor of endoplasmic reticulum Ca(2+) release) did not reverse the cytotoxic effect of methylglyoxal. Methylglyoxal increased the formation of intracellular reactive oxygen species, mitochondrial superoxide, and cardiolipin peroxidation in osteoblastic MC3T3-E1 cells. Methylglyoxal also decreased the mitochondrial membrane potential and intracellular ATP and nitric oxide levels, suggesting that carbonyl stress-induced loss of mitochondrial integrity contributes to the cytotoxicity of methylglyoxal. Furthermore, the results demonstrated that methylglyoxal induced protein adduct formation, inactivation of glyoxalase I, and activation of glyoxalase II. Aminoguanidine reversed all aforementioned effects of methylglyoxal. Taken together, these data support the notion that high methylglyoxal concentrations have detrimental effects on osteoblasts through a mechanism involving oxidative stress and mitochondrial dysfunction.

  4. Stabilization of lysosomal membrane and cell membrane glycoprotein profile by Semecarpus anacardium linn. nut milk extract in experimental hepatocellular carcinoma.

    Science.gov (United States)

    Premalatha, B; Sachdanandam, P

    2000-08-01

    Semecarpus anacardium Linn. nut milk extract administered orally at a dose of 200 mg/kg/day for 14 days exerted an in vivo stabilizing effect on lysosomal membrane and glycoprotein content in rat hepatocellular carcinoma. This was demonstrated in normal rats and in animals whose biomembranes were rendered fragile by induction of hepatocellular carcinoma with aflatoxin B(1) and subsequent treatment with Semecarpus anacardium nut extract. In this condition, the discharge of lysosomal enzymes increased significantly with a subsequent increase in glycoprotein components. The nut extract administration reversed these adverse changes to near normal in treated animals. The possible reason for this reversal is discussed. Such stabilization of biomembranes by Semecarpus anacardium nut extract may have a beneficial effect in the treatment of hepatocellular carcinoma and other cancers involving abnormal fragility of lysosomes and glycoprotein content providing the extract demonstrates safety in a full toxicity study. Copyright 2000 John Wiley & Sons, Ltd.

  5. Conglutinin binds the HIV-1 envelope glycoprotein gp 160 and inhibits its interaction with cell membrane CD4

    DEFF Research Database (Denmark)

    Andersen, Ove; Sørensen, A M; Svehag, S E

    1991-01-01

    The highly glycosylated envelope glycoprotein (gp 160) of human immunodeficiency virus (HIV) interacts with the CD4 molecule present on the membrane of CD4+ cells and is involved in the pathobiology of HIV infection. Lectins bind glycoproteins through non-covalent interactions with specific hexose...... residues. The mammalian C-type lectin bovine conglutinin was examined for its ability to interact with recombinant gp160 (rgp160) produced in vaccinia virus-infected BHK21 cells. Specific binding of conglutinin to rgp160 was demonstrated by ELISA. The interaction of bovine conglutinin with rgp160...... of the binding of rgp160 to the CD4 receptor on CEM 13 cells, as demonstrated by FACS analyses. These results indicate that conglutinin may inhibit the infection with HIV-1 through its interaction with the viral envelope glycoprotein....

  6. Inflammatory glycoproteins in cardiometabolic disorders, autoimmune diseases and cancer

    NARCIS (Netherlands)

    Connelly, Margery A.; Gruppen, Eke G.; Otvos, James D.; Dullaart, Robin P. F.

    2016-01-01

    The physiological function initially attributed to the oligosaccharide moieties or glycans on inflammatory glycoproteins was to improve protein stability. However, it is now clear that glycans play a prominent role in glycoprotein structure and function and in some cases contribute to disease

  7. Isolation and partial characterization of rat gastric mucous glycoprotein

    NARCIS (Netherlands)

    Spee-Brand, R.; Strous, G.J.A.M.; Kramer, M.F.

    1980-01-01

    Mucus glycoproteins from the rat stomach were characterized after their isolation from homogenates of the superficial gastric mucosa by equilibrium centrifugation in CsCl density gradients. Water-soluble as well as water-insoluble glycoproteins were studied. The latter were solubilized by 2-mercapto

  8. Mammalian cytochrome CYP2E1 triggered differential gene regulation in response to trichloroethylene (TCE) in a transgenic poplar.

    Science.gov (United States)

    Kang, Jun Won; Wilkerson, Hui-Wen; Farin, Federico M; Bammler, Theo K; Beyer, Richard P; Strand, Stuart E; Doty, Sharon L

    2010-08-01

    Trichloroethylene (TCE) is an important environmental contaminant of soil, groundwater, and air. Studies of the metabolism of TCE by poplar trees suggest that cytochrome P450 enzymes are involved. Using poplar genome microarrays, we report a number of putative genes that are differentially expressed in response to TCE. In a previous study, transgenic hybrid poplar plants expressing mammalian cytochrome P450 2E1 (CYP2E1) had increased metabolism of TCE. In the vector control plants for this construct, 24 h following TCE exposure, 517 genes were upregulated and 650 genes were downregulated over 2-fold when compared with the non-exposed vector control plants. However, in the transgenic CYP2E1 plant, line 78, 1,601 genes were upregulated and 1,705 genes were downregulated over 2-fold when compared with the non-exposed transgenic CYP2E1 plant. It appeared that the CYP2E1 transgenic hybrid poplar plants overexpressing mammalian CYP2E1 showed a larger number of differentially expressed transcripts, suggesting a metabolic pathway for TCE to metabolites had been initiated by activity of CYP2E1 on TCE. These results suggest that either the over-expression of the CYP2E1 gene or the abundance of TCE metabolites from CYP450 2E1 activity triggered a strong genetic response to TCE. Particularly, cytochrome p450s, glutathione S-transferases, glucosyltransferases, and ABC transporters in the CYP2E1 transgenic hybrid poplar plants were highly expressed compared with in vector controls.

  9. CYP2E1 impairs GLUT4 gene expression and function: NRF2 as a possible mediator.

    Science.gov (United States)

    Armoni, M; Harel, C; Ramdas, M; Karnieli, E

    2014-06-01

    Impaired GLUT4 function/expression in insulin target tissues is well-documented in diabetes and obesity. Cytochrome P450 isoform 2E1 (CYP2E1) induces oxidative stress, leading to impaired insulin action. CYP2E1 knockout mice are protected against high fat diet-induced insulin resistance and obesity; however the molecular mechanisms are still unclear. We examined whether CYP2E1 impairs GLUT4 gene expression and function in adipose and muscle cells. CYP2E1 overexpression in skeletal muscle-derived L6 cells inhibited insulin-stimulated Glut4 translocation and 2-deoxyglucose uptake, with the latter inhibition being blocked by vitamin E. CYP2E1 overexpression in L6 and primary rat adipose (PRA) cells suppressed GLUT4 gene expression at promoter and mRNA levels, whereas CYP2E1 silencing had opposite effects. In PRA, CYP2E1-induced suppression of GLUT4 expression was blocked by chlormethiazole (CYP2E1-specific inhibitor) and the antioxidants vitamin E and N-acetyl-l-cysteine. CYP2E1 effect was mediated by the transcription factor NF-E2-related factor 2 (NRF2), as evident from its complete reversal by a coexpressed dominant-negative, but not wild-type NRF2. GLUT4 transcription was suppressed by NRF2 overexpression, and enhanced by NRF2 silencing. Promoter and ChIP analysis showed a direct and specific binding of NRF2 to a 58-326 GLUT4 promoter region that was required to maintain CYP2E1 suppression; this binding was enhanced by CYP2E1 overexpression. We suggest a mechanism for CYP2E1 action that involves: a) suppression of GLUT4 gene expression that is mediated by NRF2; b) impairment of insulin-stimulated Glut4 translocation and function. CYP2E1 and NRF2 are introduced as negative regulators of GLUT4 expression and function in insulin-sensitive cells.

  10. Glyco-engineering in Archaea: differential N-glycosylation of the S-layer glycoprotein in a transformed Haloferax volcanii strain.

    Science.gov (United States)

    Calo, Doron; Guan, Ziqiang; Eichler, Jerry

    2011-07-01

    Archaeal glycoproteins present a variety of N-linked glycans not seen elsewhere. The ability to harness the agents responsible for this unparalleled diversity offers the possibility of generating glycoproteins bearing tailored glycans, optimized for specific functions. With a well-defined N-glycosylation pathway and available genetic tools, the haloarchaeon Haloferax volcanii represents a suitable platform for such glyco-engineering efforts. In Hfx. volcanii, the S-layer glycoprotein is modified by an N-linked pentasaccharide. In the following, S-layer glycoprotein N-glycosylation was considered in cells in which AglD, the dolichol phosphate mannose synthase involved in addition of the final residue of the pentasaccharide, was replaced by a haloarchaeal homologue of AglJ, the enzyme involved in addition of the first residue of the N-linked pentasaccharide. In the engineering strain, the S-layer glycoprotein is modified by a novel N-linked glycan not found on this reporter from the parent strain. Moreover, deletion of AglD alone and introduction of the AglJ homologue from Halobacterium salinarum, OE2528R, into the deletion strain resulted in increased biosynthesis of the novel 894 Da glycan concomitant with reduced biogenesis of the pentasaccharide normally N-linked to the S-layer glycoprotein. These findings justify efforts designed to transform Hfx. volcanii into a glyco-engineering 'workshop'.

  11. St. John's Wort reduces beta-amyloid accumulation in a double transgenic Alzheimer's disease mouse model-role of P-glycoprotein.

    Science.gov (United States)

    Brenn, Anja; Grube, Markus; Jedlitschky, Gabriele; Fischer, Andrea; Strohmeier, Barbara; Eiden, Martin; Keller, Markus; Groschup, Martin H; Vogelgesang, Silke

    2014-01-01

    The adenosine triphosphate-binding cassette transport protein P-glycoprotein (ABCB1) is involved in the export of beta-amyloid from the brain into the blood, and there is evidence that age-associated deficits in cerebral P-glycoprotein content may be involved in Alzheimer's disease pathogenesis. P-glycoprotein function and expression can be pharmacologically induced by a variety of compounds including extracts of Hypericum perforatum (St. John's Wort). To clarify the effect of St. John's Wort on the accumulation of beta-amyloid and P-glycoprotein expression in the brain, St. John's Wort extract (final hyperforin concentration 5%) was fed to 30-day-old male C57BL/6J-APP/PS1(+/-) mice over a period of 60 or 120 days, respectively. Age-matched male C57BL/6J-APP/PS1(+/-) mice receiving a St. John's Wort-free diet served as controls. Mice receiving St. John's Wort extract showed (i) significant reductions of parenchymal beta-amyloid 1-40 and 1-42 accumulation; and (ii) moderate, but statistically significant increases in cerebrovascular P-glycoprotein expression. Thus, the induction of cerebrovascular P-glycoprotein may be a novel therapeutic strategy to protect the brain from beta-amyloid accumulation, and thereby impede the progression of Alzheimer's disease.

  12. Solubilization of glycoproteins of envelope viruses by detergents

    Energy Technology Data Exchange (ETDEWEB)

    Berezin, V.E.; Zaides, V.M.; Artamsnov, A.F.; Isaeva, E.S.; Zhdanov, V.M.

    1986-11-20

    The action of a number of known ionic and nonionic detergents, as well as the new nonionic detergent MESK, on envelope viruses was investigated. It was shown that the nonionic detergents MESK, Triton X-100, and octyl-..beta..-D-glucopyranoside selectively solubilize the outer glycoproteins of the virus particles. The nonionic detergent MESK has the mildest action. Using MESK, purified glycoproteins of influenza, parainfluenza, Venezuelan equine encephalomyelitis, vesicular stomatitis, rabies, and herpes viruses were obtained. The procedure for obtaining glycoproteins includes incubation of the virus suspension with the detergent MESK, removal of subvirus structures by centrifuging, and purification of glycoproteins from detergents by dialysis. Isolated glycoproteins retain a native structure and biological activity and possess high immunogenicity. The detergent MESK is promising for laboratory tests and with respect to the production of subunit vaccines.

  13. Recent advances in the study of active endogenous retrovirus envelope glycoproteins in the mammalian placenta

    Institute of Scientific and Technical Information of China (English)

    Yufei; Zhang; Jing; Shi; Shuying; Liu

    2015-01-01

    Endogenous retroviruses(ERVs) are a component of the vertebrate genome and originate from exogenous infections of retroviruses in the germline of the host. ERVs have coevolved with their hosts over millions of years. Envelope glycoproteins of endogenous retroviruses are often expressed in the mammalian placenta, and their potential function has aroused considerable research interest, including the manipulation of maternal physiology to benefit the fetus. In most mammalian species, trophoblast fusion in the placenta is an important event, involving the formation of a multinucleated syncytiotrophoblast layer to fulfill essential fetomaternal exchange functions. The key function in this process derives from the envelope genes of endogenous retroviruses, namely syncytins, which show fusogenic properties and placenta-specific expression. This review discusses the important role of the recognized endogenous retrovirus envelope glycoproteins in the mammalian placenta.

  14. Chromosomal damage induced by human adenovirus type 12 requires expression of the E1B 55-kilodalton viral protein.

    Science.gov (United States)

    Schramayr, S; Caporossi, D; Mak, I; Jelinek, T; Bacchetti, S

    1990-01-01

    Infection of human embryonic kidney cells with adenovirus type 12 results in the induction of damage at specific (17q21-22, 1p36, 1q21, and 1q42-43) and random sites in the cellular chromosomes. A previous study by Durnam et al. (D. M. Durnam, P. P. Smith, J. C. Menninger, and J. K. McDougall, Cancer Cells 4:349-354, 1986) indicated that the expression of viral early region 1 (E1) is sufficient for the induction of damage at band 17q21-22. In the present report we used an adenovirus type 12-adenovirus type 5 recombinant with E1A hybrid sequences as well as viruses with mutations in the adenovirus type 12 E1B genes to map adenovirus type 12 E1 functions involved in the induction of genetic damage. Our results show that the expression of the E1A proteins is not sufficient for this effect. On the other hand, mutations within the E1B 55-kilodalton protein but not the E1B 19-kilodalton protein affect the ability of the virus to induce both specific and random chromosomal damage. Images PMID:2325204

  15. Effect of specific amino acid substitutions in the putative fusion peptide of structural glycoprotein E2 on Classical Swine Fever Virus replication

    Energy Technology Data Exchange (ETDEWEB)

    Fernández-Sainz, I.J. [Plum Island Animal Disease Center, ARS, USDA (United States); Largo, E. [Biophysics Unit (CSIC-UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao (Spain); Gladue, D.P.; Fletcher, P. [Plum Island Animal Disease Center, ARS, USDA (United States); O’Donnell, V. [Plum Island Animal Disease Center, ARS, USDA (United States); Plum Island Animal Disease Center, DHS, Greenport, NY 11944 (United States); Holinka, L.G. [Plum Island Animal Disease Center, ARS, USDA (United States); Carey, L.B. [Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF), E-08003 Barcelona (Spain); Lu, X. [Plum Island Animal Disease Center, DHS, Greenport, NY 11944 (United States); Nieva, J.L. [Biophysics Unit (CSIC-UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao (Spain); Borca, M.V., E-mail: manuel.borca@ars.usda.gov [Plum Island Animal Disease Center, ARS, USDA (United States)

    2014-05-15

    E2, along with E{sup rns} and E1, is an envelope glycoprotein of Classical Swine Fever Virus (CSFV). E2 is involved in several virus functions: cell attachment, host range susceptibility and virulence in natural hosts. Here we evaluate the role of a specific E2 region, {sup 818}CPIGWTGVIEC{sup 828}, containing a putative fusion peptide (FP) sequence. Reverse genetics utilizing a full-length infectious clone of the highly virulent CSFV strain Brescia (BICv) was used to evaluate how individual amino acid substitutions within this region of E2 may affect replication of BICv. A synthetic peptide representing the complete E2 FP amino acid sequence adopted a β-type extended conformation in membrane mimetics, penetrated into model membranes, and perturbed lipid bilayer integrity in vitro. Similar peptides harboring amino acid substitutions adopted comparable conformations but exhibited different membrane activities. Therefore, a preliminary characterization of the putative FP {sup 818}CPIGWTGVIEC{sup 828} indicates a membrane fusion activity and a critical role in virus replication. - Highlights: • A putative fusion peptide (FP) region in CSFV E2 protein was shown to be critical for virus growth. • Synthetic FPs were shown to efficiently penetrate into lipid membranes using an in vitro model. • Individual residues in the FP affecting virus replication were identified by reverse genetics. • The same FP residues are also responsible for mediating membrane fusion.

  16. Pumping of drugs by P-glycoprotein

    DEFF Research Database (Denmark)

    Litman, Thomas; Skovsgaard, Torben; Stein, Wilfred D

    2003-01-01

    The apparent inhibition constant, Kapp, for the blockade of P-glycoprotein (P-gp) by four drugs, verapamil, cyclosporin A, XR9576 (tariquidar), and vinblastine, was measured by studying their ability to inhibit daunorubicin and calcein-AM efflux from four strains of Ehrlich cells with different...... levels of drug resistance and P-gp content. For daunorubicin as a transport substrate, Kapp was independent of [P-gp] for verapamil but increased strictly linearly with [P-gp] for vinblastine, cyclosporin A, and XR9576. A theoretical analysis of the kinetics of drug pumping and its reversal shows...... but rather, in serial, i.e., a drug that is pumped from the cytoplasmic phase has to pass the preemptive route upon leaving the cell. Our results are consistent with the Sauna-Ambudkar two-step model for pumping by P-gp. We suggest that the vinblastine/cyclosporin A/XR9576-binding site accepts daunorubicin...

  17. Salivary agglutinin/glycoprotein-340/DMBT1

    DEFF Research Database (Denmark)

    Ligtenberg, Antoon J M; Veerman, Enno C I; Nieuw Amerongen, Arie V

    2007-01-01

    Salivary agglutinin (SAG), lung glycoprotein-340 (gp-340) and Deleted in Malignant Brain Tumours 1 (DMBT1) are three names for identical proteins encoded by the dmbt1 gene. DMBT1/SAG/gp-340 belongs to the scavenger receptor cysteine-rich (SRCR) superfamily of proteins, a superfamily of secreted...... or membrane-bound proteins with SRCR domains that are highly conserved down to sponges, the most ancient metazoa. On the one hand, DMBT1 may represent an innate defence factor acting as a pattern recognition molecule. It interacts with a broad range of pathogens, including cariogenic streptococci...... and Helicobacter pylori, influenza viruses and HIV, but also with mucosal defence proteins, such as IgA, surfactant proteins and MUC5B. Stimulation of alveolar macrophage migration, suppression of neutrophil oxidative burst and activation of the complement cascade point further to an important role...

  18. Phenomenology of heavy quarkonium radiative E1 transitions

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Hector E. [Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching (Germany)

    2016-01-22

    We present preliminary results of the evaluation of the next-to-leading-order (NLO) relativistic corrections to the heavy quarkonium electric dipole transition (E1) rate. In our evaluation we use the quark-antiquark potential up to 1/m{sup 2} corrections that includes the effective string theory expression for the long range, a review on the method to construct this potential is given. Our results compare favorable with the experiments and may provide predictions for the rates for which no experimental data is yet available.

  19. The chang’E-1 topographic atlas of the Moon

    CERN Document Server

    Li, Chunlai; Mu, Lingli; Ren, Xin; Zuo, Wei

    2016-01-01

    This atlas is based on the lunar global Digital Elevation Models (DEM) of Chang'E-1 (CE-1), and presents CCD stereo image data with digital photogrammetry. The spatial resolution of the DEM in this atlas is 500m, with horizontal accuracy of 192m and vertical accuracy of 120m. Color-shaded relief maps with contour lines are used to show the lunar topographical characteristics. The topographical data gathered by CE-1 can provide fundamental information for the study of lunar topographical, morphological and geological structures, as well as for lunar evolution research.

  20. Crossover Analysis of CHANG'E-1 Laser Altimeter Data

    Science.gov (United States)

    Hu, W.; Yue, Z.; Di, K.

    2011-08-01

    This paper presents a preliminary result of crossover analysis and adjustment of Chang'E-1(CE-1) Laser Altimeter (LAM) data of the Moon for global and regional mapping applications. During the operation of Chang'E-1 from November 28, 2007 to December 4, 2008, the laser altimeter acquired 1400 orbital profiles with about 9.12 million altimetric points. In our experiment, we derived more than 1.38 million crossovers from 1395 ground tracks covering the entire lunar surface after eliminating outliers of orbits and altimetric points. A method of least-squares crossover adjustment with a series of basis functions of time (trigonometric functions and polynomials) is developed to reconcile the LAM data by minimizing the crossover residuals globally. The normal equations are very large but sparse; therefore they are stored and solved using sparse matrix technique. In a test area (0°N~60°N, 50°W~0°W), the crossover residuals are reduced from 62.1m to 32.8m, and the quality of the DEM generated from the adjusted LAM data is improved accordingly. We will optimize the method for the global adjustment to generate a high precision consistent global DEM, which can be used as absolute control for lunar mapping with orbital images.

  1. [Glycoprotein hexoses in feces of infants with lactose intolerance].

    Science.gov (United States)

    Filippvskiĭ, G K; Klimov, L Ia

    1995-01-01

    A modified method for estimation of total glycoprotein hexoses in feces, based on their measurements in the blood serum, is presented. Sixty-six nursing children with lactose intolerance, breastfed or formula fed, were examined; formula fed babies were kept on mixtures with high and low lactose content. Glycoprotein hexose parameters were as follows (X +/- m): 13.51 +/- 1.93, 12.05 +/- 2.20, and 3.69 +/- 0.47 g/l feces. In control children without lactose intolerance (n = 33) this value was 3.6 +/- 0.79 g/l. Increased glycoprotein excretion is connected with glycocalix and small intestinal enterocyte alteration.

  2. Human broadly neutralizing antibodies to the envelope glycoprotein complex of hepatitis C virus

    DEFF Research Database (Denmark)

    Giang, Erick; Dorner, Marcus; Prentoe, Jannick C

    2012-01-01

    Hepatitis C virus (HCV) infects ∼2% of the world's population. It is estimated that there are more than 500,000 new infections annually in Egypt, the country with the highest HCV prevalence. An effective vaccine would help control this expanding global health burden. HCV is highly variable......, and an effective vaccine should target conserved T- and B-cell epitopes of the virus. Conserved B-cell epitopes overlapping the CD81 receptor-binding site (CD81bs) on the E2 viral envelope glycoprotein have been reported previously and provide promising vaccine targets. In this study, we isolated 73 human m......Abs recognizing five distinct antigenic regions on the virus envelope glycoprotein complex E1E2 from an HCV-immune phage-display antibody library by using an exhaustive-panning strategy. Many of these mAbs were broadly neutralizing. In particular, the mAb AR4A, recognizing a discontinuous epitope outside the CD81...

  3. Low temperature-dependent salmonid alphavirus glycoprotein processing and recombinant virus-like particle formation.

    Directory of Open Access Journals (Sweden)

    Stefan W Metz

    Full Text Available Pancreas disease (PD and sleeping disease (SD are important viral scourges in aquaculture of Atlantic salmon and rainbow trout. The etiological agent of PD and SD is salmonid alphavirus (SAV, an unusual member of the Togaviridae (genus Alphavirus. SAV replicates at lower temperatures in fish. Outbreaks of SAV are associated with large economic losses of ~17 to 50 million $/year. Current control strategies rely on vaccination with inactivated virus formulations that are cumbersome to obtain and have intrinsic safety risks. In this research we were able to obtain non-infectious virus-like particles (VLPs of SAV via expression of recombinant baculoviruses encoding SAV capsid protein and two major immunodominant viral glycoproteins, E1 and E2 in Spodoptera frugiperda Sf9 insect cells. However, this was only achieved when a temperature shift from 27°C to lower temperatures was applied. At 27°C, precursor E2 (PE2 was misfolded and not processed by host furin into mature E2. Hence, E2 was detected neither on the surface of infected cells nor as VLPs in the culture fluid. However, when temperatures during protein expression were lowered, PE2 was processed into mature E2 in a temperature-dependent manner and VLPs were abundantly produced. So, temperature shift-down during synthesis is a prerequisite for correct SAV glycoprotein processing and recombinant VLP production.

  4. Down-regulation of the P-glycoprotein relevant for multidrug resistance by intracellular acidification through the crosstalk of MAPK signaling pathways.

    Science.gov (United States)

    Jin, Weina; Lu, Ying; Li, Qinghua; Wang, Jian; Zhang, Hongju; Chang, Guoqiang; Lin, Yani; Pang, Tianxiang

    2014-09-01

    In our previous study, we have found that the tumor multidrug resistance mediated by P-glycoprotein could be reversed by sustained intracellular acidification through down-regulating the multidrug resistance gene 1 mRNA and P-glycoprotein expression. However, the molecular events linking the intracellular acidification and the regulation of P-glycoprotein remain unclear. In the present study, the molecular pathways involved in the regulation of P-glycoprotein expression by the intracellular acidification were investigated. We found that the P-glycoprotein expression was down-regulated by the intracellular acidification through inhibition of p38 mitogen-activated protein kinase (MAPK) and the activation of c-Jun N-terminal kinase (JNK) in the resisitant K562/DOX cells. In the sensitive K562 and HL60 cell lines, the changes of the p38 MAPK expression after the acidification are not as obvious as that of K562/DOX cells, but the activation of extracellular signal-regulated kinase (ERK) is also observed, which indicates that the down-regulation of p38 MAPK by the intracellular acidification might be the resistant cell line specific. Blockade of ERK and JNK signaling by the inhibitors or RNA interference increased p38MAPK activities suggesting that cross-talk within MAPKs is also important for this response. Our study provides the first direct evidence that the reversal of P-glycoprotein-mediated multidrug resistance by intracellular acidification is mediated by the crosstalk of MAPK signaling pathways.

  5. Glycosylation of dengue virus glycoproteins and their interactions with carbohydrate receptors: possible targets for antiviral therapy.

    Science.gov (United States)

    Idris, Fakhriedzwan; Muharram, Siti Hanna; Diah, Suwarni

    2016-07-01

    Dengue virus, an RNA virus belonging to the genus Flavivirus, affects 50 million individuals annually, and approximately 500,000-1,000,000 of these infections lead to dengue hemorrhagic fever or dengue shock syndrome. With no licensed vaccine or specific antiviral treatments available to prevent dengue infection, dengue is considered a major public health problem in subtropical and tropical regions. The virus, like other enveloped viruses, uses the host's cellular enzymes to synthesize its structural (C, E, and prM/M) and nonstructural proteins (NS1-5) and, subsequently, to glycosylate these proteins to produce complete and functional glycoproteins. The structural glycoproteins, specifically the E protein, are known to interact with the host's carbohydrate receptors through the viral proteins' N-glycosylation sites and thus mediate the viral invasion of cells. This review focuses on the involvement of dengue glycoproteins in the course of infection and the virus' exploitation of the host's glycans, especially the interactions between host receptors and carbohydrate moieties. We also discuss the recent developments in antiviral therapies that target these processes and interactions, focusing specifically on the use of carbohydrate-binding agents derived from plants, commonly known as lectins, to inhibit the progression of infection.

  6. In vivo and in vitro characterization of CYP2E1 activity in Japanese and Caucasians.

    Science.gov (United States)

    Kim, R B; Yamazaki, H; Chiba, K; O'Shea, D; Mimura, M; Guengerich, F P; Ishizaki, T; Shimada, T; Wilkinson, G R

    1996-10-01

    Chlorzoxazone's disposition after oral administration was determined in 20 young healthy Caucasian men and a similar group of Japanese men. The drug's plasma concentrations were significantly higher and its rate of elimination slower in Japanese compared to Caucasian men. Accordingly, chlorzoxazone's oral clearance was smaller (40%) in Japanese men and a similar difference (30%) was still apparent after normalizing for body weight (3.74 +/- 1.23 versus 5.05 +/- 1.41 ml.min-1.kg-1, P relationships were found between measures of CYP2E1 activity, both in vivo and in vitro, and genomic polymorphisms in the CYP2E1 gene identified by Rsal/Pstl and Dral restriction fragment length polymorphisms. Collectively, these data show an interracial difference in CYP2E1 activity. Because this enzyme is importantly involved in the activation of environmental procarcinogens, such a difference may account, in part, for the lower rate of some cancers, e.g., lung cancer, in Japanese compared to Caucasians men.

  7. Comparative Studies of Vertebrate Platelet Glycoprotein 4 (CD36

    Directory of Open Access Journals (Sweden)

    Roger S. Holmes

    2012-09-01

    Full Text Available Platelet glycoprotein 4 (CD36 (or fatty acyl translocase [FAT], or scavenger receptor class B, member 3 [SCARB3] is an essential cell surface and skeletal muscle outer mitochondrial membrane glycoprotein involved in multiple functions in the body. CD36 serves as a ligand receptor of thrombospondin, long chain fatty acids, oxidized low density lipoproteins (LDLs and malaria-infected erythrocytes. CD36 also influences various diseases, including angiogenesis, thrombosis, atherosclerosis, malaria, diabetes, steatosis, dementia and obesity. Genetic deficiency of this protein results in significant changes in fatty acid and oxidized lipid uptake. Comparative CD36 amino acid sequences and structures and CD36 gene locations were examined using data from several vertebrate genome projects. Vertebrate CD36 sequences shared 53–100% identity as compared with 29–32% sequence identities with other CD36-like superfamily members, SCARB1 and SCARB2. At least eight vertebrate CD36 N-glycosylation sites were conserved which are required for membrane integration. Sequence alignments, key amino acid residues and predicted secondary structures were also studied. Three CD36 domains were identified including cytoplasmic, transmembrane and exoplasmic sequences. Conserved sequences included N- and C-terminal transmembrane glycines; and exoplasmic cysteine disulphide residues; TSP-1 and PE binding sites, Thr92 and His242, respectively; 17 conserved proline and 14 glycine residues, which may participate in forming CD36 ‘short loops’; and basic amino acid residues, and may contribute to fatty acid and thrombospondin binding. Vertebrate CD36 genes usually contained 12 coding exons. The human CD36 gene contained transcription factor binding sites (including PPARG and PPARA contributing to a high gene expression level (6.6 times average. Phylogenetic analyses examined the relationships and potential evolutionary origins of the vertebrate CD36 gene with vertebrate

  8. Optimization of irinotecan chronotherapy with P-glycoprotein inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Filipski, Elisabeth; Berland, Elodie [INSERM, U776 “Rythmes biologiques et cancers”, CAMPUS CNRS, 7 rue Guy Môquet, F-94801 Villejuif (France); Univ Paris-Sud, UMR-S0776, Orsay F-91405 (France); Ozturk, Narin [INSERM, U776 “Rythmes biologiques et cancers”, CAMPUS CNRS, 7 rue Guy Môquet, F-94801 Villejuif (France); Univ Paris-Sud, UMR-S0776, Orsay F-91405 (France); Istanbul University Faculty of Pharmacy, Department of Pharmacology, Beyazit TR-34116, Istanbul (Turkey); Guettier, Catherine [Assistance Publique-Hôpitaux de Paris, Unité de Chronothérapie, Département de Cancérologie, Hôpital Paul Brousse, Villejuif F-94807 (France); Horst, Gijsbertus T.J. van der [Department of Genetics, Erasmus University Medical Center, 3000 CA Rotterdam (Netherlands); Lévi, Francis [INSERM, U776 “Rythmes biologiques et cancers”, CAMPUS CNRS, 7 rue Guy Môquet, F-94801 Villejuif (France); Univ Paris-Sud, UMR-S0776, Orsay F-91405 (France); Assistance Publique-Hôpitaux de Paris, Unité de Chronothérapie, Département de Cancérologie, Hôpital Paul Brousse, Villejuif F-94807 (France); and others

    2014-02-01

    The relevance of P-glycoprotein (P-gp) for irinotecan chronopharmacology was investigated in female B6D2F{sub 1} mice. A three-fold 24 h change in the mRNA expression of Abcb1b was demonstrated in ileum mucosa, with a maximum at Zeitgeber Time (ZT) 15 (p < 0.001). No rhythm was found for abcb1a in ileum mucosa, or for Abcb1a/b in Glasgow osteosarcoma (GOS), a mouse tumor cell line moderately sensitive to irinotecan. Non-tumor-bearing mice received irinotecan (50 mg/kg/day i.v. × 4 days) as a single agent or combined with P-gp inhibitor PSC833 (6.25 mg/kg/day i.p. × 4 days) at ZT3 or ZT15, respectively corresponding to the worst or the best irinotecan tolerability. Endpoints involved survival, body weight change and hematologic toxicity. Antitumor efficacy was studied in GOS-bearing mice receiving irinotecan (25, 30 or 40 mg/kg/day × 4 days) and +/− PSC833 at ZT3 or ZT15, with survival, body weight change, and tumor growth inhibition as endpoints. Non-tumor bearing mice lost an average of 17% or 9% of their body weight according to irinotecan administration at ZT3 or ZT15 respectively (p < 0.001). Dosing at ZT15 rather than ZT3 reduced mean leucopenia (9% vs 53%; p < 0.001). PSC833 aggravated irinotecan lethal toxicity from 4 to ∼ 60%. In tumor-bearing mice, body weight loss was ∼ halved in the mice on irinotecan or irinotecan–PSC833 combination at ZT15 as compared to ZT3 (p < 0.001). PSC833–irinotecan at ZT15 increased tumor inhibition by ∼ 40% as compared to irinotecan only at ZT15. In conclusion, P-gp was an important determinant of the circadian balance between toxicity and efficacy of irinotecan. - Highlights: • Irinotecan chronotolerance and chronoefficacy change as drug was applied with PSC833. • P-glycoprotein is an important player of the toxicity and efficacy of irinotecan. • Timing should be considered if chemotherapy is performed with a MDR1 inhibitor.

  9. In Silico Prediction of Human Sulfotransferase 1E1 Activity Guided by Pharmacophores from Molecular Dynamics Simulations.

    Science.gov (United States)

    Rakers, Christin; Schumacher, Fabian; Meinl, Walter; Glatt, Hansruedi; Kleuser, Burkhard; Wolber, Gerhard

    2016-01-01

    Acting during phase II metabolism, sulfotransferases (SULTs) serve detoxification by transforming a broad spectrum of compounds from pharmaceutical, nutritional, or environmental sources into more easily excretable metabolites. However, SULT activity has also been shown to promote formation of reactive metabolites that may have genotoxic effects. SULT subtype 1E1 (SULT1E1) was identified as a key player in estrogen homeostasis, which is involved in many physiological processes and the pathogenesis of breast and endometrial cancer. The development of an in silico prediction model for SULT1E1 ligands would therefore support the development of metabolically inert drugs and help to assess health risks related to hormonal imbalances. Here, we report on a novel approach to develop a model that enables prediction of substrates and inhibitors of SULT1E1. Molecular dynamics simulations were performed to investigate enzyme flexibility and sample protein conformations. Pharmacophores were developed that served as a cornerstone of the model, and machine learning techniques were applied for prediction refinement. The prediction model was used to screen the DrugBank (a database of experimental and approved drugs): 28% of the predicted hits were reported in literature as ligands of SULT1E1. From the remaining hits, a selection of nine molecules was subjected to biochemical assay validation and experimental results were in accordance with the in silico prediction of SULT1E1 inhibitors and substrates, thus affirming our prediction hypotheses.

  10. Low Cost Network Emulator with Ethernet and E1 Interfaces

    Directory of Open Access Journals (Sweden)

    Zbynek Kocur

    2010-01-01

    Full Text Available Contemporary Next Generation Networks (NGN are mainly built on the Internet Protocol (IP and Ethernet. Major challenge for emerging types of wired and wireless IP-based networks is to provide an adequate Quality of Service (QoS for different services. The quality of evaluation requires a detailed knowledge of the performance requirements for particular services and applications. The paper is primarily oriented to the end-to-end testing for the Ethernet-based terminal equipment. The low cost Ethernet network emulator was developed on the Department of Telecommunication Technology of the Faculty of Electrical Engineering of the Czech Technical University in Prague. The extension for emulation network with the E1 interfaces and TDM over IP transmission can be used with external converters.

  11. Detection of glycoproteins in the Acanthamoeba plasma membrane

    Energy Technology Data Exchange (ETDEWEB)

    Paatero, G.I.L. (Abo Akademi (Finland)); Gahmberg, C.G. (Univ. of Helsinki (Finland))

    1988-11-01

    In the present study the authors have shown that glycoproteins are present in the plasma membrane of Acanthamoeba castellanii by utilizing different radioactive labeling techniques. Plasma membrane proteins in the amoeba were iodinated by {sup 125}I-lactoperoxidase labeling and the solubilized radiolabeled glycoproteins were separated by lectin-Sepharose affinity chromatography followed by polyacrylamide gel electrophoresis. The periodate/NaB{sup 3}H{sub 4} and galactose oxidase/NaB{sup 3}H{sub 4} labeling techniques were used for labeling of surface carbohydrates in the amoeba. Several surface-labeled glycoproteins were observed in addition to a diffusely labeled region with M{sub r} of 55,000-75,000 seen on electrophoresis, which could represent glycolipids. The presence of glycoproteins in the plasma membrane of Acanthamoeba castellanii was confirmed by metabolic labeling with ({sup 35}S)methionine followed by lectin-Sepharose affinity chromatography and polyacrylamide gel electrophoresis.

  12. Mutational analysis of the hepatitis C virus E1 glycoprotein in retroviral pseudoparticles and cell-culture-derived H77/JFH1 chimeric infectious virus particles

    DEFF Research Database (Denmark)

    Russell, R S; Kawaguchi, K; Meunier, J-C

    2009-01-01

    . Retrovirus-based HCV-pseudotyped viruses (HCVpp; genotype 1a) containing Ala or Pro substitutions at conserved amino acid positions within this putative fusion peptide were generated. Mutation of conserved residues significantly reduced efficiency of HCVpp entry into Huh-7 cells. The majority of amino acid...

  13. Subcellular Localization of Rat CYP2E1 Impacts Metabolic Efficiency toward Common Substrates

    OpenAIRE

    2015-01-01

    Cytochrome P450 2E1 (CYP2E1) detoxifies or bioactivates many low molecular-weight compounds. Most knowledge about CYP2E1 activity relies on studies of the enzyme localized to endoplasmic reticulum (erCYP2E1); however, CYP2E1 undergoes transport to mitochondria (mtCYP2E1) and becomes metabolically active. We report the first comparison of in vitro steady-state kinetic profiles for erCYP2E1 and mtCYP2E1 oxidation of probe substrate 4-nitrophenol and pollutants styrene and aniline using subcellu...

  14. Data of evolutionary structure change: 1E1QA-2HLDT [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1QA-2HLDT 1E1Q 2HLD A T DLEETGRVLSIGDGIARVHGLRNVQAEEMVEFSSGLKGM...VDALVPIGRGQRELIIGDRQTGKTAVALDTILNQKRWNNGSDESKKLYCVYVAVGQKRSTVAQLVQTLEQHDAMKYSIIVAATASEAAPLQYLAPFTAASIGEWFRDN...bID> T 2HLDT ALKQVAGS

  15. Data of evolutionary structure change: 1E1RC-2HLDT [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1RC-2HLDT 1E1R 2HLD C T ADTSVDLEETGRVLSIGDGIARVHGLRNVQAEEMVEFSS...VQTGLKAVDALVPIGRGQRELIIGDRQTGKTAVALDTILNQKRWNNGSDESKKLYCVYVAVGQKRSTVAQLVQTLEQHDAMKYSIIVAATASEAAPLQYLAPFTAASI... 2HLD T 2HLDT AAFAQ--

  16. Data of evolutionary structure change: 1E1RA-2HLDT [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1RA-2HLDT 1E1R 2HLD A T DLEETGRVLSIGDGIARVHGLRNVQAEEMVEFSSGLKGM...VDALVPIGRGQRELIIGDRQTGKTAVALDTILNQKRWNNGSDESKKLYCVYVAVGQKRSTVAQLVQTLEQHDAMKYSIIVAATASEAAPLQYLAPFTAASIGEWFRDN...bChain>T 2HLDT ALKQVAGSLKLFL

  17. Structure of Pyrazole Derivatives Impact their Affinity, Stoichiometry, and Cooperative Interactions for CYP2E1 Complexes

    Science.gov (United States)

    Hartman, Jessica H.; Bradley, Amber M.; Laddusaw, Ryan M; Perry, Martin D.; Miller, Grover P.

    2013-01-01

    CYP2E1 plays a critical role in detoxication and carcinogenic activation of drugs, pollutants, and dietary compounds; however, these metabolic processes can involve poorly characterized cooperative interactions that compromise the ability to understand and predict CYP2E1 metabolism. Herein, we employed an array of ten azoles with an emphasis on pyrazoles to establish the selectivity of catalytic and cooperative CYP2E1 sites through binding and catalytic studies. Spectral binding studies for monocyclic azoles suggested two binding events, while bicyclic azoles suggested one. Pyrazole had moderate affinity toward the CYP2E1 catalytic site that improved when a methyl group was introduced at either position 3 or 4. The presence of methyl groups simultaneously at positions 3 and 5 blocked binding, and a phenyl group at position 3 did not improve binding affinity. In contrast, pyrazole fusion to a benzene or cyclohexane ring greatly increased affinity. The consequences of these binding events on CYP2E1 catalysis were studied through inhibition studies with 4-nitrophenol, a substrate known to bind both sites. Most pyrazoles shared a common mixed cooperative inhibition mechanism in which pyrazole binding rescued CYP2E1 from substrate inhibition. Overall, inhibitor affinities toward the CYP2E1 catalytic site were similar to those reported in binding studies, and the same trend was observed for binding at the cooperative site. Taken together, these studies identified key structural determinants in the affinity and stoichiometry of azole interactions with CYP2E1 and consequences on catalysis that further advance an understanding of the relationship between structure and function for this enzyme. PMID:23811196

  18. KDN-containing glycoprotein from loach skin mucus.

    Science.gov (United States)

    Nakagawa, H; Hama, Y; Sumi, T; Li, S C; Li, Y T

    2001-01-01

    It has been widely recognized that the mucus coat of fish plays a variety of important physical, chemical, and physiological functions. One of the major constituents of the mucus coat is mucus glycoprotein. We found that sialic acids in the skin mucus of the loach, Misgurnus anguillicaudatus, consisted predominantly of KDN. Subsequently, we isolated KDN-containing glycoprotein from loach skin mucus and characterized its chemical nature and structure. Loach mucus glycoprotein was purified from the Tris-HCl buffer extract of loach skin mucus by DEAE-cellulose chromatography, Nuclease P1 treatment, and Sepharose CL-6B gel filtration. The purified mucus glycoprotein was found to contain 38.5 KDN, 0.5% NeuAc, 25.0% GalNAc, 3.5% Gal, 0.5% GlcNAc and 28% amino acids. Exhaustive Actinase digestion of the glycoprotein yielded a glycopeptide with a higher sugar content and higher Thr and Ser contents. The molecular size of this glycopeptide was approximately 1/12 of the intact glycoprotein. These results suggest that approximately 11 highly glycosylated polypeptide units are linked in tandem through nonglycosylated peptides to form the glycoporotein molecule. The oligosaccharide alditols liberated from the loach mucus glycoprotein by alkaline borohydride treatment were separated by Sephadex G-25 gel filtration and HPLC. The purified sugar chains were analyzed b --> 6GalNAc-ol, KDNalpha2 --> 3(GalNAcbeta1 --> 14)GalNAc-ol, KDNalpha2 --> 6(GalNAcalpha1 --> 3)GalNAc-ol, KDNalpha2 --> 6(Gal3alpha1--> 3)GalNAc-ol, and NeuAcalpha2 --> 6Gal NAc-ol. It is estimated that one loach mucus glycoprotein molecule contains more than 500 KDN-containing sugar chains that are linked to Thr and Ser residues of the protein core through GalNAc.

  19. Improved Monosynaptic Neural Circuit Tracing Using Engineered Rabies Virus Glycoproteins

    Directory of Open Access Journals (Sweden)

    Euiseok J. Kim

    2016-04-01

    Full Text Available Monosynaptic rabies virus tracing is a unique and powerful tool used to identify neurons making direct presynaptic connections onto neurons of interest across the entire nervous system. Current methods utilize complementation of glycoprotein gene-deleted rabies of the SAD B19 strain with its glycoprotein, B19G, to mediate retrograde transsynaptic spread across a single synaptic step. In most conditions, this method labels only a fraction of input neurons and would thus benefit from improved efficiency of transsynaptic spread. Here, we report newly engineered glycoprotein variants to improve transsynaptic efficiency. Among them, oG (optimized glycoprotein is a codon-optimized version of a chimeric glycoprotein consisting of the transmembrane/cytoplasmic domain of B19G and the extracellular domain of rabies Pasteur virus strain glycoprotein. We demonstrate that oG increases the tracing efficiency for long-distance input neurons up to 20-fold compared to B19G. oG-mediated rabies tracing will therefore allow identification and study of more complete monosynaptic input neural networks.

  20. Pollen tube access to the ovule is mediated by glycoprotein secretion on the obturator of apple (Malus × domestica, Borkh).

    Science.gov (United States)

    Losada, Juan M; Herrero, Maria

    2017-04-01

    Within the ovary, the obturator bridges the pathway of the pollen tube from the style to the ovule. Despite its widespread presence among flowering plants, its function has only been studied in a handful of species, and the molecules involved in pollen tube-obturator cross-talk have not been explored hitherto. This work evaluates the involvement of glucans and glycoproteins on pollen tube growth in the obturator of apple flowers ( Malus × domestica) . Pollen tube kinetics were sequentially examined in the pistil and related to changes occurring on the obturator using histochemistry and inmunocytochemistry. To discriminate between changes in the obturator induced by pollen tubes from those developmentally regulated, both pollinated and unpollinated pistils were examined. Pollen tube growth rates were slow in the stigma, faster in the style and slow again in the ovary. The arrival of pollen tubes at the obturator was concomitant with the secretion of proteins, saccharides and glycoprotein epitopes belonging to extensins and arabinogalactan proteins (AGPs). While some of these secretions - extensins and AGPs labelled by JIM13 - were developmentally regulated, others - AGPs labelled by JIM8 - were elicited by the presence of pollen tubes. Following pollen tube passage, all these glycoproteins were depleted. The results show a timely secretion of glycoproteins on the obturator surface concomitant with pollen tube arrival at this structure. The fact that their secretion is depleted following pollen tube passage strongly suggests their role in regulating pollen tube access to the ovule. Remarkably, both the regulation of the secretion of the different glycoproteins, as well as their association with the performance of pollen tubes exhibit similarities with those observed in the stigma, in line with their common developmental origin.

  1. Nucleic acid-binding glycoproteins which solubilize nucleic acids in dilute acid: re-examination of the Ustilago maydis glycoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Unrau, P.; Champ, D.R.; Young, J.L.; Grant, C.E.

    1980-01-01

    Holloman reported the isolation from Ustilago maydis of a glycoprotein which prevented the precipitation of nucleic acids in cold 5% trichloroacetic acid. Two glycoprotein fractions from U. maydis with this nucleic acid-solubilizing activity were isolated in our laboratory using improved purification procedures. The activity was not due to nuclease contamination. The glycoproteins are distinguished by: their ability to bind to concanavalin A-Sepharose; their differential binding to double- and single-stranded deoxyribonucleic acid, and to ribonucleic acid; their molecular weights (46,000 and 69,000); and the relative amounts present in growing versus nongrowing cells. Both fractions required sulfhydryl-reducing conditions for optimal yields, specific activity, and stability. Nucleic acid binding was cooperative, the minimum number of glycoproteins required to make a native T7 DNA molecule soluble in dilute acid being estimated at 2 and 15, respectively.

  2. P-glycoprotein targeted nanoscale drug carriers

    KAUST Repository

    Li, Wengang

    2013-02-01

    Multi-drug resistance (MDR) is a trend whereby tumor cells exposed to one cytotoxic agent develop cross-resistance to a range of structurally and functionally unrelated compounds. P -glycoprotein (P -gp) efflux pump is one of the mostly studied drug carrying processes that shuttle the drugs out of tumor cells. Thus, P -gp inhibitors have attracted a lot of attention as they can stop cancer drugs from being pumped out of target cells with the consumption of ATP. Using quantitive structure activity relationship (QSAR), we have successfully synthesized a series of novel P -gp inhibitors. The obtained dihydropyrroloquinoxalines series were fully characterized and then tested against bacterial and tumor assays with over-expressed P -gps. All compounds were bioactive especially compound 1c that had enhanced antibacterial activity. Furthermore, these compounds were utilized as targeting vectors to direct drug delivery vehicles such as silica nanoparticles (SNPs) to cancerous Hela cells with over expressed P -gps. Cell uptake studies showed a successful accumulation of these decorated SNPs in tumor cells compared to undecorated SNPs. The results obtained show that dihydropyrroloquinoxalines constitute a promising drug candidate for targeting cancers with MDR. Copyright © 2013 American Scientific Publishers All rights reserved.

  3. [Genetic polymorphism of cytochrome P450 2E1 and the risk of nasopharyngeal carcinoma].

    Science.gov (United States)

    Ben Chaaben, Arij; Abaza, Hajer; Douik, Hayet; Chaouch, Leila; Ayari, Fayza; Ouni, Nesrine; Mamoghli, Tasnim; Ben Guezella, Dorra; Mejri, Rachida; Harzallah, Latifa; Guemira, Fethi

    2015-12-01

    Cytochrome P450 2E1 (CYP2E1) is a detoxifying enzyme that belongs to the phase I metabolism of xenobiotics. This enzyme is encoded by a highly polymorphic gene whose common polymorphism corresponds to the substitution of cytosine (C) and thymine (T) at position -1019 (rs2031920). This polymorphism has been identified in several cancers including nasopharyngeal cancer (NPC). The study involved 124 patients with nasopharyngeal carcinoma, compared with 166 healthy controls. The presence or absence of the polymorphism is determined by PCR-RFLP. The frequency comparison between the two groups is determined by the χ(2) test. The analysis of our results showed a significant difference between the two groups regarding the mutant genotype (C2/C2) (5% vs. 0.5%, P=0.04) and has a risk factor for NPC in Tunisia (OR=8.39; CI 95% [0.99-388.1]). Also, the C2 allele was significantly associated with the group of patients than the control group (6% vs. 2%, P=0.016) and increased three times the risk of NPC in Tunisia (OR=2.99, CI 95% [1.12-8.79]). Our results confirm the results reported in other populations and emphasize the importance of the involvement of this gene in the development of detoxification of the NPC, which seems more and more strongly associated with environmental factors.

  4. Laurus nobilis L. Seed Extract Reveals Collateral Sensitivity in Multidrug-Resistant P-Glycoprotein-Expressing Tumor Cells.

    Science.gov (United States)

    Saab, Antoine M; Guerrini, Alessandra; Zeino, Maen; Wiench, Benjamin; Rossi, Damiano; Gambari, Roberto; Sacchetti, Gianni; Greten, Henry Johannes; Efferth, Thomas

    2015-01-01

    The frequent failure of standard cancer chemotherapy requires the development of novel drugs capable of killing otherwise drug-resistant tumors. Here, we have investigated a chloroform extract of Laurus nobilis seeds. Fatty acids and 23 constituents of the volatile fraction were identified by gas chromotography/flame ionization detection (GC/FID) and gas chromatography/mass spectrometry (GC/MS), in good agreement with (1)H NMR (nuclear magnetic resonance) spectrum. Multidrug-resistant P-glycoprotein-expressing CEM/ADR5000 leukemia cells were hypersensitive (collaterally sensitive) toward this extract compared to drug-sensitive CCRF-CEM cells, whereas CEM/ADR5000 cells were 2586-fold resistant to doxorubicin as control drug. Collateral sensitivity was verified by measurement of apoptotic cells by flow cytometry. The log10IC50 values of 3 compounds in the extract (limonene, eucalyptol, oleic acid) did not correlate with mRNA expression of the P-glycoprotein-coding ABCB1/MDR1 gene and accumulation of the P-glycoprotein substrate rhodamine in the NCI panel of tumor cell lines. A microarray-based profile of 20 genes predicted resistance to doxorubicin and 7 other anticancer drugs involved in the multidrug resistance phenotype but not to limonene, eucalyptol and oleic acid. In conclusion, our results show that Laurus nobilis seed extract is suitable to kill multidrug-resistant P-glycoprotein expressing tumor cells.

  5. Estrogen sulfotransferase/SULT1E1 promotes human adipogenesis.

    Science.gov (United States)

    Ihunnah, Chibueze A; Wada, Taira; Philips, Brian J; Ravuri, Sudheer K; Gibbs, Robert B; Kirisci, Levent; Rubin, J Peter; Marra, Kacey G; Xie, Wen

    2014-05-01

    Estrogen sulfotransferase (EST/SULT1E1) is known to catalyze the sulfoconjugation and deactivation of estrogens. The goal of this study is to determine whether and how EST plays a role in human adipogenesis. By using human primary adipose-derived stem cells (ASCs) and whole-fat tissues from the abdominal subcutaneous fat of obese and nonobese subjects, we showed that the expression of EST was low in preadipocytes but increased upon differentiation. Overexpression and knockdown of EST in ASCs promoted and inhibited differentiation, respectively. The proadipogenic activity of EST in humans was opposite to the antiadipogenic effect of the same enzyme in rodents. Mechanistically, EST promoted adipogenesis by deactivating estrogens. The proadipogenic effect of EST can be recapitulated by using an estrogen receptor (ER) antagonist or ERα knockdown. In contrast, activation of ER in ASCs inhibited adipogenesis by decreasing the recruitment of the adipogenic peroxisome proliferator-activated receptor γ (PPARγ) onto its target gene promoters, whereas ER antagonism increased the recruitment of PPARγ to its target gene promoters. Linear regression analysis revealed a positive correlation between the expression of EST and body mass index (BMI), as well as a negative correlation between ERα expression and BMI. We conclude that EST is a proadipogenic factor which may serve as a druggable target to inhibit the turnover and accumulation of adipocytes in obese patients.

  6. E1 and M1 strength functions at low energy

    Directory of Open Access Journals (Sweden)

    Schwengner Ronald

    2017-01-01

    Full Text Available We report photon-scattering experiments using bremsstrahlung at the γELBE facility of Helmholtz-Zentrum Dresden-Rossendorf and using quasi-monoenergetic, polarized γ beams at the HIγS facility of the Triangle Universities Nuclear Laboratory in Durham. To deduce the photoabsorption cross sections at high excitation energy and high level density, unresolved strength in the quasicontinuum of nuclear states has been taken into account. In the analysis of the spectra measured by using bremsstrahlung at γELBE, we perform simulations of statistical γ-ray cascades using the code γDEX to estimate intensities of inelastic transitions to low-lying excited states. Simulated average branching ratios are compared with model-independent branching ratios obtained from spectra measured by using monoenergetic γ beams at HIγS. E1 strength in the energy region of the pygmy dipole resonance is discussed in nuclei around mass 90 and in xenon isotopes. M1 strength in the region of the spin-flip resonance is also considered for xenon isotopes. The dipole strength function of 74Ge deduced from γELBE experiments is compared with the one obtained from experiments at the Oslo Cyclotron Laboratory. The low-energy upbend seen in the Oslo data is interpreted as M1 strength on the basis of shell-model calculations.

