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Sample records for adam protein mimics

  1. Synthetic Peptides as Protein Mimics

    PubMed Central

    Groß, Andrea; Hashimoto, Chie; Sticht, Heinrich; Eichler, Jutta

    2016-01-01

    The design and generation of molecules capable of mimicking the binding and/or functional sites of proteins represents a promising strategy for the exploration and modulation of protein function through controlled interference with the underlying molecular interactions. Synthetic peptides have proven an excellent type of molecule for the mimicry of protein sites because such peptides can be generated as exact copies of protein fragments, as well as in diverse chemical modifications, which includes the incorporation of a large range of non-proteinogenic amino acids as well as the modification of the peptide backbone. Apart from extending the chemical and structural diversity presented by peptides, such modifications also increase the proteolytic stability of the molecules, enhancing their utility for biological applications. This article reviews recent advances by this and other laboratories in the use of synthetic protein mimics to modulate protein function, as well as to provide building blocks for synthetic biology. PMID:26835447

  2. [The importance of ADAM family proteins in malignant tumors].

    PubMed

    Walkiewicz, Katarzyna; Gętek, Monika; Muc-Wierzgoń, Małgorzata; Kokot, Teresa; Nowakowska-Zajdel, Ewa

    2016-02-11

    Increasing numbers of reports about the role of adamalysins (ADAM) in malignant tumors are being published. To date, more than 30 representatives of this group, out of which about 20 occur in humans, have been described. The ADAM family is a homogeneous group of proteins which regulate, from the stage of embryogenesis, a series of processes such as cell migration, adhesion, and cell fusion. Half of them have proteolytic activity and are involved in the degradation of the extracellular matrix and the disintegration of certain protein complexes, thereby regulating the bioavailability of various growth factors. Many of these functions have a direct role in the processes of carcinogenesis and promoting the growth of tumor, which affect some signaling pathways, including those related to insulin-like growth factors (IGF1, IGF2), vascular growth factor (VEGF), tumor necrosis factor α (TNFα) and the EGFR/HER pathway. Another branch of studies is the evaluation of the possibility of using members of ADAM family proteins in the diagnosis, especially in breast, colon and non- small cell lung cancer. The detection of concentrations of adamalysin in serum, urine and pleural aspirates might contribute to the development of methods of early diagnosis of cancer and monitoring the therapy. However, both the role of adamalysins in the development and progression of tumors and their importance as a diagnostic and predictive further research still need to be checked on large groups of patients.

  3. ADAM12 transmembrane and secreted isoforms promote breast tumor growth: a distinct role for ADAM12-S protein in tumor metastasis.

    PubMed

    Roy, Roopali; Rodig, Scott; Bielenberg, Diane; Zurakowski, David; Moses, Marsha A

    2011-06-10

    Increased levels of ADAM12 have been reported in a variety of human cancers. We have previously reported that urinary ADAM12 is predictive of disease status in breast cancer patients and that ADAM12 protein levels in urine increase with progression of disease. On the basis of these findings, the goal of this study was to elucidate the contribution of ADAM12 in breast tumor growth and progression. Overexpression of both the ADAM12-L (transmembrane) and ADAM12-S (secreted) isoforms in human breast tumor cells resulted in a significantly higher rate of tumor take and increased tumor size. Cells expressing the enzymatically inactive form of the secreted isoform, ADAM12-S, had tumor take rates and tumor volumes similar to those of wild-type cells, suggesting that the tumor-promoting activity of ADAM12-S was a function of its proteolytic activity. Of the two isoforms, only the secreted isoform, ADAM12-S, enhanced the ability of tumor cells to migrate and invade in vitro and resulted in a higher incidence of local and distant metastasis in vivo. This stimulatory effect of ADAM12-S on migration and invasion was dependent on its catalytic activity. Expression of both ADAM12 isoforms was found to be significantly elevated in human malignant breast tissue. Taken together, our results suggest that ADAM12 overexpression results in increased tumor take, tumor size, and metastasis in vivo. These findings suggest that ADAM12 may represent a potential therapeutic target in breast cancer.

  4. Species Specificity of ADAM10 and ADAM17 Proteins in Interleukin-6 (IL-6) Trans-signaling and Novel Role of ADAM10 in Inducible IL-6 Receptor Shedding*

    PubMed Central

    Garbers, Christoph; Jänner, Nathalie; Chalaris, Athena; Moss, Marcia L.; Floss, Doreen M.; Meyer, Dörte; Koch-Nolte, Friedrich; Rose-John, Stefan; Scheller, Jürgen

    2011-01-01

    Hypomorphic ADAM17ex/ex mice showed defects in mucosal regeneration due to inefficient enhanced GFR shedding. ADAM17 is the main sheddase of interleukin-6 receptor (IL-6R) to induce IL-6 trans-signaling. However, serum levels of soluble murine IL-6R were not reduced in ADAM17ex/ex mice, and murine ADAM17 was not the major sheddase of murine IL-6R. Shedding of murine IL-6R by murine ADAM17 was rescued in chimeric murine IL-6R proteins containing any extracellular domain but not the transmembrane and intracellular domain of human IL-6R. Apoptosis is a physiological stimulus of ADAM17-mediated shedding of human IL-6R. Even though apoptosis induced IL-6R shedding in mice, the responsible protease was identified as ADAM10. ADAM10 also was identified as protease responsible for ionomycin-induced shedding of murine and human IL-6R. However, in ADAM10-deficient murine embryonic fibroblasts, compensatory shedding of human IL-6R was mediated by ADAM17, but loss of ADAM10-mediated shedding of murine IL-6R was compensated by an as-yet-unidentified protease. Finally, we identified physiological purinergic P2X7 receptor stimulation as a novel inducer of murine and human IL-6R shedding solely mediated by ADAM10. In conclusion, we describe an unexpected species specificity of ADAM10 and ADAM17 and identified ADAM10 as novel inducible sheddase of IL-6R in mice and humans, which might have consequences for the interpretation of phenotypes from ADAM17- and ADAM10-deficient mice. PMID:21454673

  5. Peptoid mimics of agouti related protein.

    PubMed

    Thompson, Darren A; Chai, Biao-Xin; Rood, Hilary L E; Siani, Michael A; Douglas, Nicholai R; Gantz, Ira; Millhauser, Glenn L

    2003-04-17

    The Agouti Related Protein (AGRP) is an endogenous antagonist of melanocortin-3 and -4 receptors, each of which plays a key role in body weight homeostasis. We designed a peptoid trimer based on AGRP 111-113 in which a single chiral atom is used to partially restrain the backbone structure. Peptoid 5 displaced both radiolabeled Nle4-alpha-MSH (IC(50)=3.1 microM) and AGRP (86-132) (IC(50)=1.9 microM) from the human melanocortin-4 receptor and functioned as an antagonist of alpha-MSH stimulated cAMP generation, thus providing an important lead in the development of AGRP mimetics.

  6. RACK1, a new ADAM12 interacting protein. Contribution to liver fibrogenesis.

    PubMed

    Bourd-Boittin, Katia; Le Pabic, Hélène; Bonnier, Dominique; L'Helgoualc'h, Annie; Théret, Nathalie

    2008-09-19

    ADAM12 belongs to a disintegrin-like and metalloproteinase-containing protein family that possesses multidomain structures composed of a pro-domain, a metalloprotease, disintegrin-like, cysteine-rich, epidermal growth factor-like, and transmembrane domains, and a cytoplasmic tail. Overexpression of several ADAMs has been reported in human cancer, and we recently described the involvement of ADAM12 in liver injury (Le Pabic, H., Bonnier, D., Wewer, U. M., Coutand, A., Musso, O., Baffet, G., Clement, B., and Theret, N. (2003) Hepatology 37, 1056-1066). In this study, we used a yeast two-hybrid screening of a cDNA library from human hepatocellular carcinoma to analyze binding partners of ADAM12. We identify RACK1, a receptor for activated protein kinase C (PKC), as a new ADAM12 interacting protein. RACK1 is up-regulated in patients with hepatocellular carcinoma and is highly expressed by activated hepatic stellate cells. We demonstrate the involvement of RACK1 in mediating the PKC-dependent translocation of ADAM12 to membranes of activated hepatic stellate cells. In particular, treatment of cells with phorbol esters enhances ADAM12 immunostaining in the membrane fractions and the co-immunoprecipitation of ternary complexes containing RACK1, ADAM12, and PKC. By using RNA interference, we demonstrate that inhibition of RACK1 expression diminishes the phorbol 12-myristate 13-acetate-dependent translocation of ADAM12 to membranes of hepatic stellate cells. Finally, hepatic stellate cells cultured on coated type I collagen induces relocalization of ADAM12 in the membrane, suggesting that this major matrix component in liver cancer and fibrogenesis might stimulate ADAM12 translocation to the cell membrane where its shedding activity takes place.

  7. ADAM and ADAMTS Family Proteins and Snake Venom Metalloproteinases: A Structural Overview

    PubMed Central

    Takeda, Soichi

    2016-01-01

    A disintegrin and metalloproteinase (ADAM) family proteins constitute a major class of membrane-anchored multidomain proteinases that are responsible for the shedding of cell-surface protein ectodomains, including the latent forms of growth factors, cytokines, receptors and other molecules. Snake venom metalloproteinases (SVMPs) are major components in most viper venoms. SVMPs are primarily responsible for hemorrhagic activity and may also interfere with the hemostatic system in envenomed animals. SVMPs are phylogenetically most closely related to ADAMs and, together with ADAMs and related ADAM with thrombospondin motifs (ADAMTS) family proteinases, constitute adamalysins/reprolysins or the M12B clan (MEROPS database) of metalloproteinases. Although the catalytic domain structure is topologically similar to that of other metalloproteinases such as matrix metalloproteinases, the M12B proteinases have a modular structure with multiple non-catalytic ancillary domains that are not found in other proteinases. Notably, crystallographic studies revealed that, in addition to the conserved metalloproteinase domain, M12B members share a hallmark cysteine-rich domain designated as the “ADAM_CR” domain. Despite their name, ADAMTSs lack disintegrin-like structures and instead comprise two ADAM_CR domains. This review highlights the current state of our knowledge on the three-dimensional structures of M12B proteinases, focusing on their unique domains that may collaboratively participate in directing these proteinases to specific substrates. PMID:27196928

  8. ADAM and ADAMTS family proteins and their role in the colorectal cancer etiopathogenesis

    PubMed Central

    Przemyslaw, Leszczynski; Boguslaw, Hendrich Andrzej; Elzbieta, Szmida; Malgorzata, Sasiadek Maria

    2013-01-01

    The ADAM and ADAMTS families, also called adamalysins belong to an important group of extracellular matrix proteins. The ADAMs family belong to both the transmembrane and secreted proteins, while ADAMTS family only contains secreted forms. Adamalysins play an important role in the cell phenotype regulation via their activities in signaling pathways, cell adhesion and migration. The human proteome contains 21 ADAM, and 19 ADAMTS proteins, which are involved in extracellular matrix remodeling, shedding of various substrates such as: adhesion ligands, growth factors, their receptors and diverse cytokines. Recent studies provide evidence that adamalysins play a crucial role in colorectal cancer (CRC) etiopathogenesis. It seems possible that adamalysins might be used as CRC prediction markers or potential pharmaceutical targets. [BMB Reports 2013; 46(3): 139-150] PMID:23527857

  9. Association of ADAM12-S protein with radiographic features of knee osteoarthritis and bone and cartilage markers.

    PubMed

    Kerna, I; Kisand, K; Laitinen, P; Tamm, A E; Kumm, J; Lintrop, M; Tamm, A O

    2012-02-01

    ADAM12 (A disintegrin and metalloprotease) is one of the candidate genes demonstrating susceptibility to osteoarthritis. The purpose of this study was to investigate the relationship between ADAM12-S protein and radiographic knee osteoarthritis (KOA) and its correlation to several bone and cartilage biomarkers. The ADAM12-S protein was measured in 276 subjects (60% women, aged 32-60 years), including 181 individuals with and 95 without radiographic KOA features. The radiographs were obtained from both tibiofemoral (TF) and patellofemoral (PF) joints. The serum levels of ADAM12-S protein were measured by DELFIA1/AutoDELFIA research kit. The ADAM12-S protein was found in detectable ranges in 43 subjects (16 men), without statistical difference between the two genders. In the whole group, the ADAM12-S was related to radiographic KOA grades in TF (P = 0.004) as well in PF joint (P = 0.003). We also found a correlation between ADAM12-S protein and osteophytes in TF and/or PF joints (P = 0.003). No correlations were found between serum levels of S-CTx-I (C-terminal cross-linked telopeptides of type I collagen) or S-PINP (type I procollagen N-terminal propeptide) and ADAM12-S. Similarly, in the whole group, the ADAM12-S protein was not correlated with U-CTx-II (urinary C-telopeptide fragments of type II collagen); however, in the female group, trend to positive correlation between the investigated biomarkers (P = 0.019) was observed. The ADAM12-S protein could be elevated in some KOA cases, and this elevation correlates with the grades of the disease, mostly owning to development of osteophytes. This finding suggests the possible involvement of the ADAM12-S protein in the pathogenesis of KOA.

  10. The sorting protein PACS-2 promotes ErbB signalling by regulating recycling of the metalloproteinase ADAM17

    PubMed Central

    Dombernowsky, Sarah Louise; Samsøe-Petersen, Jacob; Petersen, Camilla Hansson; Instrell, Rachael; Hedegaard, Anne-Mette Bornhardt; Thomas, Laurel; Atkins, Katelyn Mae; Auclair, Sylvain; Albrechtsen, Reidar; Mygind, Kasper Johansen; Fröhlich, Camilla; Howell, Michael; Parker, Peter; Thomas, Gary; Kveiborg, Marie

    2015-01-01

    The metalloproteinase ADAM17 activates ErbB signalling by releasing ligands from the cell surface, a key step underlying epithelial development, growth, and tumour progression. However, mechanisms acutely controlling ADAM17 cell-surface availability to modulate the extent of ErbB ligand release are poorly understood. Here, through a functional genome-wide siRNA screen, we identify the sorting protein PACS-2 as a regulator of ADAM17 trafficking and ErbB signalling. PACS-2 loss reduces ADAM17 cell-surface levels and ADAM17-dependent ErbB ligand shedding, without apparent effects on related proteases. PACS-2 co-localizes with ADAM17 on early endosomes and PACS-2 knockdown decreases the recycling and stability of internalized ADAM17. Hence, PACS-2 sustains ADAM17 cell-surface activity by diverting ADAM17 away from degradative pathways. Interestingly, Pacs2-deficient mice display significantly reduced levels of phosphorylated EGFR and intestinal proliferation. We suggest that this mechanism controlling ADAM17 cell-surface availability and EGFR signalling may play a role in intestinal homeostasis, with potential implications for cancer biology. PMID:26108729

  11. ADAM binding protein Eve-1 is required for ectodomain shedding of epidermal growth factor receptor ligands.

    PubMed

    Tanaka, Motonari; Nanba, Daisuke; Mori, Seiji; Shiba, Fumio; Ishiguro, Hiroshi; Yoshino, Koichiro; Matsuura, Nariaki; Higashiyama, Shigeki

    2004-10-01

    A disintegrin and metalloproteases (ADAMs) are implicated in the ectodomain shedding of epidermal growth factor receptor (EGFR) ligands in EGFR transactivation. However, the activation mechanisms of ADAMs remain elusive. To analyze the regulatory mechanisms of ADAM activation, we performed yeast two-hybrid screening using the cytoplasmic domain of ADAM12 as bait, and identified a protein that we designated Eve-1. Two cDNAs were cloned and characterized. They encode alternatively spliced isoforms of Eve-1, called Eve-1a and Eve-1b, that have four and five tandem Src homology 3 (SH3) domains in the carboxyl-terminal region, respectively, and seven proline-rich SH3 domain binding motifs in the amino-terminal region. The short forms of Eve-1, Eve-1c and Eve-1d, translated at Met-371 are human counterparts of mouse Sh3d19. Northern blot analysis demonstrated that Eve-1 is abundantly expressed in skeletal muscle and heart. Western blot analysis revealed the dominant production of Eve-1c in human cancer cell lines. Knockdown of Eve-1 by small interfering RNA in HT1080 cells reduced the shedding of proHB-EGF induced by angiotensin II and 12-O-tetradecanoylphorbol-13-acetate, as well as the shedding of pro-transforming growth factor-alpha, promphiregulin, and proepiregulin by 12-O-tetradecanoylphorbol-13-acetate, suggesting that Eve-1 plays a role in positively regulating the activity of ADAMs in the signaling of EGFR-ligand shedding.

  12. Epidermal growth factor (EGF) ligand release by substrate-specific a disintegrin and metalloproteases (ADAMs) involves different protein kinase C (PKC) isoenzymes depending on the stimulus.

    PubMed

    Dang, Michelle; Dubbin, Karen; D'Aiello, Antonio; Hartmann, Monika; Lodish, Harvey; Herrlich, Andreas

    2011-05-20

    The dysregulation of EGF family ligand cleavage has severe consequences for the developing as well as the adult organism. Therefore, their production is highly regulated. The limiting step is the ectodomain cleavage of membrane-bound precursors by one of several a disintegrin and metalloprotease (ADAM) metalloproteases, and understanding the regulation of cleavage is an important goal of current research. We have previously reported that in mouse lung epithelial cells, the pro-EGF ligands TGFα, neuregulin 1β (NRG), and heparin-binding EGF are differentially cleaved depending on the cleavage stimulus (Herrlich, A., Klinman, E., Fu, J., Sadegh, C., and Lodish, H. (2008) FASEB J.). In this study in mouse embryonic fibroblasts that lack different ADAMs, we show that induced cleavage of EGF ligands can involve the same substrate-specific metalloprotease but does require different stimulus-dependent signaling pathways. Cleavage was stimulated by phorbol ester (12-O-tetradecanoylphorbol-13-acetate (TPA), a mimic of diacylglycerol and PKC activator), hypertonic stress, lysophosphatidic acid (LPA)-induced G protein-coupled receptor activation, or by ionomycin-induced intracellular calcium release. Although ADAMs showed substrate preference (ADAM17, TGFα and heparin-binding EGF; and ADAM9, NRG), substrate cleavage differed substantially with the stimulus, and cleavage of the same substrate depended on the presence of different, sometimes multiple, PKC isoforms. For instance, classical PKC was required for TPA-induced but not hypertonic stress-induced cleavage of all EGF family ligands. Inhibition of PKCζ enhanced NRG release upon TPA stimulation, but it blocked NRG release in response to hypertonic stress. Our results suggest a model in which substantial regulation of ectodomain cleavage occurs not only on the metalloprotease level but also on the level of the substrate or of a third protein.

  13. The LGI1-ADAM22 protein complex directs synapse maturation through regulation of PSD-95 function.

    PubMed

    Lovero, Kathryn L; Fukata, Yuko; Granger, Adam J; Fukata, Masaki; Nicoll, Roger A

    2015-07-28

    Synapse development is coordinated by a number of transmembrane and secreted proteins that come together to form synaptic organizing complexes. Whereas a variety of synaptogenic proteins have been characterized, much less is understood about the molecular networks that support the maintenance and functional maturation of nascent synapses. Here, we demonstrate that leucine-rich, glioma-inactivated protein 1 (LGI1), a secreted protein previously shown to modulate synaptic AMPA receptors, is a paracrine signal released from pre- and postsynaptic neurons that acts specifically through a disintegrin and metalloproteinase protein 22 (ADAM22) to set postsynaptic strength. We go on to describe a novel role for ADAM22 in maintaining excitatory synapses through PSD-95/Dlg1/zo-1 (PDZ) domain interactions. Finally, we show that in the absence of LGI1, the mature synapse scaffolding protein PSD-95, but not the immature synapse scaffolding protein SAP102, is unable to modulate synaptic transmission. These results indicate that LGI1 and ADAM22 form an essential synaptic organizing complex that coordinates the maturation of excitatory synapses by regulating the functional incorporation of PSD-95.

  14. Regulation of Alpha-Secretase ADAM10 In vitro and In vivo: Genetic, Epigenetic, and Protein-Based Mechanisms

    PubMed Central

    Endres, Kristina; Deller, Thomas

    2017-01-01

    ADAM10 (A Disintegrin and Metalloproteinase 10) has been identified as the major physiological alpha-secretase in neurons, responsible for cleaving APP in a non-amyloidogenic manner. This cleavage results in the production of a neuroprotective APP-derived fragment, APPs-alpha, and an attenuated production of neurotoxic A-beta peptides. An increase in ADAM10 activity shifts the balance of APP processing toward APPs-alpha and protects the brain from amyloid deposition and disease. Thus, increasing ADAM10 activity has been proposed an attractive target for the treatment of neurodegenerative diseases and it appears to be timely to investigate the physiological mechanisms regulating ADAM10 expression. Therefore, in this article, we will (1) review reports on the physiological regulation of ADAM10 at the transcriptional level, by epigenetic factors, miRNAs and/or protein interactions, (2) describe conditions, which change ADAM10 expression in vitro and in vivo, (3) report how neuronal ADAM10 expression may be regulated in humans, and (4) discuss how this knowledge on the physiological and pathophysiological regulation of ADAM10 may help to preserve or restore brain function. PMID:28367112

  15. ADAM12 is expressed in the tumour vasculature and mediates ectodomain shedding of several membrane-anchored endothelial proteins.

    PubMed

    Fröhlich, Camilla; Klitgaard, Marie; Noer, Julie B; Kotzsch, Alexander; Nehammer, Camilla; Kronqvist, Pauliina; Berthelsen, Jens; Blobel, Carl; Kveiborg, Marie; Albrechtsen, Reidar; Wewer, Ulla M

    2013-05-15

    ADAM (a disintegrin and metalloproteinase) 12 is a metalloprotease implicated in cancer progression. ADAM12 can activate membrane-anchored proteins, such as sonic hedgehog, Delta-like 1 and certain epidermal growth factor receptor ligands, through a process called ectodomain shedding. We screened several membrane-anchored proteins to further dissect the substrate profile of ADAM12-mediated ectodomain shedding, and found shedding of five previously unreported substrates [Kitl1, VE-cadherin (vascular endothelial cadherin), Flk-1 (fetal liver kinase 1), Tie-2, and VCAM-1 (vascular cell adhesion molecule 1)], of which the latter four are specifically expressed by endothelial cells. We also observed that ADAM12 expression was increased in the tumour vasculature of infiltrating ductal carcinoma of the human breast as compared with little to no expression in normal breast tissue vasculature, suggesting a role for ADAM12 in tumour vessels. These results prompted us to further evaluate ADAM12-mediated shedding of two endothelial cell proteins, VE-cadherin and Tie-2. Endogenous ADAM12 expression was very low in cultured endothelial cells, but was significantly increased by cytokine stimulation. In parallel, the shed form of VE-cadherin was elevated in such cytokine-stimulated endothelial cells, and ADAM12 siRNA (small interfering RNA) knockdown reduced cytokine-induced shedding of VE-cadherin. In conclusion, the results of the present study demonstrate a role for ADAM12 in ectodomain shedding of several membrane-anchored endothelial proteins. We speculate that this process may have importance in tumour neovascularization or/and tumour cell extravasation.

