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Sample records for human activated protein

  1. Protein S binding to human endothelial cells is required for expression of cofactor activity for activated protein C

    NARCIS (Netherlands)

    Hackeng, T. M.; Hessing, M.; van 't Veer, C.; Meijer-Huizinga, F.; Meijers, J. C.; de Groot, P. G.; van Mourik, J. A.; Bouma, B. N.

    1993-01-01

    An important feedback mechanism in blood coagulation is supplied by the protein C/protein S anticoagulant pathway. In this study we demonstrate that the binding of human protein S to cultured human umbilical vein endothelial cells (HUVECs) is required for the expression of cofactor activity of

  2. Modeling of human factor Va inactivation by activated protein C

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    Bravo Maria

    2012-05-01

    Full Text Available Abstract Background Because understanding of the inventory, connectivity and dynamics of the components characterizing the process of coagulation is relatively mature, it has become an attractive target for physiochemical modeling. Such models can potentially improve the design of therapeutics. The prothrombinase complex (composed of the protease factor (FXa and its cofactor FVa plays a central role in this network as the main producer of thrombin, which catalyses both the activation of platelets and the conversion of fibrinogen to fibrin, the main substances of a clot. A key negative feedback loop that prevents clot propagation beyond the site of injury is the thrombin-dependent generation of activated protein C (APC, an enzyme that inactivates FVa, thus neutralizing the prothrombinase complex. APC inactivation of FVa is complex, involving the production of partially active intermediates and “protection” of FVa from APC by both FXa and prothrombin. An empirically validated mathematical model of this process would be useful in advancing the predictive capacity of comprehensive models of coagulation. Results A model of human APC inactivation of prothrombinase was constructed in a stepwise fashion by analyzing time courses of FVa inactivation in empirical reaction systems with increasing number of interacting components and generating corresponding model constructs of each reaction system. Reaction mechanisms, rate constants and equilibrium constants informing these model constructs were initially derived from various research groups reporting on APC inactivation of FVa in isolation, or in the presence of FXa or prothrombin. Model predictions were assessed against empirical data measuring the appearance and disappearance of multiple FVa degradation intermediates as well as prothrombinase activity changes, with plasma proteins derived from multiple preparations. Our work integrates previously published findings and through the cooperative

  3. Chaperone activity of human small heat shock protein-GST fusion proteins.

    Science.gov (United States)

    Arbach, Hannah; Butler, Caley; McMenimen, Kathryn A

    2017-07-01

    Small heat shock proteins (sHsps) are a ubiquitous part of the machinery that maintains cellular protein homeostasis by acting as molecular chaperones. sHsps bind to and prevent the aggregation of partially folded substrate proteins in an ATP-independent manner. sHsps are dynamic, forming an ensemble of structures from dimers to large oligomers through concentration-dependent equilibrium dissociation. Based on structural studies and mutagenesis experiments, it is proposed that the dimer is the smallest active chaperone unit, while larger oligomers may act as storage depots for sHsps or play additional roles in chaperone function. The complexity and dynamic nature of their structural organization has made elucidation of their chaperone function challenging. HspB1 and HspB5 are two canonical human sHsps that vary in sequence and are expressed in a wide variety of tissues. In order to determine the role of the dimer in chaperone activity, glutathione-S-transferase (GST) was genetically linked as a fusion protein to the N-terminus regions of both HspB1 and HspB5 (also known as Hsp27 and αB-crystallin, respectively) proteins in order to constrain oligomer formation of HspB1 and HspB5, by using GST, since it readily forms a dimeric structure. We monitored the chaperone activity of these fusion proteins, which suggest they primarily form dimers and monomers and function as active molecular chaperones. Furthermore, the two different fusion proteins exhibit different chaperone activity for two model substrate proteins, citrate synthase (CS) and malate dehydrogenase (MDH). GST-HspB1 prevents more aggregation of MDH compared to GST-HspB5 and wild type HspB1. However, when CS is the substrate, both GST-HspB1 and GST-HspB5 are equally effective chaperones. Furthermore, wild type proteins do not display equal activity toward the substrates, suggesting that each sHsp exhibits different substrate specificity. Thus, substrate specificity, as described here for full-length GST

  4. Outer Membrane Protein 25 of Brucella Activates Mitogen-Activated Protein Kinase Signal Pathway in Human Trophoblast Cells

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    Jing Zhang

    2017-12-01

    Full Text Available Outer membrane protein 25 (OMP25, a virulence factor from Brucella, plays an important role in maintaining the structural stability of Brucella. Mitogen-activated protein kinase (MAPK signal pathway widely exists in eukaryotic cells. In this study, human trophoblast cell line HPT-8 and BALB/c mice were infected with Brucella abortus 2308 strain (S2308 and 2308ΔOmp25 mutant strain. The expression of cytokines and activation of MAPK signal pathway were detected. We found that the expressions of tumor necrosis factor-α, interleukin-1, and interleukin-10 (IL-10 were increased in HPT-8 cells infected with S2308 and 2308ΔOmp25 mutant. S2308 also activated p38 phosphorylation protein, extracellular-regulated protein kinases (ERK, and Jun-N-terminal kinase (JNK from MAPK signal pathway. 2308ΔOmp25 could not activate p38, ERK, and JNK branches. Immunohistochemistry experiments showed that S2308 was able to activate phosphorylation of p38 and ERK in BABL/c mice. However, 2308ΔOmp25 could weakly activate phosphorylation of p38 and ERK. These results suggest that Omp25 played an important role in the process of Brucella activation of the MAPK signal pathway.

  5. Protein composition of catalytically active human telomerase from immortal cells

    DEFF Research Database (Denmark)

    Cohen, Scott B; Graham, Mark E; Lovrecz, George O

    2007-01-01

    Telomerase is a ribonucleoprotein enzyme complex that adds 5'-TTAGGG-3' repeats onto the ends of human chromosomes, providing a telomere maintenance mechanism for approximately 90% of human cancers. We have purified human telomerase approximately 10(8)-fold, with the final elution dependent on th...

  6. Activation of ERK mitogen-activated protein kinase in human cells by the mycotoxin patulin

    International Nuclear Information System (INIS)

    Wu, T.-S.; Yu, F.-Y.; Su, C.-C.; Kan, J.-C.; Chung, C.-P.; Liu, B.-H.

    2005-01-01

    Patulin (PAT), a mycotoxin produced by certain species of Penicillium and Aspergillus, is often detectable in moldy fruits and their derivative products. PAT led to a concentration-dependent and time-dependent increase in phosphorylation of extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) in human embryonic kidney (HEK293) cells, human peripheral blood mononuclear cells (PBMCs), and Madin-Darby canine kidney (MDCK) cells. Exposure of HEK293 cells to concentrations above 5 μM PAT for 30 min induced ERK1/2 phosphorylation; activation of ERK1/2 was also observed after 24 h incubation with 0.05 μM of PAT. Treatment of human PBMCs for 30 min with 30 μM PAT dramatically increased the phosphorylated ERK1/2 levels. Both MEK1/2 inhibitors, U0126 and PD98059, suppressed ERK1/2 activation in either HEK293 or MDCK cells. In HEK293 cells, U0126-mediated inhibition of PAT-induced ERK1/2 phosphorylation resulted in a significant decrease in levels of DNA damage, expressed as tail moment values, in the single cell gel electrophoresis assay. Conversely, U0126 did not affect cell viability, lactate dehydrogenase release, and the DNA synthesis rate in PAT-treated cultures. Exposure of HEK293 cells for 90 min to 15 μM PAT elevated the levels of early growth response gene-1 (egr-1) mRNA, but not of c-fos, fosB, and junB mRNAs. These results indicate that in human cells, PAT causes a rapid and persistent activation of ERK1/2 and this signaling pathway plays an important role in mediating PAT-induced DNA damage and egr-1 gene expression

  7. Elemental analysis of human serum and serum protein fractions by thermal neutron activation

    International Nuclear Information System (INIS)

    Woittiez, J.R.W.

    1984-01-01

    Some applications of thermal neutron activation for the determination of elemental contents in human serum and human serum protein fractions are presented. Firstly total serum is dealt with, secondly serum protein fractions obtained by gel filtration are described. A brief review on the role of (trace) elements in human health and disease and a compilation of literature data for elemental contents in human serum, as obtained by neutron activation techniques, are given. The most important sources of statistical and systematic errors are evaluated. Results for the contents of sodium, potassium, magnesium, bromine, iron, copper, zinc, selenium, rubidium, cesium and antimony in serum are given, with emphasis on control of accuracy and precision. The possible relation between selenium in blood and cancer occurrence in humans is discussed. The results of elemental analyses from cancer patients and from a patient receiving a cytostatic treatment are presented. A survey of literature results for the determination of protein-bound elemental contents in serum is presented. Subsequently, results from a study on the behaviour of elements during gel filtration are discussed. Gel-element and protein-element interactions are studied. Finally the protein-bound occurrence of trace elements in human serum is determined by gel filtration and neutron activation analysis. Results for both desalting and fractionation are given, for the elements bromine, copper, manganese, vanadium, selenium, zinc, rubidium, iron and iodine. (Auth.)

  8. Activation of human natural killer cells by the soluble form of cellular prion protein

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Yeon-Jae [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Hafis Clinic, Seoul (Korea, Republic of); Sung, Pil Soo; Jang, Young-Soon; Choi, Young Joon [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Park, Bum-Chan [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Park, Su-Hyung [Laboratory of Translational Immunology and Vaccinology, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Park, Young Woo [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Shin, Eui-Cheol, E-mail: ecshin@kaist.ac.kr [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of)

    2015-08-21

    Cellular prion protein (PrP{sup C}) is widely expressed in various cell types, including cells of the immune system. However, the specific roles of PrP{sup C} in the immune system have not been clearly elucidated. In the present study, we investigated the effects of a soluble form of recombinant PrP{sup C} protein on human natural killer (NK) cells. Recombinant soluble PrP{sup C} protein was generated by fusion of human PrP{sup C} with the Fc portion of human IgG{sub 1} (PrP{sup C}-Fc). PrP{sup C}-Fc binds to the surface of human NK cells, particularly to CD56{sup dim} NK cells. PrP{sup C}-Fc induced the production of cytokines and chemokines and the degranulation of granzyme B from NK cells. In addition, PrP{sup C}-Fc facilitated the IL-15-induced proliferation of NK cells. PrP{sup C}-Fc induced phosphorylation of ERK-1/2 and JNK in NK cells, and inhibitors of the ERK or the JNK pathways abrogated PrP{sup C}-Fc-induced cytokine production in NK cells. In conclusion, the soluble form of recombinant PrP{sup C}-Fc protein activates human NK cells via the ERK and JNK signaling pathways. - Highlights: • Recombinant soluble PrP{sup C} (PrP{sup C}-Fc) was generated by fusion of human PrP{sup C} with IgG1 Fc portion. • PrP{sup C}-Fc protein induces the production of cytokines and degranulation from human NK cells. • PrP{sup C}-Fc protein enhances the IL-15-induced proliferation of human NK cells. • PrP{sup C}-Fc protein activates human NK cells via the ERK and JNK signaling pathways.

  9. Activation of human natural killer cells by the soluble form of cellular prion protein

    International Nuclear Information System (INIS)

    Seong, Yeon-Jae; Sung, Pil Soo; Jang, Young-Soon; Choi, Young Joon; Park, Bum-Chan; Park, Su-Hyung; Park, Young Woo; Shin, Eui-Cheol

    2015-01-01

    Cellular prion protein (PrP C ) is widely expressed in various cell types, including cells of the immune system. However, the specific roles of PrP C in the immune system have not been clearly elucidated. In the present study, we investigated the effects of a soluble form of recombinant PrP C protein on human natural killer (NK) cells. Recombinant soluble PrP C protein was generated by fusion of human PrP C with the Fc portion of human IgG 1 (PrP C -Fc). PrP C -Fc binds to the surface of human NK cells, particularly to CD56 dim NK cells. PrP C -Fc induced the production of cytokines and chemokines and the degranulation of granzyme B from NK cells. In addition, PrP C -Fc facilitated the IL-15-induced proliferation of NK cells. PrP C -Fc induced phosphorylation of ERK-1/2 and JNK in NK cells, and inhibitors of the ERK or the JNK pathways abrogated PrP C -Fc-induced cytokine production in NK cells. In conclusion, the soluble form of recombinant PrP C -Fc protein activates human NK cells via the ERK and JNK signaling pathways. - Highlights: • Recombinant soluble PrP C (PrP C -Fc) was generated by fusion of human PrP C with IgG1 Fc portion. • PrP C -Fc protein induces the production of cytokines and degranulation from human NK cells. • PrP C -Fc protein enhances the IL-15-induced proliferation of human NK cells. • PrP C -Fc protein activates human NK cells via the ERK and JNK signaling pathways

  10. Influence of Prolonged Storage Process, Pasteurization, and Heat Treatment on Biologically-active Human Milk Proteins

    Directory of Open Access Journals (Sweden)

    Jih-Chin Chang

    2013-12-01

    Conclusion: Various freezing/heating/pasteurization processes applied to human milk prior to delivery to neonates could affect the concentration of immunomodulatory proteins, especially lactoferrin, secretory immunoglobulin A, and lysozyme. Leptin was unaffected by the various handling processes tested. Fresh milk was found to be the best food for neonates. Further studies are warranted to evaluate the functional activity of these proteins and their effects on infants' immunological status.

  11. Protective features of resveratrol on human spermatozoa cryopreservation may be mediated through 5' AMP-activated protein kinase activation.

    Science.gov (United States)

    Shabani Nashtaei, M; Amidi, F; Sedighi Gilani, M A; Aleyasin, A; Bakhshalizadeh, Sh; Naji, M; Nekoonam, S

    2017-03-01

    Biochemical and physical modifications during the freeze-thaw process adversely influence the restoration of energy-dependent sperm functions required for fertilization. Resveratrol, a phytoalexin, has been introduced to activate 5' AMP-activated protein kinase which is a cell energy sensor and a cell metabolism regulator. The cryoprotection of resveratrol on sperm cryoinjury via activation of AMP-activated protein kinase also remains to be elucidated. Our aim, thus, was to investigate: (i) the presence and intracellular localization of AMP-activated protein kinase protein; (ii) whether resveratrol may exert a protective effect on certain functional properties of fresh and post-thaw human spermatozoa through modulation of AMP-activated protein kinase. Spermatozoa from normozoospermic men were incubated with or without different concentrations of Compound C as an AMP-activated protein kinase inhibitor or resveratrol as an AMP-activated protein kinase activator for different lengths of time and were then cryopreserved. AMP-activated protein kinase is expressed essentially in the entire flagellum and the post-equatorial region. Viability of fresh spermatozoa was not significantly affected by the presence of Compound C or resveratrol. However, although Compound C caused a potent inhibition of spermatozoa motility parameters, resveratrol did not induce negative effect, except a significant reduction in motility at 25 μm for 1 h. Furthermore, resveratrol significantly increased AMP-activated protein kinase phosphorylation and mitochondrial membrane potential and decreased reactive oxygen species and apoptosis-like changes in frozen-thawed spermatozoa. Nevertheless, it was not able to compensate decreased sperm viability and motility parameters following cryopreservation. In contrast, Compound C showed opposite effects to resveratrol on AMP-activated protein kinase phosphorylation, reactive oxygen species, apoptosis-like changes, mitochondrial membrane potential, and

  12. Human Protein C produces anticoagulation and increased fibrinolytic activity in the cat

    International Nuclear Information System (INIS)

    Burdick, M.D.; Schaub, R.G.

    1986-01-01

    The effect of activated human Protein C (PCa) infusion on the coagulation and fibrinolytic systems of the Nembutal anesthetized cat was assessed. Human Protein C was activated by incubation with thrombin or by passage over a column of thrombin immobilized on CNBr Sepharose 4B. Cats were given bolus i.v. injections of either vehicle or PCa in a dose range of 3-16 μg/mL of calculated whole body volume. Citrated blood samples (9:1) were taken from a femoral vein prior to and at 5, 10, 20, 30, 60, 120, and 180 min. after PCa. Activated partial thromboplastin time (APTT), thrombin time (TT) euglobulin clot lysis (ECLT) and I-125 fibrin release (FR) was measured. Vehicle treated cats had no change in any parameter. PCa produced a dose and time dependent prolongation of APTT while TT was unchanged. Anticoagulation was evident immediately after PCa infusion and began to normalize within 20 min. Fibrinolytic activity measured by ECLT and FR was also stimulated by PCa but was not evident until 40-60 minutes after PCa injection. The results show that human PCa induces anticoagulation effects in the cat similar to other species. However, stimulation of fibrinolysis requires a longer period of time before expression. This delay of fibrinolytic stimulation should be considered when assessing the effects of human Protein C in other species

  13. Antimicrobial Activity of Human Prion Protein Is Mediated by Its N-Terminal Region

    OpenAIRE

    Pasupuleti, Mukesh; Roupe, Markus; Rydeng?rd, Victoria; Surewicz, Krystyna; Surewicz, Witold K.; Chalupka, Anna; Malmsten, Martin; S?rensen, Ole E.; Schmidtchen, Artur

    2009-01-01

    BACKGROUND: Cellular prion-related protein (PrP(c)) is a cell-surface protein that is ubiquitously expressed in the human body. The multifunctionality of PrP(c), and presence of an exposed cationic and heparin-binding N-terminus, a feature characterizing many antimicrobial peptides, made us hypothesize that PrP(c) could exert antimicrobial activity. METHODOLOGY AND PRINCIPAL FINDINGS: Intact recombinant PrP exerted antibacterial and antifungal effects at normal and low pH. Studies employing r...

  14. Reduced influenza viral neutralizing activity of natural human trimers of surfactant protein D

    DEFF Research Database (Denmark)

    Hartshorn, Kevan L; White, Mitchell R; Tecle, Tesfaldet

    2007-01-01

    BACKGROUND: Surfactant protein D (SP-D) plays important roles in innate host defense against influenza A virus (IAV) infection. Common human polymorphisms of SP-D have been found in many human populations and associated with increased risk of certain infections. We recently reported that the Thr...... on the CRD of SP-D were found to have differing effects on antiviral activity. Using an mAb that did not interfere with antiviral activity of SP-D, we confirm that natural SP-D trimers had reduced ability to bind to IAV. In addition, the trimers had reduced ability to neutralize IAV as compared to natural...... indicate that a common human polymorphic form of SP-D may modulate host defense against IAV and give impetus to clinical studies correlating this genotype with risk for IAV infection in susceptible groups. We also show that mAbs directed against different areas on the carbohydrate recognition domain of SP...

  15. Residual endotoxin contaminations in recombinant proteins are sufficient to activate human CD1c+ dendritic cells.

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    Harald Schwarz

    Full Text Available Many commercially available recombinant proteins are produced in Escherichia coli, and most suppliers guarantee contamination levels of less than 1 endotoxin unit (EU. When we analysed commercially available proteins for their endotoxin content, we found contamination levels in the same range as generally stated in the data sheets, but also some that were higher. To analyse whether these low levels of contamination have an effect on immune cells, we stimulated the monocytic cell line THP-1, primary human monocytes, in vitro differentiated human monocyte-derived dendritic cells, and primary human CD1c+ dendritic cells (DCs with very low concentrations of lipopolysaccharide (LPS; ranging from 0.002-2 ng/ml. We show that CD1c+ DCs especially can be activated by minimal amounts of LPS, equivalent to the levels of endotoxin contamination we detected in some commercially available proteins. Notably, the enhanced endotoxin sensitivity of CD1c+ DCs was closely correlated with high CD14 expression levels observed in CD1c+ DCs that had been maintained in cell culture medium for 24 hours. When working with cells that are particularly sensitive to LPS, even low endotoxin contamination may generate erroneous data. We therefore recommend that recombinant proteins be thoroughly screened for endotoxin contamination using the limulus amebocyte lysate test, fluorescence-based assays, or a luciferase based NF-κB reporter assay involving highly LPS-sensitive cells overexpressing TLR4, MD-2 and CD14.

  16. Human activated protein C variants in a rat model of arterial thrombosis

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    Dahlbäck Björn

    2008-10-01

    Full Text Available Abstract Background Activated protein C (APC inhibits coagulation by degrading activated factor V (FVa and factor VIII (FVIIIa, protein S (PS functioning as a cofactor to APC. Methods By mutagenesis of the vitamin K-dependent Gla domain of APC, we have recently created an APC variant having enhanced anticoagulant activity due to increased affinity for negatively charged phospholipid membranes. In the present study, the potential antithrombotic effects of this APC variant, and of a variant APC that is additionally mutated in the serine protease domain, have been evaluated in a blind randomized study in a rat model of arterial thrombosis. In this model, we have previously found the combination of bovine APC and PS to be highly antithrombotic. Four treatment groups each containing 10 rats were, in a blind random fashion, given intravenous bolus injections of wild-type or mutant variants of APC (0.8 mg/kg together with human PS (0.6 mg/kg or human PS (0.6 mg/kg alone. A control group with 20 animals where given vehicle only. Results A trend to increased patency rates was noted in a group receiving one of the APC variants, but it did not reach statistical significance. Conclusion In conclusion, administration of human APC variants having enhanced anticoagulant efficacy together with human PS in a rat model of arterial thrombosis did not give an efficient antithrombotic effect. The lack of effect may be due to species-specific differences between the human protein C system and the rat hemostatic system.

  17. Synthesis and processing of sphingolipid activator protein-2 (SAP-2) in cultured human fibroblasts

    International Nuclear Information System (INIS)

    Fujibayashi, S.; Wenger, D.A.

    1986-01-01

    Sphingolipid activator proteins (SAP) are relatively small molecular weight proteins that stimulate the enzymatic hydrolysis of sphingolipids in the presence of specific lysosomal hydrolases. SAP-2 has previously been demonstrated to activate the hydrolysis of glucosylceramide, galactosylceramide, and, possibly, sphingomyelin. Using monospecific rabbit antibodies against human spleen SAP-2, the synthesis and processing of SAP-2 were studied in cultured human fibroblasts. When [ 35 S]methionine was presented in the medium to control human cells for 4 h, five major areas of radiolabeling were found. These had apparent molecular weights of 73,000, 68,000, 50,000, 12,000, and 9000. Further studies indicated that the major extracellular product in normal cells given NH4Cl along with the [ 35 S]methionine and in medium from cultures from patients with I cell disease had an apparent molecular weight of 73,000. The Mr = 68,000 and 73,000 species can be converted to a species with an apparent molecular weight of 50,000 by the action of endoglycosidase F. After labeling cells for 1 h followed by a 1-h chase, the Mr = 12,000 and 9000 species appear. Treatment of the immunoprecipitated mixture with endoglycosidase F resulted in conversion of these species to one band with an apparent molecular weight of 7600. These studies indicate that this relatively low molecular weight protein is rapidly synthesized from a relatively large molecular weight highly glycosylated precursor

  18. Activation of protein kinase A and exchange protein directly activated by cAMP promotes adipocyte differentiation of human mesenchymal stem cells

    DEFF Research Database (Denmark)

    Jia, Bingbing; Madsen, Lise; Petersen, Rasmus Koefoed

    2012-01-01

    ) and exchange protein directly activated by cAMP (Epac) in adipocyte conversion of human mesenchymal stem cells derived from adipose tissue (hMADS). We show that cAMP signaling involving the simultaneous activation of both PKA- and Epac-dependent signaling is critical for this process even in the presence......Human mesenchymal stem cells are primary multipotent cells capable of differentiating into several cell types including adipocytes when cultured under defined in vitro conditions. In the present study we investigated the role of cAMP signaling and its downstream effectors, protein kinase A (PKA...... results emphasize the need for cAMP signaling in concert with treatment with a PPARγ or PPARδ agonist to secure efficient adipocyte differentiation of human hMADS mesenchymal stem cells....

  19. Antimicrobial activity of human prion protein is mediated by its N-terminal region.

    Directory of Open Access Journals (Sweden)

    Mukesh Pasupuleti

    Full Text Available BACKGROUND: Cellular prion-related protein (PrP(c is a cell-surface protein that is ubiquitously expressed in the human body. The multifunctionality of PrP(c, and presence of an exposed cationic and heparin-binding N-terminus, a feature characterizing many antimicrobial peptides, made us hypothesize that PrP(c could exert antimicrobial activity. METHODOLOGY AND PRINCIPAL FINDINGS: Intact recombinant PrP exerted antibacterial and antifungal effects at normal and low pH. Studies employing recombinant PrP and N- and C-terminally truncated variants, as well as overlapping peptide 20mers, demonstrated that the antimicrobial activity is mediated by the unstructured N-terminal part of the protein. Synthetic peptides of the N-terminus of PrP killed the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, and the Gram-positive Bacillus subtilis and Staphylococcus aureus, as well as the fungus Candida parapsilosis. Fluorescence studies of peptide-treated bacteria, paired with analysis of peptide effects on liposomes, showed that the peptides exerted membrane-breaking effects similar to those seen after treatment with the "classical" human antimicrobial peptide LL-37. In contrast to LL-37, however, no marked helix induction was detected for the PrP-derived peptides in presence of negatively charged (bacteria-mimicking liposomes. PrP furthermore showed an inducible expression during wounding of human skin ex vivo and in vivo, as well as stimulation of keratinocytes with TGF-alpha in vitro. CONCLUSIONS: The demonstration of an antimicrobial activity of PrP, localisation of its activity to the N-terminal and heparin-binding region, combined with results showing an increased expression of PrP during wounding, indicate that PrPs could have a previously undisclosed role in host defense.

  20. Influence of prolonged storage process, pasteurization, and heat treatment on biologically-active human milk proteins.

    Science.gov (United States)

    Chang, Jih-Chin; Chen, Chao-Huei; Fang, Li-Jung; Tsai, Chi-Ren; Chang, Yu-Chuan; Wang, Teh-Ming

    2013-12-01

    The bioactive proteins in human milk may be influenced by prolonged storage process, pasteurization, and heat treatment. This study was conducted to evaluate the effects of these procedures. Three forms of human milk - freshly expressed, frozen at -20°C for a prolonged duration, and pasteurized milk - were collected from 14 healthy lactating mothers and a milk bank. The concentrations of major bioactive proteins (secretory immunoglobulin A, lactoferrin, lysozyme, and leptin) were quantified using enzyme-linked immunosorbent assay kits. Changes in these proteins by heat treatment at 40°C or 60°C for 30 minutes were further evaluated. The mean concentrations of lactoferrin and secretory immunoglobulin A were significantly reduced by 66% and 25.9%, respectively, in pasteurized milk compared with those in freshly-expressed milk. Heat treatment at 40°C or 60°C did not cause significant changes in lactoferrin and secretory immunoglobulin A, but there was an apparent increase in lysozyme (p = 0.016). There were no significant differences in leptin level among these three forms of milk prior to (p = 0.153) or after heat treatment (p = 0.053). Various freezing/heating/pasteurization processes applied to human milk prior to delivery to neonates could affect the concentration of immunomodulatory proteins, especially lactoferrin, secretory immunoglobulin A, and lysozyme. Leptin was unaffected by the various handling processes tested. Fresh milk was found to be the best food for neonates. Further studies are warranted to evaluate the functional activity of these proteins and their effects on infants' immunological status. Copyright © 2013. Published by Elsevier B.V.

  1. AMP-activated protein kinase activation mediates CCL3-induced cell migration and matrix metalloproteinase-2 expression in human chondrosarcoma

    Science.gov (United States)

    2013-01-01

    Chemokine (C-C motif) ligand 3 (CCL3), also known as macrophage inflammatory protein-1α, is a cytokine involved in inflammation and activation of polymorphonuclear leukocytes. CCL3 has been detected in infiltrating cells and tumor cells. Chondrosarcoma is a highly malignant tumor that causes distant metastasis. However, the effect of CCL3 on human chondrosarcoma metastasis is still unknown. Here, we found that CCL3 increased cellular migration and expression of matrix metalloproteinase (MMP)-2 in human chondrosarcoma cells. Pre-treatment of cells with the MMP-2 inhibitor or transfection with MMP-2 specific siRNA abolished CCL3-induced cell migration. CCL3 has been reported to exert its effects through activation of its specific receptor, CC chemokine receptor 5 (CCR5). The CCR5 and AMP-activated protein kinase (AMPK) inhibitor or siRNA also attenuated CCL3-upregulated cell motility and MMP-2 expression. CCL3-induced expression of MMP-2 and migration were also inhibited by specific inhibitors, and inactive mutants of AMPK, p38 mitogen activated protein kinase (p38 or p38-MAPK), and nuclear factor κB (NF-κB) cascades. On the other hand, CCL3 treatment demonstrably activated AMPK, p38, and NF-κB signaling pathways. Furthermore, the expression levels of CCL3, CCR5, and MMP-2 were correlated in human chondrosarcoma specimens. Taken together, our results indicate that CCL3 enhances the migratory ability of human chondrosarcoma cells by increasing MMP-2 expression via the CCR5, AMPK, p38, and NF-κB pathways. PMID:24047437

  2. INHIBITION OF PROTEIN TYROSINE PHOSPHATASE ACTIVITY MEDIATES EPIDERMAL GROWTH FACTOR RECEPTOR SIGNALING IN HUMAN AIRWAY EPITHELIAL CELLS

    Science.gov (United States)

    Epidemiological studies have implicated zinc in the toxicity of ambient particulate matter (PM) inhalation. We previously showed that exposure to metal-laden PM inhibits protein tyrosine phosphatase (PTP) activity in human primary bronchial epithelial cells (HAEC) and leads t...

  3. Pharmacological characterization of receptor-activity-modifying proteins (RAMPs) and the human calcitonin receptor.

    Science.gov (United States)

    Armour, S L; Foord, S; Kenakin, T; Chen, W J

    1999-12-01

    Receptor-activity-modifying proteins (RAMPs) are a family of single transmembrane domain proteins shown to be important for the transport and ligand specificity of the calcitonin gene-related peptide (CGRP) receptor. In this report, we describe the analysis of pharmacological properties of the human calcitonin receptor (hCTR) coexpressed with different RAMPs with the use of the Xenopus laevis melanophore expression system. We show that coexpression of RAMP3 with human calcitonin receptor changed the relative potency of hCTR to human calcitonin (hCAL) and rat amylin. RAMP1 and RAMP2, in contrast, had little effect on the change of hCTR potency to hCAL or rat amylin. When coexpressed with RAMP3, hCTR reversed the relative potency by a 3.5-fold loss in sensitivity to hCAL and a 19-fold increase in sensitivity to rat amylin. AC66, an inverse agonist, produced apparent simple competitive antagonism of hCAL and rat amylin, as indicated by linear Schild regressions. The potency of AC66 was changed in the blockade of rat amylin but not hCAL responses with RAMP3 coexpression. The mean pK(B) for AC66 to hCAL was 9.4 +/- 0.3 without RAMP3 and 9.45 +/- 0.07 with RAMP3. For the antagonism of AC66 to rat amylin, the pK(B) was 9.25 +/- 0.15 without RAMP3 and 8.2 +/- 0.35 with RAMP3. The finding suggests that RAMP3 might modify the active states of calcitonin receptor in such a way as to create a new receptor phenotype that is "amylin-like." Irrespective of the physiological association of the new receptor species, the finding that a coexpressed membrane protein can completely change agonist and antagonist affinities for a receptor raises implications for screening in recombinant receptor systems.

  4. Protein C inhibitor acts as a procoagulant by inhibiting the thrombomodulin-induced activation of protein C in human plasma

    NARCIS (Netherlands)

    Elisen, M. G.; von dem Borne, P. A.; Bouma, B. N.; Meijers, J. C.

    1998-01-01

    Protein C inhibitor (PCI), which was originally identified as an inhibitor of activated protein C, also efficiently inhibits coagulation factors such as factor Xa and thrombin. Recently it was found, using purified proteins, that the anticoagulant thrombin-thrombomodulin complex was also inhibited

  5. Dissecting the role of AMP-activated protein kinase in human diseases

    Institute of Scientific and Technical Information of China (English)

    Jin Li; Liping Zhong; Fengzhong Wang; Haibo Zhu

    2017-01-01

    AMP-activated protein kinase (AMPK),known as a sensor and a master of cellular energy balance,integrates various regulatory signals including anabolic and catabolic metabolic processes.Accompanying the application of genetic methods and a plethora of AMPK agonists,rapid progress has identified AMPK as an attractive therapeutic target for several human diseases,such as cancer,type 2 diabetes,atherosclerosis,myocardial ischemia/reperfusion injury and neurodegenerative disease.The role of AMPK in metabolic and energetic modulation both at the intracellular and whole body levels has been reviewed elsewhere.In the present review,we summarize and update the paradoxical role of AMPK implicated in the diseases mentioned above and put forward the challenge encountered.Thus it will be expected to provide important clues for exploring rational methods of intervention in human diseases.

  6. Quantitation of fibroblast activation protein (FAP-specific protease activity in mouse, baboon and human fluids and organs

    Directory of Open Access Journals (Sweden)

    Fiona M. Keane

    2014-01-01

    Full Text Available The protease fibroblast activation protein (FAP is a specific marker of activated mesenchymal cells in tumour stroma and fibrotic liver. A specific, reliable FAP enzyme assay has been lacking. FAP's unique and restricted cleavage of the post proline bond was exploited to generate a new specific substrate to quantify FAP enzyme activity. This sensitive assay detected no FAP activity in any tissue or fluid of FAP gene knockout mice, thus confirming assay specificity. Circulating FAP activity was ∼20- and 1.3-fold less in baboon than in mouse and human plasma, respectively. Serum and plasma contained comparable FAP activity. In mice, the highest levels of FAP activity were in uterus, pancreas, submaxillary gland and skin, whereas the lowest levels were in brain, prostate, leukocytes and testis. Baboon organs high in FAP activity included skin, epididymis, bladder, colon, adipose tissue, nerve and tongue. FAP activity was greatly elevated in tumours and associated lymph nodes and in fungal-infected skin of unhealthy baboons. FAP activity was 14- to 18-fold greater in cirrhotic than in non-diseased human liver, and circulating FAP activity was almost doubled in alcoholic cirrhosis. Parallel DPP4 measurements concorded with the literature, except for the novel finding of high DPP4 activity in bile. The new FAP enzyme assay is the first to be thoroughly characterised and shows that FAP activity is measurable in most organs and at high levels in some. This new assay is a robust tool for specific quantitation of FAP enzyme activity in both preclinical and clinical samples, particularly liver fibrosis.

  7. Oral glucose ingestion attenuates exercise-induced activation of 5'-AMP-activated protein kinase in human skeletal muscle

    DEFF Research Database (Denmark)

    Åkerström, Thorbjörn; Birk, Jesper Bratz; Klein, Ditte Kjærsgaard

    2006-01-01

    5'-AMP-activated protein kinase (AMPK) has been suggested to be a 'metabolic master switch' regulating various aspects of muscle glucose and fat metabolism. In isolated rat skeletal muscle, glucose suppresses the activity of AMPK and in human muscle glycogen loading decreases exercise-induced AMPK...... activation. We hypothesized that oral glucose ingestion during exercise would attenuate muscle AMPK activation. Nine male subjects performed two bouts of one-legged knee-extensor exercise at 60% of maximal workload. The subjects were randomly assigned to either consume a glucose containing drink or a placebo...... drink during the two trials. Muscle biopsies were taken from the vastus lateralis before and after 2 h of exercise. Plasma glucose was higher (6.0 +/- 0.2 vs. 4.9 +/- 0.1 mmol L-1, P

  8. Knockdown of MAGEA6 Activates AMP-Activated Protein Kinase (AMPK) Signaling to Inhibit Human Renal Cell Carcinoma Cells.

    Science.gov (United States)

    Ye, Xueting; Xie, Jing; Huang, Hang; Deng, Zhexian

    2018-01-01

    Melanoma antigen A6 (MAGEA6) is a cancer-specific ubiquitin ligase of AMP-activated protein kinase (AMPK). The current study tested MAGEA6 expression and potential function in renal cell carcinoma (RCC). MAGEA6 and AMPK expression in human RCC tissues and RCC cells were tested by Western blotting assay and qRT-PCR assay. shRNA method was applied to knockdown MAGEA6 in human RCC cells. Cell survival and proliferation were tested by MTT assay and BrdU ELISA assay, respectively. Cell apoptosis was tested by the TUNEL assay and single strand DNA ELISA assay. The 786-O xenograft in nude mouse model was established to test RCC cell growth in vivo. MAGEA6 is specifically expressed in RCC tissues as well as in the established (786-O and A498) and primary human RCC cells. MAGEA6 expression is correlated with AMPKα1 downregulation in RCC tissues and cells. It is not detected in normal renal tissues nor in the HK-2 renal epithelial cells. MAGEA6 knockdown by targeted-shRNA induced AMPK stabilization and activation, which led to mTOR complex 1 (mTORC1) in-activation and RCC cell death/apoptosis. AMPK inhibition, by AMPKα1 shRNA or the dominant negative AMPKα1 (T172A), almost reversed MAGEA6 knockdown-induced RCC cell apoptosis. Conversely, expression of the constitutive-active AMPKα1 (T172D) mimicked the actions by MAGEA6 shRNA. In vivo, MAGEA6 shRNA-bearing 786-O tumors grew significantly slower in nude mice than the control tumors. AMPKα1 stabilization and activation as well as mTORC1 in-activation were detected in MAGEA6 shRNA tumor tissues. MAGEA6 knockdown inhibits human RCC cells via activating AMPK signaling. © 2018 The Author(s). Published by S. Karger AG, Basel.

  9. Structure of the human protein kinase MPSK1 reveals an atypical activation loop architecture.

    Science.gov (United States)

    Eswaran, Jeyanthy; Bernad, Antonio; Ligos, Jose M; Guinea, Barbara; Debreczeni, Judit E; Sobott, Frank; Parker, Sirlester A; Najmanovich, Rafael; Turk, Benjamin E; Knapp, Stefan

    2008-01-01

    The activation segment of protein kinases is structurally highly conserved and central to regulation of kinase activation. Here we report an atypical activation segment architecture in human MPSK1 comprising a beta sheet and a large alpha-helical insertion. Sequence comparisons suggested that similar activation segments exist in all members of the MPSK1 family and in MAST kinases. The consequence of this nonclassical activation segment on substrate recognition was studied using peptide library screens that revealed a preferred substrate sequence of X-X-P/V/I-phi-H/Y-T*-N/G-X-X-X (phi is an aliphatic residue). In addition, we identified the GTPase DRG1 as an MPSK1 interaction partner and specific substrate. The interaction domain in DRG1 was mapped to the N terminus, leading to recruitment and phosphorylation at Thr100 within the GTPase domain. The presented data reveal an atypical kinase structural motif and suggest a role of MPSK1 regulating DRG1, a GTPase involved in regulation of cellular growth.

  10. Evolutionarily conserved regions of the human c-myc protein can be uncoupled from transforming activity

    International Nuclear Information System (INIS)

    Sarid, J.; Halazonetis, T.D.; Murphy, W.; Leder, P.

    1987-01-01

    The myc family of oncogenes contains coding sequences that have been preserved in different species for over 400 million years. This conservation (which implies functional selection) is broadly represented throughout the C-terminal portion of the human c-myc protein but is largely restricted to three cluster of amino acid sequences in the N-terminal region. The authors have examined the role that the latter three regions of the c-myc protein might play in the transforming function of the c-myc gene. Several mutations, deletions and frameshifts, were introduced into the c-myc gene, and these mutant genes were tested for their ability to collaborate with the EJ-ras oncogene to transform rat embryo fibroblasts. Complete elimination of the first two N-terminal conserved segments abolished transforming activity. In contrast, genes altered in a portion of the second or the entire third conserved segment retained their transforming activity. Thus, the latter two segments are not required for the transformation process, suggesting that they serve another function related only to the normal expression of the c-myc gene

  11. Activated effects of parathyroid hormone-related protein on human hepatic stellate cells.

    Directory of Open Access Journals (Sweden)

    Fen-Fen Liang

    Full Text Available BACKGROUND & AIMS: After years of experiments and clinical studies, parathyroid hormone-related protein(PTHrP has been shown to be a bone formation promoter that elicits rapid effects with limited adverse reaction. Recently, PTHrP was reported to promote fibrosis in rat kidney in conjunction with transforming growth factor-beta1 (TGF-β1, which is also a fibrosis promoter in liver. However, the effect of PTHrP in liver has not been determined. In this study, the promoting actions of PTHrP were first investigated in human normal hepatic stellate cells (HSC and LX-2 cell lines. METHODS: TGF-β1, alpha-smooth muscle actin (α-SMA, matrix metalloproteinase 2 (MMP-2, and collagen I mRNA were quantified by real-time polymerase chain reaction (PCR after HSCs or LX-2 cells were treated with PTHrP(1-36 or TGF-β1. Protein levels were also assessed by western-blot analysis. Alpha-SMA were also detected by immunofluorescence, and TGF-β1 secretion was measured with enzyme-linked immunosorbent assay (ELISA of HSC cell culture media. RESULTS: In cultured human HSCs, mRNA and protein levels of α-SMA, collagen I, MMP-2, and TGF-β1 were increased by PTHrP treatment. A similar increasing pattern was also observed in LX-2 cells. Moreover, PTHrP significantly increased TGF-β1 secretion in cultured media from HSCs. CONCLUSIONS: PTHrP activated HSCs and promoted the fibrosis process in LX-2 cells. These procedures were probably mediated via TGF-β1, highlighting the potential effects of PTHrP in the liver.

  12. Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers, Additives and Detergents Solutions for Recombinant Protein Production.

    Directory of Open Access Journals (Sweden)

    Raheem Ullah

    Full Text Available Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally employed for purification and stabilization of proteins, hence, necessitate their removal by tedious and time-consuming procedures before proteolysis can occur. To address this issue, we examined the effect of elution buffers used for common affinity based purifications, salt ions, stability/solubility and reducing agents, and detergents on the activity of the human rhinovirus 3C protease using three different fusion proteins at 4°C, a temperature of choice for purification of many proteins. The results show that the human rhinovirus 3C protease performs better at 4°C than the frequently used tobacco etch virus protease and its activity was insensitive to most of the experimental conditions tested. Though number of fusion proteins tested is limited, we expect that these finding will facilitate the use of the human rhinovirus 3C protease in recombinant protein production for pharmaceutical and biotechnological applications.

  13. Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers, Additives and Detergents Solutions for Recombinant Protein Production.

    Science.gov (United States)

    Ullah, Raheem; Shah, Majid Ali; Tufail, Soban; Ismat, Fouzia; Imran, Muhammad; Iqbal, Mazhar; Mirza, Osman; Rhaman, Moazur

    2016-01-01

    Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally employed for purification and stabilization of proteins, hence, necessitate their removal by tedious and time-consuming procedures before proteolysis can occur. To address this issue, we examined the effect of elution buffers used for common affinity based purifications, salt ions, stability/solubility and reducing agents, and detergents on the activity of the human rhinovirus 3C protease using three different fusion proteins at 4°C, a temperature of choice for purification of many proteins. The results show that the human rhinovirus 3C protease performs better at 4°C than the frequently used tobacco etch virus protease and its activity was insensitive to most of the experimental conditions tested. Though number of fusion proteins tested is limited, we expect that these finding will facilitate the use of the human rhinovirus 3C protease in recombinant protein production for pharmaceutical and biotechnological applications.

  14. ZNF328, a novel human zinc-finger protein, suppresses transcriptional activities of SRE and AP-1

    International Nuclear Information System (INIS)

    Ou Ying; Wang Shenqiu; Cai Zhenyu; Wang Yuequn; Wang Canding; Li Yongqing; Li Fang; Yuan Wuzhou; Liu Bisheng; Wu Xiushan; Liu Mingyao

    2005-01-01

    The zinc finger proteins containing the Kruppel-associated box domain (KRAB-ZFPs) are the single largest class of transcription factors in human genome. Many of the KRAB-ZFPs are involved in cardiac development or cardiovascular diseases. Here, we have identified a novel human KRAB zinc finger gene, named ZNF328, from the human fetal heart cDNA library. The complete sequence of ZNF328 cDNA contains a 2376-bp open reading frame (ORF) and encodes a 792 amino acid protein with an N-terminal KRAB domain and classical zinc finger C 2 H 2 motifs in the C-terminus. Northern blot analysis indicates that the protein is expressed in most of the examined human adult and embryonic tissues. ZNF328 is a transcription suppressor when fused to Gal-4 DNA-binding domain and cotransfected with VP-16. Overexpression of ZNF328 in COS-7 cells inhibits the transcriptional activities of SRE and AP-1. Deletion analysis with a series of truncated fusion proteins indicates that the KRAB motif is a basal repression domain when cotransfected with VP-16. Similar results were obtained when the truncated fusion proteins were assayed for the transcriptional activities of SRE and AP-1. These results suggest that ZNF328 protein may act as a transcriptional repressor in mitogen-activated protein kinase (MAPK) signaling pathway to mediate cellular functions

  15. Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers, Additives and Detergents Solutions for Recombinant Protein Production

    DEFF Research Database (Denmark)

    Ullah, Raheem; Shah, Majid Ali; Tufail, Soban

    2016-01-01

    stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally employed for purification and stabilization of proteins, hence, necessitate their removal by tedious...

  16. Brominated flame retardants, tetrabromobisphenol A and hexabromocyclododecane, activate mitogen-activated protein kinases (MAPKs) in human natural killer cells.

    Science.gov (United States)

    Cato, Anita; Celada, Lindsay; Kibakaya, Esther Caroline; Simmons, Nadia; Whalen, Margaret M

    2014-12-01

    Natural killer (NK) cells provide a vital surveillance against virally infected cells, tumor cells, and antibody-coated cells through the release of cytolytic mediators and gamma interferon (IFN-γ). Hexabromocyclododecane (HBCD) is a brominated flame retardant used primarily in expanded (EPS) and extruded (XPS) polystyrene foams for thermal insulation in the building and construction industry. Tetrabromobisphenol A (TBBPA) is used both as a reactive and an additive flame retardant in a variety of materials. HBCD and TBBPA contaminate the environment and are found in human blood samples. In previous studies, we have shown that other environmental contaminants, such as the dibutyltin (DBT) and tributyltin (TBT), decrease NK lytic function by activating mitogen-activated protein kinases (MAPKs) in the NK cells. HBCD and TBBPA also interfere with NK cell(s) lytic function. The current study evaluates whether HBCD and/or TBBPA have the capacity to activate MAPKs and MAPK kinases (MAP2Ks). The effects of concentrations of HBCD and TBBPA that inhibited lytic function on the phosphorylation state and total levels of the MAPKs (p44/42, p38, and JNK) and the phosphorylation and total levels of the MAP2Ks (MEK1/2 and MKK3/6) were examined. Results indicate that exposure of human NK cells to 10-0.5 μM HBCD or TBBPA activate MAPKs and MAP2Ks. This HBCD and TBBPA-induced activation of MAPKs may leave them unavailable for activation by virally infected or tumor target cells and thus contributes to the observed decreases in lytic function seen in NK cells exposed to HBCD and TBBPA.

  17. Osteogenic potential of the human bone morphogenetic protein 2 gene activated nanobone putty.

    Science.gov (United States)

    Tian, Xiao-bin; Sun, Li; Yang, Shu-hua; Zhang, Yu-kun; Hu, Ru-yin; Fu, De-hao

    2008-04-20

    Nanobone putty is an injectable and bioresorbable bone substitute. The neutral-pH putty resembles hard bone tissue, does not contain polymers or plasticizers, and is self-setting and nearly isothermic, properties which are helpful for the adhesion, proliferation, and function of bone cells. The aim of this study was to investigate the osteogenic potential of human bone morphogenetic protein 2 (hBMP2) gene activated nanobone putty in inducing ectopic bone formation, and the effects of the hBMP2 gene activated nanobone putty on repairing bone defects. Twenty four Kunming mice were randomly divided into two groups. The nanobone putty + hBMP2 plasmid was injected into the right thigh muscle pouches of the mice (experiment side). The nanobone putty + blank plasmid or nanobone putty was injected into the left thigh muscle pouches of the group 1 (control side 1) or group 2 (control side 2), respectively. The effects of ectopic bone formation were evaluated by radiography, histology, and molecular biology analysis at 2 and 4 weeks after operation. Bilateral 15 mm radial defects were made in forty-eight rabbits. These rabbits were randomly divided into three groups: Group A, nanobone putty + hBMP2 plasmid; Group B, putty + blank plasmid; Group C, nanobone putty only. Six rabbits with left radial defects served as blank controls. The effect of bone repairing was evaluated by radiography, histology, molecular biology, and biomechanical analysis at 4, 8, and 12 weeks after operation. The tissue from the experimental side of the mice expressed hBMP2. Obvious cartilage and island-distributed immature bone formation in implants of the experiment side were observed at 2 weeks after operation, and massive mature bone observed at 4 weeks. No bone formation was observed in the control side of the mice. The ALP activity in the experiment side of the mice was higher than that in the control side. The tissue of Group A rabbits expressed hBMP2 protein and higher ALP level. The new bone

  18. The influence of acute resistance exercise on cyclooxygenase-1 and -2 activity and protein levels in human skeletal muscle.

    Science.gov (United States)

    Carroll, Chad C; O'Connor, Devin T; Steinmeyer, Robert; Del Mundo, Jonathon D; McMullan, David R; Whitt, Jamie A; Ramos, Jahir E; Gonzales, Rayna J

    2013-07-01

    This study evaluated the activity and content of cyclooxygenase (COX)-1 and -2 in response to acute resistance exercise (RE) in human skeletal muscle. Previous work suggests that COX-1, but not COX-2, is the primary COX isoform elevated with resistance exercise in human skeletal muscle. COX activity, however, has not been assessed after resistance exercise in humans. It was hypothesized that RE would increase COX-1 but not COX-2 activity. Muscle biopsies were taken from the vastus lateralis of nine young men (25 ± 1 yr) at baseline (preexercise), 4, and 24 h after a single bout of knee extensor RE (three sets of 10 repetitions at 70% of maximum). Tissue lysate was assayed for COX-1 and COX-2 activity. COX-1 and COX-2 protein levels were measured via Western blot analysis. COX-1 activity increased at 4 h (P 0.05) with acute RE. In contrast, COX-2 protein levels were nearly 3-fold greater (P > 0.05) at 4 h and 5-fold greater (P = 0.06) at 24 h, compared with preexercise. In conclusion, COX-1 activity increases transiently with exercise independent of COX-1 protein levels. In contrast, both COX-2 activity and protein levels were elevated with exercise, and this elevation persisted to at least 24 h after RE.

  19. Cloning and characterization of a G protein-activated human phosphoinositide-3 kinase.

    Science.gov (United States)

    Stoyanov, B; Volinia, S; Hanck, T; Rubio, I; Loubtchenkov, M; Malek, D; Stoyanova, S; Vanhaesebroeck, B; Dhand, R; Nürnberg, B

    1995-08-04

    Phosphoinositide-3 kinase activity is implicated in diverse cellular responses triggered by mammalian cell surface receptors and in the regulation of protein sorting in yeast. Receptors with intrinsic and associated tyrosine kinase activity recruit heterodimeric phosphoinositide-3 kinases that consist of p110 catalytic subunits and p85 adaptor molecules containing Src homology 2 (SH2) domains. A phosphoinositide-3 kinase isotype, p110 gamma, was cloned and characterized. The p110 gamma enzyme was activated in vitro by both the alpha and beta gamma subunits of heterotrimeric guanosine triphosphate (GTP)-binding proteins (G proteins) and did not interact with p85. A potential pleckstrin homology domain is located near its amino terminus. The p110 gamma isotype may link signaling through G protein-coupled receptors to the generation of phosphoinositide second messengers phosphorylated in the D-3 position.

  20. Viral RNA annealing activities of human immunodeficiency virus type 1 nucleocapsid protein require only peptide domains outside the zinc fingers.

    Science.gov (United States)

    De Rocquigny, H; Gabus, C; Vincent, A; Fournié-Zaluski, M C; Roques, B; Darlix, J L

    1992-07-15

    The nucleocapsid (NC) of human immunodeficiency virus type 1 consists of a large number of NC protein molecules, probably wrapping the dimeric RNA genome within the virion inner core. NC protein is a gag-encoded product that contains two zinc fingers flanked by basic residues. In human immunodeficiency virus type 1 virions, NCp15 is ultimately processed into NCp7 and p6 proteins. During virion assembly the retroviral NC protein is necessary for core formation and genomic RNA encapsidation, which are essential for virus infectivity. In vitro NCp15 activates viral RNA dimerization, a process most probably linked in vivo to genomic RNA packaging, and replication primer tRNA(Lys,3) annealing to the initiation site of reverse transcription. To characterize the domains of human immunodeficiency virus type 1 NC protein necessary for its various functions, the 72-amino acid NCp7 and several derived peptides were synthesized in a pure form. We show here that synthetic NCp7 with or without the two zinc fingers has the RNA annealing activities of NCp15. Further deletions of the N-terminal 12 and C-terminal 8 amino acids, leading to a 27-residue peptide lacking the finger domains, have little or no effect on NC protein activity in vitro. However deletion of short sequences containing basic residues flanking the first finger leads to a complete loss of NC protein activity. It is proposed that the basic residues and the zinc fingers cooperate to select and package the genomic RNA in vivo. Inhibition of the viral RNA binding and annealing activities associated with the basic residues flanking the first zinc finger of NC protein could therefore be used as a model for the design of antiviral agents.

  1. Structure of Human Tyrosinase Related Protein 1 Reveals a Binuclear Zinc Active Site Important for Melanogenesis

    NARCIS (Netherlands)

    Lai, Xuelei; Wichers, Harry J.; Soler-Lopez, Montserrat; Dijkstra, Bauke W.

    2017-01-01

    Tyrosinase-related protein 1 (TYRP1) is one of three tyrosinase-like glycoenzymes in human melanocytes that are key to the production of melanin, the compound responsible for the pigmentation of skin, eye, and hair. Difficulties with producing these enzymes in pure form have hampered the

  2. Cytotoxic activity of proteins isolated from extracts of Corydalis cava tubers in human cervical carcinoma HeLa cells

    Directory of Open Access Journals (Sweden)

    Balcerkiewicz Stanislaw

    2010-12-01

    Full Text Available Abstract Background Corydalis cava Schweigg. & Koerte, the plant of numerous pharmacological activities, together with the studied earlier by our group Chelidonium majus L. (Greater Celandine, belong to the family Papaveraceae. The plant grows in Central and South Europe and produces the sizeable subterraneous tubers, empty inside, which are extremely resistant to various pathogen attacks. The Corydalis sp. tubers are a rich source of many biologically active substances, with the extensive use in European and Asian folk medicine. They have analgetic, sedating, narcotic, anti-inflammatory, anti-allergic and anti-tumour activities. On the other hand, there is no information about possible biological activities of proteins contained in Corydalis cava tubers. Methods Nucleolytic proteins were isolated from the tubers of C. cava by separation on a heparin column and tested for DNase activity. Protein fractions showing nucleolytic activity were tested for cytotoxic activity in human cervical carcinoma HeLa cells. Cultures of HeLa cells were conducted in the presence of three protein concentrations: 42, 83 and 167 ng/ml during 48 h. Viability of cell cultures was appraised using XTT colorimetric test. Protein fractions were separated and protein bands were excised and sent for identification by mass spectrometry (LC-ESI-MS/MS. Results The studied protein fractions showed an inhibiting effect on mitochondrial activity of HeLa cells, depending on the administered dose of proteins. The most pronounced effect was obtained with the highest concentration of the protein (167 ng/ml - 43.45 ± 3% mitochondrial activity of HeLa cells were inhibited. Mass spectrometry results for the proteins of applied fractions showed that they contained plant defense- and pathogenesis-related (PR proteins. Conclusions The cytotoxic effect of studied proteins toward HeLa cell line cells has been evident and dependent on increasing dose of the protein. The present study, most

  3. Discovery of Cryoprotective Activity in Human Genome-Derived Intrinsically Disordered Proteins

    Directory of Open Access Journals (Sweden)

    Naoki Matsuo

    2018-01-01

    Full Text Available Intrinsically disordered proteins (IDPs are an emerging phenomenon. They may have a high degree of flexibility in their polypeptide chains, which lack a stable 3D structure. Although several biological functions of IDPs have been proposed, their general function is not known. The only finding related to their function is the genetically conserved YSK2 motif present in plant dehydrins. These proteins were shown to be IDPs with the YSK2 motif serving as a core region for the dehydrins’ cryoprotective activity. Here we examined the cryoprotective activity of randomly selected IDPs toward the model enzyme lactate dehydrogenase (LDH. All five IDPs that were examined were in the range of 35–45 amino acid residues in length and were equally potent at a concentration of 50 μg/mL, whereas folded proteins, the PSD-95/Dlg/ZO-1 (PDZ domain, and lysozymes had no potency. We further examined their cryoprotective activity toward glutathione S-transferase as an example of the other enzyme, and toward enhanced green fluorescent protein as a non-enzyme protein example. We further examined the lyophilization protective activity of the peptides toward LDH, which revealed that some IDPs showed a higher activity than that of bovine serum albumin (BSA. Based on these observations, we propose that cryoprotection is a general feature of IDPs. Our findings may become a clue to various industrial applications of IDPs in the future.

  4. The antibacterial activity of peptides derived from human beta-2 glycoprotein I is inhibited by protein H and M1 protein from Streptococcus pyogenes

    NARCIS (Netherlands)

    Nilsson, Maria; Wasylik, Sylwia; Mörgelin, Matthias; Olin, Anders I.; Meijers, Joost C. M.; Derksen, Ronald H. W. M.; de Groot, Philip G.; Herwald, Heiko

    2008-01-01

    During the last years, the importance of antibacterial peptides has attracted considerable attention. We report here that peptides derived from the fifth domain of beta-2 glycoprotein I (beta(2)GPI), a human heparin binding plasma protein, have antibacterial activities against Gram-positive and

  5. TRIM45, a novel human RBCC/TRIM protein, inhibits transcriptional activities of ElK-1 and AP-1

    International Nuclear Information System (INIS)

    Wang Yuequn; Li Yongqing; Qi Xinzhu; Yuan Wuzhou; Ai Jianping; Zhu Chuanbing; Cao Lei; Yang Hong; Liu Fang; Wu Xiushan; Liu Mingyao

    2004-01-01

    The tripartite motif (TRIM) proteins play important roles in a variety of cellular functions including cell proliferation, differentiation, development, oncogenesis, and apoptosis. In this study, we report the identification and characterization of the human tripartite motif-containing protein 45 (TRIM45), a novel member of the TRIM family, from a human embryonic heart cDNA library. TRIM45 has a predicted 580 amino acid open reading frame, encoding a putative 64-kDa protein. The N-terminal region harbors a RING finger, two B-boxes, and a predicted α-helical coiled-coil domain, which together form the RBCC/TRIM motif found in a large family of proteins, whereas the C-terminal region contains a filamin-type immunoglobulin (IG-FLMN) domain. Northern blot analysis indicates that TRIM45 is expressed in a variety of human adult and embryonic tissues. In the cell, TRIM45 protein is expressed both in cytoplasm and in cell nucleus. Overexpression of TRIM45 in COS-7 cells inhibits the transcriptional activities of ElK-1 and AP-1. These results suggest that TRIM45 may act as a new transcriptional repressor in mitogen-activated protein kinase signaling pathway

  6. Protein secretion in human mammary epithelial cells following HER1 receptor activation: influence of HER2 and HER3 expression

    International Nuclear Information System (INIS)

    Zhang, Yi; Gonzalez, Rachel M; Zangar, Richard C

    2011-01-01

    Protein secretion by mammary cells results in autocrine and paracrine signaling that defines cell growth, migration and the extracellular environment. Even so, we have a limited understanding of the cellular processes that regulate protein secretion. In this study, we utilize human epithelial mammary cell (HMEC) lines that were engineered to express different levels of HER1, HER2 and HER3. Using an ELISA microarray platform, we evaluate the effects of epidermal growth factor family receptor (HER) expression on protein secretion in the HMEC lines upon initiation of HER1 receptor activation. The secreted proteins include three HER1 ligands, interleukins 1α and 18, RANTES, vascular-endothelial and platelet-derived growth factors, matrix metalloproteases 1, 2 and 9, and the extracellular portion of the HER1 and HER2 proteins. In addition, we investigate whether MAPK/Erk and PI3K/Akt signaling regulate protein secretion in these cell lines and if so, whether the involvement of HER2 or HER3 receptor alters their response to MAPK/Erk and PI3K/Akt signal pathway inhibition in terms of protein secretion. Differential expression of HER2 and HER3 receptors alters the secretion of a variety of growth factors, cytokines, and proteases. Some alterations in protein secretion are still observed when MAPK/Erk or PI3K/Akt signaling is inhibited. This study suggests that HER overexpression orchestrates broad changes in the tumor microenvironment by altering the secretion of a diverse variety of biologically active proteins

  7. Prostaglandins with antiproliferative activity induce the synthesis of a heat shock protein in human cells

    International Nuclear Information System (INIS)

    Santoro, M.G.; Garaci, E.; Amici, C.

    1989-01-01

    Prostaglandins (PGs)A 1 and J 2 were found to potently suppress the proliferation of human K562 erythroleukemia cells and to induce the synthesis of a 74-kDa protein (p74) that was identified as a heat shock protein related to the major 70-kDa heat shock protein group. p74 synthesis was stimulated at doses of PGA 1 and PGJ 2 that inhibited cell replication, and its accumulation ceased upon removal of the PG-induced proliferation block. PGs that did not affect K562 cell replication did not induce p74 synthesis. p74 was found to be localized mainly in the cytoplasm of PG-treated cells, but moderate amounts were found also in dense areas of the nucleus after PGJ 2 treatment. p74 was not necessarily associated with cytotoxicity or with inhibition of cell protein synthesis. The results described support the hypothesis that synthesis of the 70-kDa heat shock proteins is associated with changes in cell proliferation. The observation that PGs can induce the synthesis of heat shock proteins expands our understanding of the mechanism of action of these compounds whose regulatory role is well known in many physiological phenomena, including the control of fever production

  8. The identification and characterization of nucleic acid chaperone activity of human enterovirus 71 nonstructural protein 3AB.

    Science.gov (United States)

    Tang, Fenfen; Xia, Hongjie; Wang, Peipei; Yang, Jie; Zhao, Tianyong; Zhang, Qi; Hu, Yuanyang; Zhou, Xi

    2014-09-01

    Human enterovirus 71 (EV71) belongs to the genus Enterovirus in the family Picornaviridae and has been recognized as one of the most important pathogens that cause emerging infectious disease. Despite of the importance of EV71, the nonstructural protein 3AB from this virus is little understood for its function during EV71 replication. Here we expressed EV71 3AB protein as recombinant protein in a eukaryotic expression system and uncovered that this protein possesses a nucleic acid helix-destabilizing and strand annealing acceleration activity in a dose-dependent manner, indicating that EV71 3AB is a nucleic acid chaperone protein. Moreover, we characterized the RNA chaperone activity of EV71 3AB, and revealed that divalent metal ions, such as Mg(2+) and Zn(2+), were able to inhibit the RNA helix-destabilizing activity of 3AB to different extents. Moreover, we determined that 3B plus the last 7 amino acids at the C-terminal of 3A (termed 3B+7) possess the RNA chaperone activity, and five amino acids, i.e. Lys-80, Phe-82, Phe-85, Tyr-89, and Arg-103, are critical and probably the active sites of 3AB for its RNA chaperone activity. This report reveals that EV71 3AB displays an RNA chaperone activity, adds a new member to the growing list of virus-encoded RNA chaperones, and provides novel knowledge about the virology of EV71. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Ursodeoxycholic acid reduces protein levels and nucleation-promoting activity in human gallbladder bile

    NARCIS (Netherlands)

    van Erpecum, K. J.; Portincasa, P.; Eckhardt, E.; Go, P. M.; vanBerge-Henegouwen, G. P.; Groen, A. K.

    1996-01-01

    Background & Aims: Ursodeoxycholic acid prevents gallstone formation in selected patients. The aim of this study was to examine whether decreased concentration and nucleation-promoting activity of various proteins contribute to this beneficial effect. Methods: Gallbladder bile of 13 patients with

  10. Nucleotide sequence of cloned cDNA for human sphingolipid activator protein 1 precursor

    International Nuclear Information System (INIS)

    Dewji, N.N.; Wenger, D.A.; O'Brien, J.S.

    1987-01-01

    Two cDNA clones encoding prepro-sphingolipid activator protein 1 (SAP-1) were isolated from a λ gt11 human hepatoma expression library using polyclonal antibodies. These had inserts of ≅ 2 kilobases (λ-S-1.2 and λ-S-1.3) and both were both homologous with a previously isolated clone (λ-S-1.1) for mature SAP-1. The authors report here the nucleotide sequence of the longer two EcoRI fragments of S-1.2 and S-1.3 that were not the same and the derived amino acid sequences of mature SAP-1 and its prepro form. The open reading frame encodes 19 amino acids, which are colinear with the amino-terminal sequence of mature SAP-1, and extends far beyond the predicted carboxyl terminus of mature SAP-1, indicating extensive carboxyl-terminal processing. The nucleotide sequence of cDNA encoding prepro-SAP-1 includes 1449 bases from the assigned initiation codon ATG at base-pair 472 to the stop codon TGA at base-pair 1921. The first 23 amino acids coded after the initiation ATG are characteristic of a signal peptide. The calculated molecular mass for a polypeptide encoded by 1449 bases is ≅ 53 kDa, in keeping with the reported value for pro-SAP-1. The data indicate that after removal of the signal peptide mature SAP-1 is generated by removing an additional 7 amino acids from the amino terminus and ≅ 373 amino acids from the carboxyl terminus. One potential glycosylation site was previously found in mature SAP-1. Three additional potential glycosylation sites are present in the processed carboxyl-terminal polypeptide, which they designate as P-2

  11. Insight into temperature dependence of GTPase activity in human guanylate binding protein-1.

    Directory of Open Access Journals (Sweden)

    Anjana Rani

    Full Text Available Interferon-γ induced human guanylate binding protein-1(hGBP1 belongs to a family of dynamin related large GTPases. Unlike all other GTPases, hGBP1 hydrolyzes GTP to a mixture of GDP and GMP with GMP being the major product at 37°C but GDP became significant when the hydrolysis reaction was carried out at 15°C. The hydrolysis reaction in hGBP1 is believed to involve with a number of catalytic steps. To investigate the effect of temperature in the product formation and on the different catalytic complexes of hGBP1, we carried out temperature dependent GTPase assays, mutational analysis, chemical and thermal denaturation studies. The Arrhenius plot for both GDP and GMP interestingly showed nonlinear behaviour, suggesting that the product formation from the GTP-bound enzyme complex is associated with at least more than one step. The negative activation energy for GDP formation and GTPase assay with external GDP together indicate that GDP formation occurs through the reversible dissociation of GDP-bound enzyme dimer to monomer, which further reversibly dissociates to give the product. Denaturation studies of different catalytic complexes show that unlike other complexes the free energy of GDP-bound hGBP1 decreases significantly at lower temperature. GDP formation is found to be dependent on the free energy of the GDP-bound enzyme complex. The decrease in the free energy of this complex at low temperature compared to at high is the reason for higher GDP formation at low temperature. Thermal denaturation studies also suggest that the difference in the free energy of the GTP-bound enzyme dimer compared to its monomer plays a crucial role in the product formation; higher stability favours GMP but lower favours GDP. Thus, this study provides the first thermodynamic insight into the effect of temperature in the product formation of hGBP1.

  12. Calpain activation by ROS mediates human ether-a-go-go-related gene protein degradation by intermittent hypoxia.

    Science.gov (United States)

    Wang, N; Kang, H S; Ahmmed, G; Khan, S A; Makarenko, V V; Prabhakar, N R; Nanduri, J

    2016-03-01

    Human ether-a-go-go-related gene (hERG) channels conduct delayed rectifier K(+) current. However, little information is available on physiological situations affecting hERG channel protein and function. In the present study we examined the effects of intermittent hypoxia (IH), which is a hallmark manifestation of sleep apnea, on hERG channel protein and function. Experiments were performed on SH-SY5Y neuroblastoma cells, which express hERG protein. Cells were exposed to IH consisting of alternating cycles of 30 s of hypoxia (1.5% O2) and 5 min of 20% O2. IH decreased hERG protein expression in a stimulus-dependent manner. A similar reduction in hERG protein was also seen in adrenal medullary chromaffin cells from IH-exposed neonatal rats. The decreased hERG protein was associated with attenuated hERG K(+) current. IH-evoked hERG protein degradation was not due to reduced transcription or increased proteosome/lysomal degradation. Rather it was mediated by calcium-activated calpain proteases. Both COOH- and NH2-terminal sequences of the hERG protein were the targets of calpain-dependent degradation. IH increased reactive oxygen species (ROS) levels, intracellular Ca(2+) concentration ([Ca(2+)]i), calpain enzyme activity, and hERG protein degradation, and all these effects were prevented by manganese-(111)-tetrakis-(1-methyl-4-pyridyl)-porphyrin pentachloride, a membrane-permeable ROS scavenger. These results demonstrate that activation of calpains by ROS-dependent elevation of [Ca(2+)]i mediates hERG protein degradation by IH. Copyright © 2016 the American Physiological Society.

  13. Characterization of human endothelial cell urokinase-type plasminogen activator receptor protein and messenger RNA

    DEFF Research Database (Denmark)

    Barnathan, E S; Kuo, A; Karikó, K

    1990-01-01

    Human umbilical vein endothelial cells in culture (HUVEC) express receptors for urokinase-type plasminogen activators (u-PA). The immunochemical nature of this receptor and its relationship to u-PA receptors expressed by other cell types is unknown. Cross-linking active site-blocked u-PA to HUVEC...... an endothelial cell cDNA library using the polymerase chain reaction (PCR) and oligonucleotide primers corresponding to the DNA sequence of the receptor cloned from transformed human fibroblasts (Roldan et al, EMBO J 9:467, 1990). The size of the cDNA (approximately 1,054 base pairs, bp) and the presence...

  14. In vitro activation of transcription by the human T-cell leukemia virus type I Tax protein.

    Science.gov (United States)

    Matthews, M A; Markowitz, R B; Dynan, W S

    1992-05-01

    The human T-cell leukemia virus type I (HTLV-I) regulatory protein Tax activates transcription of the proviral long terminal repeats and a number of cellular promoters. We have developed an in vitro system to characterize the mechanism by which Tax interacts with the host cell transcription machinery. Tax was purified from cells infected with a baculovirus expression vector. Addition of these Tax preparations to nuclear extracts from uninfected human T lymphocytes activated transcription of the HTLV-I long terminal repeat approximately 10-fold. Transcription-stimulatory activity copurified with the immunoreactive 40-kDa Tax polypeptide on gel filtration chromatography, and, as expected, the effect of recombinant Tax was diminished in HTLV-I-infected T-lymphocyte extracts containing endogenous Tax. Tax-mediated transactivation in vivo has been previously shown to require 21-bp-repeat Tax-responsive elements (TxREs) in the promoter DNA. Stimulation of transcription in vitro was also strongly dependent on these sequences. To investigate the mechanism of Tax transactivation, cellular proteins that bind the 21-bp-repeat TxREs were prepared by DNA affinity chromatography. Recombinant Tax markedly increased the formation of a specific host protein-DNA complex detected in an electrophoretic mobility shift assay. These data suggest that Tax activates transcription through a direct interaction with cellular proteins that bind to the 21-bp-repeat TxREs.

  15. p38 mitogen-activated protein kinase mediates IL-8 induction by the ribotoxin deoxynivalenol in human monocytes

    International Nuclear Information System (INIS)

    Islam, Zahidul; Gray, Jennifer S.; Pestka, James J.

    2006-01-01

    The effects of the ribotoxic trichothecene deoxynivalenol (DON) on mitogen-activated protein kinase (MAPK)-mediated IL-8 expression were investigated in cloned human monocytes and peripheral blood mononuclear cells (PBMC). DON (250 to 1000 ng/ml) induced both IL-8 mRNA and IL-8 heteronuclear RNA (hnRNA), an indicator of IL-8 transcription, in the human U937 monocytic cell line in a concentration-dependent manner. Expression of IL-8 hnRNA, mRNA and protein correlated with p38 phosphorylation and was completely abrogated by the p38 MAPK inhibitor SB203580. DON at 500 ng/ml similarly induced p38-dependent IL-8 protein and mRNA expression in PBMC cultures from healthy volunteers. Significantly increased IL-6 and IL-1β intracellular protein and mRNA expression was also observed in PBMC treated with DON (500 ng/ml) which were also partially p38-dependent. Flow cytometry of PBMC revealed that DON-induced p38 phosphorylation varied among individuals relative to both threshold toxin concentrations (25-100 ng/ml) and relative increases in percentages of phospho-p38 + cells. DON-induced p38 activation occurred exclusively in the CD14 + monocyte population. DON was devoid of agonist activity for human Toll-like receptors 2, 3, 4, 5, 7, 8 and 9. However, two other ribotoxins, emetine and anisomycin, induced p38 phosphorylation in PBMC similarly to DON. Taken together, these data suggest that (1) p38 activation was required for induction of IL-8 and proinflammatory gene expression in the monocyte and (2) DON induced p38 activation in human monocytes via the ribotoxic stress response

  16. Structural studies of human Naked2: A biologically active intrinsically unstructured protein

    International Nuclear Information System (INIS)

    Hu Tianhui; Krezel, Andrzej M.; Li Cunxi; Coffey, Robert J.

    2006-01-01

    Naked1 and 2 are two mammalian orthologs of Naked Cuticle, a canonical Wnt signaling antagonist in Drosophila. Naked2, but not Naked1, interacts with transforming growth factor-α (TGFα) and escorts TGFα-containing vesicles to the basolateral membrane of polarized epithelial cells. Full-length Naked2 is poorly soluble. Since most functional domains, including the Dishevelled binding region, EF-hand, vesicle recognition, and membrane targeting motifs, reside in the N-terminal half of the protein, we expressed and purified the first 217 residues of human Naked2 and performed a functional analysis of this fragment. Its circular dichroism (CD) and nuclear magnetic resonance (NMR) spectra showed no evidence of secondary and/or tertiary structure. The fragment did not bind calcium or zinc. These results indicate that the N-terminal half of Naked2 behaves as an intrinsically unstructured protein

  17. Activation of p44/42 in Human Natural Killer Cells Decreases Cell-surface Protein Expression: Relationship to Tributyltin-induced alterations of protein expression

    Science.gov (United States)

    Dudimah, Fred D.; Abraha, Abraham; Wang, Xiaofei; Whalen, Margaret M.