  7. Data of evolutionary structure change: 1E1QC-2HLDA [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1QC-2HLDA 1E1Q 2HLD C A ADTSVDLEETGRVLSIGDGIARVHGLRNVQAEEMVEFSS...ELFYKGIRPAINVGLSVSRVGSAAQTRAMKQVAGTMKLELAQYREVAAFAQFGSDLDAATQQLLSRGVRLTELLKQGQYSPMAIEEQVAVIYAGVRGYLDKLEPSKIT...RPAINVGLSVSRVGSAAQVKALKQVAGSLKLFLAQYREVAAFAQS--DLDASTKQTLVRGERLTQLLKQNQYSPLATEEQV...> 0 2HLD A 2HLDA AFAQS--DLDA...ain> 1E1Q C 1E1QC AFAQFGSDLDA

  8. Role of zona pellucida glycoproteins during fertilization in humans.

    Science.gov (United States)

    Gupta, Satish Kumar

    2015-04-01

    In the last decade, scientific investigations pertaining to the role of zona pellucida (ZP) glycoproteins during fertilization in humans have led to new insights. This has been achieved using purified native/recombinant human zona proteins and transgenic mice expressing human ZP glycoproteins. The proposed model in mice of ZP glycoprotein-3 (ZP3) acting as primary sperm receptor and ZP glycoprotein-2 (ZP2) as secondary sperm receptor has been modified for sperm-egg binding in humans. ZP glycoprotein-1 (ZP1), ZP3, and ZP glycoprotein-4 (ZP4) have been shown to bind to the capacitated human sperm. ZP2 binds to the acrosome-reacted human spermatozoa. Further, the eggs obtained from transgenic mice expressing human ZP2 alone or in conjunction with other human instead of mouse zona proteins showed binding of human sperm, suggesting that ZP2 might also play a role in sperm-egg binding. This function has been mapped to a domain corresponding to amino acid residues 51-144 of ZP2. In contrast to mice, where ZP3 is the primary agonist for inducing the acrosome reaction, in humans, the acrosome reaction can be mediated by ZP1, ZP3, and ZP4. The effect of mutations in the genes encoding zona proteins on the ZP morphology and infertility has not been established. Further, the role of autoantibodies against ZP in women with 'unexplained infertility' leading to poor outcome of in vitro fertilization is currently controversial and needs further investigations. Understanding the role of ZP glycoproteins during human fertilization facilitates the development of new contraceptives and strategies to overcome the problem of infertility.

  9. Genotype and allele frequencies of polymorphic cytochromes P450 CYP1A2 and CYP2E1 in Mexicans.

    Science.gov (United States)

    Mendoza-Cantú, Ania; Castorena-Torres, Fabiola; Bermudez, Mario; Martínez-Hernández, Roberto; Ortega, Arturo; Salinas, Juan E; Albores, Arnulfo

    2004-01-01

    CYP1A2 and CYP2E1 are two of the main cytochrome P450 isoforms involved in the metabolism of commonly used drugs and xenobiotic compounds considered to be responsible for or possible participants in the development of several human diseases. Individual susceptibility to developing these pathologies relies, among other factors, on genetic polymorphism which depends on ethnic differences, as the frequency of mutant genotypes varies in different human populations. Thus the aim of this study was to investigate the frequency of CYP1A2 5'-flanking region and CYP2E1 Rsa I/Pst I polymorphisms in Mexicans by PCR-RFLP methods. The DNA of 159 subjects was analysed and mutant allele frequencies of 30% for CYP2E1 Rsa I/Pst I sites and 43% for CYP1A2 5'-flanking region were found. These frequencies are higher than those previously reported for other human populations.

  10. Role of cytochrome P450 2E1 in the metabolism of acrylamide and acrylonitrile in mice.

    Science.gov (United States)

    Sumner, S C; Fennell, T R; Moore, T A; Chanas, B; Gonzalez, F; Ghanayem, B I

    1999-11-01

    Acrylonitrile (AN) and acrylamide (AM) are commonly used in the synthesis of plastics and polymers. In rodents, AM and AN are metabolized to the epoxides glycidamide and cyanoethylene oxide, respectively. The aim of this study was to determine the role of cytochrome P450 in the metabolism of AM and AN in vivo. Wild-type (WT) mice, WT mice pretreated with aminobenzotriazole (ABT, 50 mg/kg ip, 2 h pre-exposure), and mice devoid of cytochrome P450 2E1 (P450 2E1-null) were treated with 50 mg/kg [(13)C]AM po. WT mice and P450 2E1-null mice were treated with 2.5 or 10 mg/kg [(13)C]AN po. Urine was collected for 24 h, and metabolites were characterized using (13)C NMR. WT mice excreted metabolites derived from the epoxides and from direct GSH conjugation with AM or AN. Only metabolites derived from direct GSH conjugation with AM or AN were observed in the urine from ABT-pretreated WT mice and P450 2E1-null mice. On the basis of evaluation of urinary metabolites at these doses, these data suggest that P450 2E1 is possibly the only cytochrome P450 enzyme involved in the metabolism of AM and AN in mice, that inhibiting total P450 activity does not result in new pathways of non-P450 metabolism of AM, and that mice devoid of P450 2E1 do not excrete metabolites of AM or AN that would be produced by oxidation by other cytochrome P450s. P450 2E1-null mice may be an appropriate model for the investigation of the role of oxidative metabolism in the toxicity or carcinogenicity of these compounds.

  11. Selective identification and differentiation of N- and O-linked oligosaccharides in glycoproteins by liquid chromatography-mass spectrometry.

    OpenAIRE

    Carr, S. A.; Huddleston, M. J.; Bean, M. F.

    1993-01-01

    A mass spectrometry method has been developed for selective detection of glycopeptides at the low (< or = 25) picomole level during chromatography of glycoprotein digests and for differentiation of O-linked from N-linked oligosaccharides. The technique involves observation of diagnostic sugar oxonium-ion fragments, particularly the HexNAc+ fragment at m/z 204, from collisionally excited glycopeptides. Collision-induced fragmentation can be accomplished in either of two regions of a triple qua...

  12. The E1 beta-subunit of pyruvate dehydrogenase is surface-expressed in Lactobacillus plantarum and binds fibronectin.

    Science.gov (United States)

    Vastano, Valeria; Salzillo, Marzia; Siciliano, Rosa A; Muscariello, Lidia; Sacco, Margherita; Marasco, Rosangela

    2014-01-01

    Lactobacillus plantarum is among the species with a probiotic activity. Adhesion of probiotic bacteria to host tissues is an important principle for strain selection, because it represents a crucial step in the colonization process of either pathogens or commensals. Most bacterial adhesins are proteins, and a major target for them is fibronectin, an extracellular matrix glycoprotein. In this study we demonstrate that PDHB, a component of the pyruvate dehydrogenase complex, is a factor contributing to fibronectin-binding in L. plantarum LM3. By means of fibronectin overlay immunoblotting assay, we identified a L. plantarum LM3 surface protein with apparent molecular mass of 35 kDa. Mass spectrometric analysis shows that this protein is the pyruvate dehydrogenase E1 beta-subunit (PDHB). The corresponding pdhB gene is located in a 4-gene cluster encoding pyruvate dehydrogenase. In LM3-B1, carrying a null mutation in pdhB, the 35 kDa adhesin was not anymore detectable by immunoblotting assay. Nevertheless, the pdhB null mutation did not abolish pdhA, pdhC, and pdhD transcription in LM3-B1. By adhesion assays, we show that LM3-B1 cells bind to immobilized fibronectin less efficiently than wild type cells. Moreover, we show that pdhB expression is negatively regulated by the CcpA protein and is induced by bile.

  13. The role of reactive oxygen species (ROS and cytochrome P-450 2E1 in the generation of carcinogenic etheno-DNA adducts

    Directory of Open Access Journals (Sweden)

    Kirsten Linhart

    2014-01-01

    Full Text Available Exocyclic etheno-DNA adducts are mutagenic and carcinogenic and are formed by the reaction of lipidperoxidation (LPO products such as 4-hydoxynonenal or malondialdehyde with DNA bases. LPO products are generated either via inflammation driven oxidative stress or via the induction of cytochrome P-450 2E1 (CYP2E1. In the liver CYP2E1 is induced by various compounds including free fatty acids, acetone and ethanol. Increased levels of CYP2E1 and thus, oxidative stress are observed in the liver of patients with non-alcoholic steatohepatitis (NASH as well as in the chronic alcoholic. In addition, chronic ethanol ingestion also increases CYP2E1 in the mucosa of the oesophagus and colon. In all these tissues CYP2E1 correlates significantly with the levels of carcinogenic etheno-DNA adducts. In contrast, in patients with non-alcoholic steatohepatitis (NASH hepatic etheno-DNA adducts do not correlate with CYP2E1 indicating that in NASH etheno-DNA adducts formation is predominately driven by inflammation rather than by CYP2E1 induction. Since etheno-DNA adducts are strong mutagens producing various types of base pair substitution mutations as well as other types of genetic damage, it is strongly believed that they are involved in ethanol mediated carcinogenesis primarily driven by the induction of CYP2E1.

  14. Characterization of Autoantibodies against the E1 Subunit of Branched-Chain 2-Oxoacid Dehydrogenase in Patients with Primary Biliary Cirrhosis

    Directory of Open Access Journals (Sweden)

    Tsutomu Mori

    2012-01-01

    Full Text Available Primary biliary cirrhosis (PBC is characterized by antimitochondrial antibodies (AMAs that react with the lipoyl-containing E2 subunits of 2-oxoacid dehydrogenase complexes such as BCOADC and PDC. The lipoyl domains of E2 contain the major epitopes essential for immunopathology. However, the non-lipoyl-containing E1 subunits are also frequently targeted. Since anti-E1 antibodies always appear in combination with anti-E2 antibodies, the mechanisms underlying the autoimmunity against E1 may be linked to, but distinct from, those against E2. Here, we demonstrate that intermolecular and intramolecular determinant spreading underlies the autoimmunity against E1. We performed characterizations and epitope mapping for anti-BCOADC-E1 antibodies from both the intermolecular and intramolecular points of view. The antibody reactivities form a cluster against the BCOADC complex that is distinct from that against the PDC complex, and the anti-BCOADC-E1 antibodies arise as part of the cluster against the BCOADC complex. Multiple epitopes are present on the surface of the BCOADC-E1 molecule, and the major epitope overlaps with the active center. Sera with anti-BCOADC-E1 antibodies strongly inhibited the enzyme activity. These findings suggest that the E1 subunit as part of the native BCOADC complex is an immunogen, and that determinant spreading is involved in the pathogenesis of AMA production.

  15. Expression and Characterization of HIV-1 Envelope Glycoprotein in Pichia Pastoris

    Institute of Scientific and Technical Information of China (English)

    ZHAO Li-hui; YU Xiang-hui; JIANG Chun-lai; WU Yong-ge; SHEN Jia-cong; KONG Wei

    2008-01-01

    To obtain a sufficient amount of glycoprotein for further studying the structure and function of HIV-1 envelope glycoprotein, amplified and modified HIV-1 envelope glycoprotein gene which recombined subtypes(850amino acids) from Guangxi in China was inserted into Pichiapastoris expression vector pPICZaB; then the recombinant plasmid was transported into the yeast cells to induce the expression of Env protein with methanol. The results of SDS-PAGE and Western blot indicate that the envelope glycoprotein could be expressed in Pichia pastoris with productions of a 120000 glycoprotein and a 41000 glycoprotein, which showed satisfactory immunogenicity by indirect ELISA.

  16. Cooperativity in CYP2E1 metabolism of acetaminophen and styrene mixtures.

    Science.gov (United States)

    Hartman, Jessica H; Letzig, Lynda G; Roberts, Dean W; James, Laura P; Fifer, E Kim; Miller, Grover P

    2015-10-01

    Risk assessment for exposure to mixtures of drugs and pollutants relies heavily on in vitro characterization of their bioactivation and/or metabolism individually and extrapolation to mixtures assuming no interaction. Herein, we demonstrated that in vitro CYP2E1 metabolic activation of acetaminophen and styrene mixtures could not be explained through the Michaelis-Menten mechanism or any models relying on that premise. As a baseline for mixture studies with styrene, steady-state analysis of acetaminophen oxidation revealed a biphasic kinetic profile that was best described by negative cooperativity (Hill coefficient=0.72). The best-fit mechanism for this relationship involved two binding sites with differing affinities (Ks=830μM and Kss=32mM). Introduction of styrene inhibited that reaction less than predicted by simple competition and thus provided evidence for a cooperative mechanism within the mixture. Likewise, acetaminophen acted through a mixed-type inhibition mechanism to impact styrene epoxidation. In this case, acetaminophen competed with styrene for CYP2E1 (Ki=830μM and Ksi=180μM for catalytic and effector sites, respectively) and resulted in cooperative impacts on binding and catalysis. Based on modeling of in vivo clearance, cooperative interactions between acetaminophen and styrene resulted in profoundly increased styrene activation at low styrene exposure levels and therapeutic acetaminophen levels. Current Michaelis-Menten based toxicological models for mixtures such as styrene and acetaminophen would fail to detect this concentration-dependent relationship. Hence, future studies must assess the role of alternate CYP2E1 mechanisms in bioactivation of compounds to improve the accuracy of interpretations and predictions of toxicity.

  17. Discovery and Characterization of Phage Display-Derived Human Monoclonal Antibodies against RSV F Glycoprotein.

    Directory of Open Access Journals (Sweden)

    Zhifeng Chen

    Full Text Available Respiratory syncytial virus (RSV is a leading cause of lower respiratory tract infection in infants, the elderly and in immunosuppressed populations. The vast majority of neutralizing antibodies isolated from human subjects target the RSV fusion (F glycoprotein, making it an attractive target for the development of vaccines and therapeutic antibodies. Currently, Synagis® (palivizumab is the only FDA approved antibody drug for the prevention of RSV infection, and there is a great need for more effective vaccines and therapeutics. Phage display is a powerful tool in antibody discovery with the advantage that it does not require samples from immunized subjects. In this study, Morphosys HuCAL GOLD® phage libraries were used for panning against RSV prefusion and postfusion F proteins. Panels of human monoclonal antibodies (mAbs against RSV F protein were discovered following phage library panning and characterized. Antibodies binding specifically to prefusion or postfusion F proteins and those binding both conformations were identified. 3B1 is a prototypic postfusion F specific antibody while 2E1 is a prototypic prefusion F specific antibody. 2E1 is a potent broadly neutralizing antibody against both RSV A and B strains. Epitope mapping experiments identified a conformational epitope spanning across three discontinuous sections of the RSV F protein, as well as critical residues for antibody interaction.

  18. Proteolysis of specific porcine zona pellucida glycoproteins by boar acrosin.

    Science.gov (United States)

    Dunbar, B S; Dudkiewicz, A B; Bundman, D S

    1985-04-01

    The morphologic and biochemical effects on the structure and constituent glycoproteins of the zona pellucida (ZP) by a specific sperm enzyme, acrosin, and a nonsperm enzyme, trypsin, have been evaluated. Intact porcine ZP matricies, exposed to either acrosin or trypsin, were analyzed microscopically. Changes in specific glycoproteins were monitored by high-resolution two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and the silver-based color stain, GELCODE. Although these enzymes did not alter the macroscopic properties of the ZP matrix, the 2D-PAGE ZP protein patterns were markedly altered. The high molecular weight glycoprotein families (II and III) were sensitive to proteolytic digestion, whereas the major glycoprotein family (I) of the porcine zona was only partially proteolyzed by acrosin and trypsin. Furthermore, it was demonstrated that acrosin had unique substrate specificity compared to that of trypsin, since the ZP peptide patterns were found to be different. These studies are the first to demonstrate which integral glycoproteins of the native porcine ZP matrix are specifically proteolyzed by acrosin from the homologous species and that this proteolysis occurs without the dissolution of the native porcine matrix.

  19. Glycoprotein labeling with click chemistry (GLCC) and carbohydrate detection.

    Science.gov (United States)

    Wu, Zhengliang L; Huang, Xinyi; Burton, Andrew J; Swift, Karl A D

    2015-08-14

    Molecular labeling and detection techniques are essential to research in life science. Here, a method for glycoprotein labeling/carbohydrate detection through glycan replacement, termed glycoprotein labeling with click chemistry (GLCC), is described. In this method, a glycoprotein is first treated with specific glycosidases to remove certain sugar residues, a procedure that creates acceptor sites for a specific glycosyltransferase. A 'clickable' monosaccharide is then installed onto these sites by the glycosyltransferase. This modified glycoprotein is then conjugated to a reporter molecule using a click chemistry reaction. For glycoproteins that already contain vacant glycosylation sites, deglycosylation is not needed before the labeling step. As a demonstration, labeling on fetal bovine fetuin, mouse immunoglobulin IgG and bacterial expressed human TNFα and TNFβ are shown. Compared to traditional ways of protein labeling, labeling at glycosylation sites with GLCC is considerably more specific and less likely to have adverse effects, and, when utilized as a method for carbohydrate detection, this method is also highly specific and sensitive.

  20. P-glycoprotein acts as an immunomodulator during neuroinflammation.

    Directory of Open Access Journals (Sweden)

    Gijs Kooij

    Full Text Available BACKGROUND: Multiple sclerosis is an inflammatory demyelinating disease of the central nervous system in which autoreactive myelin-specific T cells cause extensive tissue damage, resulting in neurological deficits. In the disease process, T cells are primed in the periphery by antigen presenting dendritic cells (DCs. DCs are considered to be crucial regulators of specific immune responses and molecules or proteins that regulate DC function are therefore under extensive investigation. We here investigated the potential immunomodulatory capacity of the ATP binding cassette transporter P-glycoprotein (P-gp. P-gp generally drives cellular efflux of a variety of compounds and is thought to be involved in excretion of inflammatory agents from immune cells, like DCs. So far, the immunomodulatory role of these ABC transporters is unknown. METHODS AND FINDINGS: Here we demonstrate that P-gp acts as a key modulator of adaptive immunity during an in vivo model for neuroinflammation. The function of the DC is severely impaired in P-gp knockout mice (Mdr1a/1b-/-, since both DC maturation and T cell stimulatory capacity is significantly decreased. Consequently, Mdr1a/1b -/- mice develop decreased clinical signs of experimental autoimmune encephalomyelitis (EAE, an animal model for multiple sclerosis. Reduced clinical signs coincided with impaired T cell responses and T cell-specific brain inflammation. We here describe the underlying molecular mechanism and demonstrate that P-gp is crucial for the secretion of pro-inflammatory cytokines such as TNF-alpha and IFN-gamma. Importantly, the defect in DC function can be restored by exogenous addition of these cytokines. CONCLUSIONS: Our data demonstrate that P-gp downmodulates DC function through the regulation of pro-inflammatory cytokine secretion, resulting in an impaired immune response. Taken together, our work highlights a new physiological role for P-gp as an immunomodulatory molecule and reveals a possible

  1. Multiple Drug Transport Pathways through Human P-Glycoprotein.

    Science.gov (United States)

    McCormick, James W; Vogel, Pia D; Wise, John G

    2015-07-21

    P-Glycoprotein (P-gp) is a plasma membrane efflux pump that is commonly associated with therapy resistances in cancers and infectious diseases. P-gp can lower the intracellular concentrations of many drugs to subtherapeutic levels by translocating them out of the cell. Because of the broad range of substrates transported by P-gp, overexpression of P-gp causes multidrug resistance. We reported previously on dynamic transitions of P-gp as it moved through conformations based on crystal structures of homologous ABCB1 proteins using in silico targeted molecular dynamics techniques. We expanded these studies here by docking transport substrates to drug binding sites of P-gp in conformations open to the cytoplasm, followed by cycling the pump through conformations that opened to the extracellular space. We observed reproducible transport of two substrates, daunorubicin and verapamil, by an average of 11-12 Å through the plane of the membrane as P-gp progressed through a catalytic cycle. Methylpyrophosphate, a ligand that should not be transported by P-gp, did not show this movement through P-gp. Drug binding to either of two subsites on P-gp appeared to determine the initial pathway used for drug movement through the membrane. The specific side-chain interactions with drugs within each pathway seemed to be, at least in part, stochastic. The docking and transport properties of a P-gp inhibitor, tariquidar, were also studied. A mechanism of inhibition by tariquidar that involves stabilization of an outward open conformation with tariquidar bound in intracellular loops or at the drug binding domain of P-gp is presented.

  2. Alternative promoter usage of the membrane glycoprotein CD36

    Directory of Open Access Journals (Sweden)

    Whatling Carl

    2006-03-01

    Full Text Available Abstract Background CD36 is a membrane glycoprotein involved in a variety of cellular processes such as lipid transport, immune regulation, hemostasis, adhesion, angiogenesis and atherosclerosis. It is expressed in many tissues and cell types, with a tissue specific expression pattern that is a result of a complex regulation for which the molecular mechanisms are not yet fully understood. There are several alternative mRNA isoforms described for the gene. We have investigated the expression patterns of five alternative first exons of the CD36 gene in several human tissues and cell types, to better understand the molecular details behind its regulation. Results We have identified one novel alternative first exon of the CD36 gene, and confirmed the expression of four previously known alternative first exons of the gene. The alternative transcripts are all expressed in more than one human tissue and their expression patterns vary highly in skeletal muscle, heart, liver, adipose tissue, placenta, spinal cord, cerebrum and monocytes. All alternative first exons are upregulated in THP-1 macrophages in response to oxidized low density lipoproteins. The alternative promoters lack TATA-boxes and CpG islands. The upstream region of exon 1b contains several features common for house keeping gene and monocyte specific gene promoters. Conclusion Tissue-specific expression patterns of the alternative first exons of CD36 suggest that the alternative first exons of the gene are regulated individually and tissue specifically. At the same time, the fact that all first exons are upregulated in THP-1 macrophages in response to oxidized low density lipoproteins may suggest that the alternative first exons are coregulated in this cell type and environmental condition. The molecular mechanisms regulating CD36 thus appear to be unusually complex, which might reflect the multifunctional role of the gene in different tissues and cellular conditions.

  3. Analysis of cosmid clones of nuclear DNA from Trypanosome brucei shows that the genes for variant surface glycoproteins are clustered in the genome.

    NARCIS (Netherlands)

    D. Valerio (Dinko); T. de Lange; P. Borst (Piet); F.G. Grosveld (Frank); L.H.T. van der Ploeg

    1982-01-01

    textabstractTrypanosoma brucei contains more than a hundred genes coding for the different variant surface glycoproteins (VSGs). Activation of some of these genes involves the duplication of the gene (the basic copy or BC) and transposition of the duplicate to an expression site (yielding the expres

  4. Structure, dynamics, and interaction of Mycobacterium tuberculosis (Mtb DprE1 and DprE2 examined by molecular modeling, simulation, and electrostatic studies.

    Directory of Open Access Journals (Sweden)

    Isha Bhutani

    Full Text Available The enzymes decaprenylphosphoryl-β-D-ribose oxidase (DprE1 and decaprenylphosphoryl-β-D-ribose-2-epimerase (DprE2 catalyze epimerization of decaprenylphosporyl ribose (DPR todecaprenylphosporyl arabinose (DPA and are critical for the survival of Mtb. Crystal structures of DprE1 so far reported display significant disordered regions and no structural information is known for DprE2. We used homology modeling, protein threading, molecular docking and dynamics studies to investigate the structural and dynamic features of Mtb DprE1 and DprE2 and DprE1-DprE2 complex. A three-dimensional model for DprE2 was generated using the threading approach coupled with ab initio modeling. A 50 ns simulation of DprE1 and DprE2 revealed the overall stability of the structures. Principal Component Analysis (PCA demonstrated the convergence of sampling in both DprE1 and DprE2. In DprE1, residues in the 269-330 area showed considerable fluctuation in agreement with the regions of disorder observed in the reported crystal structures. In DprE2, large fluctuations were detected in residues 95-113, 146-157, and 197-226. The study combined docking and MD simulation studies to map and characterize the key residues involved in DprE1-DprE2 interaction. A 60 ns MD simulation for DprE1-DprE2 complex was also performed. Analysis of data revealed that the docked complex is stabilized by H-bonding, hydrophobic and ionic interactions. The key residues of DprE1 involved in DprE1-DprE2 interactions belong to the disordered region. We also examined the docked complex of DprE1-BTZ043 to investigate the binding pocket of DprE1 and its interactions with the inhibitor BTZ043. In summary, we hypothesize that DprE1-DprE2 interaction is crucial for the synthesis of DPA and DprE1-DprE2 complex may be a new therapeutic target amenable to pharmacological validation. The findings have important implications in tuberculosis (TB drug discovery and will facilitate drug development efforts against

  5. B(E1) Strengths from Coulomb Excitation of 11Be

    CERN Document Server

    Summers, N C; Ashwood, N I; Bouchat, V; Catford, W N; Clarke, N M; Curtis, N; Freer, M; Fulton, B R; Hanappe, F; Labiche, M; Lecouey, J L; Lemmon, R C; Mahboub, D; Ninane, A; Normand, G; Nunes, F M; Orr, N A; Pain, S D; Soic, N; Stuttgé, L; Thompson, I J; Timis, C N; Winfield, J S; Ziman, V

    2007-01-01

    The $B$(E1;$1/2^+\\to1/2^-$) strength for $^{11}$Be has been extracted from intermediate energy Coulomb excitation measurements, over a range of beam energies using a new reaction model, the extended continuum discretized coupled channels (XCDCC) method. In addition, a measurement of the excitation cross section for $^{11}$Be+$^{208}$Pb at 38.6 MeV/nucleon is reported. The $B$(E1) strength of 0.105(12) e$^2$fm$^2$ derived from this measurement is consistent with those made previously at 60 and 64 MeV/nucleon, i n contrast to an anomalously low result obtained at 43 MeV/nucleon. By coupling a multi-configuration description of the projectile structure with realistic reaction theory, the XCDCC model provides for the first time a fully quantum mechanical description of Coulomb excitation. The XCDCC calculations reveal that the excitation process involves significant contributions from nuclear, continuum, and higher-order effects. An analysis of the present and two earlier intermediate energy measurements yields a...

  6. Processing of virus-specific glycoproteins of varicella zoster virus

    Energy Technology Data Exchange (ETDEWEB)

    Namazue, J.; Campo-Vera, H.; Kitamura, K.; Okuno, T.; Yamanishi, K.

    1985-05-01

    Monoclonal antibodies to varicella zoster virus (VZV) glycoproteins were used to study the processing of three glycoproteins with molecular weights of 83K-94K (gp 2), 64K (gp 3), and 55K (gp 5). Immunoprecipitation experiments performed with VZV-infected cells, pulse labeled with (/sup 3/H)glucosamine in the presence of tunicamycin, suggest that O-linked oligosaccharide is present on the glycoprotein of gp 2. Use of the enzyme endo-beta-N-acetylglucosaminidase H revealed that the fully processed form of gp 3 had high-mannose type and that of gp 5 had only complex type of N-linked oligosaccharides. Experiments with monensin suggest that the precursor form (116K) of gp 3 is cleaved during the processing from Golgi apparatus to cell surface membrane. The extension of O-linked oligosaccharide chain and the complex type of N-linked oligosaccharide chains also occurs during this processing.

  7. Silencing of P-glycoprotein increases mortality in temephos-treated Aedes aegypti larvae.

    Science.gov (United States)

    Figueira-Mansur, J; Ferreira-Pereira, A; Mansur, J F; Franco, T A; Alvarenga, E S L; Sorgine, M H F; Neves, B C; Melo, A C A; Leal, W S; Masuda, H; Moreira, M F

    2013-12-01

    Re-emergence of vector-borne diseases such as dengue and yellow fever, which are both transmitted by the Aedes aegypti mosquito, has been correlated with insecticide resistance. P-glycoproteins (P-gps) are ATP-dependent efflux pumps that are involved in the transport of substrates across membranes. Some of these proteins have been implicated in multidrug resistance (MDR). In this study, we identified a putative P-glycoprotein in the Ae. aegypti database based on its significantly high identity with Anopheles gambiae, Culex quinquefasciatus, Drosophila melanogaster and human P-gps. The basal ATPase activity of ATP-binding cassette transporters in larvae was significantly increased in the presence of MDR modulators (verapamil and quinidine). An eightfold increase in Ae. aegypti P-gp (AaegP-gp) gene expression was detected in temephos-treated larvae as determined by quantitative PCR. To analyse the potential role of AaegP-gp in insecticide efflux, a temephos larvicide assay was performed in the presence of verapamil. The results showed an increase of 24% in temephos toxicity, which is in agreement with the efflux reversing effect. RNA interference (RNAi)-mediated silencing of the AaegP-gp gene caused a significant increase in temephos toxicity (57%). In conclusion, we have demonstrated for the first time in insects that insecticide-induced P-gp expression can be involved in the modulation of insecticide efflux.

  8. Human platelet glycoprotein Ia. One component is only expressed on the surface of activated platelets and may be a granule constituent

    Energy Technology Data Exchange (ETDEWEB)

    Bienz, D.; Clemetson, K.J.

    1989-01-05

    Glycoprotein Ia (GP Ia) is a relatively minor component of human blood platelets thought to be a receptor involved in collagen-induced platelet activation. However, some difficulties exist with the definition of this glycoprotein. The expression of GP Ia on resting (prostacyclin analogue-treated) and thrombin-activated platelets was compared by surface labeling with /sup 125/I-lactoperoxidase. Intact platelets or platelets solubilized in sodium dodecyl sulfate were labeled with periodate/(/sup 3/H)NaBH/sub 4/. Analysis on two-dimensional isoelectric focusing/sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels showed that GP Ia is very poorly labeled in resting platelets. After activation a new spot (GP Ia*) appears with the same relative molecular mass as GP Ia under reducing conditions. GP Ia and Ia* can be clearly separated by two-dimensional nonreduced/reduced gel electrophoresis. Therefore, two glycoproteins which have been termed GP Ia exist in platelets with similar molecular weight and pI under reducing conditions. One of these (GP Ia*) is only surface-labeled when platelets are activated, indicating that it is only exposed on the surface of activated platelets. Supernatant from activated platelets contains this glycoprotein as well as other granule components. This glycoprotein is missing in platelets from two patients with collagen-response defects.

  9. The Deacetylase SIRT1 Regulates the Replication Properties of Human Papillomavirus 16 E1 and E2.

    Science.gov (United States)

    Das, Dipon; Smith, Nathan; Wang, Xu; Morgan, Iain M

    2017-05-15

    Human papillomaviruses (HPV) replicate their genomes in differentiating epithelium using the viral proteins E1 and E2 in association with host proteins. While the roles of E1 and E2 in this process are understood, the host factors involved and how they interact with and regulate E1-E2 are not. Our previous work identified the host replication and repair factor TopBP1 as an E2 partner protein essential for optimal E1-E2 replication and for the viral life cycle. The role of TopBP1 in host DNA replication is regulated by the class III deacetylase SIRT1; activation of the DNA damage response prevents SIRT1 deacetylation of TopBP1, resulting in a switch from DNA replication to repair functions for this protein and cell cycle arrest. Others have demonstrated an essential role for SIRT1 in regulation of the HPV31 life cycle; here, we report that SIRT1 can directly regulate HPV16 E1-E2-mediated DNA replication. SIRT1 is part of the E1-E2 DNA replication complex and is recruited to the viral origin of replication in an E1-E2-dependent manner. CRISPR/Cas9 was used to generate C33a clones with undetectable SIRT1 expression and lack of SIRT1 elevated E1-E2 DNA replication, in part due to increased acetylation and stabilization of the E2 protein in the absence of SIRT1. The results demonstrate that SIRT1 is a member of, and can regulate, the HPV16 replication complex. We discuss the potential role of this protein in the viral life cycle.IMPORTANCE HPV are causative agents in a number of human diseases, and currently only the symptoms of these diseases are treated. To identify novel therapeutic approaches for combating these diseases, the viral life cycle must be understood in more detail. This report demonstrates that a cellular enzyme, SIRT1, is part of the HPV16 DNA replication complex and is brought to the viral genome by the viral proteins E1 and E2. Using gene editing technology (CRISPR/Cas9), the SIRT1 gene was removed from cervical cancer cells. The consequence of this

  10. Square-wave voltammetry assays for glycoproteins on nanoporous gold

    Science.gov (United States)

    Pandey, Binod; Bhattarai, Jay K.; Pornsuriyasak, Papapida; Fujikawa, Kohki; Catania, Rosa; Demchenko, Alexei V.; Stine, Keith J.

    2014-01-01

    Electrochemical enzyme-linked lectinsorbent assays (ELLA) were developed using nanoporous gold (NPG) as a solid support for protein immobilization and as an electrode for the electrochemical determination of the product of the reaction between alkaline phosphatase (ALP) and p-aminophenyl phosphate (p-APP), which is p-aminophenol (p-AP). Glycoproteins or concanavalin A (Con A) and ALP conjugates were covalently immobilized onto lipoic acid self-assembled monolayers on NPG. The binding of Con A – ALP (or soybean agglutinin – ALP) conjugate to glycoproteins covalently immobilized on NPG and subsequent incubation with p-APP substrate was found to result in square-wave voltammograms whose peak difference current varied with the identity of the glycoprotein. NPG presenting covalently bound glycoproteins was used as the basis for a competitive electrochemical assay for glycoproteins in solution (transferrin and IgG). A kinetic ELLA based on steric hindrance of the enzyme-substrate reaction and hence reduced enzymatic reaction rate after glycoprotein binding is demonstrated using immobilized Con A–ALP conjugates. Using the immobilized Con A-ALP conjugate, the binding affinity of immunoglobulin G (IgG) was found to be 105 nM, and that for transferrin was found to be 650 nM. Minimal interference was observed in the presence of 5 mg mL−1 BSA as a model serum protein in both the kinetic and competitive ELLA. Inhibition studies were performed with methyl D-mannoside for the binding of TSF and IgG to Con A-ALP; IC50 values were found to be 90 μM and 286 μM, respectively. Surface coverages of proteins were estimated using solution depletion and the BCA protein concentration assay. PMID:24611035

  11. Removal of N-Linked Glycosylations at Acidic pH by PNGase A Facilitates Hydrogen/Deuterium Exchange Mass Spectrometry Analysis of N-Linked Glycoproteins

    DEFF Research Database (Denmark)

    Jensen, Pernille Foged; Comamala Grau, Gerard; Trelle, Morten Beck

    2016-01-01

    Protein glycosylation is the most frequent post-translational modification and is present on more than 50% of eukaryotic proteins. Glycosylation covers a wide subset of modifications involving many types of complex oligosaccharide structures, making structural analysis of glycoproteins...... and their glycans challenging for most analytical techniques. Hydrogen/deuterium exchange monitored by mass spectrometry is a sensitive technique for investigation of protein conformational dynamics of complex heterogeneous proteins in solution. N-linked glycoproteins however pose a challenge for HDX-MS. HDX...... for analysis of the conformational dynamics of N-linked glycoproteins that utilizes the enzyme PNGase A for deglycosylation of labeled peptic N-linked glycopeptides at HDX quench conditions, i.e., acidic pH and low temperature. PNGase A-based deglycosylation is thus performed after labeling (post...

  12. A Functional Henipavirus Envelope Glycoprotein Pseudotyped Lentivirus Assay System

    Directory of Open Access Journals (Sweden)

    Broder Christopher C

    2010-11-01

    Full Text Available Abstract Background Hendra virus (HeV and Nipah virus (NiV are newly emerged zoonotic paramyxoviruses discovered during outbreaks in Queensland, Australia in 1994 and peninsular Malaysia in 1998/9 respectively and classified within the new Henipavirus genus. Both viruses can infect a broad range of mammalian species causing severe and often-lethal disease in humans and animals, and repeated outbreaks continue to occur. Extensive laboratory studies on the host cell infection stage of HeV and NiV and the roles of their envelope glycoproteins have been hampered by their highly pathogenic nature and restriction to biosafety level-4 (BSL-4 containment. To circumvent this problem, we have developed a henipavirus envelope glycoprotein pseudotyped lentivirus assay system using either a luciferase gene or green fluorescent protein (GFP gene encoding human immunodeficiency virus type-1 (HIV-1 genome in conjunction with the HeV and NiV fusion (F and attachment (G glycoproteins. Results Functional retrovirus particles pseudotyped with henipavirus F and G glycoproteins displayed proper target cell tropism and entry and infection was dependent on the presence of the HeV and NiV receptors ephrinB2 or B3 on target cells. The functional specificity of the assay was confirmed by the lack of reporter-gene signals when particles bearing either only the F or only G glycoprotein were prepared and assayed. Virus entry could be specifically blocked when infection was carried out in the presence of a fusion inhibiting C-terminal heptad (HR-2 peptide, a well-characterized, cross-reactive, neutralizing human mAb specific for the henipavirus G glycoprotein, and soluble ephrinB2 and B3 receptors. In addition, the utility of the assay was also demonstrated by an examination of the influence of the cytoplasmic tail of F in its fusion activity and incorporation into pseudotyped virus particles by generating and testing a panel of truncation mutants of NiV and HeV F

  13. Multiple genes encode the major surface glycoprotein of Pneumocystis carinii

    DEFF Research Database (Denmark)

    Kovacs, J A; Powell, F; Edman, J C;

    1993-01-01

    this antigen is a good candidate for development as a vaccine to prevent or control P. carinii infection. We have cloned and sequenced seven related but unique genes encoding the major surface glycoprotein of rat P. carinii. Partial amino acid sequencing confirmed the identity of these genes. Based on Southern...... hydrophobic region at the carboxyl terminus. The presence of multiple related msg genes encoding the major surface glycoprotein of P. carinii suggests that antigenic variation is a possible mechanism for evading host defenses. Further characterization of this family of genes should allow the development...

  14. Metabolic inactivation of resolvin E1 and stabilization of its anti-inflammatory actions.

    Science.gov (United States)

    Arita, Makoto; Oh, Sungwhan F; Chonan, Tomomichi; Hong, Song; Elangovan, Siva; Sun, Yee-Ping; Uddin, Jasim; Petasis, Nicos A; Serhan, Charles N

    2006-08-11

    The resolvins (Rv) are lipid mediators derived from omega-3 polyunsaturated fatty acids that act within a local inflammatory milieu to stop leukocyte recruitment and promote resolution. Resolvin E1 (RvE1; (5S,12R,18R)-trihydroxy-6Z,8E,10E,14Z,16E-eicosapentaenoic acid) is an oxygenase product derived from omega-3 eicosapentaenoic acid that displays potent anti-inflammation/pro-resolution actions in vivo. Here, we determined whether oxidoreductase enzymes catalyze the conversion of RvE1 and assessed the biological activity of the RvE1 metabolite. With NAD+ as a cofactor, recombinant 15-hydroxyprostaglandin dehydrogenase acted as an 18-hydroxyl dehydrogenase to form 18-oxo-RvE1. In the murine lung, dehydrogenation of the hydroxyl group at carbon 18 position to form 18-oxo-RvE1 represented the major initial metabolic route for RvE1. At a concentration where RvE1 potently reduced polymorphonuclear leukocyte (PMN) recruitment in zymosan-induced peritonitis, 18-oxo-RvE1 was devoid of activity. In human neutrophils, carbon 20 hydroxylation of RvE1 was the main route of conversion. An RvE1 analog, i.e. 19-(p-fluorophenoxy)-RvE1, was synthesized that resisted rapid metabolic inactivation and proved to retain biological activity reducing PMN infiltration and pro-inflammatory cytokine/chemokine production in vivo. These results established the structure of a novel RvE1 initial metabolite, indicating that conversion of RvE1 to the oxo product represents a mode of RvE1 inactivation. Moreover, the designed RvE1 analog, which resisted further metabolism/inactivation, could be a useful tool to evaluate the actions of RvE1 in complex disease models.

  15. Occupational Toluene Exposure Induces Cytochrome P450 2E1 mRNA Expression in Peripheral Lymphocytes

    Science.gov (United States)

    Mendoza-Cantú, Ania; Castorena-Torres, Fabiola; de León, Mario Bermúdez; Cisneros, Bulmaro; López-Carrillo, Lizbeth; Rojas-García, Aurora E.; Aguilar-Salinas, Alberto; Manno, Maurizio; Albores, Arnulfo

    2006-01-01

    Print workers are exposed to organic solvents, of which the systemic toxicant toluene is a main component. Toluene induces expression of cytochrome P450 2E1 (CYP2E1), an enzyme involved in its own metabolism and that of other protoxicants, including some procarcinogens. Therefore, we investigated the association between toluene exposure and the CYP2E1 response, as assessed by mRNA content in peripheral lymphocytes or the 6-hydroxychlorzoxazone (6OH-CHZ)/chlorzoxazone (CHZ) quotient (known as CHZ metabolic ratio) in plasma, and the role of genotype (5′-flanking region RsaI/PstI polymorphic sites) in 97 male print workers. The geometric mean (GM) of toluene concentration in the air was 52.80 ppm (10–760 ppm); 54% of the study participants were exposed to toluene concentrations that exceeded the maximum permissible exposure level (MPEL). The GM of urinary hippuric acid at the end of a work shift (0.041 g/g creatinine) was elevated relative to that before the shift (0.027 g/g creatinine; p < 0.05). The GM of the CHZ metabolic ratio was 0.33 (0–9.3), with 40% of the subjects having ratios below the GM. However, the average CYP2E1 mRNA level in peripheral lymphocytes was 1.07 (0.30–3.08), and CYP2E1 mRNA levels within subjects correlated with the toluene exposure ratio (environmental toluene concentration:urinary hippuric acid concentration) (p = 0.014). Genotype did not alter the association between the toluene exposure ratio and mRNA content. In summary, with further validation, CYP2E1 mRNA content in peripheral lymphocytes could be a sensitive and noninvasive biomarker for the continuous monitoring of toluene effects in exposed persons. PMID:16581535

  16. Genotype and allelic frequencies of CYP2E1*5B polymorphism in the southwest population of Iran

    Directory of Open Access Journals (Sweden)

    Fatemeh Zanganeh

    2014-10-01

    Full Text Available Background: Cytochrome P450 2E1 (CYP2E1 is a main enzyme which plays a major role in activating and detoxifying many xenobiotics, carcinogens and drugs. Available studies suggest that CYP2E1 single nucleotide polymorphisms (SNPs are involved in the risk of developing certain cancers after exposure to carcinogens. The purpose of the present study was to assess genotype and allele frequencies of polymorphic CYP2E1*5B in the Iranian population. Material and Methods: This study was performed on 200 healthy individuals (female: 100, male: 100 in medical laboratories of Ahvaz during 2011. The CYP2E1 *5B (rs3813867 G-1293C assessment was carried out using PCR-RFLP method. The data were analyzed with ĸ2 and hardy-Weinberg Equation statistically methods. Results: The frequency of *1A/*1A (c1/c1, *1A/*5B (c1/c2 and *5B/*5B (c2/c2 genotypes was computed 97, 3 and 0 percent, respectively. The frequency of *1A (c1 and *5B (c2 alleles was computed 98.5 and 1.5 percent, respectively. No statistically significant difference was between two genders (p>0.05. Conclusion: The genotype distribution and allele frequencies of CYP2E1*5B polymorphism were similar to Turkish and some of the European populations. However, there are significant interethnic differences when the Iranian population is compared with the Eastern Asian, American and some of the European populations. The allelic distribution of this polymorphism did not vary with gender.

  17. Occupational toluene exposure induces cytochrome P450 2E1 mRNA expression in peripheral lymphocytes.

    Science.gov (United States)

    Mendoza-Cantú, Ania; Castorena-Torres, Fabiola; Bermúdez de León, Mario; Cisneros, Bulmaro; López-Carrillo, Lizbeth; Rojas-García, Aurora E; Aguilar-Salinas, Alberto; Manno, Maurizio; Albores, Arnulfo

    2006-04-01

    Print workers are exposed to organic solvents, of which the systemic toxicant toluene is a main component. Toluene induces expression of cytochrome P450 2E1 (CYP2E1), an enzyme involved in its own metabolism and that of other protoxicants, including some procarcinogens. Therefore, we investigated the association between toluene exposure and the CYP2E1 response, as assessed by mRNA content in peripheral lymphocytes or the 6-hydroxychlorzoxazone (6OH-CHZ)/chlorzoxazone (CHZ) quotient (known as CHZ metabolic ratio) in plasma, and the role of genotype (5 -flanking region RsaI/PstI polymorphic sites) in 97 male print workers. The geometric mean (GM) of toluene concentration in the air was 52.80 ppm (10-760 ppm); 54% of the study participants were exposed to toluene concentrations that exceeded the maximum permissible exposure level (MPEL). The GM of urinary hippuric acid at the end of a work shift (0.041 g/g creatinine) was elevated relative to that before the shift (0.027 g/g creatinine; p < 0.05). The GM of the CHZ metabolic ratio was 0.33 (0-9.3), with 40% of the subjects having ratios below the GM. However, the average CYP2E1 mRNA level in peripheral lymphocytes was 1.07 (0.30-3.08), and CYP2E1 mRNA levels within subjects correlated with the toluene exposure ratio (environmental toluene concentration:urinary hippuric acid concentration) (p = 0.014). Genotype did not alter the association between the toluene exposure ratio and mRNA content. In summary, with further validation, CYP2E1 mRNA content in peripheral lymphocytes could be a sensitive and noninvasive biomarker for the continuous monitoring of toluene effects in exposed persons.

  18. Short-term treatment with alcohols causes hepatic steatosis and enhances acetaminophen hepatotoxicity in Cyp2e1(-/-) mice.

    Science.gov (United States)

    Sinclair, J F; Szakacs, J G; Wood, S G; Walton, H S; Bement, J L; Gonzalez, F J; Jeffery, E H; Wrighton, S A; Bement, W J; Sinclair, P R

    2000-10-15

    CYP2E1 has been reported to have an essential role in alcohol-mediated increases in hepatic steatosis and acetaminophen hepatotoxicity. We found that pretreatment of Cyp2e1(-/-) mice with ethanol plus isopentanol, the predominant alcohols in alcoholic beverages, for 7 days resulted in micro- and macrovesicular steatosis in the livers of all mice, as well as a dramatic increase in acetaminophen hepatotoxicity. In Cyp2e1(-/-) mice administered up to 600 mg acetaminophen/kg alone and euthanized 7 h later, there was no increase in serum levels of ALT. In Cyp2e1(-/-) mice pretreated with ethanol and isopentanol, subsequent exposure to 400 or 600 mg acetaminophen/kg resulted in centrilobular necrosis in all mice with maximal elevation in serum levels of ALT. Acetaminophen-mediated liver damage was similar in males and females. Hepatic microsomal levels of APAP activation in untreated females were similar to those in males treated with the alcohols. However, the females, like the males, required pretreatment with the alcohols in order to increase APAP hepatotoxicity. These findings suggest that, in the Cyp2e1(-/-) mice, the alcohol-mediated increase in acetaminophen hepatotoxicity involves the contribution of other factors, in addition to induction of CYP(s) that activate acetaminophen. Alternatively, CYP-mediated activation of acetaminophen measured in vitro may not reflect the actual activity in vivo. Our findings that a 7-day treatment with ethanol and isopentanol causes extensive hepatic steatosis and increases acetaminophen hepatotoxicity in Cyp2e(-/-) mice indicate that CYP2E1 is not essential for either response.

  19. Data of evolutionary structure change: 1E1QC-2HLDT [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1QC-2HLDT 1E1Q 2HLD C T ADTSVDLEETGRVLSIGDGIARVHGLRNVQAEEMVEFSS...VQTGLKAVDALVPIGRGQRELIIGDRQTGKTAVALDTILNQKRWNNGSDESKKLYCVYVAVGQKRSTVAQLVQTLEQHDAMKYSIIVAATASEAAPLQYLAPFTAASI...yChain> 2HLD T 2HLDT VAAFA---QDLD

  20. Data of evolutionary structure change: 1E1QB-2HLDT [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1QB-2HLDT 1E1Q 2HLD B T DLEETGRVLSIGDGIARVHGLRNVQAEEMVEFSSGLKGM...SDRLVKEGELVKRTGNIVDVPVGPGLLGRVVDALGNPIDGKGPIDAAGRSRAQVKAPGILPRRSVHEPVQTGLKAVDALVPIGRGQRELIIGDRQTGKTAVALDT...dbChain> 2HLDT ALKQVAGSLKLFL 2HLD T 2HLDT VAAFAQDLDAST

  1. Data of evolutionary structure change: 1E1RB-2HLDT [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1RB-2HLDT 1E1R 2HLD B T DLEETGRVLSIGDGIARVHGLRNVQAEEMVEFSSGLKGM...SDRLVKEGELVKRTGNIVDVPVGPGLLGRVVDALGNPIDGKGPIDAAGRSRAQVKAPGILPRRSVHEPVQTGLKAVDALVPIGRGQRELIIGDRQTGKTAVALDT...T 2HLDT ALKQVAGSLKLFL2HLD T 2HLDT VAAFAQDLDAST

  2. A note on inextensible flows of partially and pseudo null curves in E_1^4

    OpenAIRE

    Yuzbasi, Zuhal Kucukarslan; Bektas, Mehmet

    2013-01-01

    In this paper, we study inextensible flows of partially null and pseudo null curves in E_1^4. We give neccessary and sufficent conditions for inextensible flows of partially null and pseudo null curves in E_1^4

  3. Data of evolutionary structure change: 1E1RC-2HLDA [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1RC-2HLDA 1E1R 2HLD C A ADTSVDLEETGRVLSIGDGIARVHGLRNVQAEEMVEFSS...ELFYKGIRPAINVGLSVSRVGSAAQTRAMKQVAGTMKLELAQYREVAAFAQFGSDLDAATQQLLSRGVRLTELLKQGQYSPMAIEEQVAVIYAGVRGYLDKLEPSKIT...RPAINVGLSVSRVGSAAQVKALKQVAGSLKLFLAQYREVAAFAQS--DLDASTKQTLVRGERLTQLLKQNQYSPLATEEQV...fEVID> 0 2HLD A 2HLDA AFAQS--DLDAS GGG -- HH

  4. Immune systems in animals involve complex combi- nations of ...

    African Journals Online (AJOL)

    spamer

    Immune systems in animals involve complex combi- nations of humoral and ..... R. S., Söderhäll, K. and B. A. Weeks-Perkins (Eds). Fair. Haven, New Jersey; SOS ... Analysis of Octopus vulgaris hemolymph containing a glycoprotein with blood ...

  5. Parental Involvement

    OpenAIRE

    Ezra S Simon

    2008-01-01

    This study was conducted in Ghana to investigate, (1) factors that predict parental involvement, (2) the relationship between parental home and school involvement and the educational achievement of adolescents, (3) the relationship between parental authoritativeness and the educational achievement of adolescent students, (4) parental involvement serving as a mediator between their authoritativeness and the educational achievement of the students, and (5) whether parental involvement decreases...

  6. Structural and quantitative comparison of cerebrospinal fluid glycoproteins in Alzheimer's disease patients and healthy individuals.

    NARCIS (Netherlands)

    Sihlbom, C.; Davidsson, P.; Sjogren, M.; Wahlund, L.O.; Nilsson, C.L.

    2008-01-01

    Glycoproteins in cerebrospinal fluid (CSF) are altered in Alzheimer's Disease (AD) patients compared to control individuals. We have utilized albumin depletion prior to 2D gel electrophoresis to enhance glycoprotein concentration for image analysis as well as structural glycoprotein determination wi

  7. Absence of NR2E1 mutations in patients with aniridia

    DEFF Research Database (Denmark)

    Corso-Díaz, Ximena; Borrie, Adrienne E; Bonaguro, Russell;

    2012-01-01

    Nuclear receptor 2E1 (NR2E1) is a transcription factor with many roles during eye development and thus may be responsible for the occurrence of certain congenital eye disorders in humans. To test this hypothesis, we screened NR2E1 for candidate mutations in patients with aniridia and other congen...

  8. Folding of viral envelope glycoproteins in the endoplasmic reticulum

    NARCIS (Netherlands)

    Braakman, L.J.; Anken, E. van

    2000-01-01

    Viral glycoproteins fold and oligomerize in the endoplasmic reticulum of the host cell. They employ the cellular machinery and receive assistance from cellular folding factors. During the folding process, they are retained in the compartment and their structural quality is checked by the quality con

  9. Spinosad is a potent inhibitor of canine P-glycoprotein

    NARCIS (Netherlands)

    Schrickx, Johannes A

    2014-01-01

    Inhibition of the drug transporter P-glycoprotein (P-gp) by the oral flea preventative spinosad has been suggested as the underlying cause of the drug-drug interaction with ivermectin. In this study, an in vitro model consisting of canine cells was validated to describe the inhibitory effect of drug

  10. beta(2)-Glycoprotein I : evolution, structure and function

    NARCIS (Netherlands)

    de Groot, P. G.; Meijers, J. C. M.

    2011-01-01

    beta(2)-Glycoprotein I (beta(2)-GPI) is a protein that circulates in blood at high concentrations. The function of beta(2)-GPI has long been an enigma. More than 20 years ago, it was discovered that beta(2)-GPI is the major antigen for the circulating antibodies in the antiphospholipid syndrome. How

  11. Glycoprotein expression by adenomatous polyps of the colon

    Science.gov (United States)

    Roney, Celeste A.; Xie, Jianwu; Xu, Biying; Jabour, Paul; Griffiths, Gary; Summers, Ronald M.

    2008-03-01

    Colon cancer is the second leading cause of cancer related deaths in the United States. Specificity in diagnostic imaging for detecting colorectal adenomas, which have a propensity towards malignancy, is desired. Adenomatous polyp specimens of the colon were obtained from the mouse model of colorectal cancer called adenomatous polyposis coli-multiple intestinal neoplasia (APC Min). Histological evaluation, by the legume protein Ulex europaeus agglutinin I (UEA-1), determined expression of the glycoprotein α-L-fucose. FITC-labelled UEA-1 confirmed overexpression of the glycoprotein by the polyps on fluorescence microscopy in 17/17 cases, of which 13/17 included paraffin-fixed mouse polyp specimens. In addition, FITC-UEA-1 ex vivo multispectral optical imaging of 4/17 colonic specimens displayed over-expression of the glycoprotein by the polyps, as compared to non-neoplastic mucosa. Here, we report the surface expression of α-L-fucosyl terminal residues by neoplastic mucosal cells of APC specimens of the mouse. Glycoprotein expression was validated by the carbohydrate binding protein UEA-1. Future applications of this method are the development of agents used to diagnose cancers by biomedical imaging modalities, including computed tomographic colonography (CTC). UEA-1 targeting to colonic adenomas may provide a new avenue for the diagnosis of colorectal carcinoma by CT imaging.