  16. Scaffolded multiple cyclic peptide libraries for protein mimics by native chemical ligation.

    PubMed

    van de Langemheen, H; van Hoeke, M; Quarles van Ufford, H C; Kruijtzer, J A W; Liskamp, R M J

    2014-07-07

    The accessibility to collections, libraries and arrays of cyclic peptides is increasingly important since cyclic peptides may provide better mimics of the loop-like structures ubiquitously present in and - especially - on the surface of proteins. The next important step is the preparation of libraries of ensembles of scaffolded cyclic peptides, which upon screening may lead to promising protein mimics. Here we describe the synthesis of a tri-cysteine containing scaffold as well as the simultaneous native chemical ligation of three cyclic peptides thereby affording a clean library of multiple cyclic peptides on this scaffold, representing potential mimics of gp120. Members of this collection of protein mimics showed a decent inhibition of the gp120-CD4 interaction.

  17. Scaffold optimization in discontinuous epitope containing protein mimics of gp120 using smart libraries.

    PubMed

    Mulder, Gwenn E; Quarles van Ufford, H Linda C; van Ameijde, Jeroen; Brouwer, Arwin J; Kruijtzer, John A W; Liskamp, Rob M J

    2013-04-28

    A diversity of protein surface discontinuous epitope mimics is now rapidly and efficiently accessible. Despite the important role of protein-protein interactions involving discontinuous epitopes in a wide range of diseases, mimicry of discontinuous epitopes using peptide-based molecules remains a major challenge. Using copper(I) catalyzed azide-alkyne cycloaddition (CuAAC), we have developed a general and efficient method for the synthesis of collections of discontinuous epitope mimics. Up to three different cyclic peptides, representing discontinuous epitopes in HIV-gp120, were conjugated to a selection of scaffold molecules. Variation of the scaffold molecule, optimization of the ring size of the cyclic peptides and screening of the resulting libraries for successful protein mimics led to an HIV gp120 mimic with an IC50 value of 1.7 μM. The approach described here provides rapid and highly reproducible access to clean, smart libraries of very complex bio-molecular constructs representing protein mimics for use as synthetic vaccines and beyond.

  18. Circulating ADAM17 Level Reflects Disease Activity in Proteinase-3 ANCA-Associated Vasculitis.

    PubMed

    Bertram, Anna; Lovric, Svjetlana; Engel, Alissa; Beese, Michaela; Wyss, Kristin; Hertel, Barbara; Park, Joon-Keun; Becker, Jan U; Kegel, Johanna; Haller, Hermann; Haubitz, Marion; Kirsch, Torsten

    2015-11-01

    ANCA-associated vasculitides are characterized by inflammatory destruction of small vessels accompanied by enhanced cleavage of membrane-bound proteins. One of the main proteases responsible for ectodomain shedding is disintegrin and metalloproteinase domain-containing protein 17 (ADAM17). Given its potential role in aggravating vascular dysfunction, we examined the role of ADAM17 in active proteinase-3 (PR3)-positive ANCA-associated vasculitis (AAV). ADAM17 concentration was significantly increased in plasma samples from patients with active PR3-AAV compared with samples from patients in remission or from other controls with renal nonvascular diseases. Comparably, plasma levels of the ADAM17 substrate syndecan-1 were significantly enhanced in active AAV. We also observed that plasma-derived ADAM17 retained its specific proteolytic activity and was partly located on extracellular microparticles. Transcript levels of ADAM17 were increased in blood samples of patients with active AAV, but those of ADAM10 or tissue inhibitor of metalloproteinases 3, which inhibits ADAMs, were not. We also performed a microRNA (miR) screen and identified miR-634 as significantly upregulated in blood samples from patients with active AAV. In vitro, miR-634 mimics induced a proinflammatory phenotype in monocyte-derived macrophages, with enhanced expression and release of ADAM17 and IL-6. These data suggest that ADAM17 has a prominent role in AAV and might account for the vascular complications associated with this disease.

  19. Circulating ADAM17 Level Reflects Disease Activity in Proteinase-3 ANCA-Associated Vasculitis

    PubMed Central

    Bertram, Anna; Lovric, Svjetlana; Engel, Alissa; Beese, Michaela; Wyss, Kristin; Hertel, Barbara; Park, Joon-Keun; Becker, Jan U.; Kegel, Johanna; Haller, Hermann; Haubitz, Marion

    2015-01-01

    ANCA-associated vasculitides are characterized by inflammatory destruction of small vessels accompanied by enhanced cleavage of membrane-bound proteins. One of the main proteases responsible for ectodomain shedding is disintegrin and metalloproteinase domain-containing protein 17 (ADAM17). Given its potential role in aggravating vascular dysfunction, we examined the role of ADAM17 in active proteinase-3 (PR3)-positive ANCA-associated vasculitis (AAV). ADAM17 concentration was significantly increased in plasma samples from patients with active PR3-AAV compared with samples from patients in remission or from other controls with renal nonvascular diseases. Comparably, plasma levels of the ADAM17 substrate syndecan-1 were significantly enhanced in active AAV. We also observed that plasma-derived ADAM17 retained its specific proteolytic activity and was partly located on extracellular microparticles. Transcript levels of ADAM17 were increased in blood samples of patients with active AAV, but those of ADAM10 or tissue inhibitor of metalloproteinases 3, which inhibits ADAMs, were not. We also performed a microRNA (miR) screen and identified miR-634 as significantly upregulated in blood samples from patients with active AAV. In vitro, miR-634 mimics induced a proinflammatory phenotype in monocyte-derived macrophages, with enhanced expression and release of ADAM17 and IL-6. These data suggest that ADAM17 has a prominent role in AAV and might account for the vascular complications associated with this disease. PMID:25788529

  20. Peptide-Based Molecular Hydrogels as Supramolecular Protein Mimics.

    PubMed

    Singh, Nishant; Kumar, Mohit; Miravet, Juan F; Ulijn, Rein V; Escuder, Beatriu

    2017-01-23

    This Minireview concerns recent advances in the design, synthesis, and application of low molecular-weight peptidic hydrogelators. The sequence-specific combinations of amino acid side chain functionalities combined with hydrogen bonding of amide backbones and hydrophobic (aromatic) capping groups give these peptidic molecules the intrinsic tendency to self-assemble. The most prevalent designs include N-capped amino acid residues, bolamphiphilic peptides, and amphipathic peptides. Factors such as hydrophobic effects, the Hofmeister effect, and tunable ionization influence their aggregation properties. The self-assembly of simple bio-inspired building blocks into higher organized structures allows comparisons to be drawn with proteins and their complex functionalities, providing preliminary insights into complex biological functions and also enabling their application in a wide range of fields including catalysis, biomedical applications, and mimicry of natural dissipative systems. The Minireview is concluded by a short summary and outlook, highlighting the advances and steps required to bridge the gaps in the understanding of such systems.

  1. ADAM-10-Mediated N-cadherin Cleavage is Protein Kinase C-α–Dependent and Promotes Glioblastoma Cell Migration

    PubMed Central

    Kohutek, Zachary A.; diPierro, Charles G.; Redpath, Gerard T.; Hussaini, Isa M.

    2009-01-01

    Matrix metalloproteinases (MMPs) and the related ‘a disintegrin and metalloproteinases’ (ADAMs) promote tumorigenesis by cleaving extracellular matrix and protein substrates, including N-cadherin. While N-cadherin is thought to regulate cell adhesion, migration and invasion, its role has not been characterized in glioblastomas (GBMs). In this study, we investigated the expression and function of post-translational N-cadherin cleavage in GBM cells as well as its regulation by protein kinase C (PKC). N-cadherin cleavage occurred at a higher level in glioblastoma cells than in non-neoplastic astrocytes. Treatment with the PKC-activator phorbol 12-myristate 13-acetate (PMA) increased N-cadherin cleavage, which was reduced by pharmacological inhibitors and siRNA specific for ADAM-10 or PKC-α. Furthermore, treatment of GBM cells with PMA induced the translocation of ADAM-10 to the cell membrane, the site where N-cadherin was cleaved, and this translocation was significantly reduced by the PKC-α inhibitor Gö6976 or PKC-α shRNA. In functional studies, N-cadherin cleavage was required for GBM cell migration, as depletion of N-cadherin cleavage by N-cadherin siRNA, ADAM-10 siRNA, or a cleavage-site mutant N-cadherin, decreased GBM cell migration. Taken together, these results suggest that N-cadherin cleavage is regulated by a PKC-α-ADAM-10 cascade in GBM cells and may be involved in mediating GBM cell migration. PMID:19357285

  2. Fe-TAML encapsulated inside mesoporous silica nanoparticles as peroxidase mimic: femtomolar protein detection.

    PubMed

    Kumari, Sushma; Dhar, Basab B; Panda, Chakadola; Meena, Abhishek; Sen Gupta, Sayam

    2014-08-27

    Peroxidase, such as horseradish peroxidase (HRP), conjugated to antibodies are routinely used for the detection of proteins via an ELISA type assay in which a critical step is the catalytic signal amplification by the enzyme to generate a detectable signal. Synthesis of functional mimics of peroxidase enzyme that display catalytic activity which far exceeds the native enzyme is extremely important for the precise and accurate determination of very low quantities of proteins (fM and lower) that is necessary for early clinical diagnosis. Despite great advancements, analyzing proteins of very low abundance colorimetrically, a method that is most sought after since it requires no equipment for the analysis, still faces great challenges. Most reported HRP mimics that show catalytic activity greater than native enzyme (∼10-fold) are based on metal/metal-oxide nanoparticles such as Fe3O4. In this paper, we describe a second generation hybrid material developed by us in which approximately 25,000 alkyne tagged biuret modified Fe-tetraamido macrocyclic ligand (Fe-TAML), a very powerful small molecule synthetic HRP mimic, was covalently attached inside a 40 nm mesoporous silica nanoparticle (MSN). Biuret-modified Fe-TAMLs represent one of the best small molecule functional mimics of the enzyme HRP with reaction rates in water close to the native enzyme and operational stability (pH, ionic strength) far exceeding the natural enzyme. The catalytic activity of this hybrid material is around 1000-fold higher than that of natural HRP and 100-fold higher than that of most metal/metal oxide nanoparticle based HRP mimics reported to date. We also show that using antibody conjugates of this hybrid material it is possible to detect and, most importantly, quantify femtomolar quantities of proteins colorimetrically in an ELISA type assay. This represents at least 10-fold higher sensitivity than other colorimetric protein assays that have been reported using metal/metal oxide

  3. ADAM function in embryogenesis

    PubMed Central

    Alfandari, Dominique; McCusker, Catherine; Cousin, Hélène

    2009-01-01

    Cleavage of proteins inserted into the plasma membrane (shedding) is an essential process controlling many biological functions including cell signaling, cell adhesion and migration as well as proliferation and differentiation. ADAM surface metalloproteases have been shown to play an essential role in these processes. Gene inactivation during embryonic development have provided evidence of the central role of ADAM proteins in nematodes, flies, frogs, birds and mammals. The relative contribution of four subfamilies of ADAM proteins to developmental processes is the focus of this review. PMID:18935966

  4. ADAMs 10 and 17 Represent Differentially Regulated Components of a General Shedding Machinery for Membrane Proteins Such as Transforming Growth Factor α, L-Selectin, and Tumor Necrosis Factor α

    PubMed Central

    Le Gall, Sylvain M.; Bobé, Pierre; Reiss, Karina; Horiuchi, Keisuke; Niu, Xiao-Da; Lundell, Daniel; Gibb, David R.; Conrad, Daniel; Saftig, Paul

    2009-01-01

    Protein ectodomain shedding is a critical regulator of many membrane proteins, including epidermal growth factor receptor-ligands and tumor necrosis factor (TNF)-α, providing a strong incentive to define the responsible sheddases. Previous studies identified ADAM17 as principal sheddase for transforming growth factor (TGF)-α and heparin-binding epidermal growth factor, but Ca++ influx activated an additional sheddase for these epidermal growth factor receptor ligands in Adam17−/− cells. Here, we show that Ca++ influx and stimulation of the P2X7R signaling pathway activate ADAM10 as sheddase of many ADAM17 substrates in Adam17−/− fibroblasts and primary B cells. Importantly, although ADAM10 can shed all substrates of ADAM17 tested here in Adam17−/− cells, acute treatment of wild-type cells with a highly selective ADAM17 inhibitor (SP26) showed that ADAM17 is nevertheless the principal sheddase when both ADAMs 10 and 17 are present. However, chronic treatment of wild-type cells with SP26 promoted processing of ADAM17 substrates by ADAM10, thus generating conditions such as in Adam17−/− cells. These results have general implications for understanding the substrate selectivity of two major cellular sheddases, ADAMs 10 and 17. PMID:19158376

  5. Physiological functions of the amyloid precursor protein secretases ADAM10, BACE1, and presenilin.

    PubMed

    Prox, Johannes; Rittger, Andrea; Saftig, Paul

    2012-04-01

    Alzheimer's disease causing mutations in the amyloid precursor protein (APP) or in the Presenilin 1 (PS1) or Presenilin 2 (PS2) genes increase the production of amyloid peptides (Aβ) that precipitate in amyloid plaques. Since amyloid plaques are also a prominent feature of sporadic Alzheimer's disease (AD), abnormal proteolysis of APP and the generation of amyloid beta (Aβ) are key events in the pathogenesis of AD. The proteases (secretases) that cleave APP are therefore important therapeutic targets, both for the rare familial forms but likely also for the sporadic forms of AD. The identification and understanding of the (neuro)biological functions of the α-, β-, and presenilin/γ-secretase (complexes) is important for the development of drugs and the delineation of their associated side effects. The potential impact of this type of research exceeds the AD field since the function of these secretases are also linked to cellular pathways like ectodomain shedding of growth factors and regulated intramembrane proteolysis of receptors in developmental biology, tissue homeostasis, and tumorigenesis. The generation of mice deficient in presenilin 1, presenilin 2, the α-secretase ADAM10, and the β-secretases BACE1 and BACE2 were instrumental for the elucidation of the physiological functions of these proteases. Using these mouse models understanding how these secretases regulate amyloid peptide formation and how they exert their diverse biological functions could be significantly increased. This review attempts to summarize selected aspects of the current view of the multiple roles such proteases play in health and disease.

  6. Protocadherin-12 Cleavage Is a Regulated Process Mediated by ADAM10 Protein

    PubMed Central

    Bouillot, Stéphanie; Tillet, Emmanuelle; Carmona, Guillaume; Prandini, Marie-Hélène; Gauchez, Anne-Sophie; Hoffmann, Pascale; Alfaidy, Nadia; Cand, Francine; Huber, Philippe

    2011-01-01

    Protocadherins are a group of transmembrane proteins with homophilic binding activity, members of the cadherin superfamily. Apart from their role in adhesion, the cellular functions of protocadherins are essentially unknown. Protocadherin (PCDH)12 was previously identified in invasive trophoblasts and endothelial and mesangial cells in the mouse. Invalidation studies revealed that the protein was required for optimal placental development. In this article, we show that its human homolog is abundantly expressed in various trophoblast subtypes of the human placenta and at lower levels in endothelial cells. We demonstrate that PCDH12 is shed at high rates in vitro. The shedding mechanism depends on ADAM10 and results in reduced cellular adhesion in a cell migration assay. PCDH12 is subsequently cleaved by the γ-secretase complex, and its cytoplasmic domain is rapidly degraded by the proteasome. PCDH12 shedding is regulated by interlinked intracellular pathways, including those involving protein kinase C, PI3K, and cAMP, that either increase or inhibit cleavage. In endothelial cells, VEGF, prostaglandin E2, or histamine regulates PCDH12 shedding. The extracellular domain of PCDH12 was also detected in human serum and urine, thus providing evidence of PCDH12 shedding in vivo. Importantly, we observed an increase in circulating PCDH12 in pregnant women who later developed a pre-eclampsia, a frequent pregnancy syndrome and a major cause of maternal and fetal morbidity and mortality. In conclusion, we speculate that, like in mice, PCDH12 may play an important role in human placental development and that proteolytic cleavage in response to external factors, such as cytokines and pathological settings, regulates its activity. PMID:21402705

  7. Structure of Ocr from bacteriophage T7, a protein that mimics B-form DNA.

    PubMed

    Walkinshaw, M D; Taylor, P; Sturrock, S S; Atanasiu, C; Berge, T; Henderson, R M; Edwardson, J M; Dryden, D T F

    2002-01-01

    We have solved, by X-ray crystallography to a resolution of 1.8 A, the structure of a protein capable of mimicking approximately 20 base pairs of B-form DNA. This ocr protein, encoded by gene 0.3 of bacteriophage T7, mimics the size and shape of a bent DNA molecule and the arrangement of negative charges along the phosphate backbone of B-form DNA. We also demonstrate that ocr is an efficient inhibitor in vivo of all known families of the complex type I DNA restriction enzymes. Using atomic force microscopy, we have also observed that type I enzymes induce a bend in DNA of similar magnitude to the bend in the ocr molecule. This first structure of an antirestriction protein demonstrates the construction of structural mimetics of long segments of B-form DNA.

  8. Preorganized Peptide Scaffolds as Mimics of Phosphorylated Proteins Binding Sites with a High Affinity for Uranyl.

    PubMed

    Starck, Matthieu; Sisommay, Nathalie; Laporte, Fanny A; Oros, Stéphane; Lebrun, Colette; Delangle, Pascale

    2015-12-07

    Cyclic peptides with two phosphoserines and two glutamic acids were developed to mimic high-affinity binding sites for uranyl found in proteins such as osteopontin, which is believed to be a privileged target of this ion in vivo. These peptides adopt a β-sheet structure that allows the coordination of the latter amino acid side chains in the equatorial plane of the dioxo uranyl cation. Complementary spectroscopic and analytical methods revealed that these cyclic peptides are efficient uranyl chelating peptides with a large contribution from the phosphorylated residues. The conditional affinity constants were measured by following fluorescence tryptophan quenching and are larger than 10(10) at physiological pH. These compounds are therefore promising models for understanding uranyl chelation by proteins, which is relevant to this actinide ion toxicity.

  9. Amyloid β-sheet mimics that antagonize protein aggregation and reduce amyloid toxicity

    NASA Astrophysics Data System (ADS)

    Cheng, Pin-Nan; Liu, Cong; Zhao, Minglei; Eisenberg, David; Nowick, James S.

    2012-11-01

    The amyloid protein aggregation associated with diseases such as Alzheimer's, Parkinson's and type II diabetes (among many others) features a bewildering variety of β-sheet-rich structures in transition from native proteins to ordered oligomers and fibres. The variation in the amino-acid sequences of the β-structures presents a challenge to developing a model system of β-sheets for the study of various amyloid aggregates. Here, we introduce a family of robust β-sheet macrocycles that can serve as a platform to display a variety of heptapeptide sequences from different amyloid proteins. We have tailored these amyloid β-sheet mimics (ABSMs) to antagonize the aggregation of various amyloid proteins, thereby reducing the toxicity of amyloid aggregates. We describe the structures and inhibitory properties of ABSMs containing amyloidogenic peptides from the amyloid-β peptide associated with Alzheimer's disease, β2-microglobulin associated with dialysis-related amyloidosis, α-synuclein associated with Parkinson's disease, islet amyloid polypeptide associated with type II diabetes, human and yeast prion proteins, and Tau, which forms neurofibrillary tangles.

  10. Methylation of a histone mimic within the histone methyltransferase G9a regulates protein complex assembly.

    PubMed

    Sampath, Srihari C; Marazzi, Ivan; Yap, Kyoko L; Sampath, Srinath C; Krutchinsky, Andrew N; Mecklenbräuker, Ingrid; Viale, Agnes; Rudensky, Eugene; Zhou, Ming-Ming; Chait, Brian T; Tarakhovsky, Alexander

    2007-08-17

    Epigenetic gene silencing in eukaryotes is regulated in part by lysine methylation of the core histone proteins. While histone lysine methylation is known to control gene expression through the recruitment of modification-specific effector proteins, it remains unknown whether nonhistone chromatin proteins are targets for similar modification-recognition systems. Here we show that the histone H3 methyltransferase G9a contains a conserved methylation motif with marked sequence similarity to H3 itself. As with methylation of H3 lysine 9, autocatalytic G9a methylation is necessary and sufficient to mediate in vivo interaction with the epigenetic regulator heterochromatin protein 1 (HP1), and this methyl-dependent interaction can be reversed by adjacent G9a phosphorylation. NMR analysis indicates that the HP1 chromodomain recognizes methyl-G9a through a binding mode similar to that used in recognition of methyl-H3K9, demonstrating that the chromodomain functions as a generalized methyl-lysine binding module. These data reveal histone-like modification cassettes - or "histone mimics" - as a distinct class of nonhistone methylation targets and directly extend the principles of the histone code to the regulation of nonhistone proteins.

  11. ADAM12 — EDRN Public Portal

    Cancer.gov

    ADAM12 is a member of the ADAM (a disintegrin and metalloprotease) protein family. ADAM family members are membrane-anchored proteins structurally related to snake venom disintegrins, and have been implicated in a variety of biological processes involving cell-cell and cell-matrix interactions. ADAM12 has two alternatively spliced transcripts: a shorter secreted form and a longer membrane-bound form. The shorter form is found to stimulate myogenesis.