    2010-01-01

    Tributyltin (TBT) activates the mitogen activated protein kinase (MAPK), p44/42 in human natural killer (NK) cells. TBT also reduces NK cytotoxic function and decreases the expression of several NK-cell proteins. To understand the role that p44/42 activation plays in TBT-induced loss of NK cell function, we have investigated how selective activation of p44/42 by phorbol 12-myristate 13-acetate (PMA) affects NK cells. Previously we showed that PMA caused losses of lytic function similar to those seen with TBT exposures. Here we examined activation of p44/42 in the regulation of NK-cell protein expression and how this regulation may explain the protein expression changes seen with TBT exposures. NK cells exposed to PMA were examined for levels of cell-surface proteins, granzyme mRNA, and perforin mRNA expression. The expression of CD11a, CD16, CD18, and CD56 were reduced, perforin mRNA levels were unchanged and granzyme mRNA levels were increased. To verify that activation of p44/42 was responsible for the alterations seen in CD11a, CD16, CD18, and CD56 with PMA, NK cells were treated with the p44/42 pathway inhibitor (PD98059) prior to PMA exposures. In the presence of PD98059, PMA caused no decreases in the expression of the cell-surface proteins. Results of these studies indicate that the activation of p44/42 may lead to the loss of NK cell cytotoxic function by decreasing the expression of CD11a, CD16, CD18, and CD56. Further, activation of p44/42 appears to be at least in part responsible for the TBT-induced decreases in expression of CD16, CD18, and CD56. PMID:20883105

  18. 5'AMP activated protein kinase expression in human skeletal muscle: effects of strength training and type 2 diabetes

    DEFF Research Database (Denmark)

    Wojtaszewski, Jørgen; Birk, Jesper Bratz; Frøsig, Christian

    2005-01-01

    adaptations within the AMPK system itself. We investigated the effect of strength training and T2DM on the isoform expression and the heterotrimeric composition of the AMPK in human skeletal muscle. Ten patients with T2DM and seven healthy subjects strength trained (T) one leg for 6 weeks, while the other leg......Strength training enhances insulin sensitivity and represents an alternative to endurance training for patients with type 2 diabetes (T2DM). The 5'AMP-activated protein kinase (AMPK) may mediate adaptations in skeletal muscle in response to exercise training; however, little is known about...... remained untrained (UT). Muscle biopsies were obtained before and after the training period. Basal AMPK activity and protein/mRNA expression of both catalytic (alpha1 and alpha2) and regulatory (beta1, beta2, gamma1, gamma2a, gamma2b and gamma3) AMPK isoforms were independent of T2DM, whereas the protein...

  19. Functional Dynamics within the Human Ribosome Regulate the Rate of Active Protein Synthesis.

    Science.gov (United States)

    Ferguson, Angelica; Wang, Leyi; Altman, Roger B; Terry, Daniel S; Juette, Manuel F; Burnett, Benjamin J; Alejo, Jose L; Dass, Randall A; Parks, Matthew M; Vincent, C Theresa; Blanchard, Scott C

    2015-11-05

    The regulation of protein synthesis contributes to gene expression in both normal physiology and disease, yet kinetic investigations of the human translation mechanism are currently lacking. Using single-molecule fluorescence imaging methods, we have quantified the nature and timing of structural processes in human ribosomes during single-turnover and processive translation reactions. These measurements reveal that functional complexes exhibit dynamic behaviors and thermodynamic stabilities distinct from those observed for bacterial systems. Structurally defined sub-states of pre- and post-translocation complexes were sensitive to specific inhibitors of the eukaryotic ribosome, demonstrating the utility of this platform to probe drug mechanism. The application of three-color single-molecule fluorescence resonance energy transfer (smFRET) methods further revealed a long-distance allosteric coupling between distal tRNA binding sites within ribosomes bearing three tRNAs, which contributed to the rate of processive translation. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Effects of Butyltins (BTs) on Mitogen-Activated-Protein Kinase Kinase Kinase (MAP3K) and Ras Activity in Human Natural Killer Cells

    Science.gov (United States)

    Celada, Lindsay J.; Whalen, Margaret M.

    2013-01-01

    Butyltins (BTs) contaminate the environment and are found in human blood. BTs, tributyltin (TBT) and dibutyltin (DBT), diminish the cytotoxic function and levels of key proteins of human natural killer (NK) cells. NK cells are an initial immune defense against tumors, virally-infected cells and antibody-coated cells and thus critical to human health. The signaling pathways that regulate NK cell functions include mitogen-activated protein kinases (MAPKs). Studies have shown that exposure to BTs leads to the activation of specific MAPKs and MAPK kinases (MAP2Ks) in human NK cells. MAP2K kinases (MAP3Ks) are upstream activators of MAP2Ks, which then activate MAPKs. The current study examined if BT-induced activation of MAP3Ks was responsible for MAP2K and thus, MAPK activation. This study examines the effects of TBT and DBT on the total levels of two MAP3Ks, c-Raf and ASK1, as well as activating and inhibitory phosphorylation sites on these MAP3Ks. In addition, the immediate upstream activator of c-Raf, Ras, was examined for BT-induced alterations. Our results show significant activation of the MAP3K, c-Raf, in human NK cells within 10 minutes of TBT exposure and the MAP3K, ASK1, after one hour exposures to TBT. In addition, our results suggest that both TBT and DBT are impacting the regulation of c-Raf. PMID:24038145

  1. Activation of Protein Kinase C and Protein Kinase D in Human Natural Killer Cells: Effects of Tributyltin, Dibutyltin, and Tetrabromobisphenol A

    Science.gov (United States)

    Rana, Krupa; Whalen, Margaret M.

    2015-01-01

    Up to now, the ability of target cells to activate protein kinase C (PKC) and protein kinase D (PKD) (which is often a downstream target of PKC) has not been examined in natural killer (NK) lymphocytes. Here we examined whether exposure of human NK cells to lysis sensitive tumor cells activated PKC and PKD. The results of these studies show for the first time that activation of PKC and PKD occurs in response to target cell binding to NK cells. Exposure of NK cells to K562 tumor cells for 10 and 30 minutes increased phosphorylation/activation of both PKC and PKD by roughly 2 fold. Butyltins (tributyltin (TBT); dibutyltin (DBT)) and brominated compounds (tetrabromobisphenol A (TBBPA)) are environmental contaminants that are found in human blood. Exposures of NK cells to TBT, DBT or TBBPA decrease NK cell lytic function in part by activating the mitogen activated protein kinases (MAPKs) that are part of the NK lytic pathway. We established that PKC and PKD are part of the lytic pathway upstream of MAPKs and thus we investigated whether DBT, TBT, and TBBPA exposures activated PKC and PKD. TBT activated PKC by 2–3 fold at 10 min at concentrations ranging from 50–300 nM while DBT caused a 1.3 fold activation at 2.5 μM at 10 min. Both TBT and DBT caused an approximately 2 fold increase in phosphorylation/activation of PKC. Exposures to TBBPA caused no statistically significant changes in either PKC or PKD activation. PMID:26228090

  2. Overexpression of SERBP1 (Plasminogen activator inhibitor 1 RNA binding protein) in human breast cancer is correlated with favourable prognosis

    International Nuclear Information System (INIS)

    Serce, Nuran Bektas; Knuechel, Ruth; Beckmann, Matthias W; Fasching, Peter A; Dahl, Edgar; Boesl, Andreas; Klaman, Irina; Serényi, Sonja von; Noetzel, Erik; Press, Michael F; Dimmler, Arno; Hartmann, Arndt; Sehouli, Jalid

    2012-01-01

    Plasminogen activator inhibitor 1 (PAI-1) overexpression is an important prognostic and predictive biomarker in human breast cancer. SERBP1, a protein that is supposed to regulate the stability of PAI-1 mRNA, may play a role in gynaecological cancers as well, since upregulation of SERBP1 was described in ovarian cancer recently. This is the first study to present a systematic characterisation of SERBP1 expression in human breast cancer and normal breast tissue at both the mRNA and the protein level. Using semiquantitative realtime PCR we analysed SERBP1 expression in different normal human tissues (n = 25), and in matched pairs of normal (n = 7) and cancerous breast tissues (n = 7). SERBP1 protein expression was analysed in two independent cohorts on tissue microarrays (TMAs), an initial evaluation set, consisting of 193 breast carcinomas and 48 normal breast tissues, and a second large validation set, consisting of 605 breast carcinomas. In addition, a collection of benign (n = 2) and malignant (n = 6) mammary cell lines as well as breast carcinoma lysates (n = 16) were investigated for SERBP1 expression by Western blot analysis. Furthermore, applying non-radioisotopic in situ hybridisation a subset of normal (n = 10) and cancerous (n = 10) breast tissue specimens from the initial TMA were analysed for SERBP1 mRNA expression. SERBP1 is not differentially expressed in breast carcinoma compared to normal breast tissue, both at the RNA and protein level. However, recurrence-free survival analysis showed a significant correlation (P = 0.008) between abundant SERBP1 expression in breast carcinoma and favourable prognosis. Interestingly, overall survival analysis also displayed a tendency (P = 0.09) towards favourable prognosis when SERBP1 was overexpressed in breast cancer. The RNA-binding protein SERBP1 is abundantly expressed in human breast cancer and may represent a novel breast tumour marker with prognostic significance. Its potential involvement in the

  3. Effects of oxaliplatin and oleic acid Gc-protein-derived macrophage-activating factor on murine and human microglia.

    Science.gov (United States)

    Branca, Jacopo J V; Morucci, Gabriele; Malentacchi, Francesca; Gelmini, Stefania; Ruggiero, Marco; Pacini, Stefania

    2015-09-01

    The biological properties and characteristics of microglia in rodents have been widely described, but little is known about these features in human microglia. Several murine microglial cell lines are used to investigate neurodegenerative and neuroinflammatory conditions; however, the extrapolation of the results to human conditions is frequently met with criticism because of the possibility of species-specific differences. This study compares the effects of oxaliplatin and of oleic acid Gc-protein-derived macrophage-activating factor (OA-GcMAF) on two microglial cell lines, murine BV-2 cells and human C13NJ cells. Cell viability, cAMP levels, microglial activation, and vascular endothelial growth factor (VEGF) expression were evaluated. Our data demonstrate that oxaliplatin induced a significant decrease in cell viability in BV-2 and in C13NJ cells and that this effect was not reversed with OA-GcMAF treatment. The signal transduction pathway involving cAMP/VEGF was activated after treatment with oxaliplatin and/or OA-GcMAF in both cell lines. OA-GcMAF induced a significant increase in microglia activation, as evidenced by the expression of the B7-2 protein, in BV-2 as well as in C13NJ cells that was not associated with a concomitant increase in cell number. Furthermore, the effects of oxaliplatin and OA-GcMAF on coculture morphology and apoptosis were evaluated. Oxaliplatin-induced cell damage and apoptosis were nearly completely reversed by OA-GcMAF treatment in both BV-2/SH-SY5Y and C13NJ/SH-SY5Y cocultures. Our data show that murine and human microglia share common signal transduction pathways and activation mechanisms, suggesting that the murine BV-2 cell line may represent an excellent model for studying human microglia. © 2015 Wiley Periodicals, Inc.

  4. The mitogenic activities of bean proteins determined by assay of the incorporation of sup(3)H - thymidine by human lymphocytes

    International Nuclear Information System (INIS)

    Derbyshire, E.; Carvalho, M.T.V.; Vitti, D.M.S.; Costa, C.P. da

    1988-01-01

    The proteins in a saline extract from cotyledons of the bean cultivar Goiano precoce included a protein with electrophoretic mobility equal to that of a commercial preparation of bean mitogen. The crude extract stimulated the incorporation of sup(3)H-tymidine by cultures of human lymphocytes at concentrations of extracted protein from 30 mu g - 300 mu g/culture, and the existence of an optimal concentration in the vicinity of 175 mu g/culture was indicated by the data. The range of active concentrations and the optimal concentration of the heterogeneous extract were 12-15 times greater than the corresponding values obtained when the commercial mitogen was employed. Microscopic examinations showed the presence of blast cells and mitotic figures only in cultures which included seed extract or commercial mitogen. (author)

  5. Human factor H-related protein 2 (CFHR2 regulates complement activation.

    Directory of Open Access Journals (Sweden)

    Hannes U Eberhardt

    Full Text Available Mutations and deletions within the human CFHR gene cluster on chromosome 1 are associated with diseases, such as dense deposit disease, CFHR nephropathy or age-related macular degeneration. Resulting mutant CFHR proteins can affect complement regulation. Here we identify human CFHR2 as a novel alternative pathway complement regulator that inhibits the C3 alternative pathway convertase and terminal pathway assembly. CFHR2 is composed of four short consensus repeat domains (SCRs. Two CFHR2 molecules form a dimer through their N-terminal SCRs, and each of the two C-terminal ends can bind C3b. C3b bound CFHR2 still allows C3 convertase formation but the CFHR2 bound convertases do not cleave the substrate C3. Interestingly CFHR2 hardly competes off factor H from C3b. Thus CFHR2 likely acts in concert with factor H, as CFHR2 inhibits convertases while simultaneously allowing factor H assisted degradation by factor I.

  6. Simian Immunodeficiency Virus and Human Immunodeficiency Virus Type 1 Nef Proteins Show Distinct Patterns and Mechanisms of Src Kinase Activation

    Science.gov (United States)

    Greenway, Alison L.; Dutartre, Hélène; Allen, Kelly; McPhee, Dale A.; Olive, Daniel; Collette, Yves

    1999-01-01

    The nef gene from human and simian immunodeficiency viruses (HIV and SIV) regulates cell function and viral replication, possibly through binding of the nef product to cellular proteins, including Src family tyrosine kinases. We show here that the Nef protein encoded by SIVmac239 interacts with and also activates the human Src kinases Lck and Hck. This is in direct contrast to the inhibitory effect of HIV type 1 (HIV-1) Nef on Lck catalytic activity. Unexpectedly, however, the interaction of SIV Nef with human Lck or Hck is not mediated via its consensus proline motif, which is known to mediate HIV-1 Nef binding to Src homology 3 (SH3) domains, and various experimental analyses failed to show significant interaction of SIV Nef with the SH3 domain of either kinase. Instead, SIV Nef can bind Lck and Hck SH2 domains, and its N-terminal 50 amino acid residues are sufficient for Src kinase binding and activation. Our results provide evidence for multiple mechanisms by which Nef binds to and regulates Src kinases. PMID:10364375

  7. The roles of MCP-1 and protein kinase C delta activation in human eosinophilic leukemia EoL-1 cells.

    Science.gov (United States)

    Lee, Ji-Sook; Yang, Eun Ju; Kim, In Sik

    2009-12-01

    Idiopathic hypereosinophilc syndrome is a disorder associated with clonally eosinophilic proliferation. The importance of FIP1-like-1-platelet-derived growth factor receptor-alpha (FIP1L1-PDGFRA) in the pathogenesis and classification of HES has been recently reported. In this study, we investigated the contribution of monocyte chemoattractant protein-1 (MCP-1)/CCL2 to chemotactic activity and protein kinase C delta (PKC delta in the human eosinophilic leukemia cell line EoL-1. These cells express CCR2 protein among the CC chemokine receptors (CCR1-5). MCP-1 induces strong migration of EoL-1 cells and the chemotaxis signal in response to MCP-1 involves a G(i)/G(o) protein, phospholipase C (PLC), PKC delta, p38 MAPK and NF-kappaB. MCP-1 activates p38 MAPK via G(i)/G(o) protein, PLC and PKC delta cascade. MCP-1 also induces NF-kappaB translocation and the activation is inhibited by PKC delta activation. The increase in the basal expression and activity of PKC delta in EoL-1 cells, compared to normal eosinophils, inhibits apoptosis in EoL-1 cells. Anti-apoptotic mechanism of PKC delta is related to inhibition of caspase 3 and caspase 9, but not to FIP1L1-PDGFRA. PKC delta functions as an anti-apoptotic molecule, and is involved in EoL-1 cell movement stimulated by MCP-1. This study contributes to an understanding of MCP-1 in eosinophil biology and pathogenic mechanism of eosinophilic disorders.

  8. Ubiquitin-Like Protein from Human Placental Extract Exhibits Collagenase Activity

    Science.gov (United States)

    De, Debashree; Datta Chakraborty, Piyali; Mitra, Jyotirmoy; Sharma, Kanika; Mandal, Somnath; Das, Aneesha; Chakrabarti, Saikat; Bhattacharyya, Debasish

    2013-01-01

    An aqueous extract of human placenta exhibits strong gelatinase/collagenase activity in zymography. 2-D gel electrophoresis of the extract with gelatin zymography in the second dimension displayed a single spot, identified as ubiquitin-like component upon MALDI/TOF MS/MS analysis. Immunoblot indicated presence of ubiquitin and absence of collagenase in the extract. Collagenase activity of the ubiquitin-like component was confirmed from the change in solubility of collagen in aqueous buffer, degradation of collagen by size-exclusion HPLC and atomic force microscopy. Quantification with DQ-gelatin showed that the extract contains 0.04 U/ml of collagenase activity that was inhibited up to 95% by ubiquitin antibody. Ubiquitin from bovine erythrocytes demonstrated mild collagenase activity. Bioinformatics studies suggest that placental ubiquitin and collagenase follow structurally divergent evolution. This thermostable intrinsic collagenase activity of placental extract might have wide physiological relevance in degrading and remodeling collagen as it is used as a drug for wound healing and pelvic inflammatory diseases. PMID:23555718

  9. Role of human recombinant activated protein C and low dose corticosteroid therapy in sepsis

    Directory of Open Access Journals (Sweden)

    Aparna Shukla

    2010-01-01

    Full Text Available Despite advances in modern medicine, sepsis remains a complex syndrome that has been associated with significant morbidity and mortality. Multiple organ failure associated with sepsis leads to high mortality and morbidity. About 28 - 50% deaths have been reported in patients with sepsis. The number of sepsis patients is increasing, with considerable burden on healthcare facilities. Various factors leading to a rise in the incidence of sepsis are (1 Improvement of diagnostic procedures (2 Increase in the number of immunocompromised patients taking treatment for various autoimmune disease, carcinomas, organ transplantation (3 Advances in intensive procedures (4 Nosocomial infections (5 Extensive use of antibiotics. With the better understanding of sepsis various modalities to modify pathophysiological response of septic patients have developed. Activated protein C and low-dose corticosteroid therapy have been tried in patients, with variable results.

  10. Innate Defense against Influenza A Virus: Activity of Human Neutrophil Defensins and Interactions of Defensins with Surfactant Protein D

    DEFF Research Database (Denmark)

    Hartshorn, Kevan L.; White, Mitchell R.; Tecle, Tesfaldet

    2006-01-01

    Surfactant protein D (SP-D) plays important roles in innate host defense against influenza A virus (IAV) infection, in part by modifying interactions with neutrophils. Human neutrophil defensins (HNPs) inhibit infectivity of enveloped viruses, including IAV. Our goal in this study was to characte......Surfactant protein D (SP-D) plays important roles in innate host defense against influenza A virus (IAV) infection, in part by modifying interactions with neutrophils. Human neutrophil defensins (HNPs) inhibit infectivity of enveloped viruses, including IAV. Our goal in this study...... was to characterize antiviral interactions between SP-D and HNPs. Recombinant and/or natural forms of SP-D and related collectins and HNPs were tested for antiviral activity against two different strains of IAV. HNPs 1 and 2 did not inhibit viral hemagglutination activity, but they interfered...... with the hemagglutination-inhibiting activity of SP-D. HNPs had significant viral neutralizing activity against divergent IAV strains. However, the HNPs generally had competitive effects when combined with SP-D in assays using an SP-D-sensitive IAV strain. In contrast, cooperative antiviral effects were noted in some...

  11. Human Salivary Protein Histatin 5 Has Potent Bactericidal Activity against ESKAPE Pathogens.

    Science.gov (United States)

    Du, Han; Puri, Sumant; McCall, Andrew; Norris, Hannah L; Russo, Thomas; Edgerton, Mira

    2017-01-01

    ESKAPE ( Enterococcus faecium , Staphylococcus aureus , Klebsiella pneumoniae , Acinetobacter baumanni , Pseudomonas aeruginosa , and Enterobacter species) pathogens have characteristic multiple-drug resistance and cause an increasing number of nosocomial infections worldwide. Peptide-based therapeutics to treat ESKAPE infections might be an alternative to conventional antibiotics. Histatin 5 (Hst 5) is a salivary cationic histidine-rich peptide produced only in humans and higher primates. It has high antifungal activity against Candida albicans through an energy-dependent, non-lytic process; but its bactericidal effects are less known. We found Hst 5 has bactericidal activity against S. aureus (60-70% killing) and A. baumannii (85-90% killing) in 10 and 100 mM sodium phosphate buffer (NaPB), while killing of >99% of P. aeruginosa , 60-80% E. cloacae and 20-60% of E. faecium was found in 10 mM NaPB. Hst 5 killed 60% of biofilm cells of P. aeruginosa , but had reduced activity against biofilms of S. aureus and A. baumannii . Hst 5 killed 20% of K. pneumonia biofilm cells but not planktonic cells. Binding and uptake studies using FITC-labeled Hst 5 showed E. faecium and E. cloacae killing required Hst 5 internalization and was energy dependent, while bactericidal activity was rapid against P. aeruginosa and A. baumannii suggesting membrane disruption. Hst 5-mediated killing of S. aureus was both non-lytic and energy independent. Additionally, we found that spermidine conjugated Hst 5 (Hst5-Spd) had improved killing activity against E. faecium, E. cloacae , and A. baumannii . Hst 5 or its derivative has antibacterial activity against five out of six ESKAPE pathogens and may be an alternative treatment for these infections.

  12. Influence of amino acids, dietary protein, and physical activity on muscle mass development in humans

    DEFF Research Database (Denmark)

    Dideriksen, Kasper; Reitelseder, Søren; Holm, Lars

    2013-01-01

    intake. Ingestion of excess protein exerts an unwanted load to the body and therefore, it is important to find the least amount of protein that provides the maximal hypertrophic stimulus. Hence, research has focused on revealing the relationship between protein intake (dose) and its resulting stimulation...... response dependent on the characteristics of the protein ingested. The effect of protein intake on muscle protein accretion can further be stimulated by prior exercise training. In the ageing population, physical training may counteract the development of "anabolic resistance" and restore the beneficial...

  13. Human Immunodeficiency Virus Tat-Activated Expression of Poliovirus Protein 2A Inhibits mRNA Translation

    Science.gov (United States)

    Sun, Xiao-Hong; Baltimore, David

    1989-04-01

    To study the effect of poliovirus protein 2A on cellular RNA translation, the tat control system of human immunodeficiency virus (HIV) was used. Protein 2A was expressed from a plasmid construct (pHIV/2A) incorporating the HIV long terminal repeat. Protein synthesis was measured by using chloramphenicol acetyltransferase as a reporter gene driven by the Rous sarcoma virus long terminal repeat. When HIV/2A was contransfected with the reporter, addition of a tat-producing plasmid caused at least a 50-fold drop in chloramphenicol acetyltransferase synthesis. A HeLa cell line carrying HIV/2A was established. In it, tat expression caused more than a 10-fold drop in chloramphenicol acetyltransferase synthesis from the reporter plasmid. Furthermore, 2A induction by tat caused cleavage of the cellular translation factor P220, a part of eukaryotic translation initiation factor 4F. Thus protein 2A can, by itself, carry out the inhibition of cellular protein synthesis characteristic of a poliovirus infection. Also, the HIV tat activation provides a very effective method to control gene expression in mammalian cells.

  14. The Human Papillomavirus Type 16 E6 Oncoprotein Activates mTORC1 Signaling and Increases Protein Synthesis ▿ †

    OpenAIRE

    Spangle, Jennifer M.; Münger, Karl

    2010-01-01

    The mammalian target of rapamycin (mTOR) kinase acts as a cellular rheostat that integrates signals from a variety of cellular signal transduction pathways that sense growth factor and nutrient availability as well as intracellular energy status. It was previously reported that the human papillomavirus type 16 (HPV16) E6 oncoprotein may activate the S6 protein kinase (S6K) through binding and E6AP-mediated degradation of the mTOR inhibitor tuberous sclerosis complex 2 (TSC2) (Z. Lu, X. Hu, Y....

  15. Combined roles of human IgG subclass, alternative complement pathway activation, and epitope density in the bactericidal activity of antibodies to meningococcal factor h binding protein.

    Science.gov (United States)

    Giuntini, Serena; Reason, Donald C; Granoff, Dan M

    2012-01-01

    Meningococcal vaccines containing factor H binding protein (fHbp) are in clinical development. fHbp binds human fH, which enables the meningococcus to resist complement-mediated bacteriolysis. Previously, we found that chimeric human IgG1 mouse anti-fHbp monoclonal antibodies (MAbs) had human complement-mediated bactericidal activity only if the MAb inhibited fH binding. Since IgG subclasses differ in their ability to activate complement, we investigated the role of human IgG subclasses on antibody functional activity. We constructed chimeric MAbs in which three different murine fHbp-specific binding domains were each paired with human IgG1, IgG2, or IgG3. Against a wild-type group B isolate, all three IgG3 MAbs, irrespective of their ability to inhibit fH binding, had bactericidal activity that was >5-fold higher than the respective IgG1 MAbs, while the IgG2 MAbs had the least activity. Against a mutant with increased fHbp expression, the anti-fHbp MAbs elicited greater C4b deposition (classical pathway) and greater bactericidal activity than against the wild-type strain, and the IgG1 MAbs had similar or greater activity than the respective IgG3 MAbs. The bactericidal activity against both wild-type and mutant strains also was dependent, in part, on activation of the alternative complement pathway. Thus, at lower epitope density in the wild-type strain, the IgG3 anti-fHbp MAbs had the greatest bactericidal activity. At a higher epitope density in the mutant, the IgG1 MAbs had similar or greater bactericidal activity than the IgG3 MAbs, and the activity was less dependent on the inhibition of fH binding than at a lower epitope density.

  16. Improved efficacy of soluble human receptor activator of nuclear factor kappa B (RANK) fusion protein by site-directed mutagenesis.

    Science.gov (United States)

    Son, Young Jun; Han, Jihye; Lee, Jae Yeon; Kim, HaHyung; Chun, Taehoon

    2015-06-01

    Soluble human receptor activator of nuclear factor kappa B fusion immunoglobulin (hRANK-Ig) has been considered as one of the therapeutic agents to treat osteoporosis or diseases associated with bone destruction by blocking the interaction between RANK and the receptor activator of nuclear factor kappa B ligand (RANKL). However, no scientific record showing critical amino acid residues within the structural interface between the human RANKL and RANK complex is yet available. In this study, we produced several mutants of hRANK-Ig by replacement of amino acid residue(s) and tested whether the mutants had increased binding affinity to human RANKL. Based on the results from flow cytometry and surface plasmon resonance analyses, the replacement of E(125) with D(125), or E(125) and C(127) with D(125) and F(127) within loop 3 of cysteine-rich domain 3 of hRANK-Ig increases binding affinity to human RANKL over the wild-type hRANK-Ig. This result may provide the first example of improvement in the efficacy of hRANK-Ig by protein engineering and may give additional information to understand a more defined structural interface between hRANK and RANKL.

  17. Receptor activator NFkappaB-ligand and osteoprotegerin protein expression in human periapical cysts and granulomas.

    Science.gov (United States)

    Menezes, Renato; Bramante, Clóvis Monteiro; da Silva Paiva, Katiúcia Batista; Letra, Ariadne; Carneiro, Everdan; Fernando Zambuzzi, Willian; Granjeiro, José Mauro

    2006-09-01

    The purpose of this study was to determine the expression of receptor activator of NFkappaB ligand (RANKL) and osteoprotegerin (OPG) associated with bone destruction in periapical cysts and granulomas. Forty human dental chronic periapical lesions were collected after periapical surgery. The lesions collected were fixed in 10% buffered formalin and histologically processed. At least 2 sections of each specimen were stained with hematoxylin and eosin for microscopic diagnosis. After that, 10 human periapical granulomas and 10 cysts were selected for immunohistochemical analysis for RANKL, OPG, and CD68+. Polymorphonuclear neutrophils, macrophages, endothelial cells, and lymphocytes were stained for RANKL and OPG in both lesions. Epithelial cells were also stained for RANKL and OPG in periapical cysts. Quantitative analysis was conducted and the results were expressed as a ratio of the number of immunostained cells over the total number of cells in the field (n = 100). The ratio of RANKL+/total cells was higher than OPG+/total cells in periapical granulomas (0.553 +/- 0.153 and 0.483 +/- 0.189, respectively; P cysts (0.519 +/- 0.09 and 0.339 +/- 0.117, respectively; P cysts. However, the ratio RANKL+/OPG+ in granulomas (1.336 +/- 0.723) and cysts (1.404 +/- 0.385) was not significantly different. The ratio of CD68+/total cells was significantly higher in granulomas (0.381 +/- 0.040) than in cysts (0.307 +/- 0.068) (P cysts and granulomas, strongly suggesting the involvement of these gene products in the development of periapical lesions.

  18. Expression and Activity of Breast Cancer Resistance Protein (BCRP/ABCG2) in Human Distal Lung Epithelial Cells In Vitro.

    Science.gov (United States)

    Nickel, Sabrina; Selo, Mohammed Ali; Fallack, Juliane; Clerkin, Caoimhe G; Huwer, Hanno; Schneider-Daum, Nicole; Lehr, Claus-Michael; Ehrhardt, Carsten

    2017-12-01

    Breast cancer resistance protein (BCRP/ABCG2) has previously been identified with high expression levels in human lung. The subcellular localisation and functional activity of the transporter in lung epithelia, however, remains poorly investigated. The aim of this project was to study BCRP expression and activity in freshly isolated human alveolar epithelial type 2 (AT2) and type 1-like (AT1-like) cells in primary culture, and to compare these findings with data obtained from the NCI-H441 cell line. BCRP expression levels in AT2 and AT1-like cells and in different passages of NCI-H441 cells were determined using q-PCR and immunoblot. Transporter localisation was confirmed by confocal laser scanning microscopy. Efflux and transport studies using the BCRP substrate BODIPY FL prazosin and the inhibitor Ko143 were carried out to assess BCRP activity in the different cell models. BCRP expression decreased during transdifferentiation from AT2 to AT1-like phenotype. Culturing NCI-H441 cells at an air-liquid interface or submersed did not change BCRP abundance, however, BCRP levels increased with passage number. BCRP was localised to the apical membrane and cytosol in NCI-H441 cells. In primary cells, the protein was found predominantly in the nucleus. Functional studies were consistent with expression data. BCRP is differently expressed in AT2 and AT1-like cells with lower abundance and activity in the latter ones. Nuclear BCRP might play a transcriptional role in distal lung epithelium. In NCI-H441 cells, BCRP is expressed in apical cell membranes and its activity is consistent with the localisation pattern.

  19. Protection of Human Podocytes from Shiga Toxin 2-Induced Phosphorylation of Mitogen-Activated Protein Kinases and Apoptosis by Human Serum Amyloid P Component

    Science.gov (United States)

    Dettmar, Anne K.; Binder, Elisabeth; Greiner, Friederike R.; Liebau, Max C.; Kurschat, Christine E.; Jungraithmayr, Therese C.; Saleem, Moin A.; Schmitt, Claus-Peter; Feifel, Elisabeth; Orth-Höller, Dorothea; Kemper, Markus J.; Pepys, Mark; Würzner, Reinhard

    2014-01-01

    Hemolytic uremic syndrome (HUS) is mainly induced by Shiga toxin 2 (Stx2)-producing Escherichia coli. Proteinuria can occur in the early phase of the disease, and its persistence determines the renal prognosis. Stx2 may injure podocytes and induce proteinuria. Human serum amyloid P component (SAP), a member of the pentraxin family, has been shown to protect against Stx2-induced lethality in mice in vivo, presumably by specific binding to the toxin. We therefore tested the hypothesis that SAP can protect against Stx2-induced injury of human podocytes. To elucidate the mechanisms underlying podocyte injury in HUS-associated proteinuria, we assessed Stx2-induced activation of mitogen-activated protein kinases (MAPKs) and apoptosis in immortalized human podocytes and evaluated the impact of SAP on Stx2-induced damage. Human podocytes express Stx2-binding globotriaosylceramide 3. Stx2 applied to cultured podocytes was internalized and then activated p38α MAPK and c-Jun N-terminal kinase (JNK), important signaling steps in cell differentiation and apoptosis. Stx2 also activated caspase 3, resulting in an increased level of apoptosis. Coincubation of podocytes with SAP and Stx2 mitigated the effects of Stx2 and induced upregulation of antiapoptotic Bcl2. These data suggest that podocytes are a target of Stx2 and that SAP protects podocytes against Stx2-induced injury. SAP may therefore be a useful therapeutic option. PMID:24566618

  20. In normal human fibroblasts variation in DSB repair capacity cannot be ascribed to radiation-induced changes in the localisation, expression or activity of major NHEJ proteins

    DEFF Research Database (Denmark)

    Kasten-Pisula, Ulla; Vronskaja, Svetlana; Overgaard, Jens

    2008-01-01

    in the activity of the DNA-PK complex induced upon irradiation. CONCLUSIONS: For normal human fibroblasts, the level or activity of NHEJ proteins measured prior to or after irradiation cannot be used to predict the DSB repair capacity or cellular radiosensitivity. Udgivelsesdato: 2008-Mar......BACKGROUND AND PURPOSE: The aim of the present study was to test whether for normal human fibroblasts the variation in double-strand break (DSB) repair capacity results from radiation-induced differences in localisation, expression or activity of major non-homologous end-joining (NHEJ) proteins....... MATERIALS AND METHODS: Experiments were performed with 11 normal human fibroblast strains AF01-11. NHEJ proteins were determined by Western blot and DNA-PK activity by pulldown-assay. RESULTS: The four NHEJ proteins tested (Ku70, Ku80, XRCC4 and DNA-PKcs) were found to be localised almost exclusively...

  1. Organization of the gene coding for human protein C inhibitor (plasminogen activator inhibitor-3). Assignment of the gene to chromosome 14

    NARCIS (Netherlands)

    Meijers, J. C.; Chung, D. W.

    1991-01-01

    Protein C inhibitor (plasminogen activator inhibitor-3) is a plasma glycoprotein and a member of the serine proteinase inhibitor superfamily. In the present study, the human gene for protein C inhibitor was isolated and characterized from three independent phage that contained overlapping inserts

  2. Zinc binding activity of human metapneumovirus M2-1 protein is indispensable for viral replication and pathogenesis in vivo.

    Science.gov (United States)

    Cai, Hui; Zhang, Yu; Ma, Yuanmei; Sun, Jing; Liang, Xueya; Li, Jianrong

    2015-06-01

    Human metapneumovirus (hMPV) is a member of the Pneumovirinae subfamily in the Paramyxoviridae family that causes respiratory tract infections in humans. Unlike members of the Paramyxovirinae subfamily, the polymerase complex of pneumoviruses requires an additional cofactor, the M2-1 protein, which functions as a transcriptional antitermination factor. The M2-1 protein was found to incorporate zinc ions, although the specific role(s) of the zinc binding activity in viral replication and pathogenesis remains unknown. In this study, we found that the third cysteine (C21) and the last histidine (H25) in the zinc binding motif (CCCH) of hMPV M2-1 were essential for zinc binding activity, whereas the first two cysteines (C7 and C15) play only minor or redundant roles in zinc binding. In addition, the zinc binding motif is essential for the oligomerization of M2-1. Subsequently, recombinant hMPVs (rhMPVs) carrying mutations in the zinc binding motif were recovered. Interestingly, rhMPV-C21S and -H25L mutants, which lacked zinc binding activity, had delayed replication in cell culture and were highly attenuated in cotton rats. In contrast, rhMPV-C7S and -C15S strains, which retained 60% of the zinc binding activity, replicated as efficiently as rhMPV in cotton rats. Importantly, rhMPVs that lacked zinc binding activity triggered high levels of neutralizing antibody and provided complete protection against challenge with rhMPV. Taken together, these results demonstrate that zinc binding activity is indispensable for viral replication and pathogenesis in vivo. These results also suggest that inhibition of zinc binding activity may serve as a novel approach to rationally attenuate hMPV and perhaps other pneumoviruses for vaccine purposes. The pneumoviruses include many important human and animal pathogens, such as human respiratory syncytial virus (hRSV), hMPV, bovine RSV, and avian metapneumovirus (aMPV). Among these viruses, hRSV and hMPV are the leading causes of acute

  3. Multiplexed activity-based protein profiling of the human pathogen Aspergillus fumigatus reveals large functional changes upon exposure to human serum.

    Science.gov (United States)

    Wiedner, Susan D; Burnum, Kristin E; Pederson, LeeAnna M; Anderson, Lindsey N; Fortuin, Suereta; Chauvigné-Hines, Lacie M; Shukla, Anil K; Ansong, Charles; Panisko, Ellen A; Smith, Richard D; Wright, Aaron T

    2012-09-28

    Environmental adaptability is critical for survival of the fungal human pathogen Aspergillus fumigatus in the immunocompromised host lung. We hypothesized that exposure of the fungal pathogen to human serum would lead to significant alterations to the organism's physiology, including metabolic activity and stress response. Shifts in functional pathway and corresponding enzyme reactivity of A. fumigatus upon exposure to the human host may represent much needed prognostic indicators of fungal infection. To address this, we employed a multiplexed activity-based protein profiling (ABPP) approach coupled to quantitative mass spectrometry-based proteomics to measure broad enzyme reactivity of the fungus cultured with and without human serum. ABPP showed a shift from aerobic respiration to ethanol fermentation and utilization over time in the presence of human serum, which was not observed in serum-free culture. Our approach provides direct insight into this pathogen's ability to survive, adapt, and proliferate. Additionally, our multiplexed ABPP approach captured a broad swath of enzyme reactivity and functional pathways and provides a method for rapid assessment of the A. fumigatus response to external stimuli.

  4. Multiplexed Activity-based Protein Profiling of the Human Pathogen Aspergillus fumigatus Reveals Large Functional Changes upon Exposure to Human Serum*

    Science.gov (United States)

    Wiedner, Susan D.; Burnum, Kristin E.; Pederson, LeeAnna M.; Anderson, Lindsey N.; Fortuin, Suereta; Chauvigné-Hines, Lacie M.; Shukla, Anil K.; Ansong, Charles; Panisko, Ellen A.; Smith, Richard D.; Wright, Aaron T.

    2012-01-01

    Environmental adaptability is critical for survival of the fungal human pathogen Aspergillus fumigatus in the immunocompromised host lung. We hypothesized that exposure of the fungal pathogen to human serum would lead to significant alterations to the organism's physiology, including metabolic activity and stress response. Shifts in functional pathway and corresponding enzyme reactivity of A. fumigatus upon exposure to the human host may represent much needed prognostic indicators of fungal infection. To address this, we employed a multiplexed activity-based protein profiling (ABPP) approach coupled to quantitative mass spectrometry-based proteomics to measure broad enzyme reactivity of the fungus cultured with and without human serum. ABPP showed a shift from aerobic respiration to ethanol fermentation and utilization over time in the presence of human serum, which was not observed in serum-free culture. Our approach provides direct insight into this pathogen's ability to survive, adapt, and proliferate. Additionally, our multiplexed ABPP approach captured a broad swath of enzyme reactivity and functional pathways and provides a method for rapid assessment of the A. fumigatus response to external stimuli. PMID:22865858

  5. Constitutively active signaling by the G protein βγ-subunit mediates intrinsically increased phosphodiesterase-4 activity in human asthmatic airway smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Aihua Hu

    Full Text Available Signaling by the Gβγ subunit of Gi protein, leading to downstream c-Src-induced activation of the Ras/c-Raf1/MEK-ERK1/2 signaling pathway and its upregulation of phosphodiesterase-4 (PDE4 activity, was recently shown to mediate the heightened contractility in proasthmatic sensitized isolated airway smooth muscle (ASM, as well as allergen-induced airway hyperresponsiveness and inflammation in an in vivo animal model of allergic asthma. This study investigated whether cultured human ASM (HASM cells derived from asthmatic donor lungs exhibit constitutively increased PDE activity that is attributed to intrinsically upregulated Gβγ signaling coupled to c-Src activation of the Ras/MEK/ERK1/2 cascade. We show that, relative to normal cells, asthmatic HASM cells constitutively exhibit markedly increased intrinsic PDE4 activity coupled to heightened Gβγ-regulated phosphorylation of c-Src and ERK1/2, and direct co-localization of the latter with the PDE4D isoform. These signaling events and their induction of heightened PDE activity are acutely suppressed by treating asthmatic HASM cells with a Gβγ inhibitor. Importantly, along with increased Gβγ activation, asthmatic HASM cells also exhibit constitutively increased direct binding of the small Rap1 GTPase-activating protein, Rap1GAP, to the α-subunit of Gi protein, which serves to cooperatively facilitate Ras activation and, thereby, enable enhanced Gβγ-regulated ERK1/2-stimulated PDE activity. Collectively, these data are the first to identify that intrinsically increased signaling via the Gβγ subunit, facilitated by Rap1GAP recruitment to the α-subunit, mediates the constitutively increased PDE4 activity detected in asthmatic HASM cells. These new findings support the notion that interventions targeted at suppressing Gβγ signaling may lead to novel approaches to treat asthma.

  6. AMP-activated protein kinase-mediated glucose transport as a novel target of tributyltin in human embryonic carcinoma cells.

    Science.gov (United States)

    Yamada, Shigeru; Kotake, Yaichiro; Sekino, Yuko; Kanda, Yasunari

    2013-05-01

    Organotin compounds such as tributyltin (TBT) are known to cause various forms of cytotoxicity, including developmental toxicity and neurotoxicity. However, the molecular target of the toxicity induced by nanomolar levels of TBT has not been identified. In the present study, we found that exposure to 100 nM TBT induced growth arrest in human pluripotent embryonic carcinoma cell line NT2/D1. Since glucose provides metabolic energy, we focused on the glycolytic system. We found that exposure to TBT reduced the levels of both glucose-6-phosphate and fructose-6-phosphate. To investigate the effect of TBT exposure on glycolysis, we examined glucose transporter (GLUT) activity. TBT exposure inhibited glucose uptake via a decrease in the level of cell surface-bound GLUT1. Furthermore, we examined the effect of AMP-activated protein kinase (AMPK), which is known to regulate glucose transport by facilitating GLUT translocation. Treatment with the potent AMPK activator, AICAR, restored the TBT-induced reduction in cell surface-bound GLUT1 and glucose uptake. In conclusion, these results suggest that exposure to nanomolar levels of TBT causes growth arrest by targeting glycolytic systems in human embryonic carcinoma cells. Thus, understanding the energy metabolism may provide new insights into the mechanisms of metal-induced cytotoxicity.

  7. Spaceflight Activates Protein Kinase C Alpha Signaling and Modifies the Developmental Stage of Human Neonatal Cardiovascular Progenitor Cells.

    Science.gov (United States)

    Baio, Jonathan; Martinez, Aida F; Bailey, Leonard; Hasaniya, Nahidh; Pecaut, Michael J; Kearns-Jonker, Mary

    2018-02-12

    Spaceflight impacts cardiovascular function in astronauts; however, its impact on cardiac development and the stem cells that form the basis for cardiac repair is unknown. Accordingly, further research is needed to uncover the potential relevance of such changes to human health. Using simulated microgravity (SMG) generated by two-dimensional clinorotation and culture aboard the International Space Station (ISS), we assessed the effects of mechanical unloading on human neonatal cardiovascular progenitor cell (CPC) developmental properties and signaling. Following 6-7 days of SMG and 12 days of ISS culture, we analyzed changes in gene expression. Both environments induced the expression of genes that are typically associated with an earlier state of cardiovascular development. To understand the mechanism by which such changes occurred, we assessed the expression of mechanosensitive small RhoGTPases in SMG-cultured CPCs and observed decreased levels of RHOA and CDC42. Given the effect of these molecules on intracellular calcium levels, we evaluated changes in noncanonical Wnt/calcium signaling. After 6-7 days under SMG, CPCs exhibited elevated levels of WNT5A and PRKCA. Similarly, ISS-cultured CPCs exhibited elevated levels of calcium handling and signaling genes, which corresponded to protein kinase C alpha (PKCα), a calcium-dependent protein kinase, activation after 30 days. Akt was activated, whereas phosphorylated extracellular signal-regulated kinase levels were unchanged. To explore the effect of calcium induction in neonatal CPCs, we activated PKCα using hWnt5a treatment on Earth. Subsequently, early cardiovascular developmental marker levels were elevated. Transcripts induced by SMG and hWnt5a-treatment are expressed within the sinoatrial node, which may represent embryonic myocardium maintained in its primitive state. Calcium signaling is sensitive to mechanical unloading and directs CPC developmental properties. Further research both in space and on Earth

  8. Human herpesvirus 6B U19 protein is a PML-regulated transcriptional activator that localizes to nuclear foci in a PML-independent manner

    DEFF Research Database (Denmark)

    Kofod-Olsen, Emil; Ross-Hansen, Katrine; Mikkelsen, Jacob Giehm

    2008-01-01

    Human herpesvirus 6B (HHV-6B) contains an IE-B domain spanning open reading frames U16/17-U19, based on homology with human cytomegalovirus. Here, the protein product, U19, of the HHV-6B U19 gene is identified as a 47 kDa transcriptional activator. HHV-6B infection or overexpression of U19...

  9. The human papillomavirus type 16 E6 oncoprotein activates mTORC1 signaling and increases protein synthesis.

    Science.gov (United States)

    Spangle, Jennifer M; Münger, Karl

    2010-09-01

    The mammalian target of rapamycin (mTOR) kinase acts as a cellular rheostat that integrates signals from a variety of cellular signal transduction pathways that sense growth factor and nutrient availability as well as intracellular energy status. It was previously reported that the human papillomavirus type 16 (HPV16) E6 oncoprotein may activate the S6 protein kinase (S6K) through binding and E6AP-mediated degradation of the mTOR inhibitor tuberous sclerosis complex 2 (TSC2) (Z. Lu, X. Hu, Y. Li, L. Zheng, Y. Zhou, H. Jiang, T. Ning, Z. Basang, C. Zhang, and Y. Ke, J. Biol. Chem. 279:35664-35670, 2004; L. Zheng, H. Ding, Z. Lu, Y. Li, Y. Pan, T. Ning, and Y. Ke, Genes Cells 13:285-294, 2008). Our results confirmed that HPV16 E6 expression causes an increase in mTORC1 activity through enhanced phosphorylation of mTOR and activation of downstream signaling pathways S6K and eukaryotic initiation factor binding protein 1 (4E-BP1). However, we did not detect a decrease in TSC2 levels in HPV16 E6-expressing cells. We discovered, however, that HPV16 E6 expression causes AKT activation through the upstream kinases PDK1 and mTORC2 under conditions of nutrient deprivation. We show that HPV16 E6 expression causes an increase in protein synthesis by enhancing translation initiation complex assembly at the 5' mRNA cap and an increase in cap-dependent translation. The increase in cap-dependent translation likely results from HPV16 E6-induced AKT/mTORC1 activation, as the assembly of the translation initiation complex and cap-dependent translation are rapamycin sensitive. Lastly, coexpression of the HPV16 E6 and E7 oncoproteins does not affect HPV16 E6-induced activation of mTORC1 and cap-dependent translation. HPV16 E6-mediated activation of mTORC1 signaling and cap-dependent translation may be a mechanism to promote viral replication under conditions of limited nutrient supply in differentiated, HPV oncoprotein-expressing proliferating cells.

  10. AMP-Activated Protein Kinase Interacts with the Peroxisome Proliferator-Activated Receptor Delta to Induce Genes Affecting Fatty Acid Oxidation in Human Macrophages.

    Directory of Open Access Journals (Sweden)

    Marina Kemmerer

    Full Text Available AMP-activated protein kinase (AMPK maintains energy homeostasis by suppressing cellular ATP-consuming processes and activating catabolic, ATP-producing pathways such as fatty acid oxidation (FAO. The transcription factor peroxisome proliferator-activated receptor δ (PPARδ also affects fatty acid metabolism, stimulating the expression of genes involved in FAO. To question the interplay of AMPK and PPARδ in human macrophages we transduced primary human macrophages with lentiviral particles encoding for the constitutively active AMPKα1 catalytic subunit, followed by microarray expression analysis after treatment with the PPARδ agonist GW501516. Microarray analysis showed that co-activation of AMPK and PPARδ increased expression of FAO genes, which were validated by quantitative PCR. Induction of these FAO-associated genes was also observed upon infecting macrophages with an adenovirus coding for AMPKγ1 regulatory subunit carrying an activating R70Q mutation. The pharmacological AMPK activator A-769662 increased expression of several FAO genes in a PPARδ- and AMPK-dependent manner. Although GW501516 significantly increased FAO and reduced the triglyceride amount in very low density lipoproteins (VLDL-loaded foam cells, AMPK activation failed to potentiate this effect, suggesting that increased expression of fatty acid catabolic genes alone may be not sufficient to prevent macrophage lipid overload.

  11. Effects of vitamin D-binding protein-derived macrophage-activating factor on human breast cancer cells.

    Science.gov (United States)

    Pacini, Stefania; Punzi, Tiziana; Morucci, Gabriele; Gulisano, Massimo; Ruggiero, Marco

    2012-01-01

    Searching for additional therapeutic tools to fight breast cancer, we investigated the effects of vitamin D-binding protein-derived macrophage activating factor (DBP-MAF, also known as GcMAF) on a human breast cancer cell line (MCF-7). The effects of DBP-MAF on proliferation, morphology, vimentin expression and angiogenesis were studied by cell proliferation assay, phase-contrast microscopy, immunohistochemistry and western blotting, and chorioallantoic membrane (CAM) assay. DBP-MAF inhibited human breast cancer cell proliferation and cancer cell-stimulated angiogenesis. MCF-7 cells treated with DBP-MAF predominantly grew in monolayer and appeared to be well adherent to each other and to the well surface. Exposure to DBP-MAF significantly reduced vimentin expression, indicating a reversal of the epithelial/mesenchymal transition, a hallmark of human breast cancer progression. These results are consistent with the hypothesis that the known anticancer efficacy of DBP-MAF can be ascribed to different biological properties of the molecule that include inhibition of tumour-induced angiogenesis and direct inhibition of cancer cell proliferation, migration and metastatic potential.

  12. Activating human genes with zinc finger proteins, transcription activator-like effectors and CRISPR/Cas9 for gene therapy and regenerative medicine.

    Science.gov (United States)

    Gersbach, Charles A; Perez-Pinera, Pablo

    2014-08-01

    New technologies have recently been developed to control the expression of human genes in their native genomic context by engineering synthetic transcription factors that can be targeted to any DNA sequence. The ability to precisely regulate any gene as it occurs naturally in the genome provides a means to address a variety of diseases and disorders. This approach also circumvents some of the traditional challenges of gene therapy. In this editorial, we review the technologies that have enabled targeted human gene activation, including the engineering of transcription factors based on zinc finger proteins, transcription activator-like effectors and the CRISPR/Cas9 system. Additionally, we highlight examples in which these methods have been developed for therapeutic applications and discuss challenges and opportunities.

  13. Down-Regulation of Na+/K+ ATPase Activity by Human Parvovirus B19 Capsid Protein VP1

    Directory of Open Access Journals (Sweden)

    Ahmad Almilaji

    2013-05-01

    Full Text Available Background/Aims: Human parvovirus B19 (B19V may cause inflammatory cardiomyopathy (iCMP which is accompanied by endothelial dysfunction. The B19V capsid protein VP1 contains a lysophosphatidylcholine producing phospholipase A2 (PLA sequence. Lysophosphatidylcholine has in turn been shown to inhibit Na+/K+ ATPase. The present study explored whether VP1 modifies Na+/K+ ATPase activity. Methods: Xenopus oocytes were injected with cRNA encoding VP1 isolated from a patient suffering from fatal B19V-iCMP or cRNA encoding PLA2-negative VP1 mutant (H153A and K+ induced pump current (Ipump as well as ouabain-inhibited current (Iouabain both reflecting Na+/K+-ATPase activity were determined by dual electrode voltage clamp. Results: Injection of cRNA encoding VP1, but not of VP1(H153A or water, was followed by a significant decrease of both, Ipump and Iouabain in Xenopus oocytes. The effect was not modified by inhibition of transcription with actinomycin (10 µM for 36 hours but was abrogated in the presence of PLA2 specific blocker 4-bromophenacylbromide (50 µM and was mimicked by lysophosphatidylcholine (0.5 - 1 µg/ml. According to whole cell patch clamp, lysophosphatidylcholine (1 µg /ml similarly decreased Ipump in human microvascular endothelial cells (HMEC. Conclusion: The B19V capsid protein VP1 is a powerful inhibitor of host cell Na+/K+ ATPase, an effect at least partially due to phospholipase A2 (PLA2 dependent formation of lysophosphatidylcholine.

  14. The next generation of sepsis clinical trial designs: what is next after the demise of recombinant human activated protein C?*.

    Science.gov (United States)

    Opal, Steven M; Dellinger, R Phillip; Vincent, Jean-Louis; Masur, Henry; Angus, Derek C

    2014-07-01

    The developmental pipeline for novel therapeutics to treat sepsis has diminished to a trickle compared to previous years of sepsis research. While enormous strides have been made in understanding the basic molecular mechanisms that underlie the pathophysiology of sepsis, a long list of novel agents have now been tested in clinical trials without a single immunomodulating therapy showing consistent benefit. The only antisepsis agent to successfully complete a phase III clinical trial was human recumbent activated protein C. This drug was taken off the market after a follow-up placebo-controlled trial (human recombinant activated Protein C Worldwide Evaluation of Severe Sepsis and septic Shock [PROWESS SHOCK]) failed to replicate the favorable results of the initial registration trial performed ten years earlier. We must critically reevaluate our basic approach to the preclinical and clinical evaluation of new sepsis therapies. We selected the major clinical studies that investigated interventional trials with novel therapies to treat sepsis over the last 30 years. Phase II and phase III trials investigating new treatments for sepsis and editorials and critiques of these studies. Selected manuscripts and clinical study reports were analyzed from sepsis trials. Specific shortcomings and potential pit falls in preclinical evaluation and clinical study design and analysis were reviewed and synthesized. After review and discussion, a series of 12 recommendations were generated with suggestions to guide future studies with new treatments for sepsis. We need to improve our ability to define appropriate molecular targets for preclinical development and develop better methods to determine the clinical value of novel sepsis agents. Clinical trials must have realistic sample sizes and meaningful endpoints. Biomarker-driven studies should be considered to categorize specific "at risk" populations most likely to benefit from a new treatment. Innovations in clinical trial design

  15. AT-406, an orally active antagonist of multiple inhibitor of apoptosis proteins, inhibits progression of human ovarian cancer.

    Science.gov (United States)

    Brunckhorst, Melissa K; Lerner, Dimitry; Wang, Shaomeng; Yu, Qin

    2012-07-01

    Ovarian carcinoma is the most deadly gynecological malignancy. Current chemotherapeutic drugs are only transiently effective and patients with advance disease often develop resistance despite significant initial responses. Mounting evidence suggests that anti-apoptotic proteins, including those of the inhibitor of apoptosis protein (IAP) family, play important roles in the chemoresistance. There has been a recent emergence of compounds that block the IAP functions. Here, we evaluated AT-406, a novel and orally active antagonist of multiple IAP proteins, in ovarian cancer cells as a single agent and in the combination with carboplatin for therapeutic efficacy and mechanism of action. We demonstrate that AT-406 has significant single agent activity in 60% of human ovarian cancer cell lines examined in vitro and inhibits ovarian cancer progression in vivo and that 3 out of 5 carboplatin-resistant cell lines are sensitive to AT-406, highlighting the therapeutic potential of AT-406 for patients with inherent or acquired platinum resistance. Additionally, our in vivo studies show that AT-406 enhances the carboplatin-induced ovarian cancer cell death and increases survival of the experimental mice, suggesting that AT-406 sensitizes the response of these cells to carboplatin. Mechanistically, we demonstrate that AT-406 induced apoptosis is correlated with its ability to down-regulate XIAP whereas AT-406 induces cIAP1 degradation in both AT-406 sensitive and resistance cell lines. Together, these results demonstrate, for the first time, the anti-ovarian cancer efficacy of AT-406 as a single agent and in the combination with carboplatin, suggesting that AT-406 has potential as a novel therapy for ovarian cancer patients, especially for patients exhibiting resistance to the platinum-based therapies.

  16. Resveratrol serves as a protein-substrate interaction stabilizer in human SIRT1 activation

    Science.gov (United States)

    Hou, Xuben; Rooklin, David; Fang, Hao; Zhang, Yingkai

    2016-11-01

    Resveratrol is a natural compound found in red wine that has been suggested to exert its potential health benefit through the activation of SIRT1, a crucial member of the mammalian NAD+-dependent deacetylases. SIRT1 has emerged as an attractive therapeutic target for many aging related diseases, however, how its activity can only be activated toward some specific substrates by resveratrol has been poorly understood. Herein, by employing extensive molecular dynamics simulations as well as fragment-centric topographical mapping of binding interfaces, we have clarified current controversies in the literature and elucidated that resveratrol plays an important activation role by stabilizing SIRT1/peptide interactions in a substrate-specific manner. This new mechanism highlights the importance of the N-terminal domain in substrate recognition, explains the activity restoration role of resveratrol toward some “loose-binding” substrates of SIRT1, and has significant implications for the rational design of new substrate-specific SIRT1 modulators.

  17. Neuropeptide Y, substance P, and human bone morphogenetic protein 2 stimulate human osteoblast osteogenic activity by enhancing gap junction intercellular communication

    International Nuclear Information System (INIS)

    Ma, W.H.; Liu, Y.J.; Wang, W.; Zhang, Y.Z.

    2015-01-01

    Bone homeostasis seems to be controlled by delicate and subtle “cross talk” between the nervous system and “osteo-neuromediators” that control bone remodeling. The purpose of this study was to evaluate the effect of interactions between neuropeptides and human bone morphogenetic protein 2 (hBMP2) on human osteoblasts. We also investigated the effects of neuropeptides and hBMP2 on gap junction intercellular communication (GJIC). Osteoblasts were treated with neuropeptide Y (NPY), substance P (SP), or hBMP2 at three concentrations. At various intervals after treatment, cell viability was measured by the MTT assay. In addition, cellular alkaline phosphatase (ALP) activity and osteocalcin were determined by colorimetric assay and radioimmunoassay, respectively. The effects of NPY, SP and hBMP on GJIC were determined by laser scanning confocal microscopy. The viability of cells treated with neuropeptides and hBMP2 increased significantly in a time-dependent manner, but was inversely associated with the concentration of the treatments. ALP activity and osteocalcin were both reduced in osteoblasts exposed to the combination of neuropeptides and hBMP2. The GJIC of osteoblasts was significantly increased by the neuropeptides and hBMP2. These results suggest that osteoblast activity is increased by neuropeptides and hBMP2 through increased GJIC. Identification of the GJIC-mediated signal transduction capable of modulating the cellular activities of bone cells represents a novel approach to studying the biology of skeletal innervation

  18. Neuropeptide Y, substance P, and human bone morphogenetic protein 2 stimulate human osteoblast osteogenic activity by enhancing gap junction intercellular communication

    Energy Technology Data Exchange (ETDEWEB)

    Ma, W.H.; Liu, Y.J.; Wang, W.; Zhang, Y.Z. [The Third Hospital of Hebei Medical University, The Provincial Key Laboratory for Orthopedic Biomechanics of Hebei, Shijiazhuang, Hebei Province (China)

    2015-02-13

    Bone homeostasis seems to be controlled by delicate and subtle “cross talk” between the nervous system and “osteo-neuromediators” that control bone remodeling. The purpose of this study was to evaluate the effect of interactions between neuropeptides and human bone morphogenetic protein 2 (hBMP2) on human osteoblasts. We also investigated the effects of neuropeptides and hBMP2 on gap junction intercellular communication (GJIC). Osteoblasts were treated with neuropeptide Y (NPY), substance P (SP), or hBMP2 at three concentrations. At various intervals after treatment, cell viability was measured by the MTT assay. In addition, cellular alkaline phosphatase (ALP) activity and osteocalcin were determined by colorimetric assay and radioimmunoassay, respectively. The effects of NPY, SP and hBMP on GJIC were determined by laser scanning confocal microscopy. The viability of cells treated with neuropeptides and hBMP2 increased significantly in a time-dependent manner, but was inversely associated with the concentration of the treatments. ALP activity and osteocalcin were both reduced in osteoblasts exposed to the combination of neuropeptides and hBMP2. The GJIC of osteoblasts was significantly increased by the neuropeptides and hBMP2. These results suggest that osteoblast activity is increased by neuropeptides and hBMP2 through increased GJIC. Identification of the GJIC-mediated signal transduction capable of modulating the cellular activities of bone cells represents a novel approach to studying the biology of skeletal innervation.

  19. The proteolytic activity of pregnancy-associated plasma protein-A is potentially regulated by stanniocalcin-1 and -2 during human ovarian follicle development

    DEFF Research Database (Denmark)

    Jepsen, Malene R.; Kløverpris, Søren; Bøtkjær, Jane A.

    2016-01-01

    STUDY QUESTION: Is the proteolytic activity of pregnancy-associated plasma protein-A (PAPP-A) regulated by the stanniocalcins (STC1 and STC2) during human follicle maturation? SUMMARY ANSWER: The STCs and PAPP-A show similar expression by immunohistochemistry in developing follicles, and regulation...... of PAPP-A proteolytic activity is suggested by the identification of inhibited protein complexes between PAPP-A and STC1 or STC2 in human follicular fluid (FF). WHAT IS KNOWN ALREADY: The insulin-like growth factor (IGF)-regulating proteinase PAPP-A is secreted by the granulosa cells of estrogen...

  20. Protein phosphorylation systems in postmortem human brain

    International Nuclear Information System (INIS)

    Walaas, S.I.; Perdahl-Wallace, E.; Winblad, B.; Greengard, P.

    1989-01-01

    Protein phosphorylation systems regulated by cyclic adenosine 3',5'-monophosphate (cyclic AMP), or calcium in conjunction with calmodulin or phospholipid/diacylglycerol, have been studied by phosphorylation in vitro of particulate and soluble fractions from human postmortem brain samples. One-dimensional or two-dimensional gel electrophoretic protein separations were used for analysis. Protein phosphorylation catalyzed by cyclic AMP-dependent protein kinase was found to be highly active in both particulate and soluble preparations throughout the human CNS, with groups of both widely distributed and region-specific substrates being observed in different brain nuclei. Dopamine-innervated parts of the basal ganglia and cerebral cortex contained the phosphoproteins previously observed in rodent basal ganglia. In contrast, calcium/phospholipid-dependent and calcium/calmodulin-dependent protein phosphorylation systems were less prominent in human postmortem brain than in rodent brain, and only a few widely distributed substrates for these protein kinases were found. Protein staining indicated that postmortem proteolysis, particularly of high-molecular-mass proteins, was prominent in deeply located, subcortical regions in the human brain. Our results indicate that it is feasible to use human postmortem brain samples, when obtained under carefully controlled conditions, for qualitative studies on brain protein phosphorylation. Such studies should be of value in studies on human neurological and/or psychiatric disorders

  1. Analysis of translesion DNA synthesis activity of the human REV1 protein, which is a key player in radiation-induced mutagenesis

    International Nuclear Information System (INIS)

    Masuda, Yuji; Kamiya, Kenji

    2003-01-01

    Ionizing radiation frequently causes oxidative DNA damage in cells. It has been suggested that functions of the REV1 gene are induction of mutations and prevention of cell death caused by ionizing radiation through the damage bypass DNA replication. The gene product possesses a deoxycytidyl transferase activity, which is required for translesion DNA synthesis of a variety of damaged bases and an abasic site. To elucidate molecular mechanisms of the mutagenesis and translesion DNA synthesis, it is important to characterize the enzymatic properties of the REV1 protein. Here, we describe a novel method for purifying the recombinant human REV1 protein and the anzymatic properties of the protein. We established an efficient system for induction of the recombinant human REV1 protein in Escherichia coli cells. The REV1 protein was purified to homogeneity using nickel-chelating sepharose, heparin sepharose and superdex 200 chromatography. When purified by this method, REV1 protein is free of endo-, exonuclease and DNA polymerase activities. The purified REV1 protein is suitable for enzymological studies, and we used this to biochemical characterization. The REV1 protein inserts dCMP opposite templates G, A, T, C and an abasic site and inserts dGMP and dTMP opposite template G. Kinetic analysis provided evidence for high efficiency for dCMP insertion opposite template G and an abasic site, suggesting that the REV1 protein play a role in translesion DNA synthesis of an abasic site. (author)

  2. Telmisartan enhances mitochondrial activity and alters cellular functions in human coronary artery endothelial cells via AMP-activated protein kinase pathway.

    Science.gov (United States)

    Kurokawa, Hirofumi; Sugiyama, Seigo; Nozaki, Toshimitsu; Sugamura, Koichi; Toyama, Kensuke; Matsubara, Junichi; Fujisue, Koichiro; Ohba, Keisuke; Maeda, Hirofumi; Konishi, Masaaki; Akiyama, Eiichi; Sumida, Hitoshi; Izumiya, Yasuhiro; Yasuda, Osamu; Kim-Mitsuyama, Shokei; Ogawa, Hisao

    2015-04-01

    Mitochondrial dysfunction plays an important role in cellular senescence and impaired function of vascular endothelium, resulted in cardiovascular diseases. Telmisartan is a unique angiotensin II type I receptor blocker that has been shown to prevent cardiovascular events in high risk patients. AMP-activated protein kinase (AMPK) plays a critical role in mitochondrial biogenesis and endothelial function. This study assessed whether telmisartan enhances mitochondrial function and alters cellular functions via AMPK in human coronary artery endothelial cells (HCAECs). In cultured HCAECs, telmisartan significantly enhanced mitochondrial activity assessed by mitochondrial reductase activity and intracellular ATP production and increased the expression of mitochondria related genes. Telmisartan prevented cellular senescence and exhibited the anti-apoptotic and pro-angiogenic properties. The expression of genes related anti-oxidant and pro-angiogenic properties were increased by telmisartan. Telmisartan increased endothelial NO synthase and AMPK phosphorylation. Peroxisome proliferator-activated receptor gamma signaling was not involved in telmisartan-induced improvement of mitochondrial function. All of these effects were abolished by inhibition of AMPK. Telmisartan enhanced mitochondrial activity and exhibited anti-senescence effects and improving endothelial function through AMPK in HCAECs. Telmisartan could provide beneficial effects on vascular diseases via enhancement of mitochondrial activity and modulating endothelial function through AMPK activation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  3. Phosphorylation of human link proteins

    International Nuclear Information System (INIS)

    Oester, D.A.; Caterson, B.; Schwartz, E.R.

    1986-01-01

    Three link proteins of 48, 44 and 40 kDa were purified from human articular cartilage and identified with monoclonal anti-link protein antibody 8-A-4. Two sets of lower molecular weight proteins of 30-31 kDa and 24-26 kDa also contained link protein epitopes recognized by the monoclonal antibody and were most likely degradative products of the intact link proteins. The link proteins of 48 and 40 kDa were identified as phosphoproteins while the 44 kDa link protein did not contain 32 P. The phosphorylated 48 and 40 kDa link proteins contained approximately 2 moles PO 4 /mole link protein

  4. Extremely stable soluble high molecular mass multi-protein complex with DNase activity in human placental tissue.

    Directory of Open Access Journals (Sweden)

    Evgeniya E Burkova

    Full Text Available Human placenta is an organ which protects, feeds, and regulates the grooving of the embryo. Therefore, identification and characterization of placental components including proteins and their multi-protein complexes is an important step to understanding the placenta function. We have obtained and analyzed for the first time an extremely stable multi-protein complex (SPC, ∼ 1000 kDa from the soluble fraction of three human placentas. By gel filtration on Sepharose-4B, the SPC was well separated from other proteins of the placenta extract. Light scattering measurements and gel filtration showed that the SPC is stable in the presence of NaCl, MgCl2, acetonitrile, guanidinium chloride, and Triton in high concentrations, but dissociates efficiently in the presence of 8 M urea, 50 mM EDTA, and 0.5 M NaCl. Such a stable complex is unlikely to be a casual associate of different proteins. According to SDS-PAGE and MALDI mass spectrometry data, this complex contains many major glycosylated proteins with low and moderate molecular masses (MMs 4-14 kDa and several moderately abundant (79.3, 68.5, 52.8, and 27.2 kDa as well as minor proteins with higher MMs. The SPC treatment with dithiothreitol led to a disappearance of some protein bands and revealed proteins with lower MMs. The SPCs from three placentas efficiently hydrolyzed plasmid supercoiled DNA with comparable rates and possess at least two DNA-binding sites with different affinities for a 12-mer oligonucleotide. Progress in study of placental protein complexes can promote understanding of their biological functions.

  5. Moringa oleifera fruit induce apoptosis via reactive oxygen species-dependent activation of mitogen-activated protein kinases in human melanoma A2058 cells.

    Science.gov (United States)

    Guon, Tae Eun; Chung, Ha Sook

    2017-08-01

    The present study was performed to determine the effect of Moringa oleifera fruit extract on the apoptosis of human melanoma A2058 cells. A2058 cells were treated for 72 h with Moringa oleifera fruit extract at 50-100 µg/ml, and cell viability with apoptotic changes was examined. The involvement of reactive oxygen species (ROS) and mitogen-activated protein kinases (MAPKs) was examined. It was revealed that Moringa oleifera fruit extract significantly inhibited the cell viability and promoted apoptosis of A2058 cells in a concentration-dependent manner. Moringa oleifera fruit extract-treated A2058 cells exhibited increased activities of cleaved caspase-9 and caspase-3. It also caused an enhancement of MAPK phosphorylation and ROS production. The pro-apoptotic activity of Moringa oleifera fruit extract was significantly reversed by pretreatment with the c-Jun N-terminal kinase (JNK) inhibitor SP600125, extracellular-signal-regulated kinase (ERK) inhibitor PD98058 or ROS inhibitor N-acetyl-L-cysteine. Taken together, Moringa oleifera fruit extract is effective in inducing mitochondrial apoptosis of A2058 cells, which is mediated through induction of ROS formation, and JNK and ERK activation. Moringa oleifera fruit extract may thus have therapeutic benefits for human melanoma A2058 cells.

  6. Efficacy and effectiveness of recombinant human activated protein C in severe sepsis of adults

    Directory of Open Access Journals (Sweden)

    Greiner, Wolfgang

    2007-07-01

    Full Text Available Introduction: Sepsis is defined as an invasion of microorganisms and/or their toxins into the blood associated the reaction of the organism to this invasion. Severe sepsis is a major cost driver in intensive care medicine. In Germany, prevalence data was assessed in the context of the German Prevalence Study. Severe sepsis has a prevalence of 35% in German intensive care units. Research questions: The following questions were analysed: is Drotrecogin alfa (activated (DAA effective in the treatment of patients with severe sepsis and a mixed risk of death, both in all patients and in different subgroups? Is DAA effective in the treatment of patients with severe sepsis and low risk of death? Is DAA cost effective in the treatment of patients with severe sepsis compared to placebo? Methods: Only studies with adult patients are included. There are no other exclusion criteria. A systematic literature search is performed by the German Institute of Medical Documentation and Information (DIMDI. The literature search yielded as a total of 847 hits. After screening of the abstracts, 165 medical and 101 economic publications were chosen for full text appraisal. Results: Therapy with DAA appears to be cost effective in reducing 28-day-mortality in patients with severe sepsis and a high risk of death. A high risk of death is indicated by the presence of multiorgan failure (≥2 and/or an APACHE-II-Score ≥25. Therapy with DAA is not associated with a long-term reduction of mortality at later follow-up assessments. Therapy with DAA is not associated with a long-term reduction of mortality at later follow-up assessments. Therapy with DAA is cost-effective in patients with multiorgan failure and/or an APACHE II Score (≥25. In patients with a lower risk of death, DAA is not cost-effective. Costs associated with bleeding events have been rarely included in cost calculations. Discussion: DAA appears to reduce mortality in patients with severe sepsis and a high

  7. Innate Defense against Influenza A Virus: Activity of Human Neutrophil Defensins and Interactions of Defensins with Surfactant Protein D

    DEFF Research Database (Denmark)

    Hartshorn, Kevan L.; White, Mitchell R.; Tecle, Tesfaldet

    2006-01-01

    Surfactant protein D (SP-D) plays important roles in innate host defense against influenza A virus (IAV) infection, in part by modifying interactions with neutrophils. Human neutrophil defensins (HNPs) inhibit infectivity of enveloped viruses, including IAV. Our goal in this study...

  8. Viral Organization of Human Proteins

    Science.gov (United States)

    Wuchty, Stefan; Siwo, Geoffrey; Ferdig, Michael T.

    2010-01-01

    Although maps of intracellular interactions are increasingly well characterized, little is known about large-scale maps of host-pathogen protein interactions. The investigation of host-pathogen interactions can reveal features of pathogenesis and provide a foundation for the development of drugs and disease prevention strategies. A compilation of experimentally verified interactions between HIV-1 and human proteins and a set of HIV-dependency factors (HDF) allowed insights into the topology and intricate interplay between viral and host proteins on a large scale. We found that targeted and HDF proteins appear predominantly in rich-clubs, groups of human proteins that are strongly intertwined among each other. These assemblies of proteins may serve as an infection gateway, allowing the virus to take control of the human host by reaching protein pathways and diversified cellular functions in a pronounced and focused way. Particular transcription factors and protein kinases facilitate indirect interactions between HDFs and viral proteins. Discerning the entanglement of directly targeted and indirectly interacting proteins may uncover molecular and functional sites that can provide novel perspectives on the progression of HIV infection and highlight new avenues to fight this virus. PMID:20827298

  9. Mammalian target of rapamycin complex 1 activation is required for the stimulation of human skeletal muscle protein synthesis by essential amino acids.

    Science.gov (United States)

    Dickinson, Jared M; Fry, Christopher S; Drummond, Micah J; Gundermann, David M; Walker, Dillon K; Glynn, Erin L; Timmerman, Kyle L; Dhanani, Shaheen; Volpi, Elena; Rasmussen, Blake B

    2011-05-01

    The relationship between mammalian target of rapamycin complex 1 (mTORC1) signaling and muscle protein synthesis during instances of amino acid surplus in humans is based solely on correlational data. Therefore, the goal of this study was to use a mechanistic approach specifically designed to determine whether increased mTORC1 activation is requisite for the stimulation of muscle protein synthesis following L-essential amino acid (EAA) ingestion in humans. Examination of muscle protein synthesis and signaling were performed on vastus lateralis muscle biopsies obtained from 8 young (25 ± 2 y) individuals who were studied prior to and following ingestion of 10 g of EAA during 2 separate trials in a randomized, counterbalanced design. The trials were identical except during 1 trial, participants were administered a single oral dose of a potent mTORC1 inhibitor (rapamycin) prior to EAA ingestion. In response to EAA ingestion, an ~60% increase in muscle protein synthesis was observed during the control trial, concomitant with increased phosphorylation of mTOR (Ser(2448)), ribosomal S6 kinase 1 (Thr(389)), and eukaryotic initiation factor 4E binding protein 1 (Thr(37/46)). In contrast, prior administration of rapamycin completely blocked the increase in muscle protein synthesis and blocked or attenuated activation of mTORC1-signaling proteins. The inhibition of muscle protein synthesis and signaling was not due to differences in either extracellular or intracellular amino acid availability, because these variables were similar between trials. These data support a fundamental role for mTORC1 activation as a key regulator of human muscle protein synthesis in response to increased EAA availability. This information will be useful in the development of evidence-based nutritional therapies targeting mTORC1 to counteract muscle wasting associated with numerous clinical conditions.