  12. Glycoprotein Ibalpha signalling in platelet apoptosis and clearance

    NARCIS (Netherlands)

    van der Wal, E.

    2010-01-01

    Storage of platelets at low temperature reduces bacterial growth and might better preserve the haemostatic function of platelets than current procedures. Incubation at 0C is known to expose ?-N-acetyl-D-glucosamine-residues on glycoprotein (GP)Ibalpha inducing receptor-clustering and platelet destru

  13. Engineered CHO cells for production of diverse, homogeneous glycoproteins

    DEFF Research Database (Denmark)

    Yang, Zhang; Wang, Shengjun; Halim, Adnan;

    2015-01-01

    genes controlling N-glycosylation in CHO cells and constructed a design matrix that facilitates the generation of desired glycosylation, such as human-like alpha 2,6-linked sialic acid capping. This engineering approach will aid the production of glycoproteins with improved properties and therapeutic...

  14. Glycoprotein Ibα clustering in platelet storage and function

    NARCIS (Netherlands)

    Gitz, E.

    2013-01-01

    Platelets are anucleated, discoid-shaped cells that play an essential role in the formation of a hemostatic plug to prevent blood loss from injured vessels. Initial platelet arrest at the damaged arterial vessel wall is mediated through the interaction between the platelet receptor glycoprotein (GP)

  15. Magnetic enzyme reactors for isolation and study of heterogeneous glycoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Korecka, Lucie [Department of Analytical Chemistry, University of Pardubice, Namesti Cs. Legii 565, 532 10 Pardubice (Czech Republic)]. E-mail: lucie.korecka@upce.cz; Jezova, Jana [Department of Analytical Chemistry, University of Pardubice, Namesti Cs. Legii 565, 532 10 Pardubice (Czech Republic); Bilkova, Zuzana [Department of Biological and Biochemical Sciences, University of Pardubice, Namesti Cs. Legii 565, 532 10 Pardubice (Czech Republic); Benes, Milan [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovskeho Namesti 2, 162 06 Prague (Czech Republic); Horak, Daniel [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovskeho Namesti 2, 162 06 Prague (Czech Republic); Hradcova, Olga [Department of Biological and Biochemical Sciences, University of Pardubice, Namesti Cs. Legii 565, 532 10 Pardubice (Czech Republic); Slovakova, Marcela [Department of Biological and Biochemical Sciences, University of Pardubice, Namesti Cs. Legii 565, 532 10 Pardubice (Czech Republic); Laboratoire Physicochimie Curie, UMR 168 CNRS/Institute Curie, Paris Cedex 05 (France); Viovy, Jean-Louis [Laboratoire Physicochimie Curie, UMR 168 CNRS/Institute Curie, Paris Cedex 05 (France)

    2005-05-15

    The newly developed magnetic micro- and nanoparticles with defined hydrophobicity and porosity were used for the preparation of magnetic enzyme reactors. Magnetic particles with immobilized proteolytic enzymes trypsin, chymotrypsin and papain and with enzyme neuraminidase were used to study the structure of heterogeneous glycoproteins. Factors such as the type of carrier, immobilization procedure, operational and storage stability, and experimental conditions were optimized.

  16. Glycoprotein Ibα clustering in platelet storage and function

    NARCIS (Netherlands)

    Gitz, E.

    2013-01-01

    Platelets are anucleated, discoid-shaped cells that play an essential role in the formation of a hemostatic plug to prevent blood loss from injured vessels. Initial platelet arrest at the damaged arterial vessel wall is mediated through the interaction between the platelet receptor glycoprotein (GP)

  17. [Obtaining monoclonal antibodies against outer membrane glycoproteins of Entamoeba histolytica].

    Science.gov (United States)

    Agundis, C; Isibasi, A; Ortíz, V; Reyes, J L; Paniagua, J; Ramírez, A; Kumate, J

    1990-01-01

    The goal of this paper was the production of monoclonal antibodies capable of detecting relevant antigens from the surface of Entamoeba histolytica trophozoites, with the purpose of using them as a diagnostic test. The cellular fusion for obtaining the monoclonal antibodies (mAb) was done with spleen cells from BALB/c mice, previously immunized with glycoproteins from the membrane, as well as Sp2/0 cells. The hybridoma supernatants were tested with ELISA, using glycoproteins and lipopeptide phosphoglycans (LPPG) as antigens. Seven hybridomas producing mAb against the glycoproteins were found. Among these, three recognize LPPG. The ability of reacting with the mAb against two molecules disappeared for all the LPPG positive ones when were treated with meta-periodate, and only three reacted against the glycoproteins. All of the mAb were of the Ig M isotypes. They were characterized by Dot blot and Western blot assays. From the results, one may deduce that some mAb recognize as epitopes the polysaccharide portion, and thus infer that they are directed of against the surface and therefore, in the future, could be used with a diagnostic purpose.

  18. The HIV-1 envelope glycoproteins: folding, function and vaccin design

    NARCIS (Netherlands)

    Sanders, Rogier W.

    2003-01-01

    The need for a vaccine against HIV is obvious, but the development of an effective vaccine has met with frustrations. The HIV envelope glycoproteins, residing in the viral membrane, are the sole viral proteins exposed on the outside of virus particles and are therefore major targets for vaccine

  19. Cancer Biomarker Discovery: Lectin-Based Strategies Targeting Glycoproteins

    Directory of Open Access Journals (Sweden)

    David Clark

    2012-01-01

    Full Text Available Biomarker discovery can identify molecular markers in various cancers that can be used for detection, screening, diagnosis, and monitoring of disease progression. Lectin-affinity is a technique that can be used for the enrichment of glycoproteins from a complex sample, facilitating the discovery of novel cancer biomarkers associated with a disease state.

  20. CYP2A6 and CYP2E1 polymorphisms in a Brazilian population living in Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    A. Rossini

    2006-02-01

    Full Text Available Cytochrome P450 (CYP is a superfamily of enzymes involved in the metabolism of endogenous compounds and xenobiotics. CYP2A6 catalyzes the oxidation of nicotine and the activation of carcinogens such as aflatoxin B1 and nitrosamines. CYP2E1 metabolizes ethanol and other low-molecular weight compounds and can also activate nitrosamines. The CYP2A6 and CYP2E1 genes are polymorphic, altering their catalytic activities and susceptibility to cancer and other diseases. A number of polymorphisms described are ethnic-dependent. In the present study, we determined the genotype and allele frequencies of the main CYP2A6 and CYP2E1 polymorphisms in a group of 289 volunteers recruited at the Central Laboratory of Hospital Universitário Pedro Ernesto. They had been residing in the city of Rio de Janeiro for at least 6 months and were divided into two groups according to skin color (white and non-white. The alleles were determined by allele specific PCR (CYP2A6 or by PCR-RFLP (CYP2E1. The frequencies of the CYP2A6*1B and CYP2A6*2 alleles were 0.29 and 0.02 for white individuals and 0.24 and 0.01 for non-white individuals, respectively. The CYP2A6*5 allele was not found in the population studied. Regarding the CYP2E1*5B allele, we found a frequency of 0.07 in white individuals, which was statistically different (P < 0.05 from that present in non-white individuals (0.03. CYP2E1*6 allele frequency was the same (0.08 in both groups. The frequencies of CYP2A6*1B, CYP2A6*2 and CYP2E1*6 alleles in Brazilians are similar to those found in Caucasians and African-Americans, but the frequency of the CYP2E1*5B allele is higher in Brazilians.

  1. CYP2A6 and CYP2E1 polymorphisms in a Brazilian population living in Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Rossini A.

    2006-01-01

    Full Text Available Cytochrome P450 (CYP is a superfamily of enzymes involved in the metabolism of endogenous compounds and xenobiotics. CYP2A6 catalyzes the oxidation of nicotine and the activation of carcinogens such as aflatoxin B1 and nitrosamines. CYP2E1 metabolizes ethanol and other low-molecular weight compounds and can also activate nitrosamines. The CYP2A6 and CYP2E1 genes are polymorphic, altering their catalytic activities and susceptibility to cancer and other diseases. A number of polymorphisms described are ethnic-dependent. In the present study, we determined the genotype and allele frequencies of the main CYP2A6 and CYP2E1 polymorphisms in a group of 289 volunteers recruited at the Central Laboratory of Hospital Universitário Pedro Ernesto. They had been residing in the city of Rio de Janeiro for at least 6 months and were divided into two groups according to skin color (white and non-white. The alleles were determined by allele specific PCR (CYP2A6 or by PCR-RFLP (CYP2E1. The frequencies of the CYP2A6*1B and CYP2A6*2 alleles were 0.29 and 0.02 for white individuals and 0.24 and 0.01 for non-white individuals, respectively. The CYP2A6*5 allele was not found in the population studied. Regarding the CYP2E1*5B allele, we found a frequency of 0.07 in white individuals, which was statistically different (P < 0.05 from that present in non-white individuals (0.03. CYP2E1*6 allele frequency was the same (0.08 in both groups. The frequencies of CYP2A6*1B, CYP2A6*2 and CYP2E1*6 alleles in Brazilians are similar to those found in Caucasians and African-Americans, but the frequency of the CYP2E1*5B allele is higher in Brazilians.

  2. Preclinical safety assessment of Ad[I/PPT-E1A], a novel oncolytic adenovirus for prostate cancer.

    Science.gov (United States)

    Schenk, Ellen; Essand, Magnus; Kraaij, Robert; Adamson, Rachel; Maitland, Norman J; Bangma, Chris H

    2014-03-01

    Prostate cancer is the most common malignancy in the Western world. Patients can be cured only when the tumor has not metastasized outside the prostate. However, treatment with curative intent fails in a significant number of men, often resulting in untreatable progressive disease with a fatal outcome. Oncolytic adenovirus therapy may be a promising adjuvant treatment to reduce local failure or the outgrowth of micrometastatic disease. Within the European gene therapy consortium GIANT, we have developed a novel prostate-specific oncolytic adenovirus: Ad[I/PPT-E1A]. This adenovirus specifically kills prostate cells via prostate-specific replication. This article describes the clinical development of Ad[I/PPT-E1A] with particular reference to the preclinical safety assessment of this novel virus. The preclinical safety assessment involved an efficacy study in a human orthotopic xenograft mouse model, a specificity study in human primary cells, and a toxicity study in normal mice. These studies confirmed that Ad[I/PPT-E1A] efficiently kills prostate tumor cells in vivo, is not harmful to other organs, and is well tolerated in mice after systemic delivery. The safety, as well as the immunological effects of Ad[I/PPT-E1A] as a local adjuvant therapy, will now be studied in a phase I dose-escalating trial in patients with localized prostate cancer who are scheduled for curative radical prostatectomy and can be used as an updated paradigm for similar therapeutic viruses.

  3. Pre-clinical safety assessment of Ad[I/PPT-E1A], a novel oncolytic adenovirus for prostate cancer.

    Science.gov (United States)

    Schenk, Ellen; Essand, Magnus; Kraaij, Robert; Adamson, Rachel; Maitland, Norman; Bangma, Chris H

    2014-02-18

    Prostate cancer is the most common malignancy in the Western world. Patients can only be cured when the tumour has not metastasised outside the prostate. However, treatment with curative intent fails in a significant number of men, often resulting in untreatable progressive disease with a fatal outcome. Oncolytic adenovirus therapy may be a promising adjuvant treatment to reduce local failure or the outgrowth of micrometastatic disease. Within the European gene therapy consortium GIANT, we have developed a novel prostate-specific oncolytic adenovirus: Ad[I/PPT-E1A] that specifically kills prostate cells via prostate-specific replication. This paper describes the clinical development of Ad[I/PPT-E1A] with particular reference to the pre-clinical safety assessment of this novel virus. The pre-clinical safety assessment involved an efficacy study in a human orthotopic xenograft mouse model, a specificity study in human primary cells and a toxicity study in normal mice. These studies confirmed that Ad[I/PPT-E1A] efficiently kills prostate tumour cells in vivo, is not harmful to other organs and is well-tolerated in mice after systemic delivery. The safety, as well as the immunological effects of Ad[I/PPT-E1A] as a local adjuvant therapy will now be studied in a phase I dose-escalating trial in patients with localised prostate cancer who are scheduled for curative radical prostatectomy and can be used as an updated paradigm for similar therapeutic viruses.

  4. Identification and Characteristics of a Novel E1 Like Gene nUBE1L in Human Testis

    Institute of Scientific and Technical Information of China (English)

    Hui ZHU; Jia-Hao SHA; Zuo-Min ZHOU; Ran HUO; Xiao-Yan HUANG; Li LU; Min LIN; Li-Rong WANG; Ya-Dong ZHOU; Jian-Min LI

    2004-01-01

    A gene,presumably involved in spermatogenesis,was identified and characterized by using cDNA microarray.Hybridization intensity was 2.13 fold higher in adult testis than that in fetal testis.The full length of this gene was 4288 bp and it encoded a 578 amino acid protein.Conserved structure and amino acid sequence analysis revealed that the protein contained 1 Thif-domain,2 UBACT-domains,and a functional active site cysteine lay upstream of UBACT domain,all of them also existed in ubiquitinactivating enzyme E1 and E1 like proteins.So we named this gene as a novel ubiquitin-activating enzyme E1 like gene(nUBE1L).Expression profile showed that nUBEIL was predominantly expressed in testis.Comparison of the expression of nUBE1L in different developmental stages of testis indicated that it was highly expressed in adult testis.In conclusion,nUBE1L is a novel human E1 like gene highly expressed in adult testis,which plays key role in ubiquitin system,and accordingly influences spermatogenesis and male fertility.

  5. Infection with E1B-mutant adenovirus stabilizes p53 but blocks p53 acetylation and activity through E1A

    DEFF Research Database (Denmark)

    Savelyeva, I.; Dobbelstein, M.

    2011-01-01

    Wild-type adenovirus type 5 eliminates p53 through the E1B-55 kDa and E4-34 kDa gene products. Deletion or mutation of E1B-55 kDa has long been thought to confer p53-selective replication of oncolytic viruses. We show here that infection with E1B-defective adenovirus mutants induces massive...... accumulation of p53, without obvious defects in p53 localization, phosphorylation, conformation and oligomerization. Nonetheless, p53 completely failed to induce its target genes in this scenario, for example, p21/CDKN1A, Mdm2 and PUMA. Two regions of the E1A gene products independently contributed...... acetylation in infected cells. Mutating either of these E1A regions, in addition to E1B, partially restored p21 mRNA levels. Our findings argue that adenovirus attenuates p53-mediated p21 induction, through at least two E1B-independent mechanisms. Other virus species and cancer cells may employ analogous...

  6. Tmed2 accelerates murine MC3T3-E1 pre-osteoblast proliferation in vitro%Tmed2促进体外小鼠前成骨细胞MC3T3-E1增殖

    Institute of Scientific and Technical Information of China (English)

    熊元; 熊霞辉; 卢雅彬; 朱宁; 陈梅红

    2012-01-01

    目的 研究Tmed2基因对小鼠前成骨细胞增殖的影响.方法1)分别在小鼠MC3T3-E1细胞中过表达和抑制Tmed2,检测细胞增殖情况.2)用雌激素处理细胞后,检测细胞的增殖及Tmed2基因的表达量.荧光实时定量PCR检测mRNA水平,MTS法检测细胞活力和增殖,流式细胞术检测细胞周期,Western blot法检测蛋白水平.结果 过表达Tmed2使MC3T3 -E1细胞的增殖速度加快,细胞周期中S期细胞比例明显增加,且Cyclin A的表达升高.而抑制Tmed2基因表达使MC3T3-E1细胞的增殖速度减慢.雌激素处理使细胞增殖速度加快的同时,Tmed2基因的表达显著增高.结论 Tmed2通过上调Cyclin A的表达,使S期细胞比例增加,加快小鼠前成骨细胞MC3T3-E1的增殖.此外,Tmed2的表达受雌激素的调控,可能参与雌激素促进MC3T3-E1细胞增殖的作用.%Objective To study the role of Tmed2 in murine pre-osteoblast proliferation. Methods 1) Over-express and knock down Tmed2, and the proliferation rate of MC3T3-E1 cell was then detected. 2) MC3T3-E1 cells were treated with p-Estradiol, cell number was then counted and the mRNA level of Tmed2 was analyzed. Quantitative real-time PCR was used to measure the mRNA level, MTS assay was used to assess the cell proliferation rate, flow eytometry was used to figure out the cell cycle distribution, and the protein level was evaluated by Western blot. Results Over-expression of Tmed2 accelerated MC3T3-E1 cell proliferation, and the proportion of cells in S phase markedly increased. The expression of Cyclin A also increased. On the contrary, Knockdown of Tmed2 decelerated MC3T3-E1 cell proliferation. In β-Estradiol promoted MC3T3-E1 proliferation, the mRNA level of Tmed2 remarkably increased. Conclusions Tmed2 accelerates murine pre-osteoblast MC3T3-E1 proliferation through up-regulating Cyclin A expression and therefore increasing the proportion of cells in S phase. In addition, the expression of Tmed2 is regulated by

  7. Transcriptional repression of hDaxx enhanced by adenovirus 12 E1B 55-kDa oncoprotein interacting with hDaxx

    Institute of Scientific and Technical Information of China (English)

    万艳平; 吴移谋; 朱翠明; 尹卫国; 蔡恒玲; 余敏君

    2004-01-01

    Background Daxx has been identified as a nuclear protein that involves in apoptosis and transcriptional repression. Daxx co-localizes with the promyelocytic leukemia (PML) protein and regulates transcription. Human Daxx (hDaxx) is a protein that functions as a transcriptional regulation through its interaction with some DNA-associated proteins. The aim of this study was to explore the transcriptional regulatory effect of hDaxx interacting with adenovirus (Ad) 12 E1B (Ad12E1B) 55-kDa oncoprotein.Methods The co-localization of hDaxx-Ad12E1B or hDaxx-PML protein in the nucleus was observed under a confocal microscope. Interaction of hDaxx and Ad12E1B was analyzed by yeast two-hybrid assay. Direct binding of hDaxx and Ad12E1B was analyzed using coimmunoprecipitation and Western blot in vivo and in vitro. The activity of a luciferase reporter gene, which was regulated by an hDaxx modulated thymidine kinase (TK) promoter, was detected in an automat luminometer.Results Ad12E1B, which co-localized with hDaxx in the nuclei of G401-CC3 cells, disrupted the co-localization of hDaxx and PML in the PML oncogenic domains (PODs). hDaxx bound directly to Ad12E1B in vivo and in vitro. hDaxx interacted with Ad12E1B along its full length. Ad12E1B enhanced transcriptional repression activity of hDaxx.Conclusion Ad12E1B disrupts the co-localization of hDaxx with PML in PODs and enhances transcriptional repression activity of hDaxx.

  8. Metabolism of methyl tert-butyl ether and other gasoline ethers in mouse liver microsomes lacking cytochrome P450 2E1.

    Science.gov (United States)

    Hong, J Y; Wang, Y Y; Bondoc, F Y; Yang, C S; Gonzalez, F J; Pan, Z; Cokonis, C D; Hu, W Y; Bao, Z

    1999-03-08

    To reduce the production of pollutants in motor vehicle exhaust, methyl tert-butyl ether (MTBE) and other ethers such as ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME) are added to gasoline as oxygenates for more complete combustion. Metabolism of these gasoline ethers is catalyzed by cytochrome P450 (P450) enzymes. P450 2E1, which metabolizes diethyl ether, was suggested to be an enzyme involved. The present study used 2E1 knock-out mice (2E1-/-) to assess the contribution of 2E1 to the metabolism of MTBE, ETBE and TAME. Liver microsomes prepared from the 2E1 knock-out mice lacked 2E1 activity (assayed as N-nitrosodimethylamine demethylation), but were still active in metabolizing all three gasoline ethers. The levels of ether-metabolizing activity (nmol/min per mg) in the liver microsomes from 7 week old female 2E1 knock-out mice were 0.54+/-0.17 for MTBE, 0.51+/-0.24 for ETBE and 1.14+/-0.25 for TAME at a 1 mM substrate concentration. These activity levels were not significantly different from those of the sex- and age-matched C57BL/6N and 129/Sv mice, which are the parental lineage strains of the 2E1 knock-out mice and are both 2E1+/+. Our results clearly demonstrate that 2E1 plays a negligible role in the metabolism of MTBE, ETBE and TAME in mouse livers.

  9. Lectin-based glycoproteomics to explore and analyze hepatocellular carcinoma-related glycoprotein markers.

    Science.gov (United States)

    Dai, Zhi; Zhou, Jian; Qiu, Shuang-Jian; Liu, Yin-Kun; Fan, Jia

    2009-09-01

    More and more new diagnostic biomarkers of hepatocellular carcinoma (HCC) have been found in association with advances in the standardization of 2-DE coupled with MS analysis. However, the diagnosis of HCC is still detected in the late stages of the disease, when treatment options are limited and prognosis is poor. The glycosylation of proteins is known to change in tumor cells during the development of HCC as the result of alterations in the levels of glycosyltransferases, such as increased fucosylation of Golgi Protein 73 and alpha-fetoprotein. These structural changes can influence the function or physiochemical properties of a protein, resulting in abnormal cancer cell behavior. Therefore, identification of HCC-related glycoprotein markers and analysis of glycan structural alterations might assist in the early detection of HCC. Here, we summarize lectin-based glycoproteomic strategies for the discovery of relevant biomarkers of HCC. The carbohydrate-binding specificities of different lectins offer a biological affinity approach that complements existing MS capabilities. These strategies involve the enrichment of glycoproteins or glycopeptides by lectins, followed by releasing carbohydrates with peptide-N-glycosidase F or reductive beta-elimination. The obtained glycopeptides are then identified by automated MS/MS and structural analysis of glycans is performed through modern methods such as quadrupole IT-TOF, MALDI-TOF/TOF and lectin microarray. These strategies will lead to faster and more clinically adaptable tests with greater sensitivity and specificity.

  10. Trophoblast glycoprotein promotes pancreatic ductal adenocarcinoma cell metastasis through Wnt/planar cell polarity signaling.

    Science.gov (United States)

    He, Ping; Jiang, Shuheng; Ma, Mingze; Wang, Yang; Li, Rongkun; Fang, Fang; Tian, Guangang; Zhang, Zhigang

    2015-07-01

    Trophoblast glycoprotein (TPBG), a 72 kDa glycoprotein was identified using a monoclonal antibody, which specifically binds human trophoblast. The expression of TPBG in normal tissues is limited; however, it is upregulated in numerous types of cancer. When TPBG is expressed at a high level, this usually indicates a poor clinical outcome. In the present study, it was demonstrated that TPBG was more commonly observed in human pancreatic ductal adenocarcinoma (PDAC) compared with normal pancreatic tissue. Immunohistochemical analysis of PDAC tissue microarrays indicated that the expression of TPBG in PDAC tissues was closely correlated with the tumor-node-metastasis stage of the tumor. Silencing of TPBG in PDAC cell lines resulted in a decreased ability of cancer cell migration and invasion. Further investigation demonstrated that the Wnt/planar cell polarity signaling pathway was suppressed, as the expression of Wnt5a and the activation of c-Jun N-terminal kinase was inhibited following TPBG knockdown. In conclusion, the present study provided evidence that TPBG is involved in PDAC metastasis, and that TPBG and its associated signaling pathways may be a suitable target for PDAC therapy.

  11. Sequence and functional analysis of the envelope glycoproteins of hepatitis C virus variants selectively transmitted to a new host.

    Science.gov (United States)

    D'Arienzo, Valentina; Moreau, Alain; D'Alteroche, Louis; Gissot, Valérie; Blanchard, Emmanuelle; Gaudy-Graffin, Catherine; Roch, Emmanuelle; Dubois, Frédéric; Giraudeau, Bruno; Plantier, Jean-Christophe; Goudeau, Alain; Roingeard, Philippe; Brand, Denys

    2013-12-01

    Hepatitis C virus (HCV) remains a challenging public health problem worldwide. The identification of viral variants establishing de novo infections and definition of the phenotypic requirements for transmission would facilitate the design of preventive strategies. We explored the transmission of HCV variants in three cases of acute hepatitis following needlestick accidents. We used single-genome amplification of glycoprotein E1E2 gene sequences to map the genetic bottleneck upon transmission accurately. We found that infection was likely established by a single variant in two cases and six variants in the third case. Studies of donor samples showed that the transmitted variant E1E2 amino acid sequences were identical or closely related to those of variants from the donor virus populations. The transmitted variants harbored a common signature site at position 394, within hypervariable region 1 of E2, together with additional signature amino acids specific to each transmission pair. Surprisingly, these E1E2 variants conferred no greater capacity for entry than the E1E2 derived from nontransmitted variants in lentiviral pseudoparticle assays. Mutants escaping the antibodies of donor sera did not predominate among the transmitted variants either. The fitness parameters affecting the selective outgrowth of HCV variants after transmission in an immunocompetent host may thus be more complex than those suggested by mouse models. Human antibodies directed against HCV envelope effectively cross-neutralized the lentiviral particles bearing E1E2 derived from transmitted variants. These findings provide insight into the molecular mechanisms underlying HCV transmission and suggest that viral entry is a potential target for the prevention of HCV infection.

  12. Putative functions of extracellular matrix glycoproteins in secondary palate morphogenesis

    Science.gov (United States)

    d'Amaro, Rocca; Scheidegger, Rolf; Blumer, Susan; Pazera, Pawel; Katsaros, Christos; Graf, Daniel; Chiquet, Matthias

    2012-01-01

    Cleft palate is a common birth defect in humans. Elevation and fusion of paired palatal shelves are coordinated by growth and transcription factors, and mutations in these can cause malformations. Among the effector genes for growth factor signaling are extracellular matrix (ECM) glycoproteins. These provide substrates for cell adhesion (e.g., fibronectin, tenascins), but also regulate growth factor availability (e.g., fibrillins). Cleft palate in Bmp7 null mouse embryos is caused by a delay in palatal shelf elevation. In contrast, palatal shelves of Tgf-β3 knockout mice elevate normally, but a cleft develops due to their failure to fuse. However, nothing is known about a possible functional interaction between specific ECM proteins and Tgf-β/Bmp family members in palatogenesis. To start addressing this question, we studied the mRNA and protein distribution of relevant ECM components during secondary palate development, and compared it to growth factor expression in wildtypewild type and mutant mice. We found that fibrillin-2 (but not fibrillin-1) mRNA appeared in the mesenchyme of elevated palatal shelves adjacent to the midline epithelial cells, which were positive for Tgf-β3 mRNA. Moreover, midline epithelial cells started expressing fibronectin upon contact of the two palatal shelves. These findings support the hypothesis that fibrillin-2 and fibronectin are involved in regulating the activity of Tgf-β3 at the fusing midline. In addition, we observed that tenascin-W (but not tenascin-C) was misexpressed in palatal shelves of Bmp7-deficient mouse embryos. In contrast to tenascin-C, tenascin-W secretion was strongly induced by Bmp7 in embryonic cranial fibroblasts in vitro. These results are consistent with a putative function for tenascin-W as a target of Bmp7 signaling during palate elevation. Our results indicate that distinct ECM proteins are important for morphogenesis of the secondary palate, both as downstream effectors and as regulators of Tgf

  13. Participation of the 39-kDa glycoprotein (gp39) of the vitelline envelope of Bufo arenarum eggs in sperm-egg interaction.

    Science.gov (United States)

    Barrera, Daniel; Llanos, Ricardo J; Miceli, Dora C

    2012-05-01

    The acquisition of egg fertilizability in Bufo arenarum takes place during the oviductal transit and during this process the extracellular coelomic envelope (CE) of the eggs is converted into the vitelline envelope (VE). It has been stated that one of the necessary events leading to a fertilizable state is the proteolytic cleavage of CE glycoproteins in the oviductal pars recta by oviductin, a serine protease. Consequently, there is a marked increase in the relative quantity of glycoproteins with 39 (gp39) and 42 kDa (gp42) in the VE. In the present study, sperm-VE binding assays using heat-solubilized biotin-conjugated VE glycoproteins revealed that both gp39 and gp42 have sperm binding capacity. According to this result, our study was focused on gp39, a glycoprotein that we have previously reported as a homologue of mammalian ZPC. For this purpose, rabbit polyclonal antibodies against gp39 were generated at our laboratory. The specificity of the antibodies was confirmed with western blot of VE glycoproteins separated on SDS-PAGE. Immunohistochemical and immunoelectron studies showed gp39 distributed throughout the width of the VE. In addition, immunofluorescence assays probed that gp39 bound to the sperm head. Finally, as an approach to elucidate the possible involvement of gp39 in fertilization, inhibition assays showed that pretreatment of eggs with antibodies against gp39 generated a significant decrease in the fertilization rate. Therefore, our findings suggest that gp39, which is modified by oviductal action, participates as a VE glycoprotein ligand for sperm in Bufo arenarum fertilization.

  14. Identification of porcine alveolar macrophage glycoproteins involved in infection of porcine respiratory and reproductive syndrome virus.

    NARCIS (Netherlands)

    Wissink, E.H.J.; Wijk, van H.A.R.; Pol, J.M.A.; Godeke, G.J.; Rijn, van P.A.; Rottier, P.J.M.; Meulenberg, J.J.M.

    2003-01-01

    The aim of this study was to identify the receptor(s) for PRRSV on porcine alveolar macrophages (PAMs) by producing monoclonal antibodies (MAbs) against these cells. Hybridoma supernatants were selected for their ability to block PRRSV infection. Four MAbs, 1-8D2, 9.4C7, 9.9F2, and 3-3H2 inhibited i

  15. Structural Basis for Cooperative Binding of Azoles to CYP2E1 as Interpreted through Guided Molecular Dynamics Simulations

    Science.gov (United States)

    Levy, Joseph W.; Hartman, Jessica H.; Perry, Martin D.; Miller, Grover P.

    2015-01-01

    CYP2E1 metabolizes a wide array of small, hydrophobic molecules, resulting in their detoxification or activation into carcinogens through Michaelis-Menten as well as cooperative mechanisms. Nevertheless, the molecular determinants for CYP2E1 specificity and metabolic efficiency toward these compounds are still unknown. Herein, we employed computational docking studies coupled to Molecular Dynamics simulations to provide a critical perspective for understanding a structural basis for cooperativity observed for an array of azoles from our previous binding and catalytic studies (Hartman, JH et al (2014) Biochem Pharmacol 87, 523-33). The resulting 28 CYP2E1 complexes in this study revealed a common passageway for azoles that included a hydrophobic steric barrier causing a pause in movement toward the active site. The entrance to the active site acted like a second sieve to restrict access to the inner chamber. Collectively, these interactions impacted the final orientation of azoles reaching the active site and hence could explain differences in their biochemical properties observed in our previous studies, such as the consequences of methylation at position 5 of the azole ring. The association of a second azole demonstrated significant differences in interactions stabilizing the bound complex than observed for the first binding event. Intermolecular interactions occurred between the two azoles as well as CYP2E1 residue side chains and backbone and involved both hydrophobic contacts and hydrogen bonds. The relative importance of these interactions depended on the structure of the respective azoles indicating the absence of specific defining criteria for binding unlike the well-characterized dominant role of hydrophobicity in active site binding. Consequently, the structure activity relationships described here and elsewhere are necessary to more accurately identify factors impacting the observation and significance of cooperativity in CYP2E1 binding and catalysis

  16. Role of CYP2E1-mediated metabolism in the acute and vestibular toxicities of nineteen nitriles in the mouse.

    Science.gov (United States)

    Saldaña-Ruíz, Sandra; Soler-Martín, Carla; Llorens, Jordi

    2012-01-25

    Allylnitrile, cis-crotononitrile, and 3,3'-iminodipropionitrile are known to cause vestibular toxicity in rodents, and evidence is available indicating that cis-2-pentenenitrile shares this effect. We evaluated nineteen nitriles for vestibular toxicity in wild type (129S1) and CYP2E1-null mice, including all the above, several neurotoxic nitriles, and structurally similar nitriles. A new acute toxicity test protocol was developed to facilitate evaluation of the vestibular toxicity by a specific behavioral test battery at doses up to sub-lethal levels while using a limited number of animals. A mean number of 8.5±0.3 animals per nitrile, strain and sex was necessary to obtain evidence of vestibular toxicity and optionally an estimation of the lethal dose. For several but not all nitriles, lethal doses significantly increased in CYP2E1-null mice. The protocol revealed the vestibular toxicity of five nitriles, including previously identified ototoxic compounds and one nitrile (trans-crotononitrile) known to have a different profile of neurotoxic effects in the rat. In all five cases, both sexes were affected and no decrease in susceptibility was apparent in CYP2E1-null mice respect to 129S1 mice. Fourteen nitriles caused no vestibular toxicity, including six nitriles tested in CYP2E1-null mice at doses significantly larger than the maximal doses that can be tested in wild type animals. We conclude that only a subset of low molecular weight nitriles is toxic to the vestibular system, that species-dependent differences exist in this vestibular toxicity, and that CYP2E1-mediated metabolism is not involved in this effect of nitriles although it has a role in the acute lethality of some of these compounds. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  17. Genetic Diversity Underlying the Envelope Glycoproteins of Hepatitis C Virus: Structural and Functional Consequences and the Implications for Vaccine Design

    Directory of Open Access Journals (Sweden)

    Alexander W. Tarr

    2015-07-01

    Full Text Available In the 26 years since the discovery of Hepatitis C virus (HCV a major global research effort has illuminated many aspects of the viral life cycle, facilitating the development of targeted antivirals. Recently, effective direct-acting antiviral (DAA regimens with >90% cure rates have become available for treatment of chronic HCV infection in developed nations, representing a significant advance towards global eradication. However, the high cost of these treatments results in highly restricted access in developing nations, where the disease burden is greatest. Additionally, the largely asymptomatic nature of infection facilitates continued transmission in at risk groups and resource constrained settings due to limited surveillance. Consequently a prophylactic vaccine is much needed. The HCV envelope glycoproteins E1 and E2 are located on the surface of viral lipid envelope, facilitate viral entry and are the targets for host immunity, in addition to other functions. Unfortunately, the extreme global genetic and antigenic diversity exhibited by the HCV glycoproteins represents a significant obstacle to vaccine development. Here we review current knowledge of HCV envelope protein structure, integrating knowledge of genetic, antigenic and functional diversity to inform rational immunogen design.

  18. Fluorescent Protein-Tagged Sindbis Virus E2 Glycoprotein Allows Single Particle Analysis of Virus Budding from Live Cells.

    Science.gov (United States)

    Jose, Joyce; Tang, Jinghua; Taylor, Aaron B; Baker, Timothy S; Kuhn, Richard J

    2015-12-01

    Sindbis virus (SINV) is an enveloped, mosquito-borne alphavirus. Here we generated and characterized a fluorescent protein-tagged (FP-tagged) SINV and found that the presence of the FP-tag (mCherry) affected glycoprotein transport to the plasma membrane whereas the specific infectivity of the virus was not affected. We examined the virions by transmission electron cryo-microscopy and determined the arrangement of the FP-tag on the surface of the virion. The fluorescent proteins are arranged icosahedrally on the virus surface in a stable manner that did not adversely affect receptor binding or fusion functions of E2 and E1, respectively. The delay in surface expression of the viral glycoproteins, as demonstrated by flow cytometry analysis, contributed to a 10-fold reduction in mCherry-E2 virus titer. There is a 1:1 ratio of mCherry to E2 incorporated into the virion, which leads to a strong fluorescence signal and thus facilitates single-particle tracking experiments. We used the FP-tagged virus for high-resolution live-cell imaging to study the spatial and temporal aspects of alphavirus assembly and budding from mammalian cells. These processes were further analyzed by thin section microscopy. The results demonstrate that SINV buds from the plasma membrane of infected cells and is dispersed into the surrounding media or spread to neighboring cells facilitated by its close association with filopodial extensions.

  19. Fluorescent Protein-Tagged Sindbis Virus E2 Glycoprotein Allows Single Particle Analysis of Virus Budding from Live Cells

    Directory of Open Access Journals (Sweden)

    Joyce Jose

    2015-11-01

    Full Text Available Sindbis virus (SINV is an enveloped, mosquito-borne alphavirus. Here we generated and characterized a fluorescent protein-tagged (FP-tagged SINV and found that the presence of the FP-tag (mCherry affected glycoprotein transport to the plasma membrane whereas the specific infectivity of the virus was not affected. We examined the virions by transmission electron cryo-microscopy and determined the arrangement of the FP-tag on the surface of the virion. The fluorescent proteins are arranged icosahedrally on the virus surface in a stable manner that did not adversely affect receptor binding or fusion functions of E2 and E1, respectively. The delay in surface expression of the viral glycoproteins, as demonstrated by flow cytometry analysis, contributed to a 10-fold reduction in mCherry-E2 virus titer. There is a 1:1 ratio of mCherry to E2 incorporated into the virion, which leads to a strong fluorescence signal and thus facilitates single-particle tracking experiments. We used the FP-tagged virus for high-resolution live-cell imaging to study the spatial and temporal aspects of alphavirus assembly and budding from mammalian cells. These processes were further analyzed by thin section microscopy. The results demonstrate that SINV buds from the plasma membrane of infected cells and is dispersed into the surrounding media or spread to neighboring cells facilitated by its close association with filopodial extensions.

  20. Antibody to E1 peptide of hepatitis C virus genotype 4 inhibits virus binding and entry to HepG2 cells in vitro

    Science.gov (United States)

    EL-Awady, Mostafa K; Tabll, Ashraf A; Atef, Khaled; Yousef, Samar S; Omran, Moataza H; El-Abd, Yasmin; Bader-Eldin, Noha G; Salem, Ahmad M; Zohny, Samir F; El-Garf, Wael T

    2006-01-01

    AIM: To analyze the neutralizing activity of antibodies against E1 region of hepatitis C virus (HCV). Specific polyclonal antibody was raised via immunization of New Zealand rabbits with a synthetic peptide that had been derived from the E1 region of HCV and was shown to be highly conserved among HCV published genotypes. METHODS: Hyper-immune HCV E1 antibodies were incubated over night at 4 °C with serum samples positive for HCV RNA, with viral loads ranging from 615 to 3.2 million IU/ mL. Treated sera were incubated with HepG2 cells for 90 min. Blocking of viral binding and entry into cells by anti E1 antibody were tested by means of RT-PCR and flow cytometry. RESULTS: Direct immunostaining using FITC conjugated E1 antibody followed by Flow cytometric analysis showed reduced mean fluorescence intensity in samples pre-incubated with E1 antibody compared with untreated samples. Furthermore, 13 out of 18 positive sera (72%) showed complete inhibition of infectivity as detected by RT-PCR. CONCLUSION: In house produced E1 antibody, blocks binding and entry of HCV virion infection to target cells suggesting the involvement of this epitope in virus binding and entry. Isolation of these antibodies that block virus attachment to human cells are useful as therapeutic reagents. PMID:16688798

  1. Antibody to E1 peptide of hepatitis C virus genotype 4 inhibits virus binding and entry to HepG2 cells in vitro

    Institute of Scientific and Technical Information of China (English)

    Mostafa K EL-Awady; Wael T El-Garf; Ashraf A Tabll; Khaled Atef; Samar S Yousef; Moataza H Omran; Yasmin El-Abd; Noha G Bader-Eldin; Ahmad M Salem; Samir F Zohny

    2006-01-01

    AIM: To analyze the neutralizing activity of antibodies against E1 region of hepatitis C virus (HCV). Specific polyclonal antibody was raised via immunization of New Zealand rabbits with a synthetic peptide that had been derived from the E1 region of HCV and was shown to be highly conserved among HCV published genotypes.METHODS: Hyper-immune HCV E1 antibodies were incubatecd over night at 4 ℃ with serum samples positive for HCV RNA, with viral loads ranging from 615 to 3.2 million IU/mL. Treated sera were incubated with HepG2 cells for 90 min. Blocking of viral binding and entry into cells by anti E1 antibody were tested by means of RTPCR and flow cytometry.RESULTS: Direct immunostaining using FTTC conjugated E1 antibody followed by Flow cytometric analysis showed reduced mean fluorescence intensity in samples pre-incubated with E1 antibody compared with untreated samples. Furthermore, 13 out of 18 positive sera (72%)showed complete inhibition of infectivity as detected by RT-PCR.CONCLUSION: In house produced E1 antibody, blocks binding and entry of HCV virion infection to target cells suggesting the involvement of this epitope in virus binding and entry. Isolation of these antibodies that block virus attachment to human cells are useful as therapeutic reagents.

  2. Biosynthesis of ascites sialoglycoprotein-1, the major O-linked glycoprotein of 13762 rat mammary adenocarcinoma ascites cells

    Energy Technology Data Exchange (ETDEWEB)

    Spielman, J.

    1987-01-01

    The present studies were undertaken to determine the timing of the major events in biosynthesis, and to characterize the contributions of chain initiation and elongation in maturation of the glycoprotein. Initiation of the earliest O-linked chains was detected by analysis of conversion of {sup 3}H-thr to {sup 3}H 2-aminobutyrate following mild alkaline borohydride elimination of O-linked sugars from peanut lectin-precipitated ASGP-1. Initiation was detected within 5 min of translation; amino sugar analysis of GlcNH{sub 2}-labeled, trypsinized cells also showed that GalNAc was added as late as 5 min prior to arrival of ASGP-1 at the cell surface. Thus initiation occurs throughout biosynthesis. Maturation of the glycoprotein from a lightly-glycosylated immature form to the heavily-glycosylated mature from involved both continued initiation of new chains and chain elongation, and occurred with a half-time of about 30 min. Analysis of labeled ASGP-1 released from the cell surface by trypsinization showed that although some newly-synthesized ASGP-1 reached the cell surface within 70-80 min of protein synthesis, the half-time for appearance of mature glycoprotein was in excess of 4 hr, indicating that most molecules reside in an intracellular compartment(s) for a considerable time.

  3. Improved Plant-based Production of E1 endoglucanase Using Potato: Expression Optimization and Tissue Targeting

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Ziyu [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hooker, Brian S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Anderson, Daniel B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thomas, Steven R. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2000-06-01

    Optimization of Acidothermus cellulolyticus endoglucanase (E1) gene expression in transgenic potato (Solanum tuberosum L.) was examined in this study, where the E1 coding sequence was transcribed under control of a leaf specific promoter (tomato RbcS-3C) or the Mac promoter (a hybrid promoter of mannopine synthase promoter and cauliflower mosaic virus 35S promoter enhancer region). Average E1 activity in leaf extracts of potato transformants, in which E1 protein was targeted by a chloroplast signal peptide and an apoplast signal peptide were much higher than those by an E1 native signal peptide and a vacuole signal peptide. E1 protein accumulated up to 2.6% of total leaf soluble protein, where E1 gene was under control of the RbcS-3C promoter, alfalfa mosaic virus 5-untranslated leader, and RbcS-2A signal peptide. E1 protein production, based on average E1 activity and E1 protein accumulation in leaf extracts, is higher in potato than those measured previously in transgenic tobacco bearing the same transgene constructs. Comparisons of E1 activity, protein accumulation, and relative mRNA levels showed that E1 expression under control of tomato RbcS-3C promoter was specifically localized in leaf tissues, while E1 gene was expressed in both leaf and tuber tissues under control of Mac promoter. This suggests dual-crop applications in which potato vines serve as enzyme production `bioreactors' while tubers are preserved for culinary applications.

  4. Ghrelin inhibits the apoptosis of MC3T3-E1 cells through ERK and AKT signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Qiu-Hua; Liu, Yuan; Wu, Shan-Shan; Cui, Rong-Rong; Yuan, Ling-Qing, E-mail: allenylq@hotmail.com; Liao, Er-Yuan, E-mail: eyliao@21cn.com

    2013-11-01

    Ghrelin is a 28-amino-acid peptide that acts as a natural endogenous ligand of the growth hormone secretagogue receptor (GHSR) and strongly stimulates the release of growth hormone from the hypothalamus–pituitary axis. Previous studies have identified the important physiological effects of ghrelin on bone metabolism, such as regulating proliferation and differentiation of osteoblasts, independent of GH/IGF-1 axis. However, research on effects and mechanisms of ghrelin on osteoblast apoptosis is still rare. In this study, we identified expression of GHSR in MC3T3-E1 cells and determined the effects of ghrelin on the apoptosis of osteoblastic MC3T3-E1 cells and the mechanism involved. Our data demonstrated that ghrelin inhibited the apoptosis of osteoblastic MC3T3-E1 cells induced by serum deprivation, as determined by terminal deoxynucleotidyl transferase-mediated deoxyribonucleotide triphosphate nick end-labeling (TUNEL) and ELISA assays. Moreover, ghrelin upregulated Bcl-2 expression and downregulated Bax expression in a dose-dependent manner. Our study also showed decreased activated caspase-3 activity under the treatment of ghrelin. Further study suggested that ghrelin stimulated the phosphorylation of ERK and AKT. Pretreatment of cells with the ERK inhibitor PD98059, PI3K inhibitor LY294002, and GHSR-siRNA blocked the ghrelin-induced activation of ERK and AKT, respectively; however, ghrelin did not stimulate the phosphorylation of p38 or JNK. PD90859, LY294002 and GHSR-siRNA attenuated the anti-apoptosis effect of ghrelin in MC3T3-E1 cells. In conclusion, ghrelin inhibits the apoptosis of osteoblastic MC3T3-E1 cells induced by serum deprivation, which may be mediated by activating the GHSR/ERK and GHSR/PI3K/AKT signaling pathways. - Highlights: • We explored the effects of ghrelin on serum deprivation-induced MC3T3-E1 cells apoptosis. • Both ELISA and TUNEL were used to detect the apoptosis. • The receptor of ghrelin, GHSR, was expressed in MC3T3-E1

  5. Association between Rare Variants in AP4E1, a Component of Intracellular Trafficking, and Persistent Stuttering.

    Science.gov (United States)

    Raza, M Hashim; Mattera, Rafael; Morell, Robert; Sainz, Eduardo; Rahn, Rachel; Gutierrez, Joanne; Paris, Emily; Root, Jessica; Solomon, Beth; Brewer, Carmen; Basra, M Asim Raza; Khan, Shaheen; Riazuddin, Sheikh; Braun, Allen; Bonifacino, Juan S; Drayna, Dennis

    2015-11-05

    Stuttering is a common, highly heritable neurodevelopmental disorder characterized by deficits in the volitional control of speech. Whole-exome sequencing identified two heterozygous AP4E1 coding variants, c.1549G>A (p.Val517Ile) and c.2401G>A (p.Glu801Lys), that co-segregate with persistent developmental stuttering in a large Cameroonian family, and we observed the same two variants in unrelated Cameroonians with persistent stuttering. We found 23 other rare variants, including predicted loss-of-function variants, in AP4E1 in unrelated stuttering individuals in Cameroon, Pakistan, and North America. The rate of rare variants in AP4E1 was significantly higher in unrelated Pakistani and Cameroonian stuttering individuals than in population-matched control individuals, and coding variants in this gene are exceptionally rare in the general sub-Saharan West African, South Asian, and North American populations. Clinical examination of the Cameroonian family members failed to identify any symptoms previously reported in rare individuals carrying homozygous loss-of-function mutations in this gene. AP4E1 encodes the ε subunit of the heterotetrameric (ε-β4-μ4-σ4) AP-4 complex, involved in protein sorting at the trans-Golgi network. We found that the μ4 subunit of AP-4 interacts with NAGPA, an enzyme involved in the synthesis of the mannose 6-phosphate signal that targets acid hydrolases to the lysosome and the product of a gene previously associated with stuttering. These findings implicate deficits in intracellular trafficking in persistent stuttering.

  6. The Role of CYP2E1 in the Drug Metabolism or Bioactivation in the Brain

    Science.gov (United States)

    García-Suástegui, W. A.; Ramos-Chávez, L. A.; Rubio-Osornio, M.; Calvillo-Velasco, M.; Atzin-Méndez, J. A.; Guevara, J.

    2017-01-01

    Organisms have metabolic pathways that are responsible for removing toxic agents. We always associate the liver as the major organ responsible for detoxification of the body; however this process occurs in many tissues. In the same way, as in the liver, the brain expresses metabolic pathways associated with the elimination of xenobiotics. Besides the detoxifying role of CYP2E1 for compounds such as electrophilic agents, reactive oxygen species, free radical products, and the bioactivation of xenobiotics, CYP2E1 is also related in several diseases and pathophysiological conditions. In this review, we describe the presence of phase I monooxygenase CYP2E1 in regions of the brain. We also explore the conditions where protein, mRNA, and the activity of CYP2E1 are induced. Finally, we describe the relation of CYP2E1 in brain disorders, including the behavioral relations for alcohol consumption via CYP2E1 metabolism. PMID:28163821

  7. The Role of CYP2E1 in the Drug Metabolism or Bioactivation in the Brain

    Directory of Open Access Journals (Sweden)

    W. A. García-Suástegui

    2017-01-01

    Full Text Available Organisms have metabolic pathways that are responsible for removing toxic agents. We always associate the liver as the major organ responsible for detoxification of the body; however this process occurs in many tissues. In the same way, as in the liver, the brain expresses metabolic pathways associated with the elimination of xenobiotics. Besides the detoxifying role of CYP2E1 for compounds such as electrophilic agents, reactive oxygen species, free radical products, and the bioactivation of xenobiotics, CYP2E1 is also related in several diseases and pathophysiological conditions. In this review, we describe the presence of phase I monooxygenase CYP2E1 in regions of the brain. We also explore the conditions where protein, mRNA, and the activity of CYP2E1 are induced. Finally, we describe the relation of CYP2E1 in brain disorders, including the behavioral relations for alcohol consumption via CYP2E1 metabolism.

  8. Inhibitory Potency of 4-Carbon Alkanes and Alkenes toward CYP2E1 Activity

    OpenAIRE

    2014-01-01

    CYP2E1 has been implicated in the bioactivation of many small molecules into reactive metabolites which form adducts with proteins and DNA, and thus a better understanding of the molecular determinants of its selectivity are critical for accurate toxicological predictions. In this study, we determined the potency of inhibition of human CYP2E1 for various 4-carbon alkanes, alkenes and alcohols. In addition, known CYP2E1 substrates and inhibitors including 4-methylpyrazole, aniline, and dimethy...

  9. 26 CFR 1.1059(e)-1 - Non-pro rata redemptions.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Non-pro rata redemptions. 1.1059(e)-1 Section 1... (CONTINUED) INCOME TAXES Special Rules § 1.1059(e)-1 Non-pro rata redemptions. (a) In general. Section 1059(d... 1059(e)(1). For example, if a redemption of stock is not pro rata as to all shareholders, any...

  10. Absence of NR2E1 mutations in patients with aniridia

    DEFF Research Database (Denmark)

    Corso-Díaz, Ximena; Borrie, Adrienne E; Bonaguro, Russell;

    2012-01-01

    Nuclear receptor 2E1 (NR2E1) is a transcription factor with many roles during eye development and thus may be responsible for the occurrence of certain congenital eye disorders in humans. To test this hypothesis, we screened NR2E1 for candidate mutations in patients with aniridia and other congen...... congenital ocular malformations (anterior segment dysgenesis, congenital optic nerve malformation, and microphthalmia)....

  11. TROPHOBLASTIC β1 – GLYCOPROTEIN SYNTHESIS IN SEROPOSITIVE PREGNANT WOMEN

    Directory of Open Access Journals (Sweden)

    R. N. Bogdanovich

    2005-01-01

    Full Text Available Abstract. The level of trophoblastic β1 – glycoprotein (SP–1 was determined in the blood sera of 200 healthy pregnant women and 184 women with threatened abortions in term till 20 weeks of pregnancy. In group of women experiencing recurrent abortions in 38 % cases antibodies to chorionic gonadotropin, in 39,5 % cases antibodies to phospholipids, in 25,5 % – antibodies to tireoglobulin were revealed in significant amounts. In 20,65 % lupus anticoagulant was found. The majority of women in this group had changes in homeostasis. The presence of autoantibodies during pregnancy is the unfavourable factor in the development of placental insufficiency. This is proved by the decreased secretion of trophoblastic β1 – glycoprotein – a marker of the fetal part of placenta. (Med. Immunol., 2005, vol.7, № 1, pp. 85588

  12. Incorporation of Spike and Membrane Glycoproteins into Coronavirus Virions

    Directory of Open Access Journals (Sweden)

    Makoto Ujike

    2015-04-01

    Full Text Available The envelopes of coronaviruses (CoVs contain primarily three proteins; the two major glycoproteins spike (S and membrane (M, and envelope (E, a non-glycosylated protein. Unlike other enveloped viruses, CoVs bud and assemble at the endoplasmic reticulum (ER-Golgi intermediate compartment (ERGIC. For efficient virion assembly, these proteins must be targeted to the budding site and to interact with each other or the ribonucleoprotein. Thus, the efficient incorporation of viral envelope proteins into CoV virions depends on protein trafficking and protein–protein interactions near the ERGIC. The goal of this review is to summarize recent findings on the mechanism of incorporation of the M and S glycoproteins into the CoV virion, focusing on protein trafficking and protein–protein interactions.

  13. Comparison of glycoprotein expression between ovarian and colon adenocarcinomas

    DEFF Research Database (Denmark)

    Multhaupt, H A; Arenas-Elliott, C P; Warhol, M J

    1999-01-01

    OBJECTIVE: Tumor-associated antigens may be expressed as surface glycoproteins. These molecules undergo qualitative and quantitative modifications during cell differentiation and malignant transformation. During malignant transformation, incomplete glycosylation is common, and certain glycosylation...... pathways are preferred. These antigens might help distinguish between ovarian and colonic adenocarcinomas in the primary and metastatic lesions. Different cytokeratins have been proposed as relatively organ-specific antigens. DESIGN: We used monoclonal antibodies against T1, Tn, sialosyl-Tn, B72.3, CA125......, carcinoembryonic antigen, and cytokeratins 7 and 20 to detect tumor-associated glycoproteins and keratin proteins in ovarian and colonic carcinomas. RESULTS: CA125, carcinoembryonic antigen, and cytokeratins 7 and 20 can distinguish between colonic and serous or endometrioid adenocarcinomas of the ovary in both...