  12. MD-simulations of Beta-Amyloid Protein Insertion Efficiency and Kinetics into Neuronal Membrane Mimics

    NASA Astrophysics Data System (ADS)

    Qiu, Liming; Buie, Creighton; Vaughn, Mark; Cheng, Kwan

    2011-03-01

    Early interaction events of beta-amyloid (A β) peptides with the neuronal membranes play a key role in the pathogenesis of Alzheimer's disease. We have used all-atom MD simulations to study the protein insertion efficiency and kinetics of monomeric A β40 and A β42 into phosphatidylcholine lipid bilayers (PC) with and without 40 mole% cholesterol (CHOL) that mimic the cholesterol-enriched and depleted lipid nanodomains of the neuronal plasma membranes. Independent replicates of 200-ns simulations of each protein pre-inserted in the upper lipid layer were generated. In PC bilayers, only 25% of A β40 and 50% of A β42 in the replicates showed complete insertion into the lower lipid layer, whereas the percentages increased to 50% and 100%, respectively, in PC/CHOL bilayers, providing evidence that cholesterol improves the protein insertion efficiency into the bilayers. The rate of protein insertion was proportional to the hydrophobic, transmembrane helix length of the inserted peptide and depended on the cholesterol content. We propose that the lysine snorkeling and C-terminus anchoring of A β to the PC headgroups at the upper and lower lipid/water interfaces represent the dual-transmembrane stabilization mechanisms of A β in the neuronal membrane domains.

  13. ADAM17/EGFR axis promotes transglutaminase-dependent skin barrier formation through phosholipase C γ1 and protein kinase C pathways

    PubMed Central

    Wolf , Cristina; Qian, Yawen; Brooke, Matthew A.; Kelsell, David P.; Franzke, Claus-Werner

    2016-01-01

    The vitally important skin barrier is formed by extensive cross-linking activity of transglutaminases (TGs) during terminal epidermal differentiation. We have previously shown that epidermal deficiency of a disintegrin and metalloproteinase 17 (ADAM17), the principal EGFR ligand sheddase, results in postnatal skin barrier defects in mice due to impeded TG activity. However, the mechanism by which ADAM17/EGFR signalling maintains TG activity during epidermal differentiation remains elusive. Here we demonstrate that ADAM17-dependent EGFR signalling promotes TG activity in keratinocytes committed to terminal differentiation by direct induction of TG1 expression. Restored TG1 expression of EGF-stimulated differentiated Adam17−/− keratinocytes was strongly repressed by inhibitors for PLCγ1 or protein kinase C (PKC) pathways, while treatment with the PKC stimulator 12-O-tetradecanoylphorbol-13-acetate restored TG activity in the epidermis of keratinocyte-specific Adam17−/− (AD17ΔKC) mice. Further investigations emphasized the expression of PKCη, a mediator of TGM1 transcription, to be sensitive to EGFR activation. In agreement, topical skin application of cholesterol sulfate, an activator of PKCη, significantly improved TG activity in epidermis of AD17ΔKC mice. Our results suggest ADAM17/EGFR-driven PLCγ1 and PKC pathways as important promoters of TG1 expression during terminal keratinocyte differentiation. These findings may help to identify new therapeutic targets for inflammatory skin diseases related to epidermal barrier defects. PMID:28004780

  14. The Role of ADAM9 in Tumor-Stromal Interactions in Breast Cancer

    DTIC Science & Technology

    2010-04-01

    ADAM family members in cancer. ADAM12 is expressed in carcinoma and promotes breast cancer progression by inducing the apoptosis of surrounding...stromal cells (13). Consequently, ADAM12 protein levels correlate with advanced breast cancer (14, 15). In contrast, the disintegrin domain of ADAM15...subgroup of ADAMs that also contains ADAM12 and ADAM15 (18). The ADAM9 metalloprotease activity cleaves heparin-binding epidermal growth factor (HB

  15. Single honeybee silk protein mimics properties of multi-protein silk.

    PubMed

    Sutherland, Tara D; Church, Jeffrey S; Hu, Xiao; Huson, Mickey G; Kaplan, David L; Weisman, Sarah

    2011-02-02

    Honeybee silk is composed of four fibrous proteins that, unlike other silks, are readily synthesized at full-length and high yield. The four silk genes have been conserved for over 150 million years in all investigated bee, ant and hornet species, implying a distinct functional role for each protein. However, the amino acid composition and molecular architecture of the proteins are similar, suggesting functional redundancy. In this study we compare materials generated from a single honeybee silk protein to materials containing all four recombinant proteins or to natural honeybee silk. We analyse solution conformation by dynamic light scattering and circular dichroism, solid state structure by Fourier Transform Infrared spectroscopy and Raman spectroscopy, and fiber tensile properties by stress-strain analysis. The results demonstrate that fibers artificially generated from a single recombinant silk protein can reproduce the structural and mechanical properties of the natural silk. The importance of the four protein complex found in natural silk may lie in biological silk storage or hierarchical self-assembly. The finding that the functional properties of the mature material can be achieved with a single protein greatly simplifies the route to production for artificial honeybee silk.

  16. Expanding The Scope Of Oligo-pyrrolinone-pyrrolidines As Protein-protein Interface Mimics

    PubMed Central

    Raghuraman, Arjun; Xin, Dongyue; Perez, Lisa M.; Burgess, Kevin

    2013-01-01

    Oligo-pyrrolinone-pyrrolidines (generic structure 1) have the potential to interfere with protein-protein interactions (PPIs), but to reduce this to practice it is necessary to be able to synthesize these structures with a variety of different side-chains corresponding to genetically encoded proteins. This paper describes expansion of the synthetic scope of 1, the difficulties encountered in this process, particularly issues with epimerization and slow coupling rates, and methods to overcome them. Finally, spectroscopic and physicochemical properties as well as proteolytic stabilities of molecules in this series were measured; these data highlight the suitability of oligo-pyrrolinone-pyrrolidines for the development of pharmacological probes or pharmaceutical leads. PMID:23654284

  17. Designed ankyrin repeat proteins: a new approach to mimic complex antigens for diagnostic purposes?

    PubMed

    Hausammann, Stefanie; Vogel, Monique; Kremer Hovinga, Johanna A; Lacroix-Desmazes, Sebastien; Stadler, Beda M; Horn, Michael P

    2013-01-01

    Inhibitory antibodies directed against coagulation factor VIII (FVIII) can be found in patients with acquired and congenital hemophilia A. Such FVIII-inhibiting antibodies are routinely detected by the functional Bethesda Assay. However, this assay has a low sensitivity and shows a high inter-laboratory variability. Another method to detect antibodies recognizing FVIII is ELISA, but this test does not allow the distinction between inhibitory and non-inhibitory antibodies. Therefore, we aimed at replacing the intricate antigen FVIII by Designed Ankyrin Repeat Proteins (DARPins) mimicking the epitopes of FVIII inhibitors. As a model we used the well-described inhibitory human monoclonal anti-FVIII antibody, Bo2C11, for the selection on DARPin libraries. Two DARPins were selected binding to the antigen-binding site of Bo2C11, which mimic thus a functional epitope on FVIII. These DARPins inhibited the binding of the antibody to its antigen and restored FVIII activity as determined in the Bethesda assay. Furthermore, the specific DARPins were able to recognize the target antibody in human plasma and could therefore be used to test for the presence of Bo2C11-like antibodies in a large set of hemophilia A patients. These data suggest, that our approach might be used to isolate epitopes from different sets of anti-FVIII antibodies in order to develop an ELISA-based screening assay allowing the distinction of inhibitory and non-inhibitory anti-FVIII antibodies according to their antibody signatures.

  18. Molecular recognition of oxygen by protein mimics: dynamics on the femtosecond to microsecond time scale.

    PubMed

    Zou, Shouzhong; Baskin, J Spencer; Zewail, Ahmed H

    2002-07-23

    Molecular recognition by biological macromolecules involves many elementary steps, usually convoluted by diffusion processes. Here we report studies of the dynamics, from the femtosecond to the microsecond time scale, of the different elementary processes involved in the bimolecular recognition of a protein mimic, cobalt picket-fence porphyrin, with varying oxygen concentration at controlled temperatures. Electron transfer, bond breakage, and thermal "on" (recombination) and "off" (dissociation) reactions are the different processes involved. The reaction on-rate is 30 to 60 times smaller than that calculated from standard Smoluchowski theory. Introducing a two-step recognition model, with reversibility being part of both steps, removes the discrepancy and provides consistency for the reported thermodynamics, kinetics, and dynamics. The transient intermediates are configurations defined by the contact between oxygen (diatomic) and the picket-fence porphyrin (macromolecule). This intermediate is critical in the description of the potential energy landscape but, as shown here, both enthalpic and entropic contributions to the free energy are important. In the recognition process, the net entropy decrease is -33 cal mol(-1) K(-1); Delta H is -13.4 kcal mol(-1).

  19. Breast cancer-associated mutations in metalloprotease disintegrin ADAM12 interfere with the intracellular trafficking and processing of the protein.

    PubMed

    Dyczynska, Emilia; Syta, Emilia; Sun, Danqiong; Zolkiewska, Anna

    2008-06-01

    ADAM12 has recently emerged as a Candidate Cancer Gene in a comprehensive genetic analysis of human breast cancers. Three somatic mutations in ADAM12 were observed at significant frequencies in breast cancers: D301H, G479E and L792F. The first 2 of these mutations involve highly conserved residues in ADAM12, and our computational sequence analysis confirms that they may be cancer-related. We show that the corresponding mutations in mouse ADAM12 inhibit the proteolytic processing and activation of ADAM12 in NIH3T3, COS-7, CHO-K1 cells and in MCF-7 breast cancer cells. The D/H and G/E ADAM12 mutants exert a dominant-negative effect on the processing of the wild-type ADAM12. Immunofluorescence analysis and cell surface biotinylation experiments demonstrate that the D/H and G/E mutants are retained inside the cell and are not transported to the cell surface. Consequently, the D/H and G/E mutants, unlike the wild-type ADAM12, are not capable of shedding Delta-like l, a ligand for Notch receptor, at the cell surface, or of stimulating cell migration. Our results suggest that the breast cancer-associated mutations interfere with the intracellular trafficking of ADAM12 and result in loss of the functional ADAM12 at the cell surface.

  20. Lysine pyrrolation is a naturally-occurring covalent modification involved in the production of DNA mimic proteins.

    PubMed

    Miyashita, Hiroaki; Chikazawa, Miho; Otaki, Natsuki; Hioki, Yusuke; Shimozu, Yuki; Nakashima, Fumie; Shibata, Takahiro; Hagihara, Yoshihisa; Maruyama, Shoichi; Matsumi, Noriyoshi; Uchida, Koji

    2014-06-18

    Covalent modification of proteins exerts significant effects on their chemical properties and has important functional and regulatory consequences. We now report the identification and verification of an electrically-active form of modified proteins recognized by a group of small molecules commonly used to interact with DNA. This previously unreported property of proteins was initially discovered when the γ-ketoaldehydes were identified as a source of the proteins stained by the DNA intercalators. Using 1,4-butanedial, the simplest γ-ketoaldehyde, we characterized the structural and chemical criteria governing the recognition of the modified proteins by the DNA intercalators and identified N(ε)-pyrrolelysine as a key adduct. Unexpectedly, the pyrrolation conferred an electronegativity and electronic properties on the proteins that potentially constitute an electrical mimic to the DNA. In addition, we found that the pyrrolated proteins indeed triggered an autoimmune response and that the production of specific antibodies against the pyrrolated proteins was accelerated in human systemic lupus erythematosus. These findings and the apparent high abundance of N(ε)-pyrrolelysine in vivo suggest that protein pyrrolation could be an endogenous source of DNA mimic proteins, providing a possible link connecting protein turnover and immune disorders.

  1. Determination of the Proteolytic Cleavage Sites of the Amyloid Precursor-Like Protein 2 by the Proteases ADAM10, BACE1 and γ-Secretase

    PubMed Central

    Hogl, Sebastian; Kuhn, Peer-Hendrik; Colombo, Alessio; Lichtenthaler, Stefan F.

    2011-01-01

    Regulated intramembrane proteolysis of the amyloid precursor protein (APP) by the protease activities α-, β- and γ-secretase controls the generation of the neurotoxic amyloid β peptide. APLP2, the amyloid precursor-like protein 2, is a homolog of APP, which shows functional overlap with APP, but lacks an amyloid β domain. Compared to APP, less is known about the proteolytic processing of APLP2, in particular in neurons, and the cleavage sites have not yet been determined. APLP2 is cleaved by the β-secretase BACE1 and additionally by an α-secretase activity. The two metalloproteases ADAM10 and ADAM17 have been suggested as candidate APLP2 α-secretases in cell lines. Here, we used RNA interference and found that ADAM10, but not ADAM17, is required for the constitutive α-secretase cleavage of APLP2 in HEK293 and SH-SY5Y cells. Likewise, in primary murine neurons knock-down of ADAM10 suppressed APLP2 α-secretase cleavage. Using mass spectrometry we determined the proteolytic cleavage sites in the APLP2 sequence. ADAM10 was found to cleave APLP2 after arginine 670, whereas BACE1 cleaves after leucine 659. Both cleavage sites are located in close proximity to the membrane. γ-secretase cleavage was found to occur at different peptide bonds between alanine 694 and valine 700, which is close to the N-terminus of the predicted APLP2 transmembrane domain. Determination of the APLP2 cleavage sites enables functional studies of the different APLP2 ectodomain fragments and the production of cleavage-site specific antibodies for APLP2, which may be used for biomarker development. PMID:21695060

  2. Identification of ADAM10 and ADAM17 with potential roles in the spermatogenesis of the Chinese mitten crab, Eriocheir sinensis.

    PubMed

    Li, Qing; Xie, Jing; He, Lin; Wang, Yuanli; Duan, Zelin; Yang, Hongdan; Wang, Qun

    2015-05-10

    The ADAM (a disintegrin and metalloprotease) family plays an important role in sperm and egg fusion, development, inflammation, adhesion and migration. ADAM10 and ADAM17 are involved in the spermatogenesis. To better understand the role of ADAM10 and ADAM17 in the Chinese mitten crab, Eriocheir sinensis, the full-length cDNAs of ADAM10 and ADAM17 were cloned, and named Es-ADAM10 and Es-ADAM17, respectively. Sequence and structural analysis showed that Es-ADAM10 and Es-ADAM17 have the typical structure of the ADAM family. Quantitative real-time reverse transcription polymerase chain reaction analysis showed that Es-ADAM10 and Es-ADAM17 mRNAs were distributed in the heart, hepatopancreas, intestines, brain, muscle, thoracic ganglia, hemolymph, stomach, testis, ovary, gill and accessory gland. Both mRNAs were highly expressed in the muscles, and relatively high in the testis, ovary and accessory gland. In addition, the Es-ADAM17 mRNA level was detected in every stage of testis development, being relatively high from July to September, the lowest during October and November, increasing from December to January, and reached a peak in January. By contrast, the expression of Es-ADAM10 mRNA was constant during testis development. Immunofluorescence further showed that Es-ADAM10 and Es-ADAM17 proteins were present in the cytoplasm and cytomembrane of spermatocytes, and both detected in the sperm. Furthermore, etoposide induced upregulation of Es-ADAM17 and Es-ADAM10 at both the mRNA and protein levels. This study first showed that Es-ADAM10 and Es-ADAM17 were also involved in the spermatogenesis and mainly participated in the later germ cell apoptosis in E. sinensis.

  3. Differential Surface Expression of ADAM10 and ADAM17 on Human T Lymphocytes and Tumor Cells

    PubMed Central

    Kabelitz, Dieter; Janssen, Ottmar

    2013-01-01

    A disintegrin and metalloproteases (ADAMs) have been implicated in many processes controlling organismic development and integrity. Important substrates of ADAM proteases include growth factors, cytokines and their receptors and adhesion proteins. The inducible but irreversible cleavage of their substrates alters cell-cell communication and signaling. The crucial role of ADAM proteases (e.g. ADAM10 and 17) for mammalian development became evident from respective knockout mice, that displayed pre- or perinatal lethality with severe defects in many organs and tissues. Although many substrates for these two ADAM proteases were identified over the last decade, the regulation of their surface appearance, their enzymatic activity and their substrate specificity are still not well understood. We therefore analyzed the constitutive and inducible surface expression of ADAM10 and ADAM17 on a variety of human T cell and tumor cell lines. We demonstrate that ADAM10 is constitutively present at comparably high levels on the majority of the tested cell types. Stimulation with phorbol ester and calcium ionophore does not significantly alter the amount of surface ADAM10, except for a slight down-regulation from T cell blasts. Using FasL shedding as a readout for ADAM10 activity, we show that PKC activation and calcium mobilization are both prerequisite for activation of ADAM10 resulting in a production of soluble FasL. In contrast to ADAM10, the close relative ADAM17 is detected at only low levels on unstimulated cells. ADAM17 surface expression on T cell blasts is rapidly induced by stimulation. Since this inducible mobilization of ADAM17 is sensitive to inhibitors of actin filament formation, we propose that ADAM17 but not ADAM10 is prestored in a subcellular compartment that is transported to the cell surface in an activation- and actin-dependent manner. PMID:24130797

  4. Increased expression of ADAM12 and ADAM17 genes in laser-capture microdissected breast cancers and correlations with clinical and pathological characteristics.

    PubMed

    Narita, Diana; Seclaman, Edward; Ursoniu, Sorin; Anghel, Andrei

    2012-02-01

    ADAMs (a desintegrin and metalloprotease) are transmembrane glycoproteins involved in cell growth, differentiation, motility, and respectively, tumor growth and progression. Our aim was to evaluate ADAM12 spliced variants (ADAM12L - long membrane-bound and ADAM12S - secreted-short variant) and ADAM17 genes expression in breast cancers and to correlate their level of expression with clinical and pathological characteristics. Expression of ADAMs was analyzed using quantitative reverse-transcription polymerase chain reaction in laser-capture microdissected specimens of breast cancers and corresponding non-neoplastic breast tissues from 92 patients. The proteins' expression was confirmed by immunohistochemistry. Significantly elevated amounts of ADAM12L, ADAM12S and ADAM17 transcripts were found in malignant breast cells compared with normal breast tissue and both ADAMs proteins showed moderate to strong immunoexpression in tumor cells and peritumoral fibroblasts. ADAM12L and ADAM12S expressions were correlated with age, younger patients having higher expression of ADAM12L and ADAM12S; ductal cancers had higher expression of ADAM12L compared with lobular types, whereas ADAM12S was higher expressed in lobular cancers; higher expressions were found for both ADAM12 and ADAM17 in HER2/neu positive and highly proliferative cancers. High-grade cancers showed significantly increased expression of ADAM17. Our study on laser-capture microdissected specimens confers motivation for future work on development of ADAM-selective inhibitors for treatment of breast cancers.

  5. ERK1/2 Mediate Wounding- and G-protein-Coupled Receptor Ligands–Induced EGFR Activation via Regulating ADAM17 and HB-EGF Shedding

    PubMed Central

    Yin, Jia; Yu, Fu-Shin X.

    2013-01-01

    Purpose Previous studies have shown that wounding of human corneal epithelial cells (HCECs) results in the release of G-protein-coupled receptor ligands such as ATP and lysophosphatidic acid (LPA), which in turn transactivate epidermal growth factor (EGF) receptor (EGFR) through ectodomain shedding of heparin-binding EGF-like growth factor (HB-EGF). In the present study, the role of extracellular signal-regulated kinases 1/2 (ERK1/2) in regulating EGFR transactivation was investigated. Methods SV40-immortalized HCECs were wounded or stimulated with ATP and LPA. EGFR and ADAM17 activation was analyzed by immunoprecipitation followed by Western blot analysis with phospho-tyrosine or phospho-serine antibodies, respectively. Phosphorylation of ERK and AKT was analyzed by Western blot analysis. HB-EGF shedding was assessed by measuring the release of alkaline phosphatase (AP) in a stably transfected human corneal epithelial (THCE) cell line expressing HB-EGF-AP. ADAM17 and ERK interaction was determined by coimmunoprecipitation. Results Early, but not late, ERK1/2 phosphorylation in response to wounding, LPA, and ATP was EGFR independent, but sensitive to the inhibitors of calcium influx, protein kinase C and Src kinase. Wounding-, LPA-, and ATP-induced HB-EGF shedding and EGFR activation were attenuated by the MAPK/ERK kinase (MEK) inhibitors PD98059 and U0126, as well as by ADAM10 and -17 inhibitors. ADAM17 was found to be physically associated with active ERK and phosphorylated at serine residues in an ERK-dependent manner in wounded cells. Conclusions Taken together, our data suggest that in addition to functioning as an EGFR downstream effector, ERK1/2 also mediates ADAM-dependent HB-EGF shedding and subsequent EGFR transactivation in response to a variety of stimuli, including wounding and GPCR ligands. PMID:18658095

  6. An amphiphilic selenide catalyst behaves like a hybrid mimic of protein disulfide isomerase and glutathione peroxidase 7.

    PubMed

    Arai, Kenta; Moriai, Kenji; Ogawa, Akinobu; Iwaoka, Michio

    2014-12-01

    Protein disulfide isomerase (PDI) and glutathione peroxidase 7 (GPx7) cooperatively promote the oxidative folding of disulfide (SS)-containing proteins in endoplasmic reticulum by recognizing the nascent proteins to convert them into the native folds by means of SS formation and SS isomerization and by catalyzing reoxidation of reduced PDI with H2O2, respectively. In this study, new amphiphilic selenides with a long-chain alkyl group were designed as hybrid mimics of PDI and GPx7 and were applied to the refolding of reduced hen egg-white lysozyme (HEL-R). Competitive SS formation at pH 4 using HEL-R and glutathione (GSH) in the presence of the selenide catalyst and H2O2 showed that the amphiphilic selenides can preferentially catalyze SS formation of HEL-R, probably on account of hydrophobic interactions between the protein and the catalyst. In contrast, simple water-soluble selenides did not exhibit such behavior. In addition, when the pH of the solution was adjusted to 8.5 after the SS formation, surviving GSH promoted the SS isomerization of misfolded HEL to recover the native SS linkages. Thus, the amphiphilic selenides designed here could mimic the function of the PDI-GPx7 system. The combination of a water-soluble selenide and a long-chain alkyl group would be a useful motif in designing medicines for both protein misfolding diseases and antioxidant therapy.