  10. Pharmacological Activation of Protein Phosphatase 2 A (PP2A): A Novel Strategy to Fight Against Human Malignancies?

    Science.gov (United States)

    Carratù, Maria Rosaria; Signorile, Anna; De Rasmo, Domenico; Reale, Antonia; Vacca, Angelo

    2016-01-01

    The serine-threonine protein phosphatase 2A (PP2A) regulates multiple cell signaling cascades and its inactivation by viral oncoproteins, mutation of specific structural subunits or upregulation of the cellular endogenous inhibitors may contribute to malignant transformation by regulating specific phosphorylation events. Pharmacological modulation of PP2A activity is becoming an attractive strategy for cancer treatment. Some compounds targeting PP2A are able to induce PP2A reactivation and subsequent cell death in several types of cancer. We undertook a search of bibliographic databases for peer-reviewed articles focusing on the main item of the review. We selected articles published in indexed journals. The quality of retrieved papers was appraised using the standard bibliometric indicators. One hundred and fourteen papers were included in the review. Twenty-seven papers gave an overview of structure and physiological role of PP2A. Twenty-five papers outlined the role of PP2A in tumor suppression. Forty papers analyzed the mechanism involved in PP2A reactivation by synthetic compounds, and twenty-two papers outlined the capability of natural compounds of restoring PP2A activity and how this could be beneficial. Findings analyzed in this review underline the central role of PP2A as a regulator of cell growth and survival, hence its function as tumor suppressor. The discovery that some compounds, either synthetic or natural, are capable of reactivating PP2A opens up new perspectives for future strategies to fully exploit therapeutic potential in human cancer. Thus, this review could also be of particular interest to pharmaceutical or biotechnology companies for drug design and targeted delivery.

  11. Elevated NF-κB activation is conserved in human myocytes cultured from obese type 2 diabetic patients and attenuated by AMP-activated protein kinase

    DEFF Research Database (Denmark)

    Green, Charlotte Jane; Pedersen, Maria; Pedersen, Bente K

    2011-01-01

    To examine whether the inflammatory phenotype found in obese and diabetic individuals is preserved in isolated, cultured myocytes and to assess the effectiveness of pharmacological AMP-activated protein kinase (AMPK) activation upon the attenuation of inflammation in these myocytes....

  12. Angiotensin I-Converting Enzyme (ACE Inhibitory Activity and ACE Inhibitory Peptides of Salmon (Salmo salar Protein Hydrolysates Obtained by Human and Porcine Gastrointestinal Enzymes

    Directory of Open Access Journals (Sweden)

    Małgorzata Darewicz

    2014-08-01

    Full Text Available The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes and ex vivo digestion (with human gastrointestinal enzymes. Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50% of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes.

  13. Potent antitumor activities of recombinant human PDCD5 protein in combination with chemotherapy drugs in K562 cells

    International Nuclear Information System (INIS)

    Shi, Lin; Song, Quansheng; Zhang, Yingmei; Lou, Yaxin; Wang, Yanfang; Tian, Linjie; Zheng, Yi; Ma, Dalong; Ke, Xiaoyan; Wang, Ying

    2010-01-01

    Conventional chemotherapy is still frequently used. Programmed cell death 5 (PDCD5) enhances apoptosis of various tumor cells triggered by certain stimuli and is lowly expressed in leukemic cells from chronic myelogenous leukemia patients. Here, we describe for the first time that recombinant human PDCD5 protein (rhPDCD5) in combination with chemotherapy drugs has potent antitumor effects on chronic myelogenous leukemia K562 cells in vitro and in vivo. The antitumor efficacy of rhPDCD5 protein with chemotherapy drugs, idarubicin (IDR) or cytarabine (Ara-C), was examined in K562 cells in vitro and K562 xenograft tumor models in vivo. rhPDCD5 protein markedly increased the apoptosis rates and decreased the colony-forming capability of K562 cells after the combined treatment with IDR or Ara-C. rhPDCD5 protein by intraperitoneal administration dramatically improved the antitumor effects of IDR treatment in the K562 xenograft model. The tumor sizes and cell proliferation were significantly decreased; and TUNEL positive cells were significantly increased in the combined group with rhPDCD5 protein and IDR treatment compared with single IDR treatment groups. rhPDCD5 protein, in combination with IDR, has potent antitumor effects on chronic myelogenous leukemia K562 cells and may be a novel and promising agent for the treatment of chronic myelogenous leukemia.

  14. Human Antimicrobial Peptides and Proteins

    Directory of Open Access Journals (Sweden)

    Guangshun Wang

    2014-05-01

    Full Text Available As the key components of innate immunity, human host defense antimicrobial peptides and proteins (AMPs play a critical role in warding off invading microbial pathogens. In addition, AMPs can possess other biological functions such as apoptosis, wound healing, and immune modulation. This article provides an overview on the identification, activity, 3D structure, and mechanism of action of human AMPs selected from the antimicrobial peptide database. Over 100 such peptides have been identified from a variety of tissues and epithelial surfaces, including skin, eyes, ears, mouths, gut, immune, nervous and urinary systems. These peptides vary from 10 to 150 amino acids with a net charge between −3 and +20 and a hydrophobic content below 60%. The sequence diversity enables human AMPs to adopt various 3D structures and to attack pathogens by different mechanisms. While α-defensin HD-6 can self-assemble on the bacterial surface into nanonets to entangle bacteria, both HNP-1 and β-defensin hBD-3 are able to block cell wall biosynthesis by binding to lipid II. Lysozyme is well-characterized to cleave bacterial cell wall polysaccharides but can also kill bacteria by a non-catalytic mechanism. The two hydrophobic domains in the long amphipathic α-helix of human cathelicidin LL-37 lays the basis for binding and disrupting the curved anionic bacterial membrane surfaces by forming pores or via the carpet model. Furthermore, dermcidin may serve as ion channel by forming a long helix-bundle structure. In addition, the C-type lectin RegIIIα can initially recognize bacterial peptidoglycans followed by pore formation in the membrane. Finally, histatin 5 and GAPDH(2-32 can enter microbial cells to exert their effects. It appears that granulysin enters cells and kills intracellular pathogens with the aid of pore-forming perforin. This arsenal of human defense proteins not only keeps us healthy but also inspires the development of a new generation of personalized

  15. Human conglutinin-like protein

    DEFF Research Database (Denmark)

    Jensenius, J C; Thiel, S; Baatrup, G

    1985-01-01

    The presence in human plasma of a molecule homologous to bovine conglutinin is indicated by the results of biological and immunochemical analysis. The human conglutinin-like protein shows calcium-dependent binding to complement-treated solid phase IgG and immunological cross-reaction with chicken...... anti-bovine conglutinin. The binding of the human protein to complement-treated IgG was inhibited by N-acetyl-D-glucosamine but not by other sugars. Analysis by SDS-PAGE and Western blotting showed reaction of anti-conglutinin with molecules of similar mobility to the monomer and hexamer of bovine...

  16. Human Mediator Enhances Activator-Facilitated Recruitment of RNA Polymerase II and Promoter Recognition by TATA-Binding Protein (TBP) Independently of TBP-Associated Factors

    OpenAIRE

    Wu, Shwu-Yuan; Zhou, Tianyuan; Chiang, Cheng-Ming

    2003-01-01

    Mediator is a general cofactor implicated in the functions of many transcriptional activators. Although Mediator with different protein compositions has been isolated, it remains unclear how Mediator facilitates activator-dependent transcription, independent of its general stimulation of basal transcription. To define the mechanisms of Mediator function, we isolated two forms of human Mediator complexes (Mediator-P.5 and Mediator-P.85) and demonstrated that Mediator-P.5 clearly functions by e...

  17. Body weight management effect of burdock (Arctium lappa L.) root is associated with the activation of AMP-activated protein kinase in human HepG2 cells.

    Science.gov (United States)

    Kuo, Daih-Huang; Hung, Ming-Chi; Hung, Chao-Ming; Liu, Li-Min; Chen, Fu-An; Shieh, Po-Chuen; Ho, Chi-Tang; Way, Tzong-Der

    2012-10-01

    Burdock (Arcticum lappa L.) root is used in folk medicine and also as a vegetable in Asian countries. In the present study, burdock root treatment significantly reduced body weight in rats. To evaluate the bioactive compounds, we successively extracted the burdock root with ethanol (AL-1), and fractionated it with n-hexane (AL-2), ethyl acetate (AL-3), n-butanol (AL-4), and water (AL-5). Among these fractions, AL-2 contained components with the most effective hypolipidemic potential in human hepatoma HepG2 cells. AL-2 decreased the expression of fatty acid synthase (FASN) and inhibited the activity of acetyl-coenzyme A carboxylase (ACC) by stimulating AMP-activated protein kinase (AMPK) through the LKB1 pathway. Three active compounds were identified from the AL-2, namely α-linolenic acid, methyl α-linolenate, and methyl oleate. These results suggest that burdock root is expected to be useful for body weight management. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Proteins aggregation and human diseases

    Science.gov (United States)

    Hu, Chin-Kun

    2015-04-01

    Many human diseases and the death of most supercentenarians are related to protein aggregation. Neurodegenerative diseases include Alzheimer's disease (AD), Huntington's disease (HD), Parkinson's disease (PD), frontotemporallobar degeneration, etc. Such diseases are due to progressive loss of structure or function of neurons caused by protein aggregation. For example, AD is considered to be related to aggregation of Aβ40 (peptide with 40 amino acids) and Aβ42 (peptide with 42 amino acids) and HD is considered to be related to aggregation of polyQ (polyglutamine) peptides. In this paper, we briefly review our recent discovery of key factors for protein aggregation. We used a lattice model to study the aggregation rates of proteins and found that the probability for a protein sequence to appear in the conformation of the aggregated state can be used to determine the temperature at which proteins can aggregate most quickly. We used molecular dynamics and simple models of polymer chains to study relaxation and aggregation of proteins under various conditions and found that when the bending-angle dependent and torsion-angle dependent interactions are zero or very small, then protein chains tend to aggregate at lower temperatures. All atom models were used to identify a key peptide chain for the aggregation of insulin chains and to find that two polyQ chains prefer anti-parallel conformation. It is pointed out that in many cases, protein aggregation does not result from protein mis-folding. A potential drug from Chinese medicine was found for Alzheimer's disease.

  19. ZNF322, a novel human C2H2 Krueppel-like zinc-finger protein, regulates transcriptional activation in MAPK signaling pathways

    International Nuclear Information System (INIS)

    Li Yongqing; Wang Yuequn; Zhang Caibo; Yuan Wuzhou; Wang Jun; Zhu Chuanbing; Chen Lei; Huang Wen; Zeng Weiqi; Wu Xiushan; Liu Mingyao

    2004-01-01

    Cardiac differentiation involves a cascade of coordinated gene expression that regulates cell proliferation and matrix protein formation in a defined temporal-spatial manner. The C 2 H 2 zinc finger-containing transcription factors have been implicated as critical regulators of multiple cardiac-expressed genes and are important for human heart development and diseases. Here we have identified and characterized a novel zinc-finger gene named ZNF322 using degenerated primers from a human embryo heart cDNA library. The gene contains four exons and spans 23.2 kb in chromosome 6p22.1 region, and transcribes a 2.7 kb mRNA that encodes a protein with 402 amino acid residues. The predicted protein contains 9 tandem C 2 H 2 -type zinc-finger motifs. Northern blot analysis shows that ZNF322 is expressed in every human tissue examined at adult stage and during embryonic developmental stages from 80 days to 24 weeks. When overexpressed in COS-7 cells, ZNF322-EGFP fusion protein is detected in the nucleus and cytoplasm. Reporter gene assays show that ZNF322 is a transcriptional activator. Furthermore, overexpression of ZNF322 in COS-7 cells activates the transcriptional activity of SRE and AP-1. Together, these results suggest that ZNF322 is a member of the zinc-finger transcription factor family and may act as a positive regulator in gene transcription mediated by the MAPK signaling pathways

  20. Phosphorylation of protein kinase C sites Ser42/44 decreases Ca2+-sensitivity and blunts enhanced length-dependent activation in response to protein kinase A in human cardiomyocytes

    NARCIS (Netherlands)

    Wijnker, P.J.M.; Sequeira Oliveira, V.; Witjas-Paalberends, E.R.; Foster, D.B.; dos Remedios, C.G.; Murphy, A.M.; Stienen, G.J.M.; van der Velden, J.

    2014-01-01

    Protein kinase C (PKC)-mediated phosphorylation of troponin I (cTnI) at Ser42/44 is increased in heart failure. While studies in rodents demonstrated that PKC-mediated Ser42/44 phosphorylation decreases maximal force and ATPase activity, PKC incubation of human cardiomyocytes did not affect maximal

  1. Protein Crystal Recombinant Human Insulin

    Science.gov (United States)

    1994-01-01

    The comparison of protein crystal, Recombiant Human Insulin; space-grown (left) and earth-grown (right). On STS-60, Spacehab II indicated that space-grown crystals are larger and of greater optical clarity than their earth-grown counterparts. Recombiant Human Insulin facilitates the incorporation of glucose into cells. In diabetics, there is either a decrease in or complete lack of insulin, thereby leading to several harmful complications. Principal Investigator is Larry DeLucas.

  2. Defense Human Resources Activity > PERSEREC

    Science.gov (United States)

    Skip to main content (Press Enter). Toggle navigation Defense Human Resources Activity Search Search Defense Human Resources Activity: Search Search Defense Human Resources Activity: Search Defense Human Resources Activity U.S. Department of Defense Defense Human Resources Activity Overview

  3. Aspirin and salicylate bind to immunoglobulin heavy chain binding protein (BiP) and inhibit its ATPase activity in human fibroblasts.

    Science.gov (United States)

    Deng, W G; Ruan, K H; Du, M; Saunders, M A; Wu, K K

    2001-11-01

    Salicylic acid (SA), an endogenous signaling molecule of plants, possesses anti-inflammatory and anti-neoplastic actions in human. Its derivative, aspirin, is the most commonly used anti-inflammatory and analgesic drug. Aspirin and sodium salicylate (salicylates) have been reported to have multiple pharmacological actions. However, it is unclear whether they bind to a cellular protein. Here, we report for the first time the purification from human fibroblasts of a approximately 78 kDa salicylate binding protein with sequence identity to immunoglobulin heavy chain binding protein (BiP). The Kd values of SA binding to crude extract and to recombinant BiP were 45.2 and 54.6 microM, respectively. BiP is a chaperone protein containing a polypeptide binding site recognizing specific heptapeptide sequence and an ATP binding site. A heptapeptide with the specific sequence displaced SA binding in a concentration-dependent manner whereas a control heptapeptide did not. Salicylates inhibited ATPase activity stimulated by this specific heptapeptide but did not block ATP binding or induce BiP expression. These results indicate that salicylates bind specifically to the polypeptide binding site of BiP in human cells that may interfere with folding and transport of proteins important in inflammation.

  4. Baculoviral expression and characterization of human recombinant PGCP in the form of an active mature dimer and an inactive precursor protein.

    Science.gov (United States)

    Zajc, Tajana; Suban, Dejan; Rajković, Jelena; Dolenc, Iztok

    2011-02-01

    The human-blood plasma glutamate carboxypeptidase (PGCP) is a proteinase that acts on the unsubstituted N- and C-termini of dipeptides. It has been suggested that this PGCP is involved in the release of thyroxine. Furthermore, research has suggested that its activity is up-regulated in hepatitis-C-virus-infected patients with hepatocellular carcinoma. In this study expressed human PGCP in the baculovirus expression system was produced by a Sf9 insect cell line with aim to prepare sufficient amounts of active recombinant enzyme for a subsequent biological characterization. Recombinant PGCP was expressed and secreted into the medium in the form of an inactive proenzyme. It was gradually converted into an active form in the medium after three days, with the highest expression of the active form on day six. The protein was sequentially purified by a combination of various liquid chromatographies, such as hydroxyapatite, ion exchange, and gel chromatography, and as final step with affinity chromatography on Phe-Leu-Sepharose. The human PGCP was purified as an active enzyme in the dimer form and as inactive precursor protein. The dipeptidase activity was confirmed by measuring the hydrolysis of the Ser-Met dipeptide at a slightly acidic pH. Copyright © 2010 Elsevier Inc. All rights reserved.

  5. Human interleukin 1. beta. stimulates islet insulin release by a mechanism not dependent on changes in phospholipase C and protein kinase C activities or Ca sup 2+ handling

    Energy Technology Data Exchange (ETDEWEB)

    Welsh, N.; Nilsson, T.; Hallberg, A.; Arkhammar, P.; Berggren, P.-O.; Sandler, S.

    1989-01-01

    Isolated islets from adult rats or obese hyperglycemic (ob/ob) mice were incubated with human recombinant interleukin 1{beta} in order to study whether the acute effects of the cytokine on islet insulin release are associated with changes in islet phospholipase C activity, Ca{sup 2+} handling or protein phosphorylation. The cytokine stimulated insulin release both at low and high glucose concentrations during one hour incubations. In shortterm incubations (<1 min) interleukin 1{beta} did not affect the production of inositoltrisphosphate. Addition of interleukin 1{beta} affected neither the cytoplasmic free Ca{sup 2+} concentration at rest nor that observed subsequent to stimulation with a high concentration of glucose. Furthermore, the endogenous protein kinase C activity, as visualized by immunoprecipitation of a {sup 32}P-labelled substrate for this enzyme, was not altered by interleukin 1{beta}. Separation of {sup 32}P-labelled proteins by means of 2-dimensional gel electrophoresis failed to reveal any specific effects of the cytokine on the total protein phosphorylation activity. These results suggest that the stimulatory effects on insulin release exerted by interleukin 1{beta} are not caused by acute activation of phospholipase C and protein kinase C or by an alternation of islet Ca{sup 2+} handling of the B-cells. (author).

  6. Human interleukin 1β stimulates islet insulin release by a mechanism not dependent on changes in phospholipase C and protein kinase C activities or Ca2+ handling

    International Nuclear Information System (INIS)

    Welsh, N.; Nilsson, T.; Hallberg, A.; Arkhammar, P.; Berggren, P.-O.; Sandler, S.

    1989-01-01

    Isolated islets from adult rats or obese hyperglycemic (ob/ob) mice were incubated with human recombinant interleukin 1β in order to study whether the acute effects of the cytokine on islet insulin release are associated with changes in islet phospholipase C activity, Ca 2+ handling or protein phosphorylation. The cytokine stimulated insulin release both at low and high glucose concentrations during one hour incubations. In shortterm incubations ( 2+ concentration at rest nor that observed subsequent to stimulation with a high concentration of glucose. Furthermore, the endogenous protein kinase C activity, as visualized by immunoprecipitation of a 32 P-labelled substrate for this enzyme, was not altered by interleukin 1β. Separation of 32 P-labelled proteins by means of 2-dimensional gel electrophoresis failed to reveal any specific effects of the cytokine on the total protein phosphorylation activity. These results suggest that the stimulatory effects on insulin release exerted by interleukin 1β are not caused by acute activation of phospholipase C and protein kinase C or by an alternation of islet Ca 2+ handling of the B-cells. (author)

  7. Cellular inhibitor of apoptosis protein 2 (cIAP2) controls human colonic epithelial restitution, migration and Rac1 activation

    DEFF Research Database (Denmark)

    Seidelin, JB; Larsen, Sylvester; Linnemann, D

    2015-01-01

    epithelial cells (IECs) was increased at the wound edge after 24 h (P 2 was induced in vitro in regenerating Caco2 IECs after wound infliction (P ...Identification of pathways involved in wound healing is important for understanding the pathogenesis of various intestinal diseases. Cellular inhibitor of apoptosis protein 2 (cIAP2) regulates proliferation and migration in nonepithelial cells and is expressed in human colonocytes. The aim...... of the study was to investigate the role of cIAP2 for wound healing in the normal human colon. Wound tissue was generated by taking rectosigmoidal biopsies across an experimental ulcer in healthy subjects after 5, 24, and 48 h. In experimental ulcers, the expression of cIAP2 in regenerating intestinal...

  8. Structural analysis of recombinant human protein QM

    International Nuclear Information System (INIS)

    Gualberto, D.C.H.; Fernandes, J.L.; Silva, F.S.; Saraiva, K.W.; Affonso, R.; Pereira, L.M.; Silva, I.D.C.G.

    2012-01-01

    Full text: The ribosomal protein QM belongs to a family of ribosomal proteins, which is highly conserved from yeast to humans. The presence of the QM protein is necessary for joining the 60S and 40S subunits in a late step of the initiation of mRNA translation. Although the exact extra-ribosomal functions of QM are not yet fully understood, it has been identified as a putative tumor suppressor. This protein was reported to interact with the transcription factor c-Jun and thereby prevent c-Jun actives genes of the cellular growth. In this study, the human QM protein was expressed in bacterial system, in the soluble form and this structure was analyzed by Circular Dichroism and Fluorescence. The results of Circular Dichroism showed that this protein has less alpha helix than beta sheet, as described in the literature. QM protein does not contain a leucine zipper region; however the ion zinc is necessary for binding of QM to c-Jun. Then we analyzed the relationship between the removal of zinc ions and folding of protein. Preliminary results obtained by the technique Fluorescence showed a gradual increase in fluorescence with the addition of increasing concentration of EDTA. This suggests that the zinc is important in the tertiary structure of the protein. More studies are being made for better understand these results. (author)

  9. Characterization of the single transmembrane domain of human receptor activity-modifying protein 3 in adrenomedullin receptor internalization

    International Nuclear Information System (INIS)

    Kuwasako, Kenji; Kitamura, Kazuo; Nagata, Sayaka; Nozaki, Naomi; Kato, Johji

    2012-01-01

    Highlights: ► RAMP3 mediates CLR internalization much less effectively than does RAMP2. ► The RAMP3 TMD participates in the negative regulation of CLR/RAMP3 internalization. ► A new strategy of promoting internalization and resensitization of the receptor was found. -- Abstract: Two receptor activity-modifying proteins (RAMP2 and RAMP3) enable calcitonin receptor-like receptor (CLR) to function as two heterodimeric receptors (CLR/RAMP2 and CLR/RAMP3) for adrenomedullin (AM), a potent cardiovascular protective peptide. Following AM stimulation, both receptors undergo rapid internalization through a clathrin-dependent pathway, after which CLR/RAMP3, but not CLR/RAMP2, can be recycled to the cell surface for resensitization. However, human (h)RAMP3 mediates CLR internalization much less efficiently than does hRAMP2. Therefore, the molecular basis of the single transmembrane domain (TMD) and the intracellular domain of hRAMP3 during AM receptor internalization was investigated by transiently transfecting various RAMP chimeras and mutants into HEK-293 cells stably expressing hCLR. Flow cytometric analysis revealed that substituting the RAMP3 TMD with that of RAMP2 markedly enhanced AM-induced internalization of CLR. However, this replacement did not enhance the cell surface expression of CLR, [ 125 I]AM binding affinity or AM-induced cAMP response. More detailed analyses showed that substituting the Thr 130 –Val 131 sequence in the RAMP3 TMD with the corresponding sequence (Ile 157 –Pro 158 ) from RAMP2 significantly enhanced AM-mediated CLR internalization. In contrast, substituting the RAMP3 target sequence with Ala 130 –Ala 131 did not significantly affect CLR internalization. Thus, the RAMP3 TMD participates in the negative regulation of CLR/RAMP3 internalization, and the aforementioned introduction of the Ile–Pro sequence into the RAMP3 TMD may be a strategy for promoting receptor internalization/resensitization.

  10. Assessment of the distribution of protein in the human body by in-vivo neutron activation analysis

    International Nuclear Information System (INIS)

    Burkinshaw, L.; Hill, G.L.; Morgan, D.B.

    1979-01-01

    Whole-body in-vivo neutron activation analysis has been developed into a clinically acceptable technique for measuring total-body nitrogen. Since most of the nitrogen is in protein, the result gives an estimates of total-body protein, and this has proved very informative in studies of nutritional problems. It would often be useful to know how the total protein is divided between muscle and other lean tissues, and this could be determined if the body content of some other substance, distributed differently between the two types of tissue, were known. Potassium is a suitable substance. The total amount in the body is always measured in the course of the activation analysis procedure, and its concentration relative to nitrogen is more than twice as high in muscle as it is in the other lean tissues. Therefore a high proportion of muscle in the body will be reflected in a high ratio of total-body potassium to total-body nitrogen. Starting with this observation, a mathematical model has been developed which makes it possible to estimate the masses and protein contents of muscle and non-muscle lean tissues from total-body nitrogen and potassium. The errors of estimation are too large to allow conclusions to be drawn from a single measurement of an individual, but they do permit mean values for groups of subjects to be compared. This way of interpreting the results of in-vivo neutron activation analysis is expected to increase the value of the technique for studying nutritional problems. (author)

  11. Proteins aggregation and human diseases

    International Nuclear Information System (INIS)

    Hu, Chin-Kun

    2015-01-01

    Many human diseases and the death of most supercentenarians are related to protein aggregation. Neurodegenerative diseases include Alzheimer's disease (AD), Huntington's disease (HD), Parkinson's disease (PD), frontotemporallobar degeneration, etc. Such diseases are due to progressive loss of structure or function of neurons caused by protein aggregation. For example, AD is considered to be related to aggregation of Aβ40 (peptide with 40 amino acids) and Aβ42 (peptide with 42 amino acids) and HD is considered to be related to aggregation of polyQ (polyglutamine) peptides. In this paper, we briefly review our recent discovery of key factors for protein aggregation. We used a lattice model to study the aggregation rates of proteins and found that the probability for a protein sequence to appear in the conformation of the aggregated state can be used to determine the temperature at which proteins can aggregate most quickly. We used molecular dynamics and simple models of polymer chains to study relaxation and aggregation of proteins under various conditions and found that when the bending-angle dependent and torsion-angle dependent interactions are zero or very small, then protein chains tend to aggregate at lower temperatures. All atom models were used to identify a key peptide chain for the aggregation of insulin chains and to find that two polyQ chains prefer anti-parallel conformation. It is pointed out that in many cases, protein aggregation does not result from protein mis-folding. A potential drug from Chinese medicine was found for Alzheimer's disease. (paper)

  12. Involvement of p38 mitogen-activated protein kinase in acquired gemcitabine-resistant human urothelial carcinoma sublines

    Directory of Open Access Journals (Sweden)

    Yu-Ting Kao

    2014-07-01

    Full Text Available Resistance to chemotherapeutic drugs is one of the major challenges in the treatment of cancer. A better understanding of how resistance arises and what molecular alterations correlate with resistance is the key to developing novel effective therapeutic strategies. To investigate the underlying mechanisms of gemcitabine (Gem resistance and provide possible therapeutic options, three Gem-resistant urothelial carcinoma sublines were established (NG0.6, NG0.8, and NG1.0. These cells were cross-resistant to arabinofuranosyl cytidine and cisplatin, but sensitive to 5-fluorouracil. The resistant cells expressed lower values of [hENT1 × dCK/RRM1 × RRM2] mRNA ratio. Two adenosine triphosphate-binding cassette proteins ABCD1 as well as multidrug resistance protein 1 were elevated. Moreover, cyclin D1, cyclin-dependent kinases 2 and 4 were upregulated, whereas extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase (MAPK activity were repressed significantly. Administration of p38 MAPK inhibitor significantly reduced the Gem sensitivity in NTUB1 cells, whereas that of an extracellular signal-regulated kinase MAPK inhibitor did not. Furthermore, the Gem-resistant sublines also exhibited higher migration ability. Forced expression of p38 MAPK impaired the cell migration activity and augmented Gem sensitivity in NG1.0 cells. Taken together, these results demonstrate that complex mechanisms were merged in acquiring Gem resistance and provide information that can be important for developing therapeutic targets for treating Gem-resistant tumors.

  13. Requirement of T-lymphokine-activated killer cell-originated protein kinase for TRAIL resistance of human HeLa cervical cancer cells

    International Nuclear Information System (INIS)

    Kwon, Hyeok-Ran; Lee, Ki Won; Dong, Zigang; Lee, Kyung Bok; Oh, Sang-Muk

    2010-01-01

    T-lymphokine-activated killer cell-originated protein kinase (TOPK) appears to be highly expressed in various cancer cells and to play an important role in maintaining proliferation of cancer cells. However, the underlying mechanism by which TOPK regulates growth of cancer cells remains elusive. Here we report that upregulated endogenous TOPK augments resistance of cancer cells to apoptosis induced by tumor necrosis factor-related apoptosis inducing ligand (TRAIL). Stable knocking down of TOPK markedly increased TRAIL-mediated apoptosis of human HeLa cervical cancer cells, as compared with control cells. Caspase 8 or caspase 3 activities in response to TRAIL were greatly incremented in TOPK-depleted cells. Ablation of TOPK negatively regulated TRAIL-mediated NF-κB activity. Furthermore, expression of NF-κB-dependent genes, FLICE-inhibitory protein (FLIP), inhibitor of apoptosis protein 1 (c-IAP1), or X-linked inhibitor of apoptosis protein (XIAP) was reduced in TOPK-depleted cells. Collectively, these findings demonstrated that TOPK contributed to TRAIL resistance of cancer cells via NF-κB activity, suggesting that TOPK might be a potential molecular target for successful cancer therapy using TRAIL.

  14. Effect of hydrophilicity of carbon nanotube arrays on the release rate and activity of recombinant human bone morphogenetic protein-2

    Energy Technology Data Exchange (ETDEWEB)

    Han Zhaojun; Ostrikov, Kostya [Plasma Nanoscience Centre Australia (PNCA), CSIRO Materials Science and Engineering, Lindfield, New South Wales 2070 (Australia); Tan, Cher Ming; Tay, Beng Kang [School of Electrical and Electronic Engineering, Nanyang Technological University, 639798 (Singapore); Peel, Sean A F, E-mail: zhaojun.han@csiro.au [Department of Dentistry, University of Toronto, Toronto, ON, M5G 1G6 (Canada)

    2011-07-22

    Novel nanostructures such as vertically aligned carbon nanotube (CNT) arrays have received increasing interest as drug delivery carriers. In the present study, two CNT arrays with extreme surface wettabilities are fabricated and their effects on the release of recombinant human bone morphogenetic protein-2 (rhBMP-2) are investigated. It is found that the superhydrophilic arrays retained a larger amount of rhBMP-2 than the superhydrophobic ones. Further use of a poloxamer diffusion layer delayed the initial burst and resulted in a greater total amount of rhBMP-2 released from both surfaces. In addition, rhBMP-2 bound to the superhydrophilic CNT arrays remained bioactive while they denatured on the superhydrophobic surfaces. These results are related to the combined effects of rhBMP-2 molecules interacting with poloxamer and the surface, which could be essential in the development of advanced carriers with tailored surface functionalities.

  15. Human plasminogen binding protein tetranectin

    DEFF Research Database (Denmark)

    Kastrup, J S; Rasmussen, H; Nielsen, B B

    1997-01-01

    The recombinant human plasminogen binding protein tetranectin (TN) and the C-type lectin CRD of this protein (TN3) have been crystallized. TN3 crystallizes in the tetragonal space group P4(2)2(1)2 with cell dimensions a = b = 64.0, c = 75.7 A and with one molecule per asymmetric unit. The crystals...... to at least 2.5 A. A full data set has been collected to 3.0 A. The asymmetric unit contains one monomer of TN. Molecular replacement solutions for TN3 and TN have been obtained using the structure of the C-type lectin CRD of rat mannose-binding protein as search model. The rhombohedral space group indicates...

  16. The Duffy binding protein (PkDBPαII) of Plasmodium knowlesi from Peninsular Malaysia and Malaysian Borneo show different binding activity level to human erythrocytes.

    Science.gov (United States)

    Lim, Khai Lone; Amir, Amirah; Lau, Yee Ling; Fong, Mun Yik

    2017-08-11

    The zoonotic Plasmodium knowlesi is a major cause of human malaria in Malaysia. This parasite uses the Duffy binding protein (PkDBPαII) to interact with the Duffy antigen receptor for chemokines (DARC) receptor on human and macaque erythrocytes to initiate invasion. Previous studies on P. knowlesi have reported distinct Peninsular Malaysia and Malaysian Borneo PkDBPαII haplotypes. In the present study, the differential binding activity of these haplotypes with human and macaque (Macaca fascicularis) erythrocytes was investigated. The PkDBPαII of Peninsular Malaysia and Malaysian Borneo were expressed on the surface of COS-7 cells and tested with human and monkey erythrocytes, with and without anti-Fy6 (anti-Duffy) monoclonal antibody treatment. Binding activity level was determined by counting the number of rosettes formed between the transfected COS-7 cells and the erythrocytes. Anti-Fy6 treatment was shown to completely block the binding of human erythrocytes with the transfected COS-7 cells, thus verifying the specific binding of human DARC with PkDBPαII. Interestingly, the PkDBPαII of Peninsular Malaysia displayed a higher binding activity with human erythrocytes when compared with the Malaysian Borneo PkDBPαII haplotype (mean number of rosettes formed = 156.89 ± 6.62 and 46.00 ± 3.57, respectively; P < 0.0001). However, no difference in binding activity level was seen in the binding assay using M. fascicularis erythrocytes. This study is the first report of phenotypic difference between PkDBPαII haplotypes. The biological implication of this finding is yet to be determined. Therefore, further studies need to be carried out to determine whether this differential binding level can be associated with severity of knowlesi malaria in human.

  17. Role of protein kinase C in TBT-induced inhibition of lytic function and MAPK activation in human natural killer cells.

    Science.gov (United States)

    Abraha, Abraham B; Rana, Krupa; Whalen, Margaret M

    2010-11-01

    Human natural killer (NK) cells are lymphocytes that destroy tumor and virally infected cells. Previous studies have shown that exposure of NK cells to tributyltin (TBT) greatly diminishes their ability to destroy tumor cells (lytic function) while activating mitogen-activated protein kinases (MAPK) (p44/42, p38, and JNK) in NK cells. The signaling pathway that regulates NK lytic function appears to include activation of protein kinase C(PKC) as well as MAPK activity. TBT-induced activation of MAPKs would trigger a portion of the NK lytic signaling pathway, which would then leave the NK cell unable to trigger this pathway in response to a subsequent encounter with a target cell. In the present study we evaluated the involvement of PKC in inhibition of NK lysis of tumor cells and activation of MAPKs caused by TBT exposure. TBT caused a 2–3-fold activation of PKC at concentrations ranging from 50 to 300 nM (16–98 ng/ml),indicating that activation of PKC occurs in response to TBT exposure. This would then leave the NK cell unable to respond to targets. Treatment with the PKC inhibitor, bisindolylmaleimide I, caused an 85% decrease in the ability of NK cells to lyse tumor cells, validating the involvement of PKC in the lytic signaling pathway. The role of PKC in the activation of MAPKs by TBT was also investigated using bisindolylmaleimide I. The results indicated that, in NK cells where PKC activation was blocked, there was no activation of the MAPK, p44/42 in response to TBT.However, TBT-induced activation of the MAPKs, p38 and JNK did not require PKC activation. These results indicate the pivotal role of PKC in the TBT-induced loss of NK lytic function including activation of p44/42 by TBT in NK cells.

  18. Role of protein kinase C in the TBT-induced inhibition of lytic function and MAPK activation in human natural killer cells

    Science.gov (United States)

    Abraha, Abraham B.; Rana, Krupa; Whalen, Margaret M.

    2010-01-01

    Human natural killer (NK) cells are lymphocytes that destroy tumor and virally infected cells. Previous studies have shown that exposures of NK cells to tributyltin (TBT) greatly diminish their ability to destroy tumor cells (lytic function) while activating mitogen-activated protein kinases (MAPK) (p44/42, p38, and JNK) in the NK cells. The signaling pathway that regulates NK lytic function appears to include activation of protein kinase C (PKC) as well as MAPK activity. The TBT-induced activation of MAPKs would trigger a portion of the NK lytic signaling pathway, which would then leave the NK cell unable to trigger this pathway in response to a subsequent encounter with a target cell. In the present study we evaluated the involvement of PKC in the inhibition of NK lysis of tumor cells and activation of MAPKs caused by TBT exposures. TBT caused a 2–3 fold activation of PKC at concentrations ranging from 50–300 nM (16–98 ng/mL), indicating that activation of PKC occurs in response to TBT exposures. This would then leave the NK cell unable to respond to targets. Treatment with the PKC inhibitor, bisindolylmaleimide I, caused an 85% decrease in the ability of NK cells to lyse tumor cells validating the involvement of PKC in the lytic signaling pathway. The role of PKC in the activation of MAPKs by TBT was also investigated using bisindolylmaleimide I. The results indicated that in NK cells where PKC activation was blocked there was no activation of the MAPK, p44/42 in response to TBT. However, TBT-induced activation of the MAPKs, p38 and JNK did not require PKC activation. These results indicate the pivotal role of PKC in the TBT-induced loss of NK lytic function including the activation of p44/42 by TBT in NK cells. PMID:20390410

  19. Complement Receptor 3-Mediated Inhibition of Inflammasome Priming by Ras GTPase-Activating Protein During Francisella tularensis Phagocytosis by Human Mononuclear Phagocytes

    Directory of Open Access Journals (Sweden)

    Ky V. Hoang

    2018-03-01

    Full Text Available Francisella tularensis is a remarkably infectious facultative intracellular bacterium of macrophages that causes tularemia. Early evasion of host immune responses contributes to the success of F. tularensis as a pathogen. F. tularensis entry into human monocytes and macrophages is mediated by the major phagocytic receptor, complement receptor 3 (CR3, CD11b/CD18. We recently determined that despite a significant increase in macrophage uptake following C3 opsonization of the virulent Type A F. tularensis spp. tularensis Schu S4, this phagocytic pathway results in limited pro-inflammatory cytokine production. Notably, MAP kinase/ERK activation is suppressed immediately during C3-opsonized Schu S4-CR3 phagocytosis. A mathematical model of CR3-TLR2 crosstalk predicted early involvement of Ras GTPase-activating protein (RasGAP in immune suppression by CR3. Here, we link CR3-mediated uptake of opsonized Schu S4 by human monocytes and macrophages with inhibition of early signal 1 inflammasome activation, evidenced by limited caspase-1 cleavage and IL-18 release. This inhibition is due to increased RasGAP activity, leading to a reduction in the Ras-ERK signaling cascade upstream of the early inflammasome activation event. Thus, our data uncover a novel signaling pathway mediated by CR3 following engagement of opsonized virulent F. tularensis to limit inflammasome activation in human phagocytic cells, thereby contributing to evasion of the host innate immune system.

  20. Proteomics reveal energy metabolism and mitogen-activated protein kinase signal transduction perturbation in human Borna disease virus Hu-H1-infected oligodendroglial cells.

    Science.gov (United States)

    Liu, X; Yang, Y; Zhao, M; Bode, L; Zhang, L; Pan, J; Lv, L; Zhan, Y; Liu, S; Zhang, L; Wang, X; Huang, R; Zhou, J; Xie, P

    2014-05-30

    Borna disease virus (BDV) is a neurotropic, non-cytolytic RNA virus which replicates in the cell nucleus targeting mainly hippocampal neurons, but also astroglial and oligodendroglial cells in the brain. BDV is associated with a large spectrum of neuropsychiatric pathologies in animals. Its relationship to human neuropsychiatric illness still remains controversial. We could recently demonstrate that human BDV strain Hu-H1 promoted apoptosis and inhibited cell proliferation in a human oligodendroglial cell line (OL cells) whereas laboratory BDV strain V acted contrariwise. Here, differential protein expression between BDV Hu-H1-infected OL cells and non-infected OL cells was assessed through a proteomics approach, using two-dimensional electrophoresis followed by matrix-assisted laser desorption ionization-time of flight tandem mass spectrometry. A total of 63 differential host proteins were identified in BDV Hu-H1-infected OL cells compared to non-infected OL cells. We found that most changes referred to alterations related to the pentose phosphate pathway, glyoxylate and dicarboxylate metabolism, the tricarboxylic acid (TCA) cycle, and glycolysis /gluconeogenesis. By manual querying, two differential proteins were found to be associated with mitogen-activated protein kinase (MAPK) signal transduction. Five key signaling proteins of this pathway (i.e., p-Raf, p-MEK, p-ERK1/2, p-RSK, and p-MSK) were selected for Western blotting validation. p-ERK1/2 and p-RSK were found to be significantly up-regulated, and p-MSK was found to be significantly down-regulated in BDV Hu-H1-infected OL cells compared to non-infected OL cell. Although BDV Hu-H1 constitutively activated the ERK-RSK pathway, host cell proliferation and nuclear translocation of activated pERK in BDV Hu-H1-infected OL cells were impaired. These findings indicate that BDV Hu-H1 infection of human oligodendroglial cells significantly perturbs host energy metabolism, activates the downstream ERK-RSK complex of

  1. Human NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome activity is regulated by and potentially targetable through Bruton tyrosine kinase.

    Science.gov (United States)

    Liu, Xiao; Pichulik, Tica; Wolz, Olaf-Oliver; Dang, Truong-Minh; Stutz, Andrea; Dillen, Carly; Delmiro Garcia, Magno; Kraus, Helene; Dickhöfer, Sabine; Daiber, Ellen; Münzenmayer, Lisa; Wahl, Silke; Rieber, Nikolaus; Kümmerle-Deschner, Jasmin; Yazdi, Amir; Franz-Wachtel, Mirita; Macek, Boris; Radsak, Markus; Vogel, Sebastian; Schulte, Berit; Walz, Juliane Sarah; Hartl, Dominik; Latz, Eicke; Stilgenbauer, Stephan; Grimbacher, Bodo; Miller, Lloyd; Brunner, Cornelia; Wolz, Christiane; Weber, Alexander N R

    2017-10-01

    The Nod-like receptor NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) and Bruton tyrosine kinase (BTK) are protagonists in innate and adaptive immunity, respectively. NLRP3 senses exogenous and endogenous insults, leading to inflammasome activation, which occurs spontaneously in patients with Muckle-Wells syndrome; BTK mutations cause the genetic immunodeficiency X-linked agammaglobulinemia (XLA). However, to date, few proteins that regulate NLRP3 inflammasome activity in human primary immune cells have been identified, and clinically promising pharmacologic targeting strategies remain elusive. We sought to identify novel regulators of the NLRP3 inflammasome in human cells with a view to exploring interference with inflammasome activity at the level of such regulators. After proteome-wide phosphoproteomics, the identified novel regulator BTK was studied in human and murine cells by using pharmacologic and genetic BTK ablation. Here we show that BTK is a critical regulator of NLRP3 inflammasome activation: pharmacologic (using the US Food and Drug Administration-approved inhibitor ibrutinib) and genetic (in patients with XLA and Btk knockout mice) BTK ablation in primary immune cells led to reduced IL-1β processing and secretion in response to nigericin and the Staphylococcus aureus toxin leukocidin AB (LukAB). BTK affected apoptosis-associated speck-like protein containing a CARD (ASC) speck formation and caspase-1 cleavage and interacted with NLRP3 and ASC. S aureus infection control in vivo and IL-1β release from cells of patients with Muckle-Wells syndrome were impaired by ibrutinib. Notably, IL-1β processing and release from immune cells isolated from patients with cancer receiving ibrutinib therapy were reduced. Our data suggest that XLA might result in part from genetic inflammasome deficiency and that NLRP3 inflammasome-linked inflammation could potentially be targeted pharmacologically through BTK. Copyright © 2017 American Academy of Allergy

  2. Trans-activation of the JC virus late promoter by the tat protein of type 1 human immunodeficiency virus in glial cells

    International Nuclear Information System (INIS)

    Tada, Hiroomi; Lashgari, M.; Amini, S.; Khalili, K.; Rappaport, J.; Wong-Staal, F.

    1990-01-01

    Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system caused by the JC virus (JCV), a human papovavirus. PML is a relatively rare disease seen predominantly in immunocompromised individuals and is a frequent complication observed in AIDS patients. The significantly higher incidence of PML in AIDS patients than in other immunosuppressive disorders has suggested that the presence of human immunodeficiency virus type 1 (HIV-1) in the brain may directly or indirectly contribute to the pathogenesis of this disease. In the present study the authors have examined the expression of the JCV genome in both glial and non-glial cells in the presence of HIV-1 regulatory proteins. They find that the HIV-1-encoded trans-regulatory protein tat increases the basal activity of the JCV late promoter, JCV L , in glial cells. They conclude that the presence of the HIV-1-encoded tat protein may positively affect the JCV lytic cycle in glial cells by stimulating JCV gene expression. The results suggest a mechanism for the relatively high incidence of PML in AIDS patients than in other immunosuppressive disorders. Furthermore, the findings indicate that the HIV-1 regulatory protein tat may stimulate other viral and perhaps cellular promoters, in addition to its own

  3. Involvement of mitogen-activated protein kinases and NFκB in LPS-induced CD40 expression on human monocytic cells

    International Nuclear Information System (INIS)

    Wu Weidong; Alexis, Neil E.; Chen Xian; Bromberg, Philip A.; Peden, David B.

    2008-01-01

    CD40 is a costimulatory molecule linking innate and adaptive immune responses to bacterial stimuli, as well as a critical regulator of functions of other costimulatory molecules. The mechanisms regulating lipopolysaccharide (LPS)-induced CD40 expression have not been adequately characterized in human monocytic cells. In this study we used a human monocytic cell line, THP-1, to investigate the possible mechanisms of CD40 expression following LPS exposure. Exposure to LPS resulted in a dose- and time-dependent increase in CD40 expression. Further studies using immunoblotting and pharmacological inhibitors revealed that mitogen-activated protein kinases (MAPKs) and NFκB were activated by LPS exposure and involved in LPS-induced CD40 expression. Activation of MAPKs was not responsible for LPS-induced NFκB activation. TLR4 was expressed on THP-1 cells and pretreatment of cells with a Toll-like receptor 4 (TLR4) neutralizing antibody (HTA125) significantly blunted LPS-induced MAPK and NFκB activation and ensuing CD40 expression. Additional studies with murine macrophages expressing wild type and mutated TLR4 showed that TLR4 was implicated in LPS-induced ERK and NFκB activation, and CD40 expression. Moreover, blockage of MAPK and NFκB activation inhibited LPS-induced TLR4 expression. In summary, LPS-induced CD40 expression in monocytic cells involves MAPKs and NFκB

  4. Enterovirus 71 VP1 activates calmodulin-dependent protein kinase II and results in the rearrangement of vimentin in human astrocyte cells.

    Directory of Open Access Journals (Sweden)

    Cong Haolong

    Full Text Available Enterovirus 71 (EV71 is one of the main causative agents of foot, hand and mouth disease. Its infection usually causes severe central nervous system diseases and complications in infected infants and young children. In the present study, we demonstrated that EV71 infection caused the rearrangement of vimentin in human astrocytoma cells. The rearranged vimentin, together with various EV71 components, formed aggresomes-like structures in the perinuclear region. Electron microscopy and viral RNA labeling indicated that the aggresomes were virus replication sites since most of the EV71 particles and the newly synthesized viral RNA were concentrated here. Further analysis revealed that the vimentin in the virus factories was serine-82 phosphorylated. More importantly, EV71 VP1 protein is responsible for the activation of calmodulin-dependent protein kinase II (CaMK-II which phosphorylated the N-terminal domain of vimentin on serine 82. Phosphorylation of vimentin and the formation of aggresomes were required for the replication of EV71 since the latter was decreased markedly after phosphorylation was blocked by KN93, a CaMK-II inhibitor. Thus, as one of the consequences of CaMK-II activation, vimentin phosphorylation and rearrangement may support virus replication by playing a structural role for the formation of the replication factories. Collectively, this study identified the replication centers of EV71 in human astrocyte cells. This may help us understand the replication mechanism and pathogenesis of EV71 in human.

  5. Human Cementum Protein 1 induces expression of bone and cementum proteins by human gingival fibroblasts

    International Nuclear Information System (INIS)

    Carmona-Rodriguez, Bruno; Alvarez-Perez, Marco Antonio; Narayanan, A. Sampath; Zeichner-David, Margarita; Reyes-Gasga, Jose; Molina-Guarneros, Juan; Garcia-Hernandez, Ana Lilia; Suarez-Franco, Jose Luis; Chavarria, Ivet Gil; Villarreal-Ramirez, Eduardo; Arzate, Higinio

    2007-01-01

    We recently presented evidence showing that a human cementoblastoma-derived protein, named Cementum Protein 1 (CEMP1) may play a role as a local regulator of cementoblast differentiation and cementum-matrix mineralization. This protein was shown to be expressed by cementoblasts and progenitor cells localized in the periodontal ligament. In this study we demonstrate that transfection of CEMP1 into human gingival fibroblasts (HGF) induces mineralization and expression of bone and cementum-matrix proteins. The transfected HGF cells had higher alkaline phosphatase activity and proliferation rate and they expressed genes for alkaline phosphatase, bone sialoprotein, osteocalcin, osteopontin, the transcription factor Runx2/Cbfa1, and cementum attachment protein (CAP). They also produced biological-type hydroxyapatite. These findings indicate that the CEMP1 might participate in differentiation and mineralization of nonosteogenic cells, and that it might have a potential function in cementum and bone formation

  6. Lysophosphatidic acid induces reactive oxygen species generation by activating protein kinase C in PC-3 human prostate cancer cells

    International Nuclear Information System (INIS)

    Lin, Chu-Cheng; Lin, Chuan-En; Lin, Yueh-Chien; Ju, Tsai-Kai; Huang, Yuan-Li; Lee, Ming-Shyue; Chen, Jiun-Hong; Lee, Hsinyu

    2013-01-01

    Highlights: •LPA induces ROS generation through LPA 1 and LPA 3 . •LPA induces ROS generation by activating PLC. •PKCζ mediates LPA-induced ROS generation. -- Abstract: Prostate cancer is one of the most frequently diagnosed cancers in males, and PC-3 is a cell model popularly used for investigating the behavior of late stage prostate cancer. Lysophosphatidic acid (LPA) is a lysophospholipid that mediates multiple behaviors in cancer cells, such as proliferation, migration and adhesion. We have previously demonstrated that LPA enhances vascular endothelial growth factor (VEGF)-C expression in PC-3 cells by activating the generation of reactive oxygen species (ROS), which is known to be an important mediator in cancer progression. Using flow cytometry, we showed that LPA triggers ROS generation within 10 min and that the generated ROS can be suppressed by pretreatment with the NADPH oxidase (Nox) inhibitor diphenylene iodonium. In addition, transfection with LPA 1 and LPA 3 siRNA efficiently blocked LPA-induced ROS production, suggesting that both receptors are involved in this pathway. Using specific inhibitors and siRNA, phospholipase C (PLC) and protein kinase C (PKC) were also suggested to participate in LPA-induced ROS generation. Overall, we demonstrated that LPA induces ROS generation in PC-3 prostate cancer cells and this is mediated through the PLC/PKC/Nox pathway

  7. Lysophosphatidic acid induces reactive oxygen species generation by activating protein kinase C in PC-3 human prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chu-Cheng; Lin, Chuan-En; Lin, Yueh-Chien [Institute of Zoology, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Ju, Tsai-Kai [Instrumentation Center, National Taiwan University, Taipei, Taiwan, ROC (China); Technology Commons, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Huang, Yuan-Li [Department of Biotechnology, Asia University, Taichung, Taiwan, ROC (China); Lee, Ming-Shyue [Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC (China); Chen, Jiun-Hong [Institute of Zoology, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Department of Life Science, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Lee, Hsinyu, E-mail: hsinyu@ntu.edu.tw [Institute of Zoology, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Department of Life Science, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Center for Biotechnology, National Taiwan University, Taipei, Taiwan, ROC (China); Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan, ROC (China)

    2013-11-01

    Highlights: •LPA induces ROS generation through LPA{sub 1} and LPA{sub 3}. •LPA induces ROS generation by activating PLC. •PKCζ mediates LPA-induced ROS generation. -- Abstract: Prostate cancer is one of the most frequently diagnosed cancers in males, and PC-3 is a cell model popularly used for investigating the behavior of late stage prostate cancer. Lysophosphatidic acid (LPA) is a lysophospholipid that mediates multiple behaviors in cancer cells, such as proliferation, migration and adhesion. We have previously demonstrated that LPA enhances vascular endothelial growth factor (VEGF)-C expression in PC-3 cells by activating the generation of reactive oxygen species (ROS), which is known to be an important mediator in cancer progression. Using flow cytometry, we showed that LPA triggers ROS generation within 10 min and that the generated ROS can be suppressed by pretreatment with the NADPH oxidase (Nox) inhibitor diphenylene iodonium. In addition, transfection with LPA{sub 1} and LPA{sub 3} siRNA efficiently blocked LPA-induced ROS production, suggesting that both receptors are involved in this pathway. Using specific inhibitors and siRNA, phospholipase C (PLC) and protein kinase C (PKC) were also suggested to participate in LPA-induced ROS generation. Overall, we demonstrated that LPA induces ROS generation in PC-3 prostate cancer cells and this is mediated through the PLC/PKC/Nox pathway.

  8. The Natural Stilbenoid Piceatannol Decreases Activity and Accelerates Apoptosis of Human Neutrophils: Involvement of Protein Kinase C

    Directory of Open Access Journals (Sweden)

    Viera Jancinova

    2013-01-01

    Full Text Available Neutrophils are able to release cytotoxic substances and inflammatory mediators, which, along with their delayed apoptosis, have a potential to maintain permanent inflammation. Therefore, treatment of diseases associated with chronic inflammation should be focused on neutrophils; formation of reactive oxygen species and apoptosis of these cells represent two promising targets for pharmacological intervention. Piceatannol, a naturally occurring stilbenoid, has the ability to reduce the toxic action of neutrophils. This substance decreased the amount of oxidants produced by neutrophils both extra- and intracellularly. Radicals formed within neutrophils (fulfilling a regulatory role were reduced to a lesser extent than extracellular oxidants, potentially dangerous for host tissues. Moreover, piceatannol did not affect the phosphorylation of p40phox—a component of NADPH oxidase, responsible for the assembly of functional oxidase in intracellular (granular membranes. The stilbenoid tested elevated the percentage of early apoptotic neutrophils, inhibited the activity of protein kinase C (PKC—the main regulatory enzyme in neutrophils, and reduced phosphorylation of PKC isoforms α, βII, and δ on their catalytic region. The results indicated that piceatannol may be useful as a complementary medicine in states associated with persisting neutrophil activation and with oxidative damage of tissues.

  9. The T alpha 2 nuclear protein binding site from the human T cell receptor alpha enhancer functions as both a T cell-specific transcriptional activator and repressor

    OpenAIRE

    1990-01-01

    T cell-specific expression of the human T cell receptor alpha (TCR- alpha) gene is regulated by the interaction of variable region promoter elements with a transcriptional enhancer that is located 4.5 kb 3' of the TCR-alpha constant region (C alpha) gene segment. The minimal TCR- alpha enhancer is composed of two nuclear protein binding sites, T alpha 1 and T alpha 2, that are both required for the T cell-specific activity of the enhancer. The T alpha 1 binding site contains a consensus cAMP ...

  10. A direct thrombin inhibitor suppresses protein C activation and factor Va degradation in human plasma: Possible mechanisms of paradoxical enhancement of thrombin generation.

    Science.gov (United States)

    Kamisato, Chikako; Furugohri, Taketoshi; Morishima, Yoshiyuki

    2016-05-01

    We have demonstrated that antithrombin (AT)-independent thrombin inhibitors paradoxically increase thrombin generation (TG) in human plasma in a thrombomodulin (TM)- and protein C (PC)-dependent manner. We determined the effects of AT-independent thrombin inhibitors on the negative-feedback system, activation of PC and production and degradation of factor Va (FVa), as possible mechanisms underlying the paradoxical enhancement of TG. TG in human plasma containing 10nM TM was assayed by means of the calibrated automated thrombography. As an index of PC activation, plasma concentration of activated PC-PC inhibitor complex (aPC-PCI) was measured. The amounts of FVa heavy chain and its degradation product (FVa(307-506)) were examined by western blotting. AT-independent thrombin inhibitors, melagatran and dabigatran (both at 25-600nM) and 3-30μg/ml active site-blocked thrombin (IIai), increased peak levels of TG. Melagatran, dabigatran and IIai significantly decreased plasma concentration of aPC-PCI complex at 25nM or more, 75nM or more, and 10 and 30μg/ml, respectively. Melagatran (300nM) significantly increased FVa and decreased FVa(307-506). In contrast, a direct factor Xa inhibitor edoxaban preferentially inhibited thrombin generation (≥25nM), and higher concentrations were required to inhibit PC activation (≥150nM) and FVa degradation (300nM). The present study suggests that the inhibitions of protein C activation and subsequent degradation of FVa and increase in FVa by antithrombin-independent thrombin inhibitors may contribute to the paradoxical TG enhancement, and edoxaban may inhibit PC activation and FVa degradation as a result of TG suppression. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Artocarpin Induces Apoptosis in Human Cutaneous Squamous Cell Carcinoma HSC-1 Cells and Its Cytotoxic Activity Is Dependent on Protein-Nutrient Concentration

    Directory of Open Access Journals (Sweden)

    Stephen Chu-Sung Hu

    2015-01-01

    Full Text Available Artocarpin, a natural prenylated flavonoid, has been shown to have various biological properties. However, its effects on human cutaneous squamous cell carcinoma (SCC have not been previously investigated. We set out to determine whether artocarpin has cytotoxic effects on SCC cells and whether its pharmacological activity is dependent on protein-nutrient concentration. Our results showed that treatment of HSC-1 cells (a human cutaneous SCC cell line with artocarpin decreased cell viability and induced cell apoptosis by increasing caspase 3/7 activity. These effects were more pronounced at low fetal bovine serum (FBS concentrations. Artocarpin induced an increase in the level of phospho-p38 and a decrease in the levels of phospho-ERK, phospho-JNK, phospho-Akt, phospho-mTOR, and phospho-S6K. High FBS concentrations in the culture media inhibited and delayed the uptake of artocarpin from the extracellular compartment (culture media into the intracellular compartment, as determined by high performance liquid chromatography (HPLC analysis. In conclusion, artocarpin induces apoptosis in HSC-1 cells through modulation of MAPK and Akt/mTOR pathways. Binding of artocarpin to proteins in the FBS may inhibit cellular uptake and reduce the cytotoxic activity of artocarpin on HSC-1 cells. Therefore, artocarpin may have potential use in the future as a form of treatment for cutaneous SCC.

  12. The MAP kinase-activated protein kinase Rck2p regulates cellular responses to cell wall stresses, filamentation and virulence in the human fungal pathogen Candida albicans.

    Science.gov (United States)

    Li, Xichuan; Du, Wei; Zhao, Jingwen; Zhang, Lilin; Zhu, Zhiyan; Jiang, Linghuo

    2010-06-01

    Rck2p is the Hog1p-MAP kinase-activated protein kinase required for the attenuation of protein synthesis in response to an osmotic challenge in Saccharomyces cerevisiae. Rck2p also regulates rapamycin sensitivity in both S. cerevisiae and Candida albicans. In this study, we demonstrate that the deletion of CaRCK2 renders C. albicans cells sensitive to, and CaRck2p translocates from the cytosol to the nucleus in response to, cell wall stresses caused by Congo red, Calcoflor White, elevated heat and zymolyase. However, the kinase activity of CaRck2p is not required for the cellular response to these cell wall stresses. Furthermore, transcripts of cell wall protein-encoding genes CaBGL2, CaHWP1 and CaXOG1 are reduced in C. albicans cells lacking CaRCK2. The deletion of CaRCK2 also reduces the in vitro filamentation of C. albicans and its virulence in a mouse model of systemic candidasis. The kinase activity of CaRck2p is required for the virulence, but not for the in vitro filamentation, in C. albicans. Therefore, Rck2p regulates cellular responses to cell wall stresses, filamentation and virulence in the human fungal pathogen C. albicans.

  13. A Single Amino Acid Difference between Mouse and Human 5-Lipoxygenase Activating Protein (FLAP) Explains the Speciation and Differential Pharmacology of Novel FLAP Inhibitors.

    Science.gov (United States)

    Blevitt, Jonathan M; Hack, Michael D; Herman, Krystal; Chang, Leon; Keith, John M; Mirzadegan, Tara; Rao, Navin L; Lebsack, Alec D; Milla, Marcos E

    2016-06-10

    5-Lipoxygenase activating protein (FLAP) plays a critical role in the metabolism of arachidonic acid to leukotriene A4, the precursor to the potent pro-inflammatory mediators leukotriene B4 and leukotriene C4 Studies with small molecule inhibitors of FLAP have led to the discovery of a drug binding pocket on the protein surface, and several pharmaceutical companies have developed compounds and performed clinical trials. Crystallographic studies and mutational analyses have contributed to a general understanding of compound binding modes. During our own efforts, we identified two unique chemical series. One series demonstrated strong inhibition of human FLAP but differential pharmacology across species and was completely inactive in assays with mouse or rat FLAP. The other series was active across rodent FLAP, as well as human and dog FLAP. Comparison of rodent and human FLAP amino acid sequences together with an analysis of a published crystal structure led to the identification of amino acid residue 24 in the floor of the putative binding pocket as a likely candidate for the observed speciation. On that basis, we tested compounds for binding to human G24A and mouse A24G FLAP mutant variants and compared the data to that generated for wild type human and mouse FLAP. These studies confirmed that a single amino acid mutation was sufficient to reverse the speciation observed in wild type FLAP. In addition, a PK/PD method was established in canines to enable preclinical profiling of mouse-inactive compounds. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Protein expression profiling of inflammatory mediators in human temporal lobe epilepsy reveals co-activation of multiple chemokines and cytokines

    Directory of Open Access Journals (Sweden)

    Kan Anne A

    2012-08-01

    Full Text Available Abstract Mesial temporal lobe epilepsy (mTLE is a chronic and often treatment-refractory brain disorder characterized by recurrent seizures originating from the hippocampus. The pathogenic mechanisms underlying mTLE remain largely unknown. Recent clinical and experimental evidence supports a role of various inflammatory mediators in mTLE. Here, we performed protein expression profiling of 40 inflammatory mediators in surgical resection material from mTLE patients with and without hippocampal sclerosis, and autopsy controls using a multiplex bead-based immunoassay. In mTLE patients we identified 21 upregulated inflammatory mediators, including 10 cytokines and 7 chemokines. Many of these upregulated mediators have not previously been implicated in mTLE (for example, CCL22, IL-7 and IL-25. Comparing the three patient groups, two main hippocampal expression patterns could be distinguished, pattern I (for example, IL-10 and IL-25 showing increased expression in mTLE + HS patients compared to mTLE-HS and controls, and pattern II (for example, CCL4 and IL-7 showing increased expression in both mTLE groups compared to controls. Upregulation of a subset of inflammatory mediators (for example, IL-25 and IL-7 could not only be detected in the hippocampus of mTLE patients, but also in the neocortex. Principle component analysis was used to cluster the inflammatory mediators into several components. Follow-up analyses of the identified components revealed that the three patient groups could be discriminated based on their unique expression profiles. Immunocytochemistry showed that IL-25 IR (pattern I and CCL4 IR (pattern II were localized in astrocytes and microglia, whereas IL-25 IR was also detected in neurons. Our data shows co-activation of multiple inflammatory mediators in hippocampus and neocortex of mTLE patients, indicating activation of multiple pro- and anti-epileptogenic immune pathways in this disease.

  15. cAMP response element binding protein (CREB activates transcription via two distinct genetic elements of the human glucose-6-phosphatase gene

    Directory of Open Access Journals (Sweden)

    Stefano Luisa

    2005-01-01

    Full Text Available Abstract Background The enzyme glucose-6-phosphatase catalyzes the dephosphorylation of glucose-6-phosphatase to glucose, the final step in the gluconeogenic and glycogenolytic pathways. Expression of the glucose-6-phosphatase gene is induced by glucocorticoids and elevated levels of intracellular cAMP. The effect of cAMP in regulating glucose-6-phosphatase gene transcription was corroborated by the identification of two genetic motifs CRE1 and CRE2 in the human and murine glucose-6-phosphatase gene promoter that resemble cAMP response elements (CRE. Results The cAMP response element is a point of convergence for many extracellular and intracellular signals, including cAMP, calcium, and neurotrophins. The major CRE binding protein CREB, a member of the basic region leucine zipper (bZIP family of transcription factors, requires phosphorylation to become a biologically active transcriptional activator. Since unphosphorylated CREB is transcriptionally silent simple overexpression studies cannot be performed to test the biological role of CRE-like sequences of the glucose-6-phosphatase gene. The use of a constitutively active CREB2/CREB fusion protein allowed us to uncouple the investigation of target genes of CREB from the variety of signaling pathways that lead to an activation of CREB. Here, we show that this constitutively active CREB2/CREB fusion protein strikingly enhanced reporter gene transcription mediated by either CRE1 or CRE2 derived from the glucose-6-phosphatase gene. Likewise, reporter gene transcription was enhanced following expression of the catalytic subunit of cAMP-dependent protein kinase (PKA in the nucleus of transfected cells. In contrast, activating transcription factor 2 (ATF2, known to compete with CREB for binding to the canonical CRE sequence 5'-TGACGTCA-3', did not transactivate reporter genes containing CRE1, CRE2, or both CREs derived from the glucose-6-phosphatase gene. Conclusions Using a constitutively active CREB2

  16. A δ38 deletion variant of human transketolase as a model of transketolase-like protein 1 exhibits no enzymatic activity.

    Directory of Open Access Journals (Sweden)

    Stefan Schneider

    Full Text Available Besides transketolase (TKT, a thiamin-dependent enzyme of the pentose phosphate pathway, the human genome encodes for two closely related transketolase-like proteins, which share a high sequence identity with TKT. Transketolase-like protein 1 (TKTL1 has been implicated in cancerogenesis as its cellular expression levels were reported to directly correlate with invasion efficiency of cancer cells and patient mortality. It has been proposed that TKTL1 exerts its function by catalyzing an unusual enzymatic reaction, a hypothesis that has been the subject of recent controversy. The most striking difference between TKTL1 and TKT is a deletion of 38 consecutive amino acids in the N-terminal domain of the former, which constitute part of the active site in authentic TKT. Our structural and sequence analysis suggested that TKTL1 might not possess transketolase activity. In order to test this hypothesis in the absence of a recombinant expression system for TKTL1 and resilient data on its biochemical properties, we have engineered and biochemically characterized a "pseudo-TKTL1" Δ38 deletion variant of human TKT (TKTΔ38 as a viable model of TKTL1. Although the isolated protein is properly folded under in vitro conditions, both thermal stability as well as stability of the TKT-specific homodimeric assembly are markedly reduced. Circular dichroism and NMR spectroscopic analysis further indicates that TKTΔ38 is unable to bind the thiamin cofactor in a specific manner, even at superphysiological concentrations. No transketolase activity of TKTΔ38 can be detected for conversion of physiological sugar substrates thus arguing against an intrinsically encoded enzymatic function of TKTL1 in tumor cell metabolism.

  17. Examination of transcript amounts and activity of protein kinase CK2 in muscle lysates of different types of human muscle pathologies.

    Science.gov (United States)

    Heuss, Dieter; Klascinski, Janine; Schubert, Steffen W; Moriabadi, Tehmur; Lochmüller, Hanns; Hashemolhosseini, Said

    2008-09-01

    Motoneurons release the heparansulfate proteoglycan agrin and thereby activate the muscle-specific receptor tyrosine kinase (MuSK), which is the main organizer of subsynaptic specializations at the neuromuscular junction. Recently, we showed that (1) the protein kinase CK2 interacts with the intracellular region of MuSK; (2) the CK2 protein is enriched and co-localized with MuSK at postsynaptic specializations; (3) CK2-mediated phosphorylation of serine residues within a specific MuSK epitope, named the kinase insert, regulates acetylcholine receptor (AChR) clustering; (4) muscle-specific CK2beta knockout mice develop a myasthenic phenotype due to impaired muscle endplate structure and function (see Genes Dev 20(13):1800-1816, 2006). Here, we investigated for the first time if CK2 is modulated in biopsies from human patients. To this end, we measured transcript amounts of the subunits CK2alpha and CK2beta and determined holoenzyme CK2 activity in 34 muscle biopsies of human patients with different muscle pathologies.

  18. The protein pheromone Er-1 of the ciliate Euplotes raikovi stimulates human T-cell activity: Involvement of interleukin-2 system

    Energy Technology Data Exchange (ETDEWEB)

    Cervia, Davide, E-mail: d.cervia@unitus.it [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Department of Biomedical and Clinical Sciences, “Luigi Sacco” University Hospital, University of Milan, Milano (Italy); Catalani, Elisabetta; Belardinelli, Maria Cristina [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Perrotta, Cristiana [Department of Biomedical and Clinical Sciences, “Luigi Sacco” University Hospital, University of Milan, Milano (Italy); Picchietti, Simona [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Alimenti, Claudio [Department of Environmental and Natural Sciences, University of Camerino, Camerino (Italy); Casini, Giovanni; Fausto, Anna Maria [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Vallesi, Adriana [Department of Environmental and Natural Sciences, University of Camerino, Camerino (Italy)

    2013-02-01

    Water-soluble protein signals (pheromones) of the ciliate Euplotes have been supposed to be functional precursors of growth factors and cytokines that regulate cell–cell interaction in multi-cellular eukaryotes. This work provides evidence that native preparations of the Euplotes raikovi pheromone Er-1 (a helical protein of 40 amino acids) specifically increases viability, DNA synthesis, proliferation, and the production of interferon-γ, tumor necrosis factor-α, interleukin (IL)-1β, IL-2, and IL-13 in human Jurkat T-cells. Also, Er-1 significantly decreases the mRNA levels of the β and γ subunits of IL-2 receptor (IL-2R), while the mRNA levels of the α subunit appeared to be not affected. Jurkat T-cell treatments with Er-1 induced the down-regulation of the IL-2Rα subunit by a reversible and time-dependent endocytosis, and increased the levels of phosphorylation of the extracellular signal-regulated kinases (ERK). The cell-type specificity of these effects was supported by the finding that Er-1, although unable to directly influence the growth of human glioma U-373 cells, induced Jurkat cells to synthesize and release factors that, in turn, inhibited the U-373 cell proliferation. Overall, these findings imply that Er-1 coupling to IL-2R and ERK immuno-enhances T-cell activity, and that this effect likely translates to an inhibition of glioma cell growth. -- Highlights: ► Euplotes pheromone Er-1 increases the growth of human Jurkat T-cells. ► Er-1 increases the T-cell production of specific cytokines. ► Er-1 activates interleukin-2 receptor and extracellular signal-regulated kinases. ► The immuno-enhancing effect of Er-1 on Jurkat cells translates to an inhibition of human glioma cell growth.

  19. 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

  20. Estrogen induction of telomerase activity through regulation of the mitogen-activated protein kinase (MAPK dependent pathway in human endometrial cancer cells.

    Directory of Open Access Journals (Sweden)

    Chunxiao Zhou

    Full Text Available Given that prolonged exposure to estrogen and increased telomerase activity are associated with endometrial carcinogenesis, our objective was to evaluate the interaction between the MAPK pathway and estrogen induction of telomerase activity in endometrial cancer cells. Estradiol (E2 induced telomerase activity and hTERT mRNA expression in the estrogen receptor (ER-α positive, Ishikawa endometrial cancer cell line. UO126, a highly selective inhibitor of MEK1/MEK2, inhibited telomerase activity and hTERT mRNA expression induced by E2. Similar results were also found after transfection with ERK 1/2-specific siRNA. Treatment with E2 resulted in rapid phosphorylation of p44/42 MAPK and increased MAPK activity which was abolished by UO126. The hTERT promoter contains two estrogen response elements (EREs, and luciferase assays demonstrate that these EREs are activated by E2. Exposure to UO126 or ERK 1/2-specific siRNA in combination with E2 counteracted the stimulatory effect of E2 on luciferase activity from these EREs. These findings suggest that E2-induction of telomerase activity is mediated via the MAPK pathway in human endometrial cancer cells.

  1. Transcriptional Repression and Protein Degradation of the Ca2+-Activated K+ Channel KCa1.1 by Androgen Receptor Inhibition in Human Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Anowara Khatun

    2018-04-01

    Full Text Available The large-conductance Ca2+-activated K+ channel KCa1.1 plays an important role in the promotion of breast cancer cell proliferation and metastasis. The androgen receptor (AR is proposed as a therapeutic target for AR-positive advanced triple-negative breast cancer. We herein investigated the effects of a treatment with antiandrogens on the functional activity, activation kinetics, transcriptional expression, and protein degradation of KCa1.1 in human breast cancer MDA-MB-453 cells using real-time PCR, Western blotting, voltage-sensitive dye imaging, and whole-cell patch clamp recording. A treatment with the antiandrogen bicalutamide or enzalutamide for 48 h significantly suppressed (1 depolarization responses induced by paxilline (PAX, a specific KCa1.1 blocker and (2 PAX-sensitive outward currents induced by the depolarizing voltage step. The expression levels of KCa1.1 transcripts and proteins were significantly decreased in MDA-MB-453 cells, and the protein degradation of KCa1.1 mainly contributed to reductions in KCa1.1 activity. Among the eight regulatory β and γ subunits, LRRC26 alone was expressed at high levels in MDA-MB-453 cells and primary and metastatic breast cancer tissues, whereas no significant changes were observed in the expression levels of LRRC26 and activation kinetics of PAX-sensitive outward currents in MDA-MB-453 cells by the treatment with antiandrogens. The treatment with antiandrogens up-regulated the expression of the ubiquitin E3 ligases, FBW7, MDM2, and MDM4 in MDA-MB-453 cells, and the protein degradation of KCa1.1 was significantly inhibited by the respective siRNA-mediated blockade of FBW7 and MDM2. Based on these results, we concluded that KCa1.1 is an androgen-responsive gene in AR-positive breast cancer cells, and its down-regulation through enhancements in its protein degradation by FBW7 and/or MDM2 may contribute, at least in part, to the antiproliferative and antimetastatic effects of antiandrogens in

  2. Affinity purification of recombinant human plasminogen activator ...

    African Journals Online (AJOL)

    Affinity purification of recombinant human plasminogen activator from ... Screening antibody was performed using rhPA milk in an ELISA-elution assay. ... useful for purifying other tPA mutants or other novel recombinant milkderived proteins.