  14. Rheologic studies on middle ear effusions and their mucus glycoproteins.

    Science.gov (United States)

    FitzGerald, J E; Green, G G; Birchall, J P; Pearson, J P

    1989-04-01

    The properties of pooled thick and thin middle ear effusions, from children with otitis media with effusion, were studied by viscometry. Mucus glycoproteins were responsible for effusion viscosity. Their percentage by weight in thick and thin effusions was 25% and 8.2%, respectively. N-acetylcysteine and 0.2 mol/L of mercaptoethanol caused a 39% viscosity drop in a 5-mg/mL glycoprotein solution, whereas S-carboxymethylcysteine had no effect. Treatment of thick effusions with 0.2 mol/L of mercaptoethanol initially caused a viscosity decrease followed by a gradual increase. Higher reducing agent concentrations (0.5 mol/L) caused a more rapid decrease followed by a rapid increase, presumably by causing nonspecific aggregation of reduced protein molecules. These results suggest that the concentration of and the time that a mucolytic is in the middle ear would be of prime importance in achieving the desired decrease in viscosity.

  15. CYP2E1-dependent hepatotoxicity and oxidative damage after ethanol administration in human primary hepatocytes

    Institute of Scientific and Technical Information of China (English)

    Lie-Gang Liu; Hong Yan; Ping Yao; Wen Zhang; Li-Jun Zou; Fang-Fang Song; Ke Li; Xiu-Fa Sun

    2005-01-01

    AIM: To observe the relationship between ethanol-induced oxidative damage in human primary cultured hepatocytes and cytochrome P450 2E1 (CYP2E1) activity, in order to address if inhibition of CYP2E1 could attenuate ethanol-induced cellular damage.METHODS: The dose-dependent (25-100 mmol/L) and time-dependent (0-24 h) exposures of primary human cultured hepatocytes to ethanol were carried out. CYP2E1 activity and protein expression were detected by spectrophotometer and Western blot analysis respectively.Hepatotoxicity was investigated by determination of lactate dehydrogenase (LDH) and aspartate transaminase (AST) level in hepatocyte culture supernatants, as well as the intracellular formation of malondialdehyde (MDA).RESULTS: A dose-and time-dependent response between ethanol exposure and CYP2E1 activity in human hepatocytes was demonstrated. Moreover, there was a time-dependent increase of CYP2E1 protein after 100 mmol/L ethanol exposure. Meanwhile, ethanol exposure of hepatocytes caused a time-dependent increase of ceilular MDA level, LDH, and AST activities in supernatants.Furthermore, the inhibitor of CYP2E1, diallyl sulfide (DAS) could partly attenuate the increases of MDA, LDH, and AST in human hepatocytes.CONCLUSION: A positive relationship between ethanol-induced oxidative aamage in human primary cultured hepatocytes and CYP2E1 activity was exhibited, and the inhibition of CYP2E1 could partly attenuate ethanol-induced oxidative damage.

  16. Requirements for E1A dependent transcription in the yeast Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Mymryk Joe S

    2009-04-01

    Full Text Available Abstract Background The human adenovirus type 5 early region 1A (E1A gene encodes proteins that are potent regulators of transcription. E1A does not bind DNA directly, but is recruited to target promoters by the interaction with sequence specific DNA binding proteins. In mammalian systems, E1A has been shown to contain two regions that can independently induce transcription when fused to a heterologous DNA binding domain. When expressed in Saccharomyces cerevisiae, each of these regions of E1A also acts as a strong transcriptional activator. This allows yeast to be used as a model system to study mechanisms by which E1A stimulates transcription. Results Using 81 mutant yeast strains, we have evaluated the effect of deleting components of the ADA, COMPASS, CSR, INO80, ISW1, NuA3, NuA4, Mediator, PAF, RSC, SAGA, SAS, SLIK, SWI/SNF and SWR1 transcriptional regulatory complexes on E1A dependent transcription. In addition, we examined the role of histone H2B ubiquitylation by Rad6/Bre1 on transcriptional activation. Conclusion Our analysis indicates that the two activation domains of E1A function via distinct mechanisms, identify new factors regulating E1A dependent transcription and suggest that yeast can serve as a valid model system for at least some aspects of E1A function.

  17. Identification and characterization of multiple conserved nuclear localization signals within adenovirus E1A

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Kris S.; Cohen, Michael J.; Fonseca, Greg J.; Todorovic, Biljana; King, Cason R. [Department of Microbiology and Immunology, Western University, London Regional Cancer Program, London, ON, Canada N6A 4L6 (Canada); Yousef, Ahmed F. [Department of Chemical and Environmental Engineering, Masdar Institute, Abu Dhabi (United Arab Emirates); Zhang, Zhiying [College of Animal Science and Technologies, Northwest A and F University, Yangling, Shaanxi 712100 (China); Mymryk, Joe S., E-mail: jmymryk@uwo.ca [Department of Microbiology and Immunology, Western University, London Regional Cancer Program, London, ON, Canada N6A 4L6 (Canada); Department of Oncology, Western University, London Regional Cancer Program, London, ON, Canada N6A 4L6 (Canada)

    2014-04-15

    The human adenovirus 5 (HAdV-5) E1A protein has a well defined canonical nuclear localization signal (NLS) located at its C-terminus. We used a genetic assay in the yeast Saccharomyces cerevisiae to demonstrate that the canonical NLS is present and functional in the E1A proteins of each of the six HAdV species. This assay also detects a previously described non-canonical NLS within conserved region 3 and a novel active NLS within the N-terminal/conserved region 1 portion of HAdV-5 E1A. These activities were also present in the E1A proteins of each of the other five HAdV species. These results demonstrate that, despite substantial differences in primary sequence, HAdV E1A proteins are remarkably consistent in that they contain one canonical and two non-canonical NLSs. By utilizing independent mechanisms, these multiple NLSs ensure nuclear localization of E1A in the infected cell. - Highlights: • HAdV E1A uses multiple mechanisms for nuclear import. • We identified an additional non-canonical NLS in the N-terminal/CR1 portion of E1A. • The new NLS does not contact importin-alpha directly. • All NLSs are functionally conserved in the E1A proteins of all 6 HAdV species.

  18. Identification of Aptamer-Binding Sites in Hepatitis C Virus Envelope Glycoprotein E2

    Directory of Open Access Journals (Sweden)

    Fan Chen

    2015-01-01

    Full Text Available Hepatitis C Virus (HCV encodes two envelope glycoproteins, E1 and E2. Our previous work selected a specific aptamer ZE2, which could bind to E2 with high affinity, with a great potential for developing new molecular probes as an early diagnostic reagents or therapeutic drugs targeting HCV. In this study, the binding sites between E2 and aptamer ZE2 were further explored. E2 was truncated to 15 peptides (P1 to P15 and these peptides were used to detect the affinity with ZE2 by ELISA respectively. The peptide with high affinity was then further truncated, detected and compared with six kinds of HCV genotypes. The basic amino acid in 500 aa bound to ZE2 with high affinity, while acidic amino acid in 501 aa reduced the reaction between E2 and ZE2. The results showed the 500 aa and 501 aa of E2 were the key sites that bound to ZE2.

  19. An analysis of amino acid sequences surrounding archaeal glycoprotein sequons

    OpenAIRE

    Mehtap Abu-Qarn; Jerry Eichler

    2006-01-01

    Despite having provided the first example of a prokaryal glycoprotein, little is known of the rules governing the N-glycosylation process in Archaea. As in Eukarya and Bacteria, archaeal N-glycosylation takes place at the Asn residues of Asn-X-Ser/Thr sequons. Since not all sequons are utilized, it is clear that other factors, including the context in which a sequon exists, affect glycosylation efficiency. As yet, t...

  20. Method for analysing glycoprotein isoforms by capillary electrophoresis

    OpenAIRE

    Frutos, Mercedes de; Díez-Masa, José Carlos; Morales-Cid, Gabriel

    2011-01-01

    [EN] The present invention relates to a new method for the purification, concentration, separation and determination of the isoforms of alpha-1-acid glycoprotein (AGP) in human blood serum samples using capillary electrophoresis. The new method is based on the immunocapture and preconcentration of the sample within the separation capillary by using an immunoadsorbent phase magnetically immobilized within the electrophoresis capillary and the subsequent desorption and separation of the glycopr...

  1. Pneumocystis carinii glycoprotein A binds macrophage mannose receptors.

    OpenAIRE

    O'Riordan, D.M.; Standing, J E; Limper, A H

    1995-01-01

    Pneumocystis carinii causes life-threatening pneumonia in patients with impaired immunity. Recent studies suggest that alveolar macrophages interact with P. carinii through macrophage mannose receptors. However, the ligand(s) on P. carinii that is recognized by these receptors has not been fully defined. P. carinii contains a major mannose-rich surface antigen complex termed glycoprotein A (gpA). It was therefore hypothesized that gpA binds directly to macrophage mannose receptors and mediate...

  2. Isolation of a surface glycoprotein from Myxococcus xanthus.

    OpenAIRE

    Maeba, P Y

    1986-01-01

    The isolation of a glycoprotein from vegetative cells of Myxococcus xanthus is reported. The protein, abbreviated VGP, was first identified during a survey of surface proteins as a major protein that could be radioiodinated in vegetative, but not developing, cells (P.Y. Maeba, J. Bacteriol. 155:1033-1041, 1983). The protein was extracted from membranes with Triton X-100 and subsequently purified by DEAE-cellulose chromatography, chromatofocusing, and gel filtration. The protein has an Mr of a...

  3. Antibody Derived Peptides for Detection of Ebola Virus Glycoprotein

    OpenAIRE

    Luis Mario Rodríguez-Martínez; Alan Roberto Marquez-Ipiña; Felipe López-Pacheco; Roberto Pérez-Chavarría; Juan Carlos González-Vázquez; Everardo González-González; Grissel Trujillo-de Santiago; César Alejandro Ponce-Ponce de León; Yu Shrike Zhang; Mehmet Remzi Dokmeci; Ali Khademhosseini; Mario Moisés Alvarez

    2015-01-01

    Background: Current Ebola virus (EBOV) detection methods are costly and impractical for epidemic scenarios. Different immune-based assays have been reported for the detection and quantification of Ebola virus (EBOV) proteins. In particular, several monoclonal antibodies (mAbs) have been described that bind the capsid glycoprotein (GP) of EBOV GP. However, the currently available platforms for the design and production of full-length mAbs are cumbersome and costly. The use of antibody fragment...

  4. Microarray-based analysis and clinical validation identify ubiquitin-conjugating enzyme E2E1 (UBE2E1 as a prognostic factor in acute myeloid leukemia

    Directory of Open Access Journals (Sweden)

    Hongmei Luo

    2016-11-01

    Full Text Available Abstract Background Previous research suggested that single gene expression might be correlated with acute myeloid leukemia (AML survival. Therefore, we conducted a systematical analysis for AML prognostic gene expressions. Methods We performed a microarray-based analysis for correlations between gene expression and adult AML overall survival (OS using datasets GSE12417 and GSE8970. Positive findings were validated in an independent cohort of 50 newly diagnosed, non-acute promyelocytic leukemia (APL AML patients by quantitative RT-PCR and survival analysis. Results Microarray-based analysis suggested that expression of eight genes was each associated with 1-year and 3-year AML OS in both GSE12417 and GSE8970 datasets (p < 0.05. Next, we validated our findings in an independent cohort of AML samples collected in our hospital. We found that ubiquitin-conjugating enzyme E2E1 (UBE2E1 expression was adversely correlated with AML survival (p = 0.04. Multivariable analysis showed that UBE2E1 high patients had a significant shorter OS and shorter progression-free survival after adjusting other known prognostic factors (p = 0.03. At last, we found that UBE2E1 expression was negatively correlated with patients’ response to induction chemotherapy (p < 0.05. Conclusions In summary, we demonstrated that UBE2E1 expression was a novel prognostic factor in adult, non-APL AML patients.

  5. Cellular and biophysical evidence for interactions between adenosine triphosphate and P-glycoprotein substrates

    DEFF Research Database (Denmark)

    Abraham, E H; Shrivastav, B; Salikhova, A Y

    2001-01-01

    P-glycoprotein is involved with the removal of drugs, most of them cations, from the plasma membrane and cytoplasm. Pgp is also associated with movement of ATP, an anion, from the cytoplasm to the extracellular space. The central question of this study is whether drug and ATP transport associated...... with the expression of Pgp are in any way coupled. We have measured the stoichiometry of transport coupling between drug and ATP release. The drug and ATP transport that is inhibitable by the sulfonylurea compound, glyburide (P. E. Golstein, A. Boom, J. van Geffel, P. Jacobs, B. Masereel, and R. Beauwens, Pfluger......'s Arch. 437, 652, 1999), permits determination of the transport coupling ratio, which is close to 1:1. In view of this result, we asked whether ATP interacts directly with Pgp substrates. We show by measuring the movement of Pgp substrates in electric fields that ATP and drug movement are coupled...

  6. Blood-brain barrier P-glycoprotein function in neurodegenerative disease.

    Science.gov (United States)

    Bartels, A L

    2011-01-01

    Protection of the brain is strengthened by active transport and ABC transporters. P-glycoprotein (P-gp) at the blood-brain barrier (BBB) functions as an active efflux pump by extruding a substrate from the brain, which is important for maintaining loco-regional homeostasis in the brain and protection against toxic compounds. Importantly, dysfunctional BBB P-gp transport is postulated as an important factor contributing to accumulation of aggregated protein in neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD). Furthermore, P-gp is a major factor in mediating resistance to brain entry of numerous exogenous compounds, including toxins that can be involved in PD pathogenesis. This review highlights the role of altered P-gp function in the pathogenesis and progression of neurodegenerative disease. Also the implications of alterations in P-gp function for the treatment of these diseases are discussed.

  7. Docking Applied to the Prediction of the Affinity of Compounds to P-Glycoprotein

    Directory of Open Access Journals (Sweden)

    Pablo H. Palestro

    2014-01-01

    Full Text Available P-glycoprotein (P-gp is involved in the transport of xenobiotic compounds and responsible for the decrease of the drug accumulation in multi-drug-resistant cells. In this investigation we compare several docking algorithms in order to find the conditions that are able to discriminate between P-gp binders and nonbinders. We built a comprehensive dataset of binders and nonbinders based on a careful analysis of the experimental data available in the literature, trying to overcome the discrepancy noticeable in the experimental results. We found that Autodock Vina flexible docking is the best choice for the tested options. The results will be useful to filter virtual screening results in the rational design of new drugs that are not expected to be expelled by P-gp.

  8. Learning disability and oligodendrocyte myelin glycoprotein (OMGP) gene in neurofibromatosis type 1.

    Science.gov (United States)

    Terzi, Yunus Kasim; Oğuzkan-Balci, Sibel; Anlar, Banu; Erdoğan-Bakar, Emel; Ayter, Sükriye

    2011-01-01

    Neurofibromatosis type 1 (NF1) is an autosomal dominant disease where phenotypic heterogeneity is explained by the effect of modifier genes. Thirty to 65% of patients have learning disability. The oligodendrocyte myelin glycoprotein (OMGP) gene located within the neurofibromatosis type 1 (NF1) gene might affect the phenotype of learning disability because it is expressed in the brain, and OMGP gene mutations have been associated with cognitive disturbances. We analyzed the OMGP gene in NF1 patients with and without learning disability (n = 50 each) and healthy controls (n = 100). The allele distribution of OMGP62 polymorphism was not significantly different between the groups (p = 0.447). These results do not support a relationship between the OMGP gene and the learning disability phenotype observed in NF1. Other modifying genes, post-translational modifications or receptor interactions might be involved in the phenotypic variability of NF1.

  9. Evolution of human alpha 1-acid glycoprotein genes and surrounding Alu repeats.

    Science.gov (United States)

    Merritt, C M; Easteal, S; Board, P G

    1990-04-01

    There is a mosaic pattern of variation between the two tandemly arranged human alpha 1-acid glycoprotein genes. Both the synonymous and the nonsynonymous sites of exons 3 and 4 are more divergent than the rest of the gene, suggesting that they have had a different evolutionary history. Comparisons of the two gene sequences with rat AGP indicate that exons 3 and 4 of AGP2 have been evolving without functional constraint since their divergence from AGP1. It is proposed that the conserved region of the gene has been homogenized recently by gene conversion with the homologous regions of AGP1. The Alu sequences surrounding the genes appear to have been involved in both the gene duplication and the gene conversion events.

  10. A double responsive smart upconversion fluorescence sensing material for glycoprotein.

    Science.gov (United States)

    Guo, Ting; Deng, Qiliang; Fang, Guozhen; Yun, Yaguang; Hu, Yongjin; Wang, Shuo

    2016-11-15

    A novel strategy was developed to prepare double responsive smart upconversion fluorescence material for highly specific enrichment and sensing of glycoprotein. The novel double responsive smart sensing material was synthesized by choosing Horse radish peroxidase (HRP) as modal protein, the grapheme oxide (GO) as support material, upconversion nanoparticles (UCNPs) as fluorescence signal reporter, N-isopropyl acrylamide (NIPAAM) and 4-vinylphenylboronic acid (VPBA) as functional monomers. The structure and component of smart sensing material was investigated by transmission electron microscopy (TEM), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopic (XPS) and Fourier transform infrared (FTIR), respectively. These results illustrated the smart sensing material was prepared successfully. The recognition characterizations of smart sensing material were evaluated, and results showed that the fluorescence intensity of smart sensing material was reduced gradually, as the concentration of protein increased, and the smart sensing material showed selective recognition for HRP among other proteins. Furthermore, the recognition ability of the smart sensing material for glycoprotein was regulated by controlling the pH value and temperature. Therefore, this strategy opens up new way to construct smart material for detection of glycoprotein.

  11. Characterization of an estrogen-induced oviduct membrane glycoprotein

    Energy Technology Data Exchange (ETDEWEB)

    Poola, I.; Lucas, J.J.

    1986-05-01

    During estrogen-induced chick oviduct differentiation a number of N-linked membrane glycoproteins are induced as judged by GDP-(/sup 14/C)Man labeling of endogenous acceptors, /sup 125/I-con A labeling as well as coomassie blue and PAS staining of SDS polyacrylamide gels. The authors have begun to characterize one of these glycoproteins having an M/sub r/ of 91 KDa. The protein has been purified via preparative SDS-PAGE and electroelution. The purified protein migrates as a single band on analytical SDS-PAGE and comigrates with an endogenous membrane glycoprotein labeled with GDP-(/sup 14/C)Man. Amino acid analysis indicates a high proportion of GLU and ASP residues (110 and 66 moles respectively). N-terminal sequence analysis by gas phase instrumentation yielded the following: X-X-VAL-ASP-VAL-ASP-ALA-THR-VAL-GLU-GLU-ASP-GLU. The protein contains about 2% neutral sugar including 6 mol Man, 2 mol Gal, 1 mol Fuc, 4 mol GlcNAc, 1 mol GalNAc and 1 mol sialic acid per mole of protein. The presence of the GalNAc residue suggests the protein contains an O-linked oligosaccharide moiety in addition to the N-linked chain(s). The detailed structure of the carbohydrate moieties is currently under investigation.

  12. Australine, a pyrrolizidine alkaloid that inhibits amyloglucosidase and glycoprotein processing

    Energy Technology Data Exchange (ETDEWEB)

    Tropea, J.E.; Molyneux, R.J.; Kaushal, G.P.; Pan, Y.T.; Mitchell, M.; Elbein, A.D. (Univ. of Texas Health Science Center, San Antonio (USA))

    1989-03-07

    Australine is a polyhydroxylated pyrrolizidine alkaloid that was isolated from the seeds of the Australian tree Castanospermum australe and characterized by NMR and X-ray diffraction analysis. Since swainsonine and catanospermine are polyhydroxylated indolizidine alkaloids that inhibit specific glycosidases, the authors tested australine against a variety of exoglycosidases to determine whether it would inhibit any of these enzymes. This alkaloid proved to be a good inhibitor of the {alpha}-glucosidase amyloglucosidase (50% inhibition at 5.8 {mu}M), but it did not inhibit {beta}-glucosidase, {alpha}- or {beta}-mannosidase, or {alpha}- or {beta}-galactosidase. The inhibition of amyloglucosidase was of a competitive nature. Australine also inhibited the glycoprotein processing enzyme glucosidase I, but had only slight activity toward glucosidase II. When incubated with cultured cells, this alkaloid inhibited glycoprotein processing at the glucosidase I step and caused the accumulation of glycoproteins with Glc{sub 3}Man{sub 7-9}(GlcNAc){sub 2}-oligosaccharides.

  13. Glycoprotein fucosylation is increased in seminal plasma of subfertile men

    Directory of Open Access Journals (Sweden)

    Beata Olejnik

    2015-04-01

    Full Text Available Fucose, the monosaccharide frequent in N- and O-glycans, is a part of Lewis-type antigens that are known to mediate direct sperm binding to the zona pellucida. Such interaction was found to be inhibited in vitroby fucose-containing oligo- and polysaccharides, as well as neoglycoproteins. The objective of this study was to screen seminal plasma proteins of infertile/subfertile men for the content and density of fucosylated glycoepitopes, and compare them to samples of fertile normozoospermic subjects. Seminal proteins were separated in polyacrylamide gel electrophoresis and blotted onto nitrocellulose membrane and probed with fucose-specific Aleuria aurantia lectin (AAL. Twelve electrophoretic bands were selected for quantitative densitometric analysis. It was found that the content, and especially the density of fucosylated glycans, were higher in glycoproteins present in seminal plasma of subfertile men. No profound differences in fucosylation density were found among the groups of normozoospermic, oligozoospermic, asthenozoospermic, and oligoasthenozoospermic subfertile men. According to the antibody probing, AAL-reactive bands can be attributed to male reproductive tract glycoproteins, including prostate-specific antigen, prostatic acid phosphatase, glycodelin and chorionic gonadotropin. Fibronectin, α1 -acid glycoprotein, α1 -antitrypsin, immunoglobulin G and antithrombin III may also contribute to this high fucosylation. It is suggested that the abundant fucosylated glycans in the sperm environment could interfere with the sperm surface and disturb the normal course of the fertilization cascade.

  14. Platelet membrane glycoproteins and their function: an overview.

    Science.gov (United States)

    Kunicki, T J

    1989-07-01

    The membrane glycoproteins (GP) of human platelets act as receptors that mediate two important functions, adhesion to the subendothelial matrix and platelet-platelet cohesion, or aggregation. Many of these glycoprotein receptors exist as noncovalently linked heterodimers, including those that belong to the supergene family of adhesion receptors called the integrins. Human platelets contain at least five members of this integrin family, including a collagen receptor (GP Ia-IIa; alpha 2, beta 1), a fibronectin receptor (GP Ic-IIa; alpha 5, beta 1), a laminin receptor (GP Ic'-IIa; alpha 6, beta 1), a vitronectin receptor (VnR; alpha v, beta 3), and a promiscuous, activation-dependent receptor that is thought to be the receptor most responsible for fibrinogen-dependent, platelet-platelet cohesion (GP IIb-IIIa; alpha IIb, beta 3). Some, but not all, of the integrins bind to a tripeptide sequence, arginine-glycine-aspartic acid (RGD), on the adhesive proteins. In addition to the integrins, platelets contain other membrane glyco-proteins: GP Ib-IX, a receptor for von Willebrand factor, which is thought to be the receptor most responsible for platelet adhesion to the subendothelial matrix in a flowing system; GP V, which may be associated with GP Ib-IX and whose function remains unknown; and GP IV (GP IIIb), which functions as a receptor for thrombospondin and collagen.

  15. Effect of glucocorticoid on prostaglandin E1 mediated cyclic AMP formation by vascular smooth muscle cells.

    Science.gov (United States)

    Yasunari, K; Kohno, M; Murakawa, K; Yokokawa, K; Takeda, T

    1988-12-01

    The effect of glucocorticoid on the prostaglandin E1 (PGE1)-mediated cyclic AMP (cAMP) formation by vascular smooth muscle cells (VSMC) from renal arteries (RA) was studied in rats. Dexamethasone (DEX) at concentrations ranging from 10(-10) to approximately 10(-8) mol/l dose-dependently potentiates the PGE1-mediated response. This facilitation began at 6 h and reached its maximum after 24 h of DEX administration. Aldosterone (10(-6) mol/l) did not affect the dose-response curve of PGE1. Inhibitors of protein and RNA synthesis blocked this glucocorticoid effect. The basal activity of adenylate cyclase in DEX-treated cells was twice as high as in control cells. Treatment of VSMC with DEX increased cholera toxin- and pertussis toxin-stimulated adenylate cyclase activity. DEX treatment also augments forskolin-stimulated adenylate cyclase activity. These results suggest that DEX increases PGE1-mediated cAMP formation of VSMC from RA through a mechanism that involves the induction of protein synthesis, and that the activation of the catalytic unit may play some role in this facilitating process.

  16. CYP2E1, oxidative stress, post-translational modifications and lipid metabolism.

    Science.gov (United States)

    Lakshman, M Raj; Garige, Mamatha; Gong, Maokai A; Leckey, Leslie; Varatharajalu, Ravi; Redman, Robert S; Seth, Devanshi; Haber, Paul S; Hirsch, Kenneth; Amdur, Richard; Shah, Ruchi

    2013-01-01

    Chronic alcohol-mediated down-regulation of hepatic ST6Gal1 gene leads to defective glycosylation of lipid-carrying apolipoproteins such as apo E and apo J, resulting in defective VLDL assembly and intracellular lipid and lipoprotein transport, which in turn is responsible for alcoholic hepatosteatosis and ALD. The mechanism of ethanol action involves thedepletion of a unique RNA binding protein that specifically interacts with its 3'-UTR region of ST6Gal1 mRNA resulting in its destabilization and consequent appearance of asialoconjugates as alcohol biomarkers. With respect to ETOH effects on Cardio-Vascular Diseases, we conclude that CYP2E1 and ETOH mediated oxidative stress significantly down regulates not only the hepatic PON1 gene expression, but also serum PON1 and HCTLase activities accompanied by depletion of hepatic GSH, the endogenous antioxidant. These results strongly implicate the susceptibility of PON1 to increased ROS production. In contrast, betaine seems to be both hepatoprotective and atheroprotective by reducing hepatosteatosis and restoring not only liver GSH that quenches free radicals, but also the antiatherogenic PON1 gene expression and activity.

  17. Characteristics and Soft-Demodulation of Galileo E1 Signal%Galileo E1信号特征及其软件解调

    Institute of Scientific and Technical Information of China (English)

    易翔

    2009-01-01

    Galileo E1民用信号采用新的BOC(1,1)扩频调制方式.针对E1信号进行信号建模,并对其信号特征进行了详细研究,最后设计了Galileo软件解调器中的信号处理模块.通过仿真验证表明,软件解调器成功实现了对Galileo E1信号的捕获、跟踪、解扩、解调全过程处理,克服了BOC解调的错锁问题.

  18. Community involvement

    Directory of Open Access Journals (Sweden)

    Editorial Office

    1979-09-01

    Full Text Available Community involvement is the main theme of Health Year. Governments have a responsibility for the health of their people, and in this country under the present 3-tier system of government, the responsibility for the rendering of health services is divided between central, provincial and local government. However, under our democratic system, all people have the right to, and it is indeed their duty, to participate individually and collectively in the planning and implementation of services to meet their health needs. Ultimately, through involvement of individuals, families and communities, greater self-reliance is achieved leading to greater responsibility being assumed by people for their own health.

  19. 26 CFR 1.669(e)-1A - Pro rata portion of taxes deemed distributed.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Pro rata portion of taxes deemed distributed. 1.669(e)-1A Section 1.669(e)-1A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Treatment of Excess Distributions of Trusts Applicable to Taxable Years Beginning Before January...

  20. Expression of cytochrome P4502E1 gene in hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Xiao-Bo Man; Liang Tang; Xiu-Hua Qiu; Li-Qun Yang; Hui-Fang Cao; Meng-Chao Wu; Hong-Yang Wang

    2004-01-01

    AIM: To investigate cytpchrome P4502E1 ( CYP2E1) gene expression in occurrence and progression of hepatocellular carcinoma (HCC).METHODS: The human liver arrayed library was spotted onto the nylon membranes to make cDNA array. Hybridization of cDNA array was performed with labeled probes synthesized from RNA isolated from HCC and adjacent liver tissues.Sprague-Dawley rats were administrated diethylnitrosamine (DENA) to induce HCC. CYP2E1 expression was detected by the method of RT-PCR and Northern blot analysis.RESULTS: CYP2E1 was found by cDNA array hybridization to express differently between HCC and liver tissues. CYP2E1only expressed in liver, but did not express in HCC tissues and expressed lowly in cirrhotic tissues. In the progression of cirrhosis and HCC, the expression level of CYP2E1 was gradually decreased and hardly detected until the late stage of HCC.CONCLUSION: Using arrayed library to make cDNA arrays is an effective method to find differential expression genes.CYP2E1 is a unique gene expressing in liver but did not express in HCC. CYP2E1 expression descended along with the initiation and progression of HCC, which is noteworthy further investigations in its significance in the development of HCC.

  1. Morbidly Obese Patients Exhibit Increased CYP2E1-Mediated Oxidation of Acetaminophen

    NARCIS (Netherlands)

    A. van Rongen (Anne); P.A.J. Välitalo (Pyry A. J.); M.Y. Peeters (Mariska); D. Boerma (Djamila); F.W. Huisman (Fokko W.); B. van Ramshorst (Bert); E.H.P.A. van Dongen (Eric); J.N. van den Anker (John); C.A.J. Knibbe (Catherijne)

    2016-01-01

    textabstractIntroduction: Acetaminophen (paracetamol) is mainly metabolized via glucuronidation and sulphation, while the minor pathway through cytochrome P450 (CYP) 2E1 is held responsible for hepatotoxicity. In obese patients, CYP2E1 activity is reported to be induced, thereby potentially worsenin

  2. Morbidly Obese Patients Exhibit Increased CYP2E1-Mediated Oxidation of Acetaminophen.

    NARCIS (Netherlands)

    Rongen, van A.; Välitalo, P.A.J.; Peeters, M.Y.; Boerma, D.; Huisman, F.W.; Ramshorst, van B.; Dongen, van E.P.; Anker, van den J.N.; Knibbe, C.A.J.

    2016-01-01

    INTRODUCTION Acetaminophen (paracetamol) is mainly metabolized via glucuronidation and sulphation, while the minor pathway through cytochrome P450 (CYP) 2E1 is held responsible for hepatotoxicity. In obese patients, CYP2E1 activity is reported to be induced, thereby potentially worsening the safety

  3. CK2 phosphorylation inactivates DNA binding by the papillomavirus E1 and E2 proteins.

    Science.gov (United States)

    Schuck, Stephen; Ruse, Cristian; Stenlund, Arne

    2013-07-01

    Papillomaviruses have complex life cycles that are understood only superficially. Although it is well established that the viral E1 and E2 proteins play key roles in controlling viral transcription and DNA replication, how these factors are regulated is not well understood. Here, we demonstrate that phosphorylation by the protein kinase CK2 controls the biochemical activities of the bovine papillomavirus E1 and E2 proteins by modifying their DNA binding activity. Phosphorylation at multiple sites in the N-terminal domain in E1 results in the loss of sequence-specific DNA binding activity, a feature that is also conserved in human papillomavirus (HPV) E1 proteins. The bovine papillomavirus (BPV) E2 protein, when phosphorylated by CK2 on two specific sites in the hinge, also loses its site-specific DNA binding activity. Mutation of these sites in E2 results in greatly increased levels of latent viral DNA replication, indicating that CK2 phosphorylation of E2 is a negative regulator of viral DNA replication during latent viral replication. In contrast, mutation of the N-terminal phosphorylation sites in E1 has no effect on latent viral DNA replication. We propose that the phosphorylation of the N terminus of E1 plays a role only in vegetative viral DNA replication, and consistent with such a role, caspase 3 cleavage of E1, which has been shown to be necessary for vegetative viral DNA replication, restores the DNA binding activity to phosphorylated E1.

  4. 26 CFR 1.665(e)-1A - Preceding taxable year.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Preceding taxable year. 1.665(e)-1A Section 1... (CONTINUED) INCOME TAXES Treatment of Excess Distributions of Trusts Applicable to Taxable Years Beginning on Or After January 1, 1969 § 1.665(e)-1A Preceding taxable year. (a) Definition—(1) Domestic trusts—(i...

  5. 26 CFR 31.3121(e)-1 - State, United States, and citizen.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 15 2010-04-01 2010-04-01 false State, United States, and citizen. 31.3121(e)-1... § 31.3121(e)-1 State, United States, and citizen. (a) When used in the regulations in this subpart, the... is used in a geographical sense. The term “citizen of the United States” includes a citizen of the...

  6. Effects of glycoprotein Ⅱb/Ⅲa antagonists and chloride channel blockers on platelet cytoplasmic free calcium

    Institute of Scientific and Technical Information of China (English)

    YIN Song-mei; XIE Shuang-feng; NIE Da-nian; LI Yi-qing; LI Hai-ming; MA Li-ping; WANG Xiu-ju; WU Yu-dan; FENG Jian-hong

    2005-01-01

    @@ Platelet activation plays an important role in thrombosis. Platelet glycoprotein Ⅱb/Ⅲa (GP Ⅱb/Ⅲa) is the receptor of fibrinogen. Platelet cross-linking with fibrinogen through GPⅡb/Ⅲa is the process of thrombosis. Ca2+ is an important intracellular second messenger in platelet activation. It has been reported that GPⅡb/Ⅲa receptors were involved in the calcium influx of activated platelet, and GPⅡb/Ⅲa receptor had characteristics of calcium channel or an adjacent calcium channel.

  7. Structural basis for Epstein–Barr virus host cell tropism mediated by gp42 and gHgL entry glycoproteins

    Science.gov (United States)

    Sathiyamoorthy, Karthik; Hu, Yao Xiong; Möhl, Britta S.; Chen, Jia; Longnecker, Richard; Jardetzky, Theodore S.

    2016-01-01

    Herpesvirus entry into host cells is mediated by multiple virally encoded receptor binding and membrane fusion glycoproteins. Despite their importance in host cell tropism and associated disease pathology, the underlying and essential interactions between these viral glycoproteins remain poorly understood. For Epstein–Barr virus (EBV), gHgL/gp42 complexes bind HLA class II to activate membrane fusion with B cells, but gp42 inhibits fusion and entry into epithelial cells. To clarify the mechanism by which gp42 controls the cell specificity of EBV infection, here we determined the structure of gHgL/gp42 complex bound to an anti-gHgL antibody (E1D1). The critical regulator of EBV tropism is the gp42 N-terminal domain, which tethers the HLA-binding domain to gHgL by wrapping around the exterior of three gH domains. Both the gp42 N-terminal domain and E1D1 selectively inhibit epithelial-cell fusion; however, they engage distinct surfaces of gHgL. These observations clarify key determinants of EBV host cell tropism. PMID:27929061

  8. New Protein Vector ApE1 for Targeted Delivery of Anticancer Drugs

    Directory of Open Access Journals (Sweden)

    N. V. Pozdniakova

    2012-01-01

    Full Text Available A new chimeric gene ApE1 encoding the receptor-binding domain of the human alpha-fetoprotein fused to a sequence of 22 glutamic acid residues was constructed. A new bacterial producer strain E. coli SHExT7 ApE1 was selected for ApE1 production in a soluble state. A simplified method was developed to purify ApE1 from bacterial biomass. It was shown that the new vector protein selectively interacts with AFP receptors on the tumor cell surface and can be efficiently accumulated in tumor cells. In addition, ApE1 was shown to be stable in storage and during its chemical modification. An increased number of carboxyl groups in the molecule allows the production of cytotoxic compound conjugates with higher drug-loading capacity and enhanced tumor targeting potential.

  9. Sensitivity of P-glycoprotein tryptophan residues to benzodiazepines and ATP interaction.

    Science.gov (United States)

    Lima, Sofia A C; Cordeiro-da-Silva, Anabela; de Castro, Baltazar; Gameiro, Paula

    2007-01-01

    Plasma membrane P-glycoprotein is a member of the ATP-binding cassette family of membrane transporters. In the present study tryptophan intrinsic fluorescence was used to understand the P-glycoprotein response to three benzodiazepines (bromazepam, chlordiazepoxide and flurazepam) in the presence and absence of ATP. Fluorescence emission spectra showed a red shift on the maximal emission wavelength upon interaction of P-glycoprotein with all benzodiazepines. Benzodiazepine association with nucleotide-bound P-glycoprotein also showed this trend and the quenching profile was attributed to a sphere-of-action model, for static fluorescence. Furthermore, quenching data of benzodiazepine-bound P-glycoprotein with ATP were concentration dependent and saturable, indicating that nucleotide binds to P-glycoprotein whether drug is present or not. These results seems in agreement with the proposal of the ATP-switch model by Higgins and Linton, where substrate binding to the transporters initiates the transport cycle by increasing the ATP binding affinity.

  10. Functional expression of 5-HT{sub 2A} receptor in osteoblastic MC3T3-E1 cells

    Energy Technology Data Exchange (ETDEWEB)

    Hirai, Takao; Kaneshige, Kota; Kurosaki, Teruko [Department of Molecular Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, 1 Gakuen-cho, Fukuyama, Hiroshima 729-0292 (Japan); Nishio, Hiroaki, E-mail: nishio@fupharm.fukuyama-u.ac.jp [Department of Molecular Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, 1 Gakuen-cho, Fukuyama, Hiroshima 729-0292 (Japan)

    2010-05-28

    In the previous study, we reported the gene expression for proteins related to the function of 5-hydroxytryptamine (5-HT, serotonin) and elucidated the expression patterns of 5-HT{sub 2} receptor subtypes in mouse osteoblasts. In the present study, we evaluated the possible involvement of 5-HT receptor subtypes and its inactivation system in MC3T3-E1 cells, an osteoblast cell line. DOI, a 5-HT{sub 2A} and 5-HT{sub 2C} receptor selective agonist, as well as 5-HT concentration-dependently increased proliferative activities of MC3T3-E1 cells in their premature period. This effect of 5-HT on cell proliferation were inhibited by ketanserin, a 5-HT{sub 2A} receptor specific antagonist. Moreover, both DOI-induced cell proliferation and phosphorylation of ERK1 and 2 proteins were inhibited by PD98059 and U0126, selective inhibitors of MEK in a concentration-dependent manner. Furthermore, treatment with fluoxetine, a 5-HT specific re-uptake inhibitor which inactivate the function of extracellular 5-HT, significantly increased the proliferative activities of MC3T3-E1 cells in a concentration-dependent manner. Our data indicate that 5-HT fill the role for proliferation of osteoblast cells in their premature period. Notably, 5-HT{sub 2A} receptor may be functionally expressed to regulate mechanisms underlying osteoblast cell proliferation, at least in part, through activation of ERK/MAPK pathways in MC3T3-E1 cells.

  11. Cytochrome P450 2E1 is responsible for the initiation of 1,2-dichloropropane-induced liver damage.

    Science.gov (United States)

    Yanagiba, Yukie; Suzuki, Tetsuya; Suda, Megumi; Hojo, Rieko; Gonzalez, Frank J; Nakajima, Tamie; Wang, Rui-Sheng

    2016-09-01

    1,2-Dichloropropane (1,2-DCP), a solvent, which is the main component of the cleaner used in the offset printing companies in Japan, is suspected to be the causative agent of bile duct cancer, which has been recently reported at high incidence in those offset printing workplaces. While there are some reports about the acute toxicity of 1,2-DCP, no information about its metabolism related to toxicity in animals is available. As part of our efforts toward clarifying the role of 1,2-DCP in the development of cancer, we studied the metabolic pathways and the hepatotoxic effect of 1,2-DCP in mice with or without cytochrome P450 2E1 (CYP2E1) activity. In an in vitro reaction system containing liver homogenate, 1,2-DCP was only metabolized by liver tissue of wild-type mice but not by that of cyp2e1-null mice. Furthermore, the kinetics of the solvent in mice revealed a great difference between the two genotypes; 1,2-DCP administration resulted in dose-dependent hepatic damage, as shown biochemically and pathologically, but this effect was only observed in wild-type mice. The nuclear factor κB p52 pathway was involved in the liver response to 1,2-DCP. Our results clearly indicate that the oxidative metabolism of 1,2-DCP in mice is exclusively catalyzed by CYP2E1, and this step is indispensable for the manifestation of the hepatotoxic effect of the solvent.

  12. Construction of a mouse Aos1-Uba2 chimeric SUMO-E1 enzyme, mAU, and its expression in baculovirus-insect cells

    Science.gov (United States)

    Nakayama, Tomofumi; Yuasa, Eri; Kanemaru, Ayumi; Saito, Masayuki; Saitoh, Hisato

    2014-01-01

    Small ubiquitin-related modifier (SUMO) is a highly conserved protein that is covalently attached to target proteins. This posttranslational modification, designated SUMOylation, is a major protein-conjugation-driven strategy designed to regulate structure and function of cellular proteins. SUMOylation consists of an enzymatic cascade involving the E1-activating enzyme and the E2-conjugating enzyme. The SUMO-E1 enzyme consists of two subunits, a heterodimer of activation of Smt3p 1 (Aos1) and ubiquitin activating enzyme 2 (Uba2), which resembles the N- and C-terminal halves of ubiquitin E1 (Uba1). Herein, we describe the rational design of a single polypeptide version of SUMO-E1, a chimera of mouse Aos1 and Uba2 subunits, termed mAU, in which the functional domains appear to be arranged in a fashion similar to Uba1. We also describe the construction of a mAU plasmid for expression in a baculovirus-insect cell system and present an in situ SUMOylation assay using the recombinant mAU. Our results showed that mAU has SUMO-E1 activity, thereby indicating that mAU can be expressed in baculovirus-insect cells and represents a suitable source of SUMO-E1. PMID:24637489

  13. Antiphospholipid Syndrome and Kidney Involvement: New Insights

    Directory of Open Access Journals (Sweden)

    José A. Martínez-Flores

    2016-07-01

    Full Text Available Antiphospholipid syndrome is an autoimmune disorder characterized by vascular thromboses and pregnancy morbidity associated with antiphospholipid antibodies: lupus anticoagulant, IgG or IgM anticardiolipin or anti-beta 2-glycoprotein I. The kidney is one of the major target organs in antiphospholipid syndrome (APS. However, beyond the known involvement of the kidney in primary and associated APS, we may be observing a new form of APS within the context of renal failure. This review describes the classical kidney manifestations of APS and provides new considerations to be taken into account.

  14. Expression of the glycoprotein gene from a fish rhabdovirus by using baculovirus vectors

    Energy Technology Data Exchange (ETDEWEB)

    Koener, J.F.; Leong, J.A.C. (Oregon State Univ., Corvallis (United States))

    1990-01-01

    A cDNA fragment containing the gene encoding the glycoprotein of infectious hematopoietic necrosis virus was inserted into Autographa californica baculovirus vectors under the control of the polyhedrin promoter. A 66-kilodalton protein, identical in size to the glycosylated glycoprotein of infectious hematopoietic necrosis virus, was expressed at high levels in Spodoptera frugiperda cells infected with the recombinant viruses. The expressed protein reacted with antiserum to the glycoprotein on Western blots.

  15. Monensin and FCCP inhibit the intracellular transport of alphavirus membrane glycoproteins

    OpenAIRE

    Kaariainen, L; Hashimoto, K.; Saraste, J; Virtanen, I; Penttinen, K

    1980-01-01

    Temperature-sensitive mutants of semliki forest virus (SFV) and sindbis virus (SIN) were used to study the intracellular transport of virus membrane glycoproteins in infected chicken embryo fibroblasts. When antisera against purified glycoproteins and (125)I- labeled protein A from staphylococcus aureus were used only small amounts of virus glycoproteins were detected at the surface of SFV ts-1 and SIN Ts-10 infected cells incubated at the restrictive temperature (39 degrees C). When the muta...

  16. Comparison of osteogenic potentials of human rat BMP4 and BMP6 gene therapy using [E1-] and [E1-,E2b-] adenoviral vectors

    Directory of Open Access Journals (Sweden)

    Hongwei Li, Jin Zhong Li, Debra D. Pittman, Andy Amalfitano, Gerald R. Hankins, Gregory A. Helm

    2006-01-01

    Full Text Available Osteogenic potentials of some recombinant human bone morphogenetic protein (BMP first-generation adenoviral vectors (ADhBMPs are significantly limited in immunocompetent animals. It is unclear what role expression of viral proteins and foreign proteins transduced by adenoviral vectors play in the host immune response and in ectopic bone formation. In this study two sets of experiments were designed and performed. First, rat BMP6 cDNA were amplified, sequenced, and recombined in first-generation adenoviral vector (ADrBMP6. A comparison of human and rat BMP6 adenoviral vectors demonstrated identical osteogenic activities in both immunodeficient and immunocompetent rats. Second, the activities of recombinant human BMP6 in E1- (ADhBMP6 and [E1-,E2b-] ( [E1-,E2b-]ADGFP&hBMP6, and [E1-,E2b-]ADhBMP6 adenoviral vectors were compared in both in vitro and in vivo models. Similar activities of these two generations of BMP adenoviral vectors were found in all models. These results indicate that the amount of viral gene expression and the source of the BMP cDNA are not major factors in the interruption of osteogenic potentials of recombinant BMP6 adenoviral vectors in immunocompetent animals.

  17. Human liver estrone (E1), Estradiol (E2) and dehydroepiandrosterone (DHEA) sulfotransferases (STs): Comparison with thermostable (TS) and thermolabile (TL) phenol sulfotransferase (PST) activities

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, J.S.; Watson, R.W.G.; Weinshilboum, R.M. (Mayo Clinic/Mayo Foundation, Rochester, MN (United States))

    1991-03-11

    Sulfation plays an important role in the metabolism of E1, E2 and DHEA in humans. The relationship between the enzymes that catalyze the sulfation of E1, E2 and DHEA and TS and TL PST is unclear. The authors compared thermal stability, sensitivity to inhibition by 2,6-dichloro-4-nitrophenol (DCNP) and individual variation in the regulation of these steroid ST activities with those of TS PST and TL PST in the human liver. E2 ST and TS PST had very similar thermal stabilities. The thermal inactivation profile of E1 ST suggested that this activity might be related to both DHEA ST and TS PST. DCNP inhibition studies also showed similar profiles for E2 ST and TS PST, with a small resistant component for E2 ST. A multiphasic profile for DCNP inhibition of E1 ST activity was found. Finally, studies performed with human liver sample showed significant correlations between E2 ST and TS PST, E1 ST and DHEA ST, E2 St and E1 ST, and, to a lesser degree, between E1 ST and TS PST and E2 ST and DHEA ST. TL PST was not correlated significantly with any of the other activities. These results suggest that the sulfation of E2 in human liver is catalyzed predominantly by TS PST, although DHEA ST may also play a role. Their results also suggest that the sulfation of E1 is catalyzed by DHEA ST and by TS PST, although other ST(s) could also be involved.

  18. Inhibition of human immunodeficiency virus (HIV) infection in vitro by anticarbohydrate monoclonal antibodies: peripheral glycosylation of HIV envelope glycoprotein gp120 may be a target for virus neutralization

    DEFF Research Database (Denmark)

    Hansen, J E; Clausen, H; Nielsen, C

    1990-01-01

    Carbohydrate structures are often involved in the initial adhesion of pathogens to target cells. In the present study, a panel of anticarbohydrate monoclonal antibodies (MAbs) was tested for their ability to inhibit in vitro human immunodeficiency virus infectivity. MAbs against three different N...... carbohydrate structures expressed by the viral envelope glycoprotein gp120, indicating that glycans of the viral envelope are possible targets for immunotherapy or vaccine development or both....

  19. A design for clock data recovery circuit of E1%一种E1时钟数据恢复电路的设计

    Institute of Scientific and Technical Information of China (English)

    李鑫; 黄海生; 张斌; 惠楠

    2012-01-01

    针对E1数据的时钟数据恢复问题,设计一种基于小数分频且有环路滤波功能的数控振荡器(DigitallyControlled Oscillator,DCO),给出一种新的全数字锁相环(All Digital Phase-Locked Loop,ADPLL)实现方案,将数字环路滤波器(Digital Loop Filter,DLF)和DCO集成到一个模块,从而实现一种E1时钟数据恢复(Clock Data Re-covery,CDR)电路。经过对比可知,新方案比传统ADPLL实现方案的电路集成度更高。理论分析显示,新方案电路性能可靠。%For the problem of E1 clock data recovery, a kind of Digitally Controlled Oscillator (DCO), which has loop filtering function based on fractional frequency dividing, is presented. Then it gives a new kind of All Digital Phase-Locked Loop(ADPLL) implemention scheme. On the basis of this scheme, a kind of E1 Clock Data Reeovery(CDR) circuit is implemented. Com- pared with traditional ADPLL implemention scheme, the scheme presented integrates Digital Loop Filter (DLF) and DCO together, thus the integration of the circuit becomes higher. The mathematical analysis to the circuit performance proves that the design can reliably recover the data and clock from E1 data received.

  20. Identification and antigenicity of the major envelope glycoprotein of lymphadenopathy-associated virus

    Energy Technology Data Exchange (ETDEWEB)

    Montagnier, L.; Clavel, F.; Krust, B.; Chamaret, S.; Rey, F.; Barre-Sinoussi, F.; Chermann, J.C.

    1985-07-15

    The major envelope glycoprotein of the causative agent of Acquired Immune Deficiency Syndrome (AIDS) lymphadenopathy-associated virus (LAV) has been identified and characterized. The glycoprotein has an apparent molecular weight of 110,000-120,000 under denaturing conditions in polyacrylamide gel electrophoresis. Upon deglycosylation by a specific endoglycosydase, its size is reduced to 80,000. Cellular precursors of this glycoprotein have been detected with apparent molecular weight of 150,000 and 135,000. Nearly all AIDS and pre-AIDS patients have detectable antibodies against this viral glycoprotein.

  1. Analysis of lectin-bound glycoproteins in snake venom from the Elapidae and Viperidae families.

    Science.gov (United States)

    Nawarak, Jiraporn; Phutrakul, Suree; Chen, Shui-Tein

    2004-01-01

    This paper describes an efficient method of studying the glycoproteins found in snake venom. The glycosylation profiles of the Elapidae and Viperidae snake families were analyzed using FITC-labeled lectin glycoconjugates. The Con A-agarose affinity enrichment technique was used to fractionate glycoproteins from the N. naja kaouthia venom. The results revealed a large number of Con A binding glycoproteins, most of which have moderate to high molecular weights. To identify the proteins, the isolated glycoprotein fractions were subjected to two-dimensional electrophoresis and MALDI-TOF MS. Protein sequences were compared with published protein databases to determine for their biological functions.

  2. Long-Term Prostaglandin E1 Infusion for Newborns with Critical Congenital Heart Disease.

    Science.gov (United States)

    Aykanat, Alper; Yavuz, Taner; Özalkaya, Elif; Topçuoğlu, Sevilay; Ovalı, Fahri; Karatekin, Güner

    2016-01-01

    Prostaglandin E1 is crucial for keeping the patent ductus arteriosus in critical congenital heart disease for the survival and palliation of particularly prematurely born babies until a cardiosurgical intervention is available. In this study, the side effects of prostaglandin E1 in newborns with critical congenital heart disease and clinical outcomes were evaluated. Thirty-five newborns diagnosed with critical congenital heart disease were treated with prostaglandin E1 between January 2012 and September 2014 at our hospital. Patient charts were examined for prostaglandin E1 side effects (metabolic, gastric outlet obstruction, apnea), clinical status, and prognosis. Acquired data were analyzed in the SPSS 20.0 program. Patients with birth weight under 2500 g needed more days of prostaglandin E1 infusion than ones with birthweight over 2500 g (P = 0.016). The ratio of patients with birth weight under 2500 g who received prostaglandin E1 longer than 7 days was higher than the patients with birth weight over 2500 g (P = 0.02). Eighteen side effects were encountered in 11 of 35 patients (31%). Of these side effects, 1 patient had 4, 4 patients had 2, and 6 patients had only 1 side effect. Discontinuation of the therapy was never needed. Prostaglandin E1 is an accepted therapy modality for survival and outcome in critical congenital heart disease in particularly low-birth-weight babies until a surgical intervention is available. Side effects are not less encountered but are almost always manageable, and discontinuation is not needed.

  3. Candida albicans modulates host defense by biosynthesizing the pro-resolving mediator resolvin E1.

    Directory of Open Access Journals (Sweden)

    Eric J Haas-Stapleton

    Full Text Available Candida albicans is an opportunistic fungal pathogen of humans that resides commensally on epithelial surfaces, but can cause inflammation when pathogenic. Resolvins are a class of anti-inflammatory lipids derived from omega-3 polyunsaturated fatty acids (PUFA that attenuate neutrophil migration during the resolution phase of inflammation. In this report we demonstrate that C. albicans biosynthesizes resolvins that are chemically identical to those produced by human cells. In contrast to the trans-cellular biosynthesis of human Resolvin E1 (RvE1, RvE1 biosynthesis in C. albicans occurs in the absence of other cellular partners. C. albicans biosynthesis of RvE1 is sensitive to lipoxygenase and cytochrome P450 monoxygenase inhibitors. We show that 10nM RvE1 reduces neutrophil chemotaxis in response to IL-8; 1nM RvE1 enhanced phagocytosis of Candida by human neutrophils, as well as intracellular ROS generation and killing, while having no direct affect on neutrophil motility. In a mouse model of systemic candidiasis, RvE1 stimulated clearance of the fungus from circulating blood. These results reveal an inter-species chemical signaling system that modulates host immune functions and may play a role in balancing host carriage of commensal and pathogenic C. albicans.

  4. Recombinant modified vaccinia virus Ankara expressing glycoprotein E2 of Chikungunya virus protects AG129 mice against lethal challenge.

    Directory of Open Access Journals (Sweden)

    Petra van den Doel

    2014-09-01

    Full Text Available Chikungunya virus (CHIKV infection is characterized by rash, acute high fever, chills, headache, nausea, photophobia, vomiting, and severe polyarthralgia. There is evidence that arthralgia can persist for years and result in long-term discomfort. Neurologic disease with fatal outcome has been documented, although at low incidences. The CHIKV RNA genome encodes five structural proteins (C, E1, E2, E3 and 6K. The E1 spike protein drives the fusion process within the cytoplasm, while the E2 protein is believed to interact with cellular receptors and therefore most probably constitutes the target of neutralizing antibodies. We have constructed recombinant Modified Vaccinia Ankara (MVA expressing E3E2, 6KE1, or the entire CHIKV envelope polyprotein cassette E3E26KE1. MVA is an appropriate platform because of its demonstrated clinical safety and its suitability for expression of various heterologous proteins. After completing the immunization scheme, animals were challenged with CHIV-S27. Immunization of AG129 mice with MVAs expressing E2 or E3E26KE1 elicited neutralizing antibodies in all animals and provided 100% protection against lethal disease. In contrast, 75% of the animals immunized with 6KE1 were protected against lethal infection. In conclusion, MVA expressing the glycoprotein E2 of CHIKV represents as an immunogenic and effective candidate vaccine against CHIKV infections.