  7. A library of MiMICs allows tagging of genes and reversible, spatial and temporal knockdown of proteins in Drosophila.

    PubMed

    Nagarkar-Jaiswal, Sonal; Lee, Pei-Tseng; Campbell, Megan E; Chen, Kuchuan; Anguiano-Zarate, Stephanie; Gutierrez, Manuel Cantu; Busby, Theodore; Lin, Wen-Wen; He, Yuchun; Schulze, Karen L; Booth, Benjamin W; Evans-Holm, Martha; Venken, Koen J T; Levis, Robert W; Spradling, Allan C; Hoskins, Roger A; Bellen, Hugo J

    2015-03-31

    Here, we document a collection of ∼7434 MiMIC (Minos Mediated Integration Cassette) insertions of which 2854 are inserted in coding introns. They allowed us to create a library of 400 GFP-tagged genes. We show that 72% of internally tagged proteins are functional, and that more than 90% can be imaged in unfixed tissues. Moreover, the tagged mRNAs can be knocked down by RNAi against GFP (iGFPi), and the tagged proteins can be efficiently knocked down by deGradFP technology. The phenotypes associated with RNA and protein knockdown typically correspond to severe loss of function or null mutant phenotypes. Finally, we demonstrate reversible, spatial, and temporal knockdown of tagged proteins in larvae and adult flies. This new strategy and collection of strains allows unprecedented in vivo manipulations in flies for many genes. These strategies will likely extend to vertebrates.

  8. A library of MiMICs allows tagging of genes and reversible, spatial and temporal knockdown of proteins in Drosophila

    SciTech Connect

    Nagarkar-Jaiswal, Sonal; Lee, Pei-Tseng; Campbell, Megan E.; Chen, Kuchuan; Anguiano-Zarate, Stephanie; Cantu Gutierrez, Manuel; Busby, Theodore; Lin, Wen-Wen; He, Yuchun; Schulze, Karen L.; Booth, Benjamin W.; Evans-Holm, Martha; Venken, Koen J.T.; Levis, Robert W.; Spradling, Allan C.; Hoskins, Roger A.; Bellen, Hugo J.

    2015-03-31

    Here, we document a collection of ~7434 MiMIC (Minos Mediated Integration Cassette) insertions of which 2854 are inserted in coding introns. They allowed us to create a library of 400 GFP-tagged genes. We show that 72% of internally tagged proteins are functional, and that more than 90% can be imaged in unfixed tissues. Moreover, the tagged mRNAs can be knocked down by RNAi against GFP (iGFPi), and the tagged proteins can be efficiently knocked down by deGradFP technology. The phenotypes associated with RNA and protein knockdown typically correspond to severe loss of function or null mutant phenotypes. Finally, we demonstrate reversible, spatial, and temporal knockdown of tagged proteins in larvae and adult flies. This new strategy and collection of strains allows unprecedented in vivo manipulations in flies for many genes. These strategies will likely extend to vertebrates.

  9. A library of MiMICs allows tagging of genes and reversible, spatial and temporal knockdown of proteins in Drosophila

    DOE PAGES

    Nagarkar-Jaiswal, Sonal; Lee, Pei-Tseng; Campbell, Megan E.; ...

    2015-03-31

    Here, we document a collection of ~7434 MiMIC (Minos Mediated Integration Cassette) insertions of which 2854 are inserted in coding introns. They allowed us to create a library of 400 GFP-tagged genes. We show that 72% of internally tagged proteins are functional, and that more than 90% can be imaged in unfixed tissues. Moreover, the tagged mRNAs can be knocked down by RNAi against GFP (iGFPi), and the tagged proteins can be efficiently knocked down by deGradFP technology. The phenotypes associated with RNA and protein knockdown typically correspond to severe loss of function or null mutant phenotypes. Finally, we demonstratemore » reversible, spatial, and temporal knockdown of tagged proteins in larvae and adult flies. This new strategy and collection of strains allows unprecedented in vivo manipulations in flies for many genes. These strategies will likely extend to vertebrates.« less

  10. Simulation of carbohydrate-protein interactions: Computer-aided design of a second generation GM1 mimic

    NASA Astrophysics Data System (ADS)

    Bernardi, Anna; Galgano, Marta; Belvisi, Laura; Colombo, Giorgio

    2001-02-01

    The oligosaccharide of ganglioside GM1 [Gal β1-3GalNAc β1-4(NeuAc α2-3)Gal β1-4Glc β1-1Cer] is the cellular target of two bacterial enterotoxins: the cholera toxin (CT) and the heat-labile toxin of E.coli (LT). We recently reported that the pseudosaccharide 2[Gal β1-3GalNAc β1-4(NeuAc α2-3)DCCHD] is a high-affinity ligand for CT, and thus a functional mimic of GM1 (Bernardi, A., Checchia, A., Brocca, P., Sonnino, S. and Zuccotto, F., J. Am. Chem. Soc., 121 (1999) 2032-2036). In this paper we describe the design of a second-generation mimic, formally obtained from 2 by inverting the configuration of a single stereocenter, thus transforming a N-acetyl galactosamine into a N-acetyl glucosamine. The design process involved modeling of the free ligand and its LT complex, followed by qualitative and quantitative comparison with the corresponding structures of 2. The protocol employed relied on both conformational search and molecular dynamics methodologies to account for the flexibility of both the ligand and the protein receptor. The conformational search of the LT:inhibitor complex showed that, compared to 2, the new compound can insert one more hydroxy group within the protein binding site. Molecular dynamics simulations showed that, in turn, this may trigger a series of rearrangements and reorientations of side chains and crystallographic water molecules in the toxin, leading to new H-bond contacts which may result in enhanced affinity of the new inhibitor. FEP calculations were performed by mutating the structure of 2 in solution and in the protein complex, and the prediction was made that the second-generation mimic should be a stronger binder than its parent compound.

  11. Molecular profiling of ADAM12 and ADAM17 genes in human malignant melanoma.

    PubMed

    Cireap, Natalia; Narita, Diana

    2013-10-01

    ADAM12 and ADAM17 proteins belong to a family of transmembrane disintegrin-containing metalloproteinases (ADAMs) involved in the proteins ectodomain shedding and cell-cell and cell-matrix interactions. However, the specific biological functions of ADAMs are still unclear and, until now, these proteins were not investigated yet in melanoma. The aim of this study was to analyze the splicing variants of ADAM12 (L and S) and ADAM17 gene expression in melanoma at transcriptional and translational level in comparison with control (non-tumor) tissues. Taking in account that ADAM17 sheddase is involved in the modulation of TNF-α (tumor necrosis factor alpha), we analyzed also this cytokine in the plasma of the same patients before any treatment, and we compared the results with healthy controls. Quantitative-RT-PCR and immunohistochemistry were used to analyze ADAM12 and ADAM17 genes expression and the analysis of TNF-α expression was carried out in the plasma using ELISA. We demonstrated that ADAM12L splicing variant together with ADAM17 gene are strongly overexpressed in melanomas, whereas ADAM12S, although up-regulated when compared with the non-tumor controls, the difference was not statistically significant. When we compared the levels of expression for the ADAMs genes according to the tumor stage, we observed that all three investigated genes were significantly overexpressed in advanced stage in comparison with early stage melanomas. In the plasma of the same patients, the expression of TNF-α was up-regulated and significantly correlated with the expression of ADAM17 and respectively, with the advanced tumor stage.

  12. Crystal structure and functional insights into uracil-DNA glycosylase inhibition by phage ϕ29 DNA mimic protein p56

    PubMed Central

    Baños-Sanz, José Ignacio; Mojardín, Laura; Sanz-Aparicio, Julia; Lázaro, José M.; Villar, Laurentino; Serrano-Heras, Gemma; González, Beatriz; Salas, Margarita

    2013-01-01

    Uracil-DNA glycosylase (UDG) is a key repair enzyme responsible for removing uracil residues from DNA. Interestingly, UDG is the only enzyme known to be inhibited by two different DNA mimic proteins: p56 encoded by the Bacillus subtilis phage ϕ29 and the well-characterized protein Ugi encoded by the B. subtilis phage PBS1/PBS2. Atomic-resolution crystal structures of the B. subtilis UDG both free and in complex with p56, combined with site-directed mutagenesis analysis, allowed us to identify the key amino acid residues required for enzyme activity, DNA binding and complex formation. An important requirement for complex formation is the recognition carried out by p56 of the protruding Phe191 residue from B. subtilis UDG, whose side-chain is inserted into the DNA minor groove to replace the flipped-out uracil. A comparative analysis of both p56 and Ugi inhibitors enabled us to identify their common and distinctive features. Thereby, our results provide an insight into how two DNA mimic proteins with different structural and biochemical properties are able to specifically block the DNA-binding domain of the same enzyme. PMID:23671337

  13. Crystal structure and functional insights into uracil-DNA glycosylase inhibition by phage Φ29 DNA mimic protein p56.

    PubMed

    Baños-Sanz, José Ignacio; Mojardín, Laura; Sanz-Aparicio, Julia; Lázaro, José M; Villar, Laurentino; Serrano-Heras, Gemma; González, Beatriz; Salas, Margarita

    2013-07-01

    Uracil-DNA glycosylase (UDG) is a key repair enzyme responsible for removing uracil residues from DNA. Interestingly, UDG is the only enzyme known to be inhibited by two different DNA mimic proteins: p56 encoded by the Bacillus subtilis phage 29 and the well-characterized protein Ugi encoded by the B. subtilis phage PBS1/PBS2. Atomic-resolution crystal structures of the B. subtilis UDG both free and in complex with p56, combined with site-directed mutagenesis analysis, allowed us to identify the key amino acid residues required for enzyme activity, DNA binding and complex formation. An important requirement for complex formation is the recognition carried out by p56 of the protruding Phe191 residue from B. subtilis UDG, whose side-chain is inserted into the DNA minor groove to replace the flipped-out uracil. A comparative analysis of both p56 and Ugi inhibitors enabled us to identify their common and distinctive features. Thereby, our results provide an insight into how two DNA mimic proteins with different structural and biochemical properties are able to specifically block the DNA-binding domain of the same enzyme.

  14. A minimalist chemical model of matrix metalloproteinases--can small peptides mimic the more rigid metal binding sites of proteins?

    PubMed

    Árus, Dávid; Nagy, Nóra Veronika; Dancs, Ágnes; Jancsó, Attila; Berkecz, Róbert; Gajda, Tamás

    2013-09-01

    In order to mimic the active center of matrix metalloproteinases (MMPs), we synthesized a pentadecapeptide (Ac-KAHEFGHSLGLDHSK-NH2) corresponding to the catalytic zinc(II) binding site of human MMP-13. The multi-domain structural organization of MMPs fundamentally determines their metal binding affinity, catalytic activity and selectivity. Our potentiometric, UV-visible, CD, EPR, NMR, mass spectrometric and kinetic studies are aimed to explore the usefulness of such flexible peptides to mimic the more rigid metal binding sites of proteins, to examine the intrinsic metal binding properties of this naked sequence, as well as to contribute to the development of a minimalist, peptide-based chemical model of MMPs, including the catalytic properties. Since the multiimidazole environment is also characteristic for copper(II), and recently copper(II) containing variants of MMPs have been identified, we also studied the copper(II) complexes of the above peptide. Around pH 6-7 the peptide, similarly to MMPs, offers a {3Nim} coordination binding site for both zinc(II) and copper(II). In the case of copper(II), the formation of amide coordinated species at higher pH abolished the analogy with the copper(II) containing MMP variant. On the other hand, the zinc(II)-peptide system mimics some basic features of the MMP active sites: the main species around pH7 (ZnH2L) possesses a {3Nim,H2O} coordination environment, the deprotonation of the zinc-bound water takes place near the physiological pH, it forms relatively stable ternary complexes with hydroxamic acids, and the species ZnH2L(OH) and ZnH2L(OH)2 have notable hydrolytic activity between pH7 and 9.

  15. Myositis Mimics.

    PubMed

    Michelle, E Harlan; Mammen, Andrew L

    2015-10-01

    Patients with autoimmune myositis typically present with muscle weakness, elevated serum levels of muscle enzymes, and abnormal muscle biopsies. However, patients with other acquired myopathies or genetic muscle diseases may have remarkably similar presentations. Making the correct diagnosis of another muscle disease can prevent these patients from being exposed to the risks of immunosuppressive medications, which benefit those with myositis, but not those with other types of muscle disease. Here, we review some of the most common acquired and inherited muscle diseases that can mimic autoimmune myositis, including inclusion body myositis, limb girdle muscular dystrophies, metabolic myopathies, mitochondrial myopathies, and endocrine myopathies. We emphasize aspects of the medical history, physical exam, laboratory evaluation, and muscle biopsy analysis that can help clinicians distinguish myositis mimics from true autoimmune myositis.

  16. Exosome release of ADAM15 and the functional implications of human macrophage-derived ADAM15 exosomes.

    PubMed

    Lee, Hee Doo; Koo, Bon-Hun; Kim, Yeon Hyang; Jeon, Ok-Hee; Kim, Doo-Sik

    2012-07-01

    A disintegrin and metalloproteinase 15 (ADAM15), the only ADAM protein containing an Arg-Gly-Asp (RGD) motif in its disintegrin-like domain, is a widely expressed membrane protein that is involved in tumor progression and suppression. However, the underlying mechanism of ADAM15-mediated tumor suppression is not clearly understood. This study demonstrates that ADAM15 is released as an exosomal component, and ADAM15 exosomes exert tumor suppressive activities. We found that exosomal ADAM15 release is stimulated by phorbol 12-myristate 13-acetate, a typical protein kinase C activator, in various tumor cell types, and this results in a corresponding decrease in plasma membrane-associated ADAM15. Exosomes rich in ADAM15 display enhanced binding affinity for integrin αvβ3 in an RGD-dependent manner and suppress vitronectin- and fibronectin-induced cell adhesion, growth, and migration, as well as in vivo tumor growth. Exosomal ADAM15 is released from human macrophages, and macrophage-derived ADAM15 exosomes have tumor inhibitory effects. This work suggests a primary role of ADAM15 for exosome-mediated tumor suppression, as well as functional significance of exosomal ADAM protein in antitumor immunity.

  17. Approved drug mimics of short peptide ligands from protein interaction motifs.

    PubMed

    Parthasarathi, Laavanya; Casey, Fergal; Stein, Amelie; Aloy, Patrick; Shields, Denis C

    2008-10-01

    Most biological functions are regulated through complex networks of transient protein interactions, and, thus, finding effective ways to modulate them would represent an important step towards defining the next generation of drugs. In this study, we set out to determine if existing approved drugs may represent a good source of compounds from which initial lead inhibitors of protein-protein interactions mediated by short peptide regions may be drawn. Peptide structures were defined in terms of pharmacophores and searched against U.S. Food and Drug Administration (FDA)-approved drugs to identify similar compounds. The top ranking matches (using a score that corrects root-mean-square deviation (rmsd) for the number of matched pharmacophores and for the number of drug rotatable bonds) included a number of nuclear receptor ligands that matched allosterically to the corepressor binding site of peroxisome proliferator-activated receptor alpha (PPARalpha). The top ranking drug matches were docked to the peptide-binding site using AUTODOCK. The majority of the top-ranking matches showed a negative estimated free energy change upon binding that is comparable to, or greater than, that of the original peptide. We conclude that the usage of certain approved drugs may represent a useful strategy in inhibiting specific protein-protein interactions. Such a strategy may benefit from the increased likelihood that developed compounds might have favorable bioactivity and safety profiles in clinical use.

  18. A library of MiMICs allows tagging of genes and reversible, spatial and temporal knockdown of proteins in Drosophila

    PubMed Central

    Nagarkar-Jaiswal, Sonal; Lee, Pei-Tseng; Campbell, Megan E; Chen, Kuchuan; Anguiano-Zarate, Stephanie; Cantu Gutierrez, Manuel; Busby, Theodore; Lin, Wen-Wen; He, Yuchun; Schulze, Karen L; Booth, Benjamin W; Evans-Holm, Martha; Venken, Koen JT; Levis, Robert W; Spradling, Allan C; Hoskins, Roger A; Bellen, Hugo J

    2015-01-01

    Here, we document a collection of ∼7434 MiMIC (Minos Mediated Integration Cassette) insertions of which 2854 are inserted in coding introns. They allowed us to create a library of 400 GFP-tagged genes. We show that 72% of internally tagged proteins are functional, and that more than 90% can be imaged in unfixed tissues. Moreover, the tagged mRNAs can be knocked down by RNAi against GFP (iGFPi), and the tagged proteins can be efficiently knocked down by deGradFP technology. The phenotypes associated with RNA and protein knockdown typically correspond to severe loss of function or null mutant phenotypes. Finally, we demonstrate reversible, spatial, and temporal knockdown of tagged proteins in larvae and adult flies. This new strategy and collection of strains allows unprecedented in vivo manipulations in flies for many genes. These strategies will likely extend to vertebrates. DOI: http://dx.doi.org/10.7554/eLife.05338.001 PMID:25824290

  19. Investigation of the catalytic mechanism of a synthetic DNAzyme with protein-like functionality: an RNaseA mimic?

    PubMed

    Thomas, Jason M; Yoon, Jung-Ki; Perrin, David M

    2009-04-22

    The protein enzyme ribonuclease A (RNaseA) cleaves RNA with catalytic perfection, although with little sequence specificity, by a divalent metal ion (M(2+))-independent mechanism in which a pair of imidazoles provides general acid and base catalysis, while a cationic amine provides electrostatic stabilization of the transition state. Synthetic imitation of this remarkable organo-catalyst ("RNaseA mimicry") has been a longstanding goal in biomimetic chemistry. The 9(25)-11 DNAzyme contains synthetically modified nucleotides presenting both imidazole and cationic amine side chains, and catalyzes RNA cleavage with turnover in the absence of M(2+) similarly to RNaseA. Nevertheless, the catalytic roles, if any, of the "protein-like" functional groups have not been defined, and hence the question remains whether 9(25)-11 engages any of these functionalities to mimic aspects of the mechanism of RNaseA. To address this question, we report a mechanistic investigation of 9(25)-11 catalysis wherein we have employed a variety of experiments, such as DNAzyme functional group deletion, mechanism-based affinity labeling, and bridging and nonbridging phosphorothioate substitution of the scissile phosphate. Several striking parallels exist between the results presented here for 9(25)-11 and the results of analogous experiments applied previously to RNaseA. Specifically, our results implicate two particular imidazoles in general acid and base catalysis and suggest that a specific cationic amine stabilizes the transition state via diastereoselective interaction with the scissile phosphate. Overall, 9(25)-11 appears to meet the minimal criteria of an RNaseA mimic; this demonstrates how added synthetic functionality can expand the mechanistic repertoire available to a synthetic DNA-based catalyst.

  20. Latent membrane protein 1 of Epstein-Barr virus mimics a constitutively active receptor molecule.

    PubMed Central

    Gires, O; Zimber-Strobl, U; Gonnella, R; Ueffing, M; Marschall, G; Zeidler, R; Pich, D; Hammerschmidt, W

    1997-01-01

    Latent membrane protein 1 (LMP1) of Epstein-Barr virus (EBV) is an integral membrane protein which has transforming potential and is necessary but not sufficient for B-cell immortalization by EBV. LMP1 molecules aggregate in the plasma membrane and recruit tumour necrosis factor receptor (TNF-R) -associated factors (TRAFs) which are presumably involved in the signalling cascade leading to NF-kappaB activation by LMP1. Comparable activities are mediated by CD40 and other members of the TNF-R family, which implies that LMP1 could function as a receptor. LMP1 lacks extended extracellular domains similar to beta-adrenergic receptors but, in contrast, it also lacks any motifs involved in ligand binding. By using LMP1 mutants which can be oligomerized at will, we show that the function of LMP1 in 293 cells and B cells is solely dependent on oligomerization of its carboxy-terminus. Biochemically, oligomerization is an intrinsic property of the transmembrane domain of wild-type LMP1 and causes a constitutive phenotype which can be conferred to the signalling domains of CD40 or the TNF-2 receptor. In EBV, immortalized B cells cross-linking in conjunction with membrane targeting of the carboxy-terminal signalling domain of LMP1 is sufficient for its biological activities. Thus, LMP1 acts like a constitutively activated receptor whose biological activities are ligand-independent. PMID:9359753

  1. Evolution of strategies to prepare synthetic mimics of carboxylate-bridged diiron protein active sites.

    PubMed

    Do, Loi H; Lippard, Stephen J

    2011-12-01

    We present a comprehensive review of research conducted in our laboratory in pursuit of the long-term goal of reproducing the structures and reactivity of carboxylate-bridged diiron centers used in biology to activate dioxygen for the conversion of hydrocarbons to alcohols and related products. This article describes the evolution of strategies devised to achieve these goals and illustrates the challenges in getting there. Particular emphasis is placed on controlling the geometry and coordination environment of the diiron core, preventing formation of polynuclear iron clusters, maintaining the structural integrity of model complexes during reactions with dioxygen, and tuning the ligand framework to stabilize desired oxygenated diiron species. Studies of the various model systems have improved our understanding of the electronic and physical characteristics of carboxylate-bridged diiron units and their reactivity toward molecular oxygen and organic moieties. The principles and lessons that have emerged from these investigations will guide future efforts to develop more sophisticated diiron protein model complexes.

  2. Stimulation of non-amyloidogenic processing of amyloid-β protein precursor by cryptotanshinone involves activation and translocation of ADAM10 and PKC-α.