  3. Piperine activates human pregnane X receptor to induce the expression of cytochrome P450 3A4 and multidrug resistance protein 1

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yue-Ming; Lin, Wenwei; Chai, Sergio C.; Wu, Jing; Ong, Su Sien [Department of Chemical Biology and Therapeutics, St. Jude Children' s Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105 (United States); Schuetz, Erin G. [Department of Pharmaceutical Sciences, St. Jude Children' s Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105 (United States); Chen, Taosheng, E-mail: taosheng.chen@stjude.org [Department of Chemical Biology and Therapeutics, St. Jude Children' s Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105 (United States)

    2013-10-01

    Activation of the pregnane X receptor (PXR) and subsequently its target genes, including those encoding drug transporters and metabolizing enzymes, while playing substantial roles in xenobiotic detoxification, might cause undesired drug-drug interactions. Recently, an increased awareness has been given to dietary components for potential induction of diet–drug interactions through activation of PXR. Here, we studied, whether piperine (PIP), a major component extracted from the widely-used daily spice black pepper, could induce PXR-mediated expression of cytochrome P450 3A4 (CYP3A4) and multidrug resistance protein 1 (MDR1). Our results showed that PIP activated human PXR (hPXR)-mediated CYP3A4 and MDR1 expression in human hepatocytes, intestine cells, and a mouse model; PIP activated hPXR by recruiting its coactivator SRC-1 in both cellular and cell-free systems; PIP bound to the hPXR ligand binding domain in a competitive ligand binding assay in vitro. The dichotomous effects of PIP on induction of CYP3A4 and MDR1 expression observed here and inhibition of their activity reported elsewhere challenges the potential use of PIP as a bioavailability enhancer and suggests that caution should be taken in PIP consumption during drug treatment in patients, particularly those who favor daily pepper spice or rely on certain pepper remedies. - Highlights: • Piperine induces PXR-mediated CYP3A4 and MDR1 expression. • Piperine activates PXR by binding to PXR and recruiting coactivator SRC-1. • Piperine induces PXR activation in vivo. • Caution should be taken in piperine consumption during drug treatment.

  4. Inhibition of mitogen-activated protein kinase kinase, DNA methyltransferase, and transforming growth factor-β promotes differentiation of human induced pluripotent stem cells into enterocytes.

    Science.gov (United States)

    Kodama, Nao; Iwao, Takahiro; Kabeya, Tomoki; Horikawa, Takashi; Niwa, Takuro; Kondo, Yuki; Nakamura, Katsunori; Matsunaga, Tamihide

    2016-06-01

    We previously reported that small-molecule compounds were effective in generating pharmacokinetically functional enterocytes from human induced pluripotent stem (iPS) cells. In this study, to determine whether the compounds promote the differentiation of human iPS cells into enterocytes, we investigated the effects of a combination of mitogen-activated protein kinase kinase (MEK), DNA methyltransferase (DNMT), and transforming growth factor (TGF)-β inhibitors on intestinal differentiation. Human iPS cells cultured on feeder cells were differentiated into endodermal cells by activin A. These endodermal-like cells were then differentiated into intestinal stem cells by fibroblast growth factor 2. Finally, the cells were differentiated into enterocyte cells by epidermal growth factor and small-molecule compounds. After differentiation, mRNA expression levels and drug-metabolizing enzyme activities were measured. The mRNA expression levels of the enterocyte marker sucrase-isomaltase and the major drug-metabolizing enzyme cytochrome P450 (CYP) 3A4 were increased by a combination of MEK, DNMT, and TGF-β inhibitors. The mRNA expression of CYP3A4 was markedly induced by 1α,25-dihydroxyvitamin D3. Metabolic activities of CYP1A1/2, CYP2B6, CYP2C9, CYP2C19, CYP3A4/5, UDP-glucuronosyltransferase, and sulfotransferase were also observed in the differentiated cells. In conclusion, MEK, DNMT, and TGF-β inhibitors can be used to promote the differentiation of human iPS cells into pharmacokinetically functional enterocytes. Copyright © 2016 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

  5. Canine distemper virus neutralization activity is low in human serum and it is sensitive to an amino acid substitution in the hemagglutinin protein

    International Nuclear Information System (INIS)

    Zhang, Xinsheng; Wallace, Olivia L.; Domi, Arban; Wright, Kevin J.; Driscoll, Jonathan; Anzala, Omu; Sanders, Eduard J.; Kamali, Anatoli; Karita, Etienne; Allen, Susan; Fast, Pat; Gilmour, Jill; Price, Matt A.; Parks, Christopher L.

    2015-01-01

    Serum was analyzed from 146 healthy adult volunteers in eastern Africa to evaluate measles virus (MV) and canine distemper virus (CDV) neutralizing antibody (nAb) prevalence and potency. MV plaque reduction neutralization test (PRNT) results indicated that all sera were positive for MV nAbs. Furthermore, the 50% neutralizing dose (ND50) for the majority of sera corresponded to antibody titers induced by MV vaccination. CDV nAbs titers were low and generally were detected in sera with high MV nAb titers. A mutant CDV was generated that was less sensitive to neutralization by human serum. The mutant virus genome had 10 nucleotide substitutions, which coded for single amino acid substitutions in the fusion (F) and hemagglutinin (H) glycoproteins and two substitutions in the large polymerase (L) protein. The H substitution occurred in a conserved region involved in receptor interactions among morbilliviruses, implying that this region is a target for cross-reactive neutralizing antibodies. - Highlights: • Screened 146 serum samples for measles virus (MV) and canine distemper virus (CDV) neutralizing antibody (nAb). • MV nAb is prevalent in the sera. • CDV neutralizing activity is generally low or absent and when detected it is present in sera with high MV nAb titers. • A neutralization-resistant CDV mutant was isolated using human serum selection. • A mutation was identified in the receptor-binding region of CDV hemagglutinin protein that confers the neutralization resistance

  6. Canine distemper virus neutralization activity is low in human serum and it is sensitive to an amino acid substitution in the hemagglutinin protein

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xinsheng, E-mail: xzhang@iavi.org [AIDS Vaccine Design and Development Laboratory, International AIDS Vaccine Initiative (IAVI), Brooklyn, NY (United States); Molecular and Cellular Biology Program, State University of New York, Brooklyn, NY (United States); Wallace, Olivia L.; Domi, Arban; Wright, Kevin J.; Driscoll, Jonathan [AIDS Vaccine Design and Development Laboratory, International AIDS Vaccine Initiative (IAVI), Brooklyn, NY (United States); Anzala, Omu [Kenya AIDS Vaccine Initiative (KAVI)-Institute of Clinical Research, Nairobi (Kenya); Sanders, Eduard J. [Centre for Geographic Medicine Research, Kenya Medical Research Institute (KEMRI), Kilifi, Kenya & Centre for Clinical Vaccinology and Tropical Medicine, University of Oxford, Headington (United Kingdom); Kamali, Anatoli [MRC/UVRI Uganda Virus Research Unit on AIDS, Masaka and Entebbe (Uganda); Karita, Etienne [Projet San Francisco, Kigali (Rwanda); Allen, Susan [Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA (United States); Fast, Pat [Department of Medical Affairs, International AIDS Vaccine Initiative, NY, NY (United States); Gilmour, Jill [Human Immunology Laboratory, International AIDS Vaccine Initiative, London (United Kingdom); Price, Matt A. [Department of Medical Affairs, International AIDS Vaccine Initiative, NY, NY (United States); Department of Epidemiology and Biostatistics, University of California at San Francisco, San Francisco, CA (United States); Parks, Christopher L. [AIDS Vaccine Design and Development Laboratory, International AIDS Vaccine Initiative (IAVI), Brooklyn, NY (United States); Molecular and Cellular Biology Program, State University of New York, Brooklyn, NY (United States)

    2015-08-15

    Serum was analyzed from 146 healthy adult volunteers in eastern Africa to evaluate measles virus (MV) and canine distemper virus (CDV) neutralizing antibody (nAb) prevalence and potency. MV plaque reduction neutralization test (PRNT) results indicated that all sera were positive for MV nAbs. Furthermore, the 50% neutralizing dose (ND50) for the majority of sera corresponded to antibody titers induced by MV vaccination. CDV nAbs titers were low and generally were detected in sera with high MV nAb titers. A mutant CDV was generated that was less sensitive to neutralization by human serum. The mutant virus genome had 10 nucleotide substitutions, which coded for single amino acid substitutions in the fusion (F) and hemagglutinin (H) glycoproteins and two substitutions in the large polymerase (L) protein. The H substitution occurred in a conserved region involved in receptor interactions among morbilliviruses, implying that this region is a target for cross-reactive neutralizing antibodies. - Highlights: • Screened 146 serum samples for measles virus (MV) and canine distemper virus (CDV) neutralizing antibody (nAb). • MV nAb is prevalent in the sera. • CDV neutralizing activity is generally low or absent and when detected it is present in sera with high MV nAb titers. • A neutralization-resistant CDV mutant was isolated using human serum selection. • A mutation was identified in the receptor-binding region of CDV hemagglutinin protein that confers the neutralization resistance.

  7. Human herpesvirus 6B U19 protein is a PML-regulated transcriptional activator that localizes to nuclear foci in a PML-independent manner

    DEFF Research Database (Denmark)

    Kofod-Olsen, Emil; Ross-Hansen, Katrine; Mikkelsen, Jacob Giehm

    2008-01-01

    Human herpesvirus 6B (HHV-6B) contains an IE-B domain spanning open reading frames U16/17-U19, based on homology with human cytomegalovirus. Here, the protein product, U19, of the HHV-6B U19 gene is identified as a 47 kDa transcriptional activator. HHV-6B infection or overexpression of U19...... transactivated the RANTES promoter. Mutational analysis of the promoter indicated that transactivation was not critically dependent on the promoter sites CRE, NF-kappaB, ISRE or NF-IL6. ND10 are nuclear substructures that are involved in several cellular regulatory pathways, including those controlling gene...... structure, U19 also localized to the centre of ND10. Knockdown of PML by small interfering RNA did not prevent U19 localization to ND10-like foci, but instead led to a fourfold increase in U19-induced transcription from the RANTES promoter. Generation of four truncated U19 proteins indicated that the N...

  8. A milk protein gene promoter directs the expression of human tissue plasminogen activator cDNA to the mammary gland in transgenic mice

    International Nuclear Information System (INIS)

    Pittius, C.W.; Hennighausen, L.; Lee, E.; Westphal, H.; Nicols, E.; Vitale, J.; Gordon, K.

    1988-01-01

    Whey acidic protein (WAP) is a major whey protein in mouse milk. Its gene is expressed in the lactating mammary gland and is inducible by steroid and peptide hormones. A series of transgenic mice containing a hybrid gene in which human tissue plasminogen activator (tPA) cDNA is under the control of the murine WAP gene promoter had previously been generated. In this study, 21 tissues from lactating and virgin transgenic female mice containing the WAP-tPA hybrid gene were screened for the distribution of murine WAP and human tPA transcripts. Like the endogenous WAP RNA, WAP-tPA RNA was expressed predominantly in mammary gland tissue and appeared to be inducible by lactation. Whereas WAP transcripts were not detected in 22 tissues of virgin mice, low levels of WAP-tPA RNA, which were not modulated during lactation, were found in tongue, kidney, and sublingual gland. These studies demonstrate that the WAP gene promoter can target the expression of a transgene to the mammary gland and that this expression is inducible during lactation

  9. Major proteins in normal human lymphocyte subpopulations separated by fluorescence-activated cell sorting and analyzed by two-dimensional gel electrophoresis

    DEFF Research Database (Denmark)

    Madsen, P S; Hokland, M; Ellegaard, J

    1988-01-01

    markers were observed in all cell types. All the putative protein markers have been identified in the protein database of human peripheral blood mononuclear cells (PBMCs) (see accompanying article by Celis et al.). Comparison of the overall patterns of protein synthesis of the unsorted PBMCs with those...... of the four subpopulations showed that the synthesis of some major PBMC proteins decreased substantially in the sorted subsets. These proteins are most likely not of monocyte origin, as these cells constituted only about 15% of the total PBMCs. Also, the inhibition does not seem to be due to the addition...

  10. [Production of human proteins in the blood of transgenic animals

    NARCIS (Netherlands)

    Massoud, M.; Bischoff, Rainer; Dalemans, W.; Pointu, H.; Attal, J.; Schultz, H.; Clesse, D.; Stinnakre, M.G.; Pavirani, A.; Houdebine, L.M.

    1990-01-01

    The human alpha 1-antitrypsin gene has been microinjected into rabbit embryos. A line of transgenic rabbits has thus been established. Human alpha 1-antitrypsin was found in the blood of transgenic animals at the concentration of 1 mg/ml plasma. The human protein was active and separable from its

  11. Cytoplasmic localization of a functionally active Fanconi anemia group A green fluorescent protein chimera in human 293 cells

    NARCIS (Netherlands)

    Kruyt, FAE; Waisfisz, Q; Dijkmans, LM; Hermsen, M.A.; Youssoufian, H; Arwert, F; Joenje, H

    1997-01-01

    Hypersensitivity to cross-linking agents and predisposition to malignancy are characteristic of the genetically heterogeneous inherited bone marrow failure syndrome, Fanconi anemia (FA). The protein encoded by the recently cloned FA complementation group A gene, FAA, has been expected to localize in

  12. Mechanical unloading of the failing human heart fails to activate the protein kinase B/Akt/glycogen synthase kinase-3beta survival pathway.

    Science.gov (United States)

    Razeghi, Peter; Bruckner, Brian A; Sharma, Saumya; Youker, Keith A; Frazier, O H; Taegtmeyer, Heinrich

    2003-01-01

    Left ventricular assist device (LVAD) support of the failing human heart improves myocyte function and increases cell survival. One potential mechanism underlying this phenomenon is activation of the protein kinase B (PKB)/Akt/glycogen synthase kinase-3beta (GSK-3beta) survival pathway. Left ventricular tissue was obtained both at the time of implantation and explantation of the LVAD (n = 11). Six patients were diagnosed with idiopathic dilated cardiomyopathy, 4 patients with ischemic cardiomyopathy and 1 patient with peripartum cardiomyopathy. The mean duration of LVAD support was 205 +/- 35 days. Myocyte diameter and phosphorylation of ERK were used as indices for reverse remodeling. Transcript levels of genes required for the activation of PKB/Akt (insulin-like growth factor-1, insulin receptor substrate-1) were measured by quantitative RT-PCR. In addition, we measured the relative activity of PKB/Akt and GSK-3beta, and assayed for molecular and histological indices of PKB/Akt activation (cyclooxygenase mRNA levels and glycogen levels). Myocyte diameter and phosphorylation of ERK decreased with LVAD support. In contrast, none of the components of the PKB/Akt/GSK-3beta pathway changed significantly with mechanical unloading. The PKB/Akt/GSK-3beta pathway is not activated during LVAD support. Other signaling pathways must be responsible for the improvement of cellular function and cell survival during LVAD support. Copyright 2003 S. Karger AG, Basel

  13. A Physical Interaction Network of Dengue Virus and Human Proteins*

    Science.gov (United States)

    Khadka, Sudip; Vangeloff, Abbey D.; Zhang, Chaoying; Siddavatam, Prasad; Heaton, Nicholas S.; Wang, Ling; Sengupta, Ranjan; Sahasrabudhe, Sudhir; Randall, Glenn; Gribskov, Michael; Kuhn, Richard J.; Perera, Rushika; LaCount, Douglas J.

    2011-01-01

    Dengue virus (DENV), an emerging mosquito-transmitted pathogen capable of causing severe disease in humans, interacts with host cell factors to create a more favorable environment for replication. However, few interactions between DENV and human proteins have been reported to date. To identify DENV-human protein interactions, we used high-throughput yeast two-hybrid assays to screen the 10 DENV proteins against a human liver activation domain library. From 45 DNA-binding domain clones containing either full-length viral genes or partially overlapping gene fragments, we identified 139 interactions between DENV and human proteins, the vast majority of which are novel. These interactions involved 105 human proteins, including six previously implicated in DENV infection and 45 linked to the replication of other viruses. Human proteins with functions related to the complement and coagulation cascade, the centrosome, and the cytoskeleton were enriched among the DENV interaction partners. To determine if the cellular proteins were required for DENV infection, we used small interfering RNAs to inhibit their expression. Six of 12 proteins targeted (CALR, DDX3X, ERC1, GOLGA2, TRIP11, and UBE2I) caused a significant decrease in the replication of a DENV replicon. We further showed that calreticulin colocalized with viral dsRNA and with the viral NS3 and NS5 proteins in DENV-infected cells, consistent with a direct role for calreticulin in DENV replication. Human proteins that interacted with DENV had significantly higher average degree and betweenness than expected by chance, which provides additional support for the hypothesis that viruses preferentially target cellular proteins that occupy central position in the human protein interaction network. This study provides a valuable starting point for additional investigations into the roles of human proteins in DENV infection. PMID:21911577

  14. A physical interaction network of dengue virus and human proteins.

    Science.gov (United States)

    Khadka, Sudip; Vangeloff, Abbey D; Zhang, Chaoying; Siddavatam, Prasad; Heaton, Nicholas S; Wang, Ling; Sengupta, Ranjan; Sahasrabudhe, Sudhir; Randall, Glenn; Gribskov, Michael; Kuhn, Richard J; Perera, Rushika; LaCount, Douglas J

    2011-12-01

    Dengue virus (DENV), an emerging mosquito-transmitted pathogen capable of causing severe disease in humans, interacts with host cell factors to create a more favorable environment for replication. However, few interactions between DENV and human proteins have been reported to date. To identify DENV-human protein interactions, we used high-throughput yeast two-hybrid assays to screen the 10 DENV proteins against a human liver activation domain library. From 45 DNA-binding domain clones containing either full-length viral genes or partially overlapping gene fragments, we identified 139 interactions between DENV and human proteins, the vast majority of which are novel. These interactions involved 105 human proteins, including six previously implicated in DENV infection and 45 linked to the replication of other viruses. Human proteins with functions related to the complement and coagulation cascade, the centrosome, and the cytoskeleton were enriched among the DENV interaction partners. To determine if the cellular proteins were required for DENV infection, we used small interfering RNAs to inhibit their expression. Six of 12 proteins targeted (CALR, DDX3X, ERC1, GOLGA2, TRIP11, and UBE2I) caused a significant decrease in the replication of a DENV replicon. We further showed that calreticulin colocalized with viral dsRNA and with the viral NS3 and NS5 proteins in DENV-infected cells, consistent with a direct role for calreticulin in DENV replication. Human proteins that interacted with DENV had significantly higher average degree and betweenness than expected by chance, which provides additional support for the hypothesis that viruses preferentially target cellular proteins that occupy central position in the human protein interaction network. This study provides a valuable starting point for additional investigations into the roles of human proteins in DENV infection.

  15. TsAg5, a Taenia solium cysticercus protein with a marginal trypsin-like activity in the diagnosis of human neurocysticercosis.

    Science.gov (United States)

    Rueda, Analiz; Sifuentes, Cecilia; Gilman, Robert H; Gutiérrez, Andrés H; Piña, Ruby; Chile, Nancy; Carrasco, Sebastián; Larson, Sandra; Mayta, Holger; Verástegui, Manuela; Rodriguez, Silvia; Gutiérrez-Correa, Marcel; García, Héctor H; Sheen, Patricia; Zimic, Mirko

    2011-12-01

    Neurocysticercosis is an endemic parasitic disease caused by Taenia solium larva. Although the mechanism of infection is not completely understood, it is likely driven by proteolytic activity that degrades the intestinal wall to facilitate oncosphere penetration and further infection. We analyzed the publicly available T. solium EST/DNA library and identified two contigs comprising a full-length cDNA fragment very similar to Echinococcus granulosus Ag5 protein. The T. solium cDNA sequence included a proteolytic trypsin-like-domain in the C-terminal region, and a thrombospondin type-1 adherence-domain in the N-terminal region. Both the trypsin-like and adherence domains were expressed independently as recombinant proteins in bacterial systems. TsAg5 showed marginal trypsin-like activity and high sequence similarity to Ag5. The purified antigens were tested in a Western immunoblot assay to diagnose human neurocysticercosis. The sensitivity of the trypsin-like-domain was 96.36% in patients infected with extraparenchymal cysts, 75.44% in patients infected with multiple cysts, and 39.62% in patients with a single cyst. Specificity was 76.70%. The thrombospondin type-1 adherence-domain was not specific for neurocysticercosis. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Calcium Hydroxide-induced Proliferation, Migration, Osteogenic Differentiation, and Mineralization via the Mitogen-activated Protein Kinase Pathway in Human Dental Pulp Stem Cells.

    Science.gov (United States)

    Chen, Luoping; Zheng, Lisha; Jiang, Jingyi; Gui, Jinpeng; Zhang, Lingyu; Huang, Yan; Chen, Xiaofang; Ji, Jing; Fan, Yubo

    2016-09-01

    Calcium hydroxide has been extensively used as the gold standard for direct pulp capping in clinical dentistry. It induces proliferation, migration, and mineralization in dental pulp stem cells (DPSCs), but the underlying mechanisms are still unclear. The aim of this study was to investigate the role of the mitogen-activated protein (MAP) kinase pathway in calcium hydroxide-induced proliferation, migration, osteogenic differentiation, and mineralization in human DPSCs. Human DPSCs between passages 3 and 6 were used. DPSCs were preincubated with inhibitors of MAP kinases and cultured with calcium hydroxide. The phosphorylated MAP kinases were detected by Western blot analysis. Cell viability was analyzed via the methylthiazol tetrazolium assay. Cell migration was estimated using the wound healing assay. Alkaline phosphatase (ALP) expression was analyzed using the ALP staining assay. Mineralization was studied by alizarin red staining analysis. Calcium hydroxide significantly promoted the phosphorylation of the c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase. The inhibition of JNK and p38 signaling abolished calcium hydroxide-induced proliferation of DPSCs. The inhibition of JNK, p38, and extracellular signal-regulated kinase signaling suppressed the migration, ALP expression, and mineralization of DPSCs. Our study showed that the MAP kinase pathway was involved in calcium hydroxide-induced proliferation, migration, osteogenic differentiation, and mineralization in human DPSCs. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  17. Type I and Type III Interferons Display Different Dependency on Mitogen-Activated Protein Kinases to Mount an Antiviral State in the Human Gut.

    Science.gov (United States)

    Pervolaraki, Kalliopi; Stanifer, Megan L; Münchau, Stephanie; Renn, Lynnsey A; Albrecht, Dorothee; Kurzhals, Stefan; Senís, Elena; Grimm, Dirk; Schröder-Braunstein, Jutta; Rabin, Ronald L; Boulant, Steeve

    2017-01-01

    Intestinal epithelial cells (IECs) are constantly exposed to commensal flora and pathogen challenges. How IECs regulate their innate immune response to maintain gut homeostasis remains unclear. Interferons (IFNs) are cytokines produced during infections. While type I IFN receptors are ubiquitously expressed, type III IFN receptors are expressed only on epithelial cells. This epithelium specificity strongly suggests exclusive functions at epithelial surfaces, but the relative roles of type I and III IFNs in the establishment of an antiviral innate immune response in human IECs are not clearly defined. Here, we used mini-gut organoids to define the functions of types I and III IFNs to protect the human gut against viral infection. We show that primary non-transformed human IECs, upon viral challenge, upregulate the expression of both type I and type III IFNs at the transcriptional level but only secrete type III IFN in the supernatant. However, human IECs respond to both type I and type III IFNs by producing IFN-stimulated genes that in turn induce an antiviral state. Using genetic ablation of either type I or type III IFN receptors, we show that either IFN can independently restrict virus infection in human IECs. Importantly, we report, for the first time, differences in the mechanisms by which each IFN establishes the antiviral state. Contrary to type I IFN, the antiviral activity induced by type III IFN is strongly dependent on the mitogen-activated protein kinases signaling pathway, suggesting a pathway used by type III IFNs that non-redundantly contributes to the antiviral state. In conclusion, we demonstrate that human intestinal epithelial cells specifically regulate their innate immune response favoring type III IFN-mediated signaling, which allows for efficient protection against pathogens without producing excessive inflammation. Our results strongly suggest that type III IFN constitutes the frontline of antiviral response in the human gut. We propose that

  18. Human holocarboxylase synthetase with a start site at methionine-58 is the predominant nuclear variant of this protein and has catalytic activity

    International Nuclear Information System (INIS)

    Bao, Baolong; Wijeratne, Subhashinee S.K.; Rodriguez-Melendez, Rocio; Zempleni, Janos

    2011-01-01

    Highlights: → Unambiguous evidence is provided that methionine-58 serves as an in-frame alternative translation site for holocarboxylase synthetase (HLCS58). → Full-length HLCS and HLCS58 enter the nucleus, but HLCS58 is the predominant variant. → HLCS58 has biological activity as biotin protein ligase. -- Abstract: Holocarboxylase synthetase (HLCS) catalyzes the covalent binding of biotin to both carboxylases in extranuclear structures and histones in cell nuclei, thereby mediating important roles in intermediary metabolism, gene regulation, and genome stability. HLCS has three putative translational start sites (methionine-1, -7, and -58), but lacks a strong nuclear localization sequence that would explain its participation in epigenetic events in the cell nucleus. Recent evidence suggests that small quantities of HLCS with a start site in methionine-58 (HLCS58) might be able to enter the nuclear compartment. We generated the following novel insights into HLCS biology. First, we generated a novel HLCS fusion protein vector to demonstrate that methionine-58 is a functional translation start site in human cells. Second, we used confocal microscopy and western blots to demonstrate that HLCS58 enters the cell nucleus in meaningful quantities, and that full-length HLCS localizes predominantly in the cytoplasm but may also enter the nucleus. Third, we produced recombinant HLCS58 to demonstrate its biological activity toward catalyzing the biotinylation of both carboxylases and histones. Collectively, these observations are consistent with roles of HLCS58 and full-length HLCS in nuclear events. We conclude this report by proposing a novel role for HLCS in epigenetic events, mediated by physical interactions between HLCS and other chromatin proteins as part of a larger multiprotein complex that mediates gene repression.

  19. OSCAR Is a Receptor for Surfactant Protein D That Activates TNF-α Release from Human CCR2+ Inflammatory Monocytes

    DEFF Research Database (Denmark)

    Barrow, Alexander D; Palarasah, Yaseelan; Bugatti, Mattia

    2015-01-01

    of recombinant SP-D and captured native SP-D from human bronchoalveolar lavage. OSCAR localized in an intracellular compartment of alveolar macrophages together with SP-D. Moreover, we found OSCAR on the surface of interstitial lung and blood CCR2(+) inflammatory monocytes, which secreted TNF-α when exposed...

  20. Arsenite induces apoptosis in human mesenchymal stem cells by altering Bcl-2 family proteins and by activating intrinsic pathway

    International Nuclear Information System (INIS)

    Yadav, Santosh; Shi Yongli; Wang Feng; Wang He

    2010-01-01

    Purpose: Environmental exposure to arsenic is an important public health issue. The effects of arsenic on different tissues and organs have been intensively studied. However, the effects of arsenic on bone marrow mesenchymal stem cells (MSCs) have not been reported. This study is designed to investigate the cell death process caused by arsenite and its related underlying mechanisms on MSCs. The rationale is that absorbed arsenic in the blood circulation can reach to the bone marrow and may affect the cell survival of MSCs. Methods: MSCs of passage 1 were purchased from Tulane University, grown till 70% confluency level and plated according to the experimental requirements followed by treatment with arsenite at various concentrations and time points. Arsenite (iAs III ) induced cytotoxic effects were confirmed by cell viability and cell cycle analysis. For the presence of canonic apoptosis markers; DNA damage, exposure of intramembrane phosphotidylserine, protein and m-RNA expression levels were analyzed. Results: iAs III induced growth inhibition, G2-M arrest and apoptotic cell death in MSCs, the apoptosis induced by iAs III in the cultured MSCs was, via altering Bcl-2 family proteins and by involving intrinsic pathway. Conclusion: iAs III can induce apoptosis in bone marrow-derived MSCs via Bcl-2 family proteins, regulating intrinsic apoptotic pathway. Due to the multipotency of MSC, acting as progenitor cells for a variety of connective tissues including bone, adipose, cartilage and muscle, these effects of arsenic may be important in assessing the health risk of the arsenic compounds and understanding the mechanisms of arsenic-induced harmful effects.

  1. Phorbol 12,13-dibutyrate-induced protein kinase C activation triggers sustained contracture in human myometrium in vitro.

    Science.gov (United States)

    Massenavette, Laurence; Paul, Wilène; Corriveau, Stéphanie; Pasquier, Jean-Charles; Rousseau, Éric

    2017-09-01

    Although physiologic transition from rhythmic contractions to uterine retraction postpartum remains a poorly understood process, it has been shown that the latter is essential in the prevention of hemorrhage and its negative consequences. To investigate the transition from oscillatory contractions to tonic contracture in human myometrium after delivery, a mechanism purported to facilitate postpartum hemostasis. Protein kinase C (PKC) plays a key regulatory role in human uterine contractions because it can prevent dephosphorylation of regulatory proteins and sensitize the contractile machinery to low Ca 2+ . Thus, activation of PKC by phorbol 12,13-dibutyrate (PDBu) may act as a strong uterotonic agent. Uterine biopsies were obtained from consenting women undergoing elective caesarian delivery at term without labor (N = 19). Isometric tension measurements were performed on uterine strips (n = 114). The amplitudes and area under the curve of phasic contractions and tonic responses were measured and compared. A total of 1 μM PDBu was added to the isolated organ baths, and maximal tension of the uterine contracture was determined in the absence and presence of either 1 μM of staurosporine, 100 nM nifedipine, or 10 μM cyclopiazonic acid to assess the role of PKC and calcium sensitivity on uterine contractility. On the addition of PDBu on either basal or oxytocin-induced activity, consistent contractures were obtained concomitant with complete inhibition of phasic contractions. After a 30-minute incubation period, the mean amplitude of the PDBu-induced tone represented 65.3% of the amplitude of spontaneous contraction. Staurosporine, a protein kinase inhibitor, induced a 91.9% inhibition of PDBu contractures, a process not affected by nifedipine or cyclopiazonic acid, thus indicating that this mechanism is largely Ca 2+ independent. Pharmacologic activation of PKC leads to a significant contracture of the myometrium. Together, these data suggest that the up

  2. Induction of glutathione synthesis in human hepatocytes by acute and chronic arsenic exposure: Differential roles of mitogen-activated protein kinases

    International Nuclear Information System (INIS)

    Hou, Yongyong; Wang, Yi; Wang, Huihui; Xu, Yuanyuan

    2014-01-01

    Highlights: • Arsenic exposure increased intracellular levels of glutathione. • Mitogen-activated protein kinases were involved in glutathione homeostasis. • ERK contributed to glutathione synthesis during acute arsenic exposure. • Glutathione synthesis was regulated by p38 at least in part independent of NRF2 during chronic arsenic exposure. - Abstract: Glutathione (GSH) is a vital component of antioxidant defense which protects cells from toxic insults. Previously we found intracellular GSH was involved in cell resistance against arsenic-induced cytotoxicity. However, molecular mechanisms of GSH homeostasis during arsenic exposure are largely undefined. Here, we investigated roles of mitogen-activated protein kinases (MAPKs) in GSH synthesis pathway with two arsenic exposure strategies by using Chang human hepatocytes. In one strategy, acute arsenic exposure (20 μM, 24 h) was applied, as MAPK signaling is generally considered to be transient. In the other one, chronic arsenic exposure (500 nM, 20 weeks) was applied, which mimicked the general human exposure to arsenic. We found that acute arsenic exposure activated extracellular signal-regulated 1/2 kinases (ERK1/2) and c-Jun N-terminal kinase (JNK) in parallel with increased transcription and nuclear translocation of factor-erythroid 2-related factor 2 (NRF2) and enhanced expression of γ-glutamyl cysteine ligase catalytic subunit (GCLC), resulting in elevated intracellular GSH levels. Specific ERK inhibitor abolished arsenic-induced NRF2 nuclear translocation and GSH synthesis. During chronic arsenic exposure which induced a malignant cellular phenotype, continuous p38 activation and NRF2 nuclear translocation were observed with enhanced GSH synthesis. Specific p38 inhibitor attenuated arsenic-enhanced GSH synthesis without changing NRF2 nuclear translocation. Taken together, our results indicate MAPK pathways play an important role in cellular GSH homeostasis in response to arsenic. However, the

  3. Expression of human papilloma virus type 16 E5 protein in amelanotic melanoma cells regulates endo-cellular pH and restores tyrosinase activity

    Directory of Open Access Journals (Sweden)

    Coccia Raffaella

    2009-01-01

    Full Text Available Abstract Background Melanin synthesis, the elective trait of melanocytes, is regulated by tyrosinase activity. In tyrosinase-positive amelanotic melanomas this rate limiting enzyme is inactive because of acidic endo-melanosomal pH. The E5 oncogene of the Human Papillomavirus Type 16 is a small transmembrane protein with a weak transforming activity and a role during the early steps of viral infections. E5 has been shown to interact with 16 kDa subunit C of the trans-membrane Vacuolar ATPase proton pump ultimately resulting in its functional suppressions. However, the cellular effects of such an interaction are still under debate. With this work we intended to explore whether the HPV16 E5 oncoprotein does indeed interact with the vacuolar ATPase proton pump once expressed in intact human cells and whether this interaction has functional consequences on cell metabolism and phenotype. Methods The expression of the HPV16-E5 oncoproteins was induced in two Tyrosinase-positive amelanotic melanomas (the cell lines FRM and M14 by a retroviral expression construct. Modulation of the intracellular pH was measured with Acridine orange and fluorescence microscopy. Expression of tyrosinase and its activity was followed by RT-PCR, Western Blot and enzyme assay. The anchorage-independence growth and the metabolic activity of E5 expressing cells were also monitored. Results We provide evidence that in the E5 expressing cells interaction between E5 and V-ATPase determines an increase of endo-cellular pH. The cellular alkalinisation in turn leads to the post-translational activation of tyrosinase, melanin synthesis and phenotype modulation. These effects are associated with an increased activation of tyrosine analogue anti-blastic drugs. Conclusion Once expressed within intact human cells the HPV16-E5 oncoprotein does actually interact with the vacuolar V-ATPase proton pump and this interaction induces a number of functional effects. In amelanotic melanomas these

  4. Cell-type specific DNA-protein interactions at the tissue-type plasminogen activator promoter in human endothelial and HeLa cells in vivo and in vitro

    NARCIS (Netherlands)

    Arts, J.; Herr, I.; Lansink, M.; Angel, P.; Kooistra, T.

    1997-01-01

    Tissue-type plasminogen activator (t-PA) gene expression in human endothelial cells and HeLa cells is stimulated by the protein kinase C activator phorbol 12-myristate 13-acetate (PMA) at the level of transcription. To study the mechanism of transcriptional regulation, we have characterized a

  5. Studies of the Interaction between Isoimperatorin and Human Serum Albumin by Multispectroscopic Method: Identification of Possible Binding Site of the Compound Using Esterase Activity of the Protein

    Directory of Open Access Journals (Sweden)

    Samira Ranjbar

    2013-01-01

    Full Text Available Isoimperatorin is one of the main components of Prangos ferulacea as a linear furanocoumarin and used as anti-inflammatory, analgesic, antispasmodic, and anticancer drug. Human serum albumin (HSA is a principal extracellular protein with a high concentration in blood plasma and carrier for many drugs to different molecular targets. Since the carrying of drug by HSA may affect on its structure and action, we decided to investigate the interaction between HSA and isoimperatorin using fluorescence and UV spectroscopy. Fluorescence data indicated that isoimperatorin quenches the intrinsic fluorescence of the HSA via a static mechanism and hydrophobic interaction play the major role in the drug binding. The binding average distance between isoimperatorin and Trp 214 of HSA was estimated on the basis of the theory of Förster energy transfer. Decrease of protein surface hydrophobicity (PSH was also documented upon isoimperatorin binding. Furthermore, the synchronous fluorescence spectra show that the microenvironment of the tryptophan residues does not have obvious changes. Site marker compettive and fluorescence experiments revealed that the binding of isoimperatorin to HSA occurred at or near site I. Finally, the binding details between isoimperatorin and HSA were further confirmed by molecular docking and esterase activity inhibition studies which revealed that drug was bound at subdomain IIA.

  6. Protective Effects of Ferulic Acid on High Glucose-Induced Protein Glycation, Lipid Peroxidation, and Membrane Ion Pump Activity in Human Erythrocytes.

    Directory of Open Access Journals (Sweden)

    Weerachat Sompong

    Full Text Available Ferulic acid (FA is the ubiquitous phytochemical phenolic derivative of cinnamic acid. Experimental studies in diabetic models demonstrate that FA possesses multiple mechanisms of action associated with anti-hyperglycemic activity. The mechanism by which FA prevents diabetes-associated vascular damages remains unknown. The aim of study was to investigate the protective effects of FA on protein glycation, lipid peroxidation, membrane ion pump activity, and phosphatidylserine exposure in high glucose-exposed human erythrocytes. Our results demonstrated that FA (10-100 μM significantly reduced the levels of glycated hemoglobin (HbA1c whereas 0.1-100 μM concentrations inhibited lipid peroxidation in erythrocytes exposed to 45 mM glucose. This was associated with increased glucose consumption. High glucose treatment also caused a significant reduction in Na+/K+-ATPase activity in the erythrocyte plasma membrane which could be reversed by FA. Furthermore, we found that FA (0.1-100 μM prevented high glucose-induced phosphatidylserine exposure. These findings provide insights into a novel mechanism of FA for the prevention of vascular dysfunction associated with diabetes.

  7. Immunoregulatory activities of human immunodeficiency virus (HIV) proteins: Effect of HIV recombinant and synthetic peptides on immunoglobulin synthesis and proliferative responses by normal lymphocytes

    International Nuclear Information System (INIS)

    Nair, M.P.N.; Pottathil, R.; Heimer, E.P.; Schwartz, S.A.

    1988-01-01

    Recombinant and synthetic peptides corresponding to envelope proteins of the human immunodeficiency virus (HIV) were examined for their effects on the activities of lymphocytes from normal donors in vitro. Although lymphocytes cultured with env-gag peptides produced significant amounts of IgG, addition of env-gag peptides to a pokeweed mitogen-induced B-cell activation system resulted in suppression of immunoglobulin synthesis by normal lymphocytes. Recombinant antigens, env-gag and env-80 dihydrofolate reductase (DHFR), produced a substantial proliferative response by peripheral blood mononuclear cells (PBMC) as determined by [ 3 H]thymidine incorporation. PBMC precultured with HIV synthetic peptide env 578-608 also manifested significant proliferative responses as compared to control cultures. CD3 + lymphocytes precultured with recombinant HIV antigens, env-gag and env-80 DHFR, and synthetic HIV peptide, env 487-511, showed moderate but significant proliferative responses. Both recombinant antigens and synthetic peptides also produced a dose-dependent stimulatory effect on proliferation by CD3 - lymphocytes. These studies demonstrate that recombinant and synthetic peptides of the HIV genome express immunoregulatory T- and B-cell epitopes. Identification of unique HIV epitopes with immunogenic and immunoregulatory activities is necessary for the development of an effective vaccine against HIV infection

  8. 3K3A-activated protein C stimulates postischemic neuronal repair by human neural stem cells in mice

    DEFF Research Database (Denmark)

    Wang, Yaoming; Zhao, Zhen; Rege, Sanket V

    2016-01-01

    -APC (Lys191-193Ala) mutant in which three Lys residues (KKK191-193) were replaced with alanine, and/or its other mutants with reduced (>90%) anticoagulant activity, engineered to reduce APC-associated bleeding risk while retaining normal cell-signaling activity, have shown benefits in preclinical models...... of ischemic stroke, brain trauma, multiple sclerosis, amyotrophic lateral sclerosis, sepsis, ischemic and reperfusion injury of heart, kidney and liver, pulmonary, kidney and gastrointestinal inflammation, diabetes and lethal body radiation. On the basis of proof-of-concept studies and an excellent safety...

  9. Autolytic activity of human calpain 7 is enhanced by ESCRT-III-related protein IST1 through MIT-MIM interaction.

    Science.gov (United States)

    Osako, Yohei; Maemoto, Yuki; Tanaka, Ryohei; Suzuki, Hironori; Shibata, Hideki; Maki, Masatoshi

    2010-11-01

    Calpain 7, a mammalian ortholog of yeast Cpl1/Rim13 and fungal PalB, is an atypical calpain that lacks a penta-EF-hand domain. Previously, we reported that a region containing a tandem repeat of microtubule-interacting and transport (MIT) domains in calpain 7 interacts with a subset of endosomal sorting complex required for transport (ESCRT)-III-related proteins, suggesting involvement of calpain 7 in the ESCRT system. Although yeast and fungal calpains are thought to be involved in alkaline adaptation via limited proteolysis of specific transcription factors, proteolytic activity of calpain 7 has not been demonstrated yet. In this study, we investigated the interaction between calpain 7 and a newly reported ESCRT-III family member, increased sodium tolerance-1 (IST1), which possesses two different types of MIT-interacting motifs (MIM1 and MIM2). We found that glutathione-S-transferase (GST)-fused tandem MIT domains of calpain 7 (calpain 7MIT) pulled down FLAG-tagged IST1 expressed in HEK293T cells. Coimmunoprecipitation assays with various deletion or point mutants of epitope-tagged calpain 7 and IST1 revealed that both repetitive MIT domains and MIMs are required for efficient interaction. Direct MIT-MIM binding was confirmed by a pulldown experiment with GST-fused IST1 MIM and purified recombinant calpain 7MIT. Furthermore, we found that the GST-MIM protein enhances the autolysis of purified Strep-tagged monomeric green fluorescent protein (mGFP)-fused calpain 7 (mGFP-calpain 7-Strep). The autolysis was almost completely abolished by 10 mmN-ethylmaleimide but only partially inhibited by 1 mm leupeptin or E-64. The putative catalytic Cys290-substituted mutant (mGFP-calpain 7(C290S)-Strep) showed no autolytic activity. These results demonstrate for the first time that human calpain 7 is proteolytically active, and imply that calpain 7 is activated in the ESCRT system. © 2010 The Authors Journal compilation © 2010 FEBS.

  10. Expression of the helix-loop-helix protein inhibitor of DNA binding-1 (ID-1) is activated by all-trans retinoic acid in normal human keratinocytes

    International Nuclear Information System (INIS)

    Villano, C.M.; White, L.A.

    2006-01-01

    The ID (inhibitor of differentiation or DNA binding) helix-loop-helix proteins are important mediators of cellular differentiation and proliferation in a variety of cell types through regulation of gene expression. Overexpression of the ID proteins in normal human keratinocytes results in extension of culture lifespan, indicating that these proteins are important for epidermal differentiation. Our hypothesis is that the ID proteins are targets of the retinoic acid signaling pathway in keratinocytes. Retinoids, vitamin A analogues, are powerful regulators of cell growth and differentiation and are widely used in the prevention and treatment of a variety of cancers in humans. Furthermore, retinoic acid is necessary for the maintenance of epithelial differentiation and demonstrates an inhibitory action on skin carcinogenesis. We examined the effect of all-trans retinoic acid on expression of ID-1, -2, -3, and -4 in normal human keratinocytes and found that exposure of these cells to all-trans retinoic acid causes an increase in both ID-1 and ID-3 gene expression. Furthermore, our data show that this increase is mediated by increased transcription involving several cis-acting elements in the distal portion of the promoter, including a CREB-binding site, an Egr1 element, and an YY1 site. These data demonstrate that the ID proteins are direct targets of the retinoic acid signaling pathway. Given the importance of the ID proteins to epidermal differentiation, these results suggest that IDs may be mediating some of the effects of all-trans retinoic acid in normal human keratinocytes

  11. A role for protein phosphatase-2A in p38 mitogen-activated protein kinase-mediated regulation of the c-Jun NH(2)-terminal kinase pathway in human neutrophils.

    Science.gov (United States)

    Avdi, Natalie J; Malcolm, Kenneth C; Nick, Jerry A; Worthen, G Scott

    2002-10-25

    Human neutrophil accumulation in inflammatory foci is essential for the effective control of microbial infections. Although exposure of neutrophils to cytokines such as tumor necrosis factor-alpha (TNFalpha), generated at sites of inflammation, leads to activation of MAPK pathways, mechanisms responsible for the fine regulation of specific MAPK modules remain unknown. We have previously demonstrated activation of a TNFalpha-mediated JNK pathway module, leading to apoptosis in adherent human neutrophils (Avdi, N. J., Nick, J. A., Whitlock, B. B., Billstrom, M. A., Henson, P. M., Johnson, G. L., and Worthen, G. S. (2001) J. Biol. Chem. 276, 2189-2199). Herein, evidence is presented linking regulation of the JNK pathway to p38 MAPK and the Ser/Thr protein phosphatase-2A (PP2A). Inhibition of p38 MAPK by SB 203580 and M 39 resulted in significant augmentation of TNFalpha-induced JNK and MKK4 (but not MKK7 or MEKK1) activation, whereas prior exposure to a p38-activating agent (platelet-activating factor) diminished the TNFalpha-induced JNK response. TNFalpha-induced apoptosis was also greatly enhanced upon p38 inhibition. Studies with a reconstituted cell-free system indicated the absence of a direct inhibitory effect of p38 MAPK on the JNK module. Neutrophil exposure to the Ser/Thr phosphatase inhibitors okadaic acid and calyculin A induced JNK activation. Increased phosphatase activity following TNFalpha stimulation was shown to be PP2A-associated and p38-dependent. Furthermore, PP2A-induced dephosphorylation of MKK4 resulted in its inactivation. Thus, in neutrophils, p38 MAPK, through a PP2A-mediated mechanism, regulates the JNK pathway, thus determining the extent and nature of subsequent responses such as apoptosis.

  12. Ser649 and Ser650 are the major determinants of protein kinase A-mediated activation of human hormone-sensitive lipase against lipid substrates

    DEFF Research Database (Denmark)

    Krintel, Christian; Osmark, Peter; Larsen, Martin Røssel

    2008-01-01

    Hormone-sensitive lipase (HSL) is a key enzyme in the mobilization of fatty acids from stored triacylglycerols. Its activity is regulated by reversible protein phosphorylation. In rat HSL Ser563, Ser659 and Ser660 have been shown to be phosphorylated by protein kinase A (PKA) in vitro as well...

  13. Trace elements and protein in human milk

    International Nuclear Information System (INIS)

    Abusamra, Y.I.H.

    1995-01-01

    The trace elements Zn, Fe, Cu, Mn, Ni and Pb and some related major elements which are Ca, Cl K and total protein contents of human samples from ninety mothers were examined in this study. Samples were collected from Khartoum, Khartoum North and Omdurman, from the second day of delivery up to the third month where the milk reaches a relatively stable levels. These samples representing different stages of lactation which are colostrum ( 1-3 days ), tranitional ( up to 14 days ) and mature milk. The principle aim of this study is to measure the trace elements and protein contents in relation to stage of lactation and to compare with the literature. Atomic absorption spectroscopy and X-ray fluorescence were used to measure trace elements in the samples. The methods were found to be quite reliable as proved by the analysis of the standard reference material HM-1. Whereas neutron activation analysis was used for measurements of total protein. Colostrum was found to have the highest amounts of trace elements and protein. Fe mean concentration was 273 g/dm 3 at colostrum stage and it decreased to 146 g/dm 3 in mature milk ( 49% ). Zn decreased from 6000 g/dm 3 in colostrum to 1300 g/dm 3 in mature stage ( 78% ). Mn was 12g/dm 3 in colostrum, and it decreased to 2.9 g/dm 3 in mature milk ( 75% ). Cu decreased from 370 g/dm 3 to 117 g/dm 3 ( 68% ). Ni decreased from 24 g/dm 3 to 8.8 g/dm 3 ( 63% ) and Pb from 12 g/dm 3 to 2.6 g/dm 3 ( 76% ). Total protein was 37.3% of the dry milk in colostrum and it was 12.2% in mature milk. (author). 75 refs., 25 tabs., 30 figs

  14. Intron-exon organization of the active human protein S gene PS. alpha. and its pseudogene PS. beta. : Duplication and silencing during primate evolution

    Energy Technology Data Exchange (ETDEWEB)

    Ploos van Amstel, H.; Reitsma, P.H.; van der Logt, C.P.; Bertina, R.M. (University Hospital, Leiden (Netherlands))

    1990-08-28

    The human protein S locus on chromosome 3 consists of two protein S genes, PS{alpha} and PS{beta}. Here the authors report the cloning and characterization of both genes. Fifteen exons of the PS{alpha} gene were identified that together code for protein S mRNA as derived from the reported protein S cDNAs. Analysis by primer extension of liver protein S mRNA, however, reveals the presence of two mRNA forms that differ in the length of their 5{prime}-noncoding region. Both transcripts contain a 5{prime}-noncoding region longer than found in the protein S cDNAs. The two products may arise from alternative splicing of an additional intron in this region or from the usage of two start sites for transcription. The intron-exon organization of the PS{alpha} gene fully supports the hypothesis that the protein S gene is the product of an evolutional assembling process in which gene modules coding for structural/functional protein units also found in other coagulation proteins have been put upstream of the ancestral gene of a steroid hormone binding protein. The PS{beta} gene is identified as a pseudogene. It contains a large variety of detrimental aberrations, viz., the absence of exon I, a splice site mutation, three stop codons, and a frame shift mutation. Overall the two genes PS{alpha} and PS{beta} show between their exonic sequences 96.5% homology. Southern analysis of primate DNA showed that the duplication of the ancestral protein S gene has occurred after the branching of the orangutan from the African apes. A nonsense mutation that is present in the pseudogene of man also could be identified in one of the two protein S genes of both chimpanzee and gorilla. This implicates that silencing of one of the two protein S genes must have taken place before the divergence of the three African apes.

  15. Spectroscopic study of drug-binding characteristics of unmodified and pNPA-based acetylated human serum albumin: Does esterase activity affect microenvironment of drug binding sites on the protein?

    Energy Technology Data Exchange (ETDEWEB)

    Moradi, Nastaran [Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Faculty of Pharmaceutical Sciences, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Ashrafi-Kooshk, Mohammad Reza [Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Ghobadi, Sirous [Department of Biology, Faculty of Sciences, Razi University, Kermanshah (Iran, Islamic Republic of); Shahlaei, Mohsen [Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Faculty of Pharmaceutical Sciences, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Khodarahmi, Reza, E-mail: rkhodarahmi@mbrc.ac.ir [Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Faculty of Pharmaceutical Sciences, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of)

    2015-04-15

    Human serum albumin (HSA) is the most prominent extracellular protein in blood plasma. There are several binding sites on the protein which provide accommodation for structurally-unrelated endogenous and exogenous ligands and a wide variety of drugs. “Esterase-like” activity (hydrolysis of p-nitrophenyl esters) by the protein has been also reported. In the current study, we set out to investigate the interaction of indomethacin and ibuprofen with the unmodified and modified HSA (pNPA-modified HSA) using various spectroscopic techniques. Fluorescence data showed that 1:1 binding of drug to HSA is associated with quenching of the protein intrinsic fluorescence. Decrease of protein surface hydrophobicity (PSH), alteration in drug binding affinity and change of the protein stability, after esterase-like activity and permanent acetylation of HSA, were also documented. Analysis of the quenching and thermodynamic parameters indicated that forces involved in drug–HSA interactions change upon the protein modification. - Highlights: • Binding propensity of indomethacin extremely decreased upon the protein acetylation. • There is no ibuprofen binding after protein acetylation. • Protein stability changes upon drug binding as well as protein acetylation. • Drug pharmacokinetics may be influenced under co-administration of HSA-modifier drugs.

  16. Spectroscopic study of drug-binding characteristics of unmodified and pNPA-based acetylated human serum albumin: Does esterase activity affect microenvironment of drug binding sites on the protein?

    International Nuclear Information System (INIS)

    Moradi, Nastaran; Ashrafi-Kooshk, Mohammad Reza; Ghobadi, Sirous; Shahlaei, Mohsen; Khodarahmi, Reza

    2015-01-01

    Human serum albumin (HSA) is the most prominent extracellular protein in blood plasma. There are several binding sites on the protein which provide accommodation for structurally-unrelated endogenous and exogenous ligands and a wide variety of drugs. “Esterase-like” activity (hydrolysis of p-nitrophenyl esters) by the protein has been also reported. In the current study, we set out to investigate the interaction of indomethacin and ibuprofen with the unmodified and modified HSA (pNPA-modified HSA) using various spectroscopic techniques. Fluorescence data showed that 1:1 binding of drug to HSA is associated with quenching of the protein intrinsic fluorescence. Decrease of protein surface hydrophobicity (PSH), alteration in drug binding affinity and change of the protein stability, after esterase-like activity and permanent acetylation of HSA, were also documented. Analysis of the quenching and thermodynamic parameters indicated that forces involved in drug–HSA interactions change upon the protein modification. - Highlights: • Binding propensity of indomethacin extremely decreased upon the protein acetylation. • There is no ibuprofen binding after protein acetylation. • Protein stability changes upon drug binding as well as protein acetylation. • Drug pharmacokinetics may be influenced under co-administration of HSA-modifier drugs

  17. Pharmacological Inhibition of Protein Kinase G1 Enhances Bone Formation by Human Skeletal Stem Cells Through Activation of RhoA-Akt Signaling

    DEFF Research Database (Denmark)

    Kermani, Abbas Jafari; Siersbaek, Majken S; Chen, Li

    2015-01-01

    for several malignant and nonmalignant conditions. We screened a library of kinase inhibitors to identify small molecules that enhance bone formation by human skeletal (stromal or mesenchymal) stem cells (hMSC). We identified H-8 (known to inhibit protein kinases A, C, and G) as a potent enhancer of ex vivo......Development of novel approaches to enhance bone regeneration is needed for efficient treatment of bone defects. Protein kinases play a key role in regulation of intracellular signal transduction pathways, and pharmacological targeting of protein kinases has led to development of novel treatments...

  18. INHIBITION OF THE DNA-BINDING ACTIVITY OF DROSOPHILA SUPPRESSOR OF HAIRLESS AND OF ITS HUMAN HOMOLOG, KBF2/RBP-J-KAPPA, BY DIRECT PROTEIN-PROTEIN INTERACTION WITH DROSOPHILA HAIRLESS

    NARCIS (Netherlands)

    BROU, C; LOGEAT, F; LECOURTOIS, M; VANDEKERCKHOVE, Joël; KOURILSKY, P; SCHWEISGUTH, F; ISRAEL, A

    1994-01-01

    We have purified the sequence-specific DNA-binding protein KBF2 and cloned the corresponding cDNA, which is derived from the previously described RBP-J kappa gene, the human homolog of the Drosophila Suppressor of Hairless [Su(H)] gene. Deletion studies of the RBP-J kappa and Su(H) proteins allowed

  19. Up-regulation of glutathione-related genes, enzyme activities and transport proteins in human cervical cancer cells treated with doxorubicin.

    Science.gov (United States)

    Drozd, Ewa; Krzysztoń-Russjan, Jolanta; Marczewska, Jadwiga; Drozd, Janina; Bubko, Irena; Bielak, Magda; Lubelska, Katarzyna; Wiktorska, Katarzyna; Chilmonczyk, Zdzisław; Anuszewska, Elżbieta; Gruber-Bzura, Beata

    2016-10-01

    Doxorubicin (DOX), one of the most effective anticancer drugs, acts in a variety of ways including DNA damage, enzyme inhibition and generation of reactive oxygen species. Glutathione (GSH) and glutathione-related enzymes including: glutathione peroxidase (GPX), glutathione reductase (GSR) and glutathione S-transferases (GST) may play a role in adaptive detoxification processes in response to the oxidative stress, thus contributing to drug resistance phenotype. In this study, we investigated effects of DOX treatment on expression and activity of GSH-related enzymes and multidrug resistance-associated proteins in cultured human cervical cancer cells displaying different resistance against this drug (HeLa and KB-V1). Determination of expression level of genes encoding GST isoforms and MRP proteins (GCS, GPX, GSR, GSTA1-3, GSTM1, GSTP1, ABCC1-3, MGST1-3) was performed using StellARray™ Technology. Enzymatic activities of GPX and GSR were measured using biochemical methods. Expression of MRP1 was examined by immunofluorescence microscopy. This study showed that native expression levels of GSTM1 and GSTA3 were markedly higher in KB-V1 cells (2000-fold and 200-fold) compared to HeLa cells. Resistant cells have also shown significantly elevated expression of GSTA1 and GSTA2 genes (200-fold and 50-fold) as a result of DOX treatment. In HeLa cells, exposure to DOX increased expression of all genes: GSTM1 (7-fold) and GSTA1-3 (550-fold, 150-fold and 300-fold). Exposure to DOX led to the slight increase of GCS expression as well as GPX activity in KB-V1 cells, while in HeLa cells it did not. Expression of ABCC1 (MRP1) was not increased in any of the tested cell lines. Our results indicate that expression of GSTM1 and GSTA1-3 genes is up-regulated by DOX treatment and suggest that activity of these genes may be associated with drug resistance of the tested cells. At the same time, involvement of MRP1 in DOX resistance in the given experimental conditions is unlikely

  20. Human cancer protein-protein interaction network: a structural perspective.

    Directory of Open Access Journals (Sweden)

    Gozde Kar

    2009-12-01

    Full Text Available Protein-protein interaction networks provide a global picture of cellular function and biological processes. Some proteins act as hub proteins, highly connected to others, whereas some others have few interactions. The dysfunction of some interactions causes many diseases, including cancer. Proteins interact through their interfaces. Therefore, studying the interface properties of cancer-related proteins will help explain their role in the interaction networks. Similar or overlapping binding sites should be used repeatedly in single interface hub proteins, making them promiscuous. Alternatively, multi-interface hub proteins make use of several distinct binding sites to bind to different partners. We propose a methodology to integrate protein interfaces into cancer interaction networks (ciSPIN, cancer structural protein interface network. The interactions in the human protein interaction network are replaced by interfaces, coming from either known or predicted complexes. We provide a detailed analysis of cancer related human protein-protein interfaces and the topological properties of the cancer network. The results reveal that cancer-related proteins have smaller, more planar, more charged and less hydrophobic binding sites than non-cancer proteins, which may indicate low affinity and high specificity of the cancer-related interactions. We also classified the genes in ciSPIN according to phenotypes. Within phenotypes, for breast cancer, colorectal cancer and leukemia, interface properties were found to be discriminating from non-cancer interfaces with an accuracy of 71%, 67%, 61%, respectively. In addition, cancer-related proteins tend to interact with their partners through distinct interfaces, corresponding mostly to multi-interface hubs, which comprise 56% of cancer-related proteins, and constituting the nodes with higher essentiality in the network (76%. We illustrate the interface related affinity properties of two cancer-related hub

  1. The Effect of a p38 Mitogen-Activated Protein Kinase Inhibitor on Cellular Senescence of Cultivated Human Corneal Endothelial Cells.

    Science.gov (United States)

    Hongo, Akane; Okumura, Naoki; Nakahara, Makiko; Kay, EunDuck P; Koizumi, Noriko

    2017-07-01

    We have begun a clinical trial of a cell-based therapy for corneal endothelial dysfunction in Japan. The purpose of this study was to investigate the usefulness of a p38 MAPK inhibitor for prevention cellular senescence in cultivated human corneal endothelial cells (HCECs). HCECs of 10 donor corneas were divided and cultured with or without SB203580 (a p38 MAPK inhibitor). Cell density and morphology were evaluated by phase-contrast microscopy. Expression of function-related proteins was examined by immunofluorescent staining. Cellular senescence was evaluated by SA-β-gal staining and Western blotting for p16 and p21. Senescence-associated factors were evaluated by membrane blotting array, quantitative PCR, and ELISA. Phase-contrast microscopy showed a significantly higher cell density for HCECs cultured with SB203580 than without SB203580 (2623 ± 657 cells/mm2 and 1752 ± 628 cells/mm2, respectively). The HCECs cultured with SB203580 maintained a hexagonal morphology and expressed ZO-1, N-cadherin, and Na+/K+-ATPase in the plasma membrane, whereas the control HCECs showed an altered staining pattern for these marker proteins. HCECs cultured without SB203580 showed high positive SA-β-gal staining, a low nuclear/cytoplasm ratio, and expression of p16 and p21. IL-6, IL-8, CCL2, and CXCL1 were observed at high levels in low cell density HCECs cultured without SB203580. Activation of p38 MAPK signaling due to culture stress might be a causative factor that induces cellular senescence; therefore, the use of p38 MAPK inhibitor to counteract senescence may achieve sufficient numbers of HCECs for tissue engineering therapy for corneal endothelial dysfunction.

  2. Protein Misfolding and Human Disease

    DEFF Research Database (Denmark)

    Gregersen, Niels; Bross, Peter Gerd; Vang, Søren

    2006-01-01

    phenylketonuria, Parkinson's disease, α-1-antitrypsin deficiency, familial neurohypophyseal diabetes insipidus, and short-chain acyl-CoA dehydrogenase deficiency. Despite the differences, an emerging paradigm suggests that the cellular effects of protein misfolding provide a common framework that may contribute...

  3. A Novel Initiation Mechanism of Death in Streptococcus pneumoniae Induced by the Human Milk Protein-Lipid Complex HAMLET and Activated during Physiological Death*

    Science.gov (United States)

    Clementi, Emily A.; Marks, Laura R.; Duffey, Michael E.; Hakansson, Anders P.

    2012-01-01

    To cause colonization or infection, most bacteria grow in biofilms where differentiation and death of subpopulations is critical for optimal survival of the whole population. However, little is known about initiation of bacterial death under physiological conditions. Membrane depolarization has been suggested, but never shown to be involved, due to the difficulty of performing such studies in bacteria and the paucity of information that exists regarding ion transport mechanisms in prokaryotes. In this study, we performed the first extensive investigation of ion transport and membrane depolarization in a bacterial system. We found that HAMLET, a human milk protein-lipid complex, kills Streptococcus pneumoniae (the pneumococcus) in a manner that shares features with activation of physiological death from starvation. Addition of HAMLET to pneumococci dissipated membrane polarity, but depolarization per se was not enough to trigger death. Rather, both HAMLET- and starvation-induced death of pneumococci specifically required a sodium-dependent calcium influx, as shown using calcium and sodium transport inhibitors. This mechanism was verified under low sodium conditions, and in the presence of ionomycin or monensin, which enhanced pneumococcal sensitivity to HAMLET- and starvation-induced death. Pneumococcal death was also inhibited by kinase inhibitors, and indicated the involvement of Ser/Thr kinases in these processes. The importance of this activation mechanism was made evident, as dysregulation and manipulation of physiological death was detrimental to biofilm formation, a hallmark of bacterial colonization. Overall, our findings provide novel information on the role of ion transport during bacterial death, with the potential to uncover future antimicrobial targets. PMID:22700972

  4. A novel initiation mechanism of death in Streptococcus pneumoniae induced by the human milk protein-lipid complex HAMLET and activated during physiological death.

    Science.gov (United States)

    Clementi, Emily A; Marks, Laura R; Duffey, Michael E; Hakansson, Anders P

    2012-08-03

    To cause colonization or infection, most bacteria grow in biofilms where differentiation and death of subpopulations is critical for optimal survival of the whole population. However, little is known about initiation of bacterial death under physiological conditions. Membrane depolarization has been suggested, but never shown to be involved, due to the difficulty of performing such studies in bacteria and the paucity of information that exists regarding ion transport mechanisms in prokaryotes. In this study, we performed the first extensive investigation of ion transport and membrane depolarization in a bacterial system. We found that HAMLET, a human milk protein-lipid complex, kills Streptococcus pneumoniae (the pneumococcus) in a manner that shares features with activation of physiological death from starvation. Addition of HAMLET to pneumococci dissipated membrane polarity, but depolarization per se was not enough to trigger death. Rather, both HAMLET- and starvation-induced death of pneumococci specifically required a sodium-dependent calcium influx, as shown using calcium and sodium transport inhibitors. This mechanism was verified under low sodium conditions, and in the presence of ionomycin or monensin, which enhanced pneumococcal sensitivity to HAMLET- and starvation-induced death. Pneumococcal death was also inhibited by kinase inhibitors, and indicated the involvement of Ser/Thr kinases in these processes. The importance of this activation mechanism was made evident, as dysregulation and manipulation of physiological death was detrimental to biofilm formation, a hallmark of bacterial colonization. Overall, our findings provide novel information on the role of ion transport during bacterial death, with the potential to uncover future antimicrobial targets.

  5. Inferring high-confidence human protein-protein interactions

    Directory of Open Access Journals (Sweden)

    Yu Xueping

    2012-05-01

    Full Text Available Abstract Background As numerous experimental factors drive the acquisition, identification, and interpretation of protein-protein interactions (PPIs, aggregated assemblies of human PPI data invariably contain experiment-dependent noise. Ascertaining the reliability of PPIs collected from these diverse studies and scoring them to infer high-confidence networks is a non-trivial task. Moreover, a large number of PPIs share the same number of reported occurrences, making it impossible to distinguish the reliability of these PPIs and rank-order them. For example, for the data analyzed here, we found that the majority (>83% of currently available human PPIs have been reported only once. Results In this work, we proposed an unsupervised statistical approach to score a set of diverse, experimentally identified PPIs from nine primary databases to create subsets of high-confidence human PPI networks. We evaluated this ranking method by comparing it with other methods and assessing their ability to retrieve protein associations from a number of diverse and independent reference sets. These reference sets contain known biological data that are either directly or indirectly linked to interactions between proteins. We quantified the average effect of using ranked protein interaction data to retrieve this information and showed that, when compared to randomly ranked interaction data sets, the proposed method created a larger enrichment (~134% than either ranking based on the hypergeometric test (~109% or occurrence ranking (~46%. Conclusions From our evaluations, it was clear that ranked interactions were always of value because higher-ranked PPIs had a higher likelihood of retrieving high-confidence experimental data. Reducing the noise inherent in aggregated experimental PPIs via our ranking scheme further increased the accuracy and enrichment of PPIs derived from a number of biologically relevant data sets. These results suggest that using our high

  6. Compact conformations of human protein disulfide isomerase.

    Directory of Open Access Journals (Sweden)

    Shang Yang

    Full Text Available Protein disulfide isomerase (PDI composed of four thioredoxin-like domains a, b, b', and a', is a key enzyme catalyzing oxidative protein folding in the endoplasmic reticulum. Large scale molecular dynamics simulations starting from the crystal structures of human PDI (hPDI in the oxidized and reduced states were performed. The results indicate that hPDI adopts more compact conformations in solution than in the crystal structures, which are stabilized primarily by inter-domain interactions, including the salt bridges between domains a and b' observed for the first time. A prominent feature of the compact conformations is that the two catalytic domains a and a' can locate close enough for intra-molecular electron transfer, which was confirmed by the characterization of an intermediate with a disulfide between the two domains. Mutations, which disrupt the inter-domain interactions, lead to decreased reductase activity of hPDI. Our molecular dynamics simulations and biochemical experiments reveal the intrinsic conformational dynamics of hPDI and its biological impact.

  7. Development of a dual luciferase activity and fluorescamine protein assay adapted to a 384 micro-well plate format: Reducing variability in human luciferase transactivation cell lines aimed at endocrine active substances

    Science.gov (United States)

    Brennan, Jennifer; Tillitt, Donald E.

    2018-01-01

    There is a need to adapt cell bioassays to 384-well and 1536-well formats instead of the traditional 96-well format as high-throughput screening (HTS) demands increase. However, the sensitivity and performance of the bioassay must be re-verified in these higher micro-well plates, and verification of cell health must also be HT (high-throughput). We have adapted two commonly used human breast luciferase transactivation cell bioassays, the recently re-named estrogen agonist/antagonist screening VM7Luc4E2 cell bioassay (previously designated BG1Luc4E2) and the androgen/glucocorticoid screening MDA-kb2 cell bioassay, to 384-well formats for HTS of endocrine-active substances (EASs). This cost-saving adaptation includes a fast, accurate, and easy measurement of protein amount in each well via the fluorescamine assay with which to normalize luciferase activity of cell lysates without requiring any transfer of the cell lysates. Here we demonstrate that by accounting for protein amount in the cell lysates, antagonistic agents can easily be distinguished from cytotoxic agents in the MDA-kb2 and VM7Luc4E2 cell bioassays. Additionally, we demonstrate via the fluorescamine assay improved interpretation of luciferase activity in wells along the edge of the plate (the so-called “edge effect”), thereby increasing usable wells to the entire plate, not just interior wells.

  8. The effect of Walterinnesia aegyptia venom proteins on TCA cycle activity and mitochondrial NAD(+)-redox state in cultured human fibroblasts.

    Science.gov (United States)

    Ghneim, Hazem K; Al-Sheikh, Yazeed A; Aboul-Soud, Mourad A M

    2015-01-01

    Fibroblast cultures were used to study the effects of crude Walterinnesia aegyptia venom and its F1-F7 protein fractions on TCA cycle enzyme activities and mitochondrial NAD-redox state. Confluent cells were incubated with 10 μg of venom proteins for 4 hours at 37°C. The activities of all studied TCA enzymes and the non-TCA mitochondrial NADP(+)-dependent isocitrate dehydrogenase underwent significant reductions of similar magnitude (50-60% of control activity) upon incubation of cells with the crude venom and fractions F4, F5, and F7 and 60-70% for fractions F3 and F6. In addition, the crude and fractions F3-F7 venom proteins caused a drop in mitochondrial NAD(+) and NADP(+) levels equivalent to around 25% of control values. Whereas the crude and fractions F4, F5, and F7 venom proteins caused similar magnitude drops in NADH and NADPH (around 55% of control levels), fractions F3 and F6 caused a more drastic drop (60-70% of control levels) of both reduced coenzymes. Results indicate that the effects of venom proteins could be directed at the mitochondrial level and/or the rates of NAD(+) and NADP(+) biosynthesis.

  9. Bioactive glass induced osteogenic differentiation of human adipose stem cells is dependent on cell attachment mechanism and mitogen-activated protein kinases

    Directory of Open Access Journals (Sweden)

    M Ojansivu

    2018-02-01

    Full Text Available Bioactive glasses (BaGs are widely utilised in bone tissue engineering (TE but the molecular response of cells to BaGs is poorly understood. To elucidate the mechanisms of cell attachment to BaGs and BaG-induced early osteogenic differentiation, we cultured human adipose stem cells (hASCs on discs of two silica-based BaGs S53P4 (23.0 Na2O - 20.0 CaO - 4.0 P2O5 - 53.0 SiO2 (wt-% and 1-06 (5.9 Na2O - 12.0 K2O - 5.3 MgO - 22.6 CaO - 4.0 P2O5 - 0.2 B2O3 - 50.0 SiO2 in the absence of osteogenic supplements. Both BaGs induced early osteogenic differentiation by increasing alkaline phosphatase activity (ALP and the expression of osteogenic marker genes RUNX2a and OSTERIX. Based on ALP activity, the slower reacting 1-06 glass was a stronger osteoinducer. Regarding the cell attachment, cells cultured on BaGs had enhanced integrinβ1 and vinculin production, and mature focal adhesions were smaller but more dispersed than on cell culture plastic (polystyrene. Focal adhesion kinase (FAK, extracellular signal-regulated kinase (ERK1/2 and c-Jun N-terminal kinase (JNK-induced c-Jun phosphorylations were upregulated by glass contact. Moreover, the BaG-stimulated osteoinduction was significantly reduced by FAK and mitogen-activated protein kinase (MAPK inhibitors, indicating an important role for FAK and MAPKs in the BaG-induced early osteogenic commitment of hASCs. Upon indirect insert culture, the ions released from the BaG discs could not reproduce the observed cellular changes, which highlighted the role of direct cell-BaG interactions in the osteopotential of BaGs. These findings gave valuable insight into the mechanism of BaG-induced osteogenic differentiation and therefore provided knowledge to aid the future design of new functional biomaterials to meet the increasing demand for clinical bone TE treatments.

  10. Function of the cytoplasmic tail of human calcitonin receptor-like receptor in complex with receptor activity-modifying protein 2

    Energy Technology Data Exchange (ETDEWEB)

    Kuwasako, Kenji, E-mail: kuwasako@fc.miyazaki-u.ac.jp [Frontier Science Research Center, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692 (Japan); Kitamura, Kazuo; Nagata, Sayaka; Hikosaka, Tomomi [Division of Circulation and Body Fluid Regulation, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692 (Japan); Kato, Johji [Frontier Science Research Center, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692 (Japan)

    2010-02-12

    Receptor activity-modifying protein 2 (RAMP2) enables calcitonin receptor-like receptor (CRLR) to form an adrenomedullin (AM)-specific receptor. Here we investigated the function of the cytoplasmic C-terminal tail (C-tail) of human (h)CRLR by co-transfecting its C-terminal mutants into HEK-293 cells stably expressing hRAMP2. Deleting the C-tail from CRLR disrupted AM-evoked cAMP production or receptor internalization, but did not affect [{sup 125}I]AM binding. We found that CRLR residues 428-439 are required for AM-evoked cAMP production, though deleting this region had little effect on receptor internalization. Moreover, pretreatment with pertussis toxin (100 ng/mL) led to significant increases in AM-induced cAMP production via wild-type CRLR/RAMP2 complexes. This effect was canceled by deleting CRLR residues 454-457, suggesting Gi couples to this region. Flow cytometric analysis revealed that CRLR truncation mutants lacking residues in the Ser/Thr-rich region extending from Ser{sup 449} to Ser{sup 467} were unable to undergo AM-induced receptor internalization and, in contrast to the effect on wild-type CRLR, overexpression of GPCR kinases-2, -3 and -4 failed to promote internalization of CRLR mutants lacking residues 449-467. Thus, the hCRLR C-tail is crucial for AM-evoked cAMP production and internalization of the CRLR/RAMP2, while the receptor internalization is dependent on the aforementioned GPCR kinases, but not Gs coupling.

  11. The potent activation of Ca(2+)-activated K(+) current by NVP-AUY922 in the human pancreatic duct cell line (PANC-1) possibly independent of heat shock protein 90 inhibition.