  5. Enterasys Networks delivers 10-Gigabit ethernet for the enterprise with new matrix E1 switching family

    CERN Multimedia

    2001-01-01

    Enterasys Networks Inc., today announced its new Matrix E1 family of 10-Gigabit and Gigabit Ethernet switches. The Matrix E1 Optical Access Switch (OAS) enables organizations to deliver applications at 10-Gb speeds across a single fibre optic pair. Jacques Altaber, deputy leader of IT at CERN said "High-bandwith solutions are essential to leveraging more computing power, so 10-Gb Ethernet is the next logical step for us...The Matrix E1 allows us to provide the networking support that our scientists need and gives us a certain future for bandwidth and computing expansion".

  6. Inactivation of cyclin E1 inhibits chemically induced hepatocarcinogenesis in mice

    OpenAIRE

    Moro, Nives

    2011-01-01

    E-type cyclins (CcnE) control the transition of quiescent cells into the cell cycle. Two E-type cyclins, CcnE1 and CcnE2 have been described. A variety of human cancers, including hepatocellular carcinoma (HCC), overexpress CcnE and this is frequently associated with reduced patient survival. The aim of the present study was to dissect the role of CcnE1 and CcnE2 for hepatocarcinogenesis induced by the carcinogen diethylnitrosamine (DEN) using CcnE1 and CcnE2 knockout mice. The central questi...

  7. Sensitive search for the temporal variation of the fine structure constant using radio-frequency E1 transitions in atomic dysprosium

    CERN Document Server

    Nguyen, A T; Lamoreaux, S K; Torgerson, J R

    2003-01-01

    It has been proposed that the radio-frequency electric-dipole (E1) transition between two nearly degenerate opposite-parity states in atomic dysprosium should be highly sensitive to possible temporal variation of the fine structure constant ($\\alpha$) [V. A. Dzuba, V. V. Flambaum, and J. K. Webb, Phys. Rev. A {\\bf 59}, 230 (1999)]. We discuss here an experimental realization of the proposed search, which involves monitoring the E1 transition frequency over a period of time using direct frequency counting techniques. We estimate that a statistical sensitivity of $|\\adota| \\sim 10^{-18}$/yr may be achieved and discuss possible systematic effects in such a measurement.

  8. P-Glycoprotein in skin contributes to transdermal absorption of topical corticosteroids.

    Science.gov (United States)

    Hashimoto, Naoto; Nakamichi, Noritaka; Yamazaki, Erina; Oikawa, Masashi; Masuo, Yusuke; Schinkel, Alfred H; Kato, Yukio

    2017-04-15

    ATP binding cassette transporters, P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), are expressed in skin, but their involvement in transdermal absorption of clinically used drugs remains unknown. Here, we examined their role in transdermal absorption of corticosteroids. Skin and plasma concentrations of dexamethasone after dermal application were reduced in P-gp and BCRP triple-knockout (Mdr1a/1b/Bcrp(-/-)) mice. The skin concentration in Mdr1a/1b/Bcrp(-/-) mice was reduced in the dermis, but not in the epidermis, indicating that functional expression of these transporters in skin is compartmentalized. Involvement of these transporters in dermal transport of dexamethasone was also supported by the observation of a higher epidermal concentration in Mdr1a/1b/Bcrp(-/-) than wild-type mice during intravenous infusion. Transdermal absorption after dermal application of prednisolone, but not methylprednisolone or ethinyl estradiol, was also lower in Mdr1a/1b/Bcrp(-/-) than in wild-type mice. Transport studies in epithelial cell lines transfected with P-gp or BCRP showed that dexamethasone and prednisolone are substrates of P-gp, but are minimally transported by BCRP. Thus, our findings suggest that P-gp is involved in transdermal absorption of at least some corticosteroids in vivo. P-gp might be available as a target for inhibition in order to deliver topically applied drugs and cosmetics in a manner that minimizes systemic exposure.

  9. Characterization of the Receptor-binding Domain of Ebola Glycoprotein in Viral Entry

    Institute of Scientific and Technical Information of China (English)

    Jizhen Wang; Balaji Manicassamy; Michael Caffrey; Lijun Rong

    2011-01-01

    Ebola virus infection causes severe hemorrhagic fever in human and non-human primates with high mortality.Viral entry/infection is initiated by binding of glycoprotein GP protein on Ebola virion to host cells,followed by fusion of virus-cell membrane also mediated by GP.Using an human immunodeficiency virus (HIV)-based pseudotyping system,the roles of 41 Ebola GP1 residues in the receptor-binding domain in viral entry were studied by alanine scanning substitutions.We identified that four residues appear to be involved in protein folding/structure and four residues are important for viral entry.An improved entry interference assay was developed and used to study the role of these residues that are important for viral entry.It was found that R64 and K95 are involved in receptor binding.In contrast,some residues such as I170 are important for viral entry,but do not play a major role in receptor binding as indicated by entry interference assay and/or protein binding data,suggesting that these residues are involved in post-binding steps of viral entry.Furthermore,our results also suggested that Ebola and Marburg viruses share a common cellular molecule for entry.

  10. HIV-1 gp120 envelope glycoprotein determinants for cytokine burst in human monocytes

    Science.gov (United States)

    Coutu, Mathieu; Prévost, Jérémie; Brassard, Nathalie; Peres, Adam; Stegen, Camille; Madrenas, Joaquín; Kaufmann, Daniel E.; Finzi, Andrés

    2017-01-01

    The first step of HIV infection involves the interaction of the gp120 envelope glycoprotein to its receptor CD4, mainly expressed on CD4+ T cells. Besides its role on HIV-1 entry, the gp120 has been shown to be involved in the production of IL-1, IL-6, CCL20 and other innate response cytokines by bystander, uninfected CD4+ T cells and monocytes. However, the gp120 determinants involved in these functions are not completely understood. Whether signalling leading to cytokine production is due to CD4 or other receptors is still unclear. Enhanced chemokine receptor binding and subsequent clustering receptors may lead to cytokine production. By using a comprehensive panel of gp120 mutants, here we show that CD4 binding is mandatory for cytokine outburst in monocytes. Our data suggest that targeting monocytes in HIV-infected patients might decrease systemic inflammation and the potential tissue injury associated with the production of inflammatory cytokines. Understanding how gp120 mediates a cytokine burst in monocytes might help develop new approaches to improve the chronic inflammation that persists in these patients despite effective suppression of viremia by antiretroviral therapy. PMID:28346521

  11. Reversion of P-Glycoprotein-Mediated Multidrug Resistance in Human Leukemic Cell Line by Diallyl Trisulfide

    Directory of Open Access Journals (Sweden)

    Qing Xia

    2012-01-01

    Full Text Available Multidrug resistance (MDR is the major obstacle in chemotherapy, which involves multiple signaling pathways. Diallyl trisulfide (DATS is the main sulfuric compound in garlic. In the present study, we aimed to explore whether DATS could overcome P-glycoprotein-(P-gp-mediated MDR in K562/A02 cells, and to investigate whether NF-κB suppression is involved in DATS-induced reversal of MDR. MTT assay revealed that cotreatment with DATS increased the response of K562/A02 cells to adriamycin (the resistance reversal fold was 3.79 without toxic side effects. DATS could enhance the intracellular concentration of adriamycin by inhibiting the function and expression of P-gp, as shown by flow cytometry, RT-PCR, and western blot. In addition, DATS resulted in more K562/A02 cell apoptosis, accompanied by increased expression of caspase-3. The expression of NF-κB/p65 (downregulation was significantly linked to the drug-resistance mechanism of DATS, whereas the expression of IκBα was not affected by DATS. Our findings demonstrated that DATS can serve as a novel, nontoxic modulator of MDR, and can reverse the MDR of K562/A02 cells in vitro by increasing intracellular adriamycin concentration and inducing apoptosis. More importantly, we proved for the first time that the suppression of NF-κB possibly involves the molecular mechanism in the course of reversion by DATS.

  12. The Plasmin-Sensitive Protein Pls in Methicillin-Resistant Staphylococcus aureus (MRSA) Is a Glycoprotein

    Science.gov (United States)

    Pohlentz, Gottfried; Xia, Guoqing; Hussain, Muzaffar; Foster, Simon; Peters, Georg

    2017-01-01

    Most bacterial glycoproteins identified to date are virulence factors of pathogenic bacteria, i.e. adhesins and invasins. However, the impact of protein glycosylation on the major human pathogen Staphylococcus aureus remains incompletely understood. To study protein glycosylation in staphylococci, we analyzed lysostaphin lysates of methicillin-resistant Staphylococcus aureus (MRSA) strains by SDS-PAGE and subsequent periodic acid-Schiff’s staining. We detected four (>300, ∼250, ∼165, and ∼120 kDa) and two (>300 and ∼175 kDa) glycosylated surface proteins with strain COL and strain 1061, respectively. The ∼250, ∼165, and ∼175 kDa proteins were identified as plasmin-sensitive protein (Pls) by mass spectrometry. Previously, Pls has been demonstrated to be a virulence factor in a mouse septic arthritis model. The pls gene is encoded by the staphylococcal cassette chromosome (SCC)mec type I in MRSA that also encodes the methicillin resistance-conferring mecA and further genes. In a search for glycosyltransferases, we identified two open reading frames encoded downstream of pls on the SCCmec element, which we termed gtfC and gtfD. Expression and deletion analysis revealed that both gtfC and gtfD mediate glycosylation of Pls. Additionally, the recently reported glycosyltransferases SdgA and SdgB are involved in Pls glycosylation. Glycosylation occurs at serine residues in the Pls SD-repeat region and modifying carbohydrates are N-acetylhexosaminyl residues. Functional characterization revealed that Pls can confer increased biofilm formation, which seems to involve two distinct mechanisms. The first mechanism depends on glycosylation of the SD-repeat region by GtfC/GtfD and probably also involves eDNA, while the second seems to be independent of glycosylation as well as eDNA and may involve the centrally located G5 domains. Other previously known Pls properties are not related to the sugar modifications. In conclusion, Pls is a glycoprotein and Pls glycosyl

  13. Quasispecies Sequence Analyses of Envelope Protein E1/E2 Coding Genes from four Chinese HCV Patients and Identification of a Novel Insertion Mutation of HCV%四份中国HCV阳性血清中包膜蛋白E1/E2准种基因的序列分析及新型插入突变的发现

    Institute of Scientific and Technical Information of China (English)

    李从力; 张玲; 鲁健; 刘晓明; 邓瑶; 王岳; 沈晓玲; 谭文杰

    2012-01-01

    为分析四份中国丙型肝炎病毒(HCV)阳性血清中包膜蛋白E1/E2基因的准种特征.本研究对从4份中国HCV阳性血清(1b亚型:274、366和383;2a亚型:283)中提取的HCV核酸,采用逆转录-聚合酶反应扩增编码全长E1/E2蛋白(191~764aa)的基因片段,随机挑取多个克隆测序.根据E1/E2基因核苷酸的序列与其他相关序列(来自于GenBank)构建亲缘性关系进化树,进行核苷酸与氨基酸同源性分析并对重要的基因位点进行分析.共获得阳性克隆序列43个(274株10个,283株12个,366株13个,383株8个),发现高变区HVR1、HVR2的基因异质性高,而其他抗体中和表位及跨膜区I、Ⅱ及N末端糖基化位点相对保守.并首次发现在HCV 2a亚型(283血清)中多个准种序列存在1 279nt(E1区,313aa)处单碱基插入优势基因突变,导致HCV包膜蛋白编码突变与中断(E2区,398aa).本研究对中国HCV代表株包膜蛋白E1/E2编码基因的准种多样性及一种新型插入突变进行了描述,可为进一步研究HCV免疫逃避与慢性化机制提供重要信息.%This paper investigated the envelope protein E1/E2 quasispecies genetic characterization of 4 HCV positive sera (Genotype 1b:274,366,383; Genotype 2a;283) in China. Nucleotide acid was extracted and glycoprotein E1/E2 (191~764aa) coding genes were obtained by RT-PCR, positive clones were randomly selected for sequencing. The phylogenetic relationships and the homology of nucleotide and amino acid were analyzed based on E1/E2 coding genes, and some vital functional regions of E1/E2 were characterized. A total of 43 sequences (274 : 10;283 : 12;366 : 13; 383 : 8) were obtained showing high genetic heterogeneity in HVR1 and HVR2 regions, while sequences of the neutralizing epitopes, transmembrane domain I,II and N-terminal ectodomain were comparatively conservative. Single base(C)insertion mutation at ntl279 ( El region, aa313),resulting in a mutated El coding protein (beginning at aa 313) and

  14. Monensin and FCCP inhibit the intracellular transport of alphavirus membrane glycoproteins.

    Science.gov (United States)

    Kääriäinen, L; Hashimoto, K; Saraste, J; Virtanen, I; Penttinen, K

    1980-12-01

    Temperature-sensitive mutants of semliki forest virus (SFV) and sindbis virus (SIN) were used to study the intracellular transport of virus membrane glycoproteins in infected chicken embryo fibroblasts. When antisera against purified glycoproteins and (125)I- labeled protein A from staphylococcus aureus were used only small amounts of virus glycoproteins were detected at the surface of SFV ts-1 and SIN Ts-10 infected cells incubated at the restrictive temperature (39 degrees C). When the mutant-infected cells were shifted to the permissive temperature (28 degrees C), in the presence of cycloheximide, increasing amounts of virus glycoproteins appeared at the cell surface from 20 to 80 min after the shift. Both monensin (10muM) and carbonylcyanide-p- trifluoromethoxyphenylhydrazone (FCCP; 10-20 muM) inhibited the appearance of virus membrane glycoproteins at the cell surface. Vinblastine sulfate (10 mug/ml) inhibited the transport by approximately 50 percent, whereas cytochalasin B (1 mug/ml) had only a marginal effect. Intracellular distribution of virus glycoproteins in the mutant-infected cells was visualized in double-fluorescence studies using lectins as markers for endoplasmic reticulum and Golgi apparatus. At 39 degrees C, the virus membrane glycoproteins were located at the endoplasmic reticulum, whereas after shift to 28 degrees C, a bright juxtanuclear reticular fluorescence was seen in the location of the Golgi apparatus. In the presence of monensin, the virus glycoproteins could migrate to the Golgi apparatus, although transport to the cell surface did not take place. When the shift was carried out in the presence of FCCP, negligible fluorescence was seen in the Golgi apparatus and the glycoproteins apparently remained in the rough endoplasmic reticulum. A rapid inhibition in the accumulation of virus glycoproteins at the cell surface was obtained when FCCP was added during the active transport period, whereas with monensin there was a delay of

  15. Acetato(N-[(E-1-(6-methyl-2-pyridylmethylidene]-2-{2-[(E-1-(6-methyl-2-pyridylmethylideneamino]phenethyl}anilinenickel(II perchlorate

    Directory of Open Access Journals (Sweden)

    Hong-In Lee

    2010-10-01

    Full Text Available In the title complex, [Ni(CH3COO(C28H26N4]ClO4, the NiII atom is coordinated by two imine N atoms and two pyridine N atoms of the N-[(E-1-(6-methyl-2-pyridylmethylidene]-2-(2-[(E-1-(6-methyl-2-pyridylmethylideneamino]phenethylaniline donor ligand and two O atoms of the acetate ion in a distorted octahedral coordination. The average Ni—N and Ni—O bond lengths are 2.131 (13 and 2.098 (11 Å, respectively. An intramolecular N—H...O interaction occurs. Relatively weak intermolecular C—H...O interactions between the ligands and the ClO4− ions result in a chain extending along the b axis.

  16. E1, M1, E2 transition energies and probabilities of W$^{54+}$ ions

    CERN Document Server

    Ding, Xiao-bin; Liu, Jia-xin; Koike, Fumihiro; Murakami, Izumi; Kato, Daiji; Sakaue, Hiroyuki A; Nakamura, Nobuyuki; Dong, Chen-zhong

    2016-01-01

    A comprehensive theoretical study of the E1, M1, E2 transitions of Ca-like tungsten ions is presented. Using multi-configuration Dirac-Fock (MCDF) method with a restricted active space treatment, the wavelengths and probabilities of the M1 and E2 transitions between the multiplets of the ground state configuration ([Ne]3s$^{2}$3p$^{6}$3d$^{2}$) and of the E1 transitions between [Ne]3s$^{2}$3p$^{5}$3d$^{3}$ and [Ne]3s$^{2}$3p$^{6}$3d$^{2}$ have been calculated. The results are in reasonable agreement with available experimental data. The present E1 and M1 calculations are compared with previous theoretical values. For E2 transitions, the importance of electron correlation from 3s and 3p orbitals is pointed out. Several strong E1 transitions are predicted, which have potential advantage for plasma diagnostics.

  17. 26 CFR 1.1397E-1 - Qualified zone academy bonds.

    Science.gov (United States)

    2010-04-01

    ... TAX (CONTINUED) INCOME TAXES Empowerment Zone Employment Credit § 1.1397E-1 Qualified zone academy...), (iii), (iv) or (v). Services of employees of the eligible local education agency do not constitute...

  18. 78 FR 15597 - Special Conditions: GE Aviation CT7-2E1 Turboshaft Engine Model

    Science.gov (United States)

    2013-03-12

    ... conditions are issued for the General Electric Aviation (GE) CT7-2E1 engine model. This engine model will... ensure the test will run for a 2.5 minute duration with no interruption. Type Certification Basis Under...

  19. Effects of E2 and E1-E2 Interference on Coulomb Dissociation of 19C

    Institute of Scientific and Technical Information of China (English)

    Rajesh Kharab; Pardeep Singh; Ravinder Kumar

    2007-01-01

    We investigate the effects of higher order multipole transitions, in particular electric quadrupole (E2) and E1-E2interference, on the Coulomb dissociation of 19 C within the framework of the first order eikonal approximation.The sensitivity of the total Coulomb breakup cross section and the longitudinal momentum distribution of the core fragment to these effects are checked. The breakup occurs predominately through the dipole transition and the contribution of E2 transition to the total cross section is found to be within the range from 1 to 3% of that of E1. It is further observed that the E1-E2 interference term contributes nothing to the integrated cross section.On the other hand, the longitudinal momentum distribution is observed to be insensitive to the E2 transition while the E1-E2 interference introduces a small asymmetry in its shape.

  20. The C-terminal region of E1A: a molecular tool for cellular cartography.

    Science.gov (United States)

    Yousef, Ahmed F; Fonseca, Gregory J; Cohen, Michael J; Mymryk, Joe S

    2012-04-01

    The adenovirus E1A proteins function via protein-protein interactions. By making many connections with the cellular protein network, individual modules of this virally encoded hub reprogram numerous aspects of cell function and behavior. Although many of these interactions have been thoroughly studied, those mediated by the C-terminal region of E1A are less well understood. This review focuses on how this region of E1A affects cell cycle progression, apoptosis, senescence, transformation, and conversion of cells to an epithelial state through interactions with CTBP1/2, DYRK1A/B, FOXK1/2, and importin-α. Furthermore, novel potential pathways that the C-terminus of E1A influences through these connections with the cellular interaction network are discussed.

  1. CYP2E1-catalyzed oxidation contributes to the sperm toxicity of 1-bromopropane in mice.

    Science.gov (United States)

    Garner, C Edwin; Sloan, C; Sumner, S C J; Burgess, J; Davis, J; Etheridge, A; Parham, A; Ghanayem, B I

    2007-03-01

    1-bromopropane (1-BrP) induces dose- and time-dependent reproductive organ toxicity and reduced sperm motility in rodents. The contribution of cytochrome P4502E1 (CYP2E1) to both 1-BrP metabolism and the induction of male reproductive toxicity was investigated using wild-type (WT) and Cyp2e1-/- mice. In gas uptake inhalation studies, the elimination half-life of [1,2,3-(13)C]-1-BrP was longer in Cyp2e1-/- mice relative to WT (3.2 vs. 1.3 h). Urinary metabolites were identified by 13C nuclear magnetic resonance. The mercapturic acid of 1-bromo-2-hydroxypropane (2OHBrP) was the major urinary metabolite in WT mice, and products of conjugation of 1-BrP with glutathione (GSH) were insignificant. The ratio of GSH conjugation to 2-hydroxylation increased 5-fold in Cyp2e1-/- mice relative to WT. After 1-BrP exposure, hepatic GSH was decreased by 76% in WT mice vs. 47% in Cyp2e1-/- mice. Despite a 170% increase in 1-BrP exposure in Cyp2e1-/- vs. WT mice, sperm motility in exposed Cyp2e1-/- mice did not change relative to unexposed matched controls. This suggests that metabolites produced through CYP2E1-mediated oxidation may be responsible for 1-BrP-induced sperm toxicity. Both 1-BrP and 2OHBrP inhibited the motility of sperm obtained from WT mice in vitro. However, only 2OHBrP reduced the motility of sperm obtained from Cyp2e1-/- mice in vitro, suggesting that conversion of parent compound to 2OHBrP within the spermatozoa may contribute, at least in part, to reduced motility. Overall, these data suggest that metabolism of 1-BrP is mediated in part by CYP2E1, and activation of 1BrP via this enzyme may contribute to the male reproductive toxicity of this chemical.

  2. Role of CYP2E1 gene polymorphisms association with hepatitis risk in Northeast India

    Institute of Scientific and Technical Information of China (English)

    Manab; Deka; Moumita; Bose; Bharati; Baruah; Purabi; Deka; Bose; Subhash; Medhi; Sujoy; Bose; Anjan; Saikia; Premashish; Kar

    2010-01-01

    AIM:To investigate hepatitis virus, genetic and environmental factors, and their interactions in predisposing patients to liver diseases in Northeast India. METHODS:A total of 104 jaundice patients and 124 community controls were included. Serological analysis was performed by routine enzyme-linked immunosorbent assay, and nucleic acid testing for hepatitis viruses was done by polymerase chain reaction (PCR), followed by PCR direct sequencing for viral genotyping. Cytochrome P450 2E1 (CYP2E1) polymorphism w...

  3. Cooperative effects for CYP2E1 differ between styrene and its metabolites

    OpenAIRE

    2013-01-01

    Cooperative interactions are frequently observed in the metabolism of drugs and pollutants by cytochrome P450s; nevertheless, the molecular determinants for cooperativity remain elusive. Previously, we demonstrated that steady-state styrene metabolism by CYP2E1 exhibits positive cooperativity.We hypothesized that styrene metabolites have lower affinity than styrene toward CYP2E1 and limited ability to induce cooperative effects during metabolism. To test the hypothesis, we determined the pote...

  4. Phenotypic diversity of toxigenic Vibrio cholerae O1 E1 Tor strains identified in China

    Institute of Scientific and Technical Information of China (English)

    赵璇

    2014-01-01

    Objective To understand the phenotypic diversity of toxigenic Vibrio cholerae O1 E1 Tor strains isolated from different provinces in China during the last 50 years.Methods Traditional biotyping testings including susceptibility to polymyxin B,sensitivity to groupⅣphage,Voges-Proskauer test and haemolysis of sheep erythrocytes were conducted.Results Data from Biotype-specific phenotype analysis revealed that only 133 isolates carried the typical E1 Tor phenotypes while the other 251

  5. Evolution of the ubiquitin-activating enzyme Uba1 (E1)

    Science.gov (United States)

    Allan, Douglas C.; Phillips, J. C.

    2017-10-01

    Ubiquitin tags diseased proteins and initiates an enzyme conjugation cascade, which has three stages. The first-stage enzyme Uba1 (E1) has evolved only modestly from slime mold to humans, and is > 14 times larger than Ub. Here we use critical point thermodynamic scaling theory to connect Uba1 (E1) evolution from yeast and slime mold to fruit flies and humans to subtle changes in its amino acid sequences.

  6. The effect of prostaglandin E_1 on recovery of early renal graft functions after transplantation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Objective To investigate the effect of prostaglandin E1 (PGE1) on recovery of early renal graft functions after transplantation. Methods One hundred and seven patients after renal transplantation were allocated in the treated group, and treated by conventional treatment with injection of 10 μg prostaglandin E1 additionally twice a day for 14 days. And eighty-eight patients who received conventional treatment alone after renal transplantation at the corresponding period were allocated in the control group. I...

  7. The Frequency of Cytochrome P450 2E1 Polymorphisms in Black South Africans

    Directory of Open Access Journals (Sweden)

    Paul K. Chelule

    2006-01-01

    Full Text Available Polymorphisms in the promoter region of the Cytochrome P4502E1 (CYP2E1 gene reportedly modify the metabolic activity of CYP2E1 enzyme, and have been associated with increased susceptibility to squamous cell carcinoma (SCC of the oesophagus in high prevalence areas such as China. To assess the frequency of these polymorphisms in Black South Africans, a population with a high incidence of oesophageal SCC, this study examined genomic DNA from 331 subjects for restriction fragment length polymorphisms in the CYP2E1 (RsaI and PstI digestion. The frequency of the CYP2E1 c1/c1 and c1/c3 genotypes was 95% and 5% respectively. The frequency of the CYP2E1 allele distribution was found to be markedly different between Chinese and South African populations; hence it is important to place racial differences into consideration when proposing allelic variants as genetic markers for cancer.

  8. In vitro characterization of the NAD+ synthetase NadE1 from Herbaspirillum seropedicae.

    Science.gov (United States)

    Laskoski, Kerly; Santos, Adrian R S; Bonatto, Ana C; Pedrosa, Fábio O; Souza, Emanuel M; Huergo, Luciano F

    2016-05-01

    Nicotinamide adenine dinucleotide synthetase enzyme (NadE) catalyzes the amination of nicotinic acid adenine dinucleotide (NaAD) to form NAD(+). This reaction represents the last step in the majority of the NAD(+) biosynthetic routes described to date. NadE enzymes typically use either glutamine or ammonium as amine nitrogen donor, and the reaction is energetically driven by ATP hydrolysis. Given the key role of NAD(+) in bacterial metabolism, NadE has attracted considerable interest as a potential target for the development of novel antibiotics. The plant-associative nitrogen-fixing bacteria Herbaspirillum seropedicae encodes two putative NadE, namely nadE1 and nadE2. The nadE1 gene is linked to glnB encoding the signal transduction protein GlnB. Here we report the purification and in vitro characterization of H. seropedicae NadE1. Gel filtration chromatography analysis suggests that NadE1 is an octamer. The NadE1 activity was assayed in vitro, and the Michaelis-Menten constants for substrates NaAD, ATP, glutamine and ammonium were determined. Enzyme kinetic and in vitro substrate competition assays indicate that H. seropedicae NadE1 uses glutamine as a preferential nitrogen donor.

  9. Structural analysis and evolution of specificity of the SUMO UFD E1-E2 interactions

    Science.gov (United States)

    Liu, Bing; Lois, L. Maria; Reverter, David

    2017-01-01

    SUMO belongs to the ubiquitin-like family (UbL) of protein modifiers. SUMO is conserved among eukaryotes and is essential for the regulation of processes such as DNA damage repair, transcription, DNA replication and mitosis. UbL modification of proteins occurs via a specific enzymatic cascade formed by the crosstalk between the E1-activating enzyme, the E2-conjugating enzyme and the E3-ligase. An essential discrimination step in all UbL modifiers corresponds to the interaction between E1 and E2 enzymes, which is mediated by the recruitment of the E2 to the UFD domain (Ubiquitin-Fold Domain) of the E1 enzyme. To gain insights in the properties of this interface, we have compared the structures of the complexes between E1 UFD domain and E2 in human and yeast, revealing two alternative UFD platforms that interact with a conserved E2. Comparative sequence analysis of the E1 UFD domain indicates that the E2 binding region has been conserved across phylogenetic closely related species, in which higher sequence conservation can be found in the E2 binding region than in the entire UFD domain. These distinctive strategies for E1-E2 interactions through the UFD domain might be the consequence of a high selective pressure to ensure specificity of each modifier conjugation system. PMID:28165030

  10. Synthesis and translocation of gangliosides and glycoproteins during urethane anesthesia

    Energy Technology Data Exchange (ETDEWEB)

    Domowicz, M.S.; Kivatinitz, S.C.; Caputto, B.L.; Caputto, R.

    1988-05-01

    In this work, we have studied (a) the contents of gangliosides, glycoproteins, and phospholipids of the vesicle and plasma membrane fractions from brains of anesthetized and control rats and chickens and (b) the labeling of gangliosides and glycoproteins in the retina ganglion cell layer and optic tectum of urethane-anesthetized and control chickens after intraocular injection of a labeled N-acetylneuraminic acid precursor and the distribution of the label after subcellular fractionation. We found an increase in the content of gangliosides relative to protein in the vesicle fraction of both anesthetized rats and chickens relative to their controls. Other values were not affected by anesthesia. These results do not reflect a faster synthesis of gangliosides stimulated by urethane, because their rate of labeling was diminished in anesthetized animals. During the 4-h period after the animals were injected intraocularly with the radioactive precursor, the highest values of ganglioside-specific radioactivity were found in the vesicle fraction of control and anesthetized animals; at longer intervals, the specific radioactivity of the vesicle and plasma membrane fractions became rather similar. These data are in accordance with previous studies from this laboratory suggesting that the synthesis of the carbohydrate chain of gangliosides is regulated by the physiological demands made by the neurotransmitting system.

  11. Interaction of native and asialo rat sublingual glycoproteins with lectins.

    Science.gov (United States)

    Wu, A M; Herp, A; Song, S C; Wu, J H; Chang, K S

    1995-01-01

    The binding properties of the rat sublingual glycoprotein (RSL) and its asialo product with lectins were characterized by quantitative precipitin(QPA) and precipitin inhibition(QPIA) assays. Among twenty lectins tested for QPA, native RSL reacted well only with Artocarpus integrifolia (jacalin), but weakly or not at all with the other lectins. However, its asialo product (asialo-RSL) reacted strongly with many Gal and GalNAc specific lectins-it bound best to three of the GalNAc alpha 1-->Ser/Thr (Tn) and/or Gal beta 1-->4GlcNAc (II) active lectins [jacalin, Wistaria floribunda and Ricinus communis agglutinins] and completely precipitated each of these three lectins. Asialo-RSL also reacted well with Abrus precatorius, Glycine max, Bauhinia purpurea alba, and Maclura pomifera agglutinins, and abrin-a, but not with Arachis hypogeae and Dolichos biflorus agglutinins. The interaction between asialo-RSL and lectins were inhibited by either Gal beta 1-->4GlcNAc, p-NO2-phenyl alpha-GalNAc or both. The mapping of the precipitation and inhibition profiles leads to the conclusion that the asialo rat sublingual glycoprotein provides important ligands for II (Gal beta 1-->4GlcNAc beta 1-->) and Tn (GalNAc alpha 1-->Ser/Thr) active lectins.

  12. Characterization of monomeric intermediates during VSV glycoprotein structural transition.

    Directory of Open Access Journals (Sweden)

    Aurélie A Albertini

    2012-02-01

    Full Text Available Entry of enveloped viruses requires fusion of viral and cellular membranes, driven by conformational changes of viral glycoproteins. Crystal structures provide static pictures of pre- and post-fusion conformations of these proteins but the transition pathway remains elusive. Here, using several biophysical techniques, including analytical ultracentrifugation, circular dichroïsm, electron microscopy and small angle X-ray scattering, we have characterized the low-pH-induced fusogenic structural transition of a soluble form of vesicular stomatitis virus (VSV glycoprotein G ectodomain (G(th, aa residues 1-422, the fragment that was previously crystallized. While the post-fusion trimer is the major species detected at low pH, the pre-fusion trimer is not detected in solution. Rather, at high pH, G(th is a flexible monomer that explores a large conformational space. The monomeric population exhibits a marked pH-dependence and adopts more elongated conformations when pH decreases. Furthermore, large relative movements of domains are detected in absence of significant secondary structure modification. Solution studies are complemented by electron micrographs of negatively stained viral particles in which monomeric ectodomains of G are observed at the viral surface at both pH 7.5 and pH 6.7. We propose that the monomers are intermediates during the conformational change and thus that VSV G trimers dissociate at the viral surface during the structural transition.

  13. Histochemical and structural analysis of mucous glycoprotein secreted by the gill of Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Hae-Young.

    1988-01-01

    Studies were carried out to characterized various mucous cells in the gill filament, to ascertain structural characteristics of the secreted mucous glycoproteins, and to determine the ability of the gill epithelium to incorporate ({sup 14}C)glucosamine as a precursor in the biosynthesis and secretion of mucous glycoproteins. Using histochemical staining techniques, mucous cells containing neutral and acidic mucins were found in the lateral region, whereas mucous cells containing primarily neutral or sulfated mucins were found in the postlateral region. Serotonin, but not dopamine, stimulated the mucous secretion. In tissues pretreated with ({sup 14}C)glucosamine, the secreted glycoproteins contain incorporated radiolabel. Analysis by column chromatography using Bio-Gel P-2 and P-6 shows that the secretion contains two glycoprotein populations. Glycoprotein II has a molecular weight of 2.3 {times} 10{sup 4} daltons. Upon alkaline reductive borohydride cleavage of the O-glycosidic linkages of glycoprotein I, about 70% of the radiolabel was removed from the protein. Gas chromatographic analysis of the carbohydrate composition shows that the glycoproteins contains N-acetylglucosamine (GluNAc), N-acetylgalactosamine (GalNAc), and galactose, fucose and mannose. Amino acid analysis shows that the glycoproteins are rich in serine, threonine and proline.

  14. Characterization of Lassa virus glycoprotein oligomerization and influence of cholesterol on virus replication.

    Science.gov (United States)

    Schlie, Katrin; Maisa, Anna; Lennartz, Frank; Ströher, Ute; Garten, Wolfgang; Strecker, Thomas

    2010-01-01

    Mature glycoprotein spikes are inserted in the Lassa virus envelope and consist of the distal subunit GP-1, the transmembrane-spanning subunit GP-2, and the signal peptide, which originate from the precursor glycoprotein pre-GP-C by proteolytic processing. In this study, we analyzed the oligomeric structure of the viral surface glycoprotein. Chemical cross-linking studies of mature glycoprotein spikes from purified virus revealed the formation of trimers. Interestingly, sucrose density gradient analysis of cellularly expressed glycoprotein showed that in contrast to trimeric mature glycoprotein complexes, the noncleaved glycoprotein forms monomers and oligomers spanning a wide size range, indicating that maturation cleavage of GP by the cellular subtilase SKI-1/S1P is critical for formation of the correct oligomeric state. To shed light on a potential relation between cholesterol and GP trimer stability, we performed cholesterol depletion experiments. Although depletion of cholesterol had no effect on trimerization of the glycoprotein spike complex, our studies revealed that the cholesterol content of the viral envelope is important for the infectivity of Lassa virus. Analyses of the distribution of viral proteins in cholesterol-rich detergent-resistant membrane areas showed that Lassa virus buds from membrane areas other than those responsible for impaired infectivity due to cholesterol depletion of lipid rafts. Thus, derivation of the viral envelope from cholesterol-rich membrane areas is not a prerequisite for the impact of cholesterol on virus infectivity.

  15. Structural analysis of N- and O-glycans released from glycoproteins

    DEFF Research Database (Denmark)

    Jensen, Pia Hønnerup; Karlsson, Niclas G; Kolarich, Daniel;

    2012-01-01

    This protocol shows how to obtain a detailed glycan compositional and structural profile from purified glycoproteins or protein mixtures, and it can be used to distinguish different isobaric glycan isomers. Glycoproteins are immobilized on PVDF membranes before the N-glycans are enzymatically...

  16. Filamentous fungi as production organisms for glycoproteins of bio-medical interest

    NARCIS (Netherlands)

    Maras, M.; Die, I. van; Contreras, R.; Hondel, C.A.M.J.J. van den

    1999-01-01

    Filamentous fungi are commonly used in the fermentation industry for large scale production of glycoproteins. Several of these proteins can be produced in concentrations up to 20-40 g per litre. The production of heterologous glycoproteins is at least one or two orders of magnitude lower but researc

  17. Investigating the biomarker potential of glycoproteins using comparative glycoprofiling - application to tissue inhibitor of metalloproteinases-1

    DEFF Research Database (Denmark)

    Thøgersen, Ida; Lademann, Ulrik Axel; Offenberg, Hanne Kjær;

    2008-01-01

    Cancer-induced alterations of protein glycosylations are well-known phenomena. Hence, the glycoprofile of certain glycoproteins can potentially be used as biomarkers for early diagnosis. However, there are a substantial number of candidates and the techniques for measuring their biomarker potential...... tool for biomarker investigation of low-abundant glycoproteins....

  18. 21 CFR 866.5420 - Alpha-1-glycoproteins immunological test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alpha-1-glycoproteins immunological test system. 866.5420 Section 866.5420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5420 Alpha-1-glycoproteins immunological...

  19. 21 CFR 866.5425 - Alpha-2-glycoproteins immunological test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alpha-2-glycoproteins immunological test system. 866.5425 Section 866.5425 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5425 Alpha-2-glycoproteins immunological...

  20. Filamentous fungi as production organisms for glycoproteins of bio-medical interest

    NARCIS (Netherlands)

    Maras, M.; Die, I. van; Contreras, R.; Hondel, C.A.M.J.J. van den

    1999-01-01

    Filamentous fungi are commonly used in the fermentation industry for large scale production of glycoproteins. Several of these proteins can be produced in concentrations up to 20-40 g per litre. The production of heterologous glycoproteins is at least one or two orders of magnitude lower but

  1. Surface Glycoproteins of Exosomes Shed by Myeloid-Derived Suppressor Cells Contribute to Function.

    Science.gov (United States)

    Chauhan, Sitara; Danielson, Steven; Clements, Virginia; Edwards, Nathan; Ostrand-Rosenberg, Suzanne; Fenselau, Catherine

    2017-01-06

    In this report, we use a proteomic strategy to identify glycoproteins on the surface of exosomes derived from myeloid-derived suppressor cells (MDSCs), and then test if selected glycoproteins contribute to exosome-mediated chemotaxis and migration of MDSCs. We report successful modification of a surface chemistry method for use with exosomes and identify 21 surface N-glycoproteins on exosomes released by mouse mammary carcinoma-induced MDSCs. These glycoprotein identities and functionalities are compared with 93 N-linked glycoproteins identified on the surface of the parental cells. As with the lysate proteomes examined previously, the exosome surface N-glycoproteins are primarily a subset of the glycoproteins on the surface of the suppressor cells that released them, with related functions and related potential as therapeutic targets. The "don't eat me" molecule CD47 and its binding partners thrombospondin-1 (TSP1) and signal regulatory protein α (SIRPα) were among the surface N-glycoproteins detected. Functional bioassays using antibodies to these three molecules demonstrated that CD47, TSP1, and to a lesser extent SIRPα facilitate exosome-mediated MDSC chemotaxis and migration.

  2. Glycoproteins from sugarcane plants regulate cell polarity of Ustilago scitaminea teliospores.

    Science.gov (United States)

    Millanes, Ana-María; Fontaniella, Blanca; Legaz, María-Estrella; Vicente, Carlos

    2005-03-01

    Saccharum officinarum, cv. Mayarí, is a variety of sugarcane resistant to smut disease caused by Ustilago scitaminea. Sugarcane naturally produces glycoproteins that accumulate in the parenchymatous cells of stalks. These glycoproteins contain a heterofructan as polysaccharide moiety. The concentration of these glycoproteins clearly increases after inoculation of sugarcane plants with smut teliospores, although major symptoms of disease are not observed. These glycoproteins induce homotypic adhesion and inhibit teliospore germination. When glycoproteins from healthy, non-inoculated plants are fractionated, they inhibit actin capping, which occurs before teliospore germination. However, inoculation of smut teliospores induce glycoprotein fractions that promote teliospore polarity and are different from those obtained from healthy plants. These fractions exhibit arginase activity, which is strongly enhanced in inoculated plants. Arginase from healthy plants binds to cell wall teliospores and it is completely desorpted by sucrose, but only 50% of arginase activity from inoculated plants is desorpted by the disaccharide. The data presented herein are consistent with a model of excess arginase entry into teliospores. Arginase synthesized by sugarcane plants as a response to the experimental infection would increase the synthesis of putrescine, which impedes polarization at concentration values higher than 0.05 mM. However, smut teliospores seem to be able to change the pattern of glycoprotein production by sugarcane, thereby promoting the synthesis of different glycoproteins that activate polarization after binding to their cell wall ligand.

  3. Autophagy Protects against CYP2E1/Chronic Ethanol-Induced Hepatotoxicity

    Directory of Open Access Journals (Sweden)

    Yongke Lu

    2015-10-01

    Full Text Available Autophagy is an intracellular pathway by which lysosomes degrade and recycle long-lived proteins and cellular organelles. The effects of ethanol on autophagy are complex but recent studies have shown that autophagy serves a protective function against ethanol-induced liver injury. Autophagy was found to also be protective against CYP2E1-dependent toxicity in vitro in HepG2 cells which express CYP2E1 and in vivo in an acute alcohol/CYPE1-dependent liver injury model. The goal of the current report was to extend the previous in vitro and acute in vivo experiments to a chronic ethanol model to evaluate whether autophagy is also protective against CYP2E1-dependent liver injury in a chronic ethanol-fed mouse model. Wild type (WT, CYP2E1 knockout (KO or CYP2E1 humanized transgenic knockin (KI, mice were fed an ethanol liquid diet or control dextrose diet for four weeks. In the last week, some mice received either saline or 3-methyladenine (3-MA, an inhibitor of autophagy, or rapamycin, which stimulates autophagy. Inhibition of autophagy by 3-MA potentiated the ethanol-induced increases in serum transaminase and triglyceride levels in the WT and KI mice but not KO mice, while rapamycin prevented the ethanol liver injury. Treatment with 3-MA enhanced the ethanol-induced fat accumulation in WT mice and caused necrosis in the KI mice; little or no effect was found in the ethanol-fed KO mice or any of the dextrose-fed mice. 3-MA treatment further lowered the ethanol-decrease in hepatic GSH levels and further increased formation of TBARS in WT and KI mice, whereas rapamycin blunted these effects of ethanol. Neither 3-MA nor rapamycin treatment affected CYP2E1 catalytic activity or content or the induction CYP2E1 by ethanol. The 3-MA treatment decreased levels of Beclin-1 and Atg 7 but increased levels of p62 in the ethanol-fed WT and KI mice whereas rapamycin had the opposite effects, validating inhibition and stimulation of autophagy, respectively. These

  4. Cytochrome p450 2E1 polymorphisms and the risk of gastric cardia cancer

    Institute of Scientific and Technical Information of China (English)

    Lin Cai; Zong-Li Zheng; Zuo-Feng Zhang

    2005-01-01

    AIM: Genetic polymorphisms of drug-metabolizing enzymes have recently been shown to affect susceptibility to chemical carcinogenesis. Cytochrome P450 2E1 (CYP2E1)enzyme catalyzes the metabolism of many procarcinogens,such as N-nitrosamines and related compounds. The gene coding for this enzyme is polymorphic and thus may play a role in gastric cardia cancer (GCC) etiology. In this hospital-based case-control study, we evaluate the relationship between genetic polymorphisms of CYP2E1and the risk of GCC.METHODS: The study subjects comprised 159 histologically confirmed GCC cases identified via hospital cancer registry and surgical records at five hospitals in Fuzhou, Fujian Province, China, between April and November 2001.Controls were 192 patients admitted to the same hospitals for nonmalignant conditions. The genotypes of CYP2E1were detected by a PCR-based RFLP assay. The odds ratios were estimated by logistic regression analyses and were adjusted for potential confounding factors.RESULTS: The distribution of three genotypes of CYP2E1in GCC cases and controls was significantly different (X2 = 16.04, P<0.01). The frequency of the CYP2E1 (c1/c1)genotype in GCC cases and controls was 60.4% and 40.1%,respectively. The CYP2E1 (c1/c1) genotype was associated with an increased risk for GCC (the adjusted (OR) was 2.37, 95% confidence interval (CI): 1.52-3.70). Subjects who carried the CYP2E 1 (c1/c1) genotype and were habitual smokers were at a significantly higher risk of developing GCC (OR = 4.68, 95%CI: 2.19-10.04) compared with those who had the CYP2E1 (c1/c2or c2/c2') genotype and did not smoke.CONCLUSION: These results suggest that the CYP2E 1genotype may influence individual susceptibility to development of GCC, and that the risk increases significantly in smokers.

  5. PprM is necessary for up-regulation of katE1, encoding the major catalase of Deinococcus radiodurans, under unstressed culture conditions.

    Science.gov (United States)

    Jeong, Sun-Wook; Seo, Ho Seong; Kim, Min-Kyu; Choi, Jong-Il; Lim, Heon-Man; Lim, Sangyong

    2016-06-01

    Deinococcus radiodurans is a poly-extremophilic organism, capable of tolerating a wide variety of different stresses, such as gamma/ultraviolet radiation, desiccation, and oxidative stress. PprM, a cold shock protein homolog, is involved in the radiation resistance of D. radiodurans, but its role in the oxidative stress response has not been investigated. In this study, we investigated the effect of pprM mutation on catalase gene expression. pprM disruption decreased the mRNA and protein levels of KatE1, which is the major catalase in D. radiodurans, under normal culture conditions. A pprM mutant strain (pprM MT) exhibited decreased catalase activity, and its resistance to hydrogen peroxide (H2O2) decreased accordingly compared with that of the wild-type strain. We confirmed that RecG helicase negatively regulates katE1 under normal culture conditions. Among katE1 transcriptional regulators, the positive regulator drRRA was not altered in pprM (-), while the negative regulators perR, dtxR, and recG were activated more than 2.5-fold in pprM MT. These findings suggest that PprM is necessary for KatE1 production under normal culture conditions by down-regulation of katE1 negative regulators.

  6. Protective effect of Cardiospermum halicacabum leaf extract on glycoprotein components on STZ-induced hyperglycemic rats

    Institute of Scientific and Technical Information of China (English)

    Chinnadurai Veeramani; Khalid S Al-Numair; Mohammed A Alsaif; Govindasamy Chandramohan; Nouf S Al-Numair; Kodukkur Viswanathan Pugalendi

    2012-01-01

    Objective: To investigate the protective role of Cardiospermum halicacabum (C. halicacabum) leaf extract on glycoprotein metabolism in streptozotocin (STZ)-induced diabetic rats. Methods:Diabetes was induced in male albino Wistar rats by intraperitonial administration of STZ. TheC. halicacabum leaf extract (CHE) was administered orally to normal and STZ-diabetic rats for 45 days. The effects of C. halicacabum leaf extract (CHE) on plasma and tissue glycoproteins (hexose, hexosamine, fucose and sialic acid) were determined. Results: The levels of plasma and tissues glycoproteins containing hexose, hexosamine and fucose were significantly increased in STZ-induced diabetic rats. In addition, the level of sialic acid significantly increased in plasma and liver while decreased in kidney of STZ-induced diabetic rats. After administration of CHE to diabetic rats, the metabolic alteration of glycoprotein reverted towards normal levels.Conclusions:The present study indicates that the CHE possesses a protective effect on abnormal glycoprotein metabolism in addition to its antihyperglycemic activity.

  7. Novel thermo-responsive fucose binding ligands for glycoprotein purification by affinity precipitation.

    Science.gov (United States)

    Arnold, Lindsay; Chen, Rachel

    2014-02-01

    Novel thermo-responsive affinity sugar binders were developed by fusing a bacterial fucose lectin with a thermo-responsive polypeptide. These designer affinity ligand fusions were produced using an Escherichia coli system capable of extracellular secretion of recombinant proteins and were isolated with a high recovery yield (95%) directly from growth medium by Inverse Temperature Cycling (ITC). With horse radish peroxidase (HRP) as a model protein, we demonstrate here that the designer thermo-responsive ligands are capable of interacting with glycans on a glycoprotein, a property that was used to develop a novel affinity precipitation method for glycoprotein purification. The method, requiring only simple process steps, affords full recovery of a target glycoprotein, and is effective at a target glycoprotein concentration as low as 1.4 pM in the presence of large amounts of contaminants. By developing other sugar binders in the similar fashion, the method should be highly useful for glycoprotein purification and detection.

  8. Loop-acting diuretics do not bind to Tamm-Horsfall urinary glycoprotein.

    Science.gov (United States)

    Brunisholz, M C; Lynn, K L; Hunt, J S

    1987-09-01

    1. Binding between the radiolabelled loop-acting diuretics ([14C]frusemide, [14C]ethacrynic acid and [3H]bumetanide) and human Tamm-Horsfall glycoprotein or human serum albumin in vitro was evaluated by equilibrium dialysis. 2. The diuretic action and binding to urinary Tamm-Horsfall glycoprotein of the radiolabelled diuretics in vivo, after intravenous administration, were examined in rabbits. 3. In vitro, all three radiolabelled diuretics bound strongly to human serum albumin, but not to Tamm-Horsfall glycoprotein. 4. Radiolabelled frusemide and bumetanide, but not ethacrynic acid, caused a diuresis in rabbits, but no binding between the drugs and Tamm-Horsfall glycoprotein was seen in vivo. 5. Binding to Tamm-Horsfall glycoprotein does not appear to be an important mechanism in the action of loop diuretics.

  9. Glycoproteins of mouse vaginal epithelium: differential expression related to estrous cyclicity

    DEFF Research Database (Denmark)

    Horvat, B; Multhaupt, H A; Damjanov, I

    1993-01-01

    We used lectin overlay blotting and SDS-PAGE to analyze the estrous cycle-specific expression of mouse vaginal epithelial glycoproteins. Seven lectins chosen for their differential carbohydrate-binding specificity revealed 15 glycoproteins that showed cycle-related expression. Each lectin had...... a unique binding pattern different from the patterns revealed by other lectins. However, several estrous cycle phase-specific glycoproteins reacted with more than one lectin. The most prominent of these glycoproteins (M(r) 92-95 KD) was weakly expressed in late diestrus and fully expressed only...... in proestrus, coincident with the transformation of two superficial layers of vaginal squamous epithelium into mucinous cuboidal cells. Electron microscopic lectin histochemistry revealed the glycoproteins in the mucinous granules of surface cuboidal cells and in the lumen of the vagina. Our results illustrate...

  10. Demethoxycurcumin modulates human P-glycoprotein function via uncompetitive inhibition of ATPase hydrolysis activity.

    Science.gov (United States)

    Teng, Yu-Ning; Hsieh, Yow-Wen; Hung, Chin-Chuan; Lin, Hui-Yi

    2015-01-28

    Curcuminoids are major components of Curcuma longa L., which is widely used as spice in food. This study aimed at identifying whether curcumin, demethoxycurcumin, and bisdemethoxycurcumin could modulate efflux function of human P-glycoprotein and be used as chemosensitizers in cancer treatments. Without altering P-glycoprotein expression levels and conformation, the purified curcuminoids significantly inhibited P-glycoprotein efflux function. In rhodamine 123 efflux and calcein-AM accumulation assays, demethoxycurcumin demonstrated the highest inhibition potency (inhibitory IC50 = 1.56 ± 0.13 μM) among the purified curcuminoids, as well as in the fold of reversal assays. Demethoxycurcumin inhibited P-glycoprotein-mediated ATP hydrolysis under concentrations of P-glycoprotein. These results suggested that demethoxycurcumin may be a potential additive natural product in combination with chemotherapeutic agents in drug-resistant cancers.

  11. Developmental and mutational changes of glycoproteins in the mouse neuronal retina: studies with bovine galactosyltransferase.

    Science.gov (United States)

    Wallenfels, B

    1979-07-01

    Bovine galactosyltransferase (lactose synthase; EC 2.4.1.22) which catalyzes the transfer of galactose from UDPgalactose to glycoproteins with N-acetylglucosamine as the terminal residue of their oligosaccharide side chains was used to label glycoproteins of mouse retina with [14C]galactose. The glycoproteins were separated by isoelectric focusing in the first dimension and by sodium dodecyl sulfate gel electrophoresis in the second dimension. Their position on the gel was determined by autofluorography. With this method, quantitative as well as qualitative changes in the glycoprotein composition of the neuronal mouse retina during postnatal development were observed. Furthermore, it was found that the photoreceptor loss in mice with retinal degeneration was paralleled by the disappearance of certain glycoprotein bands.

  12. Production of Highly Sialylated Recombinant Glycoproteins Using Ricinus communis Agglutinin-I-Resistant CHO Glycosylation Mutants.

    Science.gov (United States)

    Goh, John S Y; Chan, Kah Fai; Song, Zhiwei

    2015-01-01

    The degree of sialylation of therapeutic glycoproteins affects its circulatory half-life and efficacy because incompletely sialylated glycoproteins are cleared from circulation by asialoglycoprotein receptors present in the liver cells. Mammalian expression systems, often employed in the production of these glycoprotein drugs, produce heterogeneously sialylated products. Here, we describe how to produce highly sialylated glycoproteins using a Chinese hamster ovary (CHO) cell glycosylation mutant called CHO-gmt4 with human erythropoietin (EPO) as a model glycoprotein. The protocol describes how to isolate and characterize the CHO glycosylation mutants and how to assess the sialylation of the recombinant protein using isoelectric focusing (IEF). It further describes how to inactivate the dihydrofolate reductase (DHFR) gene in these cells using zinc finger nuclease (ZFN) technology to enable gene amplification and the generation of stable cell lines producing highly sialylated EPO.

  13. Binding of soluble glycoproteins from sugarcane juice to cells of Acetobacter diazotrophicus.

    Science.gov (United States)

    Legaz, M E; de Armas, R; Barriguete, E; Vicente, C

    2000-09-01

    Sugarcane produces two different pools of glycoproteins containing a heterofructan as glycidic moiety, tentatively defined as high-molecular mass (HMMG) and mid-molecular mass (MMMG) glycoproteins. Both kinds of glycoproteins can be recovered in sugarcane juice. Fluorescein-labelled glycoproteins are able to bind to Acetobacter diazotrophicus cells, a natural endophyte of sugarcane. This property implies the aggregation of bacterial cells in liquid culture after addition of HMMG or MMMG. Anionic glycoproteins seem to be responsible for the binding activity whereas cationic fraction is not retained on the surface ofA. diazotrophicus. Bound HMMG is competitively desorbed by sucrose whereas MMMG is desorbed by glucosamine or fructose. On this basis, a hypothesis about the discriminatory ability of sugarcane to choose the compatible endophyte from several possible ones is proposed.