    PubMed

    Durairajan, Siva Sundara Kumar; Liu, Liang-Feng; Lu, Jia-Hong; Koo, Irene; Maruyama, Kei; Chung, Sookja K; Huang, Jian-Dong; Li, Min

    2011-01-01

    Cerebral deposition of amyloid-β peptide (Aβ) plaques is now considered the central feature of Alzheimer's disease. Recent studies suggest that cryptotanshinone (CTS) extracted from the root of Salvia miltiorrhiza Bunge could be used for the prevention and treatment of Alzheimer's disease. In this study, we investigated the role of CTS on non-amyloidogenic processing of amyloid-β protein precursor (AβPP) as well as its regulation by protein kinase C (PKC). Treatment with CTS dose-dependently and significantly reduced both intracellular and secreted levels of Aβ40 and Aβ42 in N2a mouse neuroblastoma cells stably expressing human SwedishAβPP (N2a-SwedAβPP). Using N2a-SwedAβPP and human neuroblastoma SHSY5Y cells, it was demonstrated that CTS significantly and dose-dependently increased the production of sAβPPα and C-terminal fragment-α (CTF-α) from AβPP. At the same time, CTS specifically increased the maturation of "a disintegrin and metalloproteinase-10" (ADAM10), an α-secretase candidate. The increase of sAβPPα secretion by CTS was blocked by the hydroxamate-based inhibitors GI254023X and GW280264X, and by the PKC-α inhibitor GÖ6976, suggesting involvement of the ADAM10 and PKC-α in CTS-induced α-secretase cleavage. In other experiments, CTS induced the phosphorylation of PKC-α indicating that PKC-α is involved in CTS-induced sAβPPα secretion. Furthermore, treatment of neuroblastoma cells with CTS induced the co-translocation of ADAM10 and PKC-α to the cell membrane, the site at which AβPP was cleaved, and this translocation was significantly reduced by GÖ6976. These results suggest that CTS-induced sAβPPα secretion is regulated by a PKC-α and ADAM10 cascade in neuroblastoma cells and may be involved in the lowering of Aβ production.

  3. Highly efficient enzyme encapsulation in a protein nanocage: towards enzyme catalysis in a cellular nanocompartment mimic

    NASA Astrophysics Data System (ADS)

    Schoonen, Lise; Nolte, Roeland J. M.; van Hest, Jan C. M.

    2016-07-01

    The study of enzyme behavior in small nanocompartments is crucial for the understanding of biocatalytic processes in the cellular environment. We have developed an enzymatic conjugation strategy to attach a model enzyme to the interior of a cowpea chlorotic mottle virus capsid. It is shown that with this methodology high encapsulation efficiencies can be achieved. Additionally, we demonstrate that the encapsulation does not affect the enzyme performance in terms of a decreased activity or a hampered substrate diffusion. Finally, it is shown that the encapsulated enzymes are protected against proteases. We believe that our strategy can be used to study enzyme kinetics in an environment that approaches physiological conditions.The study of enzyme behavior in small nanocompartments is crucial for the understanding of biocatalytic processes in the cellular environment. We have developed an enzymatic conjugation strategy to attach a model enzyme to the interior of a cowpea chlorotic mottle virus capsid. It is shown that with this methodology high encapsulation efficiencies can be achieved. Additionally, we demonstrate that the encapsulation does not affect the enzyme performance in terms of a decreased activity or a hampered substrate diffusion. Finally, it is shown that the encapsulated enzymes are protected against proteases. We believe that our strategy can be used to study enzyme kinetics in an environment that approaches physiological conditions. Electronic supplementary information (ESI) available: Experimental procedures for the cloning, expression, and purification of all proteins, as well as supplementary figures and calculations. See DOI: 10.1039/c6nr04181g

  4. Mimics of Host Defense Proteins; Strategies for Translation to Therapeutic Applications.

    PubMed

    Scott, Richard W; Tew, Gregory N

    2017-01-01

    New infection treatments are urgently needed to combat the rising threat of multi-drug resistant bacteria. Despite early clinical set-backs attention has re-focused on host defense proteins (HDPs), as potential sources for new and effective antimicrobial treatments. HDPs appear to act at multiple targets and their repertoire includes disruptive membrane and intracellular activities against numerous types of pathogens as well as immune modulatory functions in the host. Importantly, these novel activities are associated with a low potential for emergence of resistance and little crossresistance with other antimicrobial agents. Based on these properties, HDPs appear to be ideal candidates for new antibiotics; however, their development has been plagued by the many therapeutic limitations associated with natural peptidic agents. This review focuses on HDP mimetic approaches aimed to improve metabolic stability, pharmacokinetics, safety and manufacturing processes. Early efforts with β-peptide or peptoid analogs focused on recreating stable facially amphiphilic structures but demonstrated that antimicrobial activity was modulated by more, complex structural properties. Several approaches have used lipidation to increase the hydrophobicity and membrane activity. One lead compound, LTX-109, has entered clinical study as a topical agent to treat impetigo and nasal decolonization. In a more significant departure from the amino acid like peptidomimetics, considerable effort has been directed at developing amphiphilic compounds that recapitulate the structural and biological properties of HDPs on small abiotic scaffolds. The lead compound from this approach, brilacidin, has completed two phase 2 studies as an intravenous agent for skin infections.

  5. Molecular and Structural Characterization of a Novel Escherichia coli Interleukin Receptor Mimic Protein

    PubMed Central

    Moriel, Danilo G.; Paxman, Jason J.; Lo, Alvin W.; Tan, Lendl; Sullivan, Matthew J.; Dando, Samantha J.; Beatson, Scott A.

    2016-01-01

    ABSTRACT Urinary tract infection (UTI) is a disease of extremely high incidence in both community and nosocomial settings. UTIs cause significant morbidity and mortality, with approximately 150 million cases globally per year. Uropathogenic Escherichia coli (UPEC) is the primary cause of UTI and is generally treated empirically. However, the rapidly increasing incidence of UTIs caused by multidrug-resistant UPEC strains has led to limited available treatment options and highlights the urgent need to develop alternative treatment and prevention strategies. In this study, we performed a comprehensive analysis to define the regulation, structure, function, and immunogenicity of recently identified UPEC vaccine candidate C1275 (here referred to as IrmA). We showed that the irmA gene is highly prevalent in UPEC, is cotranscribed with the biofilm-associated antigen 43 gene, and is regulated by the global oxidative stress response OxyR protein. Localization studies identified IrmA in the UPEC culture supernatant. We determined the structure of IrmA and showed that it adopts a unique domain-swapped dimer architecture. The dimeric structure of IrmA displays similarity to those of human cytokine receptors, including the interleukin-2 receptor (IL-2R), interleukin-4 receptor (IL-4R), and interleukin-10 receptor (IL-10R) binding domains, and we showed that purified IrmA can bind to their cognate cytokines. Finally, we showed that plasma from convalescent urosepsis patients contains high IrmA antibody titers, demonstrating the strong immunogenicity of IrmA. Taken together, our results indicate that IrmA may play an important role during UPEC infection. PMID:26980835

  6. A Critical Reappraisal of Neutrophil Extracellular Traps and NETosis Mimics Based on Differential Requirements for Protein Citrullination

    PubMed Central

    Konig, Maximilian F.; Andrade, Felipe

    2016-01-01

    NETosis, an antimicrobial form of neutrophil cell death, is considered a primary source of citrullinated autoantigens in rheumatoid arthritis (RA) and immunogenic DNA in systemic lupus erythematosus (SLE). Activation of the citrullinating enzyme peptidylarginine deiminase type 4 (PAD4) is believed to be essential for neutrophil extracellular trap (NET) formation and NETosis. PAD4 is therefore viewed as a promising therapeutic target to inhibit the formation of NETs in both diseases. In this review, we examine the evidence for PAD4 activation during NETosis and provide experimental data to suggest that protein citrullination is not a universal feature of NETs. We delineate two distinct biological processes, leukotoxic hypercitrullination (LTH) and defective mitophagy, which have been erroneously classified as “NETosis.” While these NETosis mimics share morphological similarities with NETosis (i.e., extracellular DNA release), they are biologically distinct. As such, these processes can be readily classified by their stimuli, activation of distinct biochemical pathways, the presence of hypercitrullination, and antimicrobial effector function. NETosis is an antimicrobial form of cell death that is NADPH oxidase-dependent and not associated with hypercitrullination. In contrast, LTH is NADPH oxidase-independent and not bactericidal. Rather, LTH represents a bacterial strategy to achieve immune evasion. It is triggered by pore-forming pathways and equivalent signals that cumulate in calcium-dependent hyperactivation of PADs, protein hypercitrullination, and neutrophil death. The generation of citrullinated autoantigens in RA is likely driven by LTH, but not NETosis. Mitochondrial DNA (mtDNA) expulsion, the result of a constitutive defect in mitophagy, represents a second NETosis mimic. In the presence of interferon-α and immune complexes, this process can generate highly interferogenic oxidized mtDNA, which has previously been mistaken for NETosis in SLE

  7. John Adams' essential tremor.

    PubMed

    Louis, Elan D; Kavanagh, Patricia

    2005-12-01

    John Adams (1735-1826), one of the signers of the Declaration of Independence, was the second President of the United States. Adams had tremor for many years, about which little has been written. We examined John Adams' penmanship over a 62-year period and studied his correspondence and diaries. It is not clear when Adams' tremor began, although in a diary entry dated 6 December 1760, when Adams was 25 years old, there is evidence of low-amplitude kinetic tremor. The tremor continued in his written correspondence, becoming more persistent over time. Later in life, the clarity of his written correspondence diminished, with greater decomposition of characters and a reduction in the size of individual characters. This finding raises some speculation as to whether Adams could have been developing some parkinsonism, although the evidence in favor of this is not compelling. The most likely diagnosis was essential tremor.

  8. A Disintegrin and Metalloproteinase10 (ADAM10) Regulates NOTCH Signaling during Early Retinal Development.

    PubMed

    Toonen, Joseph A; Ronchetti, Adam; Sidjanin, D J

    2016-01-01

    ADAM10 and ADAM17 are two closely related members of the ADAM (a disintegrin and metalloprotease) family of membrane-bound sheddases, which proteolytically cleave surface membrane proteins. Both ADAM10 and ADAM17 have been implicated in the proteolytic cleavage of NOTCH receptors and as such regulators of NOTCH signaling. During retinal development, NOTCH signaling facilitates retinal neurogenesis by maintaining progenitor cells in a proliferative state and by mediating retinal cell fates. However, the roles of ADAM10 and ADAM17 in the retina are not well defined. In this study, we set out to clarify the roles of ADAM10 and ADAM17 during early retinal development. The retinal phenotype of conditionally abated Adam17 retinae (Adam17 CKO) did not differ from the controls whereas conditionally ablated Adam10 retinae (Adam10 CKO) exhibited abnormal morphogenesis characterized by the formation of rosettes and a loss of retinal laminae phenotypically similar to morphological abnormalities identified in mice with retinal NOTCH signaling deficiency. Additionally, Adam10 CKO retinae exhibited abnormal neurogenesis characterized by fewer proliferating progenitor cells and greater differentiation of early photoreceptors and retinal ganglion cells. Moreover, constitutive activation of the NOTCH1-intracellular domain (N1-ICD) rescued Adam10 CKO abnormal neurogenesis, as well as abnormal retinal morphology by maintaining retinal cells in the progenitor state. Collectively these findings provide in vivo genetic evidence that ADAM10, and not ADAM17, is indispensable for proper retinal development as a regulator of NOTCH signaling.

  9. A Disintegrin and Metalloproteinase10 (ADAM10) Regulates NOTCH Signaling during Early Retinal Development

    PubMed Central

    Toonen, Joseph A.; Ronchetti, Adam; Sidjanin, D. J.

    2016-01-01

    ADAM10 and ADAM17 are two closely related members of the ADAM (a disintegrin and metalloprotease) family of membrane-bound sheddases, which proteolytically cleave surface membrane proteins. Both ADAM10 and ADAM17 have been implicated in the proteolytic cleavage of NOTCH receptors and as such regulators of NOTCH signaling. During retinal development, NOTCH signaling facilitates retinal neurogenesis by maintaining progenitor cells in a proliferative state and by mediating retinal cell fates. However, the roles of ADAM10 and ADAM17 in the retina are not well defined. In this study, we set out to clarify the roles of ADAM10 and ADAM17 during early retinal development. The retinal phenotype of conditionally abated Adam17 retinae (Adam17 CKO) did not differ from the controls whereas conditionally ablated Adam10 retinae (Adam10 CKO) exhibited abnormal morphogenesis characterized by the formation of rosettes and a loss of retinal laminae phenotypically similar to morphological abnormalities identified in mice with retinal NOTCH signaling deficiency. Additionally, Adam10 CKO retinae exhibited abnormal neurogenesis characterized by fewer proliferating progenitor cells and greater differentiation of early photoreceptors and retinal ganglion cells. Moreover, constitutive activation of the NOTCH1-intracellular domain (N1-ICD) rescued Adam10 CKO abnormal neurogenesis, as well as abnormal retinal morphology by maintaining retinal cells in the progenitor state. Collectively these findings provide in vivo genetic evidence that ADAM10, and not ADAM17, is indispensable for proper retinal development as a regulator of NOTCH signaling. PMID:27224017

  10. The ADAMS interactive interpreter

    SciTech Connect

    Rietscha, E.R.

    1990-12-17

    The ADAMS (Advanced DAta Management System) project is exploring next generation database technology. Database management does not follow the usual programming paradigm. Instead, the database dictionary provides an additional name space environment that should be interactively created and tested before writing application code. This document describes the implementation and operation of the ADAMS Interpreter, an interactive interface to the ADAMS data dictionary and runtime system. The Interpreter executes individual statements of the ADAMS Interface Language, providing a fast, interactive mechanism to define and access persistent databases. 5 refs.

  11. Targeting ADAM12 in human disease: head, body or tail?

    PubMed

    Jacobsen, J; Wewer, U M

    2009-01-01

    ADAM12/meltrin alpha is a type I transmembrane multidomain protein involved in tumor progression and other severe diseases, including osteoarthritis, and as such could be considered as a potential drug target. In addition to protease activity, ADAM12 possesses cell binding and cell signaling properties. This functional trinity is reflected in the structure of ADAM12, which can be divided into head, body, and tail. The head of the protein (consisting of the pro and catalytic domains) mediates processing of growth factors and cytokines and has been implicated in epidermal growth factor (EGF) and insulin-like growth factor receptor signaling. The body of the protein (consisting of the disintegrin, cysteine-rich, and EGF-like domains) is involved in contacts with the extracellular matrix and other cells through interactions with integrins and syndecans. Finally, the tail of the protein (consisting of the cytoplasmic domain) is engaged in interactions with intracellular signaling molecules. In many studies, ADAM12 overexpression has been correlated with disease, and ADAM12 has been shown to promote tumor growth and progression in cancer. On the other hand, protective effects of ADAM12 in disease have also been reported. Future investigations should address the precise mechanisms of ADAM12 in disease and biology in order to counterbalance the benefits from targeting ADAM12 therapeutically with possible side effects. This review describes the biology of ADAM12, its association with disease, and evaluates the possible approaches to targeting ADAM12 in human disease.

  12. ADAM15 expression is downregulated in melanoma metastasis compared to primary melanoma

    SciTech Connect

    Ungerer, Christopher; Doberstein, Kai; Boehm, Beate; Pfeilschifter, Josef; Mihic-Probst, Daniela; Gutwein, Paul

    2010-10-22

    Research highlights: {yields} Strong ADAM15 expression is found in normal melanocytes. {yields} ADAM15 expression is significantly downregulated in patients with melanoma metastasis. {yields} TGF-{beta} can downregulate ADAM15 expression in melanoma cells. {yields} Overexpression of ADAM15 in melanoma cells inhibits migration, proliferation and invasion of melanoma cells. {yields} Conclusion: ADAM15 represents an tumor suppressor protein in melanoma. -- Abstract: In a mouse melanoma metastasis model it has been recently shown that ADAM15 overexpression in melanoma cells significantly reduced the number of metastatic nodules on the lung. Unfortunately, the expression of ADAM15 in human melanoma tissue has not been determined so far. In our study, we characterized the expression of ADAM15 in tissue micro-arrays of patients with primary melanoma with melanoma metastasis. ADAM15 was expressed in melanocytes and endothelial cells of benign nevi and melanoma tissue. Importantly, ADAM15 was significantly downregulated in melanoma metastasis compared to primary melanoma. We further demonstrate that IFN-{gamma} and TGF-{beta} downregulate ADAM15 protein levels in melanoma cells. To investigate the role of ADAM15 in melanoma progression, we overexpressed ADAM15 in melanoma cells. Importantly, overexpression of ADAM15 in melanoma cells reduced the migration, invasion and the anchorage dependent and independent cell growth of melanoma cells. In summary, the downregulation of ADAM15 plays an important role in melanoma progression and ADAM15 act as a tumorsuppressor in melanoma.

  13. Alternative mRNA splicing generates two distinct ADAM12 prodomain variants.

    PubMed

    Duhachek-Muggy, Sara; Li, Hui; Qi, Yue; Zolkiewska, Anna

    2013-01-01

    Human ADAM12, transcript variant 1 (later on referred to as Var-1b), present in publicly available databases contains the sequence 5'-GTAATTCTG-3' at the nucleotide positions 340-348 of the coding region, at the 3' end of exon 4. The translation product of this variant, ADAM12-Lb, includes the three amino acid motif (114)VIL(116) in the prodomain. This motif is not conserved in ADAM12 from different species and is not present in other human ADAMs. Currently, it is not clear whether a shorter variant, Var-1a, encoding the protein version without the (114)VIL(116) motif, ADAM12-La, is expressed in human. In this work, we have established that human mammary epithelial cells and breast cancer cells express both Var-1a and Var-1b transcripts. Importantly, the proteolytic processing and intracellular trafficking of the corresponding ADAM12-La and ADAM12-Lb proteins are different. While ADAM12-La is cleaved and trafficked to the cell surface in a manner similar to ADAM12 in other species, ADAM12-Lb is retained in the ER and is not proteolytically processed. Furthermore, the relative abundance of ADAM12-La and ADAM12-Lb proteins detected in several breast cancer cell lines varies significantly. We conclude that the canonical form of transmembrane ADAM12 is represented by Var-1a/ADAM12-La, rather than Var-1b/ADAM12-Lb currently featured in major sequence databases.

  14. ADAM12 is expressed by astrocytes during experimental demyelination.

    PubMed

    Baertling, Fabian; Kokozidou, Maria; Pufe, Thomas; Clarner, Tim; Windoffer, Reinhard; Wruck, Christoph J; Brandenburg, Lars-Ove; Beyer, Cordian; Kipp, Markus

    2010-04-22

    A disintegrin and metalloproteinase (ADAM) 12 represents a member of a large family of similarly structured multi-domain proteins. In the central nervous system (CNS), ADAM12 has been suggested to play a role in brain development, glioblastoma cell proliferation, and in experimental autoimmune encephalomyelitis. Furthermore, ADAM12 was reported to be almost exclusively expressed by oligodendrocytes and could, therefore, be considered as suitable marker for this cell type. In the present study, we investigated ADAM12 expression in the healthy and pathologically altered murine CNS. As pathological paradigm, we used the cuprizone demyelination model in which myelin loss during multiple sclerosis is imitated. Besides APC(+) oligodendrocytes, SMI311(+) neurons and GFAP(+) astrocytes express ADAM12 in the adult mouse brain. ADAM12 expression was further analyzed in vitro. After the induction of demyelination, we observed that activated astrocytes are the main source of ADAM12 in brain regions affected by oligodendrocyte loss. Exposure of astrocytes in vitro to either lipopolysaccharides (LPS), tumor necrosis factor alpha (TNFalpha), glutamate, or hydrogen peroxide revealed a highly stimulus-specific regulation of ADAM12 expression which was not seen in microglial BV2 cells. It appears that LPS- and TNFalpha-induced ADAM12 expression is mediated via the classic NFkappaB pathway. In summary, we demonstrated that ADAM12 is not a suitable marker for oligodendrocytes. Our results further suggest that ADAM12 might be implicated in the course of distinct CNS diseases such as demyelinating disorders.

  15. A doppel alpha-helix peptide fragment mimics the copper(II) interactions with the whole protein.

    PubMed

    La Mendola, Diego; Magrì, Antonio; Campagna, Tiziana; Campitiello, Maria Anna; Raiola, Luca; Isernia, Carla; Hansson, Orjan; Bonomo, Raffaele P; Rizzarelli, Enrico

    2010-06-01

    The doppel protein (Dpl) is the first homologue of the prion protein (PrP(C)) to be discovered; it is overexpressed in transgenic mice that lack the prion gene, resulting in neurotoxicity. The whole prion protein is able to inhibit Dpl neurotoxicity, and its N-terminal domain is the determinant part of the protein function. This region represents the main copper(II) binding site of PrP(C). Dpl is able to bind at least one copper ion, and the specific metal-binding site has been identified as the histidine residue at the beginning of the third helical region. However, a reliable characterization of copper(II) coordination features has not been reported. In a previous paper, we studied the copper(II) interaction with a peptide that encompasses only the loop region potentially involved in metal binding. Nevertheless, we did not find a complete match between the EPR spectroscopic parameters of the copper(II) complexes formed with the synthesized peptide and those reported for the copper(II) binding sites of the whole protein. Herein, the synthesis of the human Dpl peptide fragment hDpl(122-139) (Ac-KPDNKLHQQVLWRLVQEL-NH(2)) and its copper(II) complex species are reported. This peptide encompasses the third alpha helix and part of the loop linking the second and the third helix of human doppel protein. The single-point-mutated peptide, hDpl(122-139)D124N, in which aspartate 124 replaces an asparagine residue, was also synthesized. This peptide was used to highlight the role of the carboxylate group on both the conformation preference of the Dpl fragment and its copper(II) coordination features. NMR spectroscopic measurements show that the hDpl(122-139) peptide fragment is in the prevailing alpha-helix conformation. It is localized within the 127-137 amino acid residue region that represents a reliable conformational mimic of the related protein domain. A comparison with the single-point-mutated hDpl(122-139)D124N reveals the significant role played by the aspartic

  16. Characterization of Mammalian ADAM2 and Its Absence from Human Sperm

    PubMed Central

    Choi, Heejin; Jin, Sora; Kwon, Jun Tae; Kim, Jihye; Jeong, Juri; Kim, Jaehwan; Jeon, Suyeon; Park, Zee Yong; Jung, Kang-Jin; Park, Kwangsung; Cho, Chunghee

    2016-01-01

    The members of the ADAM (a disintegrin and metalloprotease) family are membrane-anchored multi-domain proteins that play prominent roles in male reproduction. ADAM2, which was one of the first identified ADAMs, is the best studied ADAM in reproduction. In the male germ cells of mice, ADAM2 and other ADAMs form complexes that contribute to sperm-sperm adhesion, sperm-egg interactions, and the migration of sperm in the female reproductive tract. Here, we generated specific antibodies against mouse and human ADAM2, and investigated various features of ADAM2 in mice, monkeys and humans. We found that the cytoplasmic domain of ADAM2 might enable the differential association of this protein with other ADAMs in mice. Western blot analysis with the anti-human ADAM2 antibodies showed that ADAM2 is present in the testis and sperm of monkeys. Monkey ADAM2 was found to associate with chaperone proteins in testis. In humans, we identified ADAM2 as a 100-kDa protein in the testis, but failed to detect it in sperm. This is surprising given the results in mice and monkeys, but it is consistent with the failure of ADAM2 identification in the previous proteomic analyses of human sperm. These findings suggest that the reproductive functions of ADAM2 differ between humans and mice. Our protein analysis showed the presence of potential ADAM2 complexes involving yet-unknown proteins in human testis. Taken together, our results provide new information regarding the characteristics of ADAM2 in mammalian species, including humans. PMID:27341348

  17. The T4 phage DNA mimic protein Arn inhibits the DNA binding activity of the bacterial histone-like protein H-NS.

    PubMed

    Ho, Chun-Han; Wang, Hao-Ching; Ko, Tzu-Ping; Chang, Yuan-Chih; Wang, Andrew H-J

    2014-09-26

    The T4 phage protein Arn (Anti restriction nuclease) was identified as an inhibitor of the restriction enzyme McrBC. However, until now its molecular mechanism remained unclear. In the present study we used structural approaches to investigate biological properties of Arn. A structural analysis of Arn revealed that its shape and negative charge distribution are similar to dsDNA, suggesting that this protein could act as a DNA mimic. In a subsequent proteomic analysis, we found that the bacterial histone-like protein H-NS interacts with Arn, implying a new function. An electrophoretic mobility shift assay showed that Arn prevents H-NS from binding to the Escherichia coli hns and T4 p8.1 promoters. In vitro gene expression and electron microscopy analyses also indicated that Arn counteracts the gene-silencing effect of H-NS on a reporter gene. Because McrBC and H-NS both participate in the host defense system, our findings suggest that T4 Arn might knock down these mechanisms using its DNA mimicking properties.