    Science.gov (United States)

    Chiang, Nai-Jung; Wu, Sheng-Nan; Chen, Li-Tzong

    2015-04-01

    NVP-AUY922 (AUY) is a potent inhibitor of heat shock protein 90 (HSP90). Whether this compound can exert additional effects on membrane ion channels remains elusive. We investigated the effect of AUY on ion currents in human pancreatic duct epithelial cells (PDECs), including PANC-1 and MIA PaCa-2. AUY increased the amplitude of the K(+) current (IK) in PANC-1 cells shown by whole-cell configuration. Single-channel recordings revealed a large-conductance Ca(2+)-activated K(+) (BKCa) channel in PANC-1, but not in MIA PaCa-2. In cell-attached mode, AUY increased the probability of BKCa channel opening and also potentiated the activity of stretch-induced channels. However, other HSP inhibitors, 17-AAG or BIIB021 only slightly increased the activity of BKCa channels. In inside-out recordings, sodium hydrosulphide or caffeic acid phenethyl ester increased the activity of BKCa channels, but AUY did not. We further evaluated whether conductance of Ca(2+)-activated K(+) channels (IK(Ca)) influenced secretion of HCO3(-) and fluid in PDECs by using a modified Whitcomb-Ermentrout model. Simulation studies showed that an increase in IK(Ca) resulted in additional secretion of HCO3(-) and fluid by mimicking the effect of AUY in PDECs. Collectively, AUY can interact with the BKCa channel to largely increase IK(Ca) in PDECs. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  12. The human protein disulfide isomerase gene family

    Directory of Open Access Journals (Sweden)

    Galligan James J

    2012-07-01

    Full Text Available Abstract Enzyme-mediated disulfide bond formation is a highly conserved process affecting over one-third of all eukaryotic proteins. The enzymes primarily responsible for facilitating thiol-disulfide exchange are members of an expanding family of proteins known as protein disulfide isomerases (PDIs. These proteins are part of a larger superfamily of proteins known as the thioredoxin protein family (TRX. As members of the PDI family of proteins, all proteins contain a TRX-like structural domain and are predominantly expressed in the endoplasmic reticulum. Subcellular localization and the presence of a TRX domain, however, comprise the short list of distinguishing features required for gene family classification. To date, the PDI gene family contains 21 members, varying in domain composition, molecular weight, tissue expression, and cellular processing. Given their vital role in protein-folding, loss of PDI activity has been associated with the pathogenesis of numerous disease states, most commonly related to the unfolded protein response (UPR. Over the past decade, UPR has become a very attractive therapeutic target for multiple pathologies including Alzheimer disease, Parkinson disease, alcoholic and non-alcoholic liver disease, and type-2 diabetes. Understanding the mechanisms of protein-folding, specifically thiol-disulfide exchange, may lead to development of a novel class of therapeutics that would help alleviate a wide range of diseases by targeting the UPR.

  13. Interaction of human biliverdin reductase with Akt/protein kinase B and phosphatidylinositol-dependent kinase 1 regulates glycogen synthase kinase 3 activity: a novel mechanism of Akt activation.

    Science.gov (United States)

    Miralem, Tihomir; Lerner-Marmarosh, Nicole; Gibbs, Peter E M; Jenkins, Jermaine L; Heimiller, Chelsea; Maines, Mahin D

    2016-08-01

    -Marmarosh, N., Gibbs, P. E. M., Jenkins, J. L., Heimiller, C., Maines, M. D. Interaction of human biliverdin reductase with Akt/protein kinase B and phosphatidylinositol-dependent kinase 1 regulates glycogen synthase kinase 3 activity: a novel mechanism of Akt activation. © FASEB.

  14. Fluorogen-activating proteins: beyond classical fluorescent proteins

    Directory of Open Access Journals (Sweden)

    Shengnan Xu

    2018-05-01

    Full Text Available Fluorescence imaging is a powerful technique for the real-time noninvasive monitoring of protein dynamics. Recently, fluorogen activating proteins (FAPs/fluorogen probes for protein imaging were developed. Unlike the traditional fluorescent proteins (FPs, FAPs do not fluoresce unless bound to their specific small-molecule fluorogens. When using FAPs/fluorogen probes, a washing step is not required for the removal of free probes from the cells, thus allowing rapid and specific detection of proteins in living cells with high signal-to-noise ratio. Furthermore, with different fluorogens, living cell multi-color proteins labeling system was developed. In this review, we describe about the discovery of FAPs, the design strategy of FAP fluorogens, the application of the FAP technology and the advances of FAP technology in protein labeling systems. KEY WORDS: Fluorogen activating proteins, Fluorogens, Genetically encoded sensors, Fluorescence imaging, Molecular imaging

  15. Gc protein (vitamin D-binding protein): Gc genotyping and GcMAF precursor activity.

    Science.gov (United States)

    Nagasawa, Hideko; Uto, Yoshihiro; Sasaki, Hideyuki; Okamura, Natsuko; Murakami, Aya; Kubo, Shinichi; Kirk, Kenneth L; Hori, Hitoshi

    2005-01-01

    The Gc protein (human group-specific component (Gc), a vitamin D-binding protein or Gc globulin), has important physiological functions that include involvement in vitamin D transport and storage, scavenging of extracellular G-actin, enhancement of the chemotactic activity of C5a for neutrophils in inflammation and macrophage activation (mediated by a GalNAc-modified Gc protein (GcMAF)). In this review, the structure and function of the Gc protein is focused on especially with regard to Gc genotyping and GcMAF precursor activity. A discussion of the research strategy "GcMAF as a target for drug discovery" is included, based on our own research.

  16. Novel Mechanism of Attenuation of LPS-Induced NF-κB Activation by the Heat Shock Protein 90 Inhibitor, 17-N-allylamino-17-demethoxygeldanamycin, in Human Lung Microvascular Endothelial Cells

    Science.gov (United States)

    Thangjam, Gagan S.; Dimitropoulou, Chistiana; Joshi, Atul D.; Barabutis, Nektarios; Shaw, Mary C.; Kovalenkov, Yevgeniy; Wallace, Chistopher M.; Fulton, David J.; Patel, Vijay

    2014-01-01

    Heat shock protein (hsp) 90 inhibition attenuates NF-κB activation and blocks inflammation. However, the precise mechanism of NF-κB regulation by hsp90 in the endothelium is not clear. We investigated the mechanisms of hsp90 inhibition by 17-N-allylamino-17-demethoxygeldanamycin (17-AAG) on NF-κB activation by LPS in primary human lung microvascular endothelial cells. Transcriptional activation of NF-κB was measured by luciferase reporter assay, gene expression by real-time RT-PCR, DNA binding of transcription factors by chromatin immunoprecipitation assay, protein–protein interaction by coimmunoprecipitation/immunoblotting, histone deacetylase (HDAC)/histone acetyltransferase enzyme activity by fluorometry, and nucleosome eviction by partial microccocal DNase digestion. In human lung microvascular endothelial cells, 17-AAG–induced degradation of IKBα was accomplished regardless of the phosphorylation/ubiquitination state of the protein. Hence, 17-AAG did not block LPS-induced NF-κB nuclear translocation and DNA binding activity. Instead, 17-AAG blocked the recruitment of the coactivator, cAMP response element binding protein binding protein, and prevented the assembly of a transcriptionally competent RNA polymerase II complex at the κB elements of the IKBα (an NF-κB–responsive gene) promoter. The effect of LPS on IKBα mRNA expression was associated with rapid deacetylation of histone-H3(Lys9) and a dramatic down-regulation of core histone H3 binding. Even though treatment with an HDAC inhibitor produced the same effect as hsp90 inhibition, the effect of 17-AAG was independent of HDAC. We conclude that hsp90 inhibition attenuates NF-κB transcriptional activation by preventing coactivator recruitment and nucleosome eviction from the target promoter in human lung endothelial cells. PMID:24303801

  17. Nitric oxide increases cyclic GMP levels, AMP-activated protein kinase (AMPK)alpha1-specific activity and glucose transport in human skeletal muscle

    DEFF Research Database (Denmark)

    Deshmukh, A S; Long, Y C; de Castro Barbosa, T

    2010-01-01

    -nitrosohydrazino)-1,2-ethylenediamine (spermine NONOate) would increase intracellular cyclic GMP (cGMP) levels and promote glucose transport. METHODS: Skeletal muscle strips were prepared from vastus lateralis muscle biopsies obtained from seven healthy men. Muscle strips were incubated in the absence or presence...... of 5 mmol/l spermine NONOate or 120 nmol/l insulin. The L6 muscle cells were treated with spermine NONOate (20 micromol/l) and incubated in the absence or presence of insulin (120 nmol/l). The direct effect of spermine NONOate and insulin on glucose transport, cGMP levels and signal transduction...... was determined. RESULTS: In human skeletal muscle, spermine NONOate increased glucose transport 2.4-fold (p GMP levels (80-fold, p

  18. Human activity recognition and prediction

    CERN Document Server

    2016-01-01

    This book provides a unique view of human activity recognition, especially fine-grained human activity structure learning, human-interaction recognition, RGB-D data based action recognition, temporal decomposition, and causality learning in unconstrained human activity videos. The techniques discussed give readers tools that provide a significant improvement over existing methodologies of video content understanding by taking advantage of activity recognition. It links multiple popular research fields in computer vision, machine learning, human-centered computing, human-computer interaction, image classification, and pattern recognition. In addition, the book includes several key chapters covering multiple emerging topics in the field. Contributed by top experts and practitioners, the chapters present key topics from different angles and blend both methodology and application, composing a solid overview of the human activity recognition techniques. .

  19. [Cow's milk protein allergy through human milk].

    Science.gov (United States)

    Denis, M; Loras-Duclaux, I; Lachaux, A

    2012-03-01

    Cow's milk protein allergy (CMPA) is the first allergy that affects infants. In this population, the incidence rate reaches 7.5%. The multiplicity and aspecificity of the symptoms makes its diagnosis sometimes complicated, especially in the delayed type (gastrointestinal, dermatological, and cutaneous). CMPA symptoms can develop in exclusively breastfed infants with an incidence rate of 0.5%. It, therefore, raises questions about sensitization to cow's milk proteins through breast milk. Transfer of native bovine proteins such as β-lactoglobulin into the breast milk is controversial: some authors have found bovine proteins in human milk but others point to cross-reactivity between human milk proteins and cow's milk proteins. However, it seems that a small percentage of dietary proteins can resist digestion and become potentially allergenic. Moreover, some authors suspect the transfer of some of these dietary proteins from the maternal bloodstream to breast milk, but the mechanisms governing sensitization are still being studied. Theoretically, CMPA diagnosis is based on clinical observations, prick-test or patch-test results, and cow's milk-specific IgE antibody concentration. A positive food challenge test usually confirms the diagnosis. No laboratory test is available to make a certain diagnosis, but the detection of eosinophil cationic protein (ECP) in the mother's milk, for example, seems to be advantageous since it is linked to CMA. Excluding cow's milk from the mother's diet is the only cure when she still wants to breastfeed. Usually, cow's milk proteins are reintroduced after 6 months of exclusion. Indeed, the prognosis for infants is very good: 80% acquire a tolerance before the age of 3 or 4 years. Mothers should not avoid dairy products during pregnancy and breastfeeding as preventive measures against allergy. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  20. Adiponectin promotes hyaluronan synthesis along with increases in hyaluronan synthase 2 transcripts through an AMP-activated protein kinase/peroxisome proliferator-activated receptor-α-dependent pathway in human dermal fibroblasts

    International Nuclear Information System (INIS)

    Yamane, Takumi; Kobayashi-Hattori, Kazuo; Oishi, Yuichi

    2011-01-01

    Highlights: ► Adiponectin promotes hyaluronan synthesis along with an increase in HAS2 transcripts. ► Adiponectin also increases the phosphorylation of AMPK. ► A pharmacological activator of AMPK increases mRNA levels of PPARα and HAS2. ► Adiponectin-induced HAS2 mRNA expression is blocked by a PPARα antagonist. ► Adiponectin promotes hyaluronan synthesis via an AMPK/PPARα-dependent pathway. -- Abstract: Although adipocytokines affect the functions of skin, little information is available on the effect of adiponectin on the skin. In this study, we investigated the effect of adiponectin on hyaluronan synthesis and its regulatory mechanisms in human dermal fibroblasts. Adiponectin promoted hyaluronan synthesis along with an increase in the mRNA levels of hyaluronan synthase 2 (HAS2), which plays a primary role in hyaluronan synthesis. Adiponectin also increased the phosphorylation of AMP-activated protein kinase (AMPK). A pharmacological activator of AMPK, 5-aminoimidazole-4-carboxamide-1β-ribofuranoside (AICAR), increased mRNA levels of peroxisome proliferator-activated receptor-α (PPARα), which enhances the expression of HAS2 mRNA. In addition, AICAR increased the mRNA levels of HAS2. Adiponectin-induced HAS2 mRNA expression was blocked by GW6471, a PPARα antagonist, in a concentration-dependent manner. These results show that adiponectin promotes hyaluronan synthesis along with increases in HAS2 transcripts through an AMPK/PPARα-dependent pathway in human dermal fibroblasts. Thus, our study suggests that adiponectin may be beneficial for retaining moisture in the skin, anti-inflammatory activity, and the treatment of a variety of cutaneous diseases.

  1. NF-kappa B activity in T cells stably expressing the Tax protein of human T cell lymphotropic virus type I

    International Nuclear Information System (INIS)

    Lacoste, J.; Cohen, L.; Hiscott, J.

    1991-01-01

    The effect of constitutive Tax expression on the interaction of NF-κ B with its recognition sequence and on NF-κ B-dependent gene expression was examined in T lymphoid Jurkat cell lines (19D and 9J) stably transformed with a Tax expression vector. Tax expressing T cell lines contained a constitutive level of NF-κ B binding activity, detectable by mobility shift assay and uv cross-linking using a palindromic NF-κ B probe homologous to the interferon beta PRDII site. In Jurkat and NC2.10 induction with phorbol esters resulted in the appearance of new DNA binding proteins of 85, 75, and 54 kDa, whereas in Tax expressing cells the 85-kDa protein and a 92-kDa DNA binding protein were constitutively induced. Expression of Tax protein in 19D and 9J resulted in transcription of the endogenous NF-kappa B-dependent granulocyte-macrophage colony stimulating factor gene and increased basal level expression of transfected NF-kappa B-regulated promoters. Nonetheless transcription of both the endogenous and the transfected gene was inducible by PMA treatment. Tax expression in Jurkat T cells may alter the stoichiometry of NF-kappa B DNA binding proteins and thus change the expression of NF-kappa B-regulated promoters

  2. Dataset of protein species from human liver

    Directory of Open Access Journals (Sweden)

    Stanislav Naryzhny

    2017-06-01

    Full Text Available This article contains data related to the research article entitled “Zipf׳s law in proteomics” (Naryzhny et al., 2017 [1]. The protein composition in the human liver or hepatocarcinoma (HepG2 cells extracts was estimated using a filter-aided sample preparation (FASP protocol. The protein species/proteoform composition in the human liver was determined by two-dimensional electrophoresis (2-DE followed by Electrospray Ionization Liquid Chromatography-Tandem Mass Spectrometry (ESI LC-MS/MS. In the case of two-dimensional electrophoresis (2-DE, the gel was stained with Coomassie Brilliant Blue R350, and image analysis was performed with ImageMaster 2D Platinum software (GE Healthcare. The 96 sections in the 2D gel were selected and cut for subsequent ESI LC-MS/MS and protein identification. If the same protein was detected in different sections, it was considered to exist as different protein species/proteoforms. A list of human liver proteoforms detected in this way is presented.

  3. Protein Translation and Signaling in Human Eosinophils

    Directory of Open Access Journals (Sweden)

    Stephane Esnault

    2017-09-01

    Full Text Available We have recently reported that, unlike IL-5 and GM-CSF, IL-3 induces increased translation of a subset of mRNAs. In addition, we have demonstrated that Pin1 controls the activity of mRNA binding proteins, leading to enhanced mRNA stability, GM-CSF protein production and prolonged eosinophil (EOS survival. In this review, discussion will include an overview of cap-dependent protein translation and its regulation by intracellular signaling pathways. We will address the more general process of mRNA post-transcriptional regulation, especially regarding mRNA binding proteins, which are critical effectors of protein translation. Furthermore, we will focus on (1 the roles of IL-3-driven sustained signaling on enhanced protein translation in EOS, (2 the mechanisms regulating mRNA binding proteins activity in EOS, and (3 the potential targeting of IL-3 signaling and the signaling leading to mRNA binding activity changes to identify therapeutic targets to treat EOS-associated diseases.

  4. Systematic high-yield production of human secreted proteins in Escherichia coli

    International Nuclear Information System (INIS)

    Dai Xueyu; Chen Qiang; Lian Min; Zhou Yanfeng; Zhou Mo; Lu Shanyun; Chen Yunjia; Luo Jingchu; Gu Xiaocheng; Jiang Ying; Luo Ming; Zheng Xiaofeng

    2005-01-01

    Human secreted proteins play a very important role in signal transduction. In order to study all potential secreted proteins identified from the human genome sequence, systematic production of large amounts of biologically active secreted proteins is a prerequisite. We selected 25 novel genes as a trial case for establishing a reliable expression system to produce active human secreted proteins in Escherichia coli. Expression of proteins with or without signal peptides was examined and compared in E. coli strains. The results indicated that deletion of signal peptides, to a certain extent, can improve the expression of these proteins and their solubilities. More importantly, under expression conditions such as induction temperature, N-terminus fusion peptides need to be optimized in order to express adequate amounts of soluble proteins. These recombinant proteins were characterized as well-folded proteins. This system enables us to rapidly obtain soluble and highly purified human secreted proteins for further functional studies

  5. Standardization for cortisol determination in human blood by competitive protein-binding

    International Nuclear Information System (INIS)

    Okada, H.

    1978-01-01

    Standardization for determination of cortisol from human plasma (17-hydroxycorticosteroids) using competitive protein-binding method is presented. Activated carbon coated with dextrans is used for separation of the hormone-protein complexe and hormone labelled free [pt

  6. Lentin, a novel and potent antifungal protein from shitake mushroom with inhibitory effects on activity of human immunodeficiency virus-1 reverse transcriptase and proliferation of leukemia cells.

    Science.gov (United States)

    Ngai, Patrick H K; Ng, T B

    2003-11-14

    From the fruiting bodies of the edible mushroom Lentinus edodes, a novel protein designated lentin with potent antifungal activity was isolated. Lentin was unadsorbed on DEAE-cellulose, and adsorbed on Affi-gel blue gel and Mono S. The N-terminal sequence of lentin manifested similarity to endoglucanase. Lentin, which had a molecular mass of 27.5 kDa, inhibited mycelial growth in a variety of fungal species including Physalospora piricola, Botrytis cinerea and Mycosphaerella arachidicola. Lentin also exerted an inhibitory activity on HIV-1 reverse transcriptase and proliferation of leukemia cells.

  7. Purification of human alpha uterine protein.

    Science.gov (United States)

    Sutcliffe, R G; Bolton, A E; Sharp, F; Nicholson, L V; MacKinnon, R

    1980-03-01

    Human alpha uterine protein (AUP) has been prepared from extracts of decudua by antibody affinity chromatography, DEAE Sepharose chromatography and by filtration through Sephadex G-150. This procedure yielded a protein fraction containing AUP, which was labelled with 125I by chloramine T. When analysed by SDS gel electrophoresis this radioiodinated protein fraction was found to contain predominantly a single species of protein which was precipitated by antibodies against AUP in antibody-antigen crossed electrophoresis. Rabbit anti-AUP precipitated 55-65% of the tracer in a double-antibody system. Sephadex G150 gel filtration of AUP obtained before and after affinity chromatography provided a molecular weight estimate of 50000. Since SDS gel electrophoresis revealed a polypeptide molecular weight of 23000-25000, it is suggested that AUP is a dimer.

  8. The human CFTR protein expressed in CHO cells activates aquaporin-3 in a cAMP-dependent pathway: study by digital holographic microscopy

    KAUST Repository

    Jourdain, P.

    2013-12-11

    The transmembrane water movements during cellular processes and their relationship to ionic channel activity remain largely unknown. As an example, in epithelial cells it was proposed that the movement of water could be directly linked to cystic fibrosis transmembrane conductance regulator (CFTR) protein activity through a cAMP-stimulated aqueous pore, or be dependent on aquaporin. Here, we used digital holographic microscopy (DHM) an interferometric technique to quantify in situ the transmembrane water fluxes during the activity of the epithelial chloride channel, CFTR, measured by patch-clamp and iodide efflux techniques. We showed that the water transport measured by DHM is fully inhibited by the selective CFTR blocker CFTRinh172 and is absent in cells lacking CFTR. Of note, in cells expressing the mutated version of CFTR (F508del-CFTR), which mimics the most common genetic alteration encountered in cystic fibrosis, we also show that the water movement is profoundly altered but restored by pharmacological manipulation of F508del-CFTR-defective trafficking. Importantly, whereas activation of this endogenous water channel required a cAMP-dependent stimulation of CFTR, activation of CFTR or F508del-CFTR by two cAMP-independent CFTR activators, genistein and MPB91, failed to trigger water movements. Finally, using a specific small-interfering RNA against the endogenous aquaporin AQP3, the water transport accompanying CFTR activity decreased. We conclude that water fluxes accompanying CFTR activity are linked to AQP3 but not to a cAMP-stimulated aqueous pore in the CFTR protein.

  9. Activation of the polyomavirus enhancer by a murine activator protein 1 (AP1) homolog and two contiguous proteins.

    OpenAIRE

    Martin, M E; Piette, J; Yaniv, M; Tang, W J; Folk, W R

    1988-01-01

    The polyomavirus enhancer is composed of multiple DNA sequence elements serving as binding sites for proteins present in mouse nuclear extracts that activate transcription and DNA replication. We have identified three such proteins and their binding sites and correlate them with enhancer function. Mutation of nucleotide (nt) 5140 in the enhancer alters the binding site (TGACTAA, nt 5139-5145) for polyomavirus enhancer A binding protein 1 (PEA1), a murine homolog of the human transcription fac...

  10. Mitogen-activated protein kinases mediate Mycobacterium ...

    Indian Academy of Sciences (India)

    2012-01-19

    Jan 19, 2012 ... CD44, an adhesion molecule, has been reported to be a binding site for ... receptors in mediating mitogen-activated protein kinase activation. ... surface expression and tumour necrosis factor-alpha levels, ... Abbreviations used: Abs, antibodies; ANOVA, analysis of variance; AP-1, activator protein -1; BCG, ...

  11. Human Activity in the Web

    OpenAIRE

    Radicchi, Filippo

    2009-01-01

    The recent information technology revolution has enabled the analysis and processing of large-scale datasets describing human activities. The main source of data is represented by the Web, where humans generally use to spend a relevant part of their day. Here we study three large datasets containing the information about Web human activities in different contexts. We study in details inter-event and waiting time statistics. In both cases, the number of subsequent operations which differ by ta...

  12. UV-induced DNA-binding proteins in human cells

    International Nuclear Information System (INIS)

    Glazer, P.M.; Greggio, N.A.; Metherall, J.E.; Summers, W.C.

    1989-01-01

    To investigate the response of human cells to DNA-damaging agents such as UV irradiation, the authors examined nuclear protein extracts of UV-irradiated HeLa cells for the presence of DNA-binding proteins. Electrophoretically separated proteins were transferred to a nitrocellulose filter that was subsequently immersed in a binding solution containing radioactively labeled DNA probes. Several DNA-binding proteins were induced in HeLa cells after UV irradiation. These included proteins that bind predominantly double-stranded DNA and proteins that bind both double-stranded and single-stranded DNA. The binding proteins were induced in a dose-dependent manner by UV light. Following a dose of 12 J/m 2 , the binding proteins in the nuclear extracts increased over time to a peak in the range of 18 hr after irradiation. Experiments with metabolic inhibitors (cycloheximide and actinomycin D) revealed that de novo synthesis of these proteins is not required for induction of the binding activities, suggesting that the induction is mediated by protein modification

  13. Modeling and protein engineering studies of active and inactive states of human dopamine D2 receptor (D2R) and investigation of drug/receptor interactions.

    Science.gov (United States)

    Salmas, Ramin Ekhteiari; Yurtsever, Mine; Stein, Matthias; Durdagi, Serdar

    2015-05-01

    Homology model structures of the dopamine D2 receptor (D2R) were generated starting from the active and inactive states of β2-adrenergic crystal structure templates. To the best of our knowledge, the active conformation of D2R was modeled for the first time in this study. The homology models are built and refined using MODELLER and ROSETTA programs. Top-ranked models have been validated with ligand docking simulations and in silico Alanine-scanning mutagenesis studies. The derived extra-cellular loop region of the protein models is directed toward the binding site cavity which is often involved in ligand binding. The binding sites of protein models were refined using induced fit docking to enable the side-chain refinement during ligand docking simulations. The derived models were then tested using molecular modeling techniques on several marketed drugs for schizophrenia. Alanine-scanning mutagenesis and molecular docking studies gave similar results for marketed drugs tested. We believe that these new D2 receptor models will be very useful for a better understanding of the mechanisms of action of drugs to be targeted to the binding sites of D2Rs and they will contribute significantly to drug design studies involving G-protein-coupled receptors in the future.

  14. Redox activity distinguishes solid-state electron transport from solution-based electron transfer in a natural and artificial protein: cytochrome C and hemin-doped human serum albumin.

    Science.gov (United States)

    Amdursky, Nadav; Ferber, Doron; Pecht, Israel; Sheves, Mordechai; Cahen, David

    2013-10-28

    Integrating proteins in molecular electronic devices requires control over their solid-state electronic transport behavior. Unlike "traditional" electron transfer (ET) measurements of proteins that involve liquid environments and a redox cycle, no redox cofactor is needed for solid-state electron transport (ETp) across the protein. Here we show the fundamental difference between these two approaches by macroscopic area measurements, which allow measuring ETp temperature dependence down to cryogenic temperatures, via cytochrome C (Cyt C), an ET protein with a heme (Fe-porphyrin) prosthetic group as a redox centre. We compare the ETp to electrochemical ET measurements, and do so also for the protein without the Fe (with metal-free porphyrin) and without porphyrin. As removing the porphyrin irreversibly alters the protein's conformation, we repeat these measurements with human serum albumin (HSA), 'doped' (by non-covalent binding) with a single hemin equivalent, i.e., these natural and artificial proteins share a common prosthetic group. ETp via Cyt C and HSA-hemin are very similar in terms of current magnitude and temperature dependence, which suggests similar ETp mechanisms via these two systems, thermally activated hopping (with ~0.1 eV activation energy) >190 K and tunneling by superexchange Fe(3+) + e(-)), measured by electrochemistry of HSA-hemin are only 4 times lower than those for Cyt C. However, while removing the Fe redox centre from the porphyrin ring markedly affects the ET rate, it hardly changes the ETp currents through these proteins, while removing the macrocycle (from HSA, which retains its conformation) significantly reduces ETp efficiency. These results show that solid-state ETp across proteins does not require the presence of a redox cofactor, and that while for ET the Fe ion is the main electron mediator, for ETp the porphyrin ring has this function.

  15. Recombinant human bone morphogenetic protein induces bone formation

    International Nuclear Information System (INIS)

    Wang, E.A.; Rosen, V.; D'Alessandro, J.S.; Bauduy, M.; Cordes, P.; Harada, T.; Israel, D.I.; Hewick, R.M.; Kerns, K.M.; LaPan, P.; Luxenberg, D.P.; McQuaid, D.; Moutsatsos, I.K.; Nove, J.; Wozney, J.M.

    1990-01-01

    The authors have purified and characterized active recombinant human bone morphogenetic protein (BMP) 2A. Implantation of the recombinant protein in rats showed that a single BMP can induce bone formation in vivo. A dose-response and time-course study using the rat ectopic bone formation assay revealed that implantation of 0.5-115 μg of partially purified recombinant human BMP-2A resulted in cartilage by day 7 and bone formation by day 14. The time at which bone formation occurred was dependent on the amount of BMP-2A implanted; at high doses bone formation could be observed at 5 days. The cartilage- and bone-inductive activity of the recombinant BMP-2A is histologically indistinguishable from that of bone extracts. Thus, recombinant BMP-2A has therapeutic potential to promote de novo bone formation in humans

  16. Curcumin decreases the expression of Pokemon by suppressing the binding activity of the Sp1 protein in human lung cancer cells.

    Science.gov (United States)

    Cui, Jiajun; Meng, Xianfeng; Gao, Xudong; Tan, Guangxuan

    2010-03-01

    Pokemon, which stands for POK erythroid myeloid ontogenic factor, can regulate expression of many genes and plays an important role in tumorigenesis. Curcumin, a natural and non-toxic yellow compound, has capacity for antioxidant, free radical scavenger, anti-inflammatory properties. Recent studies shows it is a potential inhibitor of cell proliferation in a variety of tumour cells. To investigate whether curcumin can regulate the expression of Pokemon, a series of experiments were carried out. Transient transfection experiments demonstrated that curcumin could decrease the activity of the Pokemon promoter. Western blot analysis suggested that curcumin could significantly decrease the expression of the Pokemon. Overexpression of Sp1 could enhance the activity of the Pokemon promoter, whereas knockdown of Sp1 could decrease its activity. More important, we also found that curcumin could decrease the expression of the Pokemon by suppressing the stimulation of the Sp1 protein. Therefore, curcumin is a potential reagent for tumour therapy which may target Pokemon.

  17. Biological role of copper and copper-containing proteins in human and animal organism

    OpenAIRE

    ANTONYAK H.L.; VAZHNENKO A.V.; PANAS N.E.

    2011-01-01

    Current scientific data related to copper metabolism and functional activity of Cu-containing proteins in human and animal cells are reviewed in the article. Important functional role of this essential element in human and animal organism is analyzed.

  18. Essential Roles of Raf/Extracellular Signal-regulated Kinase/Mitogen-activated Protein Kinase Pathway, YY1, and Ca2+ Influx in Growth Arrest of Human Vascular Smooth Muscle Cells by Bilirubin*

    Science.gov (United States)

    Stoeckius, Marlon; Erat, Anna; Fujikawa, Tatsuya; Hiromura, Makoto; Koulova, Anna; Otterbein, Leo; Bianchi, Cesario; Tobiasch, Edda; Dagon, Yossi; Sellke, Frank W.; Usheva, Anny

    2012-01-01

    The biological effects of bilirubin, still poorly understood, are concentration-dependent ranging from cell protection to toxicity. Here we present data that at high nontoxic physiological concentrations, bilirubin inhibits growth of proliferating human coronary artery smooth muscle cells by three events. It impairs the activation of Raf/ERK/MAPK pathway and the cellular Raf and cyclin D1 content that results in retinoblastoma protein hypophosphorylation on amino acids S608 and S780. These events impede the release of YY1 to the nuclei and its availability to regulate the expression of genes and to support cellular proliferation. Moreover, altered calcium influx and calpain II protease activation leads to proteolytical degradation of transcription factor YY1. We conclude that in the serum-stimulated human vascular smooth muscle primary cell cultures, bilirubin favors growth arrest, and we propose that this activity is regulated by its interaction with the Raf/ERK/MAPK pathway, effect on cyclin D1 and Raf content, altered retinoblastoma protein profile of hypophosphorylation, calcium influx, and YY1 proteolysis. We propose that these activities together culminate in diminished 5 S and 45 S ribosomal RNA synthesis and cell growth arrest. The observations provide important mechanistic insight into the molecular mechanisms underlying the transition of human vascular smooth muscle cells from proliferative to contractile phenotype and the role of bilirubin in this transition. PMID:22262839

  19. Cow's milk proteins in human milk.

    Science.gov (United States)

    Coscia, A; Orrù, S; Di Nicola, P; Giuliani, F; Rovelli, I; Peila, C; Martano, C; Chiale, F; Bertino, E

    2012-01-01

    Cow's milk proteins (CMPs) are among the best characterized food allergens. Cow's milk contains more than twenty five different proteins, but only whey proteins alpha-lactalbumin, beta-lactoglobulin, bovine serum albumin (BSA), and lactoferrin, as well as the four caseins, have been identified as allergens. Aim of this study was to investigate by proteomics techniques cow's milk allergens in human colostrum of term and preterm newborns' mothers, not previously detected, in order to understand if such allergens could be cause of sensitization during lactation. Term colostrum samples from 62 healthy mothers and preterm colostrum samples from 11 healthy mothers were collected for this purpose. The most relevant finding was the detection of the intact bovine alpha-S1-casein in both term and preterm colostrum. Using this method, which allows direct proteins identification, beta-lactoglobulin was not detected in any of colostrum samples. According to our results bovine alpha 1 casein that is considered a major cow's milk allergen is readily secreted in human milk: further investigations are needed in order to clarify if alpha-1-casein has a major role in sensitization or tolerance to cow's milk of exclusively breastfed predisposed infants.

  20. Chitin and stress induced protein kinase activation

    DEFF Research Database (Denmark)

    Kenchappa, Chandra Shekar; Azevedo da Silva, Raquel; Bressendorff, Simon

    2017-01-01

    The assays described here are pertinent to protein kinase studies in any plant. They include an immunoblot phosphorylation/activation assay and an in-gel activity assay for MAP kinases (MPKs) using the general protein kinase substrate myelin basic protein. They also include a novel in-gel peptide...... substrate assay for Snf1-related kinase family 2 members (SnRK2s). This kinase family-specific assay overcomes some limitations of in-gel assays and permits the identification of different types of kinase activities in total protein extracts....

  1. Protein kinase C promotes restoration of calcium homeostasis to platelet activating factor-stimulated human neutrophils by inhibition of phospholipase C

    Directory of Open Access Journals (Sweden)

    Anderson Ronald

    2009-10-01

    Full Text Available Abstract Background The role of protein kinase C (PKC in regulating the activity of phospholipase C (PLC in neutrophils activated with the chemoattractant, platelet-activating factor (PAF, 20 and 200 nM, was probed in the current study using the selective PKC inhibitors, GF10903X (0.5 - 1 μM and staurosporine (400 nM. Methods Alterations in cytosolic Ca2+, Ca2+ influx, inositol triphosphate (IP3, and leukotriene B4 production were measured using spectrofluorimetric, radiometric and competitive binding radioreceptor and immunoassay procedures, respectively. Results Activation of the cells with PAF was accompanied by an abrupt increase in cytosolic Ca2+ followed by a gradual decline towards basal levels. Pretreatment of neutrophils with the PKC inhibitors significantly increased IP3 production with associated enhanced Ca2+ release from storage vesicles, prolongation of the peak cytosolic Ca2+ transients, delayed clearance and exaggerated reuptake of the cation, and markedly increased synthesis of LTB4. The alterations in Ca2+ fluxes observed with the PKC inhibitors were significantly attenuated by U73122, a PLC inhibitor, as well as by cyclic AMP-mediated upregulation of the Ca2+-resequestering endomembrane ATPase. Taken together, these observations are compatible with a mechanism whereby PKC negatively modulates the activity of PLC, with consequent suppression of IP3 production and down-regulation of Ca2+ mediated pro-inflammatory responses of PAF-activated neutrophils. Conclusion Although generally considered to initiate and/or amplify intracellular signalling cascades which activate and sustain the pro-inflammatory activities of neutrophils and other cell types, the findings of the current study have identified a potentially important physiological, anti-inflammatory function for PKC, at least in neutrophils.

  2. Prediction of extracellular proteases of the human pathogen Helicobacter pylori reveals proteolytic activity of the Hp1018/19 protein HtrA.

    Directory of Open Access Journals (Sweden)

    Martin Löwer

    Full Text Available Exported proteases of Helicobacter pylori (H. pylori are potentially involved in pathogen-associated disorders leading to gastric inflammation and neoplasia. By comprehensive sequence screening of the H. pylori proteome for predicted secreted proteases, we retrieved several candidate genes. We detected caseinolytic activities of several such proteases, which are released independently from the H. pylori type IV secretion system encoded by the cag pathogenicity island (cagPAI. Among these, we found the predicted serine protease HtrA (Hp1019, which was previously identified in the bacterial secretome of H. pylori. Importantly, we further found that the H. pylori genes hp1018 and hp1019 represent a single gene likely coding for an exported protein. Here, we directly verified proteolytic activity of HtrA in vitro and identified the HtrA protease in zymograms by mass spectrometry. Overexpressed and purified HtrA exhibited pronounced proteolytic activity, which is inactivated after mutation of Ser205 to alanine in the predicted active center of HtrA. These data demonstrate that H. pylori secretes HtrA as an active protease, which might represent a novel candidate target for therapeutic intervention strategies.

  3. A plasma coagulation assay for an activated protein C-independent anticoagulant activity of protein S

    NARCIS (Netherlands)

    van Wijnen, M.; van 't Veer, C.; Meijers, J. C.; Bertina, R. M.; Bouma, B. N.

    1998-01-01

    To study the physiological importance of the activated protein C (APC)-independent anticoagulant activity of protein S, we developed an assay specific for this activity. The ability of protein S to prolong the clotting time in an APC-independent way was expressed as the ratio of the clotting time in

  4. Depletion of WRN protein causes RACK1 to activate several protein kinase C isoforms

    DEFF Research Database (Denmark)

    Massip, L; Garand, C; Labbé, A

    2010-01-01

    show that a knock down of the WRN protein in normal human fibroblasts induces phosphorylation and activation of several protein kinase C (PKC) enzymes. Using a tandem affinity purification strategy, we found that WRN physically and functionally interacts with receptor for activated C-kinase 1 (RACK1......), a highly conserved anchoring protein involved in various biological processes, such as cell growth and proliferation. RACK1 binds strongly to the RQC domain of WRN and weakly to its acidic repeat region. Purified RACK1 has no impact on the helicase activity of WRN, but selectively inhibits WRN exonuclease...... activity in vitro. Interestingly, knocking down RACK1 increased the cellular frequency of DNA breaks. Depletion of the WRN protein in return caused a fraction of nuclear RACK1 to translocate out of the nucleus to bind and activate PKCdelta and PKCbetaII in the membrane fraction of cells. In contrast...

  5. Human telomerase activity regulation

    OpenAIRE

    Wojtyla, Aneta; Gladych, Marta; Rubis, Blazej

    2010-01-01

    Telomerase has been recognized as a relevant factor distinguishing cancer cells from normal cells. Thus, it has become a very promising target for anticancer therapy. The cell proliferative potential can be limited by replication end problem, due to telomeres shortening, which is overcome in cancer cells by telomerase activity or by alternative telomeres lengthening (ALT) mechanism. However, this multisubunit enzymatic complex can be regulated at various levels, including expression control b...

  6. A scored human protein-protein interaction network to catalyze genomic interpretation

    DEFF Research Database (Denmark)

    Li, Taibo; Wernersson, Rasmus; Hansen, Rasmus B

    2017-01-01

    Genome-scale human protein-protein interaction networks are critical to understanding cell biology and interpreting genomic data, but challenging to produce experimentally. Through data integration and quality control, we provide a scored human protein-protein interaction network (InWeb_InBioMap,......Genome-scale human protein-protein interaction networks are critical to understanding cell biology and interpreting genomic data, but challenging to produce experimentally. Through data integration and quality control, we provide a scored human protein-protein interaction network (In...

  7. Robust, synergistic regulation of human gene expression using TALE activators.

    Science.gov (United States)

    Maeder, Morgan L; Linder, Samantha J; Reyon, Deepak; Angstman, James F; Fu, Yanfang; Sander, Jeffry D; Joung, J Keith

    2013-03-01

    Artificial activators designed using transcription activator-like effector (TALE) technology have broad utility, but previous studies suggest that these monomeric proteins often exhibit low activities. Here we demonstrate that TALE activators can robustly function individually or in synergistic combinations to increase expression of endogenous human genes over wide dynamic ranges. These findings will encourage applications of TALE activators for research and therapy, and guide design of monomeric TALE-based fusion proteins.

  8. Diffusion of protein through the human cornea.

    Science.gov (United States)

    Charalel, Resmi A; Engberg, Kristin; Noolandi, Jaan; Cochran, Jennifer R; Frank, Curtis; Ta, Christopher N

    2012-01-01

    To determine the rate of diffusion of myoglobin and bovine serum albumin (BSA) through the human cornea. These small proteins have hydrodynamic diameters of approximately 4.4 and 7.2 nm, and molecular weights of 16.7 and 66 kDa, for myoglobin and BSA, respectively. Diffusion coefficients were measured using a diffusion chamber where the protein of interest and balanced salt solution were in different chambers separated by an ex vivo human cornea. Protein concentrations in the balanced salt solution chamber were measured over time. Diffusion coefficients were calculated using equations derived from Fick's law and conservation of mass in a closed system. Our experiments demonstrate that the diffusion coefficient of myoglobin is 5.5 ± 0.9 × 10(-8) cm(2)/s (n = 8; SD = 1.3 × 10(-8) cm(2)/s; 95% CI: 4.6 × 10(-8) to 6.4 × 10(-8) cm(2)/s) and the diffusion coefficient of BSA is 3.1 ± 1.0 × 10(-8) cm(2)/s (n = 8; SD = 1.4 × 10(-8) cm(2)/s; 95% CI: 2.1 × 10(-8) to 4.1 × 10(-8) cm(2)/s). Our study suggests that molecules as large as 7.2 nm may be able to passively diffuse through the human cornea. With applications in pharmacotherapy and the development of an artificial cornea, further experiments are warranted to fully understand the limits of human corneal diffusion and its clinical relevance. Copyright © 2012 S. Karger AG, Basel.

  9. Vitamin K3-2,3-epoxide induction of apoptosis with activation of ROS-dependent ERK and JNK protein phosphorylation in human glioma cells.

    Science.gov (United States)

    Wu, Jender; Chien, Chih-Chiang; Yang, Liang-Yo; Huang, Guan-Cheng; Cheng, Min-Chi; Lin, Che-Tong; Shen, Shing-Chuan; Chen, Yen-Chou

    2011-08-15

    2-Methyl-1,4-naphthoquinone (menadione or vitamin K3; EPO) and K3-2,3-epoxide (EPO1), but not vitamin K3-3-OH (EPO2), exhibited cytotoxicity that caused DNA fragmentation and chromatin condensation in U87 and C6 cells. EPO1 showed more-potent cytotoxicity than EPO, and the IC(50) values of EPO and EPO1 in U87 cells were 37.5 and 15.7μM, respectively. Activation of caspase 3 enzyme activity with cleavage of caspase 3 protein was detected in EPO1-treated U87 and C6 cells, and the addition of the caspase 3 peptidyl inhibitor, DEVD-FMK, reduced the cytotoxic effect of EPO1. An increase in the intracellular ROS level by EPO1 was observed in the DCHF-DA analysis, and EPO1-induced apoptosis and caspase 3 protein cleavage were prevented by adding the antioxidant, N-acetyl-cysteine (NAC), with decreased ROS production elicited by EPO1. Activation of ERK and JNK, but not p38, via phosphorylation induction was identified in EPO1- but not EPO- or EPO2-treated U87 and C6 cells, and this was blocked by adding NAC. However, the ERK inhibitor, PD98059, and the JNK inhibitor, SP600125, showed no effect on EPO1-induced cytotoxicity in either cell type. Our findings demonstrate that 2,3-epoxide substitution significantly potentiates the apoptotic effect of vitamin K3 via stimulating ROS production, which may be useful in the chemotherapy of glioblastoma cells. Copyright © 2011. Published by Elsevier Ireland Ltd.

  10. Human sperm degradation of zona pellucida proteins contributes to fertilization.

    Science.gov (United States)

    Saldívar-Hernández, Analilia; González-González, María E; Sánchez-Tusié, Ana; Maldonado-Rosas, Israel; López, Pablo; Treviño, Claudia L; Larrea, Fernando; Chirinos, Mayel

    2015-09-02

    The mammalian oocyte extracellular matrix known as the zona pellucida (ZP) acts as a barrier to accomplish sperm fusion with the female gamete. Although penetration of the ZP is a limiting event to achieve fertilization, this is one of the least comprehended stages of gamete interaction. Even though previous studies suggest that proteases of sperm origin contribute to facilitate the passage of sperm through the ZP, in human this process is not yet fully understood. The aim of this study was to determine the ability of human sperm to degrade recombinant human ZP (rhZPs) proteins and to characterize the proteases involved in this process. Purified rhZP2, rhZP3 and rhZP4 proteins were incubated with capacitated sperm and the proteolytic activity was determined by Western blot analysis. To further characterize the proteases involved, parallel incubations were performed in the presence of the protease inhibitors o-phenanthroline, benzamidine and MG-132 meant to block the activity of metalloproteases, serine proteases and the proteasome, respectively. Additionally, protease inhibitors effect on sperm-ZP binding was evaluated by hemizona assay. The results showed that rhZPs were hydrolyzed in the presence of capacitated sperm. O-phenanthroline inhibited the degradation of rhZP3, MG-132 inhibited the degradation of rhZP4 and benzamidine inhibited the degradation of the three proteins under investigation. Moreover, hemizona assays demonstrated that sperm proteasome inhibition impairs sperm interaction with human native ZP. This study suggests that sperm proteasomes could participate in the degradation of ZP, particularly of the ZP4 protein. Besides, metalloproteases may be involved in specific degradation of ZP3 while serine proteases may contribute to unspecific degradation of the ZP. These findings suggest that localized degradation of ZP proteins by sperm is probably involved in ZP penetration and may be of help in understanding the mechanisms of fertilization in humans.

  11. Inferring modules from human protein interactome classes

    Directory of Open Access Journals (Sweden)

    Chaurasia Gautam

    2010-07-01

    Full Text Available Abstract Background The integration of protein-protein interaction networks derived from high-throughput screening approaches and complementary sources is a key topic in systems biology. Although integration of protein interaction data is conventionally performed, the effects of this procedure on the result of network analyses has not been examined yet. In particular, in order to optimize the fusion of heterogeneous interaction datasets, it is crucial to consider not only their degree of coverage and accuracy, but also their mutual dependencies and additional salient features. Results We examined this issue based on the analysis of modules detected by network clustering methods applied to both integrated and individual (disaggregated data sources, which we call interactome classes. Due to class diversity, we deal with variable dependencies of data features arising from structural specificities and biases, but also from possible overlaps. Since highly connected regions of the human interactome may point to potential protein complexes, we have focused on the concept of modularity, and elucidated the detection power of module extraction algorithms by independent validations based on GO, MIPS and KEGG. From the combination of protein interactions with gene expressions, a confidence scoring scheme has been proposed before proceeding via GO with further classification in permanent and transient modules. Conclusions Disaggregated interactomes are shown to be informative for inferring modularity, thus contributing to perform an effective integrative analysis. Validation of the extracted modules by multiple annotation allows for the assessment of confidence measures assigned to the modules in a protein pathway context. Notably, the proposed multilayer confidence scheme can be used for network calibration by enabling a transition from unweighted to weighted interactomes based on biological evidence.

  12. Control of NF-kB activity in human melanoma by bromodomain and extra-terminal protein inhibitor I-BET151.

    Science.gov (United States)

    Gallagher, Stuart J; Mijatov, Branka; Gunatilake, Dilini; Gowrishankar, Kavitha; Tiffen, Jessamy; James, Wilmott; Jin, Lei; Pupo, Gulietta; Cullinane, Carleen; McArthur, Grant A; Tummino, Peter J; Rizos, Helen; Hersey, Peter

    2014-11-01

    The transcription factor NF-kappaB (NF-kB) is a key regulator of cytokine and chemokine production in melanoma and is responsible for symptoms such as anorexia, fatigue, and weight loss. In addition, NF-kB is believed to contribute to progression of the disease by upregulation of cell cycle and anti-apoptotic genes and to contribute to resistance against targeted therapies and immunotherapy. In this study, we have examined the ability of the bromodomain and extra-terminal (BET) protein inhibitor I-BET151 to inhibit NF-kB in melanoma cells. We show that I-BET151 is a potent, selective inhibitor of a number of NF-kB target genes involved in induction of inflammation and cell cycle regulation and downregulates production of cytokines such as IL-6 and IL-8. SiRNA studies indicate that BRD2 is the main BET protein involved in regulation of NF-kB and that I-BET151 caused transcriptional downregulation of the NF-kB subunit p105/p50. These results suggest that BET inhibitors may have an important role in treatment of melanoma where activation of NF-kB may have a key pathogenic role. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Mitochondrial Fusion Proteins and Human Diseases

    Directory of Open Access Journals (Sweden)

    Michela Ranieri

    2013-01-01

    Full Text Available Mitochondria are highly dynamic, complex organelles that continuously alter their shape, ranging between two opposite processes, fission and fusion, in response to several stimuli and the metabolic demands of the cell. Alterations in mitochondrial dynamics due to mutations in proteins involved in the fusion-fission machinery represent an important pathogenic mechanism of human diseases. The most relevant proteins involved in the mitochondrial fusion process are three GTPase dynamin-like proteins: mitofusin 1 (MFN1 and 2 (MFN2, located in the outer mitochondrial membrane, and optic atrophy protein 1 (OPA1, in the inner membrane. An expanding number of degenerative disorders are associated with mutations in the genes encoding MFN2 and OPA1, including Charcot-Marie-Tooth disease type 2A and autosomal dominant optic atrophy. While these disorders can still be considered rare, defective mitochondrial dynamics seem to play a significant role in the molecular and cellular pathogenesis of more common neurodegenerative diseases, for example, Alzheimer’s and Parkinson’s diseases. This review provides an overview of the basic molecular mechanisms involved in mitochondrial fusion and focuses on the alteration in mitochondrial DNA amount resulting from impairment of mitochondrial dynamics. We also review the literature describing the main disorders associated with the disruption of mitochondrial fusion.

  14. Radioimmunoassay of inactive creatine kinase B protein in human plasma

    Energy Technology Data Exchange (ETDEWEB)

    Burnam, M H; Shell, W E [California Univ., Los Angeles (USA). School of Medicine

    1981-08-27

    The authors describe a rapid, sensitive radioimmunoassay for enzymatically inactive creatine kinase B protein (CK-Bi) in plasma. /sup 125/I-CK-Bi of high specific activity and good stability was prepared by oxidant-based iodination. A 12-minute first antibody incubation was used. Bound and free antigen were separated by a second antibody system. Large excesses of purified CK-MM from human skeletal muscle did not react in the assay. Cross reactivity to CK-MB purified from the plasma of patients with acute myocardial infarction was negligible. The 95th percentile of plasma CK-Bi in 150 adults was 145 ..mu..g equivalents/ml. Within-assay and between-assay precision ranged from 5% to 9% and 6% to 10%, respectively. Evidence is presented indicating that the assay measures inactive creatine kinase B protein, a protein not measured by current assay systems dependent on biological activity.

  15. Radioimmunoassay of inactive creatine kinase B protein in human plasma

    International Nuclear Information System (INIS)

    Burnam, M.H.; Shell, W.E.

    1981-01-01

    The authors describe a rapid, sensitive radioimmunoassay for enzymatically inactive creatine kinase B protein (CK-Bi) in plasma. 125 I-CK-Bi of high specific activity and good stability was prepared by oxidant-based iodination. A 12-minute first antibody incubation was used. Bound and free antigen were separated by a second antibody system. Large excesses of purified CK-MM from human skeletal muscle did not react in the assay. Cross reactivity to CK-MB purified from the plasma of patients with acute myocardial infarction was negligible. The 95th percentile of plasma CK-Bi in 150 adults was 145 μg equivalents/ml. Within-assay and between-assay precision ranged from 5% to 9% and 6% to 10%, respectively. Evidence is presented indicating that the assay measures inactive creatine kinase B protein, a protein not measured by current assay systems dependent on biological activity. (Auth.)

  16. Dietary protein considerations to support active aging.

    Science.gov (United States)

    Wall, Benjamin T; Cermak, Naomi M; van Loon, Luc J C

    2014-11-01

    Given our rapidly aging world-wide population, the loss of skeletal muscle mass with healthy aging (sarcopenia) represents an important societal and public health concern. Maintaining or adopting an active lifestyle alleviates age-related muscle loss to a certain extent. Over time, even small losses of muscle tissue can hinder the ability to maintain an active lifestyle and, as such, contribute to the development of frailty and metabolic disease. Considerable research focus has addressed the application of dietary protein supplementation to support exercise-induced gains in muscle mass in younger individuals. In contrast, the role of dietary protein in supporting the maintenance (or gain) of skeletal muscle mass in active older persons has received less attention. Older individuals display a blunted muscle protein synthetic response to dietary protein ingestion. However, this reduced anabolic response can largely be overcome when physical activity is performed in close temporal proximity to protein consumption. Moreover, recent evidence has helped elucidate the optimal type and amount of dietary protein that should be ingested by the older adult throughout the day in order to maximize the skeletal muscle adaptive response to physical activity. Evidence demonstrates that when these principles are adhered to, muscle maintenance or hypertrophy over prolonged periods can be further augmented in active older persons. The present review outlines the current understanding of the role that dietary protein occupies in the lifestyle of active older adults as a means to increase skeletal muscle mass, strength and function, and thus support healthier aging.

  17. Rescue of Learning and Memory Deficits in the Human Nonsyndromic Intellectual Disability Cereblon Knock-Out Mouse Model by Targeting the AMP-Activated Protein Kinase-mTORC1 Translational Pathway.

    Science.gov (United States)

    Bavley, Charlotte C; Rice, Richard C; Fischer, Delaney K; Fakira, Amanda K; Byrne, Maureen; Kosovsky, Maria; Rizzo, Bryant K; Del Prete, Dolores; Alaedini, Armin; Morón, Jose A; Higgins, Joseph J; D'Adamio, Luciano; Rajadhyaksha, Anjali M

    2018-03-14

    intelligence quotient between 50 and 70 but devoid of other phenotypic features, making cereblon an ideal protein for the study of the fundamental aspects of learning and memory. Here, using the cereblon knock-out mouse model, we show that cereblon deficiency disrupts learning, memory, and synaptic function via AMP-activated protein kinase hyperactivity, downregulation of mTORC1, and dysregulation of excitatory synapses, with no changes in social or repetitive behaviors, consistent with findings in the human population. This establishes the cereblon knock-out mouse as a model of pure ID without the confounding behavioral phenotypes associated with other current models of ID. Copyright © 2018 the authors 0270-6474/18/382781-16$15.00/0.

  18. Transfer of C-terminal residues of human apolipoprotein A-I to insect apolipophorin III creates a two-domain chimeric protein with enhanced lipid binding activity.

    Science.gov (United States)

    Horn, James V C; Ellena, Rachel A; Tran, Jesse J; Beck, Wendy H J; Narayanaswami, Vasanthy; Weers, Paul M M

    2017-08-01

    Apolipophorin III (apoLp-III) is an insect apolipoprotein (18kDa) that comprises a single five-helix bundle domain. In contrast, human apolipoprotein A-I (apoA-I) is a 28kDa two-domain protein: an α-helical N-terminal domain (residues 1-189) and a less structured C-terminal domain (residues 190-243). To better understand the apolipoprotein domain organization, a novel chimeric protein was engineered by attaching residues 179 to 243 of apoA-I to the C-terminal end of apoLp-III. The apoLp-III/apoA-I chimera was successfully expressed and purified in E. coli. Western blot analysis and mass spectrometry confirmed the presence of the C-terminal domain of apoA-I within the chimera. While parent apoLp-III did not self-associate, the chimera formed oligomers similar to apoA-I. The chimera displayed a lower α-helical content, but the stability remained similar compared to apoLp-III, consistent with the addition of a less structured domain. The chimera was able to solubilize phospholipid vesicles at a significantly higher rate compared to apoLp-III, approaching that of apoA-I. The chimera was more effective in protecting phospholipase C-treated low density lipoprotein from aggregation compared to apoLp-III. In addition, binding interaction of the chimera with phosphatidylglycerol vesicles and lipopolysaccharides was considerably improved compared to apoLp-III. Thus, addition of the C-terminal domain of apoA-I to apoLp-III created a two-domain protein, with self-association, lipid and lipopolysaccharide binding properties similar to apoA-I. The apoA-I like behavior of the chimera indicate that these properties are independent from residues residing in the N-terminal domain of apoA-I, and that they can be transferred from apoA-I to apoLp-III. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Crystal structure of human protein kinase CK2

    DEFF Research Database (Denmark)

    Niefind, K; Guerra, B; Ermakowa, I

    2001-01-01

    The crystal structure of a fully active form of human protein kinase CK2 (casein kinase 2) consisting of two C-terminally truncated catalytic and two regulatory subunits has been determined at 3.1 A resolution. In the CK2 complex the regulatory subunits form a stable dimer linking the two catalyt...... as a docking partner for various protein kinases. Furthermore it shows an inter-domain mobility in the catalytic subunit known to be functionally important in protein kinases and detected here for the first time directly within one crystal structure.......The crystal structure of a fully active form of human protein kinase CK2 (casein kinase 2) consisting of two C-terminally truncated catalytic and two regulatory subunits has been determined at 3.1 A resolution. In the CK2 complex the regulatory subunits form a stable dimer linking the two catalytic...... subunits, which make no direct contact with one another. Each catalytic subunit interacts with both regulatory chains, predominantly via an extended C-terminal tail of the regulatory subunit. The CK2 structure is consistent with its constitutive activity and with a flexible role of the regulatory subunit...

  20. HUMAN ACTIVITY MONITORING USING SMARTPHONE

    OpenAIRE

    TOKALA, SAI SUJIT; ROKALA, RANADEEP

    2014-01-01

    The main aim of the project is to develop an algorithm which will classify the activity performed by a human who is carrying a smart phone. The day to day life made humans very busy at work and during daily activities, mostly elderly people who are at home have an important need to monitor their activity by others when they are alone, if they are inactive for a long time without movement, or in some situations like if they have fallen down, became unconscious for sometime or seized with a car...

  1. Analysis of the protein-protein interactions between the human acidic ribosomal P-proteins: evaluation by the two hybrid system

    DEFF Research Database (Denmark)

    Tchórzewski, M; Boldyreff, B; Issinger, O

    2000-01-01

    The surface acidic ribosomal proteins (P-proteins), together with ribosomal core protein P0 form a multimeric lateral protuberance on the 60 S ribosomal subunit. This structure, also called stalk, is important for efficient translational activity of the ribosome. In order to shed more light...... forms the 60 S ribosomal stalk: P0-(P1/P2)(2). Additionally, mutual interactions among human and yeast P-proteins were analyzed. Heterodimer formation could be observed between human P2 and yeast P1 proteins....

  2. Radioimmunoassay of human plasma protein C

    International Nuclear Information System (INIS)

    Wang Bocheng; Li Jinquan; Jing Jian; Zhang Manda

    1995-01-01

    A radioimmunoassay method for the measurement of human plasma protein C (PC) is established. PC was isolated and purified from human plasma. The antisera against PC was obtained by immunizing rabbits. Iodination of PC was carried out with chroramine-T. The sensitivity was 3.94% μg/L, and the assay covered 6.25∼1024 μg/L for PC. The intra-assay and inter-assay CV were 4.4% and 9.68% respectively, with a recovery rate of 104.28%. There was no cross reaction with factor II. The normal value was 3.84 +- 0.34 mg/L in 36 normal persons. Value of 1.03 +-0.41 mg/L was found in 16 patients with fulminating hepatitis complicated with coagulation disturbance. It is an effective approach for the diagnosis of hereditary or acquired PC deficiency and also for the study of thrombotic diseases

  3. Canine distemper virus neutralization activity is low in human serum and it is sensitive to an amino acid substitution in the hemagglutinin protein.

    Science.gov (United States)

    Zhang, Xinsheng; Wallace, Olivia L; Domi, Arban; Wright, Kevin J; Driscoll, Jonathan; Anzala, Omu; Sanders, Eduard J; Kamali, Anatoli; Karita, Etienne; Allen, Susan; Fast, Pat; Gilmour, Jill; Price, Matt A; Parks, Christopher L

    2015-08-01

    Serum was analyzed from 146 healthy adult volunteers in eastern Africa to evaluate measles virus (MV) and canine distemper virus (CDV) neutralizing antibody (nAb) prevalence and potency. MV plaque reduction neutralization test (PRNT) results indicated that all sera were positive for MV nAbs. Furthermore, the 50% neutralizing dose (ND50) for the majority of sera corresponded to antibody titers induced by MV vaccination. CDV nAbs titers were low and generally were detected in sera with high MV nAb titers. A mutant CDV was generated that was less sensitive to neutralization by human serum. The mutant virus genome had 10 nucleotide substitutions, which coded for single amino acid substitutions in the fusion (F) and hemagglutinin (H) glycoproteins and two substitutions in the large polymerase (L) protein. The H substitution occurred in a conserved region involved in receptor interactions among morbilliviruses, implying that this region is a target for cross-reactive neutralizing antibodies. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Identification of actin binding protein, ABP-280, as a binding partner of human Lnk adaptor protein.

    Science.gov (United States)

    He, X; Li, Y; Schembri-King, J; Jakes, S; Hayashi, J

    2000-08-01

    Human Lnk (hLnk) is an adaptor protein with multiple functional domains that regulates T cell activation signaling. In order to identify cellular Lnk binding partners, a yeast two-hybrid screening of human spleen cDNA library was carried out using human hLnk as bait. A polypeptide sequence identical to the C-terminal segment of the actin binding protein (ABP-280) was identified as a hLnk binding protein. The expressed hLnk and the FLAG tagged C-terminal 673 amino acid residues of ABP-280 or the endogenous ABP-280 in COS-7 cells could be co-immunoprecipitated using antibodies either to hLnk, FLAG or ABP-280, respectively. Furthermore, immunofluorescence confocal microscope showed that hLnk and ABP-280 co-localized at the plasma membrane and at juxtanuclear region of COS-7 cells. In Jurkat cells, the endogenous hLnk also associates with the endogenous ABP-280 indicating that the association of these two proteins is physiological. The interacting domains of both proteins were mapped using yeast two-hybrid assays. Our results indicate that hLnk binds to the residues 2006-2454 (repeats 19-23C) of ABP-280. The domain in hLnk that associates with ABP-280 was mapped to an interdomain region of 56 amino acids between pleckstrin homology and Src homology 2 domains. These results suggest that hLnk may exert its regulatory role through its association with ABP-280.

  5. A novel role for a major component of the vitamin D axis: vitamin D binding protein-derived macrophage activating factor induces human breast cancer cell apoptosis through stimulation of macrophages.

    Science.gov (United States)

    Thyer, Lynda; Ward, Emma; Smith, Rodney; Fiore, Maria Giulia; Magherini, Stefano; Branca, Jacopo J V; Morucci, Gabriele; Gulisano, Massimo; Ruggiero, Marco; Pacini, Stefania

    2013-07-08

    The role of vitamin D in maintaining health appears greater than originally thought, and the concept of the vitamin D axis underlines the complexity of the biological events controlled by biologically active vitamin D (1,25(OH)(2)D3), its two binding proteins that are the vitamin D receptor (VDR) and the vitamin D-binding protein-derived macrophage activating factor (GcMAF). In this study we demonstrate that GcMAF stimulates macrophages, which in turn attack human breast cancer cells, induce their apoptosis and eventually phagocytize them. These results are consistent with the observation that macrophages infiltrated implanted tumors in mice after GcMAF injections. In addition, we hypothesize that the last 23 hydrophobic amino acids of VDR, located at the inner part of the plasma membrane, interact with the first 23 hydrophobic amino acids of the GcMAF located at the external part of the plasma membrane. This allows 1,25(OH)(2)D3 and oleic acid to become sandwiched between the two vitamin D-binding proteins, thus postulating a novel molecular mode of interaction between GcMAF and VDR. Taken together, these results support and reinforce the hypothesis that GcMAF has multiple biological activities that could be responsible for its anti-cancer effects, possibly through molecular interaction with the VDR that in turn is responsible for a multitude of non-genomic as well as genomic effects.

  6. A Novel Role for a Major Component of the Vitamin D Axis: Vitamin D Binding Protein-Derived Macrophage Activating Factor Induces Human Breast Cancer Cell Apoptosis through Stimulation of Macrophages

    Directory of Open Access Journals (Sweden)

    Marco Ruggiero

    2013-07-01

    Full Text Available The role of vitamin D in maintaining health appears greater than originally thought, and the concept of the vitamin D axis underlines the complexity of the biological events controlled by biologically active vitamin D (1,25(OH(2D3, its two binding proteins that are the vitamin D receptor (VDR and the vitamin D-binding protein-derived macrophage activating factor (GcMAF. In this study we demonstrate that GcMAF stimulates macrophages, which in turn attack human breast cancer cells, induce their apoptosis and eventually phagocytize them. These results are consistent with the observation that macrophages infiltrated implanted tumors in mice after GcMAF injections. In addition, we hypothesize that the last 23 hydrophobic amino acids of VDR, located at the inner part of the plasma membrane, interact with the first 23 hydrophobic amino acids of the GcMAF located at the external part of the plasma membrane. This al1ows 1,25(OH(2D3 and oleic acid to become sandwiched between the two vitamin D-binding proteins, thus postulating a novel molecular mode of interaction between GcMAF and VDR. Taken together, these results support and reinforce the hypothesis that GcMAF has multiple biological activities that could be responsible for its anti-cancer effects, possibly through molecular interaction with the VDR that in turn is responsible for a multitude of non-genomic as well as genomic effects.

  7. Protein Kinase A Regulatory Subunits in Human Adipose Tissue

    Science.gov (United States)

    Mantovani, Giovanna; Bondioni, Sara; Alberti, Luisella; Gilardini, Luisa; Invitti, Cecilia; Corbetta, Sabrina; Zappa, Marco A.; Ferrero, Stefano; Lania, Andrea G.; Bosari, Silvano; Beck-Peccoz, Paolo; Spada, Anna

    2009-01-01

    OBJECTIVE—In human adipocytes, the cAMP-dependent pathway mediates signals originating from β-adrenergic activation, thus playing a key role in the regulation of important metabolic processes, i.e., lipolysis and thermogenesis. Cyclic AMP effects are mainly mediated by protein kinase A (PKA), whose R2B regulatory isoform is the most expressed in mouse adipose tissue, where it protects against diet-induced obesity and fatty liver development. The aim of the study was to investigate possible differences in R2B expression, PKA activity, and lipolysis in adipose tissues from obese and nonobese subjects. RESEARCH DESIGN AND METHODS—The expression of the different PKA regulatory subunits was evaluated by immunohistochemistry, Western blot, and real-time PCR in subcutaneous and visceral adipose tissue samples from 20 nonobese and 67 obese patients. PKA activity and glycerol release were evaluated in total protein extract and adipocytes isolated from fresh tissue samples, respectively. RESULTS—Expression techniques showed that R2B was the most abundant regulatory protein, both at mRNA and protein level. Interestingly, R2B mRNA levels were significantly lower in both subcutaneous and visceral adipose tissues from obese than nonobese patients and negatively correlated with BMI, waist circumference, insulin levels, and homeostasis model assessment of insulin resistance. Moreover, both basal and stimulated PKA activity and glycerol release were significantly lower in visceral adipose tissue from obese patients then nonobese subjects. CONCLUSIONS—Our results first indicate that, in human adipose tissue, there are important BMI-related differences in R2B expression and PKA activation, which might be included among the multiple determinants involved in the different lipolytic response to β-adrenergic activation in obesity. PMID:19095761

  8. A Quest for Missing Proteins : update 2015 on Chromosome-Centric Human Proteome Project

    NARCIS (Netherlands)

    Horvatovich, Péter; Lundberg, Emma K; Chen, Yu-Ju; Sung, Ting-Yi; He, Fuchu; Nice, Edouard C; Goode, Robert J A; Yu, Simon; Ranganathan, Shoba; Baker, Mark S; Domont, Gilberto B; Velasquez, Erika; Li, Dong; Liu, Siqi; Wang, Quanhui; He, Qing-Yu; Menon, Rajasree; Guan, Yuanfang; Corrales, Fernando Jose; Segura, Victor; Casal, José Ignacio; Pascual-Montano, Alberto; Albar, Juan Pablo; Fuentes, Manuel; Gonzalez-Gonzalez, Maria; Diez, Paula; Ibarrola, Nieves; Degano, Rosa M; Mohammed, Yassene; Borchers, Christoph H; Urbani, Andrea; Soggiu, Alessio; Yamamoto, Tadashi; Archakov, Alexander I; Ponomarenko, Elena; Lisitsa, Andrey V; Lichti, Cheryl F; Mostovenko, Ekaterina; Kroes, Roger A; Rezeli, Melinda; Vegvari, Akos; Fehniger, Thomas E; Bischoff, Rainer; Vizcaíno, Juan Antonio; Deutsch, Eric W; Lane, Lydie; Nilsson, Carol L; Marko-Varga, György; Omenn, Gilbert S; Jeong, Seul-Ki; Cho, Jin-Young; Paik, Young-Ki; Hancock, William S

    2015-01-01

    This paper summarizes the recent activities of the Chromosome-Centric Human Proteome Project (C-HPP) consortium, which develops new technologies to identify yet-to-be annotated proteins (termed "missing proteins") in biological samples that lack sufficient experimental evidence at the protein level

  9. Barcoding heat shock proteins to human diseases : looking beyond the heat shock response

    NARCIS (Netherlands)

    Kakkar, Vaishali; Meister-Broekema, Melanie; Minoia, Melania; Carra, Serena; Kampinga, Harm H.

    There are numerous human diseases that are associated with protein misfolding and the formation of toxic protein aggregates. Activating the heat shock response (HSR) - and thus generally restoring the disturbed protein homeostasis associated with such diseases - has often been suggested as a

  10. The SANT2 domain of the murine tumor cell DnaJ-like protein 1 human homologue interacts with alpha1-antichymotrypsin and kinetically interferes with its serpin inhibitory activity.

    Science.gov (United States)

    Kroczynska, Barbara; Evangelista, Christina M; Samant, Shalaka S; Elguindi, Ebrahim C; Blond, Sylvie Y

    2004-03-19

    The murine tumor cell DnaJ-like protein 1 or MTJ1/ERdj1 is a membrane J-domain protein enriched in microsomal and nuclear fractions. We previously showed that its lumenal J-domain stimulates the ATPase activity of the molecular chaperone BiP/GRP78 (Chevalier, M., Rhee, H., Elguindi, E. C., and Blond, S. Y. (2000) J. Biol. Chem. 275, 19620-19627). MTJ1/ERdj1 also contains a large carboxyl-terminal cytosolic extension composed of two tryptophan-mediated repeats or SANT domains for which the function(s) is unknown. Here we describe the cloning of the human homologue HTJ1 and its interaction with alpha(1)-antichymotrypsin (ACT), a member of the serine proteinase inhibitor (serpin) family. The interaction was initially identified in a two-hybrid screening and further confirmed in vitro by dot blots, native electrophoresis, and fluorescence studies. The second SANT domain of HTJ1 (SANT2) was found to be sufficient for binding to ACT, both in yeast and in vitro. Single tryptophan-alanine substitutions at two strictly conserved residues significantly (Trp-497) or totally (Trp-520) abolished the interaction with ACT. SANT2 binds to human ACT with an intrinsic affinity equal to 0.5 nm. Preincubation of ACT with nearly stoichiometric concentrations of SANT2 wild-type but not SANT2: W520A results in an apparent loss of ACT inhibitory activity toward chymotrypsin. Kinetic analysis indicates that the formation of the covalent inhibitory complex ACT-chymotrypsin is significantly delayed in the presence of SANT2 with no change on the catalytic efficiency of the enzyme. This work demonstrates for the first time that the SANT2 domain of MTJ1/HTJ1/ERdj1 mediates stable and high affinity protein-protein interactions.

  11. Matrix metalloproteinase-2 and -9 are induced differently by metal nanoparticles in human monocytes: The role of oxidative stress and protein tyrosine kinase activation

    International Nuclear Information System (INIS)

    Wan Rong; Mo Yiqun; Zhang Xing; Chien Sufan; Tollerud, David J.; Zhang Qunwei

    2008-01-01

    Recently, many studies have shown that nanoparticles can translocate from the lungs to the circulatory system. As a particulate foreign body, nanoparticles could induce host responses such as reactive oxygen species (ROS) generation, inflammatory cytokine and matrix metalloproteinase (MMP) release which play a major role in tissue destruction and remodeling. However, the direct effects of nanoparticles on leukocytes, especially monocytes, are still unclear. The objective of the present study was to compare the ability of Nano-Co and Nano-TiO 2 to cause alteration of transcription and activity of MMPs and to explore possible mechanisms. We hypothesized that non-toxic doses of some transition metal nanoparticles stimulate an imbalance of MMP/TIMP that cause MMP production that may contribute to their health effects. To test this hypothesis, U937 cells were treated with Nano-Co and Nano-TiO 2 and cytotoxic effects and ROS generation were measured. The alteration of MMP-2 and MMP-9 expression and activity of MMP-2 and MMP-9 after exposure to these metal nanoparticles were subsequently determined. To investigate the potential signaling pathways involved in the Nano-Co-induced MMP activation, the ROS scavengers or inhibitors, AP-1 inhibitor, and protein tyrosine kinase (PTK) inhibitors were also used to pre-treat U937 cells. Our results demonstrated that exposure of U937 cells to Nano-Co, but not to Nano-TiO 2 , at a dose that does not cause cytotoxicity, resulted in ROS generation and up-regulation of MMP-2 and MMP-9 mRNA expression .. Our results also showed dose- and time-related increases in pro-MMP-2 and pro-MMP-9 gelatinolytic activities in conditioned media after exposure of U937 cells to Nano-Co, but not to Nano-TiO 2 . Nano-Co-induced pro-MMP-2 and pro-MMP-9 activity increases were inhibited by pre-treatment with ROS scavengers or inhibitors. We also demonstrated dose- and time-related decreases in tissue inhibitors of metalloproteinases 2 (TIMP-2) in U937 cells

  12. Enzymatic characterization of a human acyltransferase activity.

    Directory of Open Access Journals (Sweden)

    Akihiko Ozawa

    Full Text Available Non-histone protein acylation is increasingly recognized as an important posttranslational modification, but little is known as to the biochemical properties of protein serine acylating enzymes.We here report that we have identified a metal-stimulated serine octanoyltransferase activity in microsomes from human erythroleukemic (HEL cells. The HEL acylating enzyme was linear with respect to time and protein, exhibited a neutral pH optimum (stimulated by cobalt and zinc, and inhibited by chelating reagents. Hydroxylamine treatment removed most, but not all, of the attached radioactivity. A salt extract of microsomal membranes contained the major portion of enzyme activity, indicating that this acyltransferase is not an integral membrane protein. Sucrose density fractionation showed that the acyltransferase activity is concentrated in the endoplasmic reticulum. In competition experiments, the acyltransferase was well inhibited by activated forms of fatty acids containing at least eight to fourteen carbons, but not by acetyl CoA. The zinc-stimulated HEL acyltransferase did not octanoylate proenkephalin, proopiomelanocortin, His-tagged proghrelin, or proghrelin lacking the amino-terminal His-tag stub of Gly-Ala-Met. The peptides des-acyl ghrelin and ACTH were also not acylated; however, des-acyl ghrelin containing the N-terminal tripeptide Gly-Ala-Met was acylated. Mutagenesis studies indicated a requirement for serine five residues from the amino terminus, reminiscent of myristoyl transferase, but not of ghrelin acylation. However, recombinant myristoyl transferase could not recapitulate the hydroxylamine sensitivity, zinc-stimulation, nor EDTA inhibition obtained with HEL acyltransferase, properties preserved in the HEL cell enzyme purified through four sequential chromatographic steps.In conclusion, our data demonstrate the presence of a zinc-stimulated acyltransferase activity concentrated in the endoplasmic reticulum in HEL cells which is likely

  13. Specific binding of [alpha-32P]GTP to cytosolic and membrane-bound proteins of human platelets correlates with the activation of phospholipase C

    International Nuclear Information System (INIS)

    Lapetina, E.G.; Reep, B.R.