  14. Full-length core sequence dependent complex-type glycosylation of hepatitis C virus E2 glycoprotein

    Institute of Scientific and Technical Information of China (English)

    Li-Xin Zhu; Jing Liu; Ying-Chun Li; Yu-Ying Kong; Caroline Staib; Gerd Sutter; Yuan Wang; Guang-Di Li

    2002-01-01

    AIM: To study HCV polyprotein processing is important forthe understanding of the natural history of HCV and thedesign of vaccines against HCV. The purpose of this studyis to investigate the affection of context sequences onhepatitis C virus (HCV) E2 processingMETHODS: HCV genes of different lengths were expressedand compared in vaccinia virus/T7 system with homologouspatient serum S94 and mouse anti-serum ME2116 raisedagainst E. coli-derived E2 peptide, respectively.Deglycosylation analysis and GNA (Galanthus nivalus )lectin binding assay were performed to study the post-translational processing of the expressed products.RESULTS: E2 glycoproteins with different molecular weights( ~ 75kDa end ~ 60kDa) were detected using S94 and ME2116,respectively. Deglycosylation analysis showed that thisdifference was mainly due to different glycosylation. Endo Hresistance and its failure to bind to GNA lectin demonstratedthat the higher molecular weight form (75kDa) of E2 wascomplex-type glycosylated, which was readily recognized byhomologous patient serum S94. Expression of complex-typeglycosylated E2 could not be detected in all of the core-truncated constructs tested, but readily detected inconstructs encoding full-length core sequences.CONCLUSION: The upstream conserved full-length corecoding sequence was required for the production of E2glycoproteins carrying complex-type N-glycans whichreacted strongly with homologous patient serum andtherefore possibly represented more mature forms of E2. Ascomplex-type N-glycans indicated modification by Golgienzymes, the results suggest that the presence of full-lengthcore might be critical for E1/E2 complex to leave ER. Ourdata may contribute to a better understanding of theprocessing of HCV structural proteins as well as HCVmorphogenesis.

  15. Expression of Estrogen Sulfotransferase 1E1 and Steroid Sulfatase in Breast Cancer: A Immunohistochemical Study

    Directory of Open Access Journals (Sweden)

    D. Poisson Paré

    2009-01-01

    Full Text Available It is known that the steroid sulfatase (STS and the estrogen sulfotransferase (EST1E1 are commonly expressed in human breast carcinomas. STS and EST1E1 combined action could maintain the equilibrium between sulfated (inactive and unconjugated (active estrogens, which might have effects on development of hormone dependent breast cancer. We studied the expression of the STS and EST1E1 in 88 breast carcinomas and 57 adjacent non-malignant tissues by immunohistochemistry. The results were correlated with the tumor expression of estrogen receptor α (ER-α and β (ER-β, progesterone receptor A (PR-A and B (PR-B and the proliferation marker CDC47, the tumoral type and stage and the age at surgery. STS expression was higher in carcinoma specimens than in adjacent normal tissues, although not to a significant level (p = 0.064 and it was positively associated with CDC47 expression (p 0.05. These observations support the hypothesis that STS is overexpressed in breast cancer and associated with a worse prognosis. EST1E1 was observed for the first time in the nuclei of epithelial and tumoral cells. Tumor expression of EST1E1 was positively correlated with ER-β (p 0.01 and PR-B (p 0.05, two steroid receptors already associated with an improve prognosis for breast cancer. Controlling the STS overexpression in carcinomas could be a way to inhibit cancer growth. The significance of the association between EST1E1 and ER-β or PR-B should be further studied since these two receptors are transcription activators and may regulate the expression of protective enzymes like EST1E1.

  16. Cytochrome P450-2E1 promotes fast food-mediated hepatic fibrosis

    Science.gov (United States)

    Abdelmegeed, Mohamed A.; Choi, Youngshim; Godlewski, Grzegorz; Ha, Seung-Kwon; Banerjee, Atrayee; Jang, Sehwan; Song, Byoung-Joon

    2017-01-01

    Cytochrome P450-2E1 (CYP2E1) increases oxidative stress. High hepatic cholesterol causes non-alcoholic steatohepatitis (NASH) and fibrosis. Thus, we aimed to study the role of CYP2E1 in promoting liver fibrosis by high cholesterol-containing fast-food (FF). Male wild-type (WT) and Cyp2e1-null mice were fed standard chow or FF for 2, 12, and 24 weeks. Various parameters of liver fibrosis and potential mechanisms such as oxidative and endoplasmic reticulum (ER) stress, inflammation, and insulin resistance (IR) were studied. Indirect calorimetry was also used to determine metabolic parameters. Liver histology showed that only WT fed FF (WT-FF) developed NASH and fibrosis. Hepatic levels of fibrosis protein markers were significantly increased in WT-FF. The nitroxidative stress marker iNOS, but not CYP2E1, was significantly elevated only in FF-fed WT. Serum endotoxin, TLR-4 levels, and inflammatory markers were highest in WT-FF. FAS, PPAR-α, PPAR-γ, and CB1-R were markedly altered in WT-FF. Electron microscopy and immunoblot analyses showed significantly higher levels of ER stress in FF-fed WT. Indirect calorimetry showed that Cyp2e1-null-mice fed FF exhibited consistently higher total energy expenditure (TEE) than their corresponding WT. These results demonstrate that CYP2E1 is important in fast food-mediated liver fibrosis by promoting nitroxidative and ER stress, endotoxemia, inflammation, IR, and low TEE. PMID:28051126

  17. Neutrophil Resolvin E1 Receptor Expression and Function in Type 2 Diabetes.

    Science.gov (United States)

    Freire, Marcelo O; Dalli, Jesmond; Serhan, Charles N; Van Dyke, Thomas E

    2017-01-15

    Unresolved inflammation is key in linking metabolic dysregulation and the immune system in type 2 diabetes. Successful regulation of acute inflammation requires biosynthesis of specialized proresolving lipid mediators, such as E-series resolvin (RvE) 1, and activation of cognate G protein-coupled receptors. RvE1 binds to leukotriene B4 (BLT-1) on neutrophils and to ERV-1/ChemR23 on monocyte/macrophages. We show novel actions of RvE1 and expression patterns of neutrophil receptors in type 2 diabetes. Neutrophils from healthy subjects express functional BLT-1, low levels of minimally functional ERV-1, and inversed coexpression when compared to neutrophils from type 2 diabetes subjects. Stimulation with TNF-α or LPS increased the expression of ERV-1 by healthy and diabetic neutrophils. RvE1 counteracted LPS and TNF-α induction of ERV-1 overexpression and endogenous diabetic overexpression, activating phagocytosis and resolution signals. Functional ERV-1 was determined by phosphorylation of the signaling protein ribosomal S6. Receptor-antagonism experiments revealed that the increase in phosphorylation of ribosomal S6 was mediated by BLT-1 in healthy subject neutrophils and by ERV-1 in diabetes. Metabololipidomics reveal a proinflammatory profile in diabetic serum. Cell phagocytosis is impaired in type 2 diabetes and requires RvE1 for activation. The dose of RvE1 required to activate resolution signals in type 2 diabetic neutrophils was significantly higher than in healthy controls. RvE1 rescues the dysregulation seen on neutrophil receptor profile and, following a therapeutic dosage, activates phagocytosis and resolution signals in type 2 diabetes. These findings reveal the importance of resolution receptors in health, disease, and dysregulation of inflammation in type 2 diabetes.

  18. Sulfation of fulvestrant by human liver cytosols and recombinant SULT1A1 and SULT1E1

    Directory of Open Access Journals (Sweden)

    Edavana VK

    2011-11-01

    Full Text Available Vineetha Koroth Edavana1, Xinfeng Yu1, Ishwori B Dhakal1, Suzanne Williams1, Baitang Ning2, Ian T Cook3, David Caldwell1, Charles N Falany3, Susan Kadlubar11Division of Medical Genetics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA; 2Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR, USA; 3Department of Pharmacology, University of Alabama, Birmingham, AL, USAAbstract: Fulvestrant (Faslodex™ is a pure antiestrogen that is approved to treat hormone receptor-positive metastatic breast cancer in postmenopausal women. Previous studies have demonstrated that fulvestrant metabolism in humans involves cytochromes P450 and UDP-glucuronosyltransferases (UGTs. To date, fulvestrant sulfation has not been characterized. This study examined fulvestrant sulfation with nine recombinant sulfotransferases and found that only SULT1A1 and SULT1E1 displayed catalytic activity toward this substrate, with Km of 4.2 ± 0.99 and 0.2 ± 0.16 µM, respectively. In vitro assays of 104 human liver cytosols revealed marked individual variability that was highly correlated with β-naphthol sulfation (SULT1A1 diagnostic substrate; r = 0.98, P < 0.0001, but not with 17ß-estradiol sulfation (SULT1E1 diagnostic substrate; r = 0.16, P = 0.10. Fulvestrant sulfation was correlated with both SULT1A1*1/2 genotype (P value = 0.023 and copy number (P < 0.0001. These studies suggest that factors influencing SULT1A1/1E1 tissue expression and/or enzymatic activity could influence the efficacy of fulvestrant therapy.Keywords: fulvestrant, sulfotransferase, genotype, copy number

  19. Effect of reduced renal mass on renal ammonia transporter family, Rh C glycoprotein and Rh B glycoprotein, expression.

    Science.gov (United States)

    Kim, Hye-Young; Baylis, Chris; Verlander, Jill W; Han, Ki-Hwan; Reungjui, Sirirat; Handlogten, Mary E; Weiner, I David

    2007-10-01

    Kidneys can maintain acid-base homeostasis, despite reduced renal mass, through adaptive changes in net acid excretion, of which ammonia excretion is the predominant component. The present study examines whether these adaptations are associated with changes in the ammonia transporter family members, Rh B glycoprotein (Rhbg) and Rh C glycoprotein (Rhcg). We used normal Sprague-Dawley rats and a 5/6 ablation-infarction model of reduced renal mass; control rats underwent sham operation. After 1 wk, glomerular filtration rate, assessed as creatinine clearance, was decreased, serum bicarbonate was slightly increased, and Na(+) and K(+) were unchanged. Total urinary ammonia excretion was unchanged, but urinary ammonia adjusted for creatinine clearance, an index of per nephron ammonia metabolism, increased significantly. Although reduced renal mass did not alter total Rhcg protein expression, both light microscopy and immunohistochemistry with quantitative morphometric analysis demonstrated hypertrophy of both intercalated cells and principal cells in the cortical and outer medullary collecting duct that was associated with increased apical and basolateral Rhcg polarization. Rhbg expression, analyzed using immunoblot analysis, immunohistochemistry, and measurement of cell-specific expression, was unchanged. We conclude that altered subcellular localization of Rhcg contributes to adaptive changes in single-nephron ammonia metabolism and maintenance of acid-base homeostasis in response to reduced renal mass.

  20. P-glycoprotein levels predict poor outcome in patients with osteosarcoma.

    Science.gov (United States)

    Hornicek, F J; Gebhardt, M C; Wolfe, M W; Kharrazi, F D; Takeshita, H; Parekh, S G; Zurakowski, D; Mankin, H J

    2000-04-01

    To evaluate the relationship between the expression of P-glycoprotein by osteosarcomas and the rate of metastasis and death, a retrospective review of 172 patients who were diagnosed with osteosarcoma between 1987 and 1992 was performed. Forty patients had P-glycoprotein levels available. The majority of the osteosarcomas were Stage II-B (33 patients), with the remaining seven being Stage III. Tumor sites included 25 femurs, seven humeri, five tibias, and one each of pelvis, radius, and fibula. The patients with Stage III disease at presentation were treated differently from the time of diagnosis and therefore, these seven patients with Stage III osteosarcoma were excluded from additional analyses. The expression of P-glycoprotein by cultured tumor cells from biopsy specimens was determined using immunofluorescent microscopy. In the 33 patients with Stage IIB osteosarcoma with detectable P-glycoprotein, 67% (10 of 15) had metastases develop as compared with 28% (five of 18) of patients with undetectable P-glycoprotein. Similarly, 53% (eight of 15) of patients with tumors expressing P-glycoprotein died of disease compared with 11% (two of 18) with no detectable P-glycoprotein. Expression of P-glycoprotein by tumor cells seems to be associated with an estimated ninefold increase in the odds of death and a fivefold increase in the odds of metastases in patients with Stage IIB osteosarcoma. Kaplan-Meier survivorship analysis revealed that patients with detectable P-glycoprotein fared worse in terms of survival time and metastasis-free survival. Adjusting for covariates in the Cox proportional hazards model, expression of P-glycoprotein and its level were significantly predictive of time to death in patients with Stage IIB osteosarcoma.

  1. The Mechanism of Henipavirus Fusion: Examining the Relationships between the Attachment and Fusion Glycoproteins

    Institute of Scientific and Technical Information of China (English)

    Andrew C. Hickey; Christopher C. Broder

    2009-01-01

    The henipaviruses, represented by Nipah virus and Hendra virus, are emerging zoonotic viral pathogens responsible for repeated outbreaks associated with high morbidity and mortality in Australia, Southeast Asia, India and Bangladesh. These viruses enter host cells via a class I viral fusion mechanism mediated by their attachment and fusion envelope glycoproteins; efficient membrane fusion requires both these glycoproteins in conjunction with specific virus receptors present on susceptible host cells. The henipavirus attachment glycoprotein interacts with a cellular B class ephrin protein receptor triggering conformational alterations leading to the activation of the viral fusion (F) glycoprotein. The analysis of monoclonal antibody (mAb) reactivity with G has revealed measurable alterations in the antigenic structure of the glycoprotein following its binding interaction with receptor. These observations only appear to occur with full-length native G glycoprotein, which is a tetrameric oligomer, and not with soluble forms of G (sG), which are disulfide-linked dimers. Single amino acid mutations in a heptad repeat-like structure within the stalk domain of G can disrupt its association with F and subsequent membrane fusion promotion activity. Notably, these mutants of G also appear to confer a postreceptor bound conformation implicating the stalk domain as an important element in the G glycoprotein's structure and functional relationship with F. Together, these observations suggest fusion is dependent on a specific interaction between the F and G glycoproteins of the henipaviruses. Further, receptor binding induces measurable changes in the G glycoprotein that appear to be greatest in respect to the interactions between the pairs of dimers comprising its native tetrameric structure. These receptor-induced conformational changes may be associated with the G glycoprotein's promotion of the fusion activity of F.

  2. Appearance and cellular distribution of lectin-like receptors for alpha 1-acid glycoprotein in the developing rat testis

    DEFF Research Database (Denmark)

    Andersen, U O; Bøg-Hansen, T C; Kirkeby, S

    1996-01-01

    glycoprotein glycoforms to their receptors is inhibited by steroids. Testosterone, oestradiol and progesterone inhibited the binding of alpha 1-acid glycoprotein glycoform A to its receptor. Cortisone, aldosterone, oestradiol and progesterone inhibited the binding of alpha 1-acid glycoprotein glycoforms B...

  3. β2-Glycoprotein I/HLA class II complexes are novel autoantigens in antiphospholipid syndrome.

    Science.gov (United States)

    Tanimura, Kenji; Jin, Hui; Suenaga, Tadahiro; Morikami, Satoko; Arase, Noriko; Kishida, Kazuki; Hirayasu, Kouyuki; Kohyama, Masako; Ebina, Yasuhiko; Yasuda, Shinsuke; Horita, Tetsuya; Takasugi, Kiyoshi; Ohmura, Koichiro; Yamamoto, Ken; Katayama, Ichiro; Sasazuki, Takehiko; Lanier, Lewis L; Atsumi, Tatsuya; Yamada, Hideto; Arase, Hisashi

    2015-04-30

    Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by thrombosis and/or pregnancy complications. β2-glycoprotein I (β2GPI) complexed with phospholipid is recognized as a major target for autoantibodies in APS; however, less than half the patients with clinical manifestations of APS possess autoantibodies against the complexes. Therefore, the range of autoantigens involved in APS remains unclear. Recently, we found that human leukocyte antigen (HLA) class II molecules transport misfolded cellular proteins to the cell surface via association with their peptide-binding grooves. Furthermore, immunoglobulin G heavy chain/HLA class II complexes were specific targets for autoantibodies in rheumatoid arthritis. Here, we demonstrate that intact β2GPI, not peptide, forms a complex with HLA class II molecules. Strikingly, 100 (83.3%) of the 120 APS patients analyzed, including those whose antiphospholipid antibody titers were within normal range, possessed autoantibodies that recognize β2GPI/HLA class II complexes in the absence of phospholipids. In situ association between β2GPI and HLA class II was observed in placental tissues of APS patients but not in healthy controls. Furthermore, autoantibodies against β2GPI/HLA class II complexes mediated complement-dependent cytotoxicity against cells expressing the complexes. These data suggest that β2GPI/HLA class II complexes are a target in APS that might be involved in the pathogenesis.

  4. The human P-glycoprotein transporter enhances the type I interferon response to Listeria monocytogenes infection.

    Science.gov (United States)

    Sigal, Nadejda; Kaplan Zeevi, Millie; Weinstein, Shiri; Peer, Dan; Herskovits, Anat A

    2015-06-01

    Human multidrug efflux transporters are known for their ability to extrude antibiotics and toxic compounds out of cells, yet accumulating data indicate they have additional functions in diverse physiological processes not related to drug efflux. Here, we show that the human multidrug transporter P-glycoprotein (P-gp) (also named MDR1 and ABCB1) is transcriptionally induced in the monocytic cell line THP-1 upon infection with the human intracellular bacterial pathogen Listeria monocytogenes. Notably, we found that P-gp is important for full activation of the type I interferon response elicited against L. monocytogenes bacteria. Both inhibition of P-gp function by verapamil and inhibition of its transcription using mRNA silencing led to a reduction in the magnitude of the type I response in infected cells. This function of P-gp was specific to type I interferon cytokines elicited against cytosolic replicating bacteria and was not observed in response to cyclic di-AMP (c-di-AMP), a molecule that was shown to be secreted by L. monocytogenes during infection and to trigger type I interferons. Moreover, P-gp was not involved in activation of other proinflammatory cytokines, such as those triggered by vacuolar-restricted L. monocytogenes or lipopolysaccharide (LPS). Taken together, these findings demonstrate a role for P-gp in proper development of an innate immune response against intracellular pathogens, highlighting the complexity in employing therapeutic strategies that involve inhibition of multidrug resistance (MDR) efflux pumps.

  5. Structural intermediates in the fusion-associated transition of vesiculovirus glycoprotein.

    Science.gov (United States)

    Baquero, Eduard; Albertini, Aurélie A; Raux, Hélène; Abou-Hamdan, Abbas; Boeri-Erba, Elisabetta; Ouldali, Malika; Buonocore, Linda; Rose, John K; Lepault, Jean; Bressanelli, Stéphane; Gaudin, Yves

    2017-03-01

    Vesiculoviruses enter cells by membrane fusion, driven by a large, low-pH-induced, conformational change in the fusion glycoprotein G that involves transition from a trimeric pre-fusion toward a trimeric post-fusion state via monomeric intermediates. Here, we present the structure of the G fusion protein at intermediate pH for two vesiculoviruses, vesicular stomatitis virus (VSV) and Chandipura virus (CHAV), which is responsible for deadly encephalopathies. First, a CHAV G crystal structure shows two intermediate conformations forming a flat dimer of heterodimers. On virions, electron microscopy (EM) and tomography reveal monomeric spikes similar to one of the crystal conformations. In solution, mass spectrometry shows dimers of G. Finally, mutations at a dimer interface, involving fusion domains associated in an antiparallel manner to form an intermolecular β-sheet, affect G fusion properties. The location of the compensatory mutations restoring fusion activity strongly suggests that this interface is functionally relevant. This work reveals the range of G structural changes and suggests that G monomers can re-associate, through antiparallel interactions between fusion domains, into dimers that play a role at some early stage of the fusion process.

  6. DDX3 regulates cell growth through translational control of cyclin E1.

    Science.gov (United States)

    Lai, Ming-Chih; Chang, Wen-Cheng; Shieh, Sheau-Yann; Tarn, Woan-Yuh

    2010-11-01

    DDX3 belongs to the DEAD box family of RNA helicases, but the details of its biological function remain largely unclear. Here we show that knockdown of DDX3 expression impedes G(1)/S-phase transition of the cell cycle. To know how DDX3 may act in cell cycle control, we screened for cellular mRNA targets of DDX3. Many of the identified DDX3 targets encoded cell cycle regulators, including G(1)/S-specific cyclin E1. DDX3 depletion specifically downregulates translation of cyclin E1 mRNA. Moreover, our data suggest that DDX3 participates in translation initiation of targeted mRNAs as well as in cell growth control via its RNA helicase activity. Consistent with these findings, we show that in the temperature-sensitive DDX3 mutant hamster cell line tsET24, cyclin E1 expression is downregulated at a nonpermissive temperature that inactivates mutant DDX3. Taken together, our results indicate that DDX3 is critical for translation of cyclin E1 mRNA, which provides an alternative mechanism for regulating cyclin E1 expression during the cell cycle.

  7. Cooperative effects for CYP2E1 differ between styrene and its metabolites

    Science.gov (United States)

    Hartman, Jessica H.; Boysen, Gunnar; Miller, Grover P.

    2014-01-01

    Cooperative interactions are frequently observed in the metabolism of drugs and pollutants by cytochrome P450s; nevertheless, the molecular determinants for cooperativity remain elusive. Previously, we demonstrated that steady-state styrene metabolism by CYP2E1 exhibits positive cooperativity.We hypothesized that styrene metabolites have lower affinity than styrene toward CYP2E1 and limited ability to induce cooperative effects during metabolism. To test the hypothesis, we determined the potency and mechanism of inhibition for styrene and its metabolites toward oxidation of 4-nitrophenol using CYP2E1 Supersomes® and human liver microsomes.Styrene inhibited the reaction through a mixed cooperative mechanism with high affinity for the catalytic site (67 μM) and lower affinity for the cooperative site (1100 μM), while increasing substrate turnover at high concentrations. Styrene oxide and 4-vinylphenol possessed similar affinity for CYP2E1. Styrene oxide behaved cooperatively like styrene, but 4-vinylphenol decreased turnover at high concentrations. Styrene glycol was a very poor competitive inhibitor. Among all compounds, there was a positive correlation with binding and hydrophobicity.Taken together, these findings for CYP2E1 further validate contributions of cooperative mechanisms to metabolic processes, demonstrate the role of molecular structure on those mechanisms and underscore the potential for heterotropic cooperative effects between different compounds. PMID:23327532

  8. 2-Carboxyquinoxalines kill mycobacterium tuberculosis through noncovalent inhibition of DprE1.

    Science.gov (United States)

    Neres, João; Hartkoorn, Ruben C; Chiarelli, Laurent R; Gadupudi, Ramakrishna; Pasca, Maria Rosalia; Mori, Giorgia; Venturelli, Alberto; Savina, Svetlana; Makarov, Vadim; Kolly, Gaelle S; Molteni, Elisabetta; Binda, Claudia; Dhar, Neeraj; Ferrari, Stefania; Brodin, Priscille; Delorme, Vincent; Landry, Valérie; de Jesus Lopes Ribeiro, Ana Luisa; Farina, Davide; Saxena, Puneet; Pojer, Florence; Carta, Antonio; Luciani, Rosaria; Porta, Alessio; Zanoni, Giuseppe; De Rossi, Edda; Costi, Maria Paola; Riccardi, Giovanna; Cole, Stewart T

    2015-03-20

    Phenotypic screening of a quinoxaline library against replicating Mycobacterium tuberculosis led to the identification of lead compound Ty38c (3-((4-methoxybenzyl)amino)-6-(trifluoromethyl)quinoxaline-2-carboxylic acid). With an MIC99 and MBC of 3.1 μM, Ty38c is bactericidal and active against intracellular bacteria. To investigate its mechanism of action, we isolated mutants resistant to Ty38c and sequenced their genomes. Mutations were found in rv3405c, coding for the transcriptional repressor of the divergently expressed rv3406 gene. Biochemical studies clearly showed that Rv3406 decarboxylates Ty38c into its inactive keto metabolite. The actual target was then identified by isolating Ty38c-resistant mutants of an M. tuberculosis strain lacking rv3406. Here, mutations were found in dprE1, encoding the decaprenylphosphoryl-d-ribose oxidase DprE1, essential for biogenesis of the mycobacterial cell wall. Genetics, biochemical validation, and X-ray crystallography revealed Ty38c to be a noncovalent, noncompetitive DprE1 inhibitor. Structure-activity relationship studies generated a family of DprE1 inhibitors with a range of IC50's and bactericidal activity. Co-crystal structures of DprE1 in complex with eight different quinoxaline analogs provided a high-resolution interaction map of the active site of this extremely vulnerable target in M. tuberculosis.

  9. E1B and E4 oncoproteins of adenovirus antagonize the effect of apoptosis inducing factor

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Roberta L. [Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston-Salem, NC 27157 (United States); Wilkinson, John C., E-mail: john.wilkinson@ndsu.edu [Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157 (United States); Ornelles, David A., E-mail: ornelles@wakehealth.edu [Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston-Salem, NC 27157 (United States)

    2014-05-15

    Adenovirus inundates the productively infected cell with linear, double-stranded DNA and an abundance of single-stranded DNA. The cellular response to this stimulus is antagonized by the adenoviral E1B and E4 early genes. A mutant group C adenovirus that fails to express the E1B-55K and E4ORF3 genes is unable to suppress the DNA-damage response. Cells infected with this double-mutant virus display significant morphological heterogeneity at late times of infection and frequently contain fragmented nuclei. Nuclear fragmentation was due to the translocation of apoptosis inducing factor (AIF) from the mitochondria into the nucleus. The release of AIF was dependent on active poly(ADP-ribose) polymerase-1 (PARP-1), which appeared to be activated by viral DNA replication. Nuclear fragmentation did not occur in AIF-deficient cells or in cells treated with a PARP-1 inhibitor. The E1B-55K or E4ORF3 proteins independently prevented nuclear fragmentation subsequent to PARP-1 activation, possibly by altering the intracellular distribution of PAR-modified proteins. - Highlights: • E1B-55K or E4orf3 prevents nuclear fragmentation. • Nuclear fragmentation requires AIF and PARP-1 activity. • Adenovirus DNA replication activates PARP-1. • E1B-55K or E4orf3 proteins alter the distribution of PAR.

  10. Down-regulation of paramyxovirus hemagglutinin-neuraminidase glycoprotein surface expression by a mutant fusion protein containing a retention signal for the endoplasmic reticulum.

    Science.gov (United States)

    Tanaka, Y; Heminway, B R; Galinski, M S

    1996-08-01

    The human parainfluenza virus type 3 (HPIV3) fusion (F) and hemagglutinin-neuraminidase (HN) glycoproteins are the principal components involved in virion receptor binding, membrane penetration, and ultimately, syncytium formation. While the requirement for both F and HN in this process has been determined from recombinant expression studies, stable physical association of these proteins in coimmunoprecipitation studies has not been observed. In addition, coexpression of other heterologous paramyxovirus F or HN glycoproteins with either HPIV3 F or HN does not result in the formation of syncytia, suggesting serotype-specific protein differences. In this study, we report that simian virus 5 and Sendai virus heterologous HN proteins and measles virus hemagglutinin (H) were found to be down-regulated when coexpressed with HPIV3 F. As an alternative to detecting physical associations of these proteins by coimmunoprecipitation, further studies were performed with a mutant HPIV3 F protein (F-KDEL) lacking a transmembrane anchor and cytoplasmic tail and containing a carboxyl-terminal retention signal for the endoplasmic reticulum (ER). F-KDEL was defective for transport to the cell surface and could down-regulate surface expression of HPIV3 HN and heterologous HN/H proteins from simian virus 5, Sendai virus, and measles virus in coexpression experiments. HN/H down-regulation appeared to result, in part, from an early block to HPIV3 HN synthesis, as well as an instability of the heterologous HN/H proteins within the ER. In contrast, coexpression of F-KDEL with HPIV3 wild-type F or the heterologous receptor-binding proteins, respiratory syncytial virus glycoprotein (G) and vesicular stomatitis virus glycoprotein (G), were not affected in transport to the cell surface. Together, these results support the notion that the reported serotype-specific restriction of syncytium formation may involve, in part, down-regulation of heterologous HN expression.

  11. Structural comparison of cytochromes P450 2A6, 2A13, and 2E1 with pilocarpine

    Energy Technology Data Exchange (ETDEWEB)

    DeVore, Natasha M.; Meneely, Kathleen M.; Bart, Aaron G.; Stephens, Eva S.; Battaile, Kevin P.; Scott, Emily E. (Kansas); (HWMRI)

    2013-11-20

    Human xenobiotic-metabolizing cytochrome P450 (CYP) enzymes can each bind and monooxygenate a diverse set of substrates, including drugs, often producing a variety of metabolites. Additionally, a single ligand can interact with multiple CYP enzymes, but often the protein structural similarities and differences that mediate such overlapping selectivity are not well understood. Even though the CYP superfamily has a highly canonical global protein fold, there are large variations in the active site size, topology, and conformational flexibility. We have determined how a related set of three human CYP enzymes bind and interact with a common inhibitor, the muscarinic receptor agonist drug pilocarpine. Pilocarpine binds and inhibits the hepatic CYP2A6 and respiratory CYP2A13 enzymes much more efficiently than the hepatic CYP2E1 enzyme. To elucidate key residues involved in pilocarpine binding, crystal structures of CYP2A6 (2.4 {angstrom}), CYP2A13 (3.0 {angstrom}), CYP2E1 (2.35 {angstrom}), and the CYP2A6 mutant enzyme, CYP2A6 I208S/I300F/G301A/S369G (2.1 {angstrom}) have been determined with pilocarpine in the active site. In all four structures, pilocarpine coordinates to the heme iron, but comparisons reveal how individual residues lining the active sites of these three distinct human enzymes interact differently with the inhibitor pilocarpine.

  12. Reactive oxygen species regulatory mechanisms associated with rapid response of MC3T3-E1 cells for vibration stress

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ling; Gan, Xueqi; Zhu, Zhuoli; Yang, Yang; He, Yuting; Yu, Haiyang, E-mail: yhyang6812@scu.edu.cn

    2016-02-12

    Although many previous studies have shown that refractory period-dependent memory effect of vibration stress is anabolic for skeletal homeostasis, little is known about the rapid response of osteoblasts simply derived from vibration itself. In view of the potential role of reactive oxygen species (ROS) in mediating differentiated activity of osteoblasts, whether and how ROS regulates the rapid effect of vibration deserve to be demonstrated. Our findings indicated that MC3T3-E1 cells underwent decreased gene expression of Runx2, Col-I and ALP and impaired ALP activity accompanied by increased mitochondrial fission immediately after vibration loading. Moreover, we also revealed the involvement of ERK-Drp1 signal transduction in ROS regulatory mechanisms responsible for the rapid effect of vibration stress. - Highlights: • ROS contributed to the rapid response of MC3T3-E1 cells for vibration stress. • Imbalance of mitochondrial dynamics were linked to the LMHFV-derived rapid response. • The role of ERK-Drp1 signal pathway in the LMHFV-derived osteoblast rapid response.

  13. Calcification of MC3T3-E1 cells on titanium and zirconium.

    Science.gov (United States)

    Umezawa, Takayuki; Chen, Peng; Tsutsumi, Yusuke; Doi, Hisashi; Ashida, Maki; Suzuki, Shoichi; Moriyama, Keiji; Hanawa, Takao

    2015-01-01

    To confirm similarity of hard tissue compatibility between titanium and zirconium, calcification of MC3T3-E1 cells on titanium and zirconium was evaluated in this study. Mirror-polished titanium (Ti) and zirconium (Zr) disks and zirconium-sputter deposited titanium (Zr/Ti) were employed in this study. The surface of specimens were characterized using scanning electron microscopy and X-ray diffraction. Then, the cellular proliferation, differentiation and calcification of MC3T3-E1 cells on specimens were investigated. The surface of Zr/Ti was much smoother and cleaner than those of Ti and Zr. The proliferation of the cell was the same among three specimens, while the differentiation and calcification on Zr/Ti were faster than those on Ti and Zr. Therefore, Ti and Zr showed the identical hard tissue compatibility according to the evaluation with MC3T3-E1 cells. Sputter deposition may improve cytocompatibility.

  14. Double ion beams and accelerated ions observed by SWIDs on Chang'E-1

    Science.gov (United States)

    Kong, Linggao; Zhang, Aibing; Wang, Shijin

    2012-07-01

    Chang'E-1 is the first Chinese lunar exploration spacecraft launced in 2007. Solar Wind Ion Detectors(SWIDs) are two scientific instruments on Chang'E-1 to measure the solar wind and the plasma environment around the Moon. Some cases of double ion beams in solar wind were observed by SWIDs. These double ion beams present double proton beams with a single alpha beam. Another insteresting phenomenon observed by SWIDs is the accelerated ions when the spacecraft was over the magnetic anomalies. The magnetic anomaly may induce mini-magnetosphere, which was confirmed both by simulation and measurement of some other lunar exploration spacecrafts. The accelerated ions observed by Chang'E-1 may be the result of the interaction of the solar wind and the mini-magnetosphere of the Moon.

  15. Influence of Lactobacillus E1 on the Storage Stability in Emulsion Immobilization

    Institute of Scientific and Technical Information of China (English)

    SUN Xin; CHEN Xiguang; LIU Chengsheng; CHA Dongsu; PENG Hongni

    2009-01-01

    A coacervation method with double emulsion strategy (w/o/w) was used to prepare immobilized Lactobacillus E1. Diatomite was chosen as the carrier for bacteria. Sodium alginate,dextrin and gelatin were used as protective solutes for the preservation of Lactobacillus E1 and their effects on the storage viability during storage were discussed. The influence of storage temperature on the storage viability was also examined. The results show that high bacteria viable count over 109 cfu/g for an extended shelf life of 37 d can be achieved with 2% sodium alginate, 5% dextrin and 4% gelatin as protective solutes, at 10 ℃ of the storage temperature. This immobilized Lactobacillus E1 has potential use as functional food ingredient for both human dairy food and animal feedstuff.

  16. Melanoma cultures show different susceptibility towards E1A-, E1B-19 kDa- and fiber-modified replication-competent adenoviruses.

    Science.gov (United States)

    Schmitz, M; Graf, C; Gut, T; Sirena, D; Peter, I; Dummer, R; Greber, U F; Hemmi, S

    2006-06-01

    Replicating adenovirus (Ad) vectors with tumour tissue specificity hold great promise for treatment of cancer. We have recently constructed a conditionally replicating Ad5 AdDeltaEP-TETP inducing tumour regression in a xenograft mouse model. For further improvement of this vector, we introduced four genetic modifications and analysed the viral cytotoxicity in a large panel of melanoma cell lines and patient-derived melanoma cells. (1) The antiapoptotic gene E1B-19 kDa (Delta19 mutant) was deleted increasing the cytolytic activity in 18 of 21 melanoma cells. (2) Introduction of the E1A 122-129 deletion (Delta24 mutant), suggested to attenuate viral replication in cell cycle-arrested cells, did not abrogate this activity and increased the cytolytic activity in two of 21 melanoma cells. (3) We inserted an RGD sequence into the fiber to extend viral tropism to alphav integrin-expressing cells, and (4) swapped the fiber with the Ad35 fiber (F35) enhancing the tropism to malignant melanoma cells expressing CD46. The RGD-fiber modification strongly increased cytolysis in all of the 11 CAR-low melanoma cells. The F35 fiber-chimeric vector boosted the cytotoxicity in nine of 11 cells. Our results show that rational engineering additively enhances the cytolytic potential of Ad vectors, a prerequisite for the development of patient-customized viral therapies.

  17. Herpes simplex virus glycoproteins gB and gD function in a redundant fashion to promote secondary envelopment.

    Science.gov (United States)

    Johnson, David C; Wisner, Todd W; Wright, Catherine C

    2011-05-01

    Egress of herpes simplex virus (HSV) and other herpesviruses from cells involves extensive modification of cellular membranes and sequential envelopment and deenvelopment steps. HSV glycoproteins are important in these processes, and frequently two or more glycoproteins can largely suffice in any step. Capsids in the nucleus undergo primary envelopment at the inner nuclear membrane (INM), and then enveloped virus particles undergo deenvelopment by fusing with the outer nuclear membrane (ONM). Capsids delivered into the cytoplasm then undergo secondary envelopment, involving trans-Golgi network (TGN) membranes. The deenvelopment step involves HSV glycoproteins gB and gH/gL acting in a redundant fashion. This fusion has features common to the fusion that occurs between the virion envelope and cellular membranes when HSV enters cells, a process requiring gB, gD, and gH/gL. Whether HSV gD also participates (in a redundant fashion with gB or gH/gL) in deenvelopment has not been characterized. Secondary envelopment in the cytoplasm is known to involve HSV gD and gE/gI, also acting in a redundant fashion. Whether gB might also contribute to secondary envelopment, collaborating with gD and gE/gI, is also not clear. To address these questions, we constructed an HSV double mutant lacking gB and gD. The HSV gB(-)/gD(-) mutant exhibited no substantial defects in nuclear egress. In contrast, secondary envelopment was markedly reduced, and there were numerous unenveloped capsids that accumulated in the cytoplasm, as well as increased numbers of partially enveloped capsids and morphologically aberrant enveloped particles with thicker, oblong tegument layers. These defects were different from those observed with HSV gD(-)/gE(-)/gI(-) mutants, which accumulated capsids in large, aggregated masses in the cytoplasm. Our results suggest that HSV gB functions in secondary envelopment, apparently acting downstream of gE/gI.

  18. Inhibitory Potency of 4-Carbon Alkanes and Alkenes toward CYP2E1 Activity

    Science.gov (United States)

    Hartman, Jessica H.; Miller, Grover P.; Boysen, Gunnar

    2016-01-01

    CYP2E1 has been implicated in the bioactivation of many small molecules into reactive metabolites which form adducts with proteins and DNA, and thus a better understanding of the molecular determinants of its selectivity are critical for accurate toxicological predictions. In this study, we determined the potency of inhibition of human CYP2E1 for various 4-carbon alkanes, alkenes and alcohols. In addition, known CYP2E1 substrates and inhibitors including 4-methylpyrazole, aniline, and dimethylnitrosamine were included to determine their relative potencies. Of the 1,3-butadiene-derived metabolites studied, 3,4-epoxy-1-butene was the strongest inhibitor with an IC50 of 110 μM compared to 1700 μM and 6600 μM for 1,2-butenediol and 1,2:3,4-diepoxybutane, respectively. Compared to known inhibitors, inhibitory potency of 3,4-epoxy-1-butene is between 4-methylpyrazole (IC50 = 1.8 μM) and dimethylnitrosamine (IC50 = 230 μM). All three butadiene metabolites inhibit CYP2E1 activity through a simple competitive mechanism. Among the 4-carbon compounds studied, the presence and location of polar groups seems to influence inhibitory potency. To further examine this notion, the investigation was extended to include structurally and chemically similar analogs, including propylene oxide and various butane alcohols. Those results demonstrated preferential recognition of CYP2E1 toward the type and location of polar and hydrophobic structural elements. Taken together, CYP2E1 metabolism may be modified in vivo by exposure to 4-carbon compounds, such as drugs, and nutritional constituents, a finding that highlights the complexity of exposure to mixtures. PMID:24561005

  19. Propolis protects CYP 2E1 enzymatic activity and oxidative stress induced by carbon tetrachloride.

    Science.gov (United States)

    Bhadauria, Monika; Nirala, Satendra Kumar; Shukla, Sangeeta

    2007-08-01

    Induction of CYP 2E1 by carbon tetrachloride (CCl(4)) is one of the central pathways by which CCl(4) generates oxidative stress in hepatocytes. Experimental liver injury was induced in rats by CCl(4) to determine toxicological actions on CYP 2E1 by microsomal drug metabolizing enzymes. In this report, ethanolic extract of propolis at a dose of 200 mg/kg (po) was used after 24 h of toxicant administration to validate its protective potential. Intraperitoneal injection of CCl(4) (1.5 ml/kg) induced hepatotoxicity after 24 h of its administration that was associated with elevated malonyldialdehyde (index of lipid peroxidation), lactate dehydrogenase and gamma-glutamyl transpeptidase release (index of a cytotoxic effect). Hepatic microsomal drug metabolizing enzymes of CYP 2E1 showed sharp depletion as assessed by estimating aniline hydroxylase and amidopyrine N-demethylase activity after CCl(4) exposure. Toxic effect of CCl(4) was evident on CYP 2E1 activity by increased hexobarbitone induced sleep time and bromosulphalein retention. Propolis extract showed significant improvement in the activity of both enzymes and suppressed toxicant induced increase in sleep time and bromosulphalein retention. Choleretic activity of liver did not show any sign of toxicity after propolis treatment at a dose of 200 mg/kg (id). Histopathological evaluation of the liver revealed that propolis reduced the incidence of liver lesions including hepatocyte swelling and lymphocytic infiltrations induced by CCl(4). Electron microscopic observations also showed improvement in ultrastructure of liver and substantiated recovery in biochemical parameters. Protective activity of propolis at 200 mg/kg dose was statistically compared with positive control silymarin (50 mg/kg, po), a known hepatoprotective drug seems to be better in preventing hepatic CYP 2E1 activity deviated by CCl(4). These results lead us to speculate that propolis may play hepatoprotective role via improved CYP 2E1 activity and

  20. Functional characterisation of an engineered multidomain human P450 2E1 by molecular Lego.

    Science.gov (United States)

    Fairhead, Michael; Giannini, Silva; Gillam, Elizabeth M J; Gilardi, Gianfranco

    2005-12-01

    The human cytochrome P450s constitute an important family of monooxygenase enzymes that carry out essential roles in the metabolism of endogenous compounds and foreign chemicals. We present here results of a fusion between a human P450 enzyme and a bacterial reductase that for the first time is shown does not require the addition of lipids or detergents to achieve wild-type-like activities. The fusion enzyme, P450 2E1-BMR, contains the N-terminally modified residues 22-493 of the human P450 2E1 fused at the C-terminus to residues 473-1049 of the P450 BM3 reductase (BMR). The P450 2E1-BMR enzyme is active, self-sufficient and presents the typical marker activities of the native human P450 2E1: the hydroxylation of p-nitrophenol (KM=1.84+/-0.09 mM and kcat of 2.98+/-0.04 nmol of p-nitrocatechol formed per minute per nanomole of P450) and chlorzoxazone (KM=0.65+/-0.08 mM and kcat of 0.95+/-0.10 nmol of 6-hydroxychlorzoxazone formed per minute per nanomole of P450). A 3D model of human P450 2E1 was generated to rationalise the functional data and to allow an analysis of the surface potentials. The distribution of charges on the model of P450 2E1 compared with that of the FMN domain of BMR provides the ground for the understanding of the interaction between the fused domains. The results point the way to successfully engineer a variety of catalytically self-sufficient human P450 enzymes for drug metabolism studies in solution.

  1. An analysis of amino acid sequences surrounding archaeal glycoprotein sequons.

    Science.gov (United States)

    Abu-Qarn, Mehtap; Eichler, Jerry

    2007-05-01

    Despite having provided the first example of a prokaryal glycoprotein, little is known of the rules governing the N-glycosylation process in Archaea. As in Eukarya and Bacteria, archaeal N-glycosylation takes place at the Asn residues of Asn-X-Ser/Thr sequons. Since not all sequons are utilized, it is clear that other factors, including the context in which a sequon exists, affect glycosylation efficiency. As yet, the contribution to N-glycosylation made by sequon-bordering residues and other related factors in Archaea remains unaddressed. In the following, the surroundings of Asn residues confirmed by experiment as modified were analyzed in an attempt to define sequence rules and requirements for archaeal N-glycosylation.

  2. An analysis of amino acid sequences surrounding archaeal glycoprotein sequons

    Directory of Open Access Journals (Sweden)

    Mehtap Abu-Qarn

    2006-01-01

    Full Text Available Despite having provided the first example of a prokaryal glycoprotein, little is known of the rules governing the N-glycosylation process in Archaea. As in Eukarya and Bacteria, archaeal N-glycosylation takes place at the Asn residues of Asn-X-Ser/Thr sequons. Since not all sequons are utilized, it is clear that other factors, including the context in which a sequon exists, affect glycosylation efficiency. As yet, the contribution to N-glycosylation made by sequon-bordering residues and other related factors in Archaea remains unaddressed. In the following, the surroundings of Asn residues confirmed by experiment as modified were analyzed in an attempt to define sequence rules and requirements for archaeal N-glycosylation.

  3. Myelin-associated glycoprotein and its axonal receptors.

    Science.gov (United States)

    Schnaar, Ronald L; Lopez, Pablo H H

    2009-11-15

    Myelin-associated glycoprotein (MAG) is expressed on the innermost myelin membrane wrap, directly apposed to the axon surface. Although it is not required for myelination, MAG enhances long-term axon-myelin stability, helps to structure nodes of Ranvier, and regulates the axon cytoskeleton. In addition to its role in axon-myelin stabilization, MAG inhibits axon regeneration after injury; MAG and a discrete set of other molecules on residual myelin membranes at injury sites actively signal axons to halt elongation. Both the stabilizing and the axon outgrowth inhibitory effects of MAG are mediated by complementary MAG receptors on the axon surface. Two MAG receptor families have been described, sialoglycans (specifically gangliosides GD1a and GT1b) and Nogo receptors (NgRs). Controversies remain about which receptor(s) mediates which of MAG's biological effects. Here we review the findings and challenges in associating MAG's biological effects with specific receptors.

  4. Small-angle scattering study of Aspergillus awamori glycoprotein glucoamylase

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, A. E., E-mail: schmidt@omrb.pnpi.spb.ru; Shvetsov, A. V. [National Research Center “Kurchatov Institute”, Konstantinov Petersburg Nuclear Physics Institute (Russian Federation); Kuklin, A. I. [Joint Institute for Nuclear Research (Russian Federation); Lebedev, D. V.; Surzhik, M. A.; Sergeev, V. R.; Isaev-Ivanov, V. V. [National Research Center “Kurchatov Institute”, Konstantinov Petersburg Nuclear Physics Institute (Russian Federation)

    2016-01-15

    Glucoamylase from fungus Aspergillus awamori is glycoside hydrolase that catalyzes the hydrolysis of α-1,4- and α-1,6-glucosidic bonds in glucose polymers and oligomers. This glycoprotein consists of a catalytic domain and a starch-binding domain connected by an O-glycosylated polypeptide chain. The conformation of the linker, the relative arrangement of the domains, and the structure of the full-length enzyme are unknown. The structure of the recombinant glucoamylase GA1 was studied by molecular modelling and small-angle neutron scattering (SANS) methods. The experimental SANS data provide evidence that glucoamylase exists as a monomer in solution and contains a glycoside component, which makes a substantial contribution to the scattering. The model of full-length glucoamylase, which was calculated without taking into account the effect of glycosylation, is consistent with the experimental data and has a radius of gyration of 33.4 ± 0.6 Å.

  5. INTERFERON SELECTIVELY INHIBITS THE SYNTHESIS OF MAYARO VIRUS GLYCOPROTEINS

    Directory of Open Access Journals (Sweden)

    Davis F. Ferreira

    1998-09-01

    Full Text Available We have previously observed that interferon (recIFNa2b blocks the process of morphogenesis of Mayaro virus in TC7 cells (monkey kidney. In this work we show that IFNa inhibits preferentially virus glycoproteins and their precursors, and this effect is probably correlated to the alterations in the morphogenesis process previously observed.Observamos anteriormente que o Interferon (IFN recombinante a2b bloqueia o processo de morfogênese do vírus Mayaro em células TC7 (rim de macaco. Neste trabalho demonstramos que o IFNa inibe preferencialmente as glicoproteínas virais e seus precursores e que este efeito está, provavelmente, correlacionado com as alterações no processo de morfogênese previamente observadas.

  6. Small-angle scattering study of Aspergillus awamori glycoprotein glucoamylase

    Science.gov (United States)

    Schmidt, A. E.; Shvetsov, A. V.; Kuklin, A. I.; Lebedev, D. V.; Surzhik, M. A.; Sergeev, V. R.; Isaev-Ivanov, V. V.

    2016-01-01

    Glucoamylase from fungus Aspergillus awamori is glycoside hydrolase that catalyzes the hydrolysis of α-1,4- and α-1,6-glucosidic bonds in glucose polymers and oligomers. This glycoprotein consists of a catalytic domain and a starch-binding domain connected by an O-glycosylated polypeptide chain. The conformation of the linker, the relative arrangement of the domains, and the structure of the full-length enzyme are unknown. The structure of the recombinant glucoamylase GA1 was studied by molecular modelling and small-angle neutron scattering (SANS) methods. The experimental SANS data provide evidence that glucoamylase exists as a monomer in solution and contains a glycoside component, which makes a substantial contribution to the scattering. The model of full-length glucoamylase, which was calculated without taking into account the effect of glycosylation, is consistent with the experimental data and has a radius of gyration of 33.4 ± 0.6 Å.

  7. Structure of the Epstein-Barr virus major envelope glycoprotein.

    Science.gov (United States)

    Szakonyi, Gerda; Klein, Michael G; Hannan, Jonathan P; Young, Kendra A; Ma, Runlin Z; Asokan, Rengasamy; Holers, V Michael; Chen, Xiaojiang S

    2006-11-01

    Epstein-Barr virus (EBV) infection of B cells is associated with lymphoma and other human cancers. EBV infection is initiated by the binding of the viral envelope glycoprotein (gp350) to the cell surface receptor CR2. We determined the X-ray structure of the highly glycosylated gp350 and defined the CR2 binding site on gp350. Polyglycans shield all but one surface of the gp350 polypeptide, and we demonstrate that this glycan-free surface is the receptor-binding site. Deglycosylated gp350 bound CR2 similarly to the glycosylated form, suggesting that glycosylation is not important for receptor binding. Structure-guided mutagenesis of the glycan-free surface disrupted receptor binding as well as binding by a gp350 monoclonal antibody, a known inhibitor of virus-receptor interactions. These results provide structural information for developing drugs and vaccines to prevent infection by EBV and related viruses.

  8. Variation in the Major Surface Glycoprotein Genes in Pneumocystis jirovecii

    Science.gov (United States)

    Kutty, Geetha; Maldarelli, Frank; Achaz, Guillaume; Kovacs, Joseph A.

    2008-01-01

    The genome of Pneumocystis, which causes life-threatening pneumonia in immunosuppressed patients, contains a multi-copy gene family that encodes the major surface glycoprotein (Msg). Pneumocystis can vary the expressed Msg, presumably as a mechanism to avoid host immune responses. Analysis of 24 msg gene sequences obtained from a single human Pneumocystis isolate demonstrated that the sequences segregate into two branches. Based on a number of analyses, recombination among msg genes appears to be an important mechanism for generating msg diversity. Intra-branch recombination occurred more frequently than inter-branch recombination. Restriction fragment length polymorphism analysis demonstrated substantial variation in the repertoire of the msg gene family among isolates of human Pneumocystis, which was not observed in laboratory isolates of rat or mouse Pneumocystis; this may be the result of examining outbred vs. captive populations. Increased diversity in the Msg repertoire, generated in part by recombination, increases the potential for antigenic variation in this abundant surface protein. PMID:18627244

  9. Immunoglobulin-E reactivity to wine glycoproteins in heavy drinkers

    DEFF Research Database (Denmark)

    Gonzalez-Quintela, Arturo; Gomez-Rial, Jose; Valcarcel, Catalina;

    2011-01-01

    and biological significance of IgE antibodies to N-glycans from wine glycoproteins in heavy drinkers. A structured questionnaire, skin prick tests, serum IgE levels, IgE-immunoblotting to wine extracts, and basophil activation tests were used to characterize 20 heavy drinkers and 10 control subjects. Eleven...... heavy drinkers (55%) showed IgE binding to proteins in wine extracts. The proteins were identified by mass spectrometry as grape-derived vacuolar invertase and thaumatin-like protein. Immunoblot reactivity was closely associated with the presence of IgE to CCDs and was inhibited by preincubation...... with a glycoconjugate containing bromelain-type N-glycans. The same conjugate, CCD-bearing allergens, and wine extracts activated basophils in patients with high-titer CCD-specific IgE but not in healthy controls. There was no relationship between immunoblot reactivity and consumption of any specific type of wine...

  10. Bioskin as an affinity matrix for the separation of glycoproteins.

    Science.gov (United States)

    Vicente, C; Sebastián, B; Fontaniella, B; Márquez, A; Xavier Filho, L; Legaz, M E

    2001-05-11

    Bioskin is a natural product produced by a mixed culture of Acetobacter xylinum, Saccharomyces cerevisiae and S. pombe cultured on media containing sucrose. It is of fibrillar nature able to retain some proteins, such as cytochrome c, by adsorption, and mainly composed of glucosamine and N-acetyl-D-glucosamine. This makes it possible that, at an adequate pH value, proteins charged as polyanionic molecules, such as catalase, can be retained by ionic adsorption using the positively charged amino groups of the matrix. In addition, bioskin can also be used as an affinity matrix to retain glycoproteins able to perform specific affinity reactions with the amino sugars of the matrix, such as invertase, fetuin or ovalbumin. Its possible use as a chromatographic support is discussed.

  11. DDX3 Regulates Cell Growth through Translational Control of Cyclin E1▿ †

    OpenAIRE

    2010-01-01

    DDX3 belongs to the DEAD box family of RNA helicases, but the details of its biological function remain largely unclear. Here we show that knockdown of DDX3 expression impedes G1/S-phase transition of the cell cycle. To know how DDX3 may act in cell cycle control, we screened for cellular mRNA targets of DDX3. Many of the identified DDX3 targets encoded cell cycle regulators, including G1/S-specific cyclin E1. DDX3 depletion specifically downregulates translation of cyclin E1 mRNA. Moreover, ...

  12. Thionin-D4E1 chimeric protein protects plants against bacterial infections

    Energy Technology Data Exchange (ETDEWEB)

    Stover, Eddie W; Gupta, Goutam; Hao, Guixia

    2017-08-08

    The generation of a chimeric protein containing a first domain encoding either a pro-thionon or thionin, a second domain encoding D4E1 or pro-D4E1, and a third domain encoding a peptide linker located between the first domain and second domain is described. Either the first domain or the second domain is located at the amino terminal of the chimeric protein and the other domain (second domain or first domain, respectively) is located at the carboxyl terminal. The chimeric protein has antibacterial activity. Genetically altered plants and their progeny expressing a polynucleotide encoding the chimeric protein resist diseases caused by bacteria.

  13. Improvements and Testing Practical Expressions for Photon Strength Functions of E1 Gamma-Transitions

    CERN Document Server

    Plujko, Vladimir; Kadenko, Igor; Solodovnyk, Kateryna

    2016-01-01

    Analytical expression for the E1 photon strength functions (PSF) is modified to account for the low-energy enhancement due to nuclear structure effects (presence of low-energy state (LES)). A closed-form expression of the E1 PSF function includes response of two nuclear states: LES and giant diplole resonance (GDR). Expression for the nuclear response function on electromagnetic field is based on a model of excitation of two coupled damped states. These approach is tested for different data sets for spherical nuclei. Impact on PSF shape of coupling between LES and GDR excitations is considered.