  18. Optimal Hydrophobicity in Ring-Opening Metathesis Polymerization-Based Protein Mimics Required for siRNA Internalization.

    PubMed

    deRonde, Brittany M; Posey, Nicholas D; Otter, Ronja; Caffrey, Leah M; Minter, Lisa M; Tew, Gregory N

    2016-06-13

    Exploring the role of polymer structure for the internalization of biologically relevant cargo, specifically siRNA, is of critical importance to the development of improved delivery reagents. Herein, we report guanidinium-rich protein transduction domain mimics (PTDMs) based on a ring-opening metathesis polymerization scaffold containing tunable hydrophobic moieties that promote siRNA internalization. Structure-activity relationships using Jurkat T cells and HeLa cells were explored to determine how the length of the hydrophobic block and the hydrophobic side chain compositions of these PTDMs impacted siRNA internalization. To explore the hydrophobic block length, two different series of diblock copolymers were synthesized: one series with symmetric block lengths and one with asymmetric block lengths. At similar cationic block lengths, asymmetric and symmetric PTDMs promoted siRNA internalization in the same percentages of the cell population regardless of the hydrophobic block length; however, with 20 repeat units of cationic charge, the asymmetric block length had greater siRNA internalization, highlighting the nontrivial relationships between hydrophobicity and overall cationic charge. To further probe how the hydrophobic side chains impacted siRNA internalization, an additional series of asymmetric PTDMs was synthesized that featured a fixed hydrophobic block length of five repeat units that contained either dimethyl (dMe), methyl phenyl (MePh), or diphenyl (dPh) side chains and varied cationic block lengths. This series was further expanded to incorporate hydrophobic blocks consisting of diethyl (dEt), diisobutyl (diBu), and dicyclohexyl (dCy) based repeat units to better define the hydrophobic window for which our PTDMs had optimal activity. High-performance liquid chromatography retention times quantified the relative hydrophobicities of the noncationic building blocks. PTDMs containing the MePh, diBu, and dPh hydrophobic blocks were shown to have superior

  19. Cellular roles of ADAM12 in health and disease.

    PubMed

    Kveiborg, Marie; Albrechtsen, Reidar; Couchman, John R; Wewer, Ulla M

    2008-01-01

    ADAM12 belongs to the large family of ADAMs (a disintegrin and metalloproteases) and possesses extracellular metalloprotease and cell-binding functions, as well as intracellular signaling capacities. Interest in ADAM12 has increased recently because its expression is related to tumor progression and it is a potential biomarker for breast cancer. It is therefore important to understand ADAM12's functions. Many cellular roles for ADAM12 have been suggested. It is an active metalloprotease, and has been implicated in insulin-like growth factor (IGF) receptor signaling, through cleavage of IGF-binding proteins, and in epidermal growth factor receptor (EGFR) pathways, via ectodomain shedding of membrane-tethered EGFR ligands. These proteolytic events may regulate diverse cellular responses, such as altered cell differentiation, proliferation, migration, and invasion. ADAM12 may also regulate cell-cell and cell-extracellular matrix contacts through interactions with cell surface receptors - integrins and syndecans - potentially influencing the actin cytoskeleton. Moreover, ADAM12 interacts with several cytoplasmic signaling and adaptor molecules through its intracellular domain, thereby directly transmitting signals to or from the cell interior. These ADAM12-mediated cellular effects appear to be critical events in both biological and pathological processes. This review presents current knowledge on ADAM12 functions gained from in vitro and in vivo observations, describes ADAM12's role in both normal physiology and pathology, particularly in cancer, and discusses important areas for future investigation.

  20. ADAM10: a new player in breast cancer progression?

    PubMed Central

    Mullooly, Maeve; McGowan, Patricia M; Kennedy, Susan A; Madden, Stephen F; Crown, John; O' Donovan, Norma; Duffy, Michael J

    2015-01-01

    Background: The ADAM proteases are best known for their role in shedding the extracellular domain of transmembrane proteins. Among the transmembrane proteins shed by ADAM10 are notch, HER2, E-cadherin, CD44, L1 and the EGFR ligands, EGF and betacellulin. As cleavage of several of these proteins has been implicated in cancer formation and progression, we hypothesised that ADAM10 is also involved in these processes. Methods: ADAM10 expression was decreased by RNA interference and the effects of this on cell numbers, invasion and migration were determined. We also examined the effect of ADAM10 inhibition on breast cancer cell line invasion and migration. Results: Using the triple-negative (TN) breast cancer cell lines, BT20, MDA-MB-231 and the non-TN cell line MDA-MB-453, knockdown of ADAM10 expression significantly decreased in vitro migration (P<0.01; for each cell line). Similarly, treatment with the ADAM10-selective inhibitor GI254023X reduced migration in the three cell lines (for BT20, P<0.001; for MDA-MB-231, P=0.005; for MDA-MB-453, P=0.023). In contrast, neither knockdown of ADAM10 nor treatment with the ADAM10-selective inhibitor GI254023X significantly affected cell numbers. Using extracts of primary breast cancers, higher levels of ADAM10 were found more frequently in high-grade vs low-grade tumours (P<0.001) and in oestrogen receptor (ER)-negative compared with ER-positive tumours (P=0.005). Analysis of pooled publicly available data sets found that high levels of ADAM10 mRNA were associated with adverse outcome in patients with the basal subtype of breast cancer. Conclusions: Based on our combined cell line and breast cancer extract data, we conclude that ADAM10 is likely to be involved in breast cancer progression, especially in the basal subtype. PMID:26284334

  1. Ansel Adams: early works

    NASA Astrophysics Data System (ADS)

    Throckmorton, Jodi

    2010-02-01

    Ansel Adams (1902-1984), photographer, musician, naturalist, explorer, critic, and teacher, was a giant in the field of landscape photography. In his images of the unspoiled Western landscape, he strove to capture the sublime: the transcendentalist concept that nature can generate the experience of awe for the viewer. Many viewers are familiar with the heroic, high-contrast prints on high-gloss paper that Adams made to order beginning in the 1970s; much less well known are the intimate prints that the artist crafted earlier in his career. This exhibition focuses on these masterful small prints from the 1920s into the 1950s. During this time period, Adams's printing style changed dramatically. The painterly, soft-focus, warm-toned style of the Parmelian Prints of the High Sierras from the 1920s evolved into the sharp-focus style of the f/64 school of photography that Adams co-founded in the 1930s with Edward Weston and Imogen Cunningham. After World War II, Adams opted for a cooler, higher-contrast look for his prints. Throughout the various styles in which he chose to work, Adams explored the power of nature and succeeded in establishing landscape photography as a legitimate form of modern art.

  2. The ADAMs family of proteases: new biomarkers and therapeutic targets for cancer?

    PubMed Central

    2011-01-01

    The ADAMs are transmembrane proteins implicated in proteolysis and cell adhesion. Forty gene members of the family have been identified, of which 21 are believed to be functional in humans. As proteases, their main substrates are the ectodomains of other transmembrane proteins. These substrates include precursor forms of growth factors, cytokines, growth factor receptors, cytokine receptors and several different types of adhesion molecules. Although altered expression of specific ADAMs has been implicated in different diseases, their best-documented role is in cancer formation and progression. ADAMs shown to play a role in cancer include ADAM9, ADAM10, ADAM12, ADAM15 and ADAM17. Two of the ADAMs, i.e., ADAM10 and 17 appear to promote cancer progression by releasing HER/EGFR ligands. The released ligands activate HER/EGFR signalling that culminates in increased cell proliferation, migration and survival. Consistent with a causative role in cancer, several ADAMs are emerging as potential cancer biomarkers for aiding cancer diagnosis and predicting patient outcome. Furthermore, a number of selective ADAM inhibitors, especially against ADAM10 and ADAM17, have been shown to have anti-cancer effects. At least one of these inhibitors is now undergoing clinical trials in patients with breast cancer. PMID:21906355

  3. Suppression of tunicamycin-induced CD44v6 ectodomain shedding and apoptosis is correlated with temporal expression patterns of active ADAM10, MMP-9 and MMP-13 proteins in Caki-2 renal carcinoma cells.

    PubMed

    Kim, Yeoun-Hee; Jung, Jae-Chang

    2012-11-01

    CD44v6 has been shown to coordinate the activation of anti-apoptotic molecules as well as resistance to apoptosis. Here, we investigated CD44v6 ectodomain shedding in Caki-2 human renal carcinoma cells as well as its underlying mechanisms. Exposure of cells to tunicamycin (TM)-induced apoptosis was accompanied by cleavage of caspase-3, PARP-1 and CD44v6 ectodomain. TM-induced apoptosis was also closely associated with endoplasmic reticulum (ER) stress, as shown by increased expression of GRP-78 and CHOP proteins. Furthermore, induction of matrix metallo-proteinase (MMP)-13, MMP-9 and ADAM10 expression was highly stimulated by tunicamycin in a time- and dose-dependent manner. TM-induced PARP-1 cleavage was significantly inhibited by treatment with GM6001 (a broad spectrum MMP inhibitor), MMP-9/-13 inhibitor and GI254023X (specific ADAM10 inhibitor). In addition, inhibition of all examined MMPs resulted in reversal of TM-induced apoptosis as well as increased cell viability. When considering the functional implications of MMP-9 and ADAM10, it is likely that active MMP-9 and ADAM10 help regulate the cellular levels of CD44v6 through cleavage of CD44v6 ectodomain during TM-induced apoptosis of Caki-2 cells. Collectively, these findings suggest that multiple TM-induced MMPs may cooperate to induce apoptosis.

  4. High-Affinity Small-Molecule Inhibitors of the Menin-Mixed Lineage Leukemia (MLL) Interaction Closely Mimic a Natural Protein-Protein Interaction

    SciTech Connect

    He, Shihan; Senter, Timothy J.; Pollock, Jonathan; Han, Changho; Upadhyay, Sunil Kumar; Purohit, Trupta; Gogliotti, Rocco D.; Lindsley, Craig W.; Cierpicki, Tomasz; Stauffer, Shaun R.; Grembecka, Jolanta

    2014-10-02

    The protein–protein interaction (PPI) between menin and mixed lineage leukemia (MLL) plays a critical role in acute leukemias, and inhibition of this interaction represents a new potential therapeutic strategy for MLL leukemias. We report development of a novel class of small-molecule inhibitors of the menin–MLL interaction, the hydroxy- and aminomethylpiperidine compounds, which originated from HTS of ~288000 small molecules. We determined menin–inhibitor co-crystal structures and found that these compounds closely mimic all key interactions of MLL with menin. Extensive crystallography studies combined with structure-based design were applied for optimization of these compounds, resulting in MIV-6R, which inhibits the menin–MLL interaction with IC50 = 56 nM. Treatment with MIV-6 demonstrated strong and selective effects in MLL leukemia cells, validating specific mechanism of action. Our studies provide novel and attractive scaffold as a new potential therapeutic approach for MLL leukemias and demonstrate an example of PPI amenable to inhibition by small molecules.

  5. ADAM12 and ADAM17 gene expression in laser-capture microdissected and non-microdissected breast tumors.

    PubMed

    Narita, Diana; Seclaman, Edward; Ilina, Razvan; Cireap, Natalia; Ursoniu, Sorin; Anghel, Andrei

    2011-06-01

    ADAM (a disintegrin and metalloprotease)12 and ADAM17 are multidomain transmembrane proteins involved in ectodomain shedding of cytokines, growth factors and adhesion molecules, with pivotal activities in the tumor microenvironment. The aim of this study was to confirm the up-regulation of ADAM17 and ADAM12 gene splicing variants in breast tumors and to delineate their expression between laser-capture microdissected (LCM) and non-microdissected breast tumors. The gene expression was analyzed by quantitative-reverse transcription-PCR in a total sample of 109 breast tumors paired with corresponding non-neoplastic breast tissues. ADAM12 and 17 proteins expression for corresponding tissue samples was confirmed by immunohistochemistry. ADAM12S, 12L and 17 genes were significantly up-regulated in either malign or benign LCM samples when compared to non-tumor controls. For non-LCM samples, it was obtained also an increased expression for ADAM12 and 17 genes in cancers, while in benign tumors only ADAM12 variants were significantly up-regulated compared to controls. When benign versus malignant tumors were compared, in LCM samples all investigated genes displayed a higher expression in cancers, whereas in non-LCM, ADAM12 variants were overexpressed in benign samples. The increased expression of ADAM12 protein in the tumor cells and stroma of benign breast diseases was immunohistochemically confirmed. These differences between LCM and non-LCM samples were explained by the contribution of the stroma to the expression of this marker. This study underlines the accuracy conferred by homogenous LCM samples on gene expression profiles and confers further evidence regarding the role of ADAM12 and 17 in the breast tumorigenesis and progression.

  6. A Substrate Mimic Allows High-Throughput Assay of the FabA Protein and Consequently the Identification of a Novel Inhibitor of Pseudomonas aeruginosa FabA

    PubMed Central

    Moynié, Lucile; Hope, Anthony G.; Finzel, Kara; Schmidberger, Jason; Leckie, Stuart M.; Schneider, Gunter; Burkart, Michael D.; Smith, Andrew D.; Gray, David W.; Naismith, James H.

    2016-01-01

    Eukaryotes and prokaryotes possess fatty acid synthase (FAS) biosynthetic pathways that comprise iterative chain elongation, reduction, and dehydration reactions. The bacterial FASII pathway differs significantly from human FAS pathways and is a long-standing target for antibiotic development against Gram-negative bacteria due to differences from the human FAS, and several existing antibacterial agents are known to inhibit FASII enzymes. N-Acetylcysteamine (NAC) fatty acid thioesters have been used as mimics of the natural acyl carrier protein pathway intermediates to assay FASII enzymes, and we now report an assay of FabV from Pseudomonas aeruginosa using (E)-2-decenoyl-NAC. In addition, we have converted an existing UV absorbance assay for FabA, the bifunctional dehydration/epimerization enzyme and key target in the FASII pathway, into a high-throughput enzyme coupled fluorescence assay that has been employed to screen a library of diverse small molecules. With this approach, N-(4-chlorobenzyl)-3-(2-furyl)-1H-1,2,4-triazol-5-amine (N42FTA) was found to competitively inhibit (pIC50 = 5.7 ± 0.2) the processing of 3-hydroxydecanoyl-NAC by P. aeruginosa FabA. N42FTA was shown to be potent in blocking crosslinking of Escherichia coli acyl carrier protein and FabA, a direct mimic of the biological process. The co-complex structure of N42FTA with P. aeruginosa FabA protein rationalises affinity and suggests future design opportunities. Employing NAC fatty acid mimics to develop further high-throughput assays for individual enzymes in the FASII pathway should aid in the discovery of new antimicrobials. PMID:26562505

  7. ADAM -- Interface Module Reference Manual

    NASA Astrophysics Data System (ADS)

    Chipperfield, A. J.; Kelly, B. D.; Wright, S. L.

    ADAM Interface Modules provide an interface between ADAM application programs and the rest of the system. This document describes in detail the facilities available with ADAM Interface Modules and the rules for using them. It is intended as a reference manual and should shed light on some of the finer points of the ADAM parameter system. Readers requiring an introduction to Interface Modules should read SG/4.

  8. Reversible non-stick behaviour of a bacterial protein polymer provides a tuneable molecular mimic for cell and tissue engineering.

    PubMed

    Roque, Ana I; Soliakov, Andrei; Birch, Mark A; Philips, Sion R; Shah, Deepan S H; Lakey, Jeremy H

    2014-05-01

    Yersina pestis, the bubonic plague bacterium, is coated with a polymeric protein hydrogel for protection from host defences. The protein, which is robust and non-stick, resembles structures found in many eukaryotic extracellular-matrix proteins. Cells grown on the natural polymer cannot adhere and grow poorly; however, when cell-adhesion motifs are inserted into the protein, the cells proliferate.

  9. Was Adam a Real Person?

    ERIC Educational Resources Information Center

    Lamoureux, Denis O.

    2011-01-01

    Belief in the historicity of Adam has been held firmly throughout the history of the church. In the light of modern biblical criticism and the evolutionary sciences, some conservative Christians are now questioning whether or not Adam was a real person. This paper argues that the existence of Adam in the opening chapters of scripture reflects an…

  10. All about Adam.

    ERIC Educational Resources Information Center

    Bradley, Ann

    1992-01-01

    Rochester Teachers Association President Adam Urbanski is kingpin of a new breed of union leaders who want to be partners, not adversaries, in the school improvement crusade. Despite his good intentions, many people in his hometown are disgruntled with him. The article describes his work over the past five years. (SM)

  11. The Adams Family

    ERIC Educational Resources Information Center

    Douven, Igor; Verbrugge, Sara

    2010-01-01

    According to Adams's Thesis, the acceptability of an indicative conditional sentence goes by the conditional probability of its consequent given its antecedent. We test, for the first time, whether this thesis is descriptively correct and show that it is not; in particular, we show that it yields the wrong predictions for people's judgments of the…

  12. Adams v. State.

    PubMed

    1998-01-01

    The Supreme Court of Georgia, on 4 May 1998, held that a state statute permitting a crime victim who is significantly exposed to HIV request an HIV blood test on the person charged with the crime and arrested does not violate the Fourth Amendment right against unreasonable searches, nor does it violate privacy or equal protection rights. Malik Adams attacked and struggled with police officers during arrest. In the struggle, Adams's and an officer's hands, on which there were bleeding wounds, came in contact. Even though Adams did not have any outward AIDS symptoms, the State filed a motion to compel HIV testing. The Supreme Court of Georgia held that, because the statute compelling HIV testing serves the compelling state interest of preventing the public's exposure to HIV, the search, in this case the taking and sampling of blood, was reasonable. The statute also did not violate Adams's right to privacy or state or federal equal protection clauses. The judgment of the Superior court was affirmed.

  13. Adams v. State.

    PubMed

    1998-01-01

    Court Decision: 498 South Eastern Reporter, 2d Series 268; 1998 May 4 (date of decision). The Supreme Court of Georgia held that a state statute permitting a crime victim who is significantly exposed to HIV request an HIV blood test on the person charged with the crime and arrested does not violate the Fourth Amendment right against unreasonable searches, nor does it violate privacy or equal protection rights. Malik Adams attacked and struggled with police officers during arrest. In the struggle, Adams's and an officer's hands, on which there were bleeding wounds, came in contact. Even though Adams did not have any outward AIDS symptoms, the State filed a motion to compel HIV testing. The Supreme Court of Georgia held that, because the statute compelling HIV testing serves the compelling state interest of preventing the public's exposure to HIV, the search, in this case the taking and sampling of blood, was reasonable. The statute also did not violate Adams's right to privacy or state or federal equal protection clauses.

  14. Reconstituting redox active centers of heme-containing proteins with biomineralized gold toward peroxidase mimics with strong intrinsic catalysis and electrocatalysis for H2O2 detection.

    PubMed

    Zhang, Liyan; Li, Shuai; Dong, Minmin; Jiang, Yao; Li, Ru; Zhang, Shuo; Lv, Xiaoxia; Chen, Lijun; Wang, Hua

    2017-01-15

    A facile and efficient enzymatic reconstitution methodology has been proposed for high-catalysis peroxidase mimics by remolding the redox active centers of heme-containing proteins with the in-site biomineralized gold using hemoglobin (Hb) as a model. Catalytic hemin (Hem) was extracted from the active centers of Hb for the gold biomineralization and then reconstituted into apoHb to yield the Hem-Au@apoHb nanocomposites showing dramatically improved intrinsic catalysis and electrocatalysis over natural Hb and Hem. The biomineralized gold, on the one hand, would act as "nanowires" to promote the electron transferring of the nanocomposites. On the other hand, it would create a reactivity pathway to pre-organize and accumulate more substrates towards the active sites of the peroxidase mimics. Steady-state kinetics studies indicate that Hem-Au@apoHb could present much higher substrate affinity (lower Michaelis constants) and intrinsic catalysis even than some natural peroxidases. Moreover, the application feasibility of the prepared artificial enzymes was demonstrated by colorimetric assays and direct electrocatalysis for H2O2 sensing, showing a detection limitation low as 0.45μM. Importantly, such a catalysis active-center reconstitution protocol may circumvent the substantial improvement of the intrinsic catalysis and electrocatalysis of diverse heme-containing proteins or enyzmes toward the extensive applications in the chemical, enviromental, and biomedical catalysis fields.