    1987-01-01

    We have assessed the binding of [alpha- 32 P]GTP to platelet proteins from cytosolic and membrane fractions. Proteins were separated by NaDodSO 4 /PAGE and electrophoretically transferred to nitrocellulose. Incubation of the nitrocellulose blots with [alpha- 32 P]GTP indicated the presence of specific and distinct GTP-binding proteins in cytosol and membranes. Binding was prevented by 10-100 nM GTP and by 100 nM guanosine 5'-[gamma-thio]triphosphate (GTP[gamma S]) or GDP; binding was unaffected by 1 nM-1 microM ATP. One main GTP-binding protein (29.5 kDa) was detected in the membrane fraction, while three others (29, 27, and 21 kDa) were detected in the soluble fraction. Two cytosolic GTP-binding proteins (29 and 27 kDa) were degraded by trypsin; another cytosolic protein (21 kDa) and the membrane-bound protein (29.5 kDa) were resistant to the action of trypsin. Treatment of intact platelets with trypsin or thrombin, followed by lysis and fractionation, did not affect the binding of [alpha- 32 P]GTP to the membrane-bound protein. GTP[gamma S] still stimulated phospholipase C in permeabilized platelets already preincubated with trypsin. This suggests that trypsin-resistant GTP-binding proteins might regulate phospholipase C stimulated by GTP[gamma S

  14. Solution structure of the human signaling protein RACK1

    Directory of Open Access Journals (Sweden)

    Papa Priscila F

    2010-06-01

    Full Text Available Abstract Background The adaptor protein RACK1 (receptor of activated kinase 1 was originally identified as an anchoring protein for protein kinase C. RACK1 is a 36 kDa protein, and is composed of seven WD repeats which mediate its protein-protein interactions. RACK1 is ubiquitously expressed and has been implicated in diverse cellular processes involving: protein translation regulation, neuropathological processes, cellular stress, and tissue development. Results In this study we performed a biophysical analysis of human RACK1 with the aim of obtaining low resolution structural information. Small angle X-ray scattering (SAXS experiments demonstrated that human RACK1 is globular and monomeric in solution and its low resolution structure is strikingly similar to that of an homology model previously calculated by us and to the crystallographic structure of RACK1 isoform A from Arabidopsis thaliana. Both sedimentation velocity and sedimentation equilibrium analytical ultracentrifugation techniques showed that RACK1 is predominantly a monomer of around 37 kDa in solution, but also presents small amounts of oligomeric species. Moreover, hydrodynamic data suggested that RACK1 has a slightly asymmetric shape. The interaction of RACK1 and Ki-1/57 was tested by sedimentation equilibrium. The results suggested that the association between RACK1 and Ki-1/57(122-413 follows a stoichiometry of 1:1. The binding constant (KB observed for RACK1-Ki-1/57(122-413 interaction was of around (1.5 ± 0.2 × 106 M-1 and resulted in a dissociation constant (KD of (0.7 ± 0.1 × 10-6 M. Moreover, the fluorescence data also suggests that the interaction may occur in a cooperative fashion. Conclusion Our SAXS and analytical ultracentrifugation experiments indicated that RACK1 is predominantly a monomer in solution. RACK1 and Ki-1/57(122-413 interact strongly under the tested conditions.

  15. In vitro study of proteins surface activity by tritium probe

    International Nuclear Information System (INIS)

    Chernysheva, M.G.; Badun, G.A.

    2010-01-01

    A new technique for in vitro studies of biomacromolecules interactions, their adsorption at aqueous/organic liquid interfaces and distribution in the bulk of liquid/liquid systems was developed. The method includes (1) tritium labeling of biomolecules by tritium thermal activation method and (2) scintillation phase step with organic phase, which can be concerned as a model of cellular membrane. Two globular proteins lysozyme and human serum albumin tested. We have determined the conditions of tritium labeling when labeled by-products can be easy separated by means of dialysis and size-exclusion chromatography. Scintillation phase experiments were conducted for three types of organic liquids. Thus, the influences of the nature of organic phase on proteins adsorption and its distribution in the bulk of aqueous/organic liquid system were determined. It was found that proteins possess high surface activity at aqueous/organic liquid interface. Furthermore, values of hydrophobicity of globular proteins were found by the experiment. (author)

  16. Insight into bacterial virulence mechanisms against host immune response via the Yersinia pestis-human protein-protein interaction network.

    Science.gov (United States)

    Yang, Huiying; Ke, Yuehua; Wang, Jian; Tan, Yafang; Myeni, Sebenzile K; Li, Dong; Shi, Qinghai; Yan, Yanfeng; Chen, Hui; Guo, Zhaobiao; Yuan, Yanzhi; Yang, Xiaoming; Yang, Ruifu; Du, Zongmin

    2011-11-01

    A Yersinia pestis-human protein interaction network is reported here to improve our understanding of its pathogenesis. Up to 204 interactions between 66 Y. pestis bait proteins and 109 human proteins were identified by yeast two-hybrid assay and then combined with 23 previously published interactions to construct a protein-protein interaction network. Topological analysis of the interaction network revealed that human proteins targeted by Y. pestis were significantly enriched in the proteins that are central in the human protein-protein interaction network. Analysis of this network showed that signaling pathways important for host immune responses were preferentially targeted by Y. pestis, including the pathways involved in focal adhesion, regulation of cytoskeleton, leukocyte transendoepithelial migration, and Toll-like receptor (TLR) and mitogen-activated protein kinase (MAPK) signaling. Cellular pathways targeted by Y. pestis are highly relevant to its pathogenesis. Interactions with host proteins involved in focal adhesion and cytoskeketon regulation pathways could account for resistance of Y. pestis to phagocytosis. Interference with TLR and MAPK signaling pathways by Y. pestis reflects common characteristics of pathogen-host interaction that bacterial pathogens have evolved to evade host innate immune response by interacting with proteins in those signaling pathways. Interestingly, a large portion of human proteins interacting with Y. pestis (16/109) also interacted with viral proteins (Epstein-Barr virus [EBV] and hepatitis C virus [HCV]), suggesting that viral and bacterial pathogens attack common cellular functions to facilitate infections. In addition, we identified vasodilator-stimulated phosphoprotein (VASP) as a novel interaction partner of YpkA and showed that YpkA could inhibit in vitro actin assembly mediated by VASP.

  17. When Heterotrimeric G Proteins Are Not Activated by G Protein-Coupled Receptors: Structural Insights and Evolutionary Conservation.

    Science.gov (United States)

    DiGiacomo, Vincent; Marivin, Arthur; Garcia-Marcos, Mikel

    2018-01-23

    Heterotrimeric G proteins are signal-transducing switches conserved across eukaryotes. In humans, they work as critical mediators of intercellular communication in the context of virtually any physiological process. While G protein regulation by G protein-coupled receptors (GPCRs) is well-established and has received much attention, it has become recently evident that heterotrimeric G proteins can also be activated by cytoplasmic proteins. However, this alternative mechanism of G protein regulation remains far less studied than GPCR-mediated signaling. This Viewpoint focuses on recent advances in the characterization of a group of nonreceptor proteins that contain a sequence dubbed the "Gα-binding and -activating (GBA) motif". So far, four proteins present in mammals [GIV (also known as Girdin), DAPLE, CALNUC, and NUCB2] and one protein in Caenorhabditis elegans (GBAS-1) have been described as possessing a functional GBA motif. The GBA motif confers guanine nucleotide exchange factor activity on Gαi subunits in vitro and activates G protein signaling in cells. The importance of this mechanism of signal transduction is highlighted by the fact that its dysregulation underlies human diseases, such as cancer, which has made the proteins attractive new candidates for therapeutic intervention. Here we discuss recent discoveries on the structural basis of GBA-mediated activation of G proteins and its evolutionary conservation and compare them with the better-studied mechanism mediated by GPCRs.

  18. Stress-induced activation of protein kinase CK2 by direct interaction with p38 mitogen-activated protein kinase

    DEFF Research Database (Denmark)

    Sayed, M; Kim, S O; Salh, B S

    2000-01-01

    Protein kinase CK2 has been implicated in the regulation of a wide range of proteins that are important in cell proliferation and differentiation. Here we demonstrate that the stress signaling agents anisomycin, arsenite, and tumor necrosis factor-alpha stimulate the specific enzyme activity of CK2...... in the human cervical carcinoma HeLa cells by up to 8-fold, and this could be blocked by the p38 MAP kinase inhibitor SB203580. We show that p38alpha MAP kinase, in a phosphorylation-dependent manner, can directly interact with the alpha and beta subunits of CK2 to activate the holoenzyme through what appears...

  19. Physical activity and human health

    Directory of Open Access Journals (Sweden)

    Paulina Wojciechowska

    2015-01-01

    Full Text Available Introduction: The dynamic development of the automotive industry, transport, and the media means that human life has become much easier. At the same time, the comfortable living conditions have decreased physical activity. Biologically conditioned, the need of activity has been minimised by the ever-increasing pace of life. As a result, it may lead to the loss of physical and mental health. Active recreation is not only an excellent source of activity, but also a source of satisfaction. Youths and adults should therefore spend their free time primarily on various forms of physical activity. Aim of the research : To evaluate the physical fitness of students who regularly practice physical exercise, those who occasionally practice, and those not practicing any form of physical activity. Material and methods : In the research we used a questionnaire of the Ruffier test and an orthostatic test. The study involved a group of 15 people aged 20–25 years. Participation in the study was entirely voluntary and anonymous. The study group consisted only of women. Results obtained from the questionnaire survey were fully reflected during exercise tests performed. Results and conclusions: Only regularly practiced physical activity has an effect on our body. Regular exercise increases our body’s physical capacity. Activity is the best means of prevention of lifestyle diseases. Youths and adults should spend their free time mainly doing various forms of physical activity.

  20. Development of human protein reference database as an initial platform for approaching systems biology in humans

    DEFF Research Database (Denmark)

    Peri, Suraj; Navarro, J Daniel; Amanchy, Ramars

    2003-01-01

    Human Protein Reference Database (HPRD) is an object database that integrates a wealth of information relevant to the function of human proteins in health and disease. Data pertaining to thousands of protein-protein interactions, posttranslational modifications, enzyme/substrate relationships...

  1. Membrane Recruitment of the Non-receptor Protein GIV/Girdin (Gα-interacting, Vesicle-associated Protein/Girdin) Is Sufficient for Activating Heterotrimeric G Protein Signaling.

    Science.gov (United States)

    Parag-Sharma, Kshitij; Leyme, Anthony; DiGiacomo, Vincent; Marivin, Arthur; Broselid, Stefan; Garcia-Marcos, Mikel

    2016-12-30

    GIV (aka Girdin) is a guanine nucleotide exchange factor that activates heterotrimeric G protein signaling downstream of RTKs and integrins, thereby serving as a platform for signaling cascade cross-talk. GIV is recruited to the cytoplasmic tail of receptors upon stimulation, but the mechanism of activation of its G protein regulatory function is not well understood. Here we used assays in humanized yeast models and G protein activity biosensors in mammalian cells to investigate the role of GIV subcellular compartmentalization in regulating its ability to promote G protein signaling. We found that in unstimulated cells GIV does not co-fractionate with its substrate G protein Gα i3 on cell membranes and that constitutive membrane anchoring of GIV in yeast cells or rapid membrane translocation in mammalian cells via chemically induced dimerization leads to robust G protein activation. We show that membrane recruitment of the GIV "Gα binding and activating" motif alone is sufficient for G protein activation and that it does not require phosphomodification. Furthermore, we engineered a synthetic protein to show that recruitment of the GIV "Gα binding and activating" motif to membranes via association with active RTKs, instead of via chemically induced dimerization, is also sufficient for G protein activation. These results reveal that recruitment of GIV to membranes in close proximity to its substrate G protein is a major mechanism responsible for the activation of its G protein regulatory function. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. The shunt from the cyclooxygenase to lipoxygenase pathway in human osteoarthritic subchondral osteoblasts is linked with a variable expression of the 5-lipoxygenase-activating protein.

    Science.gov (United States)

    Maxis, Kelitha; Delalandre, Aline; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Duval, Nicolas; Lajeunesse, Daniel

    2006-01-01

    Osteoarthritis (OA) is characterized by articular cartilage degradation and hypertrophic bone changes with osteophyte formation and abnormal bone remodeling. Two groups of OA patients were identified via the production of variable and opposite levels of prostaglandin E2 (PGE2) or leukotriene B4 (LTB4) by subchondral osteoblasts, PGE2 levels discriminating between low and high subgroups. We studied whether the expression of 5-lipoxygenase (5-LO) or 5-LO-activating protein (FLAP) is responsible for the shunt from prostaglandins to leukotrienes. FLAP mRNA levels varied in low and high OA groups compared with normal, whereas mRNA levels of 5-LO were similar in all osteoblasts. Selective inhibition of cyclooxygenase-2 (COX-2) with NS-398-stimulated FLAP expression in the high OA osteoblasts subgroup, whereas it was without effect in the low OA osteoblasts subgroup. The addition of PGE2 to the low OA osteoblasts subgroup decreased FLAP expression but failed to affect it in the high OA osteoblasts subgroup. LTB4 levels in OA osteoblasts were stimulated about twofold by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plus transforming growth factor-beta (TGF-beta), a situation corresponding to their effect on FLAP mRNA levels. Treatments with 1,25(OH)2D3 and TGF-beta also modulated PGE2 production. TGF-beta stimulated PGE2 production in both OA osteoblast groups, whereas 1,25(OH)2D3 alone had a limited effect but decreased the effect of TGF-beta in the low OA osteoblasts subgroup. This modulation of PGE2 production was mirrored by the synthesis of COX-2. IL-18 levels were only slightly increased in a subgroup of OA osteoblasts compared with normal; however, no relationship was observed overall between IL-18 and PGE2 levels in normal and OA osteoblasts. These results suggest that the shunt from the production of PGE2 to LTB4 is through regulation of the expression of FLAP, not 5-LO, in OA osteoblasts. The expression of FLAP in OA osteoblasts is also modulated differently by 1,25(OH

  3. Gains of ubiquitylation sites in highly conserved proteins in the human lineage

    Directory of Open Access Journals (Sweden)

    Kim Dong Seon

    2012-11-01

    Full Text Available Abstract Background Post-translational modification of lysine residues of specific proteins by ubiquitin modulates the degradation, localization, and activity of these target proteins. Here, we identified gains of ubiquitylation sites in highly conserved regions of human proteins that occurred during human evolution. Results We analyzed human ubiquitylation site data and multiple alignments of orthologous mammalian proteins including those from humans, primates, other placental mammals, opossum, and platypus. In our analysis, we identified 281 ubiquitylation sites in 252 proteins that first appeared along the human lineage during primate evolution: one protein had four novel sites; four proteins had three sites each; 18 proteins had two sites each; and the remaining 229 proteins had one site each. PML, which is involved in neurodevelopment and neurodegeneration, acquired three sites, two of which have been reported to be involved in the degradation of PML. Thirteen human proteins, including ERCC2 (also known as XPD and NBR1, gained human-specific ubiquitylated lysines after the human-chimpanzee divergence. ERCC2 has a Lys/Gln polymorphism, the derived (major allele of which confers enhanced DNA repair capacity and reduced cancer risk compared with the ancestral (minor allele. NBR1 and eight other proteins that are involved in the human autophagy protein interaction network gained a novel ubiquitylation site. Conclusions The gain of novel ubiquitylation sites could be involved in the evolution of protein degradation and other regulatory networks. Although gains of ubiquitylation sites do not necessarily equate to adaptive evolution, they are useful candidates for molecular functional analyses to identify novel advantageous genetic modifications and innovative phenotypes acquired during human evolution.

  4. Interaction of human biliverdin reductase with Akt/protein kinase B and phosphatidylinositol-dependent kinase 1 regulates glycogen synthase kinase 3 activity: a novel mechanism of Akt activation

    OpenAIRE

    Miralem, Tihomir; Lerner-Marmarosh, Nicole; Gibbs, Peter E. M.; Jenkins, Jermaine L.; Heimiller, Chelsea; Maines, Mahin D.

    2016-01-01

    Biliverdin reductase A (BVR) and Akt isozymes have overlapping pleiotropic functions in the insulin/PI3K/MAPK pathway. Human BVR (hBVR) also reduces the hemeoxygenase activity product biliverdin to bilirubin and is directly activated by insulin receptor kinase (IRK). Akt isoenzymes (Akt1–3) are downstream of IRK and are activated by phosphatidylinositol-dependent kinase 1 (PDK1) phosphorylating T308 before S473 autophosphorylation. Akt (RxRxxSF) and PDK1 (RFxFPxFS) binding motifs are present ...

  5. Activated Protein C Drives the Hyperfibrinolysis of Acute Traumatic Coagulopathy.

    Science.gov (United States)

    Davenport, Ross A; Guerreiro, Maria; Frith, Daniel; Rourke, Claire; Platton, Sean; Cohen, Mitchell; Pearse, Rupert; Thiemermann, Chris; Brohi, Karim

    2017-01-01

    Major trauma is a leading cause of morbidity and mortality worldwide with hemorrhage accounting for 40% of deaths. Acute traumatic coagulopathy exacerbates bleeding, but controversy remains over the degree to which inhibition of procoagulant pathways (anticoagulation), fibrinogen loss, and fibrinolysis drive the pathologic process. Through a combination of experimental study in a murine model of trauma hemorrhage and human observation, the authors' objective was to determine the predominant pathophysiology of acute traumatic coagulopathy. First, a prospective cohort study of 300 trauma patients admitted to a single level 1 trauma center with blood samples collected on arrival was performed. Second, a murine model of acute traumatic coagulopathy with suppressed protein C activation via genetic mutation of thrombomodulin was used. In both studies, analysis for coagulation screen, activated protein C levels, and rotational thromboelastometry (ROTEM) was performed. In patients with acute traumatic coagulopathy, the authors have demonstrated elevated activated protein C levels with profound fibrinolytic activity and early depletion of fibrinogen. Procoagulant pathways were only minimally inhibited with preservation of capacity to generate thrombin. Compared to factors V and VIII, proteases that do not undergo activated protein C-mediated cleavage were reduced but maintained within normal levels. In transgenic mice with reduced capacity to activate protein C, both fibrinolysis and fibrinogen depletion were significantly attenuated. Other recognized drivers of coagulopathy were associated with less significant perturbations of coagulation. Activated protein C-associated fibrinolysis and fibrinogenolysis, rather than inhibition of procoagulant pathways, predominate in acute traumatic coagulopathy. In combination, these findings suggest a central role for the protein C pathway in acute traumatic coagulopathy and provide new translational opportunities for management of

  6. Petunia nectar proteins have ribonuclease activity.

    Science.gov (United States)

    Hillwig, Melissa S; Liu, Xiaoteng; Liu, Guangyu; Thornburg, Robert W; Macintosh, Gustavo C

    2010-06-01

    Plants requiring an insect pollinator often produce nectar as a reward for the pollinator's visitations. This rich secretion needs mechanisms to inhibit microbial growth. In Nicotiana spp. nectar, anti-microbial activity is due to the production of hydrogen peroxide. In a close relative, Petunia hybrida, limited production of hydrogen peroxide was found; yet petunia nectar still has anti-bacterial properties, suggesting that a different mechanism may exist for this inhibition. The nectar proteins of petunia plants were compared with those of ornamental tobacco and significant differences were found in protein profiles and function between these two closely related species. Among those proteins, RNase activities unique to petunia nectar were identified. The genes corresponding to four RNase T2 proteins from Petunia hybrida that show unique expression patterns in different plant tissues were cloned. Two of these enzymes, RNase Phy3 and RNase Phy4 are unique among the T2 family and contain characteristics similar to both S- and S-like RNases. Analysis of amino acid patterns suggest that these proteins are an intermediate between S- and S-like RNases, and support the hypothesis that S-RNases evolved from defence RNases expressed in floral parts. This is the first report of RNase activities in nectar.

  7. Human Serum Protein-Bound iodine and Protein Fractions at ...

    African Journals Online (AJOL)

    Iodine profile of Nigerians at different ages in both sexes and in pregnant women, and under narcotic influence, such as alcoholism, cigarette smoking and marijuana addiction were studied. Their serum total protein, albumin and globulin concentrations were also determined. Results of the study showed that serum protein ...

  8. Efficient activation of T cells by human monocyte-derived dendritic cells (HMDCs pulsed with Coxiella burnetii outer membrane protein Com1 but not by HspB-pulsed HMDCs

    Directory of Open Access Journals (Sweden)

    Wang Xile

    2011-09-01

    Full Text Available Abstract Background Coxiella burnetii is an obligate intracellular bacterium and the etiologic agent of Q fever; both coxiella outer membrane protein 1 (Com1 and heat shock protein B (HspB are its major immunodominant antigens. It is not clear whether Com1 and HspB have the ability to mount immune responses against C. burnetii infection. Results The recombinant proteins Com1 and HspB were applied to pulse human monocyte-derived dendritic cells (HMDCs, and the pulsed HMDCs were used to stimulate isogenic T cells. Com1-pulsed HMDCs expressed substantially higher levels of surface molecules (CD83, CD40, CD80, CD86, CD54, and CD58 and a higher level of interleukin-12 than HspB-pulsed HMDCs. Moreover, Com1-pulsed HMDCs induced high-level proliferation and activation of CD4+ and CD8+ cells, which expressed high levels of T-cell activation marker CD69 and inflammatory cytokines IFN-γ and TNF-α. In contrast, HspB-pulsed HMDCs were unable to induce efficient T-cell proliferation and activation. Conclusions Our results demonstrate that Com1-pulsed HMDCs are able to induce efficient T-cell proliferation and drive T cells toward Th1 and Tc1 polarization; however, HspB-pulsed HMDCs are unable to do so. Unlike HspB, Com1 is a protective antigen, which was demonstrated by the adoptive transfer of Com1-pulsed bone marrow dendritic cells into naive BALB/c mice.

  9. Nitric oxide synthesis-promoting effects of valsartan in human umbilical vein endothelial cells via the Akt/adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway

    Directory of Open Access Journals (Sweden)

    Yingshuai Zhao

    2017-05-01

    Full Text Available Valsartan (VAL, an antagonist of angiotensin II receptor type 1, has antihypertensive and multiple cardiovascular protective effects. The pleiotropic functions of VAL are related to the increased synthesis and biological activity of intravascular nitric oxide (NO. In this study, the role and mechanisms of VAL in the synthesis of NO were examined in human umbilical vein endothelial cells (HUVECs. Ten µmol/L of VAL was used to treat EA.hy926 cells for 30 minutes, 1, 3, 6, 12, and 24 hours, and three concentrations of VAL (i.e., 10, 1, and 0.1 µmol/L were used to treat EA.hy926 cells for 24 hours. The cells were divided into five groups: control, VAL, VAL + Compound C (adenosine monophosphate-activated protein kinase [AMPK] inhibitor, 1 µmol/L, VAL + LY294002 (Akt [protein kinase B] inhibitor, 10 µmol/L, and VAL + L-nitro-arginine methyl ester (L-NAME, endothelial NO synthase [eNOS] inhibitor, 500 µmol/L groups. The NO content in the VAL-treated HUVEC line (EA.hy926 was detected using the nitrate reductase method, and western blot was used to detect the phosphorylation of Akt, AMPK, and eNOS, as well as the changes in total protein levels. VAL increased NO synthesis in EA.hy926 cells in time- and dose-dependent manners (p < 0.05 and the intracellular phosphorylation levels of Akt, AMPK, and eNOS at the corresponding time points. LY294002, Compound C, and L-NAME could inhibit the VAL-promoted NO synthesis. VAL activated Akt, AMPK, and eNOS, thus promoting NO synthesis and playing a protective role in endothelial cells. These results partially explained the mechanisms underlying the cardiovascular protective effects of VAL.

  10. Expression and Purification of Recombinant Human Basic Fibroblast Growth Factor Fusion Proteins and Their Uses in Human Stem Cell Culture.

    Science.gov (United States)

    Imsoonthornruksa, Sumeth; Pruksananonda, Kamthorn; Parnpai, Rangsun; Rungsiwiwut, Ruttachuk; Ketudat-Cairns, Mariena

    2015-01-01

    To reduce the cost of cytokines and growth factors in stem cell research, a simple method for the production of soluble and biological active human basic fibroblast growth factor (hbFGF) fusion protein in Escherichia coli was established. Under optimal conditions, approximately 60-80 mg of >95% pure hbFGF fusion proteins (Trx-6xHis-hbFGF and 6xHis-hbFGF) were obtained from 1 liter of culture broth. The purified hbFGF proteins, both with and without the fusion tags, were biologically active, which was confirmed by their ability to stimulate proliferation of NIH3T3 cells. The fusion proteins also have the ability to support several culture passages of undifferentiated human embryonic stem cells and induce pluripotent stem cells. This paper describes a low-cost and uncomplicated method for the production and purification of biologically active hbFGF fusion proteins. © 2015 S. Karger AG, Basel.

  11. Tribomechanical micronization and activation of whey protein ...

    Indian Academy of Sciences (India)

    Tribomechanics is a part of physics that is concerned with the study of phenomena that appear during milling under dynamic conditions. Tribomechanical micronization and activation (TMA) of whey protein concentrates (WPC) and zeolites (type clinoptilolite) were carried out. Samples of powdered WPC and zeolite were ...

  12. Solution structure and dynamics of melanoma inhibitory activity protein

    International Nuclear Information System (INIS)

    Lougheed, Julie C.; Domaille, Peter J.; Handel, Tracy M.

    2002-01-01

    Melanoma inhibitory activity (MIA) is a small secreted protein that is implicated in cartilage cell maintenance and melanoma metastasis. It is representative of a recently discovered family of proteins that contain a Src Homologous 3 (SH3) subdomain. While SH3 domains are normally found in intracellular proteins and mediate protein-protein interactions via recognition of polyproline helices, MIA is single-domain extracellular protein, and it probably binds to a different class of ligands.Here we report the assignments, solution structure, and dynamics of human MIA determined by heteronuclear NMR methods. The structures were calculated in a semi-automated manner without manual assignment of NOE crosspeaks, and have a backbone rmsd of 0.38 A over the ordered regions of the protein. The structure consists of an SH3-like subdomain with N- and C-terminal extensions of approximately 20 amino acids each that together form a novel fold. The rmsd between the solution structure and our recently reported crystal structure is 0.86 A over the ordered regions of the backbone, and the main differences are localized to the most dynamic regions of the protein. The similarity between the NMR and crystal structures supports the use of automated NOE assignments and ambiguous restraints to accelerate the calculation of NMR structures

  13. EML proteins in microtubule regulation and human disease.

    Science.gov (United States)

    Fry, Andrew M; O'Regan, Laura; Montgomery, Jessica; Adib, Rozita; Bayliss, Richard

    2016-10-15

    The EMLs are a conserved family of microtubule-associated proteins (MAPs). The founding member was discovered in sea urchins as a 77-kDa polypeptide that co-purified with microtubules. This protein, termed EMAP for echinoderm MAP, was the major non-tubulin component present in purified microtubule preparations made from unfertilized sea urchin eggs [J. Cell Sci. (1993) 104: , 445-450; J. Cell Sci. (1987) 87: (Pt 1), 71-84]. Orthologues of EMAP were subsequently identified in other echinoderms, such as starfish and sand dollar, and then in more distant eukaryotes, including flies, worms and vertebrates, where the name of ELP or EML (both for EMAP-like protein) has been adopted [BMC Dev. Biol. (2008) 8: , 110; Dev. Genes Evol. (2000) 210: , 2-10]. The common property of these proteins is their ability to decorate microtubules. However, whether they are associated with particular microtubule populations or exercise specific functions in different microtubule-dependent processes remains unknown. Furthermore, although there is limited evidence that they regulate microtubule dynamics, the biochemical mechanisms of their molecular activity have yet to be explored. Nevertheless, interest in these proteins has grown substantially because of the identification of EML mutations in neuronal disorders and oncogenic fusions in human cancers. Here, we summarize our current knowledge of the expression, localization and structure of what is proving to be an interesting and important class of MAPs. We also speculate about their function in microtubule regulation and highlight how the studies of EMLs in human diseases may open up novel avenues for patient therapy. © 2016 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  14. Rev and Rex proteins of human complex retroviruses function with the MMTV Rem-responsive element

    Directory of Open Access Journals (Sweden)

    Dudley Jaquelin P

    2009-02-01

    Full Text Available Abstract Background Mouse mammary tumor virus (MMTV encodes the Rem protein, an HIV Rev-like protein that enhances nuclear export of unspliced viral RNA in rodent cells. We have shown that Rem is expressed from a doubly spliced RNA, typical of complex retroviruses. Several recent reports indicate that MMTV can infect human cells, suggesting that MMTV might interact with human retroviruses, such as human immunodeficiency virus (HIV, human T-cell leukemia virus (HTLV, and human endogenous retrovirus type K (HERV-K. In this report, we test whether the export/regulatory proteins of human complex retroviruses will increase expression from vectors containing the Rem-responsive element (RmRE. Results MMTV Rem, HIV Rev, and HTLV Rex proteins, but not HERV-K Rec, enhanced expression from an MMTV-based reporter plasmid in human T cells, and this activity was dependent on the RmRE. No RmRE-dependent reporter gene expression was detectable using Rev, Rex, or Rec in HC11 mouse mammary cells. Cell fractionation and RNA quantitation experiments suggested that the regulatory proteins did not affect RNA stability or nuclear export in the MMTV reporter system. Rem had no demonstrable activity on export elements from HIV, HTLV, or HERV-K. Similar to the Rem-specific activity in rodent cells, the RmRE-dependent functions of Rem, Rev, or Rex in human cells were inhibited by a dominant-negative truncated nucleoporin that acts in the Crm1 pathway of RNA and protein export. Conclusion These data argue that many retroviral regulatory proteins recognize similar complex RNA structures, which may depend on the presence of cell-type specific proteins. Retroviral protein activity on the RmRE appears to affect a post-export function of the reporter RNA. Our results provide additional evidence that MMTV is a complex retrovirus with the potential for viral interactions in human cells.

  15. The human TRPV6 channel protein is associated with cyclophilin B in human placenta.

    Science.gov (United States)

    Stumpf, Tobias; Zhang, Qi; Hirnet, Daniela; Lewandrowski, Urs; Sickmann, Albert; Wissenbach, Ulrich; Dörr, Janka; Lohr, Christian; Deitmer, Joachim W; Fecher-Trost, Claudia

    2008-06-27

    Transcellular calcium transport in the kidney, pancreas, small intestine, and placenta is partly mediated by transient receptor potential (TRP) channels. The highly selective TRPV6 calcium channel protein is most likely important for the calcium transfer in different specialized epithelial cells. In the human placenta the protein is expressed in trophoblast tissue, where it is implicated in the transepithelial calcium transfer from mother to the fetus. We enriched the TRPV6 channel protein endogenously expressed in placenta together with annexin A2 and cyclophilin B (CypB), which is a member of the huge immunophilin family. In the human placenta TRPV6 and CypB are mainly located intracellularly in the syncytiotrophoblast layer, but a small amount of the mature glycosylated TRPV6 channel protein and CypB is also expressed in microvilli apical membranes, the fetomaternal barrier. To understand the role of CypB on the TRPV6 channel function, we evaluated the effect of CypB co-expression on TRPV6-mediated calcium uptake into Xenopus laevis oocytes expressing TRPV6. A significant increase of TRPV6-mediated calcium uptake was observed after CypB/TRPV6 co-expression. This stimulatory effect of CypB was reversed by the immunosuppressive drug cyclosporin A, which inhibits the enzymatic activity of CypB. Cyclosporin A had no significant effect on TRPV6 and CypB protein expression levels in the oocytes. In summary, our results establish CypB as a new TRPV6 accessory protein with potential involvement in TRPV6 channel activation through its peptidyl-prolyl cis/trans isomerase activity.

  16. Human and pneumococcal cell surface glyceraldehyde-3-phosphate dehydrogenase (GAPDH) proteins are both ligands of human C1q protein.

    Science.gov (United States)

    Terrasse, Rémi; Tacnet-Delorme, Pascale; Moriscot, Christine; Pérard, Julien; Schoehn, Guy; Vernet, Thierry; Thielens, Nicole M; Di Guilmi, Anne Marie; Frachet, Philippe

    2012-12-14

    C1q, a key component of the classical complement pathway, is a major player in the response to microbial infection and has been shown to detect noxious altered-self substances such as apoptotic cells. In this work, using complementary experimental approaches, we identified the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a C1q partner when exposed at the surface of human pathogenic bacteria Streptococcus pneumoniae and human apoptotic cells. The membrane-associated GAPDH on HeLa cells bound the globular regions of C1q as demonstrated by pulldown and cell surface co-localization experiments. Pneumococcal strains deficient in surface-exposed GAPDH harbored a decreased level of C1q recognition when compared with the wild-type strains. Both recombinant human and pneumococcal GAPDHs interacted avidly with C1q as measured by surface plasmon resonance experiments (K(D) = 0.34-2.17 nm). In addition, GAPDH-C1q complexes were observed by transmission electron microscopy after cross-linking. The purified pneumococcal GAPDH protein activated C1 in an in vitro assay unlike the human form. Deposition of C1q, C3b, and C4b from human serum at the surface of pneumococcal cells was dependent on the presence of surface-exposed GAPDH. This ability of C1q to sense both human and bacterial GAPDHs sheds new insights on the role of this important defense collagen molecule in modulating the immune response.

  17. Human and Pneumococcal Cell Surface Glyceraldehyde-3-phosphate Dehydrogenase (GAPDH) Proteins Are Both Ligands of Human C1q Protein*

    Science.gov (United States)

    Terrasse, Rémi; Tacnet-Delorme, Pascale; Moriscot, Christine; Pérard, Julien; Schoehn, Guy; Vernet, Thierry; Thielens, Nicole M.; Di Guilmi, Anne Marie; Frachet, Philippe

    2012-01-01

    C1q, a key component of the classical complement pathway, is a major player in the response to microbial infection and has been shown to detect noxious altered-self substances such as apoptotic cells. In this work, using complementary experimental approaches, we identified the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a C1q partner when exposed at the surface of human pathogenic bacteria Streptococcus pneumoniae and human apoptotic cells. The membrane-associated GAPDH on HeLa cells bound the globular regions of C1q as demonstrated by pulldown and cell surface co-localization experiments. Pneumococcal strains deficient in surface-exposed GAPDH harbored a decreased level of C1q recognition when compared with the wild-type strains. Both recombinant human and pneumococcal GAPDHs interacted avidly with C1q as measured by surface plasmon resonance experiments (KD = 0.34–2.17 nm). In addition, GAPDH-C1q complexes were observed by transmission electron microscopy after cross-linking. The purified pneumococcal GAPDH protein activated C1 in an in vitro assay unlike the human form. Deposition of C1q, C3b, and C4b from human serum at the surface of pneumococcal cells was dependent on the presence of surface-exposed GAPDH. This ability of C1q to sense both human and bacterial GAPDHs sheds new insights on the role of this important defense collagen molecule in modulating the immune response. PMID:23086952

  18. The human angiotensin AT(1) receptor supports G protein-independent extracellular signal-regulated kinase 1/2 activation and cellular proliferation

    DEFF Research Database (Denmark)

    Hansen, Jakob Lerche; Aplin, Mark; Hansen, Jonas Tind

    2008-01-01

    The angiotensin AT(1) receptor is a key regulator of blood pressure and body fluid homeostasis, and it plays a key role in the pathophysiology of several cardiovascular diseases such as hypertension, cardiac hypertrophy, congestive heart failure, and arrhythmia. The importance of human angiotensi...

  19. Differential activation of murine herpesvirus 68- and Kaposi's sarcoma-associated herpesvirus-encoded ORF74 G protein-coupled receptors by human and murine chemokines

    NARCIS (Netherlands)

    Verzijl, D.; Fitzsimons, C.P.; Van Dijk, M.; Stewart, J.P.; Timmerman, H.; Smit, M.J.; Leurs, R.

    2004-01-01

    Infection of mice with murine gammaherpesvirus 68 (MHV-68) is a well-characterized small animal model for the study of gammaherpesvirus infection. MHV-68 belongs to the same herpesvirus family as herpesvirus saimiri (HVS) of New World squirrel monkeys and human herpesvirus 8 (HHV-8) (also referred

  20. Small heat shock proteins potentiate amyloid dissolution by protein disaggregases from yeast and humans.

    Directory of Open Access Journals (Sweden)

    Martin L Duennwald

    Full Text Available How small heat shock proteins (sHsps might empower proteostasis networks to control beneficial prions or disassemble pathological amyloid is unknown. Here, we establish that yeast sHsps, Hsp26 and Hsp42, inhibit prionogenesis by the [PSI+] prion protein, Sup35, via distinct and synergistic mechanisms. Hsp42 prevents conformational rearrangements within molten oligomers that enable de novo prionogenesis and collaborates with Hsp70 to attenuate self-templating. By contrast, Hsp26 inhibits self-templating upon binding assembled prions. sHsp binding destabilizes Sup35 prions and promotes their disaggregation by Hsp104, Hsp70, and Hsp40. In yeast, Hsp26 or Hsp42 overexpression prevents [PSI+] induction, cures [PSI+], and potentiates [PSI+]-curing by Hsp104 overexpression. In vitro, sHsps enhance Hsp104-catalyzed disaggregation of pathological amyloid forms of α-synuclein and polyglutamine. Unexpectedly, in the absence of Hsp104, sHsps promote an unprecedented, gradual depolymerization of Sup35 prions by Hsp110, Hsp70, and Hsp40. This unanticipated amyloid-depolymerase activity is conserved from yeast to humans, which lack Hsp104 orthologues. A human sHsp, HspB5, stimulates depolymerization of α-synuclein amyloid by human Hsp110, Hsp70, and Hsp40. Thus, we elucidate a heretofore-unrecognized human amyloid-depolymerase system that could have applications in various neurodegenerative disorders.

  1. Antiproliferative activity of recombinant human interferon-λ2 ...

    African Journals Online (AJOL)

    Antiproliferative activity of recombinant human interferon-λ2 expressed in stably ... The representing 26 kDa protein band of IFN-λ2 was detected by SDS-PAGE and ... The antiproliferative activity of hIFN-λ2 was determined by MTT assay.

  2. Structural History of Human SRGAP2 Proteins.

    Science.gov (United States)

    Sporny, Michael; Guez-Haddad, Julia; Kreusch, Annett; Shakartzi, Sivan; Neznansky, Avi; Cross, Alice; Isupov, Michail N; Qualmann, Britta; Kessels, Michael M; Opatowsky, Yarden

    2017-06-01

    In the development of the human brain, human-specific genes are considered to play key roles, conferring its unique advantages and vulnerabilities. At the time of Homo lineage divergence from Australopithecus, SRGAP2C gradually emerged through a process of serial duplications and mutagenesis from ancestral SRGAP2A (3.4-2.4 Ma). Remarkably, ectopic expression of SRGAP2C endows cultured mouse brain cells, with human-like characteristics, specifically, increased dendritic spine length and density. To understand the molecular mechanisms underlying this change in neuronal morphology, we determined the structure of SRGAP2A and studied the interplay between SRGAP2A and SRGAP2C. We found that: 1) SRGAP2A homo-dimerizes through a large interface that includes an F-BAR domain, a newly identified F-BAR extension (Fx), and RhoGAP-SH3 domains. 2) SRGAP2A has an unusual inverse geometry, enabling associations with lamellipodia and dendritic spine heads in vivo, and scaffolding of membrane protrusions in cell culture. 3) As a result of the initial partial duplication event (∼3.4 Ma), SRGAP2C carries a defective Fx-domain that severely compromises its solubility and membrane-scaffolding ability. Consistently, SRGAP2A:SRAGP2C hetero-dimers form, but are insoluble, inhibiting SRGAP2A activity. 4) Inactivation of SRGAP2A is sensitive to the level of hetero-dimerization with SRGAP2C. 5) The primal form of SRGAP2C (P-SRGAP2C, existing between ∼3.4 and 2.4 Ma) is less effective in hetero-dimerizing with SRGAP2A than the modern SRGAP2C, which carries several substitutions (from ∼2.4 Ma). Thus, the genetic mutagenesis phase contributed to modulation of SRGAP2A's inhibition of neuronal expansion, by introducing and improving the formation of inactive SRGAP2A:SRGAP2C hetero-dimers, indicating a stepwise involvement of SRGAP2C in human evolutionary history. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  3. Salsalate ameliorates metabolic disturbances by reducing inflammation in spontaneously hypertensive rats expressing human C-reactive protein and by activating brown adipose tissue in nontransgenic controls

    Czech Academy of Sciences Publication Activity Database

    Trnovská, J.; Šilhavý, Jan; Kuda, Ondřej; Landa, Vladimír; Zídek, Václav; Mlejnek, Petr; Šimáková, Miroslava; Strnad, Hynek; Škop, V.; Oliyarnyk, O.; Kazdová, L.; Haluzík, M.; Pravenec, Michal

    2017-01-01

    Roč. 12, č. 6 (2017), č. článku e0179063. E-ISSN 1932-6203 R&D Projects: GA ČR(CZ) GA13-04420S Institutional support: RVO:67985823 ; RVO:68378050 Keywords : inflammation * insulin resistance * C-reactive protein * spintaneously hypertensive rat * salsalate Subject RIV: EB - Genetics ; Molecular Biology; EB - Genetics ; Molecular Biology (UMG-J) OBOR OECD: Endocrinology and metabolism (including diabetes, hormones); Endocrinology and metabolism (including diabetes, hormones) (UMG-J) Impact factor: 2.806, year: 2016

  4. A human protein interaction network shows conservation of aging processes between human and invertebrate species.

    Directory of Open Access Journals (Sweden)

    Russell Bell

    2009-03-01

    Full Text Available We have mapped a protein interaction network of human homologs of proteins that modify longevity in invertebrate species. This network is derived from a proteome-scale human protein interaction Core Network generated through unbiased high-throughput yeast two-hybrid searches. The longevity network is composed of 175 human homologs of proteins known to confer increased longevity through loss of function in yeast, nematode, or fly, and 2,163 additional human proteins that interact with these homologs. Overall, the network consists of 3,271 binary interactions among 2,338 unique proteins. A comparison of the average node degree of the human longevity homologs with random sets of proteins in the Core Network indicates that human homologs of longevity proteins are highly connected hubs with a mean node degree of 18.8 partners. Shortest path length analysis shows that proteins in this network are significantly more connected than would be expected by chance. To examine the relationship of this network to human aging phenotypes, we compared the genes encoding longevity network proteins to genes known to be changed transcriptionally during aging in human muscle. In the case of both the longevity protein homologs and their interactors, we observed enrichments for differentially expressed genes in the network. To determine whether homologs of human longevity interacting proteins can modulate life span in invertebrates, homologs of 18 human FRAP1 interacting proteins showing significant changes in human aging muscle were tested for effects on nematode life span using RNAi. Of 18 genes tested, 33% extended life span when knocked-down in Caenorhabditis elegans. These observations indicate that a broad class of longevity genes identified in invertebrate models of aging have relevance to human aging. They also indicate that the longevity protein interaction network presented here is enriched for novel conserved longevity proteins.

  5. Informing the Human Plasma Protein Binding of ...

    Science.gov (United States)

    The free fraction of a xenobiotic in plasma (Fub) is an important determinant of chemical adsorption, distribution, metabolism, elimination, and toxicity, yet experimental plasma protein binding data is scarce for environmentally relevant chemicals. The presented work explores the merit of utilizing available pharmaceutical data to predict Fub for environmentally relevant chemicals via machine learning techniques. Quantitative structure-activity relationship (QSAR) models were constructed with k nearest neighbors (kNN), support vector machines (SVM), and random forest (RF) machine learning algorithms from a training set of 1045 pharmaceuticals. The models were then evaluated with independent test sets of pharmaceuticals (200 compounds) and environmentally relevant ToxCast chemicals (406 total, in two groups of 238 and 168 compounds). The selection of a minimal feature set of 10-15 2D molecular descriptors allowed for both informative feature interpretation and practical applicability domain assessment via a bounded box of descriptor ranges and principal component analysis. The diverse pharmaceutical and environmental chemical sets exhibit similarities in terms of chemical space (99-82% overlap), as well as comparable bias and variance in constructed learning curves. All the models exhibit significant predictability with mean absolute errors (MAE) in the range of 0.10-0.18 Fub. The models performed best for highly bound chemicals (MAE 0.07-0.12), neutrals (MAE 0

  6. Raman optical activity of proteins and glycoproteins

    International Nuclear Information System (INIS)

    Smyth, E.

    2000-03-01

    Raman optical activity (ROA), measured in this project as a small difference in the intensity of Raman scattering from chiral molecules in right- and left-circularly polarised incident laser light, offers the potential to provide more information about the structure of biological molecules in aqueous solution than conventional spectroscopic techniques. Chapter one contains a general discussion of the relative merits of different spectroscopic techniques for structure determination of biomolecules, as well as a brief introduction to ROA. In Chapter two a theoretical analysis of ROA is developed, which extends the discussion in chapter one. The spectrometer setup and sample preparation is then discussed in chapter three. Instrument and sample conditions are monitored to ensure that the best results are obtained. As with any experimental project problems occur, which may result in a degradation of the spectra obtained. The cause of these problems was explored and remedied whenever possible. Chapter four introduces a brief account of protein, glycoprotein and carbohydrate structure and function, with a particular emphasis on the structure of proteins. In the remaining chapters experimental ROA results on proteins and glycoproteins, with some carbohydrate samples, from a wide range of sources are examined. For example, in chapter five some β-sheet proteins are examined. Structural features in these proteins are examined in the extended amide III region of their ROA spectra, revealing that ROA is sensitive to the rigidity or flexibility inherent in proteins. Chapter six concentrates on a group of proteins (usually glycoproteins) known as the serine proteinase inhibitors (serpins). Medically, the serpins are one of the most important groups of proteins of current interest, with wide-ranging implications in conditions such as Down's syndrome, Alzheimer's disease, and emphysema with associated cirrhosis of the liver. With favourable samples and conditions ROA may offer the

  7. The human CFTR protein expressed in CHO cells activates aquaporin-3 in a cAMP-dependent pathway: study by digital holographic microscopy

    KAUST Repository

    Jourdain, P.; Becq, F.; Lengacher, S.; Boinot, C.; Magistretti, Pierre J.; Marquet, P.

    2013-01-01

    The transmembrane water movements during cellular processes and their relationship to ionic channel activity remain largely unknown. As an example, in epithelial cells it was proposed that the movement of water could be directly linked to cystic

  8. Reassessing the Potential Activities of Plant CGI-58 Protein.

    Directory of Open Access Journals (Sweden)

    Abdallah Khatib

    Full Text Available Comparative Gene Identification-58 (CGI-58 is a widespread protein found in animals and plants. This protein has been shown to participate in lipolysis in mice and humans by activating Adipose triglyceride lipase (ATGL, the initial enzyme responsible for the triacylglycerol (TAG catabolism cascade. Human mutation of CGI-58 is the cause of Chanarin-Dorfman syndrome, an orphan disease characterized by a systemic accumulation of TAG which engenders tissue disorders. The CGI-58 protein has also been shown to participate in neutral lipid metabolism in plants and, in this case, a mutation again provokes TAG accumulation. Although its roles as an ATGL coactivator and in lipid metabolism are quite clear, the catalytic activity of CGI-58 is still in question. The acyltransferase activities of CGI-58 have been speculated about, reported or even dismissed and experimental evidence that CGI-58 expressed in E. coli possesses an unambiguous catalytic activity is still lacking. To address this problem, we developed a new set of plasmids and site-directed mutants to elucidate the in vivo effects of CGI-58 expression on lipid metabolism in E. coli. By analyzing the lipid composition in selected E. coli strains expressing CGI-58 proteins, and by reinvestigating enzymatic tests with adequate controls, we show here that recombinant plant CGI-58 has none of the proposed activities previously described. Recombinant plant and mouse CGI-58 both lack acyltransferase activity towards either lysophosphatidylglycerol or lysophosphatidic acid to form phosphatidylglycerol or phosphatidic acid and recombinant plant CGI-58 does not catalyze TAG or phospholipid hydrolysis. However, expression of recombinant plant CGI-58, but not mouse CGI-58, led to a decrease in phosphatidylglycerol in all strains of E. coli tested, and a mutation of the putative catalytic residues restored a wild-type phenotype. The potential activities of plant CGI-58 are subsequently discussed.

  9. Reassessing the Potential Activities of Plant CGI-58 Protein

    Science.gov (United States)

    Khatib, Abdallah; Arhab, Yani; Bentebibel, Assia; Abousalham, Abdelkarim; Noiriel, Alexandre

    2016-01-01

    Comparative Gene Identification-58 (CGI-58) is a widespread protein found in animals and plants. This protein has been shown to participate in lipolysis in mice and humans by activating Adipose triglyceride lipase (ATGL), the initial enzyme responsible for the triacylglycerol (TAG) catabolism cascade. Human mutation of CGI-58 is the cause of Chanarin-Dorfman syndrome, an orphan disease characterized by a systemic accumulation of TAG which engenders tissue disorders. The CGI-58 protein has also been shown to participate in neutral lipid metabolism in plants and, in this case, a mutation again provokes TAG accumulation. Although its roles as an ATGL coactivator and in lipid metabolism are quite clear, the catalytic activity of CGI-58 is still in question. The acyltransferase activities of CGI-58 have been speculated about, reported or even dismissed and experimental evidence that CGI-58 expressed in E. coli possesses an unambiguous catalytic activity is still lacking. To address this problem, we developed a new set of plasmids and site-directed mutants to elucidate the in vivo effects of CGI-58 expression on lipid metabolism in E. coli. By analyzing the lipid composition in selected E. coli strains expressing CGI-58 proteins, and by reinvestigating enzymatic tests with adequate controls, we show here that recombinant plant CGI-58 has none of the proposed activities previously described. Recombinant plant and mouse CGI-58 both lack acyltransferase activity towards either lysophosphatidylglycerol or lysophosphatidic acid to form phosphatidylglycerol or phosphatidic acid and recombinant plant CGI-58 does not catalyze TAG or phospholipid hydrolysis. However, expression of recombinant plant CGI-58, but not mouse CGI-58, led to a decrease in phosphatidylglycerol in all strains of E. coli tested, and a mutation of the putative catalytic residues restored a wild-type phenotype. The potential activities of plant CGI-58 are subsequently discussed. PMID:26745266

  10. De Novo Construction of Redox Active Proteins.

    Science.gov (United States)

    Moser, C C; Sheehan, M M; Ennist, N M; Kodali, G; Bialas, C; Englander, M T; Discher, B M; Dutton, P L

    2016-01-01

    Relatively simple principles can be used to plan and construct de novo proteins that bind redox cofactors and participate in a range of electron-transfer reactions analogous to those seen in natural oxidoreductase proteins. These designed redox proteins are called maquettes. Hydrophobic/hydrophilic binary patterning of heptad repeats of amino acids linked together in a single-chain self-assemble into 4-alpha-helix bundles. These bundles form a robust and adaptable frame for uncovering the default properties of protein embedded cofactors independent of the complexities introduced by generations of natural selection and allow us to better understand what factors can be exploited by man or nature to manipulate the physical chemical properties of these cofactors. Anchoring of redox cofactors such as hemes, light active tetrapyrroles, FeS clusters, and flavins by His and Cys residues allow cofactors to be placed at positions in which electron-tunneling rates between cofactors within or between proteins can be predicted in advance. The modularity of heptad repeat designs facilitates the construction of electron-transfer chains and novel combinations of redox cofactors and new redox cofactor assisted functions. Developing de novo designs that can support cofactor incorporation upon expression in a cell is needed to support a synthetic biology advance that integrates with natural bioenergetic pathways. © 2016 Elsevier Inc. All rights reserved.

  11. Protein kinase CK2 in human diseases

    DEFF Research Database (Denmark)

    Guerra, Barbara; Issinger, Olaf-Georg

    2008-01-01

    Protein kinase CK2 (formerly referred to as casein kinase II) is an evolutionary conserved, ubiquitous protein kinase. There are two paralog catalytic subunits, i.e. alpha (A1) and alpha' (A2). The alpha and alpha' subunits are linked to two beta subunits to produce a heterotetrameric structure...

  12. Deoxyribonucleic-binding homeobox proteins are augmented in human cancer

    DEFF Research Database (Denmark)

    Wewer, U M; Mercurio, A M; Chung, S Y

    1990-01-01

    Homeobox genes encode sequence-specific DNA-binding proteins that are involved in the regulation of gene expression during embryonic development. In this study, we examined the expression of homeobox proteins in human cancer. Antiserum was obtained against a synthetic peptide derived from...... was then isolated and used to elicit a rabbit antiserum. In immunostaining, both antisera reacted with the nuclei of cultured tumor cells. In tissue sections of human carcinoma, nuclear immunoreactivity was observed in the tumor cells in 40 of 42 cases examined. Adjacent normal epithelial tissue obtained from......, the presence of the homeobox transcript in human carcinoma was documented by in situ hybridization and RNase protection mapping. These results demonstrate that human cancer is associated with the expression of homeobox proteins. Such homeobox proteins, as well as other regulatory proteins, could be involved...

  13. Degradation of tissue-type plasminogen activator by human monocyte- derived macrophages is mediated by the mannose receptor and by the low- density lipoprotein receptor-related protein

    NARCIS (Netherlands)

    Noorman, F.; Braat, E.A.M.; Rijken, D.C.

    1995-01-01

    The balance of tissue-type plasminogen activator (t-PA) production and degradation determines its concentration in blood and tissues. Disturbance of this balance may result in either increased or decreased proteolysis. In the present study, we identified the receptor systems involved in the

  14. Human mesenchymal stem cell proliferation is regulated by PGE2 through differential activation of cAMP-dependent protein kinase isoforms

    DEFF Research Database (Denmark)

    Kleiveland, Charlotte Ramstad; Kassem, Moustapha; Lea, Tor

    2008-01-01

    The conditions used for in vitro differentiation of hMSCs contain substances that affect the activity and expression of cyclooxygenase enzymes (COX1/COX2) and thereby the synthesis of prostanoids. hMSC constitutively produce PGE2 when cultivated in vitro. In this study we have investigated effect...

  15. Human Cells as Platform to Produce Gamma-Carboxylated Proteins.

    Science.gov (United States)

    de Sousa Bomfim, Aline; de Freitas, Marcela Cristina Corrêa; Covas, Dimas Tadeu; de Sousa Russo, Elisa Maria

    2018-01-01

    The gamma-carboxylated proteins belong to a family of proteins that depend on vitamin K for normal biosynthesis. The major representative gamma-carboxylated proteins are the coagulation system proteins, for example, factor VII, factor IX, factor X, prothrombin, and proteins C, S, and Z. These molecules have harbored posttranslational modifications, such as glycosylation and gamma-carboxylation, and for this reason they need to be produced in mammalian cell lines. Human cells lines have emerged as the most promising alternative to the production of gamma-carboxylated proteins. In this chapter, the methods to generate human cells as a platform to produce gamma-carboxylated proteins, for example the coagulation factors VII and IX, are presented. From the cell line modification up to the vitamin K adaptation of the produced cells is described in the protocols presented in this chapter.

  16. Human mesenchymal stem cell proliferation is regulated by PGE2 through differential activation of cAMP-dependent protein kinase isoforms

    International Nuclear Information System (INIS)

    Kleiveland, Charlotte Ramstad; Kassem, Moustapha; Lea, Tor

    2008-01-01

    The conditions used for in vitro differentiation of hMSCs contain substances that affect the activity and expression of cyclooxygenase enzymes (COX1/COX2) and thereby the synthesis of prostanoids. hMSC constitutively produce PGE2 when cultivated in vitro. In this study we have investigated effects of PGE2 on proliferation of hMSC. We here demonstrate that one of the main control molecules in the Wnt pathway, GSK-3β, is phosphorylated at the negative regulatory site ser-9 after treating the cells with PGE2. This phosphorylation is mediated by elevation of cAMP and subsequent activation of PKA. Furthermore, PGE2 treatment leads to enhanced nuclear translocation of β-catenin, thus influencing cell proliferation. The presence of two PKA isoforms, types I and II, prompted us to investigate their individual contribution in PGE2-mediated regulation of proliferation. Specific activation of PKA type II with synthetic cAMP analogues, resulted in enhancement of proliferation. On the other side, we found that treatment of hMSC with high concentrations of PGE2 inhibited cell proliferation by arresting the cells in G 0 /G 1 phase, an effect we found to be mediated by PKA I. Hence, the two different PKA isoforms seem to have opposing functions in the regulation of proliferation and differentiation in these cells

  17. Lipoxin A4 regulates expression of the estrogen receptor and inhibits 17β-estradiol induced p38 mitogen-activated protein kinase phosphorylation in human endometriotic stromal cells.

    Science.gov (United States)

    Chen, Shuo; Wu, Rong-Feng; Su, Lin; Zhou, Wei-Dong; Zhu, Mao-Bi; Chen, Qiong-Hua

    2014-07-01

    To study the role of lipoxin A4 (LXA4) in endometriosis. Molecular analysis in human samples and primary human endometriotic stromal cells (ESCs). University hospital. Forty-nine premenopausal women (30 patients with endometriosis and 19 controls). Normal and ectopic endometrial biopsies obtained during surgery performed during the proliferative phase of the menstrual cycle; ESCs used for in vitro studies. Levels of LXA4 measured by enzyme-linked immunosorbent assay (ELISA); mRNA levels of the estrogen receptor (ER), progestogen receptor (PR), tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) quantified by quantitative reverse-transcription polymerase chain reaction (qRT-PCR); and p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation evaluated by Western blotting. The LXA4 expression level decreased in ectopic tissue as well as ERα and PR, although the expression of ERβ increased in ectopic endometrium compared with the controls. Investigations with correlation analysis revealed the expression of LXA4 was positively correlated with ERα and negatively correlated with ERβ in vivo. Moreover, administering LXA4 could augment ERβ expression in ESCs and inhibit the 17β-estradiol-induced phosphorylation of p38 MAPK very likely through ERβ. Our findings indicate that LXA4 regulates ERβ expression and inhibits 17β-estradiol-induced phosphorylation of p38 MAPK, very likely through ERβ in ESCs. Copyright © 2014. Published by Elsevier Inc.

  18. Gc protein-derived macrophage-activating factor (GcMAF) stimulates cAMP formation in human mononuclear cells and inhibits angiogenesis in chick embryo chorionallantoic membrane assay.

    Science.gov (United States)

    Pacini, Stefania; Morucci, Gabriele; Punzi, Tiziana; Gulisano, Massimo; Ruggiero, Marco

    2011-04-01

    The effects of Gc protein-derived macrophage-activating factor (GcMAF) have been studied in cancer and other conditions where angiogenesis is deregulated. In this study, we demonstrate for the first time that the mitogenic response of human peripheral blood mononuclear cells (PBMCs) to GcMAF was associated with 3'-5'-cyclic adenosine monophosphate (cAMP) formation. The effect was dose dependent, and maximal stimulation was achieved using 0.1 ng/ml. Heparin inhibited the stimulatory effect of GcMAF on PBMCs. In addition, we demonstrate that GcMAF (1 ng/ml) inhibited prostaglandin E(1)- and human breast cancer cell-stimulated angiogenesis in chick embryo chorionallantoic membrane (CAM) assay. Finally, we tested different GcMAF preparations on CAM, and the assay proved to be a reliable, reproducible and inexpensive method to determine the relative potencies of different preparations and their stability; we observed that storage at room temperature for 15 days decreased GcMAF potency by about 50%. These data could prove useful for upcoming clinical trials on GcMAF.

  19. Radioimmunoassay of human eosinophil cationic protein

    International Nuclear Information System (INIS)

    Venge, P.; Roxin, L.E.; Olsson, I.

    1977-01-01

    A radioimmunosorbent assay has been developed which allows the detection in serum of a cationic protein derived from eosinophil granulocytes. In 34 healthy individuals the mean level was 31 μg/l. with a range of 5 to 55 μg/l. The serum concentration of 'eosinophil' cationic protein was correlated (P<0.001) to the number of eosinophil granulocytes in peripheral blood. Quantitiation of 'eosinophil' cationic protein in serum might be useful in the study of eosinophil granulocyte turnover and function in vivo. (author)

  20. An experimental and computational framework to build a dynamic protein atlas of human cell division

    OpenAIRE

    Kavur, Marina; Kavur, Marina; Kavur, Marina; Ellenberg, Jan; Peters, Jan-Michael; Ladurner, Rene; Martinic, Marina; Kueblbeck, Moritz; Nijmeijer, Bianca; Wachsmuth, Malte; Koch, Birgit; Walther, Nike; Politi, Antonio; Heriche, Jean-Karim; Hossain, M.

    2017-01-01

    Essential biological functions of human cells, such as division, require the tight coordination of the activity of hundreds of proteins in space and time. While live cell imaging is a powerful tool to study the distribution and dynamics of individual proteins after fluorescence tagging, it has not yet been used to map protein networks due to the lack of systematic and quantitative experimental and computational approaches. Using the cell and nuclear boundaries as landmarks, we generated a 4D ...

  1. Reshaping Human Antibodies: Grafting an Antilysozyme Activity

    Science.gov (United States)

    Verhoeyen, Martine; Milstein, Cesar; Winter, Greg

    1988-03-01

    The production of therapeutic human monoclonal antibodies by hybridoma technology has proved difficult, and this has prompted the ``humanizing'' of mouse monoclonal antibodies by recombinant DNA techniques. It was shown previously that the binding site for a small hapten could be grafted from the heavy-chain variable domain of a mouse antibody to that of a human myeloma protein by transplanting the hypervariable loops. It is now shown that a large binding site for a protein antigen (lysozyme) can also be transplanted from mouse to human heavy chain. The success of such constructions may be facilitated by an induced-fit mechanism.

  2. Protein oxidation and degradation during proliferative senescence of human MRC-5 fibroblasts.

    Science.gov (United States)

    Sitte, N; Merker, K; von Zglinicki, T; Grune, T

    2000-03-01

    One of the highlights of age-related changes of cellular metabolism is the accumulation of oxidized proteins. The aging process on a cellular level can be treated either as the ongoing proliferation until a certain number of cell divisions is reached (the Hayflick limit) or as the aging of nondividing cells, that is, the age-related changes in cells without proliferation. The present investigation was undertaken to reveal the changes in protein turnover, proteasome activity, and protein oxidation status during proliferative senescence. We were able to demonstrate that the activity of the cytosolic proteasomal system declines dramatically during the proliferative senescence of human MRC-5 fibroblasts. Regardless of the loss in activity, it could be demonstrated that there are no changes in the transcription and translation of proteasomal subunits. This decline in proteasome activity was accompanied by an increased concentration of oxidized proteins. Cells at higher proliferation stages were no longer able to respond with increased degradation of endogenous [(35)S]-Met-radiolabeled proteins after hydrogen peroxide- or quinone-induced oxidative stress. It could be demonstrated that oxidized proteins in senescent human MRC-5 fibroblasts are not as quickly removed as they are in young cells. Therefore, our study demonstrates that the accumulation of oxidized proteins and decline in protein turnover and activity of the proteasomal system are not only a process of postmitotic aging but also occur during proliferative senescence and result in an increased half-life of oxidized proteins.

  3. Functional similarities between the dictyostelium protein AprA and the human protein dipeptidyl-peptidase IV.

    Science.gov (United States)

    Herlihy, Sarah E; Tang, Yu; Phillips, Jonathan E; Gomer, Richard H

    2017-03-01

    Autocrine proliferation repressor protein A (AprA) is a protein secreted by Dictyostelium discoideum cells. Although there is very little sequence similarity between AprA and any human protein, AprA has a predicted structural similarity to the human protein dipeptidyl peptidase IV (DPPIV). AprA is a chemorepellent for Dictyostelium cells, and DPPIV is a chemorepellent for neutrophils. This led us to investigate if AprA and DPPIV have additional functional similarities. We find that like AprA, DPPIV is a chemorepellent for, and inhibits the proliferation of, D. discoideum cells, and that AprA binds some DPPIV binding partners such as fibronectin. Conversely, rAprA has DPPIV-like protease activity. These results indicate a functional similarity between two eukaryotic chemorepellent proteins with very little sequence similarity, and emphasize the usefulness of using a predicted protein structure to search a protein structure database, in addition to searching for proteins with similar sequences. © 2016 The Protein Society.

  4. Production of C-reactive protein by human lymphocytes

    International Nuclear Information System (INIS)

    Kuta, A.E.; Baum, L.L.

    1986-01-01

    C-reactive protein (CRP) is a major acute phase serum protein in humans; it is detectable at very high concentrations during infection and tissue trauma. This protein is a pentame composed of five identical, 21,500 MW subunits. CRP is detectable on the surface of approximately 4% of normal peripheral blood lymphocytes (PBL). CRP binds its physiological ligands in a Ca ++ dependent manner; removal of Ca ++ does not alter the expression of CRP on the lymphocyte surface. Recently, investigators in this laboratory reported substantial inhibition of natural killer cell (NK) activity with anti-CRP antibodies. The following studies were undertaken to determine the origin of surface-CRP (S-CRP) found on normal PBL. Cells were incubated in methionine-free DMEM supplemented with 35 S-methionine. Cells were lysed and subjected to immunoprecipitation with anti-CRP and Staphylococcus aureus; immunoprecipitates were analyzed by SDS-PAGE and autoradiography. Data presented here suggested that lymphocytes, in particular, LGL produce small amounts of CRP and express it on their surface. Lymphocytes do not appear to secrete CRP since no CRP could be detected in culture supernatants. In addition, preliminary evidence indicates that peripheral blood monocytes produce no detectable CRP. Present studies utilizing Northern blot analysis are underway in order to detect CRP-mRNA

  5. Expression of Human CTP Synthetase in Saccharomyces cerevisiae Reveals Phosphorylation by Protein Kinase A*

    Science.gov (United States)

    Han, Gil-Soo; Sreenivas, Avula; Choi, Mal-Gi; Chang, Yu-Fang; Martin, Shelley S.; Baldwin, Enoch P.; Carman, George M.

    2005-01-01

    CTP synthetase (EC 6.3.4.2, UTP: ammonia ligase (ADP-forming)) is an essential enzyme in all organisms; it generates the CTP required for the synthesis of nucleic acids and membrane phospholipids. In this work we showed that the human CTP synthetase genes, CTPS1 and CTPS2, were functional in Saccharomyces cerevisiae and complemented the lethal phenotype of the ura7Δ ura8Δ mutant lacking CTP synthetase activity. The expression of the CTPS1-and CTPS2-encoded human CTP synthetase enzymes in the ura7Δ ura8Δ mutant was shown by immunoblot analysis of CTP synthetase proteins, the measurement of CTP synthetase activity, and the synthesis of CTP in vivo. Phosphoamino acid and phosphopeptide mapping analyses of human CTP synthetase 1 isolated from 32Pi-labeled cells revealed that the enzyme was phosphorylated on multiple serine residues in vivo. Activation of protein kinase A activity in yeast resulted in transient increases (2-fold) in the phosphorylation of human CTP synthetase 1 and the cellular level of CTP. Human CTP synthetase 1 was also phosphorylated by mammalian protein kinase A in vitro. Using human CTP synthetase 1 purified from Escherichia coli as a substrate, protein kinase A activity was dose- and time-dependent, and dependent on the concentrations of CTP synthetase1 and ATP. These studies showed that S. cerevisiae was useful for the analysis of human CTP synthetase phosphorylation. PMID:16179339

  6. A catalogue of human secreted proteins and its implications

    Directory of Open Access Journals (Sweden)

    Shivakumar Keerthikumar

    2016-11-01

    Full Text Available Under both normal and pathological conditions, cells secrete variety of proteins through classical and non-classical secretory pathways into the extracellular space. Majority of these proteins represent pathophysiology of the cell from which it is secreted. Recently, though more than 92% of the protein coding genes has been mapped by human proteome map project, but number of those proteins that constitutes secretome of the cell still remains elusive. Secreted proteins or the secretome can be accessible in bodily fluids and hence are considered as potential biomarkers to discriminate between healthy and diseased individuals. In order to facilitate the biomarker discovery and to further aid clinicians and scientists working in these arenas, we have compiled and catalogued secreted proteins from the human proteome using integrated bioinformatics approach. In this study, nearly 14% of the human proteome is likely to be secreted through classical and non-classical secretory pathways. Out of which, ~38% of these secreted proteins were found in extracellular vesicles including exosomes and shedding microvesicles. Among these secreted proteins, 94% were detected in human bodily fluids including blood, plasma, serum, saliva, semen, tear and urine. We anticipate that this high confidence list of secreted proteins could serve as a compendium of candidate biomarkers. In addition, the catalogue may provide functional insights in understanding the molecular mechanisms involved in various physiological and pathophysiological conditions of the cell.

  7. Characterization of the allosteric binding pocket of human liver fructose-1,6-bisphosphatase by protein crystallography and inhibitor activity studies.

    Science.gov (United States)

    Iversen, L F; Brzozowski, M; Hastrup, S; Hubbard, R; Kastrup, J S; Larsen, I K; Naerum, L; Nørskov-Lauridsen, L; Rasmussen, P B; Thim, L; Wiberg, F C; Lundgren, K

    1997-05-01

    The structures of three complexes of human fructose-1,6-bisphosphatase (FB) with the allosteric inhibitor AMP and two AMP analogues have been determined and all fully refined. The data used for structure determination were collected at cryogenic temperature (110 K), and with the use of synchrotron radiation. The structures reveal a common mode of binding for AMP and formycine monophosphate (FMP). 5-Amino-4-carboxamido-1 beta-D-5-phosphate-ribofuranosyl-1H-imidazole (AICAR-P) shows an unexpected mode of binding to FB, different from that of the other two ligands. The imidazole ring of AICAR-P is rotated 180 degrees compared to the AMP and FMP bases. This rotation results in a slightly different hydrogen bonding pattern and minor changes in the water structure in the binding pocket. Common features of binding are seen for the ribose and phosphate moieties of all three compounds. Although binding in a different mode, AICAR-P is still capable of making all the important interactions with the residues building the allosteric binding pocket. The IC50 values of AMP, FMP, and AICAR-P were determined to be 1.7, 1.4, and 20.9 microM, respectively. Thus, the approximately 10 times lower potency of AICAR-P is difficult to explain solely from the variations observed in the binding pocket. Only one water molecule in the allosteric binding pocket was found to be conserved in all four subunits in all three structures. This water molecule coordinates to a phosphate oxygen atom and the N7 atom of the AMP molecule, and to similarly situated atoms in the FMP and AICAR-P complexes. This implies an important role of the conserved water molecule in binding of the ligand.

  8. Human activities threaten coral reefs

    International Nuclear Information System (INIS)

    Tveitdal, Svein; Bjoerke, Aake

    2002-01-01

    Research indicates that 58 per cent of the coral reefs of the world are threatened by human activities. Pollution and global heating represent some of the threats. Coral reefs just beneath the surface of the sea are very sensitive to temperature changes. Since 1979, mass death of coral reefs has been reported increasingly often. More than 1000 marine species live in the coral reefs, among these are one fourth of all marine species of fish. It is imperative that the coral reefs be preserved, as coastal communities all over the world depend on them as sources of food and as they are the raw materials for important medicines. The article discusses the threats to the coral reefs in general and does not single out any particular energy-related activity as the principal threat. For instance, the El-Nino phenomenon of the Pacific Ocean is probably involved in mass death of coral reefs and in the North Sea large parts of deep-water reefs have been crushed by heavy beam trawlers fishing for bottom fish

  9. The Staphyloccous aureus Eap protein activates expression of proinflammatory cytokines.

    Science.gov (United States)

    Scriba, Thomas J; Sierro, Sophie; Brown, Eric L; Phillips, Rodney E; Sewell, Andrew K; Massey, Ruth C

    2008-05-01

    The extracellular adhesion protein (Eap) secreted by the major human pathogen Staphylococcus aureus is known to have several effects on human immunity. We have recently added to knowledge of these roles by demonstrating that Eap enhances interactions between major histocompatibility complex molecules and human leukocytes. Several studies have indicated that Eap can induce cytokine production by human peripheral blood mononuclear cells (PBMCs). To date, there has been no rigorous attempt to identify the breadth of cytokines produced by Eap stimulation or to identify the cell subsets that respond. Here, we demonstrate that Eap induces the secretion of the proinflammatory cytokines interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) by CD14(+) leukocytes (monocytes and macrophages) within direct ex vivo PBMC populations (note that granulocytes are also CD14(+) but are largely depleted from PBMC preparations). Anti-intercellular adhesion molecule 1 (CD54) antibodies inhibited this induction and implicated a role for this known Eap binding protein in cellular activation. IL-6 and TNF-alpha secretion by murine cells exposed to Eap was also observed. The activation of CD14(+) cells by Eap suggests that it could play a significant role in both septic shock and fever, two of the major pathological features of S. aureus infections.

  10. Modulation of mitogen-activated protein kinase-activated protein kinase 3 by hepatitis C virus core protein

    DEFF Research Database (Denmark)

    Ngo, HT; Pham, Long; Kim, JW

    2013-01-01

    Hepatitis C virus (HCV) is highly dependent on cellular proteins for its own propagation. In order to identify the cellular factors involved in HCV propagation, we performed protein microarray assays using the HCV core protein as a probe. Of ~9,000 host proteins immobilized in a microarray...... inducers. Binding of HCV core to MAPKAPK3 was confirmed by in vitro pulldown assay and further verified by coimmunoprecipitation assay. HCV core protein interacted with MAPKAPK3 through amino acid residues 41 to 75 of core and the N-terminal half of kinase domain of MAPKAPK3. In addition, both RNA...... increased HCV IRES-mediated translation and MAPKAPK3-dependent HCV IRES activity was further increased by core protein. These data suggest that HCV core may modulate MAPKAPK3 to facilitate its own propagation....

  11. Development of an efficient E. coli expression and purification system for a catalytically active, human Cullin3-RINGBox1 protein complex and elucidation of its quaternary structure with Keap1

    International Nuclear Information System (INIS)

    Small, Evan; Eggler, Aimee; Mesecar, Andrew D.

    2010-01-01

    Research highlights: → A novel expression strategy was used to purify Cul3-Rbx1 from E. coli. → The Cul3-Rbx1 complex is fully active and catalyzes ubiquitination of Nrf2 in vitro. → Cul3, Rbx1, and Keap1 form a complex with unique stoichiometry of 1:1:2. -- Abstract: The Cullin3-based E3 ubiquitin ligase complex is thought to play an important role in the cellular response to oxidative stress and xenobiotic assault. While limited biochemical studies of the ligase's role in these complex signaling pathways are beginning to emerge, structural studies are lagging far behind due to the inability to acquire sufficient quantities of full-length, highly pure and active Cullin3. Here we describe the design and construction of an optimized expression and purification system for the full-length, human Cullin3-RINGBox 1 (Rbx1) protein complex from Escherichia coli. The dual-expression system is comprised of codon-optimized Cullin3 and Rbx1 genes co-expressed from a single pET-Duet-1 plasmid. Rapid purification of the Cullin3-Rbx1 complex is achieved in two steps via an affinity column followed by size-exclusion chromatography. Approximately 15 mg of highly pure and active Cullin3-Rbx1 protein from 1 L of E. coli culture can be achieved. Analysis of the quaternary structure of the Cullin3-Rbx1 and Cullin3-Rbx1-Keap1 complexes by size-exclusion chromatography and analytical ultracentrifugation indicates a 1:1 stoichiometry for the Cullin3-Rbx1 complex (MW = 111 kDa), and a 1:1:2 stoichiometry for the Cullin3-Rbx1-Keap1 complex (MW = 280 kDa). This latter complex has a novel quaternary structural organization for cullin E3 ligases, and it is fully active based on an in vitro Cullin3-Rbx1-Keap1-Nrf2 ubiquitination activity assay that was developed and optimized in this study.