  14. E1A genes of adenovirus type 2 and type 5 are expressed at different levels

    DEFF Research Database (Denmark)

    Moritz, Constanze; Dobbelstein, Matthias

    2006-01-01

    Adenoviruses are an extensively studied system for modeling oncogenesis and for experimental cancer therapy. The most commonly analyzed virus types are 2 and 5, and little distinction has been made between them in past studies. Adenoviruses used for therapeutic purposes are frequently hybrids...... region. We found that the hybrid viruses replicated with considerably lower efficiency than their type 5 counterparts in H1299 cells (dl309:WtD = 3-4, dl338:dl1520 > 10). Moreover, adenovirus type 2 E1A expression from the hybrid viruses was strongly reduced in comparison to adenovirus type 5 E1A...

  15. The first human epitope map of the alphaviral E1 and E2 proteins reveals a new E2 epitope with significant virus neutralizing activity.

    Directory of Open Access Journals (Sweden)

    Ann R Hunt

    2010-07-01

    Full Text Available Venezuelan equine encephalitis virus (VEEV is responsible for VEE epidemics that occur in South and Central America and the U.S. The VEEV envelope contains two glycoproteins E1 (mediates cell membrane fusion and E2 (binds receptor and elicits virus neutralizing antibodies. Previously we constructed E1 and E2 epitope maps using murine monoclonal antibodies (mMAbs. Six E2 epitopes (E2(c,d,e,f,g,h bound VEEV-neutralizing antibody and mapped to amino acids (aa 182-207. Nothing is known about the human antibody repertoire to VEEV or epitopes that engage human virus-neutralizing antibodies. There is no specific treatment for VEE; however virus-neutralizing mMAbs are potent protective and therapeutic agents for mice challenged with VEEV by either peripheral or aerosol routes. Therefore, fully human MAbs (hMAbs with virus-neutralizing activity should be useful for prevention or clinical treatment of human VEE.We used phage-display to isolate VEEV-specific hFabs from human bone marrow donors. These hFabs were characterized by sequencing, specificity testing, VEEV subtype cross-reactivity using indirect ELISA, and in vitro virus neutralization capacity. One E2-specific neutralizing hFAb, F5n, was converted into IgG, and its binding site was identified using competitive ELISA with mMAbs and by preparing and sequencing antibody neutralization-escape variants.Using 11 VEEV-reactive hFabs we constructed the first human epitope map for the alphaviral surface proteins E1 and E2. We identified an important neutralization-associated epitope unique to the human immune response, E2 aa115-119. Using a 9 A resolution cryo-electron microscopy map of the Sindbis virus E2 protein, we showed the probable surface location of this human VEEV epitope.The VEEV-neutralizing capacity of the hMAb F5 nIgG is similar to that exhibited by the humanized mMAb Hy4 IgG. The Hy4 IgG has been shown to limit VEEV infection in mice both prophylactically and therapeutically. Administration

  16. The first human epitope map of the alphaviral E1 and E2 proteins reveals a new E2 epitope with significant virus neutralizing activity.

    Directory of Open Access Journals (Sweden)

    Ann R Hunt

    Full Text Available BACKGROUND: Venezuelan equine encephalitis virus (VEEV is responsible for VEE epidemics that occur in South and Central America and the U.S. The VEEV envelope contains two glycoproteins E1 (mediates cell membrane fusion and E2 (binds receptor and elicits virus neutralizing antibodies. Previously we constructed E1 and E2 epitope maps using murine monoclonal antibodies (mMAbs. Six E2 epitopes (E2(c,d,e,f,g,h bound VEEV-neutralizing antibody and mapped to amino acids (aa 182-207. Nothing is known about the human antibody repertoire to VEEV or epitopes that engage human virus-neutralizing antibodies. There is no specific treatment for VEE; however virus-neutralizing mMAbs are potent protective and therapeutic agents for mice challenged with VEEV by either peripheral or aerosol routes. Therefore, fully human MAbs (hMAbs with virus-neutralizing activity should be useful for prevention or clinical treatment of human VEE. METHODS: We used phage-display to isolate VEEV-specific hFabs from human bone marrow donors. These hFabs were characterized by sequencing, specificity testing, VEEV subtype cross-reactivity using indirect ELISA, and in vitro virus neutralization capacity. One E2-specific neutralizing hFAb, F5n, was converted into IgG, and its binding site was identified using competitive ELISA with mMAbs and by preparing and sequencing antibody neutralization-escape variants. FINDINGS: Using 11 VEEV-reactive hFabs we constructed the first human epitope map for the alphaviral surface proteins E1 and E2. We identified an important neutralization-associated epitope unique to the human immune response, E2 aa115-119. Using a 9 A resolution cryo-electron microscopy map of the Sindbis virus E2 protein, we showed the probable surface location of this human VEEV epitope. CONCLUSIONS: The VEEV-neutralizing capacity of the hMAb F5 nIgG is similar to that exhibited by the humanized mMAb Hy4 IgG. The Hy4 IgG has been shown to limit VEEV infection in mice both

  17. In silico-based vaccine design against Ebola virus glycoprotein

    Directory of Open Access Journals (Sweden)

    Dash R

    2017-03-01

    Full Text Available Raju Dash,1 Rasel Das,2 Md Junaid,3 Md Forhad Chowdhury Akash,4 Ashekul Islam,5 SM Zahid Hosen1 1Molecular Modeling and Drug Design Laboratory (MMDDL, Pharmacology Research Division, Bangladesh Council of Scientific and Industrial Research (BCSIR, Chittagong, Bangladesh; 2Nanotechnology and Catalysis Research Center, University of Malaya, Kuala Lumpur, Malaysia; 3Department of Pharmaceutical Sciences, North South University, Dhaka, Bangladesh; 4Department of Pharmacy, BGC Trust University Bangladesh, Chittagong, Bangladesh; 5Department of Biochemistry and Molecular Biology, University of Chittagong, Chittagong, Bangladesh Abstract: Ebola virus (EBOV is one of the lethal viruses, causing more than 24 epidemic outbreaks to date. Despite having available molecular knowledge of this virus, no definite vaccine or other remedial agents have been developed yet for the management and avoidance of EBOV infections in humans. Disclosing this, the present study described an epitope-based peptide vaccine against EBOV, using a combination of B-cell and T-cell epitope predictions, followed by molecular docking and molecular dynamics simulation approach. Here, protein sequences of all glycoproteins of EBOV were collected and examined via in silico methods to determine the most immunogenic protein. From the identified antigenic protein, the peptide region ranging from 186 to 220 and the sequence HKEGAFFLY from the positions of 154–162 were considered the most potential B-cell and T-cell epitopes, correspondingly. Moreover, this peptide (HKEGAFFLY interacted with HLA-A*32:15 with the highest binding energy and stability, and also a good conservancy of 83.85% with maximum population coverage. The results imply that the designed epitopes could manifest vigorous enduring defensive immunity against EBOV. Keywords: Ebola virus, epitope, glycoprotein, vaccine design

  18. Crystal Structure of the Human Cytomegalovirus Glycoprotein B.

    Directory of Open Access Journals (Sweden)

    Heidi G Burke

    2015-10-01

    Full Text Available Human cytomegalovirus (HCMV, a dsDNA, enveloped virus, is a ubiquitous pathogen that establishes lifelong latent infections and caused disease in persons with compromised immune systems, e.g., organ transplant recipients or AIDS patients. HCMV is also a leading cause of congenital viral infections in newborns. Entry of HCMV into cells requires the conserved glycoprotein B (gB, thought to function as a fusogen and reported to bind signaling receptors. gB also elicits a strong immune response in humans and induces the production of neutralizing antibodies although most anti-gB Abs are non-neutralizing. Here, we report the crystal structure of the HCMV gB ectodomain determined to 3.6-Å resolution, which is the first atomic-level structure of any betaherpesvirus glycoprotein. The structure of HCMV gB resembles the postfusion structures of HSV-1 and EBV homologs, establishing it as a new member of the class III viral fusogens. Despite structural similarities, each gB has a unique domain arrangement, demonstrating structural plasticity of gB that may accommodate virus-specific functional requirements. The structure illustrates how extensive glycosylation of the gB ectodomain influences antibody recognition. Antigenic sites that elicit neutralizing antibodies are more heavily glycosylated than those that elicit non-neutralizing antibodies, which suggest that HCMV gB uses glycans to shield neutralizing epitopes while exposing non-neutralizing epitopes. This glycosylation pattern may have evolved to direct the immune response towards generation of non-neutralizing antibodies thus helping HCMV to avoid clearance. HCMV gB structure provides a starting point for elucidation of its antigenic and immunogenic properties and aid in the design of recombinant vaccines and monoclonal antibody therapies.

  19. ZIP1 and zinc inhibits fluoride-induced apoptosis in MC3T3-E1 cells.

    Science.gov (United States)

    Xu, Shihong; Yang, Yongliang; Han, Shumei; Wu, Zonghui

    2014-06-01

    Excess fluoride intake could induce apoptosis in the cells. As an essential micronutrient and cytoprotectant, zinc is involved in many types of apoptosis. Here, we studied the effects of zinc and ZIP1 on fluoride-induced apoptosis in mouse MC3T3-E1 cells and examined the underlying molecular mechanisms. Our study found that fluoride not only inhibited cell proliferation and increased the intracellular reactive oxygen species (ROS) but also induced cell apoptosis. Whereas pretreatment with zinc significantly attenuated fluoride-induced ROS production and partly protected cells against fluoride-induced apoptosis through MAPK/ERK signaling pathway. Our study also found that fluoride upregulated the expression of ZIP1 in a time-dependent manner. Moreover, overexpression of ZIP1 also inhibited fluoride-induced apoptosis by activation of PI3K/Akt pathway. This cytoprotective effect of zinc and ZIP1 may be new factors that affect the physiological activity of fluoride and need study further.

  20. Antibodies to Glycoproteins Shared by Human Peripheral Nerve and Campylobacter jejuni in Patients with Multifocal Motor Neuropathy

    Directory of Open Access Journals (Sweden)

    Ljubica Suturkova

    2013-01-01

    Full Text Available We have tested serum samples from 24 patients with multifocal motor neuropathy (MMN for reactivity to ganglioside GM1 and to Gal(β1–3GalNAc-bearing glycoproteins isolated from human peripheral nerve and from Campylobacter jejuni (Cj serotype O:19. IgM anti-GM1 antibodies were detected by ELISA in 11 patients (45.8% with MMN and in only one subject (4% from the control group. Western blots showed positive reactivity of sera from 6 patients (25% with MMN to several Gal(β1–3GalNAc-bearing glycoproteins from human peripheral nerve and from Cj O:19 isolates. Sera from three patients (12.5% with MMN showed positively reactive bands with similar electrophoretic mobility in all isolates (60–62 kDa, 48–51 kDa, 42 kDa, and 38 kDa. All six patients showed positive reactivity to 48–52 kDa protein isolated from human peripheral nerve. Increased titer of IgG antibodies to 60–62 kDa protein isolated from Cj O:19 associated with Guillain-Barré syndrome was detected in three patients, and their serum showed also IgG positive reactivity to peripheral nerve antigen with the same electrophoretic mobility. One of these patients had a previous history of Cj infection which suggests the possibility that Cj may be also involved in the pathogenesis of MMN.

  1. Identifying the differences in mechanisms of mycophenolic acid controlling fucose content of glycoproteins expressed in different CHO cell lines.

    Science.gov (United States)

    Zhang, An; Tsang, Valerie Liu; Markely, Lam R; Kurt, Lutfiye; Huang, Yao-Ming; Prajapati, Shashi; Kshirsagar, Rashmi

    2016-11-01

    In the biopharmaceutical industry, glycosylation is a critical quality attribute that can modulate the efficacy of a therapeutic glycoprotein. Obtaining a consistent glycoform profile is desired because molecular function can be defined by its carbohydrate structures. Specifically, the fucose content of oligosaccharides in glycoproteins is one of the most important attributes that can significantly affect antibody-dependent cellular cytotoxicity (ADCC) activity. It is therefore important to understand the fucosylation pathway and be able to control fucosylation at the desired level to match predecessor materials in late stage and biosimilar programs. Several strategies were explored in this study and mycophenolic acid (MPA) was able to finely modulate the fucose content with the least undesired side effects. However, the response was significantly different between CHO cell lines of different lineages. Further experiments were then performed for a deeper understanding of the mechanism of fucosylation in different CHO cell lines. Results indicated that changes in the intracellular nucleotide involved in fucosylation pathway after MPA treatment are the main cause of the differences in fucosylation level response in different CHO cell lines. Differences in MPA metabolism in the various CHO cell lines directly resulted in different levels of afucosylation measured in antibodies produced by the CHO cell lines. Biotechnol. Bioeng. 2016;113: 2367-2376. © 2016 Wiley Periodicals, Inc.

  2. Copper(II) interaction with peptide fragments of histidine-proline-rich glycoprotein: Speciation, stability and binding details.

    Science.gov (United States)

    La Mendola, Diego; Magrì, Antonio; Santoro, Anna Maria; Nicoletti, Vincenzo G; Rizzarelli, Enrico

    2012-06-01

    GHHPH is the peptide repeat present in histidine-proline rich glycoprotein (HPRG), a plasma glycoprotein involved in angiogenesis process. The copper(II) ions interaction with mono (Ac-GHHPHG-NH(2)) and its bis-repeat (Ac-GHHPHGHHPHG-NH(2)) was investigated by means of potentiometric and spectroscopic techniques. To single out the copper(II) coordination environments of different species formed with Ac-GHHPHG-NH(2), three single point mutated peptides were also synthesized and their ability to coordinate Cu(2+) investigated. Ac-GHHPHG-NH(2) binds Cu(2+) by the imidazole side chain and the amide nitrogen deprotonation that takes place towards the N-terminus. The bis-repeat is able to bind Cu(2+) more efficiently than Ac-GHHPHG-NH(2). This difference is not only due to the number of His residues in the sequence but also to the different binding sites. In fact, the comparison of the potentiometric and spectroscopic data of the copper(II) complexes with a bis-repeatPeg construct Ac-(GHHPHG)-Peg-(GHHPHG)-NH(2) and those of the metal complexes with Ac-HGHH-NH(2), indicates that the central HGHH amino acid sequence is the main copper(II) binding site.

  3. Definition of the domain boundaries is critical to the expression of the nucleotide-binding domains of P-glycoprotein.

    Science.gov (United States)

    Kerr, Ian D; Berridge, Georgina; Linton, Kenneth J; Higgins, Christopher F; Callaghan, Richard

    2003-11-01

    Heterologous expression of domains of eukaryotic proteins is frequently associated with formation of inclusion bodies, consisting of aggregated mis-folded protein. This phenomenon has proved a significant barrier to the characterization of domains of eukaryotic ATP binding cassette (ABC) transporters. We hypothesized that the solubility of heterologously expressed nucleotide binding domains (NBDs) of ABC transporters is dependent on the definition of the domain boundaries. In this paper we have defined a core NBD, and tested the effect of extensions to and deletions of this core domain on protein expression. Of 10 NBDs constructed, only one was expressed as a soluble protein in Escherichia coli, with expression of the remaining NBDs being associated with inclusion body formation. The soluble NBD protein we have obtained corresponds to residues 386-632 of P-glycoprotein and represents an optimally defined domain. The NBD has been isolated and purified to 95% homogeneity by a two-step purification protocol, involving affinity chromatography and gel filtration. Although showing no detectable ATP hydrolysis, the protein retains specific ATP binding and has a secondary structure compatible with X-ray crystallographic data on bacterial NBDs. We have interpreted our results in terms of homology models, which suggest that the N-terminal NBD of P-glycoprotein can be produced as a stable, correctly folded, isolate domain with judicious design of the expression construct.

  4. Clinical relevance of P-glycoprotein activity on peripheral blood mononuclear cells and polymorphonuclear neutrophils to methotrexate in systemic lupus erythematosus patients.

    Science.gov (United States)

    García-Carrasco, Mario; Mendoza-Pinto, Claudia; Macías-Díaz, Salvador; Etchegaray-Morales, Ivet; Méndez-Martínez, Socorro; Soto-Santillán, Pamela; Pérez-Romano, Beatriz; Jiménez-Herrera, Erick A; Guzmán-Ruiz, Omar; Ruiz-Argüelles, Alejandro

    2017-06-14

    To elucidate the relationship between P-glycoprotein activity on peripheral blood leukocytes of systemic lupus erythematosus (SLE) patients with lupus arthritis and the clinical response to methotrexate. An observational study was made in patients with SLE according to ACR criteria 1997 who had arthralgia and arthritis and received methotrexate for ≥3 months. Methotrexate responders and non-responders were compared according to the Clinical Disease Activity Index. Mononuclear cells and polymorphonuclear neutrophils were isolated from SLE patients and P-glycoprotein expression was measured using the relative fluorescence index and percentage of positive cells. The chi-square test was used to compare P-glycoprotein activity between responders and non-responders. Thirty-two patients with a mean age of 45.4 ± 10.7 years were included: 34.4% had a response to methotrexate and 65.6% did not. Mean relative fluorescence units of both mononuclear cells and polymorphonuclear neutrophils were significantly lower in patients with a good response (7.0 ± 4.3 vs. 9.6 ± 3.8; p = 0.041 and 4.2 ± 3.5 vs. 7.6 ± 4.0; p = 0.004). The prevalence of low fluorescence levels (P-glycoprotein activity of both mononuclear cells and polymorphonuclear neutrophils, was higher in methotrexate responders than in non-responders (27.3 vs. 4.8%; p = 0.10 and 81.8 vs. 23.8%; p = 0.003, respectively). In SLE patients with joint involvement treated with methotrexate, P-glycoprotein activity was higher in responders to methotrexate than in non-responders. Further studies are required to determine the mechanisms behind this finding and whether P-glycoprotein activity mediates alterations in methotrexate efficacy.

  5. Enrichment and identification of glycoproteins in human saliva using lectin magnetic bead arrays.

    Science.gov (United States)

    Caragata, Michael; Shah, Alok K; Schulz, Benjamin L; Hill, Michelle M; Punyadeera, Chamindie

    2016-03-15

    Aberrant glycosylation of proteins is a hallmark of tumorigenesis and could provide diagnostic value in cancer detection. Human saliva is an ideal source of glycoproteins due to the relatively high proportion of glycosylated proteins in the salivary proteome. Moreover, saliva collection is noninvasive and technically straightforward, and the sample collection and storage is relatively easy. Although differential glycosylation of proteins can be indicative of disease states, identification of differential glycosylation from clinical samples is not trivial. To facilitate salivary glycoprotein biomarker discovery, we optimized a method for differential glycoprotein enrichment from human saliva based on lectin magnetic bead arrays (saLeMBA). Selected lectins from distinct reactivity groups were used in the saLeMBA platform to enrich salivary glycoproteins from healthy volunteer saliva. The technical reproducibility of saLeMBA was analyzed with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify the glycosylated proteins enriched by each lectin. Our saLeMBA platform enabled robust glycoprotein enrichment in a glycoprotein- and lectin-specific manner consistent with known protein-specific glycan profiles. We demonstrated that saLeMBA is a reliable method to enrich and detect glycoproteins present in human saliva.

  6. Preparation of Concanavalin A-Chelating Magnetic Nanoparticles for Selective Enrichment of Glycoproteins.

    Science.gov (United States)

    Dong, Liping; Feng, Shun; Li, Shanshan; Song, Peipei; Wang, Jide

    2015-07-07

    In this work, a soft and nondestructive approach was developed to prepare concanavalin A-chelating magnetic nanoparticles (Con A-MNPs) for selective enrichment of glycoproteins. Ethylenediamine tetraacetic acid-modified-MNPs (EDTA-MNPs) were prepared by a one-pot chemical coprecipitation method first, and then, Cu(II) cations were used as bridge groups to immobilize Con A on EDTA-MNPs. The as-prepared absorbents with a mean diameter of 15 nm showed a strong magnetic response to an externally applied magnetic field. The results of thermogravimetric analysis showed the content of immobilized Con A was up to 28 wt %. For glycoprotein ovalbumin, the maximum capacity and equilibrium constant were 72.41 mg/g and 0.6035 L/mg, respectively. The as-prepared nanocomposites exhibited a remarkable selectivity for glycoproteins and can enrich glycoproteins specifically from a mixture of glycoprotein and nonglycoprotein even at a molar ratio of 1:600. It was also successfully applied for the enrichment of glycoproteins from real egg white samples. We expect that our finding will serve as a helpful template for others to design new adsorbents for enriching glycoproteins.

  7. Protective Role of α2HS-Glycoprotein in HBV-Associated Liver Failure

    Directory of Open Access Journals (Sweden)

    Xue-Gong Fan

    2011-06-01

    Full Text Available n this study, levels of plasma α2-Heremans-Schmid glycoprotein, serum tumor necrosis factor-α, serum liver function parameters and short-term mortality were measured in 100 hepatitis B patients. Release of interleukin-6 and tumor necrosis factor-α from the lipopolysaccharide-stimulated peripheral blood mononuclear cells in the presence/absence of spermine and α2-Heremans-Schmid glycoprotein were analyzed by enzyme-linked immunosorbent assay to determine the significance and potential mechanism of α2-Heremans-Schmid glycoprotein in hepatitis B virus-associated liver damage. Results showed that serum α2-Heremans-Schmid glycoprotein levels in acute-on-chronic liver failure patients were significantly lower than that in chronic hepatitis B patients or healthy controls (p < 0.05. A negative dependence between serum human α2-Heremans-Schmid glycoprotein and tumor necrosis factor-α levels was observed. Interleukin-6 and tumor necrosis factor-α levels in the lipopolysaccharide-induced peripheral blood mononuclear cell supernates were significantly reduced by spermine and/or α2-Heremans-Schmid glycoprotein. The latter two proteins jointly inhibited cytokine release. These observations suggest that plasma α2-Heremans-Schmid glycoprotein is an independent marker of liver damage and a prognostic indicator of hepatitis B virus chronicity. It may reduce liver inflammation by partially inhibiting release of inflammatory factors from activated peripheral blood mononuclear cells.

  8. A regulatory variant in CYP2E1 affects the risk of lung squamous cell carcinoma.

    Science.gov (United States)

    Cao, Lei; Lin, Jia; He, Bing; Wang, Hongge; Rao, Juan; Liu, Yingwen; Zhang, Xuemei

    2014-01-01

    Cytochrome P450 2E1 (CYP2E1), an ethanol-inducible enzyme, has been shown to metabolically activate various carcinogens, which is critical for the development of cancers. It has been demonstrated that CYP2E1 polymorphisms alter the transcriptional activity. However, studies on the association between CYP2E1 -1239G>C polymorphism and non-small cell lung cancer have reported conflicting results. Thus, the gain of the present study was to investigate whether CYP2E1 -1239G>C polymorphism is associated with the development of non-small cell lung cancer in Chinese population. A case-control study was conducted in which CYP2E1 -1239G>C polymorphism was analyzed in 526 Chinese patients with non-small cell lung cancer and 526 age-matched healthy controls by polymerase chain reaction-restriction fragment length polymorphism. Odds ratios were estimated by multivariate logistic regression. A meta-analysis was conducted to evaluate the association of CYP2E1 -1239G>C polymorphism with the risk of lung cancer in Chinese population by calculating pooled odds ratio (OR). For CYP2E1 -1239G>C polymorphism, -1239C allele carriers (OR = 0.67; 95% confidence interval (CI) = 0.51-0.87; P = 0.002) were associated with a decreased risk of non-small cell lung cancer when compared with -1239GG homozygotes. In the group analyses by pathological types, for lung squamous cell carcinoma and other types, the ORs of the C allele carriers were 0.60 (95% CI = 0.41-0.88; P = 0.009) and 0.54 (95% CI = 0.30-0.99; P = 0.045). In the group analysis of smoking status, the OR for the -1239C allele-containing genotype was higher than that for -1239GG genotype (OR = 0.57; 95% CI = 0.40-0.81; P = 0.002) among smokers, but not among nonsmokers. Moreover, when the risk associated with CYP2E1 polymorphism was further evaluated within strata of C polymorphism and the risk of non-small cell lung cancer. Meta-analysis data also showed that the carriers of CYP2E1 -1239C allele

  9. Effects of pronase and neuraminidase treatment on a myelin-associated glycoprotein in developing brain.

    Science.gov (United States)

    Quarles, R H

    1976-04-15

    Rats (14 days old) were injected with [14c]fucose and young adult rats with [3H]fucose in order to label the myelin-associated glycoproteins. As previously reported, the major [14C]fucose-labelled glycoprotein in the immature myelin had a higher apparent molecular weight on sodium dodecyl sulphate/polyacrylamide gels that the [3H]fucose-labelled glycoprotein in mature myelin. This predominant doubly labelled glycoprotein component was partially purified by preparative gel electrophoresis and converted to glycopeptides by extensive Pronase digestion. Gel filtration on Sephadex G-50 separated the glycopeptides into several clases, which were designted A,B, C AND D, from high to low molecular weight. The 14C-labelled glycopeptides from immature myeline were enriched in the highest-molecular-weight class A relative to the 3H-labelled glycopeptides from mature myelin. Neuraminidase treatment of the glycoprotein before Pronase digestion greatly decreased the proportion of glycopeptides fractionating in the higher-molecular-weight classes and largely eliminated the developmental differences that were apparent by gel filtration. However, neuraminidase treatment did not decrease the magnitude of the developmental difference revealed by electrophoresing the intact glycoprotein on sodium dodecyl sulphate gels, although it did decrease the apparent molecular weight of the glycoprotein from both the 15-day-old and adult rats by an amount comparable in magnitude to that developmental difference. The results from gel filtration of glycopeptides indicate that there is a higher content of large molecular weight, sialic acid-rich oligosaccharide units in the glycoprotein of immature myelin. However, the higher apparent molecular weight for the glycoprotein from 15-day-old rats on sodium dodcyl sulphate gels is not due primarily to its higher sialic acid content.

  10. Bioactivity of proteins isolated from Lactobacillus plantarum L67 treated with Zanthoxylum piperitum DC glycoprotein.

    Science.gov (United States)

    Song, S; Oh, S; Lim, K-T

    2015-06-01

    Lactobacilli in the human gastrointestinal tract have beneficial effects on the health of their host. To enhance these effects, the bioactivity of lactobacilli can be fortified through exogenous dietary or pharmacological agents, such as glycoproteins. To elucidate the inductive effect of Zanthoxylum piperitum DC (ZPDC) glycoprotein on Lactobacillus plantarum L67, we evaluated the radical-scavenging activity, anti-oxidative enzymes (SOD, GPx and CAT), growth rate, ATPase activity and β-galactosidase activity of this strain. When Lact. plantarum L67 was treated with ZPDC glycoprotein at different concentrations, the intensities of a few SDS-PAGE bands were slightly changed. The amount of a 23 kDa protein was increased upon treatment with increasing concentrations of ZPDC glycoprotein. The results of this study indicate that the radical-scavenging activity for O2(-) and OH¯, but not for the DPPH radical, increased in a concentration-dependent manner after treatment with ZPDC glycoprotein. The activation of anti-oxidative enzymes (SOD, GPx and CAT), growth rate and β-galactosidase activity also increased in a concentration-dependent manner in response to ZPDC glycoprotein treatment, whereas ATPase activity was decreased. In summary, ZPDC glycoprotein stimulated an increase in the bioactivity of Lact. plantarum L67. Significance and impact of the study: This study demonstrated that Lactobacillus plantarum L67 possesses anti-oxidative activity. This strain of lactic bacteria has been known to have various probiotic uses, such as yogurt starters and dietary additional supplements. We found, through this experiment, that the protein has a strong anti-oxidative character, and the activity can be enhanced by treatment with Zanthoxylum piperitum DC (ZPDC) glycoprotein. This study may be application of Lact. plantarum L67 treated by ZPDC glycoprotein in yogurt fermentation. It could be one of the avenues of minimizing yogurt postacidification during storage. In addition

  11. Recombinant E2 glycoprotein of bovine viral diarrhea virus induces a solid humoral neutralizing immune response but fails to confer total protection in cattle

    Directory of Open Access Journals (Sweden)

    S. Chimeno Zoth

    2007-06-01

    Full Text Available Two recombinant baculoviruses were produced in order to obtain a bovine viral diarrhea virus (BVDV immunogen: AcNPV/E2 expressing E2 glycoprotein, and AcNPV/E0E1E2 expressing the polyprotein region coding for the three structural proteins of BVDV (E0, E1, and E2. Mice were immunized with Sf9 cells infected with the recombinant baculoviruses in a water in oil formulation and the production of neutralizing antibodies was evaluated. Since E2 elicited higher neutralizing antibody titers than E0-E1-E2 polyprotein, it was selected to immunize cattle. Calves received two doses of recombinant E2 vaccine and were challenged with homologous BVDV 37 days later. The recombinant immunogen induced neutralizing titers which showed a mean value of 1.5 ± 0.27 on the day of challenge and reached a top value of 3.36 ± 0.36, 47 days later (84 days post-vaccination. On the other hand, sera from animals which received mock-infected Sf9 cells did not show neutralizing activity until 25 days post-challenge (62 days post-vaccination, suggesting that these antibodies were produced as a consequence of BVDV challenge. Even when no total protection was observed in cattle, in vitro viral neutralization assays revealed that the recombinant immunogen was able to induce neutralizing antibody synthesis against the homologous strain as well as against heterologous strains in a very efficient way.

  12. Varicella-zoster virus glycoprotein I is essential for growth of virus in Vero cells.

    OpenAIRE

    Cohen, J I; Nguyen, H.

    1997-01-01

    Varicella-zoster virus (VZV) encodes at least six glycoproteins. Glycoprotein I (gI), the product of open reading frame 67, is a 58- to 62-kDa glycoprotein found in VZV-infected cells. We constructed two VZV gI deletion mutants. Immunoprecipitation of VZV gE from infected cells indicated that cells infected with VZV deleted for gI expressed a gE that was larger (100 kDa) than that expressed in cells infected with the parental virus (98 kDa). Cell-associated or cell-free VZV deleted for gI gre...

  13. THE ROLE OF P-GLYCOPROTEIN IN RATIONAL PHARMACOTHERAPY IN CARDIOLOGY

    Directory of Open Access Journals (Sweden)

    A. V. Shulkin

    2015-09-01

    Full Text Available On the basis of the analysis of published data the role of P-glycoprotein, carrier protein, in rational pharmacotherapy in cardiology was shown on the example of its substrates – digoxin, antiplatelet agents and anticoagulants. Determination of C3435T polymorphism of multidrug resistance gene (MDR1, encoding P-glycoprotein, in pharmacotherapy with digoxin, antiplatelet drugs (clopidogrel tikagrelol, prasugrel and anticoagulants (dabigatran etexilate, rivaroxaban, edoxaban is not feasible in routine practice. Drug in- teractions have clinical implications for the efficacy and safety of pharmacotherapy in coadministration of these drugs with P-glycoprotein substrates, inducers and inhibitors.

  14. THE ROLE OF P-GLYCOPROTEIN IN RATIONAL PHARMACOTHERAPY IN CARDIOLOGY

    Directory of Open Access Journals (Sweden)

    A. V. Shulkin

    2013-01-01

    Full Text Available On the basis of the analysis of published data the role of P-glycoprotein, carrier protein, in rational pharmacotherapy in cardiology was shown on the example of its substrates – digoxin, antiplatelet agents and anticoagulants. Determination of C3435T polymorphism of multidrug resistance gene (MDR1, encoding P-glycoprotein, in pharmacotherapy with digoxin, antiplatelet drugs (clopidogrel tikagrelol, prasugrel and anticoagulants (dabigatran etexilate, rivaroxaban, edoxaban is not feasible in routine practice. Drug in- teractions have clinical implications for the efficacy and safety of pharmacotherapy in coadministration of these drugs with P-glycoprotein substrates, inducers and inhibitors.

  15. Identification of the milk fat globule membrane proteins. I. Isolation and partial characterization of glycoprotein B.

    Science.gov (United States)

    Basch, J J; Farrell, H M; Greenberg, R

    1976-11-02

    The salt soluble proteins from the fat globule membrane of cow's milk were resolved into three fractions by Sephadex column chromatography in sodium dodecyl sulfate. One of the fractions, termed glycoprotein B, was purified by rechromatography to essentially one band on sodium dodecyl sulfate gel electrophoresis. It was found to contain 14% carbohydrate including sialic acid, mannose, galactose, glucose, glucosamine and galactosamine. The amino acid composition of glycoprotein B was determined; it has amino terminal serine and carboxyl terminal leucine. The molecular weight of this glycoprotein as estimated by sodium dodecyl sulfate gel electrophoresis is 49 500.

  16. Absence of mutations in NR2E1 and SNX3 in five patients with MMEP (microcephaly, microphthalmia, ectrodactyly, and prognathism and related phenotypes

    Directory of Open Access Journals (Sweden)

    Simpson Elizabeth M

    2007-07-01

    Full Text Available Abstract Background A disruption of sorting nexin 3 (SNX3 on 6q21 was previously reported in a patient with MMEP (microcephaly, microphthalmia, ectrodactyly, and prognathism and t(6;13(q21;q12 but no SNX3 mutations were identified in another sporadic case of MMEP, suggesting involvement of another gene. In this work, SNX3 was sequenced in three patients not previously studied for this gene. In addition, we test the hypothesis that mutations in the neighbouring gene NR2E1 may underlie MMEP and related phenotypes. Methods Mutation screening was performed in five patients: the t(6;13(q21;q12 MMEP patient, three additional patients with possible MMEP or a related phenotype, and one patient with oligodactyly, ulnar aplasia, and a t(6;7(q21;q31.2 translocation. We used sequencing to exclude SNX3 coding mutations in three patients not previously studied for this gene. To test the hypothesis that mutations in NR2E1 may contribute to MMEP or related phenotypes, we sequenced the entire coding region, complete 5' and 3' untranslated regions, consensus splice-sites, and evolutionarily conserved regions including core and proximal promoter in all five patients. Two-hundred and fifty control subjects were genotyped for any candidate mutation. Results We did not detect any synonymous nor nonsynonymous coding mutations of NR2E1 or SNX3. In one patient with possible MMEP, we identified a candidate regulatory mutation that has been reported previously in a patient with microcephaly but was not found in 250 control subjects examined here. Conclusion Our results do not support involvement of coding mutations in NR2E1 or SNX3 in MMEP or related phenotypes; however, we cannot exclude the possibility that regulatory NR2E1 or SNX3 mutations or deletions at this locus may underlie abnormal human cortical development in some patients.

  17. PDH-E1alpha dephosphorylation and activation in human skeletal muscle during exercise

    DEFF Research Database (Denmark)

    Pilegaard, Henriette; Birk, Jesper Bratz; Sacchetti, Massimo;

    2006-01-01

    extensor exercise at moderate intensity. During the 4-h resting period, activity of PDH in the active form (PDHa) did not change in either trial, yet phosphorylation of PDH-E1a site 1 (PDH-P1) and site 2 (PDH-P2) was elevated in the intralipid compared with the control trial. PDHa activity increased during...

  18. US NDC Modernization Iteration E1 Prototyping Report: User Interface Framework

    Energy Technology Data Exchange (ETDEWEB)

    Lober, Randall R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-12-01

    During the first iteration of the US NDC Modernization Elaboration phase (E1), the SNL US NDC modernization project team completed an initial survey of applicable COTS solutions, and established exploratory prototyping related to the User Interface Framework (UIF) in support of system architecture definition. This report summarizes these activities and discusses planned follow-on work.

  19. 26 CFR 301.6511(e)-1 - Special rules applicable to manufactured sugar.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Special rules applicable to manufactured sugar... Assessment and Collection § 301.6511(e)-1 Special rules applicable to manufactured sugar. (a) Use as... the person entitled thereto. Such right accrues as of the date the manufactured sugar, or article...

  20. US NDC Modernization Iteration E1 Prototyping Report: Processing Control Framework

    Energy Technology Data Exchange (ETDEWEB)

    Prescott, Ryan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hamlet, Benjamin R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-12-01

    During the first iteration of the US NDC Modernization Elaboration phase (E1), the SNL US NDC modernization project team developed an initial survey of applicable COTS solutions, and established exploratory prototyping related to the processing control framework in support of system architecture definition. This report summarizes these activities and discusses planned follow-on work.

  1. US NDC Modernization Iteration E1 Prototyping Report: Common Object Interface

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Jennifer E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hess, Michael M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-12-01

    During the first iteration of the US NDC Modernization Elaboration phase (E1), the SNL US NDC modernization project team completed an initial survey of applicable COTS solutions, and established exploratory prototyping related to the Common Object Interface (COI) in support of system architecture definition. This report summarizes these activities and discusses planned follow-on work.

  2. Transcriptional activation by the E1A regions of adenovirus types 40 and 41

    NARCIS (Netherlands)

    Loon, A.E. van; Gilardi, P.; Perricaudet, M.; Rozijn, Th. H.; Sussenbach, J.S.

    1987-01-01

    In order to establish whether the poor growth of the two fastidious adenoviruses types 40 and 41 (Ad40 and Ad41) in HeLa cells is due to a reduced trans-activation by the early region to (E1A), we have determined the trans-activating effect of this region on the expression of the chloramphenicol ace

  3. Two-step method for curing Escherichia coli of ColE1-derived plasmids

    DEFF Research Database (Denmark)

    Hove-Jensen, Bjarne

    2008-01-01

    To cure Escherichia coli for plasmids derived from the ColE1 replicon advantage is taken of the fact that maintenance of this replicon requires a wild-type allele of polA, encoding DNA polymerase I. Curing is achieved by cotransduction of a mutant polA allele with metE::Tn10, fadAB::Tn10 or other...

  4. Crystal structure of the Epstein-Barr virus (EBV) glycoprotein H/glycoprotein L (gH/gL) complex.

    Science.gov (United States)

    Matsuura, Hisae; Kirschner, Austin N; Longnecker, Richard; Jardetzky, Theodore S

    2010-12-28

    The Epstein-Barr virus (EBV) is a γ-herpesvirus that infects B cells and epithelial cells and that has been linked to malignancies in both cell types in vivo. EBV, like other herpesviruses, has three glycoproteins, glycoprotein B (gB), gH, and gL, that form the core membrane fusion machinery mediating viral penetration into the cell. The gH and gL proteins associate to form a heterodimeric complex, which is necessary for efficient membrane fusion and also implicated in direct binding to epithelial cell receptors required for viral entry. To gain insight into the mechanistic role of gH/gL, we determined the crystal structure of the EBV gH/gL complex. The structure is comprised of four domains organized along the longest axis of the molecule. Comparisons with homologous HSV-2 gH/gL and partial pseudorabies virus gH structures support the domain boundaries determined for the EBV gH/gL structure and illustrate significant differences in interdomain packing angles. The gL subunit and N-terminal residues of gH form a globular domain at one end of the structure, implicated in interactions with gB and activation of membrane fusion. The C-terminal domain of gH, proximal to the viral membrane, is also implicated in membrane fusion. The gH/gL structure locates an integrin binding motif, implicated in epithelial cell entry, on a prominent loop in the central region of the structure. Multiple regions of gH/gL, including its two extreme ends, are functionally important, consistent with the multiple roles of gH/gL in EBV entry.

  5. Osteogenic gene expression of murine osteoblastic (MC3T3-E1) cells under cyclic tension

    Science.gov (United States)

    Kao, C. T.; Chen, C. C.; Cheong, U.-I.; Liu, S. L.; Huang, T. H.

    2014-08-01

    Low-level laser therapy (LLLT) can promote cell proliferation. The remodeling ability of the tension side of orthodontic teeth affects post-orthodontic stability. The purpose of the present study was to investigate the osteogenic effects of LLLT on osteoblast-like cells treated with a simulated tension system that provides a mechanical tension regimen. Murine osteoblastic (MC3T3-E1) cells were cultured in a Flexcell strain unit with programmed loads of 12% elongation at a frequency of 0.5 Hz for 24 and 48 h. The cultured cells were treated with a low-level diode laser using powers of 5 J and 10 J. The proliferation of MC3T3-E1 cells was determined using the Alamar Blue assay. The expression of osteogenic genes (type I collagen (Col-1), osteopontin (OPN), osteocalcin (OC), osteoprotegerin (OPG), receptor activator of nuclear factor kappa B ligand (RANKL), bone morphologic protein (BMP-2), and bone morphologic protein (BMP-4)) in MC3T3-E1 cells was analyzed using reverse transcription polymerase chain reaction (RT-PCR). The data were analyzed using one-way analysis of variance. The proliferation rate of tension-cultured MC3T3-E1 cells under 5 J and 10 J LLLT increased compared with that of the control group (p < 0.05). Prominent mineralization of the MC3T3-E1 cells was visible using a von Kossa stain in the 5 J LLLT group. Osteogenic genes (Col-1, OC, OPG and BMP-2) were significantly expressed in the MC3T3-E1 cells treated with 5 J and 10 J LLLT (p < 0.05). LLLT in tension-cultured MC3T3-E1 cells showed synergistic osteogenic effects, including increases in cell proliferation and Col-1, OPN, OC, OPG and BMP-2 gene expression. LLLT might be beneficial for bone remodeling on the tension side of orthodontics.

  6. E1A,E1B double-restricted adenovirus enhances the cytotoxicity and antitumor activity of gemcitabine to renal cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    WANG Hua; Makoto Satoh; CHEN Gui-ping; LI De-chuan; Hirofumi Hamada; Yoichi Arai

    2011-01-01

    Background Our previous studies have demonstrated potent oncolysis efficacy of the E1A,E1B double-restricted replication-competent oncolytic adenovirus AxdAdB-3 for treatment of bladder cancer. Here,we reported the feasibility and efficacy of AxdAdB-3 alone,or in combination with gemcitabine for treating renal cell carcinoma.Methods Cytopathic effects of AxdAdB-3 were evaluated in human renal cell carcinoma cell lines TOS-1,TOS-2,TOS-3,TOS-3LN,SMKT-R3,SMKT-R4 and ACHN,and in normal human renal proximal tubule epithelial cells (RPTEC).AxdAdB-3 induced down-regulation of the cell cycle was determined by flow cytometry. Combination therapies of AxdAdB-3 with gemcitabine were evaluated in vitro and in vivo on subcutaneous TOS-3LN tumors in a severe combined immunodeficiency disease (SCID) mouse model.Results AxdAdB-3 was potently cytopathic against the tested most renal cell carcinoma cell lines including TOS-2,TOS-3,TOS-3LN,SMKT-R3 and SMKT-R4,while normal human RPTEC were not destroyed. AxdAdB-3 effectively induced cell cycle S-phase entry. Combined therapy of AxdAdB-3 with gemcitabine demonstrated stronger antitumor effects in vitro and in vivo compared with either AxdAdB-3 or gemcitabine alone.Conclusion AxdAdB-3 alone,or in combination with gemcitabine may be a promising strategy against renal cell carcinoma.

  7. The development of the CHANG'`E-1 lunar explorer laser altimeter

    Science.gov (United States)

    Shu, R.; Wang, J. Y.; Hu, Y. H.; Jia, J. J.

    According to Chinese fable CHANG prime E is the name of a peri who lives in the moon with a white rabbit The CHANG prime E-1 lunar explorer will be launched in April 2007 The Lunar Explorer Laser Altimeter LELA is one of the 6 payloads in Chang prime E-1 which is developed by Shanghai Institute of Technical Physics Chinese Academy of Sciences The data of LELA will be used with the Optical Imager for acquiring the three dimension image of the moon surface The LELA transmits laser pulses determines their round trip times to the surface of the moon using a time interval counter and measures ranges between CHANG prime E-1 lunar explorer and the lunar surface in the nadir direction with 5m accuracy every 1 second for 1 year s mission period The acquired range data are transformed to the topography of the moon with the aid of position and attitude data of the CHANG prime E-1 lunar explorer obtained from the ground-based tracking and on board star sensor respectively The mean distances between Chang prime E-1 and the surface of moon is 200Km The LELA utilizes a laser diode LD pumped Q-switched Nd YAG laser that has a wavelength of 1064nm a pulse width of 10ns The output beam divergence is improved to 0 6mrad by Galileo refractor-type collimator which resulted in a moon surface spot size foot print of 120m The return pulses are captured by Cassegrain-type reflector and detected by Si-APD detector The prototype began from 2003 Until now the engineering model had been finished

  8. AglJ adds the first sugar of the N-linked pentasaccharide decorating the Haloferax volcanii S-layer glycoprotein.

    Science.gov (United States)

    Kaminski, Lina; Abu-Qarn, Mehtap; Guan, Ziqiang; Naparstek, Shai; Ventura, Valeria V; Raetz, Christian R H; Hitchen, Paul G; Dell, Anne; Eichler, Jerry

    2010-11-01

    Like the Eukarya and Bacteria, the Archaea also perform N glycosylation. Using the haloarchaeon Haloferax volcanii as a model system, a series of Agl proteins involved in the archaeal version of this posttranslational modification has been identified. In the present study, the participation of HVO_1517 in N glycosylation was considered, given its homology to a known component of the eukaryal N-glycosylation pathway and because of the genomic proximity of HVO_1517 to agl genes encoding known elements of the H. volcanii N-glycosylation process. By combining the deletion of HVO_1517 with mass spectrometric analysis of both dolichol phosphate monosaccharide-charged carriers and the S-layer glycoprotein, evidence was obtained showing the participation of HVO_1517, renamed AglJ, in adding the first hexose of the N-linked pentasaccharide decorating this reporter glycoprotein. The deletion of aglJ, however, did not fully prevent the attachment of a hexose residue to the S-layer glycoprotein. Moreover, in the absence of AglJ, the level of only one of the three monosaccharide-charged dolichol phosphate carriers detected in the cell was reduced. Nonetheless, in cells lacking AglJ, no further sugar subunits were added to the remaining monosaccharide-charged dolichol phosphate carriers or to the monosaccharide-modified S-layer glycoprotein, pointing to the importance of the sugar added through the actions of AglJ for proper N glycosylation. Finally, while aglJ can be deleted, H. volcanii surface layer integrity is compromised in the absence of the encoded protein.

  9. Capillary electrophoresis-electrospray ionization mass spectrometry for rapid and sensitive N-glycan analysis of glycoproteins as 9-fluorenylmethyl derivatives.

    Science.gov (United States)

    Nakano, Miyako; Higo, Daisuke; Arai, Etsuo; Nakagawa, Takatoshi; Kakehi, Kazuaki; Taniguchi, Naoyuki; Kondo, Akihiro

    2009-02-01

    It is well known that most protein therapeutics such as monoclonal antibody pharmaceuticals and other biopharmaceuticals including cancer biomarkers are glycoproteins, and thus the development of high-throughput and sensitive analytical methods for glycans is essential in terms of their determination and quality control. We previously reported a novel alternative labeling method for glycans involving 9-fluorenylmethyl chloroformate (Fmoc-Cl) instead of the conventional reductive amination procedure. The derivatives were analyzed by high-performance liquid chromatography (HPLC) (Kamoda S, Nakano M, Ishikawa R, Suzuki S, Kakehi K. 2005. Rapid and sensitive screening of N-glycans as 9-fluorenylmethyl derivatives by high-performance liquid chromatography: A method which can recover free oligosaccharides after analysis. J Proteome Res. 4:146-152). This method was rapid and simple; however, it was time-consuming in terms of analysis by HPLC and did not provide so much information such as the detailed structures and mass numbers of glycans. Here we have developed a high-throughput and highly sensitive method. It comprises three steps, i.e., release of glycans, derivatization with Fmoc, and capillary electrophoresis-electrospray ionization mass spectrometry (CE-ESI MS) analysis. We analyzed several glycoproteins such as fetuin, alpha1 acid glycoprotein, IgG, and transferrin in order to validate this method. We were able to analyze the above glycoproteins with the three-step procedure within only 5 h, which provided detailed N-glycan patterns. Moreover, the MS/MS analysis allowed identification of the N-glycan structures. As novel applications, the method was employed for the analysis of N-glycans derived from monoclonal antibody pharmaceuticals and also from alpha-fetoprotein; the latter is known as one of the tumor markers of hepatocellular carcinomas. We were able to easily and rapidly determine the detailed structures of the N-glycans. The present method is very useful

  10. Elite suppressor-derived HIV-1 envelope glycoproteins exhibit reduced entry efficiency and kinetics.

    Science.gov (United States)

    Lassen, Kara G; Lobritz, Michael A; Bailey, Justin R; Johnston, Samantha; Nguyen, Sandra; Lee, Benhur; Chou, Tom; Siliciano, Robert F; Markowitz, Martin; Arts, Eric J

    2009-04-01

    Elite suppressors (ES) are a rare subset of HIV-1-infected individuals who are able to maintain HIV-1 viral loads below the limit of detection by ultra-sensitive clinical assays in the absence of antiretroviral therapy. Mechanism(s) responsible for this elite control are poorly understood but likely involve both host and viral factors. This study assesses ES plasma-derived envelope glycoprotein (env) fitness as a function of entry efficiency as a possible contributor to viral suppression. Fitness of virus entry was first evaluated using a novel inducible cell line with controlled surface expression levels of CD4 (receptor) and CCR5 (co-receptor). In the context of physiologic CCR5 and CD4 surface densities, ES envs exhibited significantly decreased entry efficiency relative to chronically infected viremic progressors. ES envs also demonstrated slow entry kinetics indicating the presence of virus with reduced entry fitness. Overall, ES env clones were less efficient at mediating entry than chronic progressor envs. Interestingly, acute infection envs exhibited an intermediate phenotypic pattern not distinctly different from ES or chronic progressor envs. These results imply that lower env fitness may be established early and may directly contribute to viral suppression in ES individuals.

  11. Elite suppressor-derived HIV-1 envelope glycoproteins exhibit reduced entry efficiency and kinetics.

    Directory of Open Access Journals (Sweden)

    Kara G Lassen

    2009-04-01

    Full Text Available Elite suppressors (ES are a rare subset of HIV-1-infected individuals who are able to maintain HIV-1 viral loads below the limit of detection by ultra-sensitive clinical assays in the absence of antiretroviral therapy. Mechanism(s responsible for this elite control are poorly understood but likely involve both host and viral factors. This study assesses ES plasma-derived envelope glycoprotein (env fitness as a function of entry efficiency as a possible contributor to viral suppression. Fitness of virus entry was first evaluated using a novel inducible cell line with controlled surface expression levels of CD4 (receptor and CCR5 (co-receptor. In the context of physiologic CCR5 and CD4 surface densities, ES envs exhibited significantly decreased entry efficiency relative to chronically infected viremic progressors. ES envs also demonstrated slow entry kinetics indicating the presence of virus with reduced entry fitness. Overall, ES env clones were less efficient at mediating entry than chronic progressor envs. Interestingly, acute infection envs exhibited an intermediate phenotypic pattern not distinctly different from ES or chronic progressor envs. These results imply that lower env fitness may be established early and may directly contribute to viral suppression in ES individuals.

  12. Evaluation of P-glycoprotein (Pgp) expression in human osteosarcoma by high-throughput tissue microarray.

    Science.gov (United States)

    Gao, Yan; Liao, Yunfei; Shen, Jacson K; Feng, Yong; Choy, Edwin; Cote, Gregory; Harmon, David; Mankin, Henry J; Hornicek, Francis J; Duan, Zhenfeng

    2016-09-01

    Survival of osteosarcoma patients is currently limited by the development of metastases and multidrug resistance (MDR). A well-established cause of MDR involves overexpression of P-glycoprotein (Pgp) in tumor cells. However, some discrepancies still exist as to the clinical significance of Pgp in osteosarcoma. We sought to elucidate further whether the Pgp expression correlated with clinical behavior in a series of patients with osteosarcoma via high-throughput tissue microarray (TMA) analysis. Immunohistochemical analysis of Pgp expression in a TMA of 114 specimens with a retrospective review of 70 osteosarcoma patients admitted to the Massachusetts General Hospital (MGH) was performed. High Pgp expression was correlated with metastasis development and poor response to pre-operative chemotherapy in osteosarcoma patients. Eighteen of the fifty-seven patients initially admitted with primary osteosarcoma showed high Pgp expression. Among these 18 patients with high Pgp expression, 13 of 18 (72%) patients eventually developed metastases. There was no significant clinical relevance between Pgp expression and osteosarcoma survival. These results support that high expression of Pgp is important, but cannot be assigned as, an individual predictor in the development of human osteosarcoma. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1606-1612, 2016. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  13. Endomorphins, Met-enkephalin, Tyr-MIF-1, and the P-glycoprotein efflux system.

    Science.gov (United States)

    Kastin, Abba J; Fasold, Melita B; Zadina, James E

    2002-03-01

    The P-glycoprotein (P-gp) transport system, responsible for the efflux of many therapeutic drugs out of the brain, recently has been shown to transport the endogenous brain opiate endorphin. We used P-gp knockout mice (Mdr1a) and their controls to determine where P-gp is involved in the saturable efflux systems of four other endogenous opiate-modulating peptides across the blood-brain barrier (BBB). After injection of endomorphin-1 (Tyr-Pro-Trp-Phe-NH(2)), endomorphin-2 (Tyr-Pro-Phe-Phe-NH(2)), Met-enkephalin (Tyr-Gly-Gly-Phe-Met-OH), and Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH(2)) into the lateral ventricle of the mouse brain, residual radioactivity was measured at 0, 2, 5, 10, and 20 min later. The results showed no difference in the disappearance of any of these peptides from the brains of knockout mice compared with their controls. This demonstrates that unlike endorphin and morphine, P-gp does not seem to be required for the brain-to-blood transport of the endomorphins, Met-enkephalin, or Tyr-MIF-1 across the BBB.

  14. A Method for Comprehensive Glycosite-Mapping and Direct Quantitation of Serum Glycoproteins.

    Science.gov (United States)

    Hong, Qiuting; Ruhaak, L Renee; Stroble, Carol; Parker, Evan; Huang, Jincui; Maverakis, Emanual; Lebrilla, Carlito B

    2015-12-04

    A comprehensive glycan map was constructed for the top eight abundant glycoproteins in plasma using both specific and nonspecific enzyme digestions followed by nano liquid chromatography (LC)-chip/quadrupole time-of-flight mass spectrometry (MS) analysis. Glycopeptides were identified using an in-house software tool, GPFinder. A sensitive and reproducible multiple reaction monitoring (MRM) technique on a triple quadrupole MS was developed and applied to quantify immunoglobulins G, A, M, and their site-specific glycans simultaneously and directly from human serum/plasma without protein enrichments. A total of 64 glycopeptides and 15 peptides were monitored for IgG, IgA, and IgM in a 20 min ultra high performance (UP)LC gradient. The absolute protein contents were quantified using peptide calibration curves. The glycopeptide ion abundances were normalized to the respective protein abundances to separate protein glycosylation from protein expression. This technique yields higher method reproducibility and less sample loss when compared with the quantitation method that involves protein enrichments. The absolute protein quantitation has a wide linear range (3-4 orders of magnitude) and low limit of quantitation (femtomole level). This rapid and robust quantitation technique, which provides quantitative information for both proteins and glycosylation, will further facilitate disease biomarker discoveries.