  15. Connective tissue growth factor is a substrate of ADAM28

    SciTech Connect

    Mochizuki, Satsuki; Tanaka, Rena; Shimoda, Masayuki; Onuma, Junko; Fujii, Yutaka; Jinno, Hiromitsu; Okada, Yasunori

    2010-11-26

    Research highlights: {yields} The hyper-variable region in the cysteine-rich domain of ADAM28 binds to C-terminal domain of CTGF. {yields} ADAM28 cleaves CTGF alone and CTGF in the CTGF/VEGF{sub 165} complex. {yields} CTGF digestion by ADAM28 releases biologically active VEGF{sub 165} from the complex. {yields} ADAM28, CTGF and VEGF{sub 165} are commonly co-expressed by carcinoma cells in human breast carcinoma tissues. {yields} These suggest that ADAM28 promotes VEGF{sub 165}-induced angiogenesis in the breast carcinomas by selective CTGF digestion in the CTGF/VEGF{sub 165} complex. -- Abstract: ADAM28, a member of the ADAM (a disintegrin and metalloproteinase) gene family, is over-expressed by carcinoma cells and the expression correlates with carcinoma cell proliferation and progression in human lung and breast carcinomas. However, information about substrates of ADAM28 is limited. We screened interacting molecules of ADAM28 in human lung cDNA library by yeast two-hybrid system and identified connective tissue growth factor (CTGF). Binding of CTGF to proADAM28 was demonstrated by yeast two-hybrid assay and protein binding assay. ADAM28 cleaved CTGF in dose- and time-dependent manners at the Ala{sup 181}-Tyr{sup 182} and Asp{sup 191}-Pro{sup 192} bonds in the hinge region of the molecule. ADAM28 selectively digested CTGF in the complex of CTGF and vascular endothelial growth factor{sub 165} (VEGF{sub 165}), releasing biologically active VEGF{sub 165} from the complex. RT-PCR and immunohistochemical analyses demonstrated that ADAM28, CTGF and VEGF are commonly co-expressed in the breast carcinoma tissues. These data provide the first evidence that CTGF is a novel substrate of ADAM28 and suggest that ADAM28 may promote VEGF{sub 165}-induced angiogenesis in the breast carcinomas by the CTGF digestion in the CTGF/VEGF{sub 165} complex.

  16. Direct measurement of the protein response to an electrostatic perturbation that mimics the catalytic cycle in ketosteroid isomerase.

    PubMed

    Jha, Santosh Kumar; Ji, Minbiao; Gaffney, Kelly J; Boxer, Steven G

    2011-10-04

    Understanding how electric fields and their fluctuations in the active site of enzymes affect efficient catalysis represents a critical objective of biochemical research. We have directly measured the dynamics of the electric field in the active site of a highly proficient enzyme, Δ(5)-3-ketosteroid isomerase (KSI), in response to a sudden electrostatic perturbation that simulates the charge displacement that occurs along the KSI catalytic reaction coordinate. Photoexcitation of a fluorescent analog (coumarin 183) of the reaction intermediate mimics the change in charge distribution that occurs between the reactant and intermediate state in the steroid substrate of KSI. We measured the electrostatic response and angular dynamics of four probe dipoles in the enzyme active site by monitoring the time-resolved changes in the vibrational absorbance (IR) spectrum of a spectator thiocyanate moiety (a quantitative sensor of changes in electric field) placed at four different locations in and around the active site, using polarization-dependent transient vibrational Stark spectroscopy. The four different dipoles in the active site remain immobile and do not align to the changes in the substrate electric field. These results indicate that the active site of KSI is preorganized with respect to functionally relevant changes in electric fields.

  17. Tetraspanin15 regulates cellular trafficking and activity of the ectodomain sheddase ADAM10.

    PubMed

    Prox, Johannes; Willenbrock, Michael; Weber, Silvio; Lehmann, Tobias; Schmidt-Arras, Dirk; Schwanbeck, Ralf; Saftig, Paul; Schwake, Michael

    2012-09-01

    A disintegrin and metalloproteinase10 (ADAM10) has been implicated as a major sheddase responsible for the ectodomain shedding of a number of important surface molecules including the amyloid precursor protein and cadherins. Despite a well-documented role of ADAM10 in health and disease, little is known about the regulation of this protease. To address this issue we conducted a split-ubiquitin yeast two-hybrid screen to identify membrane proteins that interact with ADAM10. The yeast experiments and co-immunoprecipitation studies in mammalian cell lines revealed tetraspanin15 (TSPAN15) to specifically associate with ADAM10. Overexpression of TSPAN15 or RNAi-mediated knockdown of TSPAN15 led to significant changes in the maturation process and surface expression of ADAM10. Expression of an endoplasmic reticulum (ER) retention mutant of TSPAN15 demonstrated an interaction with ADAM10 already in the ER. Pulse-chase experiments confirmed that TSPAN15 accelerates the ER-exit of the ADAM10-TSPAN15 complex and stabilizes the active form of ADAM10 at the cell surface. Importantly, TSPAN15 also showed the ability to mediate the regulation of ADAM10 protease activity exemplified by an increased shedding of N-cadherin and the amyloid precursor protein. In conclusion, our data show that TSPAN15 is a central modulator of ADAM10-mediated ectodomain shedding. Therapeutic manipulation of its expression levels may be an additional approach to specifically regulate the activity of the amyloid precursor protein alpha-secretase ADAM10.

  18. Molecular profiling of ADAM12 gene in breast cancers.

    PubMed

    Nariţa, Diana; Anghel, A; Seclaman, E; Ilina, R; Cireap, Natalia; Ursoniu, S

    2010-01-01

    ADAMs (a disintegrin and metalloproteinase) family have been associated with the process of proteolytic "shedding" of membrane-associated proteins ectodomain and hence the rapid modulation of key cell signaling pathways in tissues microenvironment. A variety of cytokines, chemokines and growth factors which are initially produced as transmembrane proforms are activated by these sheddase activities. ADAM12 is highly expressed in rapidly growing tissues such as placenta and malignant tumors and it was found as one of the Candidate Cancer Genes in a comprehensive mutational analysis of human breast cancers. Our aim was to determine the gene expression profile of ADAM12 in breast cancers in comparison with normal breast and to correlate their level of expression with the clinical and pathological characteristics of breast cancers. Gene expression of ADAM12 spliced variants (12L and 12S) was evaluated using quantitative reverse-transcription PCR in samples obtained by laser capture microdissection from 38 patients with breast cancers and compared with adjacent healthy breast tissues. Both ADAM12L and 12S expression were significantly up-regulated in breast cancers, while in the normal breast, we found a very low expression. ADAM12L expression was significantly correlated with the histopathological types and, although not statistically significant, ADAM12 both variants were up-regulated in high-grade, highly-proliferative and HER2÷neu positive tumors. From these preliminary results, we found that ADAM12 could be an interesting marker and eventually a therapeutic target for breast cancer.

  19. Altered expression of zinc finger proteins, ADAMs, and integrin-related proteins following treatment of cultured human cells with a low concentration of N-methyl-N'-nitro-N-nitrosoguanidine.

    PubMed

    Jin, Jinghua; Gao, Zhihua; Guo, Lei; Yang, Jun; Yu, Yingnian

    2003-01-01

    Proteomic analysis is an important approach to characterize the proteome and study protein functions. It is also a powerful screening method for detecting unexpected alterations in protein expression that may be overlooked by conventional biochemical techniques. N-Methyl-N'-nitro-N-nitrosoguanidine (MNNG) is an alkylating agent that can induce nontargeted mutagenesis in treated cells, although the mechanism remains unclear. Using an efficient proteomic method, we identified several cellular proteins that are responsive to low-concentration MNNG treatment in human FL cells. After MNNG treatment, whole cellular proteins were separated using two-dimensional gel electrophoresis and visualized by silver staining; the digitized images then were analyzed with 2D analysis software. More than 60 proteins showed significant changes in MNNG-treated cells compared to control cells (DMSO treatment). Thirty-one proteins only detected in MNNG-treated or control cells were subjected to in-gel digestion with trypsin and identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry using peptide mass fingerprinting. Eighteen of theses proteins have been identified, including several zinc finger proteins, two members of the ADAMs (a disintegrin and metalloprotease domain) family, and two integrins. Most of these proteins have unknown functions and their involvement in the cellular responses to alkylating agents have not been reported. Therefore, our findings may offer new insights into the mechanisms of low-concentration MNNG-induced nontargeted mutagenesis and these proteins may serve as new biomarkers for detecting exposure of human populations to environmental carcinogens.

  20. Cell-surface metalloprotease ADAM12 is internalized by a clathrin- and Grb2-dependent mechanism.

    PubMed

    Stautz, Dorte; Leyme, Anthony; Grandal, Michael Vibo; Albrechtsen, Reidar; van Deurs, Bo; Wewer, Ulla; Kveiborg, Marie

    2012-11-01

    ADAM12 (A Disintegrin And Metalloprotease 12), a member of the ADAMs family of transmembrane proteins, is involved in ectodomain shedding, cell-adhesion and signaling, with important implications in cancer. Therefore, mechanisms that regulate the levels and activity of ADAM12 at the cell-surface are possibly crucial in these contexts. We here investigated internalization and subsequent recycling or degradation of ADAM12 as a potentially important regulatory mechanism. Our results show that ADAM12 is constitutively internalized primarily via the clathrin-dependent pathway and is subsequently detected in both early and recycling endosomes. The protease activity of ADAM12 does not influence this internalization mechanism. Analysis of essential elements for internalization established that proline-rich regions in the cytoplasmic domain of ADAM12, previously shown to interact with Src-homology 3 domains, were necessary for proper internalization. These sites in the ADAM12 cytoplasmic domain interacted with the adaptor protein growth factor receptor-bound protein 2 (Grb2) and knockdown of Grb2 markedly reduced ADAM12 internalization. These studies establish that internalization is indeed a mechanism that regulates ADAM cell surface levels and show that ADAM12 internalization involves the clathrin-dependent pathway and Grb2.

  1. DNA mimics a self-protein that may be a target for some anti-DNA antibodies in systemic lupus erythematosus.

    PubMed

    Zack, D J; Yamamoto, K; Wong, A L; Stempniak, M; French, C; Weisbart, R H

    1995-02-15

    Recent studies suggest that some anti-DNA Abs in systemic lupus erythematosus may actually be Abs to specific proteins and that binding to dsDNA is a nonspecific cross-reactive event. To identify such proteins that bind to anti-DNA Abs, a cDNA expression library from human placenta was screened with mAb 3E10, a pathogenic anti-dsDNA Ab. MAb 3E10 was shown to bind to a 44-amino-acid fragment of HP8, a newly identified protein with amino acid sequence homology to the family of SPARC extracellular matrix proteins. To determine if Ab binding to both dsDNA and HP8 protein occurs through a common binding site, and therefore represents molecular mimicry, the Ab binding domains for protein and DNA were mapped. Chain recombinations between mAb 3E10 and a non-anti-DNA mAb showed that both the heavy and the light chains of mAb 3E10 were essential for anti-dsDNA and anti-HP8 reactivity. Mutagenesis experiments demonstrated that dsDNA and HP8 shared several critical binding residues located in all three complementarity-determining regions of mAb 3E10 VH. Moreover, Abs to HP8 were demonstrated in the sera of a subset of lupus patients. These results indicate that DNA mimics the HP8 protein in binding a lupus Ab, and that this protein may be a target for a subpopulation of anti-dsDNA Abs in systemic lupus erythematosus.

  2. Novel Gbeta Mimic Kelch Proteins Gpb1 and Gpb2 Connect G-Protein Signaling to Ras via Yeast Neurofibromin Homologs Ira 1 and Ira 2: A Model for Human NF1

    DTIC Science & Technology

    2006-03-01

    Furthermore, dele- tion of other known Gpa2 associated proteins, namely the GPCR Gpr1 or the G# subunit mimic Gpg1, or even the elimination of multiple...5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME (S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER Duke University Medical...Center Durham, NC 27710 9. SPONSORING / MONITORING AGENCY NAME (S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) U.S. Army Medical

  3. Peptide–oligonucleotide conjugates as nanoscale building blocks for assembly of an artificial three-helix protein mimic

    PubMed Central

    Lou, Chenguang; Martos-Maldonado, Manuel C.; Madsen, Charlotte S.; Thomsen, Rasmus P.; Midtgaard, Søren Roi; Christensen, Niels Johan; Kjems, Jørgen; Thulstrup, Peter W.; Wengel, Jesper; Jensen, Knud J.

    2016-01-01

    Peptide-based structures can be designed to yield artificial proteins with specific folding patterns and functions. Template-based assembly of peptide units is one design option, but the use of two orthogonal self-assembly principles, oligonucleotide triple helix and a coiled coil protein domain formation have never been realized for de novo protein design. Here, we show the applicability of peptide–oligonucleotide conjugates for self-assembly of higher-ordered protein-like structures. The resulting nano-assemblies were characterized by ultraviolet-melting, gel electrophoresis, circular dichroism (CD) spectroscopy, small-angle X-ray scattering and transmission electron microscopy. These studies revealed the formation of the desired triple helix and coiled coil domains at low concentrations, while a dimer of trimers was dominating at high concentration. CD spectroscopy showed an extraordinarily high degree of α-helicity for the peptide moieties in the assemblies. The results validate the use of orthogonal self-assembly principles as a paradigm for de novo protein design. PMID:27464951

  4. Peptide-oligonucleotide conjugates as nanoscale building blocks for assembly of an artificial three-helix protein mimic

    NASA Astrophysics Data System (ADS)

    Lou, Chenguang; Martos-Maldonado, Manuel C.; Madsen, Charlotte S.; Thomsen, Rasmus P.; Midtgaard, Søren Roi; Christensen, Niels Johan; Kjems, Jørgen; Thulstrup, Peter W.; Wengel, Jesper; Jensen, Knud J.

    2016-07-01

    Peptide-based structures can be designed to yield artificial proteins with specific folding patterns and functions. Template-based assembly of peptide units is one design option, but the use of two orthogonal self-assembly principles, oligonucleotide triple helix and a coiled coil protein domain formation have never been realized for de novo protein design. Here, we show the applicability of peptide-oligonucleotide conjugates for self-assembly of higher-ordered protein-like structures. The resulting nano-assemblies were characterized by ultraviolet-melting, gel electrophoresis, circular dichroism (CD) spectroscopy, small-angle X-ray scattering and transmission electron microscopy. These studies revealed the formation of the desired triple helix and coiled coil domains at low concentrations, while a dimer of trimers was dominating at high concentration. CD spectroscopy showed an extraordinarily high degree of α-helicity for the peptide moieties in the assemblies. The results validate the use of orthogonal self-assembly principles as a paradigm for de novo protein design.

  5. Peptide-oligonucleotide conjugates as nanoscale building blocks for assembly of an artificial three-helix protein mimic.

    PubMed

    Lou, Chenguang; Martos-Maldonado, Manuel C; Madsen, Charlotte S; Thomsen, Rasmus P; Midtgaard, Søren Roi; Christensen, Niels Johan; Kjems, Jørgen; Thulstrup, Peter W; Wengel, Jesper; Jensen, Knud J

    2016-07-28

    Peptide-based structures can be designed to yield artificial proteins with specific folding patterns and functions. Template-based assembly of peptide units is one design option, but the use of two orthogonal self-assembly principles, oligonucleotide triple helix and a coiled coil protein domain formation have never been realized for de novo protein design. Here, we show the applicability of peptide-oligonucleotide conjugates for self-assembly of higher-ordered protein-like structures. The resulting nano-assemblies were characterized by ultraviolet-melting, gel electrophoresis, circular dichroism (CD) spectroscopy, small-angle X-ray scattering and transmission electron microscopy. These studies revealed the formation of the desired triple helix and coiled coil domains at low concentrations, while a dimer of trimers was dominating at high concentration. CD spectroscopy showed an extraordinarily high degree of α-helicity for the peptide moieties in the assemblies. The results validate the use of orthogonal self-assembly principles as a paradigm for de novo protein design.

  6. Myxoma Virus Immunomodulatory Protein M156R is a Structural Mimic of Eukaryotic Translation Initiation Factor eIF2 alpha

    SciTech Connect

    Ramelot, Theresa A.; Cort, John R.; Yee, Adelinda; Liu, Furong; Goshe, Michael B.; Edwards, Aled M.; Smith, Richard D.; Arrowsmith, Cheryl H.; Dever, Thomas E.; Kennedy, Michael A.

    2002-10-04

    M156R, the product of the myxoma virus M156R open reading frame, is a protein of unknown function. However, several homologs of M156R from other viruses are immunomodulatory proteins that bind to interferon-induced protein kinase PKR and inhibit phosphorylation of the eukaryotic translation initiation factor eIF2a. In this study, we have determined the nuclear magnetic resonance (NMR) structure of M156R, the first structure of a myxoma virus protein. The fold consists of a five-stranded antiparallel b-barrel with two of the strands connected by a long loop and a short a-helix. The similarity between M156R and the predicted S1 motif structure of eIF2a suggests that the viral homologs are pseudosubstrate inhibitors of PKR that mimic eIF2a in order to compete for binding to PKR. A homology modeled structure of the well studied vaccinia virus K3L was generated based on alignment with M156R. Residues important for binding to PKR are conserved residues on the surface of the b-barrel and in the mobile loop, identifying the putative PKR recognition motif.

  7. Essential role of eIF5-mimic protein in animal development is linked to control of ATF4 expression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Translational control of ATF4 through upstream ORFs (uORFs) plays an important role in eukaryotic gene regulation. While ATF4 translation is typically induced by inhibitory phosphorylation of eIF2, ATF4 translation can be also induced by expression of a new translational inhibitor protein, eIF5-mimi...

  8. Nonpolar substitution at C-terminus of the prion protein, a mimic of GPI anchor, partially impairs amyloid fibrils formation

    PubMed Central

    Breydo, Leonid; Sun, Ying; Makarava, Natallia; Lee, Cheng-I; Novitskaia, Vera; Bocharova, Olga; Kao, Joseph P.Y.; Baskakov, Ilia V.

    2008-01-01

    In contrast to most amyloidogenic proteins or peptides that do not contain any significant post-translational modifications, the prion protein (PrP) is modified with either one or two polysaccharides and a GPI anchor which attaches PrP to the plasma membrane. Like other amyloidogenic proteins, however, PrP adopts a fibrillar shape when converted to a disease-specific conformation. Therefore, PrP polymerization offers a unique opportunity to examine the effects of biologically relevant non-peptidic modifications on conversion to the amyloid conformation. To test the extent to which a long hydrophobic chain at the C-terminus affects the intrinsic amyloidogenic propensity of PrP, we modified recombinant PrP with a N-myristoylamido-maleimidyl group, which can serve as a membrane anchor. We show that while this modification increases the affinity of PrP for the cell membrane, it does not alter the structure of the protein. Myristoylation of PrP affected amyloid formation in two ways: (i) it substantially decreased the extent of fibrillation, presumably due to off-pathway aggregation, and (ii) it prohibited assembly of filaments into higher-order fibrils by preventing their lateral association. The negative effect on lateral association was abolished if the myristoylated moiety at the C-terminus was replaced by a polar group of similar size or by a hydrophobic group of smaller size. When preformed PrP fibrils were provided as seeds, myristoylated PrP supported fibril elongation and formation of higher-order fibrils composed of several filaments. Our studies illustrate that, despite a bulky hydrophobic moiety at C-terminus, myristoylated PrP can still incorporate into fibrillar structure, and that the C-terminal hydrophobic substitution does not affect the size of the proteinase K resistant core, but controls the mode of lateral assembly of filaments into higher-order fibrils. PMID:17223707

  9. Phosphorylated, cellulose-based substrates as potential adsorbents for bone morphogenetic proteins in biomedical applications: a protein adsorption screening study using cytochrome C as a bone morphogenetic protein mimic.

    PubMed

    Mucalo, Michael R; Kato, Katsuya; Yokogawa, Yoshiyuki

    2009-06-01

    Screening studies aimed at identifying useful biomedical materials that (when combined with implants) can attract bone morphogenetic proteins to their surfaces have been conducted. In this paper, the screening process has involved carrying out protein adsorption studies using cytochrome C, as a BMP protein mimic on phosphorylated cellulose-based substrates. These studies have shown that phosphorylation of cellulose produces materials that are capable of attracting the adsorption of cytochrome C to their surface. In contrast, negligible cytochrome C adsorption was observed on the unphosphorylated cellulose-based materials. The selective uptake of the positively charged cytochrome C (from solutions at pH 9.51) by the negatively charged phosphorylated cotton and microcrystalline cellulose substrates was primarily due to this protein's high isoelectric point (i.e.p) of 9.8 which gives it a positive charge at pHprotein adsorption behaviour, this property with respect to phosphorylated materials and its potential use for selective BMP adsorption onto biomedical materials, have not been reported directly in the literature. The work thus shows that the phosphorylated cellulose-based substrates should be seriously considered as carrier materials that could be used (with preloaded BMPs) as part of an implant system to assist in implant healing.

  10. New Mathematical Dimensions: Adam's Story

    ERIC Educational Resources Information Center

    Manizade, Agida

    2009-01-01

    Adam, an 11th grader, was identified as gifted and accepted into a two week summer enrichment program. He signed up for "Geometry with Flash Programming." He had no prior programming experience but had a strong and healthy self-image as mathematics student. Although Adam had a positive attitude toward mathematics and saw himself as a successful…

  11. Medial prefrontal cortical injections of c-fos antisense oligonucleotides transiently lower c-Fos protein and mimic amphetamine withdrawal behaviours.

    PubMed

    Persico, A M; Schindler, C W; Davis, S C; Ambrosio, E; Uhl, G R

    1998-02-01

    Prefrontal cerebral cortical areas display decreased expression of several transcription factor/immediate-early genes, including c-fos, during amphetamine withdrawal. Antisense strategies can help to test possible roles for this prefrontal c-fos down-regulation in the behavioural correlates of amphetamine withdrawal. Medial prefrontal cortical injections delivering 1.7 nmoles of anti c-fos oligonucleotides revealed an approximately 3 h half-life for phosphothioate and a 15 min half-life for phosphodiester oligonucleotides. Antisense phosphothioates complementary to the c-fos translational start site reduced levels of c-Fos protein, while exerting modest and variable effects on c-fos messenger RNA levels. Neither missense phosphorothioate nor antisense phosphodiester oligonucleotides significantly reduced levels of either c-fos messenger RNA or protein. Animals injected with anti c-fos phosphothioate oligonucleotides into the medial prefrontal cortex displayed marked reductions in linear locomotor activity and repetitive movements measured in a novel environment, effects not seen when missense oligonucleotides were used or when animals were accustomed to the activity monitor prior to antisense oligonucleotide injection. Behavioural changes produced by prefrontal cortical injections of c-fos antisense oligonucleotides closely mimic alterations recorded during amphetamine withdrawal. Prefrontal c-fos could thus conceivably play roles in the neurobiological underpinnings of psychostimulant withdrawal and of responses to stressors such as exposure to novel environments.