  12. Development of an efficient E. coli expression and purification system for a catalytically active, human Cullin3-RINGBox1 protein complex and elucidation of its quaternary structure with Keap1

    Energy Technology Data Exchange (ETDEWEB)

    Small, Evan [Department of Biochemistry, University of Illinois at Chicago, Chicago, IL 60607 (United States); Eggler, Aimee [Department of Biological Sciences, Purdue University, 240 S. Martin Jischke Drive, West Lafayette, IN 47907-1971 (United States); Mesecar, Andrew D., E-mail: amesecar@purdue.edu [Department of Biological Sciences, Purdue University, 240 S. Martin Jischke Drive, West Lafayette, IN 47907-1971 (United States)

    2010-10-01

    Research highlights: {yields} A novel expression strategy was used to purify Cul3-Rbx1 from E. coli. {yields} The Cul3-Rbx1 complex is fully active and catalyzes ubiquitination of Nrf2 in vitro. {yields} Cul3, Rbx1, and Keap1 form a complex with unique stoichiometry of 1:1:2. -- Abstract: The Cullin3-based E3 ubiquitin ligase complex is thought to play an important role in the cellular response to oxidative stress and xenobiotic assault. While limited biochemical studies of the ligase's role in these complex signaling pathways are beginning to emerge, structural studies are lagging far behind due to the inability to acquire sufficient quantities of full-length, highly pure and active Cullin3. Here we describe the design and construction of an optimized expression and purification system for the full-length, human Cullin3-RINGBox 1 (Rbx1) protein complex from Escherichia coli. The dual-expression system is comprised of codon-optimized Cullin3 and Rbx1 genes co-expressed from a single pET-Duet-1 plasmid. Rapid purification of the Cullin3-Rbx1 complex is achieved in two steps via an affinity column followed by size-exclusion chromatography. Approximately 15 mg of highly pure and active Cullin3-Rbx1 protein from 1 L of E. coli culture can be achieved. Analysis of the quaternary structure of the Cullin3-Rbx1 and Cullin3-Rbx1-Keap1 complexes by size-exclusion chromatography and analytical ultracentrifugation indicates a 1:1 stoichiometry for the Cullin3-Rbx1 complex (MW = 111 kDa), and a 1:1:2 stoichiometry for the Cullin3-Rbx1-Keap1 complex (MW = 280 kDa). This latter complex has a novel quaternary structural organization for cullin E3 ligases, and it is fully active based on an in vitro Cullin3-Rbx1-Keap1-Nrf2 ubiquitination activity assay that was developed and optimized in this study.

  13. Complement activation by ceramide transporter proteins.

    Science.gov (United States)

    Bode, Gerard H; Losen, Mario; Buurman, Wim A; Veerhuis, Robert; Molenaar, Peter C; Steinbusch, Harry W M; De Baets, Marc H; Daha, Mohamed R; Martinez-Martinez, Pilar

    2014-02-01

    C1q is the initiator of the classical complement pathway and, as such, is essential for efficient opsonization and clearance of pathogens, altered self-structures, and apoptotic cells. The ceramide transporter protein (CERT) and its longer splicing isoform CERTL are known to interact with extracellular matrix components, such as type IV collagen, and with the innate immune protein serum amyloid P. In this article, we report a novel function of CERT in the innate immune response. Both CERT isoforms, when immobilized, were found to bind the globular head region of C1q and to initiate the classical complement pathway, leading to activation of C4 and C3, as well as generation of the membrane attack complex C5b-9. In addition, C1q was shown to bind to endogenous CERTL on the surface of apoptotic cells. These results demonstrate the role of CERTs in innate immunity, especially in the clearance of apoptotic cells.

  14. Quantitation of glial fibrillary acidic protein in human brain tumours

    DEFF Research Database (Denmark)

    Rasmussen, S; Bock, E; Warecka, K

    1980-01-01

    The glial fibrillary acidic protein (GFA) content of 58 human brain tumours was determined by quantitative immunoelectrophoresis, using monospecific antibody against GFA. Astrocytomas, glioblastomas, oligodendrogliomas, spongioblastomas, ependymomas and medulloblastomas contained relatively high...

  15. Protein buffering in model systems and in whole human saliva.

    Directory of Open Access Journals (Sweden)

    Andreas Lamanda

    Full Text Available The aim of this study was to quantify the buffer attributes (value, power, range and optimum of two model systems for whole human resting saliva, the purified proteins from whole human resting saliva and single proteins. Two model systems, the first containing amyloglucosidase and lysozyme, and the second containing amyloglucosidase and alpha-amylase, were shown to provide, in combination with hydrogencarbonate and di-hydrogenphosphate, almost identical buffer attributes as whole human resting saliva. It was further demonstrated that changes in the protein concentration as small as 0.1% may change the buffer value of a buffer solution up to 15 times. Additionally, it was shown that there was a protein concentration change in the same range (0.16% between saliva samples collected at the time periods of 13:00 and others collected at 9:00 am and 17:00. The mode of the protein expression changed between these samples corresponded to the change in basic buffer power and the change of the buffer value at pH 6.7. Finally, SDS Page and Ruthenium II tris (bathophenantroline disulfonate staining unveiled a constant protein expression in all samples except for one 50 kDa protein band. As the change in the expression pattern of that 50 kDa protein band corresponded to the change in basic buffer power and the buffer value at pH 6.7, it was reasonable to conclude that this 50 kDa protein band may contain the protein(s belonging to the protein buffer system of human saliva.

  16. Protein biosynthesis in isolated human scalp hair follicles.

    Science.gov (United States)

    Vermorken, A J; Weterings, P J; Bloemendal, H

    1979-02-15

    The present study demonstrates that protein biosynthesis can be studied in single isolated human scalp hair follicles. The matrix and the sheath are the main regions where amino acids are built in. Incorporation is linear for at least five hours. The newly synthesized proteins can be separated into a water-soluble, a urea-soluble and a urea-insoluble fraction. Product analysis has been performed on the first two fractions, revealing different protein patterns.

  17. Complete cDNA sequence coding for human docking protein

    Energy Technology Data Exchange (ETDEWEB)

    Hortsch, M; Labeit, S; Meyer, D I

    1988-01-11

    Docking protein (DP, or SRP receptor) is a rough endoplasmic reticulum (ER)-associated protein essential for the targeting and translocation of nascent polypeptides across this membrane. It specifically interacts with a cytoplasmic ribonucleoprotein complex, the signal recognition particle (SRP). The nucleotide sequence of cDNA encoding the entire human DP and its deduced amino acid sequence are given.

  18. Small GTP-binding proteins in human endothelial cells

    NARCIS (Netherlands)

    de Leeuw, H. P.; Koster, P. M.; Calafat, J.; Janssen, H.; van Zonneveld, A. J.; van Mourik, J. A.; Voorberg, J.

    1998-01-01

    Small GTP-binding proteins of the Ras superfamily control an extensive number of intracellular events by alternating between GDP- and GTP-bound conformation. The presence of members of this protein family was examined in human umbilical vein endothelial cells employing RT-PCR. Sequence analysis of

  19. In vivo extracellular matrix protein expression by human periodontal ...

    African Journals Online (AJOL)

    It is well known that the orthodontic force applied to teeth generates a series of events that remodel the periodontal ligament (PDL). Extracellular matrix proteins (ECM) are described as molecular regulators of these events. However, the exact contribution of these proteins in human PDL modeling by orthodontic force ...

  20. A Review of Human Activity Recognition Methods

    Directory of Open Access Journals (Sweden)

    Michalis eVrigkas

    2015-11-01

    Full Text Available Recognizing human activities from video sequences or still images is a challenging task due to problems such as background clutter, partial occlusion, changes in scale, viewpoint, lighting, and appearance. Many applications, including video surveillance systems, human-computer interaction, and robotics for human behavior characterization, require a multiple activity recognition system. In this work, we provide a detailed review of recent and state-of-the-art research advances in the field of human activity classification. We propose a categorization of human activity methodologies and discuss their advantages and limitations. In particular, we divide human activity classification methods into two large categories according to whether they use data from different modalities or not. Then, each of these categories is further analyzed into sub-categories, which reflect how they model human activities and what type of activities they are interested in. Moreover, we provide a comprehensive analysis of the existing, publicly available human activity classification datasets and examine the requirements for an ideal human activity recognition dataset. Finally, we report the characteristics of future research directions and present some open issues on human activity recognition.

  1. Protein dynamics in individual human cells: experiment and theory.

    Directory of Open Access Journals (Sweden)

    Ariel Aharon Cohen

    Full Text Available A current challenge in biology is to understand the dynamics of protein circuits in living human cells. Can one define and test equations for the dynamics and variability of a protein over time? Here, we address this experimentally and theoretically, by means of accurate time-resolved measurements of endogenously tagged proteins in individual human cells. As a model system, we choose three stable proteins displaying cell-cycle-dependant dynamics. We find that protein accumulation with time per cell is quadratic for proteins with long mRNA life times and approximately linear for a protein with short mRNA lifetime. Both behaviors correspond to a classical model of transcription and translation. A stochastic model, in which genes slowly switch between ON and OFF states, captures measured cell-cell variability. The data suggests, in accordance with the model, that switching to the gene ON state is exponentially distributed and that the cell-cell distribution of protein levels can be approximated by a Gamma distribution throughout the cell cycle. These results suggest that relatively simple models may describe protein dynamics in individual human cells.

  2. Activation of human herpesvirus replication by apoptosis.

    Science.gov (United States)

    Prasad, Alka; Remick, Jill; Zeichner, Steven L

    2013-10-01

    A central feature of herpesvirus biology is the ability of herpesviruses to remain latent within host cells. Classically, exposure to inducing agents, like activating cytokines or phorbol esters that stimulate host cell signal transduction events, and epigenetic agents (e.g., butyrate) was thought to end latency. We recently showed that Kaposi's sarcoma-associated herpesvirus (KSHV, or human herpesvirus-8 [HHV-8]) has another, alternative emergency escape replication pathway that is triggered when KSHV's host cell undergoes apoptosis, characterized by the lack of a requirement for the replication and transcription activator (RTA) protein, accelerated late gene kinetics, and production of virus with decreased infectivity. Caspase-3 is necessary and sufficient to initiate the alternative replication program. HSV-1 was also recently shown to initiate replication in response to host cell apoptosis. These observations suggested that an alternative apoptosis-triggered replication program might be a general feature of herpesvirus biology and that apoptosis-initiated herpesvirus replication may have clinical implications, particularly for herpesviruses that almost universally infect humans. To explore whether an alternative apoptosis-initiated replication program is a common feature of herpesvirus biology, we studied cell lines latently infected with Epstein-Barr virus/HHV-4, HHV-6A, HHV-6B, HHV-7, and KSHV. We found that apoptosis triggers replication for each HHV studied, with caspase-3 being necessary and sufficient for HHV replication. An alternative apoptosis-initiated replication program appears to be a common feature of HHV biology. We also found that commonly used cytotoxic chemotherapeutic agents activate HHV replication, which suggests that treatments that promote apoptosis may lead to activation of latent herpesviruses, with potential clinical significance.

  3. Main Strategies of Plant Expression System Glycoengineering for Producing Humanized Recombinant Pharmaceutical Proteins.

    Science.gov (United States)

    Rozov, S M; Permyakova, N V; Deineko, E V

    2018-03-01

    Most the pharmaceutical proteins are derived not from their natural sources, rather their recombinant analogs are synthesized in various expression systems. Plant expression systems, unlike mammalian cell cultures, combine simplicity and low cost of procaryotic systems and the ability for posttranslational modifications inherent in eucaryotes. More than 50% of all human proteins and more than 40% of the currently used pharmaceutical proteins are glycosylated, that is, they are glycoproteins, and their biological activity, pharmacodynamics, and immunogenicity depend on the correct glycosylation pattern. This review examines in detail the similarities and differences between N- and O-glycosylation in plant and mammalian cells, as well as the effect of plant glycans on the activity, pharmacokinetics, immunity, and intensity of biosynthesis of pharmaceutical proteins. The main current strategies of glycoengineering of plant expression systems aimed at obtaining fully humanized proteins for pharmaceutical application are summarized.

  4. Protein covalent modification by biologically active quinones

    Directory of Open Access Journals (Sweden)

    MIROSLAV J. GASIC

    2004-11-01

    Full Text Available The avarone/avarol quinone/hydroquinone couple shows considerable antitumor activity. In this work, covalent modification of b-lactoglobulin by avarone and its derivatives as well as by the synthetic steroidal quinone 2,5(10-estradiene-1,4,17-trione and its derivatives were studied. The techniques for studying chemical modification of b-lactoglobulin by quinones were: UV/Vis spectrophotometry, SDS PAGE and isoelectrofocusing. SDS PAGE results suggest that polymerization of the protein occurs. It could be seen that the protein of 18 kD gives the bands of 20 kD, 36 kD, 40 kD, 45 kD, 64 kD and 128 kD depending on modification agent. The shift of the pI of the protein (5.4 upon modification toward lower values (from pI 5.0 to 5.3 indicated that lysine amino groups are the principal site of the reaction of b-lactoglobulin with the quinones.

  5. Functional similarities between the dictyostelium protein AprA and the human protein dipeptidyl‐peptidase IV

    Science.gov (United States)

    Herlihy, Sarah E.; Tang, Yu; Phillips, Jonathan E.

    2017-01-01

    Abstract Autocrine proliferation repressor protein A (AprA) is a protein secreted by Dictyostelium discoideum cells. Although there is very little sequence similarity between AprA and any human protein, AprA has a predicted structural similarity to the human protein dipeptidyl peptidase IV (DPPIV). AprA is a chemorepellent for Dictyostelium cells, and DPPIV is a chemorepellent for neutrophils. This led us to investigate if AprA and DPPIV have additional functional similarities. We find that like AprA, DPPIV is a chemorepellent for, and inhibits the proliferation of, D. discoideum cells, and that AprA binds some DPPIV binding partners such as fibronectin. Conversely, rAprA has DPPIV‐like protease activity. These results indicate a functional similarity between two eukaryotic chemorepellent proteins with very little sequence similarity, and emphasize the usefulness of using a predicted protein structure to search a protein structure database, in addition to searching for proteins with similar sequences. PMID:28028841

  6. G protein-coupled receptor mutations and human genetic disease.

    Science.gov (United States)

    Thompson, Miles D; Hendy, Geoffrey N; Percy, Maire E; Bichet, Daniel G; Cole, David E C

    2014-01-01

    Genetic variations in G protein-coupled receptor genes (GPCRs) disrupt GPCR function in a wide variety of human genetic diseases. In vitro strategies and animal models have been used to identify the molecular pathologies underlying naturally occurring GPCR mutations. Inactive, overactive, or constitutively active receptors have been identified that result in pathology. These receptor variants may alter ligand binding, G protein coupling, receptor desensitization and receptor recycling. Receptor systems discussed include rhodopsin, thyrotropin, parathyroid hormone, melanocortin, follicle-stimulating hormone (FSH), luteinizing hormone, gonadotropin-releasing hormone (GNRHR), adrenocorticotropic hormone, vasopressin, endothelin-β, purinergic, and the G protein associated with asthma (GPRA or neuropeptide S receptor 1 (NPSR1)). The role of activating and inactivating calcium-sensing receptor (CaSR) mutations is discussed in detail with respect to familial hypocalciuric hypercalcemia (FHH) and autosomal dominant hypocalemia (ADH). The CASR mutations have been associated with epilepsy. Diseases caused by the genetic disruption of GPCR functions are discussed in the context of their potential to be selectively targeted by drugs that rescue altered receptors. Examples of drugs developed as a result of targeting GPCRs mutated in disease include: calcimimetics and calcilytics, therapeutics targeting melanocortin receptors in obesity, interventions that alter GNRHR loss from the cell surface in idiopathic hypogonadotropic hypogonadism and novel drugs that might rescue the P2RY12 receptor congenital bleeding phenotype. De-orphanization projects have identified novel disease-associated receptors, such as NPSR1 and GPR35. The identification of variants in these receptors provides genetic reagents useful in drug screens. Discussion of the variety of GPCRs that are disrupted in monogenic Mendelian disorders provides the basis for examining the significance of common

  7. Pharmacokinetics of activated protein C in guinea pigs

    International Nuclear Information System (INIS)

    Berger, H. Jr.; Kirstein, C.G.; Orthner, C.L.

    1991-01-01

    Protein C is a vitamin K-dependent zymogen of the serine protease, activated protein C (APC), an important regulatory enzyme in hemostasis. In view of the potential of human APC as an anticoagulant and profibrinolytic agent, the pharmacokinetics and tissue distribution of APC were studied in guinea pigs. The plasma elimination of a trace dose of 125 I-APC was biphasic following an initial rapid elimination of approximately 15% of the injected dose within 1 to 2 minutes. This rapid removal of 125 I-APC from the circulation was found to be a result of an association with the liver regardless of the route of injection. Essentially identical results were obtained with active site-blocked forms of APC generated with either diisopropylfluorophosphate or D-phenylalanyl-L-prolyl-L-arginine chloromethyl ketone, which indicates that the active site was not essential for the liver association. Accumulation of all three forms of APC in the liver peaked at 30 minutes and then declined as increasing amounts of degraded radiolabeled material appeared in the gastrointestinal tract and urine. Removal of the gamma-carboxyglutamic acid (gla) domain of diisopropylphosphoryl-APC resulted in a 50% reduction in the association with liver and an accumulation in the kidneys. Protein C and protein S were cleared from the circulation at rates approximately one-half and one-fourth, respectively, that of APC. Both in vitro and in vivo, APC was found to form complexes with protease inhibitors present in guinea pig plasma. Complex formation resulted in a more rapid disappearance of the enzymatic activity of APC than elimination of the protein moiety. These findings indicate two distinct mechanisms for the elimination of APC. One mechanism involves reaction with plasma protease inhibitors and subsequent elimination by specific hepatic receptors. (Abstract Truncated)

  8. Annotating activation/inhibition relationships to protein-protein interactions using gene ontology relations.

    Science.gov (United States)

    Yim, Soorin; Yu, Hasun; Jang, Dongjin; Lee, Doheon

    2018-04-11

    Signaling pathways can be reconstructed by identifying 'effect types' (i.e. activation/inhibition) of protein-protein interactions (PPIs). Effect types are composed of 'directions' (i.e. upstream/downstream) and 'signs' (i.e. positive/negative), thereby requiring directions as well as signs of PPIs to predict signaling events from PPI networks. Here, we propose a computational method for systemically annotating effect types to PPIs using relations between functional information of proteins. We used regulates, positively regulates, and negatively regulates relations in Gene Ontology (GO) to predict directions and signs of PPIs. These relations indicate both directions and signs between GO terms so that we can project directions and signs between relevant GO terms to PPIs. Independent test results showed that our method is effective for predicting both directions and signs of PPIs. Moreover, our method outperformed a previous GO-based method that did not consider the relations between GO terms. We annotated effect types to human PPIs and validated several highly confident effect types against literature. The annotated human PPIs are available in Additional file 2 to aid signaling pathway reconstruction and network biology research. We annotated effect types to PPIs by using regulates, positively regulates, and negatively regulates relations in GO. We demonstrated that those relations are effective for predicting not only signs, but also directions of PPIs. The usefulness of those relations suggests their potential applications to other types of interactions such as protein-DNA interactions.

  9. Computational Prediction of Human Salivary Proteins from Blood Circulation and Application to Diagnostic Biomarker Identification

    Science.gov (United States)

    Wang, Jiaxin; Liang, Yanchun; Wang, Yan; Cui, Juan; Liu, Ming; Du, Wei; Xu, Ying

    2013-01-01

    Proteins can move from blood circulation into salivary glands through active transportation, passive diffusion or ultrafiltration, some of which are then released into saliva and hence can potentially serve as biomarkers for diseases if accurately identified. We present a novel computational method for predicting salivary proteins that come from circulation. The basis for the prediction is a set of physiochemical and sequence features we found to be discerning between human proteins known to be movable from circulation to saliva and proteins deemed to be not in saliva. A classifier was trained based on these features using a support-vector machine to predict protein secretion into saliva. The classifier achieved 88.56% average recall and 90.76% average precision in 10-fold cross-validation on the training data, indicating that the selected features are informative. Considering the possibility that our negative training data may not be highly reliable (i.e., proteins predicted to be not in saliva), we have also trained a ranking method, aiming to rank the known salivary proteins from circulation as the highest among the proteins in the general background, based on the same features. This prediction capability can be used to predict potential biomarker proteins for specific human diseases when coupled with the information of differentially expressed proteins in diseased versus healthy control tissues and a prediction capability for blood-secretory proteins. Using such integrated information, we predicted 31 candidate biomarker proteins in saliva for breast cancer. PMID:24324552

  10. Human-specific protein isoforms produced by novel splice sites in the human genome after the human-chimpanzee divergence

    Directory of Open Access Journals (Sweden)

    Kim Dong Seon

    2012-11-01

    Full Text Available Abstract Background Evolution of splice sites is a well-known phenomenon that results in transcript diversity during human evolution. Many novel splice sites are derived from repetitive elements and may not contribute to protein products. Here, we analyzed annotated human protein-coding exons and identified human-specific splice sites that arose after the human-chimpanzee divergence. Results We analyzed multiple alignments of the annotated human protein-coding exons and their respective orthologous mammalian genome sequences to identify 85 novel splice sites (50 splice acceptors and 35 donors in the human genome. The novel protein-coding exons, which are expressed either constitutively or alternatively, produce novel protein isoforms by insertion, deletion, or frameshift. We found three cases in which the human-specific isoform conferred novel molecular function in the human cells: the human-specific IMUP protein isoform induces apoptosis of the trophoblast and is implicated in pre-eclampsia; the intronization of a part of SMOX gene exon produces inactive spermine oxidase; the human-specific NUB1 isoform shows reduced interaction with ubiquitin-like proteins, possibly affecting ubiquitin pathways. Conclusions Although the generation of novel protein isoforms does not equate to adaptive evolution, we propose that these cases are useful candidates for a molecular functional study to identify proteomic changes that might bring about novel phenotypes during human evolution.

  11. Stapled peptides as a new technology to investigate protein-protein interactions in human platelets.

    Science.gov (United States)

    Iegre, Jessica; Ahmed, Niaz S; Gaynord, Josephine S; Wu, Yuteng; Herlihy, Kara M; Tan, Yaw Sing; Lopes-Pires, Maria E; Jha, Rupam; Lau, Yu Heng; Sore, Hannah F; Verma, Chandra; O' Donovan, Daniel H; Pugh, Nicholas; Spring, David R

    2018-05-28

    Platelets are blood cells with numerous crucial pathophysiological roles in hemostasis, cardiovascular thrombotic events and cancer metastasis. Platelet activation requires the engagement of intracellular signalling pathways that involve protein-protein interactions (PPIs). A better understanding of these pathways is therefore crucial for the development of selective anti-platelet drugs. New strategies for studying PPIs in human platelets are required to overcome limitations associated with conventional platelet research methods. For example, small molecule inhibitors can lack selectivity and are often difficult to design and synthesise. Additionally, development of transgenic animal models is costly and time-consuming and conventional recombinant techniques are ineffective due to the lack of a nucleus in platelets. Herein, we describe the generation of a library of novel, functionalised stapled peptides and their first application in the investigation of platelet PPIs. Moreover, the use of platelet-permeable stapled Bim BH3 peptides confirms the part of Bim in phosphatidyl-serine (PS) exposure and reveals a role for the Bim protein in platelet activatory processes. Our work demonstrates that functionalised stapled peptides are a complementary alternative to conventional platelet research methods, and could make a significant contribution to the understanding of platelet signalling pathways and hence to the development of anti-platelet drugs.

  12. Antioxidative Activity of Tobacco Leaf Protein Hydrolysates

    Directory of Open Access Journals (Sweden)

    Guohua Rao

    2007-01-01

    Full Text Available Discarded tobacco leaf protein hydrolysate (DTLPH was prepared by enzymatic hydrolysis using papain and then separated using ultrafiltration (UF membranes with molecular mass cut-off (MMCO of 10, 5, 3 and 1 kDa. Four permeate fractions including 10-K, 5-K, 3-K and 1-K (the permeate fractions from 10, 5, 3 and 1 kDa hydrolysate fractions were obtained. The 5-K hydrolysate fraction had high oxidation inhibilitory ratio (42.62 %, which was about twofold higher than the original hydrolysate and as high as that of vitamin E (α-tocopherol. The fractionated hydrolysates were superior to the original hydrolysate in the antioxidative activity tested. Moreover, these separated hydrolysates showed the enhanced functional property. The amino acid composition of 5-K hydrolysate was analyzed and the results show that the high antioxidative activity of 5-K hydrolysate was derived from high content of histidine, methionine, cystine and tryptophan.

  13. Prediction of protein-protein interactions between viruses and human by an SVM model

    Directory of Open Access Journals (Sweden)

    Cui Guangyu

    2012-05-01

    Full Text Available Abstract Background Several computational methods have been developed to predict protein-protein interactions from amino acid sequences, but most of those methods are intended for the interactions within a species rather than for interactions across different species. Methods for predicting interactions between homogeneous proteins are not appropriate for finding those between heterogeneous proteins since they do not distinguish the interactions between proteins of the same species from those of different species. Results We developed a new method for representing a protein sequence of variable length in a frequency vector of fixed length, which encodes the relative frequency of three consecutive amino acids of a sequence. We built a support vector machine (SVM model to predict human proteins that interact with virus proteins. In two types of viruses, human papillomaviruses (HPV and hepatitis C virus (HCV, our SVM model achieved an average accuracy above 80%, which is higher than that of another SVM model with a different representation scheme. Using the SVM model and Gene Ontology (GO annotations of proteins, we predicted new interactions between virus proteins and human proteins. Conclusions Encoding the relative frequency of amino acid triplets of a protein sequence is a simple yet powerful representation method for predicting protein-protein interactions across different species. The representation method has several advantages: (1 it enables a prediction model to achieve a better performance than other representations, (2 it generates feature vectors of fixed length regardless of the sequence length, and (3 the same representation is applicable to different types of proteins.

  14. Anticancer Activity of Bacterial Proteins and Peptides.

    Science.gov (United States)

    Karpiński, Tomasz M; Adamczak, Artur

    2018-04-30

    Despite much progress in the diagnosis and treatment of cancer, tumour diseases constitute one of the main reasons of deaths worldwide. The side effects of chemotherapy and drug resistance of some cancer types belong to the significant current therapeutic problems. Hence, searching for new anticancer substances and medicines are very important. Among them, bacterial proteins and peptides are a promising group of bioactive compounds and potential anticancer drugs. Some of them, including anticancer antibiotics (actinomycin D, bleomycin, doxorubicin, mitomycin C) and diphtheria toxin, are already used in the cancer treatment, while other substances are in clinical trials (e.g., p28, arginine deiminase ADI) or tested in in vitro research. This review shows the current literature data regarding the anticancer activity of proteins and peptides originated from bacteria: antibiotics, bacteriocins, enzymes, nonribosomal peptides (NRPs), toxins and others such as azurin, p28, Entap and Pep27anal2. The special attention was paid to the still poorly understood active substances obtained from the marine sediment bacteria. In total, 37 chemical compounds or groups of compounds with antitumor properties have been described in the present article.

  15. Human neuroglobin protein in cerebrospinal fluid

    Directory of Open Access Journals (Sweden)

    Whalen Gail

    2005-02-01

    Full Text Available Abstract Background Neuroglobin is a hexacoordinated member of the globin family of proteins. It is predominantly localized to various brain regions and retina where it may play a role in protection against ischemia and nitric oxide-induced neural injury. Cerebrospinal fluid was collected from 12 chronic regional or systemic pain and 5 control subjects. Proteins were precipitated by addition of 50% 0.2 N acetic acid, 50% ethanol, 0.02% sodium bisulfite. The pellet was extensively digested with trypsin. Peptides were separated by capillary liquid chromatography using a gradient from 95% water to 95% acetonitrile in 0.2% formic acid, and eluted through a nanoelectrospray ionization interface into a quadrapole – time-of-flight dual mass spectrometer (QToF2, Waters, Milford, MA. Peptides were sequenced (PepSeq, MassLynx v3.5 and proteins identified using MASCOT ®. Results Six different neuroglobin peptides were identified in various combinations in 3 of 9 female pain subjects, but none in male pain, or female or male control subjects. Conclusion This is the first description of neuroglobin in cerebrospinal fluid. The mechanism(s leading to its release in chronic pain states remain to be defined.

  16. Determination of human muscle protein fractional synthesis rate

    DEFF Research Database (Denmark)

    Bornø, Andreas; Hulston, Carl J; van Hall, Gerrit

    2014-01-01

    In the present study, different MS methods for the determination of human muscle protein fractional synthesis rate (FSR) using [ring-(13)C6 ]phenylalanine as a tracer were evaluated. Because the turnover rate of human skeletal muscle is slow, only minute quantities of the stable isotopically...

  17. Guidelines for the nomenclature of the human heat shock proteins

    NARCIS (Netherlands)

    Kampinga, Harm H.; Hageman, Jurre; Vos, Michel J.; Kubota, Hiroshi; Tanguay, Robert M.; Bruford, Elspeth A.; Cheetham, Michael E.; Chen, B.; Hightower, Lawrence E.

    The expanding number of members in the various human heat shock protein (HSP) families and the inconsistencies in their nomenclature have often led to confusion. Here, we propose new guidelines for the nomenclature of the human HSP families, HSPH (HSP110), HSPC (HSP90), HSPA (HSP70), DNAJ (HSP40),

  18. Protein phosphatase 5 promotes hepatocarcinogenesis through interaction with AMP-activated protein kinase.

    Science.gov (United States)

    Chen, Yao-Li; Hung, Man-Hsin; Chu, Pei-Yi; Chao, Tzu-I; Tsai, Ming-Hsien; Chen, Li-Ju; Hsiao, Yung-Jen; Shih, Chih-Ting; Hsieh, Feng-Shu; Chen, Kuen-Feng

    2017-08-15

    The serine-threonine protein phosphatase family members are known as critical regulators of various cellular functions, such as survival and transformation. Growing evidence suggests that pharmacological manipulation of phosphatase activity exhibits therapeutic benefits. Ser/Thr protein phosphatase 5 (PP5) is known to participate in glucocorticoid receptor (GR) and stress-induced signaling cascades that regulate cell growth and apoptosis, and has been shown to be overexpressed in various human malignant diseases. However, the role of PP5 in hepatocellular carcinoma (HCC) and whether PP5 may be a viable therapeutic target for HCC treatment are unknown. Here, by analyzing HCC clinical samples obtained from 215 patients, we found that overexpression of PP5 is tumor specific and associated with worse clinical outcomes. We further characterized the oncogenic properties of PP5 in HCC cells. Importantly, both silencing of PP5 with lentiviral-mediated short hairpin RNA (shRNA) and chemical inhibition of PP5 phosphatase activity using the natural compound cantharidin/norcantharidin markedly suppressed the growth of HCC cells and tumors in vitro and in vivo. Moreover, we identified AMP-activated protein kinase (AMPK) as a novel downstream target of oncogenic PP5 and demonstrated that the antitumor mechanisms underlying PP5 inhibition involve activation of AMPK signaling. Overall, our results establish a pathological function of PP5 in hepatocarcinogenesis via affecting AMPK signaling and suggest that PP5 inhibition is an attractive therapeutic approach for HCC. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Comparative Molecular Dynamics Simulations of Mitogen-Activated Protein Kinase-Activated Protein Kinase 5

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    Inger Lindin

    2014-03-01

    Full Text Available The mitogen-activated protein kinase-activated protein kinase MK5 is a substrate of the mitogen-activated protein kinases p38, ERK3 and ERK4. Cell culture and animal studies have demonstrated that MK5 is involved in tumour suppression and promotion, embryogenesis, anxiety, cell motility and cell cycle regulation. In the present study, homology models of MK5 were used for molecular dynamics (MD simulations of: (1 MK5 alone; (2 MK5 in complex with an inhibitor; and (3 MK5 in complex with the interaction partner p38α. The calculations showed that the inhibitor occupied the active site and disrupted the intramolecular network of amino acids. However, intramolecular interactions consistent with an inactive protein kinase fold were not formed. MD with p38α showed that not only the p38 docking region, but also amino acids in the activation segment, αH helix, P-loop, regulatory phosphorylation region and the C-terminal of MK5 may be involved in forming a very stable MK5-p38α complex, and that p38α binding decreases the residual fluctuation of the MK5 model. Electrostatic Potential Surface (EPS calculations of MK5 and p38α showed that electrostatic interactions are important for recognition and binding.

  20. Nuclear pore complex protein mediated nuclear localization of dicer protein in human cells.

    Directory of Open Access Journals (Sweden)

    Yoshinari Ando

    Full Text Available Human DICER1 protein cleaves double-stranded RNA into small sizes, a crucial step in production of single-stranded RNAs which are mediating factors of cytoplasmic RNA interference. Here, we clearly demonstrate that human DICER1 protein localizes not only to the cytoplasm but also to the nucleoplasm. We also find that human DICER1 protein associates with the NUP153 protein, one component of the nuclear pore complex. This association is detected predominantly in the cytoplasm but is also clearly distinguishable at the nuclear periphery. Additional characterization of the NUP153-DICER1 association suggests NUP153 plays a crucial role in the nuclear localization of the DICER1 protein.

  1. Human neuronal cell protein responses to Nipah virus infection

    Directory of Open Access Journals (Sweden)

    Hassan Sharifah

    2007-06-01

    Full Text Available Abstract Background Nipah virus (NiV, a recently discovered zoonotic virus infects and replicates in several human cell types. Its replication in human neuronal cells, however, is less efficient in comparison to other fully susceptible cells. In the present study, the SK-N-MC human neuronal cell protein response to NiV infection is examined using proteomic approaches. Results Method for separation of the NiV-infected human neuronal cell proteins using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE was established. At least 800 protein spots were resolved of which seven were unique, six were significantly up-regulated and eight were significantly down-regulated. Six of these altered proteins were identified using mass spectrometry (MS and confirmed using MS/MS. The heterogenous nuclear ribonucleoprotein (hnRNP F, guanine nucleotide binding protein (G protein, voltage-dependent anion channel 2 (VDAC2 and cytochrome bc1 were present in abundance in the NiV-infected SK-N-MC cells in contrast to hnRNPs H and H2 that were significantly down-regulated. Conclusion Several human neuronal cell proteins that are differentially expressed following NiV infection are identified. The proteins are associated with various cellular functions and their abundance reflects their significance in the cytopathologic responses to the infection and the regulation of NiV replication. The potential importance of the ratio of hnRNP F, and hnRNPs H and H2 in regulation of NiV replication, the association of the mitochondrial protein with the cytopathologic responses to the infection and induction of apoptosis are highlighted.

  2. Antiulcerative Activity of Milk Proteins Hydrolysates.

    Science.gov (United States)

    Carrillo, Wilman; Monteiro, Karin Maia; Martínez-Maqueda, Daniel; Ramos, Mercedes; Recio, Isidra; Carvalho, João Ernesto de

    2018-04-01

    Several studies have shown the protective effect of dairy products, especially α-lactalbumin and derived hydrolysates, against induced gastric ulcerative lesions. The mucus strengthening represents an important mechanism in the defense of gastrointestinal mucosa. Previously, a hydrolysate from casein (CNH) and a hydrolysate from whey protein concentrate rich in β-lactoglobulin (WPH) demonstrated a stimulatory activity on mucus production in intestinal goblet cells. The aim of this work was to evaluate the possible antiulcerative activity of these two hydrolysates in an ethanol-induced ulcer model in rats. All tested samples significantly reduced the ulcerative lesions index (ULI), compared with the saline solution, using doses of 300 and 1000 mg kg -1 body weight with decreases up to 66.3% ULI. A dose-response relationship was found for both hydrolysates. The involvement of endogenous sulfhydryl (SH) groups and prostaglandins (PGs) in the antiulcerative activity was evaluated using their blockage. The antiulcerative activity of WPH showed a drastic decrease in presence of N-ethylmaleimide (from 41.4% to 9.2% ULI). However, the CNH antiulcerative properties were not significantly affected. The cytoprotective effect of WPH appears to depend on a PG-mediated mechanism. In conclusion, CNH and WPH demonstrated in vivo antiulcerative properties and represent a promising alternative as protectors of the gastric mucosa.

  3. The bone morphogenetic protein antagonist gremlin 1 is overexpressed in human cancers and interacts with YWHAH protein

    International Nuclear Information System (INIS)

    Namkoong, Hong; Shin, Seung Min; Kim, Hyun Kee; Ha, Seon-Ah; Cho, Goang Won; Hur, Soo Young; Kim, Tae Eung; Kim, Jin Woo

    2006-01-01

    Basic studies of oncogenesis have demonstrated that either the elevated production of particular oncogene proteins or the occurrence of qualitative abnormalities in oncogenes can contribute to neoplastic cellular transformation. The purpose of our study was to identify an unique gene that shows cancer-associated expression, and characterizes its function related to human carcinogenesis. We used the differential display (DD) RT-PCR method using normal cervical, cervical cancer, metastatic cervical tissues, and cervical cancer cell lines to identify genes overexpressed in cervical cancers and identified gremlin 1 which was overexpressed in cervical cancers. We determined expression levels of gremlin 1 using Northern blot analysis and immunohistochemical study in various types of human normal and cancer tissues. To understand the tumorigenesis pathway of identified gremlin 1 protein, we performed a yeast two-hybrid screen, GST pull down assay, and immunoprecipitation to identify gremlin 1 interacting proteins. DDRT-PCR analysis revealed that gremlin 1 was overexpressed in uterine cervical cancer. We also identified a human gremlin 1 that was overexpressed in various human tumors including carcinomas of the lung, ovary, kidney, breast, colon, pancreas, and sarcoma. PIG-2-transfected HEK 293 cells exhibited growth stimulation and increased telomerase activity. Gremlin 1 interacted with homo sapiens tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein, eta polypeptide (14-3-3 eta; YWHAH). YWHAH protein binding site for gremlin 1 was located between residues 61–80 and gremlin 1 binding site for YWHAH was found to be located between residues 1 to 67. Gremlin 1 may play an oncogenic role especially in carcinomas of the uterine cervix, lung, ovary, kidney, breast, colon, pancreas, and sarcoma. Over-expressed gremlin 1 functions by interaction with YWHAH. Therefore, Gremlin 1 and its binding protein YWHAH could be good targets for developing diagnostic and

  4. Prolactin-inducible proteins in human breast cancer cells

    International Nuclear Information System (INIS)

    Shiu, R.P.; Iwasiow, B.M.

    1985-01-01

    The mechanism of action of prolactin in target cells and the role of prolactin in human breast cancer are poorly understood phenomena. The present study examines the effect of human prolactin (hPRL) on the synthesis of unique proteins by a human breast cancer cell line, T-47D, in serum-free medium containing bovine serum albumin. [ 35 S]Methionine-labeled proteins were analysed by sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis and fluorography. Treatment of cells with hPRL (1-1000 ng/ml) and hydrocortisone (1 microgram/ml) for 36 h or longer resulted in the synthesis and secretion of three proteins having molecular weights of 11,000, 14,000, and 16,000. Neither hPRL nor hydrocortisone alone induced these proteins. Of several other peptide hormones tested, only human growth hormone, a hormone structurally and functionally similar to hPRL, could replace hPRL in causing protein induction. These three proteins were, therefore, referred to as prolactin-inducible proteins (PIP). Each of the three PIPs was purified to homogeneity by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and specific antibodies were generated to them in rabbits. By immunoprecipitation and immunoblotting (Western blot) of proteins secreted by T-47D cells, it was demonstrated that the three PIPs were immunologically identical to one another. In addition, the 16-kDa and 14-kDa proteins (PIP-16 and PIP-14), and not the 11-kDa protein (PIP-11), incorporated [ 3 H]glycosamine. Furthermore, 2-deoxyglucose (2 mM) and tunicamycin (0.5 micrograms/ml), two compounds known to inhibit glycosylation, blocked the production of PIP-16 and PIP-14, with a concomitant increase in the accumulation of PIP-11

  5. Dietary proteins in humans: basic aspects and consumption in Switzerland.

    Science.gov (United States)

    Guigoz, Yves

    2011-03-01

    This introductory review gives an overview on protein metabolism, and discusses protein quality, sources, and requirements as well as the results from recent studies on Swiss spontaneous protein consumption. To assess protein quality in protein mixes and foods, the "protein digestibility-corrected amino acid score" (PDCAAS) is presented as a valuable tool in addition to the biological value (BV). Considering protein intake recommendations, the lower limit recommended has been defined according to the minimal amount needed to maintain short-term nitrogen balance in healthy people with moderate activity. Evaluation of intakes in Switzerland from food consumption data is about 90 g/day of protein per person. Two-thirds of proteins consumed in Switzerland are animal proteins with high biological value [meat and meat products (28 %), milk and dairy products (28 %), fish (3 %), and eggs (3 %)] and about 1/3 of proteins are of plant origin (25 % of cereals, 3 - 4 % of vegetables). Actual spontaneous protein consumption in Switzerland by specific groups of subjects is well within the actual recommendations (10 - 20 % of energy) with only the frail elderly being at risk of not covering their requirements for protein.

  6. Shedding light on proteins, nucleic acids, cells, humans and fish

    Science.gov (United States)

    Setlow, Richard B.

    2002-01-01

    I was trained as a physicist in graduate school. Hence, when I decided to go into the field of biophysics, it was natural that I concentrated on the effects of light on relatively simple biological systems, such as proteins. The wavelengths absorbed by the amino acid subunits of proteins are in the ultraviolet (UV). The wavelengths that affect the biological activities, the action spectra, also are in the UV, but are not necessarily parallel to the absorption spectra. Understanding these differences led me to investigate the action spectra for affecting nucleic acids, and the effects of UV on viruses and cells. The latter studies led me to the discovery of the important molecular nature of the damages affecting DNA (cyclobutane pyrimidine dimers) and to the discovery of nucleotide excision repair. Individuals with the genetic disease xeroderma pigmentosum (XP) are extraordinarily sensitive to sunlight-induced skin cancer. The finding, by James Cleaver, that their skin cells were defective in DNA repair strongly suggested that DNA damage was a key step in carcinogenesis. Such information was important for estimating the wavelengths in sunlight responsible for human skin cancer and for predicting the effects of ozone depletion on the incidence of non-melanoma skin cancer. It took experiments with backcross hybrid fish to call attention to the probable role of the longer UV wavelengths not absorbed by DNA in the induction of melanoma. These reflections trace the biophysicist's path from molecules to melanoma.

  7. Identification of proteins that may directly interact with human RPA.

    Science.gov (United States)

    Nakaya, Ryou; Takaya, Junichiro; Onuki, Takeshi; Moritani, Mariko; Nozaki, Naohito; Ishimi, Yukio

    2010-11-01

    RPA, which consisted of three subunits (RPA1, 2 and 3), plays essential roles in DNA transactions. At the DNA replication forks, RPA binds to single-stranded DNA region to stabilize the structure and to assemble other replication proteins. Interactions between RPA and several replication proteins have been reported but the analysis is not comprehensive. We systematically performed the qualitative analysis to identify RPA interaction partners to understand the protein-protein interaction at the replication forks. We expressed in insect cells the three subunits of human RPA, together with one replication protein, which is present at the forks under normal conditions and/or under the replication stress conditions, to examine the interaction. Among 30 proteins examined in total, it was found that at least 14 proteins interacted with RPA. RPA interacted with MCM3-7, MCM-BP and CDC45 proteins among the proteins that play roles in the initiation and the elongation of the DNA replication. RPA bound with TIPIN, CLASPIN and RAD17, which are involved in the DNA replication checkpoint functions. RPA also bound with cyclin-dependent kinases and an amino-terminal fragment of Rb protein that negatively regulates DNA replication. These results suggest that RPA interacts with the specific proteins among those that play roles in the regulation of the replication fork progression.

  8. Human serum protein and C-reactive protein levels among HIV ...

    African Journals Online (AJOL)

    Human serum protein and C-reactive protein levels were determined among HIV patients visiting St Camillus Hospital, Uromi, Edo State, Nigeria, between January to March, 2013. Fifty (50) HIV patients (20 males; 30 females) and 50 control subjects (24 males; 26 females) were enrolled for this study. The clinical status of ...

  9. The predictive nature of transcript expression levels on protein expression in adult human brain.

    Science.gov (United States)

    Bauernfeind, Amy L; Babbitt, Courtney C

    2017-04-24

    Next generation sequencing methods are the gold standard for evaluating expression of the transcriptome. When determining the biological implications of such studies, the assumption is often made that transcript expression levels correspond to protein levels in a meaningful way. However, the strength of the overall correlation between transcript and protein expression is inconsistent, particularly in brain samples. Following high-throughput transcriptomic (RNA-Seq) and proteomic (liquid chromatography coupled with tandem mass spectrometry) analyses of adult human brain samples, we compared the correlation in the expression of transcripts and proteins that support various biological processes, molecular functions, and that are located in different areas of the cell. Although most categories of transcripts have extremely weak predictive value for the expression of their associated proteins (R 2 values of < 10%), transcripts coding for protein kinases and membrane-associated proteins, including those that are part of receptors or ion transporters, are among those that are most predictive of downstream protein expression levels. The predictive value of transcript expression for corresponding proteins is variable in human brain samples, reflecting the complex regulation of protein expression. However, we found that transcriptomic analyses are appropriate for assessing the expression levels of certain classes of proteins, including those that modify proteins, such as kinases and phosphatases, regulate metabolic and synaptic activity, or are associated with a cellular membrane. These findings can be used to guide the interpretation of gene expression results from primate brain samples.

  10. Type 2 diabetes mellitus is associated with differential effects on plasma cholesteryl ester transfer protein and phospholipid transfer protein activities and concentrations

    NARCIS (Netherlands)

    Dullaart, RPF; De Vries, R; Scheek, L; Borggreve, SE; Van Gent, T; Dallinga-Thie, GM; Ito, M; Nagano, M; Sluiter, WJ; Hattori, H; Van Tol, A

    Background: Human plasma contains two lipid transfer proteins, cholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP), which are crucial in reverse cholesterol transport. Methods: Plasma CETP and PLTP activity levels and concentrations in 16 type 2 diabetic patients and

  11. Human Proteinpedia enables sharing of human protein data

    Energy Technology Data Exchange (ETDEWEB)

    Mathivanan, Suresh; Ahmed, Mukhtar; Ahn, Natalie G.; Alexandre, Hainard; Amanchy, Ramars; Andrews, Philip C.; Bader, Joel S.; Balgley, Brian M.; Bantscheff, Marcus; Bennett, Keiryn; Bjorling, Erik; Blagoev, Blagoy; Bose , Ron; Brahmachari, Samir K.; Burlingame, Alma S.; Bustelo, Xos R.; Cagney, Gerard; Cantin, Greg T; Cardasis, Helene L; Celis, Julio E; Chaerkady, Raghothama; Chu, Feixia; Cole, Phillip A.; Costello, Catherine E; Cotter , Robert J.; Crockett, David; DeLany , James P.; De Marzo, Angelo M; DeSouza, Leroi V; Deutsch, Eric W.; Dransfield , Eric; Drewes , Gerard; Droit , Arnaud; Dunn, Michael; Elenitoba-Johnson, Kojo; Ewing, Rob M.; Van Eyk , Jennifer; Faca , Vitor; Falkner , Jayson; Fang, Xiangming; Fenselau , Catherine; Figeys , Daniel; Gagne , Pierre; Gelfi , Cecilia; Gevaert , Kris; Gimble , Jeffrey; Gnad , Florian; Goel, Renu; Gromov , Pavel; Hanash, Samir M.; Hancock, William S.; Harsha , HC; Hart , Gerald; Faith , Hays; He , Fuchu; Hebbar , Prashantha; Helsens , Kenny; Hermeking , Heiko; Hide , Winston; Hjerno, Karin; Hochstrasser, Denis F.; Hofmann, Oliver; Horn , David M.; Hruban , Ralph H.; Ibarrola , Nieves; James , Peter; Jensen , Ole N.; Jensen, Pia H.; Jung , Peter; Kandasamy, Kumaran; Kheterpal , Indu; Kikuno , Reiko; Korf, Ulrike; Korner, Roman; Kuster, Bernhard; Kwon , Min-Seok; Lee , Hyoung-Joo; Lee , Young - Jin; Lefevre , Michael; Lehvaslaiho, Minna; Lescuyer, Pierre; Levander, Fredrik; Lim, Megan S.; Lobke, Christian; Loo, Joseph; Mann, Matthias; Martens , Lennart; Martinez-Heredia, Juan; McComb, Mark E.; McRedmond , James; Mehrle, Alexander; Menon, Rajasree; Miller, Christine A.; Mischak, Harald; Mohan, S Sujatha; Mohmood , Riaz; Molina , Henrik; Moran , Michael F.; Morgan, James D.; Moritz , Robert; Morzel, Martine; Muddiman, David C.; Nalli , Anuradha; Navarro, J. D.; Neubert , Thomas A.; Ohara , Osamu; Oliva, Rafael; Omenn, Gilbert; Oyama , Masaaki; Paik, Young-Ki; Pennington , Kyla; Pepperkok, Rainer; Periaswamy, Balamurugan; Petricoin, Emanuel F.; Poirier, Guy G.; Prasad, T S Keshava; Purvine, Samuel O.; Rahiman , B Abdul; Ramachandran, Prasanna; Ramachandra , Y L; Rice, Robert H.; Rick , Jens; Ronnholm , Ragna H.; Salonen , Johanna; Sanchez , Jean - Charles; Sayd , Thierry; Seshi, Beerelli; Shankari, Kripa; Sheng , Shi Jun; Shetty , Vivekananda; Shivakumar, K.; Simpson, Richard J.; Sirdeshmukh, Ravi; Siu , K W Michael; Smith, Jeffrey C.; Smith, Richard D.; States, David J.; Sugano, Sumio; Sullivan , Matthew; Superti - Furga, Giulio; Takatalo , Maarit; Thongboonkerd , Visith; Trinidad , Jonathan C.; Uhlen , Mathias; Vandekerckhove, Joel; Vasilescu , Julian; Veenstra, Timothy D.; Vidal - Taboada, Jose - Manuel; Vihinen, Mauno; Wait , Robin; Wang, Xiaoyue; Wiemann, Stefan; Wu , Billy; Xu, Tao; Yates, John R.; Zhong, Jun; Zhou, Ming; Zhu, Yunping; Zurbig, Petra; Pandey, Akhilesh

    2008-02-01

    Proteomic technologies, such as yeast twohybrid, mass spectrometry (MS), protein/ peptide arrays and fluorescence microscopy, yield multi-dimensional data sets, which are often quite large and either not published or published as supplementary information that is not easily searchable. Without a system in place for standardizing and sharing data, it is not fruitful for the biomedical community to contribute these types of data to centralized repositories. Even more difficult is the annotation and display of pertinent information in the context of the corresponding proteins. Wikipedia, an online encyclopedia that anyone can edit, has already proven quite successful1 and can be used as a model for sharing biological data. However, the need for experimental evidence, data standardization and ownership of data creates scientific obstacles.

  12. Detection of cow's milk proteins and minor components in human milk using proteomics techniques.

    Science.gov (United States)

    Coscia, A; Orrù, S; Di Nicola, P; Giuliani, F; Varalda, A; Peila, C; Fabris, C; Conti, A; Bertino, E

    2012-10-01

    Cow's milk proteins (CMPs) are the best characterized food allergens. The aim of this study was to investigate cow's milk allergens in human colostrum of term and preterm newborns' mothers, and other minor protein components by proteomics techniques, more sensitive than other techniques used in the past. Sixty-two term and 11 preterm colostrum samples were collected, subjected to a treatment able to increase the concentration of the most diluted proteins and simultaneously to reduce the concentration of the proteins present at high concentration (Proteominer Treatment), and subsequently subjected to the steps of proteomic techniques. The most relevant finding in this study was the detection of the intact bovine alpha-S1-casein in human colostrum, then bovine alpha-1-casein could be considered the cow's milk allergen that is readily secreted in human milk and could be a cause of sensitization to cow's milk in exclusively breastfed predisposed infants. Another interesting result was the detection, at very low concentrations, of proteins previously not described in human milk (galectin-7, the different isoforms of the 14-3-3 protein and the serum amyloid P-component), probably involved in the regulation of the normal cell growth, in the pro-apoptotic function and in the regulation of tissue homeostasis. Further investigations are needed to understand if these families of proteins have specific biological activity in human milk.

  13. CCAAT/enhancer-binding proteins regulate expression of the human steroidogenic acute regulatory protein (StAR) gene.

    Science.gov (United States)

    Christenson, L K; Johnson, P F; McAllister, J M; Strauss, J F

    1999-09-10

    Two putative CCAAT/enhancer-binding protein (C/EBP) response elements were identified in the proximal promoter of the human steroidogenic acute regulatory protein (StAR) gene, which encodes a key protein-regulating steroid hormone synthesis. Expression of C/EBPalpha and -beta increased StAR promoter activity in COS-1 and HepG2 cells. Cotransfection of C/EBPalpha or -beta and steroidogenic factor 1, a transcription factor required for cAMP regulation of StAR expression, into COS-1 augmented 8-bromoadenosine 3':5'-cyclic monophosphate (8-Br-cAMP)-stimulated promoter activity. When the putative C/EBP response elements were mutated, individually or together, a pronounced decline in basal StAR promoter activity in human granulosa-lutein cells resulted, but the fold stimulation of promoter activity by 8-Br-cAMP was unaffected. Recombinant C/EBPalpha and -beta bound to the two identified sequences but not the mutated elements. Human granulosa-lutein cell nuclear extracts also bound these elements but not the mutated sequences. An antibody to C/EBPbeta, but not C/EBPalpha, supershifted the nuclear protein complex associated with the more distal element. The complex formed by nuclear extracts with the proximal element was not supershifted by either antibody. Western blot analysis revealed the presence of C/EBPalpha and C/EBPbeta in human granulosa-lutein cell nuclear extracts. C/EBPbeta levels were up-regulated 3-fold by 8-Br-cAMP treatment. Our studies demonstrate a role for C/EBPbeta as well as yet to be identified proteins, which can bind to C/EBP response elements, in the regulation of StAR gene expression and suggest a mechanism by which C/EBPbeta participates in the cAMP regulation of StAR gene transcription.

  14. Proteomic characterization of the human centrosome by protein correlation profiling

    DEFF Research Database (Denmark)

    Andersen, Jens S; Wilkinson, Christopher J; Mayor, Thibault

    2003-01-01

    chromosomes between dividing cells. Despite the importance of this organelle to cell biology and more than 100 years of study, many aspects of its function remain enigmatic and its structure and composition are still largely unknown. We performed a mass-spectrometry-based proteomic analysis of human...... centrosomes in the interphase of the cell cycle by quantitatively profiling hundreds of proteins across several centrifugation fractions. True centrosomal proteins were revealed by both correlation with already known centrosomal proteins and in vivo localization. We identified and validated 23 novel...... components and identified 41 likely candidates as well as the vast majority of the known centrosomal proteins in a large background of nonspecific proteins. Protein correlation profiling permits the analysis of any multiprotein complex that can be enriched by fractionation but not purified to homogeneity....

  15. Activated protein synthesis and suppressed protein breakdown signaling in skeletal muscle of critically ill patients.

    Directory of Open Access Journals (Sweden)

    Jakob G Jespersen

    Full Text Available BACKGROUND: Skeletal muscle mass is controlled by myostatin and Akt-dependent signaling on mammalian target of rapamycin (mTOR, glycogen synthase kinase 3β (GSK3β and forkhead box O (FoxO pathways, but it is unknown how these pathways are regulated in critically ill human muscle. To describe factors involved in muscle mass regulation, we investigated the phosphorylation and expression of key factors in these protein synthesis and breakdown signaling pathways in thigh skeletal muscle of critically ill intensive care unit (ICU patients compared with healthy controls. METHODOLOGY/PRINCIPAL FINDINGS: ICU patients were systemically inflamed, moderately hyperglycemic, received insulin therapy, and showed a tendency to lower plasma branched chain amino acids compared with controls. Using Western blotting we measured Akt, GSK3β, mTOR, ribosomal protein S6 kinase (S6k, eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1, and muscle ring finger protein 1 (MuRF1; and by RT-PCR we determined mRNA expression of, among others, insulin-like growth factor 1 (IGF-1, FoxO 1, 3 and 4, atrogin1, MuRF1, interleukin-6 (IL-6, tumor necrosis factor α (TNF-α and myostatin. Unexpectedly, in critically ill ICU patients Akt-mTOR-S6k signaling was substantially higher compared with controls. FoxO1 mRNA was higher in patients, whereas FoxO3, atrogin1 and myostatin mRNAs and MuRF1 protein were lower compared with controls. A moderate correlation (r2=0.36, p<0.05 between insulin infusion dose and phosphorylated Akt was demonstrated. CONCLUSIONS/SIGNIFICANCE: We present for the first time muscle protein turnover signaling in critically ill ICU patients, and we show signaling pathway activity towards a stimulation of muscle protein synthesis and a somewhat inhibited proteolysis.

  16. Mining the human tissue proteome for protein citrullination.

    Science.gov (United States)

    Lee, Chien-Yun; Wang, Dongxue; Wilhelm, Mathias; Zolg, Daniel Paul; Schmidt, Tobias; Schnatbaum, Karsten; Reimer, Ulf; Pontén, Fredrik; Uhlén, Mathias; Hahne, Hannes; Kuster, Bernhard

    2018-04-02

    Citrullination is a post-translational modification of arginine catalyzed by five peptidylarginine deiminases (PADs) in humans. The loss of a positive charge may cause structural or functional alterations and while the modification has been linked to several diseases including rheumatoid arthritis and cancer, its physiological or pathophysiological roles remain largely unclear. In part this is owing to limitations in available methodology able to robustly enrich, detect and localize the modification. As a result, only few citrullination sites have been identified on human proteins with high confidence. In this study, we mined data from mass spectrometry-based deep proteomic profiling of 30 human tissues to identify citrullination sites on endogenous proteins. Database searching of ~70 million tandem mass spectra yielded ~13,000 candidate spectra which were further triaged by spectrum quality metrics and the detection of the specific neutral loss of isocyanic acid from citrullinated peptides to reduce false positives. Because citrullination is easily confused with deamidation, we synthetized ~2,200 citrullinated and 1,300 deamidated peptides to build a library of reference spectra. This led to the validation of 375 citrullination sites on 209 human proteins. Further analysis showed that >80% of the identified modifications sites were new and for 56% of the proteins, citrullination was detected for the first time. Sequence motif analysis revealed a strong preference for Asp and Gly, residues around the citrullination site. Interestingly, while the modification was detected in 26 human tissues with the highest levels found in brain and lung, citrullination levels did not correlate well with protein expression of the PAD enzymes. Even though the current work represents the largest survey of protein citrullination to date, the modification was mostly detected on high abundant proteins arguing that the development of specific enrichment methods would be required in order

  17. Arabinogalactan proteins: focus on carbohydrate active enzymes

    Directory of Open Access Journals (Sweden)

    Eva eKnoch

    2014-06-01

    Full Text Available Arabinogalactan proteins (AGPs are a highly diverse class of cell surface proteoglycans that are commonly found in most plant species. AGPs play important roles in many cellular processes during plant development, such as reproduction, cell proliferation, pattern formation and growth, and in plant-microbe interaction. However, little is known about the molecular mechanisms of their function. Numerous studies using monoclonal antibodies that recognize different AGP glycan epitopes have shown the appearance of a slightly altered AGP glycan in a specific stage of development in plant cells. Therefore, it is anticipated that the biosynthesis and degradation of AGP glycan is tightly regulated during development. Until recently, however, little was known about the enzymes involved in the metabolism of AGP glycans. In this review, we summarize recent discoveries of carbohydrate active enzymes (CAZy; http://www.cazy.org/ involved in the biosynthesis and degradation of AGP glycans, and we discuss the biological role of these enzymes in plant development.

  18. Activated protein C inhibits neutrophil migration in allergic asthma: a randomised trial

    NARCIS (Netherlands)

    de Boer, J. Daan; Berger, Marieke; Majoor, Christof J.; Kager, Liesbeth M.; Meijers, Joost C. M.; Terpstra, Sanne; Nieuwland, Rienk; Boing, Anita N.; Lutter, René; Wouters, Diana; van Mierlo, Gerard J.; Zeerleder, Sacha S.; Bel, Elisabeth H.; van't Veer, Cornelis; de Vos, Alex F.; van der Zee, Jaring S.; van der Poll, Tom

    2015-01-01

    Asthma patients show evidence of a procoagulant state in their airways, accompanied by an impaired function of the anticoagulant protein C system. We aimed to study the effect of recombinant human activated protein C (rhAPC) in allergic asthma patients.We conducted a randomised, double-blind,

  19. Antiviral and antitumor activities of the protein fractions from the ...

    African Journals Online (AJOL)

    In this study, we present the extraction and purification of protein fractions from the larvae of the housefly, Musca domestica. The bioactivities of the protein fractions were indicated by pseudorabies virus (PRV) and human lung cancer cell line A 549. The crude protein fractions had no toxicity to chick embryo fibroblast-like ...

  20. Characterization of a cocaine binding protein in human placenta

    International Nuclear Information System (INIS)

    Ahmed, M.S.; Zhou, D.H.; Maulik, D.; Eldefrawi, M.E.

    1990-01-01

    [ 3 H]-Cocaine binding sites are identified in human placental villus tissue plasma membranes. These binding sites are associated with a protein and show saturable and specific binding of [ 3 H]-cocaine with a high affinity site of 170 fmole/mg protein. The binding is lost with pretreatment with trypsin or heat. The membrane bound protein is solubilized with the detergent 3-(3-cholamidopropyl)dimethyl-ammonio-1-propane sulphonate (CHAPS) with retention of its saturable and specific binding of [ 3 H]-cocaine. The detergent-protein complex migrates on a sepharose CL-6B gel chromatography column as a protein with an apparent molecular weight of 75,900. The protein has an S 20,w value of 5.1. The binding of this protein to norcocaine, pseudococaine, nomifensine, imipramine, desipramine, amphetamine and dopamine indicates that it shares some, but not all, the properties of the brain cocaine receptor. The physiologic significance of this protein in human placenta is currently unclear

  1. Human rights education (HRE) and transnational activism

    NARCIS (Netherlands)

    Mihr, A.; Schmitz, Hans-Peter

    2007-01-01

    Transnational human rights activism occupies today a significant place in the practice and scholarship of current global affairs. This article reviews the past successes and limits of this activism and suggests Human Rights Education (HRE) as a strategic tool currently underutilized by activists and

  2. Monetary reward activates human prefrontal cortex

    International Nuclear Information System (INIS)

    Thut, G.; Roelcke, U.; Nienhusmeier, M.; Missimer, J.; Maguire, R.P.; Leenders, K.L.; Schultz, W.

    1997-01-01

    We present a rCBF PET activation study, in which we demonstrated that reward processing in humans activates a cortical-subcortical network including dorsolateral prefrontal, orbital frontal, thalamic and midbrain regions. It is suggested that, as found for non-human primates, the basal ganglia-thalamo-cortical system is implicated in reward processing. (author) 1 fig., 3 refs

  3. Adenosine monophosphate-activated protein kinase modulates the activated phenotype of hepatic stellate cells.

    Science.gov (United States)

    Caligiuri, Alessandra; Bertolani, Cristiana; Guerra, Cristina Tosti; Aleffi, Sara; Galastri, Sara; Trappoliere, Marco; Vizzutti, Francesco; Gelmini, Stefania; Laffi, Giacomo; Pinzani, Massimo; Marra, Fabio

    2008-02-01

    Adiponectin limits the development of liver fibrosis and activates adenosine monophosphate-activated protein kinase (AMPK). AMPK is a sensor of the cellular energy status, but its possible modulation of the fibrogenic properties of hepatic stellate cells (HSCs) has not been established. In this study, we investigated the role of AMPK activation in the biology of activated human HSCs. A time-dependent activation of AMPK was observed in response to a number of stimuli, including globular adiponectin, 5-aminoimidazole-4-carboxamide-1-beta-4-ribofuranoside (AICAR), or metformin. All these compounds significantly inhibited platelet-derived growth factor (PDGF)-stimulated proliferation and migration of human HSCs and reduced the secretion of monocyte chemoattractant protein-1. In addition, AICAR limited the secretion of type I procollagen. Knockdown of AMPK by gene silencing increased the mitogenic effects of PDGF, confirming the negative modulation exerted by this pathway on HSCs. AMPK activation did not reduce PDGF-dependent activation of extracellular signal-regulated kinase (ERK) or Akt at early time points, whereas a marked inhibition was observed 24 hours after addition of PDGF, reflecting a block in cell cycle progression. In contrast, AICAR blocked short-term phosphorylation of ribosomal S6 kinase (p70(S6K)) and 4E binding protein-1 (4EBP1), 2 downstream effectors of the mammalian target of rapamycin (mTOR) pathway, by PDGF. The ability of interleukin-a (IL-1) to activate nuclear factor kappa B (NF-kappaB) was also reduced by AICAR. Activation of AMPK negatively modulates the activated phenotype of HSCs.

  4. Peptide Mimicrying Between SARS Coronavirus Spike Protein and Human Proteins Reacts with SARS Patient Serum

    Directory of Open Access Journals (Sweden)

    K.-Y. Hwa

    2008-01-01

    Full Text Available Molecular mimicry, defined as similar structures shared by molecules from dissimilar genes or proteins, is a general strategy used by pathogens to infect host cells. Severe acute respiratory syndrome (SARS is a new human respiratory infectious disease caused by SARS coronavirus (SARS-CoV. The spike (S protein of SARS-CoV plays an important role in the virus entry into a cell. In this study, eleven synthetic peptides from the S protein were selected based on its sequence homology with human proteins. Two of the peptides D07 (residues 927–937 and D08 (residues 942–951 were recognized by the sera of SARS patients. Murine hyperimmune sera against these peptides bound to proteins of human lung epithelial cells A549. Another peptide D10 (residues 490–502 stimulated A549 to proliferate and secrete IL-8. The present results suggest that the selected S protein regions, which share sequence homology with human proteins, may play important roles in SARS-CoV infection.

  5. Efficient prediction of human protein-protein interactions at a global scale.

    Science.gov (United States)

    Schoenrock, Andrew; Samanfar, Bahram; Pitre, Sylvain; Hooshyar, Mohsen; Jin, Ke; Phillips, Charles A; Wang, Hui; Phanse, Sadhna; Omidi, Katayoun; Gui, Yuan; Alamgir, Md; Wong, Alex; Barrenäs, Fredrik; Babu, Mohan; Benson, Mikael; Langston, Michael A; Green, James R; Dehne, Frank; Golshani, Ashkan

    2014-12-10

    Our knowledge of global protein-protein interaction (PPI) networks in complex organisms such as humans is hindered by technical limitations of current methods. On the basis of short co-occurring polypeptide regions, we developed a tool called MP-PIPE capable of predicting a global human PPI network within 3 months. With a recall of 23% at a precision of 82.1%, we predicted 172,132 putative PPIs. We demonstrate the usefulness of these predictions through a range of experiments. The speed and accuracy associated with MP-PIPE can make this a potential tool to study individual human PPI networks (from genomic sequences alone) for personalized medicine.

  6. Induced proteins in human melanomas by γ-ray

    International Nuclear Information System (INIS)

    Ohnishi, T.; Ihara, M.; Utsumi, H.

    1992-01-01

    When cells are exposed to environmental stresses such as heat, chemicals, radiation, the cells respond to them by synthesizing a characteristic group of proteins, called stress proteins. There are many famous stress proteins: heat shock proteins and metallothionein. Treated cells have a protective mechanism against these environmental stresses. SOS responses in Escherichia coli are most famous. As the mechanisms, when cells are exposed by many kinds of DNA damage agents, various enzymes are induced after the cleavage of repressor protein LexA by activated RecA enzyme. Thereafter, induced proteins act for DNA repair and mutagenesis. In mammalian cells there are many reports about inducible genes such as O 6 -methylguanine methyltransferase gene. This gene was also inducible by alkylating agents. The difference of radiation sensitivities may be reflected by the contents of repair enzymes(s) or the induced proteins. Therefore, this study aims on the differences in inducible proteins between radiosensitive cells and control cells. Since it was hypothesized that induced proteins concerning to DNA damage repair or the proteins to recognize the damage may exist in the nuclei, induced proteins in nuclei of γ-ray irradiated cells were analyzed. (author). 5 refs., 1 tab

  7. Are animal models predictive for human postmortem muscle protein degradation?

    Science.gov (United States)

    Ehrenfellner, Bianca; Zissler, Angela; Steinbacher, Peter; Monticelli, Fabio C; Pittner, Stefan

    2017-11-01

    A most precise determination of the postmortem interval (PMI) is a crucial aspect in forensic casework. Although there are diverse approaches available to date, the high heterogeneity of cases together with the respective postmortal changes often limit the validity and sufficiency of many methods. Recently, a novel approach for time since death estimation by the analysis of postmortal changes of muscle proteins was proposed. It is however necessary to improve the reliability and accuracy, especially by analysis of possible influencing factors on protein degradation. This is ideally investigated on standardized animal models that, however, require legitimization by a comparison of human and animal tissue, and in this specific case of protein degradation profiles. Only if protein degradation events occur in comparable fashion within different species, respective findings can sufficiently be transferred from the animal model to application in humans. Therefor samples from two frequently used animal models (mouse and pig), as well as forensic cases with representative protein profiles of highly differing PMIs were analyzed. Despite physical and physiological differences between species, western blot analysis revealed similar patterns in most of the investigated proteins. Even most degradation events occurred in comparable fashion. In some other aspects, however, human and animal profiles depicted distinct differences. The results of this experimental series clearly indicate the huge importance of comparative studies, whenever animal models are considered. Although animal models could be shown to reflect the basic principles of protein degradation processes in humans, we also gained insight in the difficulties and limitations of the applicability of the developed methodology in different mammalian species regarding protein specificity and methodic functionality.

  8. Protein and Amino Acid Restriction, Aging and Disease: from yeast to humans

    OpenAIRE

    Mirzaei, Hamed; Suarez, Jorge A.; Longo, Valter D.

    2014-01-01

    Many of the effects of dietary restriction (DR) on longevity and health span in model organisms have been linked to reduced protein and amino acid (AA) intake and the stimulation of specific nutrient signaling pathways. Studies in yeast have shown that addition of serine, threonine, and valine in media promotes cellular sensitization and aging by activating different but connected pathways. Protein or essential AA restriction extends both lifespan and healthspan in rodent models. In humans, p...

  9. Structural studies of human glioma pathogenesis-related protein 1

    Energy Technology Data Exchange (ETDEWEB)

    Asojo, Oluwatoyin A., E-mail: oasojo@unmc.edu [College of Medicine, Nebraska Medical Center, Omaha, NE 68198-6495 (United States); Koski, Raymond A.; Bonafé, Nathalie [L2 Diagnostics LLC, 300 George Street, New Haven, CT 06511 (United States); College of Medicine, Nebraska Medical Center, Omaha, NE 68198-6495 (United States)

    2011-10-01

    Structural analysis of a truncated soluble domain of human glioma pathogenesis-related protein 1, a membrane protein implicated in the proliferation of aggressive brain cancer, is presented. Human glioma pathogenesis-related protein 1 (GLIPR1) is a membrane protein that is highly upregulated in brain cancers but is barely detectable in normal brain tissue. GLIPR1 is composed of a signal peptide that directs its secretion, a conserved cysteine-rich CAP (cysteine-rich secretory proteins, antigen 5 and pathogenesis-related 1 proteins) domain and a transmembrane domain. GLIPR1 is currently being investigated as a candidate for prostate cancer gene therapy and for glioblastoma targeted therapy. Crystal structures of a truncated soluble domain of the human GLIPR1 protein (sGLIPR1) solved by molecular replacement using a truncated polyalanine search model of the CAP domain of stecrisp, a snake-venom cysteine-rich secretory protein (CRISP), are presented. The correct molecular-replacement solution could only be obtained by removing all loops from the search model. The native structure was refined to 1.85 Å resolution and that of a Zn{sup 2+} complex was refined to 2.2 Å resolution. The latter structure revealed that the putative binding cavity coordinates Zn{sup 2+} similarly to snake-venom CRISPs, which are involved in Zn{sup 2+}-dependent mechanisms of inflammatory modulation. Both sGLIPR1 structures have extensive flexible loop/turn regions and unique charge distributions that were not observed in any of the previously reported CAP protein structures. A model is also proposed for the structure of full-length membrane-bound GLIPR1.

  10. Calcium-binding proteins from human platelets

    International Nuclear Information System (INIS)

    Gogstad, G.O.; Krutnes, M.B.; Solum, N.O.

    1983-01-01

    Calcium-binding platelet proteins were examined by crossed immunoelectrophoresis of solubilized platelets against antibodies to whole platelets followed by incubation of the immunoplates with 45 Ca 2 + and autoradiography. When the immunoplates had been pretreated with EDTA at pH 9.0 in order to remove divalent cations, three immunoprecipitates were markedly labelled with 45 Ca 2 + . These corresponded to the glycoprotein IIb-IIIa complex, glycoprotein Ia and a presently unidentified antigen termed G18. These antigens were membrane-bound and surface-oriented. When an excess of EDTA was introduced in the incubation media the results revealed that the glycoprotein IIb-IIIa complex and antigen G18, but not glycoprotein Ia, contained sites with a stronger affinity for calcium than has EDTA at pH 7.4 Immunoprecipitates of the separate glycoproteins IIb and IIIa both bound calcium in the same manner as the glycoprotein IIb-IIIa complex. As another approach, platelet-rich plasma was incubated with 45 Ca 2 + prior to crossed immunoelectrophoresis of the solubilized platelets. A single immunoprecipitate was wekly labelled. This did not correspond to any of the immunoprecipitates which were visible after staining with Coomassie blue. The labelling of this antigen was markedly increased when the platelt-rich plasma had been preincubated with EDTA and in this case a weak labelling of the glycoprotein IIB-IIIa precipitate also became apparent. No increased incorporation of calcium occured in any of these immunoprecipitates when the platelets were aggregated with ADP in the presence of 45 Ca 2 + . (orig.)