  15. Drug transport mechanism of P-glycoprotein monitored by single molecule fluorescence resonance energy transfer

    Science.gov (United States)

    Ernst, S.; Verhalen, B.; Zarrabi, N.; Wilkens, S.; Börsch, M.

    2011-03-01

    In this work we monitor the catalytic mechanism of P-glycoprotein (Pgp) using single-molecule fluorescence resonance energy transfer (FRET). Pgp, a member of the ATP binding cassette family of transport proteins, is found in the plasma membrane of animal cells where it is involved in the ATP hydrolysis driven export of hydrophobic molecules. When expressed in the plasma membrane of cancer cells, the transport activity of Pgp can lead to the failure of chemotherapy by excluding the mostly hydrophobic drugs from the interior of the cell. Despite ongoing effort, the catalytic mechanism by which Pgp couples MgATP binding and hydrolysis to translocation of drug molecules across the lipid bilayer is poorly understood. Using site directed mutagenesis, we have introduced cysteine residues for fluorescence labeling into different regions of the nucleotide binding domains (NBDs) of Pgp. Double-labeled single Pgp molecules showed fluctuating FRET efficiencies during drug stimulated ATP hydrolysis suggesting that the NBDs undergo significant movements during catalysis. Duty cycle-optimized alternating laser excitation (DCO-ALEX) is applied to minimize FRET artifacts and to select the appropriate molecules. The data show that Pgp is a highly dynamic enzyme that appears to fluctuate between at least two major conformations during steady state turnover.

  16. The secreted glycoprotein lubricin protects cartilage surfaces and inhibits synovial cell overgrowth

    Science.gov (United States)

    Rhee, David K.; Marcelino, Jose; Baker, MacArthur; Gong, Yaoqin; Smits, Patrick; Lefebvre, Véronique; Jay, Gregory D.; Stewart, Matthew; Wang, Hongwei; Warman, Matthew L.; Carpten, John D.

    2005-01-01

    The long-term integrity of an articulating joint is dependent upon the nourishment of its cartilage component and the protection of the cartilage surface from friction-induced wear. Loss-of-function mutations in lubricin (a secreted glycoprotein encoded by the gene PRG4) cause the human autosomal recessive disorder camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP). A major feature of CACP is precocious joint failure. In order to delineate the mechanism by which lubricin protects joints, we studied the expression of Prg4 mRNA during mouse joint development, and we created lubricin-mutant mice. Prg4 began to be expressed in surface chondrocytes and synoviocytes after joint cavitation had occurred and remained strongly expressed by these cells postnatally. Mice lacking lubricin were viable and fertile. In the newborn period, their joints appeared normal. As the mice aged, we observed abnormal protein deposits on the cartilage surface and disappearance of underlying superficial zone chondrocytes. In addition to cartilage surface changes and subsequent cartilage deterioration, intimal cells in the synovium surrounding the joint space became hyperplastic, which further contributed to joint failure. Purified or recombinant lubricin inhibited the growth of these synoviocytes in vitro. Tendon and tendon sheath involvement was present in the ankle joints, where morphologic changes and abnormal calcification of these structures were observed. We conclude that lubricin has multiple functions in articulating joints and tendons that include the protection of surfaces and the control of synovial cell growth. PMID:15719068

  17. Inhibitory Effects of Daiokanzoto (Da-Huang-Gan-Cao-Tang on P-Glycoprotein

    Directory of Open Access Journals (Sweden)

    Yuka Watanabe

    2012-01-01

    Full Text Available We have studied the effects of various Kampo medicines on P-glycoprotein (P-gp, a drug transporter, in vitro. The present study focused on Daiokanzoto (Da-Huang-Gan-Cao-Tang, which shows the most potent inhibitory effects on P-gp among the 50 Kampo medicines studied, and investigated the P-gp inhibitory effects of Daiokanzoto herbal ingredients (rhubarb and licorice root and their components by an ATPase assay using human P-gp membrane. Both rhubarb and licorice root significantly inhibited ATPase activity, and the effects of rhubarb were more potent than those of licorice root. The content of rhubarb in Daiokanzoto is double that in licorice root, and the inhibition patterns of Daiokanzoto and rhubarb involve both competitive and noncompetitive inhibition, suggesting that the inhibitory effects of Daiokanzoto are mainly due to rhubarb. Concerning the components of rhubarb, concentration-dependent inhibitory effects were observed for (−-catechin gallate, (−-epicatechin gallate, and (−-epigallocatechin gallate. In conclusion, rhubarb may cause changes in the drug dispositions of P-gp substrates through the inhibition of P-gp. It appears that attention should be given to the interactions between these drugs and Kampo medicines containing rhubarb as an herbal ingredient.

  18. Comparison of Methods for the Purification of Alpha-1 Acid Glycoprotein from Human Plasma

    Directory of Open Access Journals (Sweden)

    Teresa R. McCurdy

    2011-01-01

    Full Text Available Alpha-1 acid glycoprotein (AGP is a highly glycosylated, negatively charged plasma protein suggested to have anti-inflammatory and/or immunomodulatory activities. Purification of AGP could be simplified if methods that exploit its high solubility under chemically harsh conditions could be demonstrated to leave the protein in its native conformation. Procedures involving exposure of AGP to hot phenol or sulphosalicylic acid (SSA were compared to solely chromatographic methods. Hot phenol-purified AGP was more rapidly cleared from mice in vivo following intravenous injection than chromatographically purified AGP. In contrast, SSA-purified AGP demonstrated an identical in vivo clearance profile and circular dichroism spectrum to chromatographically purified AGP. Similarly, no differences in susceptibility to enzymatic deglycosylation or reactivity with Sambucus nigra lectin were detected between AGP purified via the two methods. Incorporation of the SSA step in the purification scheme for AGP eliminated the need for a large (4 mL resin/mL of plasma initial chromatographic step and simplified its purification without causing any detectable distortion in the conformation of the protein. Confirmation that this procedure is nondenaturing will simplify AGP purification and investigation of its possible biological roles in laboratory animals.

  19. Baculovirus expression of the glycoprotein gene of Lassa virus and characterization of the recombinant protein.

    Science.gov (United States)

    Hummel, K B; Martin, M L; Auperin, D D

    1992-09-01

    A recombinant baculovirus was constructed that expresses the glycoprotein gene of Lassa virus (Josiah strain) under the transcriptional control of the polyhedrin promoter. The expressed protein (B-LSGPC) comigrated with the authentic viral glycoprotein as observed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), was reactive with monoclonal antibodies (MAbs) in Western blots, and was glycosylated. Although the recombinant protein was not processed into the mature glycoproteins, G1 and G2, it demonstrated reactivity with all known epitopes as measured by indirect immunofluorescence (IFA), and it was immunogenic, eliciting antisera in rabbits that recognized whole virus in IFAs. Regarding future applications to diagnostic assays, the recombinant glycoprotein proved to be an effective substitute for Lassa virus-infected mammalian cells in IFAs and it was able to distinguish sera from several human cases of Lassa fever, against a panel of known negative sera of African origin, in an enzyme immunoassay (EIA).

  20. Generation and Characterization of an scFv Directed against Site II of Rabies Glycoprotein

    Directory of Open Access Journals (Sweden)

    Shukra M. Aavula

    2011-01-01

    Full Text Available Recombinant antibody phage display technology is a vital tool that facilitates identification of specific binding molecules to a target enabling the rapid generation and selection of high affinity, fully human, or mouse antibody product candidates essentially directed towards disease target appropriate for antibody therapy. In this study, a recombinant single-chain Fv antibody fragment (scFv A11 was isolated from immune spleen cells obtained from mice immunized with inactivated rabies virus (Pasteur strain using standard methodology and was characterized for its specificity towards the rabies virus glycoprotein. Epitope mapping using peptide libraries and truncated glycoprotein polypeptides suggested that A11 bound to the antigenic site II of rabies glycoprotein against which a majority of rabies virus neutralizing antibodies are directed. The use of the above technology could, therefore, allow development of scFvs with different specificities against the rabies glycoprotein as an alternative to the more cumbersome protocols used for the development of monoclonal antibodies.

  1. Serum sialic acid and glycoprotein levels in some Libyan cancer patients.

    Science.gov (United States)

    Balo, N N; Ishaq, M

    1991-01-01

    Sialic acid is a common conjugate of some serum glycoproteins and glycolipids. Elevated levels of serum sialic acid and alterations in serum glycoproteins have been observed in certain types of cancer. In this study sialic acid concentration in the sera of patients with various types of cancer was determined. In addition to this, serum glycoproteins were also analysed by electrophoretic method. Our results indicate that serum sialic acid levels are generally raised in all types of cancer studied. This increase was more pronounced in case of lung, bronchogenic, intestinal and breast cancer. Some alterations in the serum glycoprotein profiles were also observed, particularly in bronchogenic and gall bladder cancer where an additional band in the low molecular weight region was present and in lung, breast and lymphoma where a band in the middle molecular weight region was found missing when compared with normals.

  2. Purification of the envelope glycoproteins of western equine encephalitis virus by glass wool column chromatography.

    OpenAIRE

    Yamamoto, K.; Simizu, B

    1980-01-01

    Glass wool column chromatography was used for separation of the two glycoproteins of western equine encephalitis virus. Cross-contamination of each protein separated was confirmed to be negligible by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

  3. Evaluation of the expression of P-glycoprotein in propoxur-resistant Caco-2 cells.

    Directory of Open Access Journals (Sweden)

    Shabnam Yazdian

    2014-10-01

    Full Text Available There is a great concern about the effect of propoxur, as one of the more common N-methyl carbamate pesticides, on human health due to its extensive use in agricultural and non-agricultural applications. Caco-2 cells became resistant to propoxur, and the resistance was confirmed through MTT assay. Then the cell membrane integrity and P-glycoprotein expression were measured by LDH assay and western blot analysis, respectively and compared to the parent cells.  Contrary to what was expected, the expression of P-glycoprotein in propoxur resistant cells was lower than parent cells.This study indicates that the resistance to propoxur may not be related to P-glycoprotein expression directly, since P-glycoprotein expression has decreased in these cells.

  4. A Method for Determining the Content of Glycoproteins in Biological Samples

    Directory of Open Access Journals (Sweden)

    Yang Gao

    2016-11-01

    Full Text Available The glycoprotein purified from the mycelium extract of Tremella fuciformis was marked with iodine through the iodine substitution reaction. The content of iodine, which is indicative of the amount of the marked tremella glycoprotein (ITG, was detected with Inductively coupled plasma mass spectrometry (ICP-MS. The method was found to be stable, sensitive, and accurate at detecting the content of iodine-substituted glycoprotein, and was used in the quantitative analysis of biological samples, including blood and organs. Different biological samples were collected from rats after oral administration of ITG, and were tested for iodine content by ICP-MS to calculate the amount of ITG in the samples. The results suggested that ICP-MS is a sensitive, stable, and accurate method for detection of iodinated glycoproteins in blood and organs.

  5. Glycoproteins functionalized natural and synthetic polymers for prospective biomedical applications: A review.

    Science.gov (United States)

    Tabasum, Shazia; Noreen, Aqdas; Kanwal, Arooj; Zuber, Mohammad; Anjum, Muhammad Naveed; Zia, Khalid Mahmood

    2017-05-01

    Glycoproteins have multidimensional properties such as biodegradability, biocompatibility, non-toxicity, antimicrobial and adsorption properties; therefore, they have wide range of applications. They are blended with different polymers such as chitosan, carboxymethyl cellulose (CMC), polyvinyl pyrrolidone (PVP), polycaprolactone (PCL), heparin, polystyrene fluorescent nanoparticles (PS-NPs) and carboxyl pullulan (PC) to improve their properties like thermal stability, mechanical properties, resistance to pH, chemical stability and toughness. Considering the versatile charateristics of glycoprotein based polymers, this review sheds light on synthesis and characterization of blends and composites of glycoproteins, with natural and synthetic polymers and their potential applications in biomedical field such as drug delivery system, insulin delivery, antimicrobial wound dressing uses, targeting of cancer cells, development of anticancer vaccines, development of new biopolymers, glycoproteome research, food product and detection of dengue glycoproteins. All the technical scientific issues have been addressed; highlighting the recent advancement. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Antibody to the E3 Glycoprotein Protects Mice against Lethal Venezuelan Equine Encephalitis Virus Infection▿

    Science.gov (United States)

    Parker, Michael D.; Buckley, Marilyn J.; Melanson, Vanessa R.; Glass, Pamela J.; Norwood, David; Hart, Mary Kate

    2010-01-01

    Six monoclonal antibodies were isolated that exhibited specificity for a furin cleavage site deletion mutant (V3526) of Venezuelan equine encephalitis virus (VEEV). These antibodies comprise a single competition group and bound the E3 glycoprotein of VEEV subtype I viruses but failed to bind the E3 glycoprotein of other alphaviruses. These antibodies neutralized V3526 virus infectivity but did not neutralize the parental strain of Trinidad donkey (TrD) VEEV. However, the E3-specific antibodies did inhibit the production of virus from VEEV TrD-infected cells. In addition, passive immunization of mice demonstrated that antibody to the E3 glycoprotein provided protection against lethal VEEV TrD challenge. This is the first recognition of a protective epitope in the E3 glycoprotein. Furthermore, these results indicate that E3 plays a critical role late in the morphogenesis of progeny virus after E3 appears on the surfaces of infected cells. PMID:20926570

  7. Boronic Acid-Based Approach for Separation and Immobilization of Glycoproteins and Its Application in Sensing

    Science.gov (United States)

    Wang, Xiaojin; Xia, Ning; Liu, Lin

    2013-01-01

    Glycoproteins influence a broad spectrum of biological processes including cell-cell interaction, host-pathogen interaction, or protection of proteins against proteolytic degradation. The analysis of their glyco-structures and concentration levels are increasingly important in diagnosis and proteomics. Boronic acids can covalently react with cis-diols in the oligosaccharide chains of glycoproteins to form five- or six-membered cyclic esters. Based on this interaction, boronic acid-based ligands and materials have attracted much attention in both chemistry and biology as the recognition motif for enrichment and chemo/biosensing of glycoproteins in recent years. In this work, we reviewed the progress in the separation, immobilization and detection of glycoproteins with boronic acid-functionalized materials and addressed its application in sensing. PMID:24141187

  8. Boronic Acid-Based Approach for Separation and Immobilization of Glycoproteins and Its Application in Sensing

    Directory of Open Access Journals (Sweden)

    Lin Liu

    2013-10-01

    Full Text Available Glycoproteins influence a broad spectrum of biological processes including cell-cell interaction, host-pathogen interaction, or protection of proteins against proteolytic degradation. The analysis of their glyco-structures and concentration levels are increasingly important in diagnosis and proteomics. Boronic acids can covalently react with cis-diols in the oligosaccharide chains of glycoproteins to form five- or six-membered cyclic esters. Based on this interaction, boronic acid-based ligands and materials have attracted much attention in both chemistry and biology as the recognition motif for enrichment and chemo/biosensing of glycoproteins in recent years. In this work, we reviewed the progress in the separation, immobilization and detection of glycoproteins with boronic acid-functionalized materials and addressed its application in sensing.

  9. Distribution of surface glycoproteins on influenza A virus determined by electron cryotomography.

    Science.gov (United States)

    Wasilewski, Sebastian; Calder, Lesley J; Grant, Tim; Rosenthal, Peter B

    2012-12-07

    We use electron cryotomography to reconstruct virions of two influenza A H3N2 virus strains. The maps reveal the structure of the viral envelope containing hemagglutinin (HA) and neuraminidase (NA) glycoproteins and the virus interior containing a matrix layer and an assembly of ribonucleoprotein particles (RNPs) that package the genome. We build a structural model for the viral surface by locating copies of the X-ray structure of the HA ectodomain into density peaks on the virus surface. We calculate inter-glycoprotein distances and the fractional volume occupied by glycoproteins. The models suggest that for typical HA densities on virus, Fabs can bind to epitopes on the HA stem domain. The models also show how membrane curvature may influence the number of glycoproteins that can simultaneously interact with a target surface of receptors.

  10. Machupo Virus Glycoprotein Determinants for Human Transferrin Receptor 1 Binding and Cell Entry

    Science.gov (United States)

    2011-07-01

    and form enveloped virions [1]. Seven arenaviruses cause viral hemorrhagic fever in humans: the Old World arenaviruses Lassa and ‘Lujo,’ and the New...hemorrhagic fever in humans. MACV, as well as other pathogenic New World arenaviruses, enter cells after their GP1 attachment glycoprotein binds to... fever in humans. MACV, as well as other pathogenic New World arenaviruses, enter cells after their GP1 attachment glycoprotein binds to their cellular

  11. The quality control of glycoprotein folding in the endoplasmic reticulum, a trip from trypanosomes to mammals

    Directory of Open Access Journals (Sweden)

    A.J. Parodi

    1998-05-01

    Full Text Available The present review deals with the stages of synthesis and processing of asparagine-linked oligosaccharides occurring in the lumen of the endoplasmic reticulum and their relationship to the acquisition by glycoproteins of their proper tertiary structures. Special emphasis is placed on reactions taking place in trypanosomatid protozoa since their study has allowed the detection of the transient glucosylation of glycoproteins catalyzed by UDP-Glc:glycoprotein glucosyltransferase and glucosidase II. The former enzyme has the unique property of covalently tagging improperly folded conformations by catalyzing the formation of protein-linked Glc1Man7GlcNAc2, Glc1Man8GlcNac2 and Glc1Man9GlcNAc2 from the unglucosylated proteins. Glucosyltransferase is a soluble protein of the endoplasmic reticulum that recognizes protein domains exposed in denatured but not in native conformations (probably hydrophobic amino acids and the innermost N-acetylglucosamine unit that is hidden from macromolecular probes in most native glycoproteins. In vivo, the glucose units are removed by glucosidase II. The influence of oligosaccharides in glycoprotein folding is reviewed as well as the participation of endoplasmic reticulum chaperones (calnexin and calreticulin that recognize monoglucosylated species in the same process. A model for the quality control of glycoprotein folding in the endoplasmic reticulum, i.e., the mechanism by which cells recognize the tertiary structure of glycoproteins and only allow transit to the Golgi apparatus of properly folded species, is discussed. The main elements of this control are calnexin and calreticulin as retaining components, the UDP-Glc:glycoprotein glucosyltransferase as a sensor of tertiary structures and glucosidase II as the releasing agent.

  12. Spatial distribution of Reissner's fiber glycoproteins in the filum terminale of the rat and rabbit.

    Science.gov (United States)

    Molina, B; Rodríguez, E M; Peruzzo, B; Caprile, T; Nualart, F

    2001-03-01

    The subcommissural organ secretes into the third ventricle glycoproteins that condense to form the Reissner's fiber (RF). At the distal end of the central canal of the spinal cord, the RF-glycoproteins accumulate in the form of an irregular mass known as massa caudalis. Antibodies against RF-glycoproteins and a set of lectins were used at the light and electron microscopic level to investigate the spatial distribution of the massa caudalis material in the rat and rabbit filum terminale. In the sacral region of the rat, the central canal presents gaps between the ependymal cells through which RF-glycoproteins spread out. The bulk of massa caudalis material, however, escapes through openings in the dorsal wall of the terminal ventricle. In the rabbit, the massa caudalis is formed within the ependymal canal, at the level of the second coccygeal vertebra, it accumulates within preterminal and terminal dilatations of the central canal, and it escapes out through gaps in the dorsal ependymal wall of the terminal ventricle. The existence of wide intercellular spaces and a large orifice (neuroporous) in the dorsal ependymal wall of the terminal ventricle, and the passage of RF-material through them, appear to be conserved evolutionary features. After leaving the terminal ventricle of the rat and rabbit, RF-glycoproteins establish a close spatial association with the numerous blood vessels irrigating the filum terminale, suggesting that in these species the blood vessels are the site of destination of the RF-glycoproteins escaping from the central canal, thus resembling the situation found in lower vertebrates. When passing from the RF stage to the massa caudalis stage, the rabbit RF-glycoproteins lose their sialic acid residues, exposing galactose as the terminal residue. Since this sialic acid-galactose modification of RF-glycoproteins had also been described in lamprey larvae, it may be regarded as a conserved evolutionary feature associated with the formation of the

  13. Sonochemical synthesis of novel pyrano[3,4-e][1,3]oxazines: A green protocol.

    Science.gov (United States)

    Saleh, Tamer S; Al-Bogami, Abdullah S; Mekky, Ahmed E M; Alkhathlan, Hamad Z

    2017-05-01

    The atom-efficient and green protocol for formation of pyrano[3,4-e][1,3]oxazines utilizing dimethyl carbonate under ultrasound irradiation in a presence of KF/basic alumina was reported. We provide a novel series of pyrano[3,4-e][1,3]oxazine derivatives interesting for biological screening tests. In general, it was found that ultrasound irradiations enable the reactions to occur which could not be carried out under silent conditions. These remarkable effects appeared in sonicated reactions can be reasonably interpreted in terms of acoustic cavitation phenomenon. Structures of the products were established on analytical and spectral data. This protocol offers several advantages attain many principles of green chemistry including, save energy, atom economy, clean reactions, inexpensive green reagent and use catalysts rather than stoichiometric reagents.

  14. Introduction to the Payloads and the Initial Observation Results of Chang'E-1

    Institute of Scientific and Technical Information of China (English)

    SUN Huixian; CHEN Xiaomin; OUYANG Ziyuan; ZOU Yongliao; WU Ji; DAI Shuwu; ZHAO Baochang; SHU Rong; CHANG Jin; WANG Huanyu; ZHANG Xiaohui; REN Qiongying

    2008-01-01

    Chang'E-1, the orbiter circling the moon 200km above the moon surface, is the first Chinese Lunar exploration satellite. The satellite was successfully launched on 24th October 2007.There are 8 kinds of scientific payloads onboard, including the stereo camera, the laser altimeter, the Sagnac-based interferometer image spectrometer, the Gamma ray spectrometer, the X-ray spectrometer, the microwave radiometer, the high energy particle detector, the solar wind plasma detector and a supporting payload data management system. Chang'E-1 opened her eyes to look at the moon and took the first batch of lunar pictures after her stereo camera was switched on in 20th November 2007.Henceforth all the instruments are successfully switched on one by one. After a period of parameter adjustment and initial check out, all scientific instruments are now in their normal operating phase.In this paper, the payloads and the initial observation results are introduced.

  15. Analysis of COPII Vesicles Indicates a Role for the Emp47-Ssp120 Complex in Transport of Cell Surface Glycoproteins.

    Science.gov (United States)

    Margulis, Neil G; Wilson, Joshua D; Bentivoglio, Christine M; Dhungel, Nripesh; Gitler, Aaron D; Barlowe, Charles

    2016-03-01

    Coat protein complex II (COPII) vesicle formation at the endoplasmic reticulum (ER) transports nascent secretory proteins forward to the Golgi complex. To further define the machinery that packages secretory cargo and targets vesicles to Golgi membranes, we performed a comprehensive proteomic analysis of purified COPII vesicles. In addition to previously known proteins, we identified new vesicle proteins including Coy1, Sly41 and Ssp120, which were efficiently packaged into COPII vesicles for trafficking between the ER and Golgi compartments. Further characterization of the putative calcium-binding Ssp120 protein revealed a tight association with Emp47 and in emp47Δ cells Ssp120 was mislocalized and secreted. Genetic analyses demonstrated that EMP47 and SSP120 display identical synthetic positive interactions with IRE1 and synthetic negative interactions with genes involved in cell wall assembly. Our findings support a model in which the Emp47-Ssp120 complex functions in transport of plasma membrane glycoproteins through the early secretory pathway.

  16. Cysteine-rich secretory protein 3 is a ligand of alpha1B-glycoprotein in human plasma

    DEFF Research Database (Denmark)

    Udby, Lene; Sørensen, Ole E; Pass, Jesper

    2004-01-01

    Human cysteine-rich secretory protein 3 (CRISP-3; also known as SGP28) belongs to a family of closely related proteins found in mammals and reptiles. Some mammalian CRISPs are known to be involved in the process of reproduction, whereas some of the CRISPs from reptiles are neurotoxin......-like substances found in lizard saliva or snake venom. Human CRISP-3 is present in exocrine secretions and in secretory granules of neutrophilic granulocytes and is believed to play a role in innate immunity. On the basis of the relatively high content of CRISP-3 in human plasma and the small size of the protein...... (28 kDa), we hypothesized that CRISP-3 in plasma was bound to another component. This was supported by size-exclusion chromatography and immunoprecipitation of plasma proteins. The binding partner was identified by mass spectrometry as alpha(1)B-glycoprotein (A1BG), which is a known plasma protein...

  17. Lipid modification gives rise to two distinct Haloferax volcanii S-layer glycoprotein populations.

    Science.gov (United States)

    Kandiba, Lina; Guan, Ziqiang; Eichler, Jerry

    2013-03-01

    The S-layer glycoprotein is the sole component of the protein shell surrounding Haloferax volcanii cells. The deduced amino acid sequence of the S-layer glycoprotein predicts the presence of a C-terminal membrane-spanning domain. However, several earlier observations, including the ability of EDTA to selectively solubilize the protein, are inconsistent with the presence of a trans-membrane sequence. In the present report, sequential solubilization of the S-layer glycoprotein by EDTA and then with detergent revealed the existence of two distinct populations of the S-layer glycoprotein. Whereas both S-layer glycoprotein populations underwent signal peptide cleavage and N-glycosylation, base hydrolysis followed by mass spectrometry revealed that a lipid, likely archaetidic acid, modified only the EDTA-solubilized version of the protein. These observations are consistent with the S-layer glycoprotein being initially synthesized as an integral membrane protein and subsequently undergoing a processing event in which the extracellular portion of the protein is separated from the membrane-spanning domain and transferred to a waiting lipid moiety.

  18. The importance of drug-transporting P-glycoproteins in toxicology.

    Science.gov (United States)

    van Tellingen, O

    2001-03-31

    The importance of specific transport in toxicology is becoming increasingly clear and the work on P-glycoprotein has certainly been a major contribution to these growing insights. P-Glycoproteins were discovered by their ability to confer multidrug resistance in mammalian tumour cells. They are localised in the cell membrane where they actively extrude a wide range of compounds including many anti-cancer drugs from the cell. Besides in tumour cells, drug-transporting P-glycoproteins are also expressed in a polarised fashion in normal tissues that perform an excretory or barrier function, such as the liver, kidneys, intestines, brain endothelial cells. Based on this expression profile, it has been proposed that P-glycoproteins are important in protecting the host by reducing exposure to xenobiotics. Further studies with P-glycoprotein knockout mice have clearly established this protective function. In general, the clearance of substrate drugs is lower in knockout mice due to a diminished hepatobiliary excretion, direct intestinal excretion and/or increased enterohepatic cycling. Moreover, their uptake in sanctuary sites, such as the brain or the foetus, was profoundly higher in P-glycoprotein knockout mice, as was the uptake of drugs from the gastro-intestinal tract into the systemic circulation following oral ingestion. These results clearly highlight the impact that transport proteins can play in toxicology.

  19. Bile canalicular cationic dye secretion as a model for P-glycoprotein mediated transport.

    Science.gov (United States)

    Thalhammer, T; Stapf, V; Gajdzik, L; Graf, J

    1994-04-01

    This study explores properties of P-glycoprotein dependent membrane transport in rat liver with the use of acridine orange as the substrate. We studied the biliary secretion of the dye, its binding to canalicular membrane P-glycoprotein, and effects of the inhibitor cyclosporin A: acridine orange is excreted into bile together with less hydrophobic and glucuronidated metabolites. Cyclosporin A inhibited both the secretion of acridine orange and of its metabolites. In TR- animals, a rat strain that is deficient of the canalicular multi-specific organic anion transport system, non-metabolized acridine orange is the predominant species in bile and its secretion is also inhibited by cyclosporin A. Binding of acridine orange to liver P-glycoprotein was analyzed by photoaffinity labeling with azidopine, a substrate of P-glycoprotein dependent transport in multi-drug resistant tumor cells. Labeling of the immunoprecipitated P-glycoprotein was inhibited by acridine orange, verapamil, and by cyclosporin A. The results show that biliary secretion of acridine orange is highly analogous to P-glycoprotein mediated membrane drug transport in tumor cells that exhibit multi-drug resistance.

  20. Molecular docking studies with rabies virus glycoprotein to design viral therapeutics

    Directory of Open Access Journals (Sweden)

    Tomar N

    2010-01-01

    Full Text Available The genome of rabies virus encodes five proteins; the nucleoprotein, the phosphoprotein, the matrix protein, the glycoprotein, and the RNA-dependent RNA polymerase. Among these, the glycoprotein is the most important as it is the major contributor to pathogenicity and virus neutralizing antibody response. Keeping in mind that glycoprotein is the only protein exposed on the surface of virus and is thought to be responsible for the interaction with the cell membrane, it was attempted to target glycoprotein by a ligand polyethylene glycol 4000, which blocks its active site, as seen by molecular operating environment software, so that it may be possible to prevent the spread of virus into the host. The ligand polyethylene glycol 4000 was retrieved from Research Collaboratory for Structural Bioinformatics protein data bank by providing the glycoprotein sequence to the databank. In this study it was observed that the ligand was successfully docked on a major portion of antigenic site II of glycoprotein by mimicking the virus neutralizing antibodies. This knowledge may be important for the development of novel therapies for the treatment of rabies and other viral diseases in the future.

  1. Surface plasmon resonance for real-time study of lectin-carbohydrate interactions for the differentiation and identification of glycoproteins.

    Science.gov (United States)

    Safina, Gulnara; Duran, Iu Benet; Alasel, Mohammed; Danielsson, Bengt

    2011-06-15

    A study of specific interactions between lectins and glycoproteins has been carried out using surface plasmon resonance (SPR) in a flow-injection mode. Lectins were covalently immobilised on the surfaces of the microfluidic sensor chip via amine coupling and serum glycoproteins were injected into the flow channels. Specific lectin-glycoprotein interactions caused the shift of refractive index proportional to the mass concentration accumulated on the channel surface. Lectins showed different affinity to the tested glycoproteins and each glycoprotein displayed its own lectin-binding pattern. It is possible to distinguish and identify even glycoproteins with similar sugar structures by simple and quick screening. The working conditions of the assay were optimised. The lectin-based SPR made it possible to carry out the label-free detection of glycoproteins within a broad concentration range with a good linearity. Regeneration conditions for the surface of the sensor chip were found and optimised. Combination of 10mM HCl and 10mM glycine-HCl (pH 2.5) removes the bound glycoproteins from the lectin surface without damaging it. The kinetic and affinity parameters of lectin-glycoprotein binding were evaluated. The proposed method was tested on human glycosylated serum. Combination of the lectin panel with SPR is suitable both for specific screening and for sensitive assay of serum glycoproteins.

  2. Adiponectin and AMP kinase activator stimulate proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells

    Directory of Open Access Journals (Sweden)

    Yamauchi Mika

    2007-11-01

    Full Text Available Abstract Background Adiponectin is a key mediator of the metabolic syndrome that is caused by visceral fat accumulation. Adiponectin and its receptors are known to be expressed in osteoblasts, but their actions with regard to bone metabolism are still unclear. In this study, we investigated the effects of adiponectin on the proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells. Results Adiponectin receptor type 1 (AdipoR1 mRNA was detected in the cells by RT-PCR. The adenosine monophosphate-activated protein kinase (AMP kinase was phosphorylated by both adiponectin and a pharmacological AMP kinase activator, 5-amino-imidazole-4-carboxamide-riboside (AICAR, in the cells. AdipoR1 small interfering RNA (siRNA transfection potently knocked down the receptor mRNA, and the effect of this knockdown persisted for as long as 10 days after the transfection. The transfected cells showed decreased expressions of type I collagen and osteocalcin mRNA, as determined by real-time PCR, and reduced ALP activity and mineralization, as determined by von Kossa and Alizarin red stainings. In contrast, AMP kinase activation by AICAR (0.01–0.5 mM in wild-type MC3T3-E1 cells augmented their proliferation, differentiation, and mineralization. BrdU assay showed that the addition of adiponectin (0.01–1.0 μg/ml also promoted their proliferation. Osterix, but not Runx-2, appeared to be involved in these processes because AdipoR1 siRNA transfection and AICAR treatments suppressed and enhanced osterix mRNA expression, respectively. Conclusion Taken together, this study suggests that adiponectin stimulates the proliferation, differentiation, and mineralization of osteoblasts via the AdipoR1 and AMP kinase signaling pathways in autocrine and/or paracrine fashions.

  3. DMSO is a strong inducer of DNA hydroxymethylation in pre-osteoblastic MC3T3-E1 cells

    Science.gov (United States)

    Thaler, Roman; Spitzer, Silvia; Karlic, Heidrun; Klaushofer, Klaus; Varga, Franz

    2012-01-01

    Artificial induction of active DNA demethylation appears to be a possible and useful strategy in molecular biology research and therapy development. Dimethyl sulfoxide (DMSO) was shown to cause phenotypic changes in embryonic stem cells altering the genome-wide DNA methylation profiles. Here we report that DMSO increases global and gene-specific DNA hydroxymethylation levels in pre-osteoblastic MC3T3-E1 cells. After 1 day, DMSO increased the expression of genes involved in DNA hydroxymethylation (TET) and nucleotide excision repair (GADD45) and decreased the expression of genes related to DNA methylation (Dnmt1, Dnmt3b, Hells). Already 12 hours after seeding, before first replication, DMSO increased the expression of the pro-apoptotic gene Fas and of the early osteoblastic factor Dlx5, which proved to be Tet1 dependent. At this time an increase of 5-methyl-cytosine hydroxylation (5-hmC) with a concomitant loss of methyl-cytosines on Fas and Dlx5 promoters as well as an increase in global 5-hmC and loss in global DNA methylation was observed. Time course-staining of nuclei suggested euchromatic localization of DMSO induced 5-hmC. As consequence of induced Fas expression, caspase 3/7 and 8 activities were increased indicating apoptosis. After 5 days, the effect of DMSO on promoter- and global methylation as well as on gene expression of Fas and Dlx5 and on caspases activities was reduced or reversed indicating down-regulation of apoptosis. At this time, up regulation of genes important for matrix synthesis suggests that DMSO via hydroxymethylation of the Fas promoter initially stimulates apoptosis in a subpopulation of the heterogeneous MC3T3-E1 cell line, leaving a cell population of extra-cellular matrix producing osteoblasts.  PMID:22507896

  4. Common Structure of Rare Replication-Deficient E1-Positive Particles in Adenoviral Vector Batches

    Science.gov (United States)

    Murakami, Pete; Havenga, Menzo; Fawaz, Farah; Vogels, Ronald; Marzio, Giuseppe; Pungor, Erno; Files, Jim; Do, Linh; Goudsmit, Jaap; McCaman, Michael

    2004-01-01

    The use of the PER.C6 adenovirus packaging cell line in combination with a designated vector plasmid system, whereby the cell line and vector with E1 deleted have no sequence overlap, eliminates the generation of replication-competent adenovirus during vector production. However, we have found cytopathic effect (CPE)-inducing particles in 2 out of more than 40 large-scale manufacturing lots produced in PER.C6 cells. The CPE inducer was detected at a frequency of 1 event in 7.5 × 1012 vector particles. Despite amplification, it was not readily purified, indicating that the agent itself is replication deficient and requires the parental recombinant adenovirus serotype 5 (rAd5) vector for replication and packaging. Therefore, we designated the agent as a helper-dependent E1-positive region containing viral particle (HDEP). Here, we report the molecular structure of the HDEP genome, revealing an Ad comprised of E1 sequences derived from PER.C6 cells flanked by inverted terminal repeat, packaging signal, and transgene sequences. These sequences form a palindromic structure devoid of E2, E3, E4, and late genes. Since only 5 bp were shared between E1 sequences in the PER.C6 genome and viral vector sequences, the data strongly suggested that insertion of genomic DNA into an adenoviral genome had occurred essentially via nonhomologous recombination. HDEPs have been found in unrelated virus batches and appear to share a common structure that may explain their mechanism of generation. This finding allowed development of an HDEP assay to screen batches of rAd5 produced on the PER.C6 cell line and resulted in detection of seven HDEP agents from four different transgene-virus vector constructs in separate batches of Ad. PMID:15163713

  5. Mouse Spermatocytes Express CYP2E1 and Respond to Acrylamide Exposure

    Science.gov (United States)

    Nixon, Belinda J.; Katen, Aimee L.; Stanger, Simone J.; Schjenken, John E.; Nixon, Brett; Roman, Shaun D.

    2014-01-01

    Metabolism of xenobiotics by cytochrome P450s (encoded by the CYP genes) often leads to bio-activation, producing reactive metabolites that interfere with cellular processes and cause DNA damage. In the testes, DNA damage induced by xenobiotics has been associated with impaired spermatogenesis and adverse effects on reproductive health. We previously reported that chronic exposure to the reproductive toxicant, acrylamide, produced high levels of DNA damage in spermatocytes of Swiss mice. CYP2E1 metabolises acrylamide to glycidamide, which, unlike acrylamide, readily forms adducts with DNA. Thus, to investigate the mechanisms of acrylamide toxicity in mouse male germ cells, we examined the expression of the CYP, CYP2E1, which metabolises acrylamide. Using Q-PCR and immunohistochemistry, we establish that CYP2E1 is expressed in germ cells, in particular in spermatocytes. Additionally, CYP2E1 gene expression was upregulated in these cells following in vitro acrylamide exposure (1 µM, 18 h). Spermatocytes were isolated and treated with 1 µM acrylamide or 0.5 µM glycidamide for 18 hours and the presence of DNA-adducts was investigated using the comet assay, modified to detect DNA-adducts. Both compounds produced significant levels of DNA damage in spermatocytes, with a greater response observed following glycidamide exposure. A modified comet assay indicated that direct adduction of DNA by glycidamide was a major source of DNA damage. Oxidative stress played a small role in eliciting this damage, as a relatively modest effect was found in a comet assay modified to detect oxidative adducts following glycidamide exposure, and glutathione levels remained unchanged following treatment with either compound. Our results indicate that the male germ line has the capacity to respond to xenobiotic exposure by inducing detoxifying enzymes, and the DNA damage elicited by acrylamide in male germ cells is likely due to the formation of glycidamide adducts. PMID:24788432

  6. Repression of insulin gene expression by adenovirus type 5 E1a proteins.

    OpenAIRE

    1987-01-01

    Insulin gene transcription relies on enhancer and promoter elements which are active in pancreatic beta cells. We showed that adenovirus type 5 infection of HIT T-15 cells, a transformed hamster beta cell line, represses insulin gene transcription and mRNA levels. Using expression plasmids transiently introduced into HIT T-15 cells, we showed that adenovirus type 5 E1a transcription regulatory proteins repress insulin enhancer-promoter element activity as assayed with a surrogate xanthine-gua...

  7. Ultrasound associated uptake of chitosan nanoparticles in MC3T3-E1 cells

    Science.gov (United States)

    Wu, Junyi

    Chitosan is a natural linear polysaccharide that has been well known for its applications in drug delivery system due to its unique physicochemical and biological properties. However, challenges still remain for it to become a fully realized therapeutic agent. In this study, we investigated the uptake of chitosan nanoparticles (CNP) under the ultrasound stimulation, using a model cell culture system (MC3T3-E1 mouse pre-osteoblasts). The CNP were fabricated by an ionic gelation method and were lyophilized prior to characterization and delivery to cells. Particle size and zeta potential were measured using Dynamic Light Scattering (DLS); the efficiency of chitosan complexation was measured using the ninhydrin assay. Cytotoxicity was examined by neutral red assay within 48 hours after delivery. The effect of ultrasound (US) on the efficiency of nanoparticle delivery to the MC3T3-E1 cells was examined at 1MHz and at either 1 or 2 W/cm2. Fluorescein isothiocyanate (FITC)-conjugated-CNP were used to visualize the internalized particles within the cytosol. The uptake of FITC-CNP exhibits a dose and time dependent effect, a strong FITC fluorescence was detected at the concentration of 500microg/mL under fluorescence microscope. Ultrasound assisted uptake of FITC-CNP performed a significant positive effect at 2W/cm2 with 60s of ultrasound exposure time. CNP displayed a slightly decrease in cell viability from 25microg/mL to 100microg/mL, while higher concentration of CNP facilitates the proliferation of MC3T3-E1 cells. Less than 10% of reduction in cell viability was observed for US at 1W/cm2 and 2W/cm2 with 30s and 60s of exposure time, which suggest a mild effect of US to MC3T3-E1 cell line.

  8. Calculation of Radiative Corrections to E1 matrix elements in the Neutral Alkalis

    Energy Technology Data Exchange (ETDEWEB)

    Sapirstein, J; Cheng, K T

    2004-09-28

    Radiative corrections to E1 matrix elements for ns-np transitions in the alkali metal atoms lithium through francium are evaluated. They are found to be small for the lighter alkalis but significantly larger for the heavier alkalis, and in the case of cesium much larger than the experimental accuracy. The relation of the matrix element calculation to a recent decay rate calculation for hydrogenic ions is discussed, and application of the method to parity nonconservation in cesium is described.

  9. E1DS: catalytic site prediction based on 1D signatures of concurrent conservation

    OpenAIRE

    2008-01-01

    Large-scale automatic annotation of protein sequences remains challenging in postgenomics era. E1DS is designed for annotating enzyme sequences based on a repository of 1D signatures. The employed sequence signatures are derived using a novel pattern mining approach that discovers long motifs consisted of several sequential blocks (conserved segments). Each of the sequential blocks is considerably conserved among the protein members of an EC group. Moreover, a signature includes at least thre...

  10. Definition of a major p53 binding site on Ad2E1B58K protein and a possible nuclear localization signal on the Ad12E1B54K protein.

    Science.gov (United States)

    Grand, R J; Parkhill, J; Szestak, T; Rookes, S M; Roberts, S; Gallimore, P H

    1999-01-28

    Previous studies have established that adenovirus 2/5 early region 1B (Ad E1B) 58K protein binds p53 strongly and co-localizes with it to cytoplasmic dense bodies whilst the homologous Ad12E1B54K protein binds only weakly and co-localizes primarily to the nucleus in Ad12E1 transformed cells. We have used these properties of the E1B proteins from different viral serotypes to map the p53 binding site on the Ad2/5 protein. A set of chimaeric genes was constructed containing different proportions of the Ad12 and Ad2E1B DNA. These, together with Ad12E1A and E1B19K DNA, were transfected into baby rat kidney cells and transformed lines isolated. From an examination of the properties of these Ad12/Ad2E1B fusion proteins in co-immunoprecipitation and subcellular localization experiments it has been concluded that the p53 binding site on Ad2E1B58K protein lies between amino acids 216 and 235 and that the homologous region on Ad12E1B54K protein also binds p53. In addition, a unique nuclear localization signal is located on Ad12E1B54K between residues 228 and 239. We suggest that primary structure differences in these regions of the Ad2 and Ad12E1B proteins are responsible for the different subcellular localizations in AdE1 transformants.

  11. CYP1A1 and CYP2E1 polymorphism frequencies in a large Brazilian population

    Directory of Open Access Journals (Sweden)

    Renata dos Santos Coura

    2007-01-01

    Full Text Available The enzymes encoded by the polymorphic genes CYP1A1 and CYP2E1 play an important role in the activation and inactivation of xenobiotics. These enzymes have been associated with xenobiotic-induced diseases, such as cancer, therapeutic failure and adverse effects of drugs. The aim of the present study was to determine the allelic and genotypic frequencies of these polymorphisms in a large, ethnically mixed Brazilian population sample from Rio de Janeiro. Polymorphisms CYP1A1 and CYP2E1 were determined in 870 unrelated individuals by PCR-RFLP analysis in peripheral blood DNA. The observed allelic frequencies were 0.90 for CYP1A1*1A and 0.95 for CYP2E1*1A, in the total sample. The allelic frequency of CYP1A1*2C in "pardos" (0.13 and Brazilian whites (0.11 was higher than in Caucasians (0.05, which may be a result of the Amerindian genetic component, that presents the highest frequency of this allele observed up to now. The genotype distributions for both polymorphisms were in Hardy-Weinberg equilibrium and were statistically different between males and females, and among ethnic groups.

  12. Construction and in vitro Study of an E1B-Defective Adenovirus

    Institute of Scientific and Technical Information of China (English)

    Xue Feng; Joshua Mallam Nock; Zhu Hua-bin; Dong Chang-yuan; Qi Yi-peng

    2004-01-01

    An E1B-defective adenovirus named r1/Ad was constructed by homologous recombination. The construction, selection and propagation of recombinant virus was done in the human embryonic kidney 293 cells (HEK293). The in vitro study demonstrated that the recombinant virus has the ability to replicate in and lyse some p53-deficient human tumor cells such as the human glioblastoma tumor cells (U251) and human bladder tumer cells (EJ) but not in the normal cells with functional p53 such as the human fibroblast cells (MRC-5). Also, based on the cytopathic effect (CPE), it was demonstrated that the U251 cells were more sensitive to the infection of r1/Ad than that of EJ cells under identical conditions. In this paper, it was found that r1/Ad could be very useful in studying the in vitro selective replication of E1B-defective adenovirus. This may help to determine the safety of using any E1B-defective adenoviruses in cancer gene therapy.

  13. Ubiquitination independent of E1 and E2 enzymes by bacterial effectors

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Jiazhang; Sheedlo, Michael J.; Yu, Kaiwen; Tan, Yunhao; Nakayasu, Ernesto S.; Das, Chittaranjan; Liu, Xiaoyun; Luo, Zhao-Qing

    2016-04-06

    Signaling by ubiquitination regulates virtually every cellular process in eukaryotes. Covalent attachment of ubiquitin to a substrate is catalyzed by the E1, E2 and E3 three-enzyme cascade 1, which links the C terminus of ubiquitin via an isopeptide bond mostly to the ε-amino group of a lysine of the substrate. Given the essential roles of ubiquitination in the regulation of the immune system, it is not surprising that the ubiquitination network is a common target for diverse infectious agents 2. For example, many bacterial pathogens exploit ubiquitin signaling using virulence factors that function as E3 ligases, deubiquitinases 3 or as enzymes that directly attack ubiquitin 4. The bacterial pathogen Legionella pneumophila utilizes approximately 300 effectors that modulate diverse host processes to create a niche permissive for its replication in phagocytes 5. Here we demonstrate that members of the SidE effector family (SidEs) of L. pneumophila ubiquitinate multiple Rab small GTPases associated with the endoplasmic reticulum (ER). Moreover, we show that these proteins are capable of catalyzing ubiquitination without the need for the E1 and E2 enzymes. The E1/E2-independent ubiquitination catalyzed by these enzymes requires NAD but not ATP and Mg2+. A putative mono ADP-ribosyltransferase (mART) motif critical for the ubiquitination activity is also essential for the role of SidEs in intracellular bacterial replication in a protozoan host. These results establish that ubiquitination can be catalyzed by a single enzyme.

  14. The E1 protein is mandatory for pore formation by Semliki Forest virus spikes.

    Science.gov (United States)

    Dick, M; Barth, B U; Kempf, C

    1996-06-01

    Insect cells (Aedes albopictus, clone C6/36) were infected with various variants of Semliki Forest virus including the wild type using the SFV replicon system. The variants included deletion mutants lacking one of the structural proteins and a mutant with a point mutation in p62 (SQL). The latter mutation results in a failure to process p62 to E2 and E3. After infection of the cells with different variant viruses and subsequent expression of viral proteins in the host cell plasma membrane low pH-induced pore formation was detected by measuring the efflux of a radiolabeled compound. The results of these experiments clearly showed that the E1 protein is mandatory for the acid-induced pore formation. A participation of the 6K or C-protein could be excluded. Furthermore, results obtained with the SQL mutant suggest that dissociation of the E1/E2 heterodimer and subsequent homooligomerization of E1 are required for pore formation.

  15. Effects of 6-Hydroxyflavone on Osteoblast Differentiation in MC3T3-E1 Cells

    Directory of Open Access Journals (Sweden)

    Chien-Hung Lai

    2014-01-01

    Full Text Available Osteoblast differentiation plays an essential role in bone integrity. Isoflavones and some flavonoids are reported to have osteogenic activity and potentially possess the ability to treat osteoporosis. However, limited information concerning the osteogenic characteristics of hydroxyflavones is available. This study investigates the effects of various hydroxyflavones on osteoblast differentiation in MC3T3-E1 cells. The results showed that 6-hydroxyflavone (6-OH-F and 7-hydroxyflavone (7-OH-F stimulated ALP activity. However, baicalein and luteolin inhibited ALP activity and flavone showed no effect. Up to 50 μM of each compound was used for cytotoxic effects study; flavone, 6-OH-F, and 7-OH-F had no cytotoxicity on MC3T3-E1 cells. Moreover, 6-OH-F activated AKT and serine/threonine kinases (also known as protein kinase B or PKB, extracellular signal-regulated kinases (ERK 1/2, and the c-Jun N-terminal kinase (JNK signaling pathways. On the other hand, 7-OH-F promoted osteoblast differentiation mainly by activating ERK 1/ 2 signaling pathways. Finally, after 5 weeks of 6-OH-F induction, MC3T3-E1 cells showed a significant increase in the calcein staining intensity relative to merely visible mineralization observed in cells cultured in the osteogenic medium only. These results suggested that 6-OH-F could activate AKT, ERK 1/2, and JNK signaling pathways to effectively promote osteoblastic differentiation.

  16. Electric dipole strength distribution below the E1 giant resonance in N = 82 nuclei

    Science.gov (United States)

    Guliyev, Ekber; Kuliev, Ali; Guner, Mehmet

    2010-12-01

    In this study quasiparticle random-phase approximation with the translational invariant Hamiltonian using deformed mean field potential has been conducted to describe electric dipole excitations in 136Xe, 138Ba, 140Ce, 142Nd, 144Sm and 146Gd isotones. The distribution of the calculated E1 strength shows a resonance like structure at energies between 6-8 MeV exhausting up to 1% of the isovector electric dipole Energy Weighted Sum Rule and in some aspects nicely confirms the experimental data. It has been shown that the main part of E1 strength, observed below the threshold in these nuclei may be interpreted as main fragments of the Pygmy Dipole resonance. The agreement between calculated mean excitation energies as well as summed B(E1) value of the 1- excitations and the available experimental data is quite good. The calculations indicate the presence of a few prominent positive parity 1+ States in heavy N = 82 isotones in the energy interval 6-8 MeV which shows not all dipole excitations were of electric character in this energy range.

  17. Instanton induced Yukawa couplings from distant E3 and E(-1) instantons

    Energy Technology Data Exchange (ETDEWEB)

    Goodsell, Mark D. [Sorbonne Universités, UPMC Univ Paris 06, UMR 7589, LPTHE,F-75005, Paris (France); CNRS, UMR 7589, LPTHE,F-75005, Paris (France); Witkowski, Lukas T. [Institute for Theoretical Physics, University of Heidelberg,Philosophenweg 19, 69120 Heidelberg (Germany)

    2016-01-07

    We calculate non-perturbative contributions to Yukawa couplings on D3-branes at orbifold singularities due to E3 and fractional E(-1) instantons which do not intersect the visible sector branes. While distant E3 instantons on bulk cycles typically contribute to Yukawa couplings, we find that distant fractional E(-1) can also give rise to new Yukawa couplings. However, fractional E(-1) instantons only induce Yukawa couplings if they are located at a singularity which shares a collapsed homologous two-cycle with the singularity supporting the visible sector. The non-perturbative contributions to Yukawa couplings exhibit a different flavour structure than the tree-level Yukawa couplings and, as a result, they can be sources of flavour violation. This is particularly relevant for schemes of moduli stabilisation which rely on superpotential contributions from E3 instantons, such as KKLT or the Large Volume Scenario. As a byproduct of our analysis, we shed some new light on the properties of annulus diagrams with matter field insertions in stringy instanton calculus.

  18. Evidence for selective regulation of the phosphorylation of myocyte proteins by isoproterenol and prostaglandin E1.

    Science.gov (United States)

    Hayes, J S; Bowling, N; King, K L; Boder, G B

    1982-01-12

    Both isoproterenol and prostaglandin E1 increased the activation state of cyclic AMP-dependent protein kinase in cultured myocytes; however, only isoproterenol enhanced phosphorylase activity and contractile state. Following the incubation of intact myocytes with 32PO3-(4), 32 phosphoproteins were resolved from total cellular proteins by electrophoresis in sodium dodecyl sulfate polyacrylamide gels followed by autoradiography. Isoproterenol stimulated 32PO3-(4) incorporation into 16 proteins, including 2 phosphoproteins not observed under control conditions. By contrast, prostaglandin E1 neither caused a measurable change in the protein phosphorylation pattern nor interfered with isoproterenol's capacity to do so. Isoproterenol stimulated myocyte protein phosphorylation in either the presence or absence of extracellular Ca2+. The results suggest that the regulation of protein phosphorylation following adenylate cyclase stimulation is: (1) an agonist-specific process and not due solely to a random accumulation of intracellular cycle AMP and activation of protein kinase; (2) the Ca2+ mobilization component of beta-receptor activation does not account for the paradoxical effects of isoproterenol and prostaglandin E1; (3) activation of cyclic AMP-dependent protein kinase does not always result in an enhancement of protein phosphorylation.

  19. Ovarian Hormone Estrone Glucuronide (E1G) quantification-impedimetric electrochemical spectroscopy approach

    KAUST Repository

    Zia, Asif I.

    2013-12-01

    A study was conducted on detection and concentration measurement of estrone glucuronide (E1G), an important metabolite of the ovarian hormone estradiol, by using Electrochemical Impedance Spectroscopy (EIS) technique. A miniature planar Inter-digital (ID) capacitive sensor fabricated on single crystal silicon substrate with sputtered gold electrodes coupled with EIS was used to measure conductivity, permeability and dielectric properties of the said hormone metabolite. A thin film of Silicon Nitride (50 um) was coated on the sensor as passivation layer to avoid Faradic currents through the sensor. Impedance spectrums were obtained with various concentrations of E1G in buffer solution by exposing the samples to electrical perturbations at certain frequency range. Relationship of sample conductance with E1G concentration was studied on basis Randle\\'s equivalent circuit model and results were analyzed to deduce Constant Phase Equivalent (CPE) Circuit model in order to evaluate the double layer capacitance produced at the solution-electrode interface due to kinetic processes taking place in the electrochemical cell. The sensitivity of the sensor was evaluated against concentration. The result analysis confirmed that fabricated ID sensor together with EIS can provide a rapid and successful low cost sensing system which can help a lay user to determine peak time for feminine reproductive fertility at home without submitting samples for an expensive and time consuming laboratory test. © 2013 IEEE.

  20. Resolving the 3D spatial orientation of helix I in the closed state of the colicin E1 channel domain by FRET. Insights into the integration mechanism.

    Science.gov (United States)

    Lugo, Miguel R; Ho, Derek; Merrill, A Rod

    2016-10-15

    Current evidence suggests that the c