  11. Evidence for radical-oxidation of plasma proteins in humans

    International Nuclear Information System (INIS)

    Wang, D.; Davies, M.; Dean, R.; Fu, S.; Taurins, A.; Sullivans, D.

    1998-01-01

    Oxidation of proteins by radicals has been implicated in many pathological processes. The hydroxyl radical is known to generate protein-bound hydroxylated derivatives of amino acids, for example hydroxyvaline (from Val), hydroxyleucine (from Leu), o-tyrosine (from Phe), and DOPA (from Tyr). In this study, we have investigated the occurrence of these oxidised amino acids in human plasma proteins from both normal subjects and dialysis patients. By employing previously established HPLC methods [Fu et al. Biochemical Journal, 330, 233-239, 1998], we have found that oxidised amino acids exist in normal human plasma proteins (n=32). The level of these oxidised amino acids is not correlated to age. Similar levels of oxidised amino acids are found in the plasma proteins of the dialysis patients (n=6), but a more detailed survey is underway. The relative abundance of the oxidised amino acids is similar to that resulting from oxidation of BSA by hydroxy radicals or Fenton systems [Fu et al. Biochemical Journal, 333, 519-525, 1998]. The results suggest that metal-ion catalysed oxyl-radical chemistry may be a key contributor to the oxidative damage in plasma proteins in vivo in humans

  12. Constitutive phosphorylation of Shc proteins in human tumors

    DEFF Research Database (Denmark)

    Pelicci, G; Lanfrancone, L; Salcini, A E

    1995-01-01

    The Shc gene encodes three overlapping proteins which all contain a carboxy-terminal SH2 domain. Shc proteins are ubiquitously expressed and are downstream targets and effectors of activated tyrosine kinases (TK). We investigated tyrosine-phosphorylation of Shc proteins in normal and transformed...... of the Shc-associated phosphoproteins (EGFR, PDGFR, erbB-2, Met, bcr-abl, H4-ret) bound both the Shc- and Grb2-SH2 domains in vitro; others (p175; p70-p80) only the Shc-SH2 domain and yet others (p140) only the Grb2-SH3 domains. These results indicate that Shc proteins are common substrates of constitutively...

  13. Brain Activity and Human Unilateral Chewing

    Science.gov (United States)

    Quintero, A.; Ichesco, E.; Myers, C.; Schutt, R.; Gerstner, G.E.

    2012-01-01

    Brain mechanisms underlying mastication have been studied in non-human mammals but less so in humans. We used functional magnetic resonance imaging (fMRI) to evaluate brain activity in humans during gum chewing. Chewing was associated with activations in the cerebellum, motor cortex and caudate, cingulate, and brainstem. We also divided the 25-second chew-blocks into 5 segments of equal 5-second durations and evaluated activations within and between each of the 5 segments. This analysis revealed activation clusters unique to the initial segment, which may indicate brain regions involved with initiating chewing. Several clusters were uniquely activated during the last segment as well, which may represent brain regions involved with anticipatory or motor events associated with the end of the chew-block. In conclusion, this study provided evidence for specific brain areas associated with chewing in humans and demonstrated that brain activation patterns may dynamically change over the course of chewing sequences. PMID:23103631

  14. Human muscle proteins: analysis by two-dimensional electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Giometti, C.S.; Danon, M.J.; Anderson, N.G.

    1983-09-01

    Proteins from single frozen sections of human muscle were separated by two-dimensional gel electrophoresis and detected by fluorography or Coomassie Blue staining. The major proteins were identical in different normal muscles obtained from either sex at different ages, and in Duchenne and myotonic dystrophy samples. Congenital myopathy denervation atrophy, polymyositis, and Becker's muscular dystrophy samples, however, showed abnormal myosin light chain compositions, some with a decrease of fast-fiber myosin light chains and others with a decrease of slow-fiber light chains. These protein alterations did not correlate with any specific disease, and may be cause by generalized muscle-fiber damage.

  15. Proteomic data from human cell cultures refine mechanisms of chaperone-mediated protein homeostasis.

    Science.gov (United States)

    Finka, Andrija; Goloubinoff, Pierre

    2013-09-01

    In the crowded environment of human cells, folding of nascent polypeptides and refolding of stress-unfolded proteins is error prone. Accumulation of cytotoxic misfolded and aggregated species may cause cell death, tissue loss, degenerative conformational diseases, and aging. Nevertheless, young cells effectively express a network of molecular chaperones and folding enzymes, termed here "the chaperome," which can prevent formation of potentially harmful misfolded protein conformers and use the energy of adenosine triphosphate (ATP) to rehabilitate already formed toxic aggregates into native functional proteins. In an attempt to extend knowledge of chaperome mechanisms in cellular proteostasis, we performed a meta-analysis of human chaperome using high-throughput proteomic data from 11 immortalized human cell lines. Chaperome polypeptides were about 10% of total protein mass of human cells, half of which were Hsp90s and Hsp70s. Knowledge of cellular concentrations and ratios among chaperome polypeptides provided a novel basis to understand mechanisms by which the Hsp60, Hsp70, Hsp90, and small heat shock proteins (HSPs), in collaboration with cochaperones and folding enzymes, assist de novo protein folding, import polypeptides into organelles, unfold stress-destabilized toxic conformers, and control the conformal activity of native proteins in the crowded environment of the cell. Proteomic data also provided means to distinguish between stable components of chaperone core machineries and dynamic regulatory cochaperones.

  16. Carboxypeptidase activity in human mycoplasmas.

    OpenAIRE

    Shibata, K; Watanabe, T

    1986-01-01

    Mycoplasma salivarium produced citrulline, ammonia, and ATP from N-benzoylglycyl-L-arginine. The activity was inhibited by EDTA and was therefore concluded to be due to an arginine-specific carboxypeptidase. The activity was also found to exist in M. orale, M. buccale, M. faucium, and M. hominis.

  17. A human-specific de novo protein-coding gene associated with human brain functions.

    Directory of Open Access Journals (Sweden)

    Chuan-Yun Li

    2010-03-01

    Full Text Available To understand whether any human-specific new genes may be associated with human brain functions, we computationally screened the genetic vulnerable factors identified through Genome-Wide Association Studies and linkage analyses of nicotine addiction and found one human-specific de novo protein-coding gene, FLJ33706 (alternative gene symbol C20orf203. Cross-species analysis revealed interesting evolutionary paths of how this gene had originated from noncoding DNA sequences: insertion of repeat elements especially Alu contributed to the formation of the first coding exon and six standard splice junctions on the branch leading to humans and chimpanzees, and two subsequent substitutions in the human lineage escaped two stop codons and created an open reading frame of 194 amino acids. We experimentally verified FLJ33706's mRNA and protein expression in the brain. Real-Time PCR in multiple tissues demonstrated that FLJ33706 was most abundantly expressed in brain. Human polymorphism data suggested that FLJ33706 encodes a protein under purifying selection. A specifically designed antibody detected its protein expression across human cortex, cerebellum and midbrain. Immunohistochemistry study in normal human brain cortex revealed the localization of FLJ33706 protein in neurons. Elevated expressions of FLJ33706 were detected in Alzheimer's brain samples, suggesting the role of this novel gene in human-specific pathogenesis of Alzheimer's disease. FLJ33706 provided the strongest evidence so far that human-specific de novo genes can have protein-coding potential and differential protein expression, and be involved in human brain functions.

  18. Human amyloid beta protein gene locus: HaeIII RFLP

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, J E; Gonzalez-DeWhitt, P A; Fuller, F; Cordell, B; Frossard, P M [California Biotechnology Inc., Mountain View (USA); Tinklenberg, J R; Davies, H D; Eng, L F; Yesavage, J A [Stanford Univ. School of Medicine, Palo Alto, CA (USA)

    1988-07-25

    A 2.2 kb EcoRI-EcoRI fragment from the 5{prime} end of the human amyloid beta protein cDNA was isolated from a human fibroblast cDNA library and subcloned into pGEM3. HaeIII (GGCC) detects 6 invariant bands at 0.5 kb, 1.0 kb, 1.1 kb, 1.3 kb, 1.4 kb and 1.6 kb and a two-allele polymorphism with bands at either 1.9 kb or 2.1 kb. Its frequency was studied in 50 North Americans. Human amyloid beta protein gene mapped to the long arm of chromosome 21 (21q11.2-21q21) by Southern blot analysis of human-rodent somatic cell hybrids. Co-dominant segregation was observed in two families (15 individuals).

  19. Competitive Protein Adsorption of Albumin and Immunoglobulin G from Human Serum onto Polymer Surfaces

    DEFF Research Database (Denmark)

    Holmberg, Maria; Hou, Xiaolin

    2010-01-01

    protein adsorption from diluted human serum solutions with relatively low protein concentrations, but the nonfouling character was weakened when less diluted human serum solutions with higher protein concentrations were used. The observed adsorption trend is independent of adsorption time, indicating...

  20. A two-site immunoradiometric assay for human pregnancy-associated plasma protein A (PAPP-A) using monoclonal antibodies

    International Nuclear Information System (INIS)

    Mowles, E.A.; Pinto-Furtado, L.G.; Bolton, A.E.

    1986-01-01

    A rapid, sensitive immunoradiometric assay has been developed for human pregnancy-associated plasma protein A (PAPP-A) using a purified mouse monoclonal antibody as the tracer and a rabbit polyclonal antibody to this protein in the solid-phase antibody preparation. The assay showed no measurable cross-reaction (< 0.1%) against a range of purified human placental proteins, and a good correlation with a previously described radioimmunoassay procedure when tested on samples taken throughout normal human pregnancies. No PAPP-A-like immunological activity could be detected in sera from non-pregnant women, confirming the absence of this protein from the circulation outside pregnancy. (Auth.)

  1. Sulfated glycopeptide nanostructures for multipotent protein activation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sungsoo S.; Fyrner, Timmy; Chen, Feng; Álvarez, Zaida; Sleep, Eduard; Chun, Danielle S.; Weiner, Joseph A.; Cook, Ralph W.; Freshman, Ryan D.; Schallmo, Michael S.; Katchko, Karina M.; Schneider, Andrew D.; Smith, Justin T.; Yun, Chawon; Singh, Gurmit; Hashmi, Sohaib Z.; McClendon, Mark T.; Yu, Zhilin; Stock, Stuart R.; Hsu, Wellington K.; Hsu, Erin L.; Stupp , Samuel I. (NWU)

    2017-06-19

    Biological systems have evolved to utilize numerous proteins with capacity to bind polysaccharides for the purpose of optimizing their function. A well-known subset of these proteins with binding domains for the highly diverse sulfated polysaccharides are important growth factors involved in biological development and tissue repair. We report here on supramolecular sulfated glycopeptide nanostructures, which display a trisulfated monosaccharide on their surfaces and bind five critical proteins with different polysaccharide-binding domains. Binding does not disrupt the filamentous shape of the nanostructures or their internal β-sheet backbone, but must involve accessible adaptive configurations to interact with such different proteins. The glycopeptide nanostructures amplified signalling of bone morphogenetic protein 2 significantly more than the natural sulfated polysaccharide heparin, and promoted regeneration of bone in the spine with a protein dose that is 100-fold lower than that required in the animal model. These highly bioactive nanostructures may enable many therapies in the future involving proteins.

  2. Expression of sterol regulatory element-binding transcription factor (SREBF 2 and SREBF cleavage-activating protein (SCAP in human atheroma and the association of their allelic variants with sudden cardiac death

    Directory of Open Access Journals (Sweden)

    Kytömäki Leena

    2008-12-01

    Full Text Available Abstract Background Disturbed cellular cholesterol homeostasis may lead to accumulation of cholesterol in human atheroma plaques. Cellular cholesterol homeostasis is controlled by the sterol regulatory element-binding transcription factor 2 (SREBF-2 and the SREBF cleavage-activating protein (SCAP. We investigated whole genome expression in a series of human atherosclerotic samples from different vascular territories and studied whether the non-synonymous coding variants in the interacting domains of two genes, SREBF-2 1784G>C (rs2228314 and SCAP 2386A>G, are related to the progression of coronary atherosclerosis and the risk of pre-hospital sudden cardiac death (SCD. Methods Whole genome expression profiling was completed in twenty vascular samples from carotid, aortic and femoral atherosclerotic plaques and six control samples from internal mammary arteries. Three hundred sudden pre-hospital deaths of middle-aged (33–69 years Caucasian Finnish men were subjected to detailed autopsy in the Helsinki Sudden Death Study. Coronary narrowing and areas of coronary wall covered with fatty streaks or fibrotic, calcified or complicated lesions were measured and related to the SREBF-2 and SCAP genotypes. Results Whole genome expression profiling showed a significant (p = 0.02 down-regulation of SREBF-2 in atherosclerotic carotid plaques (types IV-V, but not in the aorta or femoral arteries (p = NS for both, as compared with the histologically confirmed non-atherosclerotic tissues. In logistic regression analysis, a significant interaction between the SREBF-2 1784G>C and the SCAP 2386A>G genotype was observed on the risk of SCD (p = 0.046. Men with the SREBF-2 C allele and the SCAP G allele had a significantly increased risk of SCD (OR 2.68, 95% CI 1.07–6.71, compared to SCAP AA homologous subjects carrying the SREBF-2 C allele. Furthermore, similar trends for having complicated lesions and for the occurrence of thrombosis were found, although the

  3. Synergistic inhibition of the intrinsic factor X activation by protein S and C4b-binding protein

    NARCIS (Netherlands)

    Koppelman, S.J.

    1995-01-01

    The complement protein C4b-binding protein plays an important role in the regulation of the protein C anticoagulant pathway. C4b-binding protein can bind to protein S, thereby inhibiting the cofactor activity of protein S for activated protein C. In this report, we describe a new role for

  4. Characterization of the human GARP (Golgi associated retrograde protein) complex

    International Nuclear Information System (INIS)

    Liewen, Heike; Meinhold-Heerlein, Ivo; Oliveira, Vasco; Schwarzenbacher, Robert; Luo Guorong; Wadle, Andreas; Jung, Martin; Pfreundschuh, Michael; Stenner-Liewen, Frank

    2005-01-01

    The Golgi associated retrograde protein complex (GARP) or Vps fifty-three (VFT) complex is part of cellular inter-compartmental transport systems. Here we report the identification of the VFT tethering factor complex and its interactions in mammalian cells. Subcellular fractionation shows that human Vps proteins are found in the smooth membrane/Golgi fraction but not in the cytosol. Immunostaining of human Vps proteins displays a vesicular distribution most concentrated at the perinuclear envelope. Co-staining experiments with endosomal markers imply an endosomal origin of these vesicles. Significant accumulation of VFT complex positive endosomes is found in the vicinity of the Trans Golgi Network area. This is in accordance with a putative role in Golgi associated transport processes. In Saccharomyces cerevisiae, GARP is the main effector of the small GTPase Ypt6p and interacts with the SNARE Tlg1p to facilitate membrane fusion. Accordingly, the human homologue of Ypt6p, Rab6, specifically binds hVps52. In human cells, the 'orphan' SNARE Syntaxin 10 is the genuine binding partner of GARP mediated by hVps52. This reveals a previously unknown function of human Syntaxin 10 in membrane docking and fusion events at the Golgi. Taken together, GARP shows significant conservation between various species but diversification and specialization result in important differences in human cells

  5. Protein chimerism: novel source of protein diversity in humans adds complexity to bottom-up proteomics.

    Science.gov (United States)

    Casado-Vela, Juan; Lacal, Juan Carlos; Elortza, Felix

    2013-01-01

    Three main molecular mechanisms are considered to contribute expanding the repertoire and diversity of proteins present in living organisms: first, at DNA level (gene polymorphisms and single nucleotide polymorphisms); second, at messenger RNA (pre-mRNA and mRNA) level including alternative splicing (also termed differential splicing or cis-splicing); finally, at the protein level mainly driven through PTM and specific proteolytic cleavages. Chimeric mRNAs constitute an alternative source of protein diversity, which can be generated either by chromosomal translocations or by trans-splicing events. The occurrence of chimeric mRNAs and proteins is a frequent event in cells from the immune system and cancer cells, mainly as a consequence of gene rearrangements. Recent reports support that chimeric proteins may also be expressed at low levels under normal physiological circumstances, thus, representing a novel source of protein diversity. Notably, recent publications demonstrate that chimeric protein products can be successfully identified through bottom-up proteomic analyses. Several questions remain unsolved, such as the physiological role and impact of such chimeric proteins or the potential occurrence of chimeric proteins in higher eukaryotic organisms different from humans. The occurrence of chimeric proteins certainly seems to be another unforeseen source of complexity for the proteome. It may be a process to take in mind not only when performing bottom-up proteomic analyses in cancer studies but also in general bottom-up proteomics experiments. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. The interaction of protein S with the phospholipid surface is essential for the activated protein C-independent activity of protein S

    NARCIS (Netherlands)

    van Wijnen, M.; Stam, J. G.; van't Veer, C.; Meijers, J. C.; Reitsma, P. H.; Bertina, R. M.; Bouma, B. N.

    1996-01-01

    Protein S is a vitamin-K dependent glycoprotein involved in the regulation of the anticoagulant activity of activated protein C (APC). Recent data showed a direct anticoagulant role of protein S independent of APC, as demonstrated by the inhibition of prothrombinase and tenase activity both in

  7. Human TFDP3, a novel DP protein, inhibits DNA binding and transactivation by E2F

    DEFF Research Database (Denmark)

    Qiao, Huan; Di Stefano, Luisa; Tian, Chan

    2006-01-01

    The two known DP proteins, TFDP1 and -2, bind E2Fs to form heterodimers essential for high affinity DNA binding and efficient transcriptional activation/repression. Here we report the identification of a new member of the DP family, human TFDP3. Despite the high degree of sequence similarity, TFD...

  8. Human recombinant protein C for severe sepsis and septic shock in adult and paediatric patients

    DEFF Research Database (Denmark)

    Martí-Carvajal, Arturo J; Solà, Ivan; Gluud, Christian

    2012-01-01

    Sepsis is a common and frequently fatal condition. Human recombinant activated protein C (APC) has been introduced to reduce the high risk of death associated with severe sepsis or septic shock. This systematic review is an update of a Cochrane review originally published in 2007....

  9. Induction of Heat Shock Protein Expression in Cervical Epithelial Cells by Human Semen

    Directory of Open Access Journals (Sweden)

    J. C. Jeremias

    1999-01-01

    Full Text Available Objective: The 70kD heat shock protein (Hsp70, induced when cells are subjected to environmental stress, prevents the denaturation and incorrect folding of polypeptides and may expedite replication and transmission of DNA and RNA viruses. We analyzed whether messenger RNA (mRNA for Hsp70 was expressed following exposure of a cultured human cervical cell line (HeLa cells to human semen or in cervical cells from sexually active women.

  10. Optimizing the measurement of mitochondrial protein synthesis in human skeletal muscle.

    Science.gov (United States)

    Burd, Nicholas A; Tardif, Nicolas; Rooyackers, Olav; van Loon, Luc J C

    2015-01-01

    The measurement of mitochondrial protein synthesis after food ingestion, contractile activity, and/or disease is often used to provide insight into skeletal muscle adaptations that occur in the longer term. Studies have shown that protein ingestion stimulates mitochondrial protein synthesis in human skeletal muscle. Minor differences in the stimulation of mitochondrial protein synthesis occur after a single bout of resistance or endurance exercise. There appear to be no measurable differences in mitochondrial protein synthesis between critically ill patients and aged-matched controls. However, the mitochondrial protein synthetic response is reduced at a more advanced age. In this paper, we discuss the challenges involved in the measurement of human skeletal muscle mitochondrial protein synthesis rates based on stable isotope amino acid tracer methods. Practical guidelines are discussed to improve the reliability of the measurement of mitochondrial protein synthesis rates. The value of the measurement of mitochondrial protein synthesis after a single meal or exercise bout on the prediction of the longer term skeletal muscle mass and performance outcomes in both the healthy and disease populations requires more work, but we emphasize that the measurements need to be reliable to be of any value to the field.

  11. Sensing Human Activity: GPS Tracking

    Science.gov (United States)

    van der Spek, Stefan; van Schaick, Jeroen; de Bois, Peter; de Haan, Remco

    2009-01-01

    The enhancement of GPS technology enables the use of GPS devices not only as navigation and orientation tools, but also as instruments used to capture travelled routes: as sensors that measure activity on a city scale or the regional scale. TU Delft developed a process and database architecture for collecting data on pedestrian movement in three European city centres, Norwich, Rouen and Koblenz, and in another experiment for collecting activity data of 13 families in Almere (The Netherlands) for one week. The question posed in this paper is: what is the value of GPS as ‘sensor technology’ measuring activities of people? The conclusion is that GPS offers a widely useable instrument to collect invaluable spatial-temporal data on different scales and in different settings adding new layers of knowledge to urban studies, but the use of GPS-technology and deployment of GPS-devices still offers significant challenges for future research. PMID:22574061

  12. Sensing Human Activity: GPS Tracking

    Directory of Open Access Journals (Sweden)

    Remco de Haan

    2009-04-01

    Full Text Available The enhancement of GPS technology enables the use of GPS devices not only as navigation and orientation tools, but also as instruments used to capture travelled routes: as sensors that measure activity on a city scale or the regional scale. TU Delft developed a process and database architecture for collecting data on pedestrian movement in three European city centres, Norwich, Rouen and Koblenz, and in another experiment for collecting activity data of 13 families in Almere (The Netherlands for one week. The question posed in this paper is: what is the value of GPS as ‘sensor technology’ measuring activities of people? The conclusion is that GPS offers a widely useable instrument to collect invaluable spatial-temporal data on different scales and in different settings adding new layers of knowledge to urban studies, but the use of GPS-technology and deployment of GPS-devices still offers significant challenges for future research.

  13. Sulfur in human nutrition - effects beyond protein synthesis

    NARCIS (Netherlands)

    Gertjan Schaafsma

    2008-01-01

    That sulfur is essential to humans is based on the requirement of S-animo acids for normal growth and maintenance of nitrogen balance and not on the optimization of metabolic proccesses involving the synthesis of non-protein sulphur containing compounds. This paper reviews the significance of sulfur

  14. C- Reactive Protein in Tuberculosis and Human Immunodeficiency ...

    African Journals Online (AJOL)

    This study was conducted to evaluate C-reactive protein (CRP) levels in Mycobacterium tuberculosis and human immunodeficiency virus (HIV) infections and the follow-up therapeutic response to tuberculosis (TB) among patients aged 19-68 years attending out-patient clinics of two hospitals in Abeokuta, Southwestern ...

  15. Proteomic analysis of heparin-binding proteins from human seminal ...

    Indian Academy of Sciences (India)

    Prakash

    (MALDI TOF/MS) for protein analysis of human HBPs. We resolved 70 ... Thus, the combined effects of seminal plasma components support the survival of ...... The BBXB motif of RANTES is the principal site for heparin binding and controls ...

  16. Efficacy of antipsychotic agents at human 5-HT(1A) receptors determined by [3H]WAY100,635 binding affinity ratios: relationship to efficacy for G-protein activation.

    Science.gov (United States)

    Newman-Tancredi, A; Verrièle, L; Touzard, M; Millan, M J

    2001-10-05

    5-HT(1A) receptors are implicated in the aetiology of schizophrenia. Herein, the influence of 15 antipsychotics on the binding of the selective 'neutral' antagonist, [3H]WAY100,635 ([3H]N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl)-cyclo-hexanecarboxamide), was examined at human 5-HT(1A) receptors expressed in Chinese Hamster Ovary cells. In competition binding experiments, 5-HT displayed biphasic isotherms which were shifted to the right in the presence of the G-protein uncoupling agent, GTPgammaS (100 microM). In analogy, the isotherms of ziprasidone, quetiapine and S16924 (((R-2-[1-[2-(2,3-dihydro-benzo[1,4]dioxin-5-yloxy)-ethyl]-pyrrolidin-3yl]-1-(4-fluoro-phenyl)-ethanone), were displaced to the right by GTPgammaS, consistent with agonist actions. Binding of several other antipsychotics, such as ocaperidone, olanzapine and risperidone, was little influenced by GTPgammaS. Isotherms of the neuroleptics, haloperidol, chlorpromazine and thioridazine were shifted to the left in the presence of GTPgammaS, suggesting inverse agonist properties. For most ligands, the magnitude of affinity changes induced by GTPgammaS (alteration in pK(i) values) correlated well with their previously determined efficacies in [35S]GTPgammaS binding studies [Eur. J. Pharmacol. 355 (1998) 245]. In contrast, the affinity of the 'atypical' antipsychotic agent, clozapine, which is a known partial agonist at 5-HT(1A) receptors, was less influenced by GTPgammaS. When the ratio of high-/low-affinity values was plotted against efficacy, hyperbolic isotherms were obtained, consistent with a modified ternary complex model which assumes that receptors can adopt active conformations in the absence of agonist. In conclusion, modulation of [3H]-WAY100,635 binding by GTPgammaS differentiated agonist vs. inverse agonist properties of antipsychotics at 5-HT(1A) receptors. These may contribute to differing profiles of antipsychotic activity.

  17. EXPRESSION AND SIGNIFICANCE OF ERK PROTEIN IN HUMAN BREAST CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    张秀梅; 李柏林; 宋敏; 宋继谒

    2004-01-01

    Objective: To investigate the expression of ERK and p-ERK protein in human breast cancer and their corresponding tissue, to assess the significance of ERK signal pathway in tumorigenesis and progression of breast carcinoma. Methods: 40 breast cancer cases were used in S-P immunohistochemistry technique and Western Blot study. Results: The expression of ERK1, ERK2, and p- ERK protein levels increased remarkably in breast cancer tissues in comparison to normal tissues (P<0.01). The expression was upregulated by 1.32-, 1.53-and 4.27-fold, respectively. The overexpressions of ERK1, ERK2, and p- ERK proteins were obviously correlated with clinical stage of breast cancer. Protein levels of ERK and p-ERK were higher in stage III patients than in stage I and stage II patients (P<0.05). These proteins were strongly related with axillary lymph node metastasis of breast cancer, but not correlated with histopathological type and status of ER and PR of breast cancer. Expression of ERK1, and ERK2, protein showed a positive linear correlation. Conclusion: ERK signal transduction pathway is a key factor during human breast tumorigenesis and breast cancer progression.

  18. Activation of peroxisome proliferator-activated receptor-α enhances fatty acid oxidation in human adipocytes

    International Nuclear Information System (INIS)

    Lee, Joo-Young; Hashizaki, Hikari; Goto, Tsuyoshi; Sakamoto, Tomoya; Takahashi, Nobuyuki; Kawada, Teruo

    2011-01-01

    Highlights: → PPARα activation increased mRNA expression levels of adipocyte differentiation marker genes and GPDH activity in human adipocytes. → PPARα activation also increased insulin-dependent glucose uptake in human adipocytes. → PPARα activation did not affect lipid accumulation in human adipocytes. → PPARα activation increased fatty acid oxidation through induction of fatty acid oxidation-related genes in human adipocytes. -- Abstract: Peroxisome proliferator-activated receptor-α (PPARα) is a key regulator for maintaining whole-body energy balance. However, the physiological functions of PPARα in adipocytes have been unclarified. We examined the functions of PPARα using human multipotent adipose tissue-derived stem cells as a human adipocyte model. Activation of PPARα by GW7647, a potent PPARα agonist, increased the mRNA expression levels of adipocyte differentiation marker genes such as PPARγ, adipocyte-specific fatty acid-binding protein, and lipoprotein lipase and increased both GPDH activity and insulin-dependent glucose uptake level. The findings indicate that PPARα activation stimulates adipocyte differentiation. However, lipid accumulation was not changed, which is usually observed when PPARγ is activated. On the other hand, PPARα activation by GW7647 treatment induced the mRNA expression of fatty acid oxidation-related genes such as CPT-1B and AOX in a PPARα-dependent manner. Moreover, PPARα activation increased the production of CO 2 and acid soluble metabolites, which are products of fatty acid oxidation, and increased oxygen consumption rate in human adipocytes. The data indicate that activation of PPARα stimulates both adipocyte differentiation and fatty acid oxidation in human adipocytes, suggesting that PPARα agonists could improve insulin resistance without lipid accumulation in adipocytes. The expected effects of PPARα activation are very valuable for managing diabetic conditions accompanied by obesity, because

  19. Prediction of the Ebola Virus Infection Related Human Genes Using Protein-Protein Interaction Network.

    Science.gov (United States)

    Cao, HuanHuan; Zhang, YuHang; Zhao, Jia; Zhu, Liucun; Wang, Yi; Li, JiaRui; Feng, Yuan-Ming; Zhang, Ning

    2017-01-01

    Ebola hemorrhagic fever (EHF) is caused by Ebola virus (EBOV). It is reported that human could be infected by EBOV with a high fatality rate. However, association factors between EBOV and host still tend to be ambiguous. According to the "guilt by association" (GBA) principle, proteins interacting with each other are very likely to function similarly or the same. Based on this assumption, we tried to obtain EBOV infection-related human genes in a protein-protein interaction network using Dijkstra algorithm. We hope it could contribute to the discovery of novel effective treatments. Finally, 15 genes were selected as potential EBOV infection-related human genes. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  20. ProNormz--an integrated approach for human proteins and protein kinases normalization.

    Science.gov (United States)

    Subramani, Suresh; Raja, Kalpana; Natarajan, Jeyakumar

    2014-02-01

    The task of recognizing and normalizing protein name mentions in biomedical literature is a challenging task and important for text mining applications such as protein-protein interactions, pathway reconstruction and many more. In this paper, we present ProNormz, an integrated approach for human proteins (HPs) tagging and normalization. In Homo sapiens, a greater number of biological processes are regulated by a large human gene family called protein kinases by post translational phosphorylation. Recognition and normalization of human protein kinases (HPKs) is considered to be important for the extraction of the underlying information on its regulatory mechanism from biomedical literature. ProNormz distinguishes HPKs from other HPs besides tagging and normalization. To our knowledge, ProNormz is the first normalization system available to distinguish HPKs from other HPs in addition to gene normalization task. ProNormz incorporates a specialized synonyms dictionary for human proteins and protein kinases, a set of 15 string matching rules and a disambiguation module to achieve the normalization. Experimental results on benchmark BioCreative II training and test datasets show that our integrated approach achieve a fairly good performance and outperforms more sophisticated semantic similarity and disambiguation systems presented in BioCreative II GN task. As a freely available web tool, ProNormz is useful to developers as extensible gene normalization implementation, to researchers as a standard for comparing their innovative techniques, and to biologists for normalization and categorization of HPs and HPKs mentions in biomedical literature. URL: http://www.biominingbu.org/pronormz. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Electrophoretic detection of protein p53 in human leukocytes

    International Nuclear Information System (INIS)

    Paponov, V.D.; Kupsik, E.G.; Shcheglova, E.G.; Yarullin, N.N.

    1986-01-01

    The authors have found an acid-soluble protein with mol. wt. of about 53 kD in peripheral blood leukocytes of persons with Down's syndrome. It was present in different quantities in all 20 patients tested, but was virtually not discovered in 12 healthy blood donors. This paper determines the possible identity of this protein with protein p53 from mouse ascites carcinoma by comparing their electrophoretic mobilities, because the accuracy of electrophoretic determination of the molecular weight of proteins is not sufficient to identify them. The paper also describes experiments to detect a protein with electrophoretic mobility identical with that of a protein in the leukocytes of patients with Down's syndrome in leukocytes of patients with leukemia. To discover if protein p53 is involved in cell proliferation, the protein composition of leukocytes from healthy blood donors, cultured in the presence and absence of phytohemagglutinin (PHA), was compared. Increased incorporation of H 3-thymidine by leukocytes of patients with Down's syndrome is explained by the presence of a population of immature leukocytes actively synthesizing DNA in the peripheral blood of these patients, and this can also explain the presence of protein p53 in the leukocytes of these patients

  2. Sensing human activity : GPS tracking

    NARCIS (Netherlands)

    van der Spek, Stefan; van Schaick, Jeroen; de Bois, P.G.; de Haan, Remco

    2009-01-01

    The enhancement of GPS technology enables the use of GPS devices not only as navigation and orientation tools, but also as instruments used to capture travelled routes: as sensors that measure activity on a city scale or the regional scale. TU Delft developed a process and database architecture for

  3. Unique expression of cytoskeletal proteins in human soft palate muscles.

    Science.gov (United States)

    Shah, Farhan; Berggren, Diana; Holmlund, Thorbjörn; Levring Jäghagen, Eva; Stål, Per

    2016-03-01

    The human oropharyngeal muscles have a unique anatomy with diverse and intricate functions. To investigate if this specialization is also reflected in the cytoarchitecture of muscle fibers, intermediate filament proteins and the dystrophin-associated protein complex have been analyzed in two human palate muscles, musculus uvula (UV) and musculus palatopharyngeus (PP), with immunohistochenmical and morphological techniques. Human limb muscles were used as reference. The findings show that the soft palate muscle fibers have a cytoskeletal architecture that differs from the limb muscles. While all limb muscles showed immunoreaction for a panel of antibodies directed against different domains of cytoskeletal proteins desmin and dystrophin, a subpopulation of palate muscle fibers lacked or had a faint immunoreaction for desmin (UV 11.7% and PP 9.8%) and the C-terminal of the dystrophin molecule (UV 4.2% and PP 6.4%). The vast majority of these fibers expressed slow contractile protein myosin heavy chain I. Furthermore, an unusual staining pattern was also observed in these fibers for β-dystroglycan, caveolin-3 and neuronal nitric oxide synthase nNOS, which are all membrane-linking proteins associated with the dystrophin C-terminus. While the immunoreaction for nNOS was generally weak or absent, β-dystroglycan and caveolin-3 showed a stronger immunostaining. The absence or a low expression of cytoskeletal proteins otherwise considered ubiquitous and important for integration and contraction of muscle cells indicate a unique cytoarchitecture designed to meet the intricate demands of the upper airway muscles. It can be concluded that a subgroup of muscle fibers in the human soft palate appears to have special biomechanical properties, and their unique cytoarchitecture must be taken into account while assessing function and pathology in oropharyngeal muscles. © 2015 Anatomical Society.

  4. SGLT2 Protein Expression Is Increased in Human Diabetic Nephropathy

    Science.gov (United States)

    Wang, Xiaoxin X.; Levi, Jonathan; Luo, Yuhuan; Myakala, Komuraiah; Herman-Edelstein, Michal; Qiu, Liru; Wang, Dong; Peng, Yingqiong; Grenz, Almut; Lucia, Scott; Dobrinskikh, Evgenia; D'Agati, Vivette D.; Koepsell, Hermann; Kopp, Jeffrey B.; Rosenberg, Avi Z.; Levi, Moshe

    2017-01-01

    There is very limited human renal sodium gradient-dependent glucose transporter protein (SGLT2) mRNA and protein expression data reported in the literature. The first aim of this study was to determine SGLT2 mRNA and protein levels in human and animal models of diabetic nephropathy. We have found that the expression of SGLT2 mRNA and protein is increased in renal biopsies from human subjects with diabetic nephropathy. This is in contrast to db-db mice that had no changes in renal SGLT2 protein expression. Furthermore, the effect of SGLT2 inhibition on renal lipid content and inflammation is not known. The second aim of this study was to determine the potential mechanisms of beneficial effects of SGLT2 inhibition in the progression of diabetic renal disease. We treated db/db mice with a selective SGLT2 inhibitor JNJ 39933673. We found that SGLT2 inhibition caused marked decreases in systolic blood pressure, kidney weight/body weight ratio, urinary albumin, and urinary thiobarbituric acid-reacting substances. SGLT2 inhibition prevented renal lipid accumulation via inhibition of carbohydrate-responsive element-binding protein-β, pyruvate kinase L, SCD-1, and DGAT1, key transcriptional factors and enzymes that mediate fatty acid and triglyceride synthesis. SGLT2 inhibition also prevented inflammation via inhibition of CD68 macrophage accumulation and expression of p65, TLR4, MCP-1, and osteopontin. These effects were associated with reduced mesangial expansion, accumulation of the extracellular matrix proteins fibronectin and type IV collagen, and loss of podocyte markers WT1 and synaptopodin, as determined by immunofluorescence microscopy. In summary, our study showed that SGLT2 inhibition modulates renal lipid metabolism and inflammation and prevents the development of nephropathy in db/db mice. PMID:28196866

  5. Heat shock proteins on the human sperm surface.

    Science.gov (United States)

    Naaby-Hansen, Soren; Herr, John C

    2010-01-01

    The sperm plasma membrane is known to be critical to fertilization and to be highly regionalized into domains of head, mid- and principal pieces. However, the molecular composition of the sperm plasma membrane and its alterations during genital tract passage, capacitation and the acrosome reaction remains to be fully dissected. A two-dimensional gel-based proteomic study previously identified 98 human sperm proteins which were accessible for surface labelling with both biotin and radioiodine. In this report twelve dually labelled protein spots were excised from stained gels or PDVF membranes and analysed by mass spectrometry (MS) and Edman degradation. Seven members from four different heat shock protein (HSP) families were identified including HYOU1 (ORP150), HSPC1 (HSP86), HSPA5 (Bip), HSPD1 (HSP60), and several isoforms of the two testis-specific HSP70 chaperones HSPA2 and HSPA1L. An antiserum raised against the testis-specific HSPA2 chaperone reacted with three 65kDa HSPA2 isoforms and three high molecular weight surface proteins (78-79kDa, 84kDa and 90-93kDa). These proteins, together with seven 65kDa HSP70 forms, reacted with human anti-sperm IgG antibodies that blocked in vitro fertilization in humans. Three of these surface biotinylated human sperm antigens were immunoprecipitated with a rabbit antiserum raised against a linear peptide epitope in Chlamydia trachomatis HSP70. The results indicate diverse HSP chaperones are accessible for surface labelling on human sperm. Some of these share epitopes with C. trachomatis HSP70, suggesting an association between genital tract infection, immunity to HSP70 and reproductive failure. 2009 Elsevier Ireland Ltd. All rights reserved.

  6. Human intestinal mucus proteins isolated by transanal irrigation and proctosigmoidoscopy

    Directory of Open Access Journals (Sweden)

    Paola Andrea Gómez Buitrago

    2014-10-01

    Full Text Available Human intestinal mucus essentially consists of a network of Mucin2 glycoproteins embedded in many lower molecular weight proteins. This paper contributes to the proteomic study of human intestinal mucus by comparing two sample collection methods (transanal irrigation and brush cytology during proctosigmoidoscopy and analysis techniques (electrophoresis and digestion in solution. The entire sample collection and treatment process is explained, including protein extraction, digestion and desalination and peptide characterisation using a nanoAcquity UPLC chromatograph coupled to an HDMS spectrometer equipped with a nanoESI source. Collecting mucus via transanal irrigation provided a larger sample volume and protein concentration from a single patient. The proctosigmoidoscopy sample could be analysed via digestion in solution after depleting albumin. The analysis indicates that a simple mucus lysis method can evaluate the electrophoresis and digestion in solution techniques. Studying human intestinal mucus complexes is important because they perform two essential survival functions for humans as the first biochemical and physical defences for the gastrointestinal tract and a habitat for intestinal microbiota, which are primarily hosted in the colon and exceeds the human genetic information and cell number 100- and 10-fold (1.

  7. The MCM-associated protein MCM-BP is important for human nuclear morphology.

    Science.gov (United States)

    Jagannathan, Madhav; Sakwe, Amos M; Nguyen, Tin; Frappier, Lori

    2012-01-01

    Mini-chromosome maintenance complex-binding protein (MCM-BP) was discovered as a protein that is strongly associated with human MCM proteins, known to be crucial for DNA replication in providing DNA helicase activity. The Xenopus MCM-BP homologue appears to play a role in unloading MCM complexes from chromatin after DNA synthesis; however, the importance of MCM-BP and its functional contribution to human cells has been unclear. Here we show that depletion of MCM-BP by sustained expression of short hairpin RNA (shRNA) results in highly abnormal nuclear morphology and centrosome amplification. The abnormal nuclear morphology was not seen with depletion of other MCM proteins and was rescued with shRNA-resistant MCM-BP. MCM-BP depletion was also found to result in transient activation of the G2 checkpoint, slowed progression through G2 and increased replication protein A foci, indicative of replication stress. In addition, MCM-BP depletion led to increased cellular levels of MCM proteins throughout the cell cycle including soluble MCM pools. The results suggest that MCM-BP makes multiple contributions to human cells that are not limited to unloading of the MCM complex.

  8. Conversion of human choriogonadotropin into a follitropin by protein engineering

    International Nuclear Information System (INIS)

    Campbell, R.K.; Dean-Emig, D.M.; Moyle, W.R.

    1991-01-01

    Human reproduction is dependent upon the action of follicle-stimulating hormone (hFSH), luteinizing hormone (hLH), and chorionic gonadotropin (hCG). While the α subunits of these heterodimeric proteins can be interchanged without effect on receptor-binding specificity, their β subunits differ and direct hormone binding to either LH/CG or FSH receptors. Previous studies employing chemical modifications of the hormones, monoclonal antibodies, or synthetic peptides have implicated hCG β-subunit residues between Cys-38 and Cys-57 and corresponding regions of hLHβ and hFSHβ in receptor recognition and activation. Since the β subunits of hCG or hLH and hFSH exhibit very little sequence similarity in this region, the authors postulated that these residues might contribute to hormone specificity. To test this hypothesis the authors constructed chimeric hCG/hFSH β subunits, coexpressed them with the human α subunit, and examined their ability to interact with LH and FSH receptors and hormone-specific monoclonal antibodies. Surprisingly, substitution of hFSHβ residues 33-52 for hCGβ residues 39-58 had no effect on receptor binding or stimulation. However, substitution of hFSHβ residues 88-108 in place of the carboxyl terminus of hCGβ (residues 94-145) resulted in a hormone analog identical to hFSH in its ability to bind and stimulate FSH receptors. The altered binding specificity displayed by this analog is not attributable solely to the replacement of hCGβ residues 108-145 or substitution of residues in the determinant loop located between hCDβ residues 93 and 100

  9. A Drosophila gene encoding a protein resembling the human β-amyloid protein precursor

    International Nuclear Information System (INIS)

    Rosen, D.R.; Martin-Morris, L.; Luo, L.; White, K.

    1989-01-01

    The authors have isolated genomic and cDNA clones for a Drosophila gene resembling the human β-amyloid precursor protein (APP). This gene produces a nervous system-enriched 6.5-kilobase transcript. Sequencing of cDNAs derived from the 6.5-kilobase transcript predicts an 886-amino acid polypeptide. This polypeptide contains a putative transmembrane domain and exhibits strong sequence similarity to cytoplasmic and extracellular regions of the human β-amyloid precursor protein. There is a high probability that this Drosophila gene corresponds to the essential Drosophila locus vnd, a gene required for embryonic nervous system development

  10. Proteomic profiling of human plasma exosomes identifies PPARγ as an exosome-associated protein

    International Nuclear Information System (INIS)

    Looze, Christopher; Yui, David; Leung, Lester; Ingham, Matthew; Kaler, Maryann; Yao, Xianglan; Wu, Wells W.; Shen Rongfong; Daniels, Mathew P.; Levine, Stewart J.

    2009-01-01

    Exosomes are nanovesicles that are released from cells as a mechanism of cell-free intercellular communication. Only a limited number of proteins have been identified from the plasma exosome proteome. Here, we developed a multi-step fractionation scheme incorporating gel exclusion chromatography, rate zonal centrifugation through continuous sucrose gradients, and high-speed centrifugation to purify exosomes from human plasma. Exosome-associated proteins were separated by SDS-PAGE and 66 proteins were identified by LC-MS/MS, which included both cellular and extracellular proteins. Furthermore, we identified and characterized peroxisome proliferator-activated receptor-γ (PPARγ), a nuclear receptor that regulates adipocyte differentiation and proliferation, as well as immune and inflammatory cell functions, as a novel component of plasma-derived exosomes. Given the important role of exosomes as intercellular messengers, the discovery of PPARγ as a component of human plasma exosomes identifies a potential new pathway for the paracrine transfer of nuclear receptors.

  11. A human activity approach to User Interfaces

    DEFF Research Database (Denmark)

    Bødker, Susanne

    1989-01-01

    the work situations in which computer-based artifacts are used: The framework deals with the role of the user interface in purposeful human work. Human activity theory is used in this analysis. The purpose of this article is to make the reader curious and hopefully open his or her eyes to a somewhat...

  12. Neutron scattering studies on protein dynamics using the human myelin peripheral membrane protein P2

    Directory of Open Access Journals (Sweden)

    Laulumaa Saara

    2015-01-01

    Full Text Available Myelin is a multilayered proteolipid membrane structure surrounding selected axons in the vertebrate nervous system, which allows the rapid saltatory conduction of nerve impulses. Deficits in myelin formation and maintenance may lead to chronic neurological disease. P2 is an abundant myelin protein from peripheral nerves, binding between two apposing lipid bilayers. We studied the dynamics of the human myelin protein P2 and its mutated P38G variant in hydrated powders using elastic incoherent neutron scattering. The local harmonic vibrations at low temperatures were very similar for both samples, but the mutant protein had increased flexibility and softness close to physiological temperatures. The results indicate that a drastic mutation of proline to glycine at a functional site can affect protein dynamics, and in the case of P2, they may explain functional differences between the two proteins.

  13. Neutron scattering studies on protein dynamics using the human myelin peripheral membrane protein P2

    Science.gov (United States)

    Laulumaa, Saara; Kursula, Petri; Natali, Francesca

    2015-01-01

    Myelin is a multilayered proteolipid membrane structure surrounding selected axons in the vertebrate nervous system, which allows the rapid saltatory conduction of nerve impulses. Deficits in myelin formation and maintenance may lead to chronic neurological disease. P2 is an abundant myelin protein from peripheral nerves, binding between two apposing lipid bilayers. We studied the dynamics of the human myelin protein P2 and its mutated P38G variant in hydrated powders using elastic incoherent neutron scattering. The local harmonic vibrations at low temperatures were very similar for both samples, but the mutant protein had increased flexibility and softness close to physiological temperatures. The results indicate that a drastic mutation of proline to glycine at a functional site can affect protein dynamics, and in the case of P2, they may explain functional differences between the two proteins.

  14. Protein C activity and antigen levels in childhood

    NARCIS (Netherlands)

    van Teunenbroek, A.; Peters, M.; Sturk, A.; Borm, J. J.; Breederveld, C.

    1990-01-01

    Hereditary protein C deficiency is an important risk factor for thrombosis. To enable its diagnosis shortly after birth, we determined reference values of protein C antigen and activity levels for the first 3 months of life. To establish an age-related range of protein C levels we also determined

  15. Deorphanizing the human transmembrane genome: A landscape of uncharacterized membrane proteins.

    Science.gov (United States)

    Babcock, Joseph J; Li, Min

    2014-01-01

    The sequencing of the human genome has fueled the last decade of work to functionally characterize genome content. An important subset of genes encodes membrane proteins, which are the targets of many drugs. They reside in lipid bilayers, restricting their endogenous activity to a relatively specialized biochemical environment. Without a reference phenotype, the application of systematic screens to profile candidate membrane proteins is not immediately possible. Bioinformatics has begun to show its effectiveness in focusing the functional characterization of orphan proteins of a particular functional class, such as channels or receptors. Here we discuss integration of experimental and bioinformatics approaches for characterizing the orphan membrane proteome. By analyzing the human genome, a landscape reference for the human transmembrane genome is provided.

  16. Membrane alterations induced by nonstructural proteins of human norovirus.

    Directory of Open Access Journals (Sweden)

    Sylvie Y Doerflinger

    2017-10-01

    Full Text Available Human noroviruses (huNoV are the most frequent cause of non-bacterial acute gastroenteritis worldwide, particularly genogroup II genotype 4 (GII.4 variants. The viral nonstructural (NS proteins encoded by the ORF1 polyprotein induce vesical clusters harboring the viral replication sites. Little is known so far about the ultrastructure of these replication organelles or the contribution of individual NS proteins to their biogenesis. We compared the ultrastructural changes induced by expression of norovirus ORF1 polyproteins with those induced upon infection with murine norovirus (MNV. Characteristic membrane alterations induced by ORF1 expression resembled those found in MNV infected cells, consisting of vesicle accumulations likely built from the endoplasmic reticulum (ER which included single membrane vesicles (SMVs, double membrane vesicles (DMVs and multi membrane vesicles (MMVs. In-depth analysis using electron tomography suggested that MMVs originate through the enwrapping of SMVs with tubular structures similar to mechanisms reported for picornaviruses. Expression of GII.4 NS1-2, NS3 and NS4 fused to GFP revealed distinct membrane alterations when analyzed by correlative light and electron microscopy. Expression of NS1-2 induced proliferation of smooth ER membranes forming long tubular structures that were affected by mutations in the active center of the putative NS1-2 hydrolase domain. NS3 was associated with ER membranes around lipid droplets (LDs and induced the formation of convoluted membranes, which were even more pronounced in case of NS4. Interestingly, NS4 was the only GII.4 protein capable of inducing SMV and DMV formation when expressed individually. Our work provides the first ultrastructural analysis of norovirus GII.4 induced vesicle clusters and suggests that their morphology and biogenesis is most similar to picornaviruses. We further identified NS4 as a key factor in the formation of membrane alterations of huNoV and

  17. Protein tyrosine adduct in humans self-poisoned by chlorpyrifos

    International Nuclear Information System (INIS)

    Li, Bin; Eyer, Peter; Eddleston, Michael; Jiang, Wei; Schopfer, Lawrence M.; Lockridge, Oksana

    2013-01-01

    Studies of human cases of self-inflicted poisoning suggest that chlorpyrifos oxon reacts not only with acetylcholinesterase and butyrylcholinesterase but also with other blood proteins. A favored candidate is albumin because in vitro and animal studies have identified tyrosine 411 of albumin as a site covalently modified by organophosphorus poisons. Our goal was to test this proposal in humans by determining whether plasma from humans poisoned by chlorpyrifos has adducts on tyrosine. Plasma samples from 5 self-poisoned humans were drawn at various time intervals after ingestion of chlorpyrifos for a total of 34 samples. All 34 samples were analyzed for plasma levels of chlorpyrifos and chlorpyrifos oxon (CPO) as a function of time post-ingestion. Eleven samples were analyzed for the presence of diethoxyphosphorylated tyrosine by mass spectrometry. Six samples yielded diethoxyphosphorylated tyrosine in pronase digests. Blood collected as late as 5 days after chlorpyrifos ingestion was positive for CPO-tyrosine, consistent with the 20-day half-life of albumin. High plasma CPO levels did not predict detectable levels of CPO-tyrosine. CPO-tyrosine was identified in pralidoxime treated patients as well as in patients not treated with pralidoxime, indicating that pralidoxime does not reverse CPO binding to tyrosine in humans. Plasma butyrylcholinesterase was a more sensitive biomarker of exposure than adducts on tyrosine. In conclusion, chlorpyrifos oxon makes a stable covalent adduct on the tyrosine residue of blood proteins in humans who ingested chlorpyrifos. - Highlights: • Chlorpyrifos-poisoned patients have adducts on protein tyrosine. • Diethoxyphosphate-tyrosine does not lose an alkyl group. • Proteins in addition to AChE and BChE are modified by organophosphates

  18. Protein tyrosine adduct in humans self-poisoned by chlorpyrifos

    Energy Technology Data Exchange (ETDEWEB)

    Li, Bin, E-mail: binli@unmc.edu [Eppley Institute, University of Nebraska Medical Center, Omaha, NE 68198-5950 (United States); Eyer, Peter, E-mail: peter.eyer@lrz.uni-muenchen.de [Walther-Straub-Institut Für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, 80336 München (Germany); Eddleston, Michael, E-mail: M.Eddleston@ed.ac.uk [Clinical Pharmacology Unit, University of Edinburgh, Edinburgh (United Kingdom); Jiang, Wei, E-mail: wjiang@unmc.edu [Eppley Institute, University of Nebraska Medical Center, Omaha, NE 68198-5950 (United States); Schopfer, Lawrence M., E-mail: lmschopf@unmc.edu [Eppley Institute, University of Nebraska Medical Center, Omaha, NE 68198-5950 (United States); Lockridge, Oksana, E-mail: olockrid@unmc.edu [Eppley Institute, University of Nebraska Medical Center, Omaha, NE 68198-5950 (United States)

    2013-06-15

    Studies of human cases of self-inflicted poisoning suggest that chlorpyrifos oxon reacts not only with acetylcholinesterase and butyrylcholinesterase but also with other blood proteins. A favored candidate is albumin because in vitro and animal studies have identified tyrosine 411 of albumin as a site covalently modified by organophosphorus poisons. Our goal was to test this proposal in humans by determining whether plasma from humans poisoned by chlorpyrifos has adducts on tyrosine. Plasma samples from 5 self-poisoned humans were drawn at various time intervals after ingestion of chlorpyrifos for a total of 34 samples. All 34 samples were analyzed for plasma levels of chlorpyrifos and chlorpyrifos oxon (CPO) as a function of time post-ingestion. Eleven samples were analyzed for the presence of diethoxyphosphorylated tyrosine by mass spectrometry. Six samples yielded diethoxyphosphorylated tyrosine in pronase digests. Blood collected as late as 5 days after chlorpyrifos ingestion was positive for CPO-tyrosine, consistent with the 20-day half-life of albumin. High plasma CPO levels did not predict detectable levels of CPO-tyrosine. CPO-tyrosine was identified in pralidoxime treated patients as well as in patients not treated with pralidoxime, indicating that pralidoxime does not reverse CPO binding to tyrosine in humans. Plasma butyrylcholinesterase was a more sensitive biomarker of exposure than adducts on tyrosine. In conclusion, chlorpyrifos oxon makes a stable covalent adduct on the tyrosine residue of blood proteins in humans who ingested chlorpyrifos. - Highlights: • Chlorpyrifos-poisoned patients have adducts on protein tyrosine. • Diethoxyphosphate-tyrosine does not lose an alkyl group. • Proteins in addition to AChE and BChE are modified by organophosphates.

  19. Animal Proteins as Important Contributors to a Healthy Human Diet.

    Science.gov (United States)

    Elmadfa, Ibrahim; Meyer, Alexa L

    2017-02-08

    Adequate protein intake is critical for health and development. Generally, protein of animal origin is of higher quality for humans owing to its amino acid pattern and good digestibility. When administered in mixtures it can enhance the quality of plant proteins, but its availability is often low in low-income communities, especially in young children, the elderly, and pregnant and lactating women, who have increased requirements and in whom high-quality protein also stimulates (bone) growth and maintenance. Although high protein intake was associated with increased type 2 diabetes mellitus risk, milk and seafood are good sources of branched chain amino acids and taurine, which act beneficially on glucose metabolism and blood pressure. However, high consumption of protein-rich animal food is also associated with adverse health effects and higher risk for noncommunicable diseases, partly related to other components of these foods, like saturated fatty acids and potential carcinogens in processed meat but also the atherogenic methionine metabolite homocysteine. In moderation, however, animal proteins are especially important for health maintenance in vulnerable persons.

  20. Characterization of tissue plasminogen activator binding proteins isolated from endothelial cells and other cell types

    International Nuclear Information System (INIS)

    Beebe, D.P.; Wood, L.L.; Moos, M.

    1990-01-01

    Human tissue plasminogen activator (t-PA) was shown to bind specifically to human osteosarcoma cells (HOS), and human epidermoid carcinoma cells (A-431 cells). Crosslinking studies with DTSSP demonstrated high molecular weight complexes (130,000) between 125 I-t-PA and cell membrane protein on human umbilical vein endothelial cells (HUVEC), HOS, and A-431 cells. A 48-65,000 molecular weight complex was demonstrated after crosslinking t-PA peptide (res. 7-20) to cells. Ligand blotting of cell lysates which had been passed over a t-PA affinity column revealed binding of t-PA to 54,000 and 95,000 molecular weight proteins. Several t-PA binding proteins were identified in immunopurified cell lysates, including tubulin beta chain, plasminogen activator inhibitor type 1 and single chain urokinase

  1. Neuronal Functions of Activators of G Protein Signaling

    Directory of Open Access Journals (Sweden)

    Man K. Tse

    2012-05-01

    Full Text Available G protein-coupled receptors (GPCRs are one of the most important gateways for signal transduction across the plasma membrane. Over the past decade, several classes of alternative regulators of G protein signaling have been identified and reported to activate the G proteins independent of the GPCRs. One group of such regulators is the activator of G protein signaling (AGS family which comprises of AGS1-10. They have entirely different activation mechanisms for G proteins as compared to the classic model of GPCR-mediated signaling and confer upon cells new avenues of signal transduction. As GPCRs are widely expressed in our nervous system, it is believed that the AGS family plays a major role in modulating the G protein signaling in neurons. In this article, we will review the current knowledge on AGS proteins in relation to their potential roles in neuronal regulations.

  2. Rescuing the Rescuer: On the Protein Complex between the Human Mitochondrial Acyl Carrier Protein and ISD11.

    Science.gov (United States)

    Herrera, María Georgina; Pignataro, María Florencia; Noguera, Martín Ezequiel; Cruz, Karen Magalí; Santos, Javier

    2018-05-16

    Iron-sulfur clusters are essential cofactors in many biochemical processes. ISD11, one of the subunits of the protein complex that carries out the cluster assembly in mitochondria, is necessary for cysteine desulfurase NFS1 stability and function. Several authors have recently provided evidence showing that ISD11 interacts with the acyl carrier protein (ACP). We carried out the coexpression of human mitochondrial ACP and ISD11 in E. coli. This work shows that ACP and ISD11 form a soluble, structured, and stable complex able to bind to the human NFS1 subunit modulating its activity. Results suggest that ACP plays a key-role in ISD11 folding and stability in vitro. These findings offer the opportunity to study the mechanism of interaction between ISD11 and NFS1.

  3. Effect of pregnancy-associated plasma protein-A (PAPP-A) single-nucleotide polymorphisms on the level and activity of PAPP-A and the hormone profile in fluid from normal human small antral follicles

    DEFF Research Database (Denmark)

    Bøtkjær, Jane Alrø; Borgbo, Tanni; Kløverpris, Søren

    2016-01-01

    Objective: To reveal a possible relationship between two single nucleotide polymorphisms (SNPs) in PAPP-A—1224 (rs7020782) and 327 (rs12375498)—and the level and activity of PAPP-A in follicular fluid (FF) of human small antral follicles, and to analyze the intrafollicular hormone levels. Design:...

  4. Nonstructural Protein L* Species Specificity Supports a Mouse Origin for Vilyuisk Human Encephalitis Virus.

    Science.gov (United States)

    Drappier, Melissa; Opperdoes, Fred R; Michiels, Thomas

    2017-07-15

    Vilyuisk human encephalitis virus (VHEV) is a picornavirus related to Theiler's murine encephalomyelitis virus (TMEV). VHEV was isolated from human material passaged in mice. Whether this VHEV is of human or mouse origin is therefore unclear. We took advantage of the species-specific activity of the nonstructural L* protein of theiloviruses to track the origin of TMEV isolates. TMEV L* inhibits RNase L, the effector enzyme of the interferon pathway. By using coimmunoprecipitation and functional RNase L assays, the species specificity of RNase L antagonism was tested for L* from mouse (DA) and rat (RTV-1) TMEV strains as well as for VHEV. Coimmunoprecipitation and functional assay data confirmed the species specificity of L* activity and showed that L* from rat strain RTV-1 inhibited rat but not mouse or human RNase L. Next, we showed that the VHEV L* protein was phylogenetically related to L* of mouse viruses and that it failed to inhibit human RNase L but readily antagonized mouse RNase L, unambiguously showing the mouse origin of VHEV. IMPORTANCE Defining the natural host of a virus can be a thorny issue, especially when the virus was isolated only once or when the isolation story is complex. The species Theilovirus includes Theiler's murine encephalomyelitis virus (TMEV), infecting mice and rats, and Saffold virus (SAFV), infecting humans. One TMEV strain, Vilyuisk human encephalitis virus (VHEV), however, was isolated from mice that were inoculated with cerebrospinal fluid of a patient presenting with chronic encephalitis. It is therefore unclear whether VHEV was derived from the human sample or from the inoculated mouse. The L* protein encoded by TMEV inhibits RNase L, a cellular enzyme involved in innate immunity, in a species-specific manner. Using binding and functional assays, we show that this species specificity even allows discrimination between TMEV strains of mouse and of rat origins. The VHEV L* protein clearly inhibited mouse but not human RNase L

  5. Protein biosynthesis in cultured human hair follicle cells.

    Science.gov (United States)

    Weterings, P J; Vermorken, A J; Bloemendal, H

    1980-10-31

    A new technique has been used for culturing human keratinocytes. The cells grow on the basement membrane-like capsules of bovine lenses. Lens cells were removed from the capsules by rigid trypsinization. In order to exclude any contamination with remaining living cells the isolated capsules were irradiated with X-rays at a dose of 10,000 rad. In this way human epithelial cells can be brought in culture from individual hair follicles. Since feeder cells are not used in this culture technique, the biosynthesis of keratinocyte proteins can be studied in these cultures. The newly synthesized proteins can be separated into a water-soluble, a urea-soluble, and a urea-insoluble fraction. Product analysis has been performed on the first two fractions revealing protein patterns identical to those of intact hair follicles. Product analysis of the urea-soluble fractions of microdissected hair follicles shows that the protein pattern of the cultured keratinocytes resembles the protein pattern of the hair follicle sheath. Studies on the metabolism of benzo(a)pyrene revealed that the enzyme aryl hydrocarbon hydroxylase (AHH) is present in cultured hair follicle cells. A possible use of our culture system for eventual detection of inherited predisposition for smoking-dependent lung cancer is discussed.

  6. Protein tyrosine adduct in humans self-poisoned by chlorpyrifos

    Science.gov (United States)

    Li, Bin; Eyer, Peter; Eddleston, Michael; Jiang, Wei; Schopfer, Lawrence M.; Lockridge, Oksana

    2013-01-01

    Studies of human cases of self-inflicted poisoning suggest that chlorpyrifos oxon reacts not only with acetylcholinesterase and butyrylcholinesterase but also with other blood proteins. A favored candidate is albumin because in vitro and animal studies have identified tyrosine 411 of albumin as a site covalently modified by organophosphorus poisons. Our goal was to test this proposal in humans by determining whether plasma from humans poisoned by chlorpyrifos has adducts on tyrosine. Plasma samples from 5 self-poisoned humans were drawn at various time intervals after ingestion of chlorpyrifos for a total of 34 samples. All 34 samples were analyzed for plasma levels of chlorpyrifos and chlorpyrifos oxon (CPO) as a function of time post-ingestion. Eleven samples were analyzed for the presence of diethoxyphosphorylated tyrosine by mass spectrometry. Six samples yielded diethoxyphosphorylated tyrosine in pronase digests. Blood collected as late as 5 days after chlorpyrifos ingestion was positive for CPO-tyrosine, consistent with the 20-day half-life of albumin. High plasma CPO levels did not predict detectable levels of CPO-tyrosine. CPO-tyrosine was identified in pralidoxime treated patients as well as in patients not treated with pralidoxime, indicating that pralidoxime does not reverse CPO binding to tyrosine in humans. Plasma butyrylcholinesterase was a more sensitive biomarker of exposure than adducts on tyrosine. In conclusion, chlorpyrifos oxon makes a stable covalent adduct on the tyrosine residue of blood proteins in humans who ingested chlorpyrifos. PMID:23566956

  7. Association of the macrophage activating factor (MAF) precursor activity with polymorphism in vitamin D-binding protein.

    Science.gov (United States)

    Nagasawa, Hideko; Sasaki, Hideyuki; Uto, Yoshihiro; Kubo, Shinichi; Hori, Hitoshi

    2004-01-01

    Serum vitamin D-binding protein (Gc protein or DBP) is a highly expressed polymorphic protein, which is a precursor of the inflammation-primed macrophage activating factor, GcMAF, by a cascade of carbohydrate processing reactions. In order to elucidate the relationship between Gc polymorphism and GcMAF precursor activity, we estimated the phagocytic ability of three homotypes of Gc protein, Gc1F-1F, Gc1S-1S and Gc2-2, through processing of their carbohydrate moiety. We performed Gc typing of human serum samples by isoelectric focusing (IEF). Gc protein from human serum was purified by affinity chromatography with 25-hydroxyvitamin D3-sepharose. A phagocytosis assay of Gc proteins, modified using beta-glycosidase and sialidase, was carried out. The Gc1F-1F phenotype was revealed to possess Galbeta1-4GalNAc linkage by the analysis of GcMAF precursor activity using beta1-4 linkage-specific galactosidase from jack bean. The GcMAF precursor activity of the Gc1F-1F phenotype was highest among three Gc homotypes. The Gc polymorphism and carbohydrate diversity of Gc protein are significant for its pleiotropic effects.

  8. Human body contour data based activity recognition.

    Science.gov (United States)

    Myagmarbayar, Nergui; Yuki, Yoshida; Imamoglu, Nevrez; Gonzalez, Jose; Otake, Mihoko; Yu, Wenwei

    2013-01-01

    This research work is aimed to develop autonomous bio-monitoring mobile robots, which are capable of tracking and measuring patients' motions, recognizing the patients' behavior based on observation data, and providing calling for medical personnel in emergency situations in home environment. The robots to be developed will bring about cost-effective, safe and easier at-home rehabilitation to most motor-function impaired patients (MIPs). In our previous research, a full framework was established towards this research goal. In this research, we aimed at improving the human activity recognition by using contour data of the tracked human subject extracted from the depth images as the signal source, instead of the lower limb joint angle data used in the previous research, which are more likely to be affected by the motion of the robot and human subjects. Several geometric parameters, such as, the ratio of height to weight of the tracked human subject, and distance (pixels) between centroid points of upper and lower parts of human body, were calculated from the contour data, and used as the features for the activity recognition. A Hidden Markov Model (HMM) is employed to classify different human activities from the features. Experimental results showed that the human activity recognition could be achieved with a high correct rate.

  9. Purification, crystallization and X-ray diffraction analysis of human dynamin-related protein 1 GTPase-GED fusion protein

    International Nuclear Information System (INIS)

    Klinglmayr, Eva; Wenger, Julia; Mayr, Sandra; Bossy-Wetzel, Ella; Puehringer, Sandra

    2012-01-01

    The crystallization and initial diffraction analysis of human Drp1 GTPase-GED fusion protein are reported. The mechano-enzyme dynamin-related protein 1 plays an important role in mitochondrial fission and is implicated in cell physiology. Dysregulation of Drp1 is associated with abnormal mitochondrial dynamics and neuronal damage. Drp1 shares structural and functional similarities with dynamin 1 with respect to domain organization, ability to self-assemble into spiral-like oligomers and GTP-cycle-dependent membrane scission. Structural studies of human dynamin-1 have greatly improved the understanding of this prototypical member of the dynamin superfamily. However, high-resolution structural information for full-length human Drp1 covering the GTPase domain, the middle domain and the GTPase effector domain (GED) is still lacking. In order to obtain mechanistic insights into the catalytic activity, a nucleotide-free GTPase-GED fusion protein of human Drp1 was expressed, purified and crystallized. Initial X-ray diffraction experiments yielded data to 2.67 Å resolution. The hexagonal-shaped crystals belonged to space group P2 1 2 1 2, with unit-cell parameters a = 53.59, b = 151.65, c = 43.53 Å, one molecule per asymmetric unit and a solvent content of 42%. Expression of selenomethionine-labelled protein is currently in progress. Here, the expression, purification, crystallization and X-ray diffraction analysis of the Drp1 GTPase-GED fusion protein are presented, which form a basis for more detailed structural and biophysical analysis

  10. Phospholipid transfer protein activity and incident type 2 diabetes mellitus

    NARCIS (Netherlands)

    Abbasi, Ali; Dallinga-Thie, Geesje M.; Dullaart, Robin P. F.

    2015-01-01

    Background: The plasma activity of phospholipid transfer protein (PLTP), which has multifaceted functions in lipoprotein metabolism and in inflammatory responses, is elevated in insulin resistant conditions. We determined the association of plasma PLTP activity with incident type 2 diabetes mellitus

  11. RNA-Guided Activation of Pluripotency Genes in Human Fibroblasts

    DEFF Research Database (Denmark)

    Xiong, Kai; Zhou, Yan; Blichfeld, Kristian Aabo

    2017-01-01

    -associated protein 9 (dCas9)-VP64 (CRISPRa) alone, or a combination of dCas9-VP64 and MS2-P65-HSF1 [synergistic activation mediator (SAM) system] mediated activation of five pluripotency genes: KLF4 (K), LIN28 (L), MYC (M), OCT4 (O), and SOX2 (S) in human cells (HEK293T, HeLa, HepG2, and primary fibroblasts...... could be obtained from these SAM fibroblasts. In conclusion, our study showed that CRISPR/Cas9-based ATFs are potent to activate and maintain transcription of endogenous human pluripotent genes. However, future improvements of the system are still required to improve activation efficiency and cellular...

  12. Production of biologically active recombinant human factor H in Physcomitrella.

    Science.gov (United States)

    Büttner-Mainik, Annette; Parsons, Juliana; Jérôme, Hanna; Hartmann, Andrea; Lamer, Stephanie; Schaaf, Andreas; Schlosser, Andreas; Zipfel, Peter F; Reski, Ralf; Decker, Eva L

    2011-04-01

    The human complement regulatory serum protein factor H (FH) is a promising future biopharmaceutical. Defects in the gene encoding FH are associated with human diseases like severe kidney and retinal disorders in the form of atypical haemolytic uremic syndrome (aHUS), membranoproliferative glomerulonephritis II (MPGN II) or age-related macular degeneration (AMD). There is a current need to apply intact full-length FH for the therapy of patients with congenital or acquired defects of this protein. Application of purified or recombinant FH (rFH) to these patients is an important and promising approach for the treatment of these diseases. However, neither protein purified from plasma of healthy individuals nor recombinant protein is currently available on the market. Here, we report the first stable expression of the full-length human FH cDNA and the subsequent production of this glycoprotein in a plant system. The moss Physcomitrella patens perfectly suits the requirements for the production of complex biopharmaceuticals as this eukaryotic system not only offers an outstanding genetical accessibility, but moreover, proteins can be produced safely in scalable photobioreactors without the need for animal-derived medium compounds. Transgenic moss lines were created, which express the human FH cDNA and target the recombinant protein to the culture supernatant via a moss-derived secretion signal. Correct processing of the signal peptide and integrity of the moss-produced rFH were verified via peptide mapping by mass spectrometry. Ultimately, we show that the rFH displays complement regulatory activity comparable to FH purified from plasma. © 2010 The Authors. Plant Biotechnology Journal © 2010 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

  13. Anti-complement activities of human breast-milk.

    Science.gov (United States)

    Ogundele, M O

    1999-08-01

    It has long been observed that the human milk possesses significant anti-inflammatory properties, while simultaneously protecting the infant against many intestinal and respiratory pathogens. There is, however, a paucity of information on the degree and extent of this anti-inflammatory activity. In the present study, the inhibitory effects of different fractions of human milk on serum complement activity were analysed. Colostrum and milk samples from healthy voluntary lactating donors at different postpartum ages were obtained and pooled normal human serum was used as source of complement in a modified CH50 assay. Inherent complement activity in human milk was also investigated by measuring the deposition of an activated C3 fragment on a serum-sensitive bacteria, and by haemolytic assays. Most whole- and defatted-milk samples consistently showed a dose-dependent inhibition of the serum complement activity. This inhibition was greater in mature milk compared to transitional milk samples. It was enhanced by inactivation of milk complement, and diminished by centrifugation of milk samples, which partly removed fat and larger protein components including casein micelles. Inherent complement activity in human milk was also demonstrated by haemolysis of sensitised sheep erythrocytes and deposition of C3 fragments on solid-phase bacteria. These activities were highest in the colostrum and gradually decreased as lactation proceeded. Several natural components abundant in the fluid phase of the human breast-milk have been shown to be inhibitors of complement activation in vitro. Their physiological significance probably reside in their ability to prevent inflammatory-induced tissue damage of the delicate immature gastrointestinal tract of the new-born as well as the mammary gland itself, which may arise from ongoing complement activation.

  14. Preparation of Gc protein-derived macrophage activating factor (GcMAF) and its structural characterization and biological activities.

    Science.gov (United States)

    Mohamad, Saharuddin Bin; Nagasawa, Hideko; Uto, Yoshihiro; Hori, Hitoshi

    2002-01-01

    Gc protein has been reported to be a precursor of Gc protein-derived macrophage activation factor (GcMAF) in the inflammation-primed macrophage activation cascade. An inducible beta-galactosidase of B cells and neuraminidase of T cells convert Gc protein to GcMAF. Gc protein from human serum was purified using 25(OH)D3 affinity column chromatography and modified to GcMAF using immobilized glycosidases (beta-galactosidase and neuraminidase) The sugar moiety structure of GcMAF was characterized by lectin blotting by Helix pomatia agglutinin. The biological activities of GcMAF were evaluated by a superoxide generation assay and a phagocytosis assay. We successfully purified Gc protein from human serum. GcMAF was detected by lectin blotting and showed a high biological activity. Our results support the importance of the terminal N-acetylgalactosamine moiety in the GcMAF-mediated macrophage activation cascade, and the existence of constitutive GcMAF in human serum. These preliminary data are important for designing small molecular GcMAF mimics.

  15. Nutrient Fortification of Human Donor Milk Affects Intestinal Function and Protein Metabolism in Preterm Pigs

    DEFF Research Database (Denmark)

    Sun, Jing; Li, Yanqi; Nguyen, Duc Ninh

    2018-01-01

    (BC) may be an alternative nutrient fortifier, considering its high content of protein and milk bioactive factors. Objective: We investigated whether BC was superior to an FF product based on processed bovine milk and vegetable oil to fortify donor human milk (DHM) for preterm pigs, used as a model......) and DHM with or without FF or BC fortification (+4.6 g protein ⋅ kg-1 ⋅ d-1). Results: DPM-fed pigs showed higher growth (10-fold), protein synthesis (+15-30%), villus heights, lactase and peptidase activities (+30%), and reduced intestinal cytokines (-50%) relative to DHM pigs (all P ....05). Fortification increased protein synthesis (+20-30%), but with higher weight gain and lower urea and cortisol concentrations for DHM+BC compared with DHM+FF pigs (2- to 3-fold differences, all P ≤ 0.06). DHM+FF pigs showed more diarrhea and reduced lactase and peptidase activities, hexose uptake, and villus...

  16. Modulation of Spc1 stress-activated protein kinase activity by methylglyoxal through inhibition of protein phosphatase in the fission yeast Schizosaccharomyces pombe

    International Nuclear Information System (INIS)

    Takatsume, Yoshifumi; Izawa, Shingo; Inoue, Yoshiharu

    2007-01-01

    Methylglyoxal, a ubiquitous metabolite derived from glycolysis has diverse physiological functions in yeast cells. Previously, we have reported