  12. Simultaneous recognition of HIV-1 TAR RNA bulge and loop sequences by cyclic peptide mimics of Tat protein

    SciTech Connect

    Davidson, Amy; Leeper, Thomas C.; Athanassiou, Zafiria; Patora-Komisarska, Krystyna; Karn, Jonathan; Robinson, John A.; Varani, Gabriele

    2009-07-21

    The interaction of the HIV-1 transactivator protein Tat with its transactivation response (TAR) RNA is an essential step in viral replication and therefore an attractive target for developing antivirals with new mechanisms of action. Numerous compounds that bind to the 3-nt bulge responsible for binding Tat have been identified in the past, but none of these molecules had sufficient potency to warrant pharmaceutical development. We have discovered conformationally-constrained cyclic peptide mimetics of Tat that are specific nM inhibitors of the Tat-TAR interaction by using a structure-based approach. The lead peptides are nearly as active as the antiviral drug nevirapine against a variety of clinical isolates in human lymphocytes. The NMR structure of a peptide–RNA complex reveals that these molecules interfere with the recruitment to TAR of both Tat and the essential cellular cofactor transcription elongation factor-b (P-TEFb) by binding simultaneously at the RNA bulge and apical loop, forming an unusually deep pocket. This structure illustrates additional principles in RNA recognition: RNA-binding molecules can achieve specificity by interacting simultaneously with multiple secondary structure elements and by inducing the formation of deep binding pockets in their targets. It also provides insight into the P-TEFb binding site and a rational basis for optimizing the promising antiviral activity observed for these cyclic peptides.

  13. Parkinson’s Protein α-Synuclein Binds Efficiently and with a Novel Conformation to Two Natural Membrane Mimics

    PubMed Central

    Kumar, Pravin; Segers-Nolten, Ine M. J.; Schilderink, Nathalie; Subramaniam, Vinod; Huber, Martina

    2015-01-01

    Binding of human α-Synuclein, a protein associated with Parkinson’s disease, to natural membranes is thought to be crucial in relation to its pathological and physiological function. Here the binding of αS to small unilamellar vesicles mimicking the inner mitochondrial and the neuronal plasma membrane is studied in situ by continuous wave and pulsed electron paramagnetic resonance. Local binding information of αS spin labeled by MTSL at positions 56 and 69 respectively shows that also helix 2 (residues 50–100) binds firmly to both membranes. By double electron-electron resonance (DEER) on the mutant spin labeled at positions 27 and 56 (αS 27/56) a new conformation on the membrane is found with a distance of 3.6 nm/ 3.7 nm between residues 27 and 56. In view of the low negative charge density of these membranes, the strong interaction is surprising, emphasizing that function and pathology of αS could involve synaptic vesicles and mitochondria. PMID:26588454

  14. Endoplasmic reticulum stress-independent activation of unfolded protein response kinases by a small molecule ATP-mimic

    PubMed Central

    Mendez, Aaron S; Alfaro, Jennifer; Morales-Soto, Marisol A; Dar, Arvin C; McCullagh, Emma; Gotthardt, Katja; Li, Han; Acosta-Alvear, Diego; Sidrauski, Carmela; Korennykh, Alexei V; Bernales, Sebastian; Shokat, Kevan M; Walter, Peter

    2015-01-01

    Two ER membrane-resident transmembrane kinases, IRE1 and PERK, function as stress sensors in the unfolded protein response. IRE1 also has an endoribonuclease activity, which initiates a non-conventional mRNA splicing reaction, while PERK phosphorylates eIF2α. We engineered a potent small molecule, IPA, that binds to IRE1's ATP-binding pocket and predisposes the kinase domain to oligomerization, activating its RNase. IPA also inhibits PERK but, paradoxically, activates it at low concentrations, resulting in a bell-shaped activation profile. We reconstituted IPA-activation of PERK-mediated eIF2α phosphorylation from purified components. We estimate that under conditions of maximal activation less than 15% of PERK molecules in the reaction are occupied by IPA. We propose that IPA binding biases the PERK kinase towards its active conformation, which trans-activates apo-PERK molecules. The mechanism by which partial occupancy with an inhibitor can activate kinases may be wide-spread and carries major implications for design and therapeutic application of kinase inhibitors. DOI: http://dx.doi.org/10.7554/eLife.05434.001 PMID:25986605

  15. Broccoli: rapid selection of an RNA mimic of green fluorescent protein by fluorescence-based selection and directed evolution.

    PubMed

    Filonov, Grigory S; Moon, Jared D; Svensen, Nina; Jaffrey, Samie R

    2014-11-19

    Genetically encoded fluorescent ribonucleic acids (RNAs) have diverse applications, including imaging RNA trafficking and as a component of RNA-based sensors that exhibit fluorescence upon binding small molecules in live cells. These RNAs include the Spinach and Spinach2 aptamers, which bind and activate the fluorescence of fluorophores similar to that found in green fluorescent protein. Although additional highly fluorescent RNA-fluorophore complexes would extend the utility of this technology, the identification of novel RNA-fluorophore complexes is difficult. Current approaches select aptamers on the basis of their ability to bind fluorophores, even though fluorophore binding alone is not sufficient to activate fluorescence. Additionally, aptamers require extensive mutagenesis to efficiently fold and exhibit fluorescence in living cells. Here we describe a platform for rapid generation of highly fluorescent RNA-fluorophore complexes that are optimized for function in cells. This procedure involves selection of aptamers on the basis of their binding to fluorophores, coupled with fluorescence-activated cell sorting (FACS) of millions of aptamers expressed in Escherichia coli. Promising aptamers are then further optimized using a FACS-based directed evolution approach. Using this approach, we identified several novel aptamers, including a 49-nt aptamer, Broccoli. Broccoli binds and activates the fluorescence of (Z)-4-(3,5-difluoro-4-hydroxybenzylidene)-1,2-dimethyl-1H-imidazol-5(4H)-one. Broccoli shows robust folding and green fluorescence in cells, and increased fluorescence relative to Spinach2. This reflects, in part, improved folding in the presence of low cytosolic magnesium concentrations. Thus, this novel fluorescence-based selection approach simplifies the generation of aptamers that are optimized for expression and performance in living cells.

  16. The alpha secretase ADAM10: A metalloprotease with multiple functions in the brain.

    PubMed

    Saftig, Paul; Lichtenthaler, Stefan F

    2015-12-01

    Proteins belonging to the 'A Disintegrin And Metalloproteinase' (ADAM) family are membrane-anchored proteases that are able to cleave the extracellular domains of several membrane-bound proteins in a process known as 'ectodomain shedding'. In the central nervous system, ADAM10 has attracted the most attention, since it was described as the amyloid precursor protein α-secretase over ten years ago. Despite the excitement over the potential of ADAM10 as a novel drug target in Alzheimer disease, the physiological functions of ADAM10 in the brain are not yet well understood. This is largely because of the embryonic lethality of ADAM10-deficient mice, which results from the loss of cleavage and signaling of the Notch receptor, another ADAM10 substrate. However, the recent generation of conditional ADAM10-deficient mice and the identification of further ADAM10 substrates in the brain has revealed surprisingly numerous and fundamental functions of ADAM10 in the development of the embryonic brain and also in the homeostasis of adult neuronal networks. Mechanistically, ADAM10 controls these functions by utilizing unique postsynaptic substrates in the central nervous system, in particular synaptic cell adhesion molecules, such as neuroligin-1, N-cadherin, NCAM, Ephrin A2 and A5. Consequently, a dysregulation of ADAM10 activity is linked to psychiatric and neurological diseases, such as epilepsy, fragile X syndrome and Huntington disease. This review highlights the recent progress in understanding the substrates and function as well as the regulation and cell biology of ADAM10 in the central nervous system and discusses the value of ADAM10 as a drug target in brain diseases.

  17. Functional analysis of a breast cancer-associated mutation in the intracellular domain of the metalloprotease ADAM12.

    PubMed

    Stautz, Dorte; Wewer, Ulla M; Kveiborg, Marie

    2012-01-01

    A recently identified breast cancer-associated mutation in the metalloprotease ADAM12 alters a potential dileucine trafficking signal, which could affect protein processing and cellular localization. ADAM12 belongs to the group of A Disintegrin And Metalloproteases (ADAMs), which are typically membrane-associated proteins involved in ectodomain shedding, cell-adhesion, and signaling. ADAM12 as well as several members of the ADAM family are over-expressed in various cancers, correlating with disease stage. Three breast cancer-associated somatic mutations were previously identified in ADAM12, and two of these, one in the metalloprotease domain and another in the disintegrin domain, were investigated and found to result in protein misfolding, retention in the secretory pathway, and failure of zymogen maturation. The third mutation, p.L792F in the ADAM12 cytoplasmic tail, was not investigated, but is potentially significant given its location within a di-leucine motif, which is recognized as a potential cellular trafficking signal. The present study was motivated both by the potential relevance of this documented mutation to cancer, as well as for determining the role of the di-leucine motif in ADAM12 trafficking. Expression of ADAM12 p.L792F in mammalian cells demonstrated quantitatively similar expression levels and zymogen maturation as wild-type (WT) ADAM12, as well as comparable cellular localizations. A cell surface biotinylation assay demonstrated that cell surface levels of ADAM12 WT and ADAM12 p.L792F were similar and that internalization of the mutant occurred at the same rate and extent as for ADAM12 WT. Moreover, functional analysis revealed no differences in cell proliferation or ectodomain shedding of epidermal growth factor (EGF), a known ADAM12 substrate between WT and mutant ADAM12. These data suggest that the ADAM12 p.L792F mutation is unlikely to be a driver (cancer causing)-mutation in breast cancer.

  18. Involvement of ADAM10 in axonal outgrowth and myelination of the peripheral nerve.

    PubMed

    Jangouk, Parastoo; Dehmel, Thomas; Meyer Zu Hörste, Gerd; Ludwig, Andreas; Lehmann, Helmar C; Kieseier, Bernd C

    2009-12-01

    The disintegrin and metalloproteinase 10 (ADAM10) is a membrane-anchored metalloproteinase with both proteolytic and disintegrin characteristics. Here, we investigate the expression, regulation, and functional role of ADAM10 in axonal outgrowth and myelination of the peripheral nerve. Expression pattern analysis of 11 ADAM family members in co-cultures of rat dorsal root ganglia (DRG) neurons and Schwann cells (SCs) demonstrated the most pronounced mRNA expression for ADAM10. In further studies, ADAM10 was found to be consistently upregulated in DRG-SC co-cultures before the induction of myelination. Neurons as well as SCs widely expressed ADAM10 at the protein level. In neurons, the expression of ADAM10 was exclusively limited to the axons before the induction of myelination. Inhibition of ADAM10 activity by the hydroxamate-based inhibitors GI254023X and GW280264X resulted in a significant decrease in the mean axonal length. These data suggest that ADAM10 represents a prerequisite for myelination, although its activity is not required during the process of myelination itself as demonstrated by expression analysis of myelin protein zero (P0) and Sudan black staining. Hence, during the process of myelin formation, ADAM10 is highly upregulated and appears to be critically involved in axonal outgrowth that is a requirement for myelination in the peripheral nerve.

  19. The Adams family.

    PubMed

    Douven, Igor; Verbrugge, Sara

    2010-12-01

    According to Adams's Thesis, the acceptability of an indicative conditional sentence goes by the conditional probability of its consequent given its antecedent. We test, for the first time, whether this thesis is descriptively correct and show that it is not; in particular, we show that it yields the wrong predictions for people's judgments of the acceptability of important subclasses of the class of inferential conditionals. Experimental results are presented that reveal an interaction effect between, on the one hand, the type of inferential connection between a conditional's antecedent and its consequent and, on the other, the judged acceptability of the conditional in relation to the conditional probability of its consequent given its antecedent. Specifically, these results suggest a family of theses, each pertaining to a different type of conditional, about how conditionals relate to the relevant conditional probabilities.

  20. The role of CDCP1 (CUB domain-containing protein 1) and ADAM12 (a disintegrin and metalloproteinase 12) in ovarian cancer.

    PubMed

    Vlad, Catalin; Kubelac, Paul; Onisim, Andrea; Irimie, Alexandru; Achimas-Cadariu, Patriciu

    2015-01-01

    Ovarian cancer (OC) is the second most common gynecological cancer and the deadliest in industrialized countries, with poor outcomes that indicate an urgent need to provide a greater insight into the molecular mechanisms underlying OC. Insights into the complex tumor microenviroment show that besides tumor islets, OC biomarkers can derive from newly formed blood vessels that have endothelial cells with a different molecular signature in comparison with their normal counterparts. In this view, recent research has been able to highlight promising candidates such as CDCP1 and ADAM12. Our present review summarises their implications in cancer progression with a focus on OC.

  1. Binding Characteristics of Small Molecules that Mimic Nucleocapsid Protein-induced Maturation of Stem-loop-1 of HIV-1 RNA†

    PubMed Central

    Chung, Janet; Ulyanov, Nikolai B.; Guilbert, Christophe; Mujeeb, Anwer; James, Thomas L.

    2010-01-01

    As a retrovirus, the human immunodeficiency virus (HIV-1) packages two copies of the RNA genome as a dimer in the infectious virion. Dimerization is initiated at the dimer initiation site (DIS) which encompasses stem-loop 1 (SL1) in the 5’-UTR of the genome. Study of genomic dimerization has been facilitated by the discovery that short RNA fragments containing SL1 can dimerize spontaneously without any protein factors. Based on the palindromic nature of SL1, a kissing loop model has been proposed. First, a metastable kissing dimer is formed via standard Watson-Crick base pairs and then converted into a more stable extended dimer by the viral nucleocapsid protein (NCp7). This dimer maturation in vitro is believed to mimic initial steps in the RNA maturation in vivo, which is correlated with viral infectivity. We previously discovered a small molecule activator, Lys-Ala-7-amido-4-methylcoumarin (KA-AMC), which facilitates dimer maturation in vitro, and determined aspects of its structure-activity relationship. In this report, we present measurements of the binding affinity of the activators and characterization of their interactions with the SL1 RNA. Guanidinium groups and increasing positive charge on the side chain enhance affinity and activity, but features in the aromatic ring at least partially decouple affinity from activity. Although KA-AMC can bind to multiple structural motifs, NMR study showed KA-AMC preferentially binds to unique structural motifs, such as the palindromic loop and the G-rich internal loop in the SL1 RNA. NCp7 binds to SL1 only an order of magnitude tighter than the best small molecule ligand tested. The study presented here provides guidelines for design of superior small molecule binders to the SL1 RNA that have the potential of being developed as an antiviral by either interfering with SL1-NCp7 interaction at the packaging and/or maturation stages. PMID:20565056

  2. Overexpression of eIF5 or its protein mimic 5MP perturbs eIF2 function and induces ATF4 translation through delayed re-initiation

    PubMed Central

    Kozel, Caitlin; Thompson, Brytteny; Hustak, Samantha; Moore, Chelsea; Nakashima, Akio; Singh, Chingakham Ranjit; Reid, Megan; Cox, Christian; Papadopoulos, Evangelos; Luna, Rafael E.; Anderson, Abbey; Tagami, Hideaki; Hiraishi, Hiroyuki; Slone, Emily Archer; Yoshino, Ken-ichi; Asano, Masayo; Gillaspie, Sarah; Nietfeld, Jerome; Perchellet, Jean-Pierre; Rothenburg, Stefan; Masai, Hisao; Wagner, Gerhard; Beeser, Alexander; Kikkawa, Ushio; Fleming, Sherry D.; Asano, Katsura

    2016-01-01

    ATF4 is a pro-oncogenic transcription factor whose translation is activated by eIF2 phosphorylation through delayed re-initiation involving two uORFs in the mRNA leader. However, in yeast, the effect of eIF2 phosphorylation can be mimicked by eIF5 overexpression, which turns eIF5 into translational inhibitor, thereby promoting translation of GCN4, the yeast ATF4 equivalent. Furthermore, regulatory protein termed eIF5-mimic protein (5MP) can bind eIF2 and inhibit general translation. Here, we show that 5MP1 overexpression in human cells leads to strong formation of 5MP1:eIF2 complex, nearly comparable to that of eIF5:eIF2 complex produced by eIF5 overexpression. Overexpression of eIF5, 5MP1 and 5MP2, the second human paralog, promotes ATF4 expression in certain types of human cells including fibrosarcoma. 5MP overexpression also induces ATF4 expression in Drosophila. The knockdown of 5MP1 in fibrosarcoma attenuates ATF4 expression and its tumor formation on nude mice. Since 5MP2 is overproduced in salivary mucoepidermoid carcinoma, we propose that overexpression of eIF5 and 5MP induces translation of ATF4 and potentially other genes with uORFs in their mRNA leaders through delayed re-initiation, thereby enhancing the survival of normal and cancer cells under stress conditions. PMID:27325740

  3. Systematic substrate identification indicates a central role for the metalloprotease ADAM10 in axon targeting and synapse function

    PubMed Central

    Kuhn, Peer-Hendrik; Colombo, Alessio Vittorio; Schusser, Benjamin; Dreymueller, Daniela; Wetzel, Sebastian; Schepers, Ute; Herber, Julia; Ludwig, Andreas; Kremmer, Elisabeth; Montag, Dirk; Müller, Ulrike; Schweizer, Michaela; Saftig, Paul; Bräse, Stefan; Lichtenthaler, Stefan F

    2016-01-01

    Metzincin metalloproteases have major roles in intercellular communication by modulating the function of membrane proteins. One of the proteases is the a-disintegrin-and-metalloprotease 10 (ADAM10) which acts as alpha-secretase of the Alzheimer's disease amyloid precursor protein. ADAM10 is also required for neuronal network functions in murine brain, but neuronal ADAM10 substrates are only partly known. With a proteomic analysis of Adam10-deficient neurons we identified 91, mostly novel ADAM10 substrate candidates, making ADAM10 a major protease for membrane proteins in the nervous system. Several novel substrates, including the neuronal cell adhesion protein NrCAM, are involved in brain development. Indeed, we detected mistargeted axons in the olfactory bulb of conditional ADAM10-/- mice, which correlate with reduced cleavage of NrCAM, NCAM and other ADAM10 substrates. In summary, the novel ADAM10 substrates provide a molecular basis for neuronal network dysfunctions in conditional ADAM10-/- mice and demonstrate a fundamental function of ADAM10 in the brain. DOI: http://dx.doi.org/10.7554/eLife.12748.001 PMID:26802628

  4. Control of ADAM17 activity by regulation of its cellular localisation

    PubMed Central

    Lorenzen, Inken; Lokau, Juliane; Korpys, Yvonne; Oldefest, Mirja; Flynn, Charlotte M.; Künzel, Ulrike; Garbers, Christoph; Freeman, Matthew; Grötzinger, Joachim; Düsterhöft, Stefan

    2016-01-01

    An important, irreversible step in many signalling pathways is the shedding of membrane-anchored proteins. A Disintegrin And Metalloproteinase (ADAM) 17 is one of the major sheddases involved in a variety of physiological and pathophysiological processes including regeneration, differentiation, and cancer progression. This central role in signalling implies that ADAM17 activity has to be tightly regulated, including at the level of localisation. Most mature ADAM17 is localised intracellularly, with only a small amount at the cell surface. We found that ADAM17 is constitutively internalised by clathrin-coated pits and that physiological stimulators such as GPCR ligands induce ADAM17-mediated shedding, but do not alter the cell-surface abundance of the protease. In contrast, the PKC-activating phorbol ester PMA, often used as a strong inducer of ADAM17, causes not only proteolysis by ADAM17 but also a rapid increase of the mature protease at the cell surface. This is followed by internalisation and subsequent degradation of the protease. Eventually, this leads to a substantial downregulation of mature ADAM17. Our results therefore imply that physiological activation of ADAM17 does not rely on its relocalisation, but that PMA-induced PKC activity drastically dysregulates the localisation of ADAM17. PMID:27731361

  5. Neuronal ADAM10 Promotes Outgrowth of Small-Caliber Myelinated Axons in the Peripheral Nervous System.

    PubMed

    Meyer zu Horste, Gerd; Derksen, Angelika; Stassart, Ruth; Szepanowski, Fabian; Thanos, Melissa; Stettner, Mark; Boettcher, Christina; Lehmann, Helmar C; Hartung, Hans-Peter; Kieseier, Bernd C

    2015-11-01

    The regulation of myelination and axonal outgrowth in the peripheral nervous system is controlled by a complex signaling network involving various signaling pathways. Members of the A Disintegrin And Metalloproteinase (ADAM) family are membrane-anchored proteinases with both proteolytic and disintegrin characteristics that modulate the function of signaling molecules. One family member, ADAM17, is known to influence myelination by cleaving and thus regulating one of the key signals, neuregulin-1, which controls peripheral nervous system myelination. A similar function for ADAM10 had been suggested by previous in vitro studies. Here, we assessed whether ADAM10 exerts a similar function in vivo and deleted ADAM10 in a cell type-specific manner in either neurons or Schwann cells. We found that ADAM10 is not required in either Schwann cells or neurons for normal myelination during development or for remyelination after injury. Instead, ADAM10 is required specifically in neurons for the outgrowth of myelinated small-fiber axons in vitro and after injury in vivo. Thus, we report for the first time a neuron-intrinsic function of ADAM10 in axonal regeneration that is distinct from that of the related protein family member ADAM17 and that may have implications for targeting ADAM function in nervous system diseases.

  6. John Adams - an outstanding career.

    PubMed

    Lewin, David

    2016-12-07

    A distinguished nurse, teacher, researcher and historian, John Adams was educated at Aylesbury Grammar School and graduated from Selwyn College, Cambridge, with a degree in theological and religious studies.

  7. The DNA-mimic antirestriction proteins ArdA ColIB-P9, Arn T4, and Ocr T7 as activators of H-NS-dependent gene transcription.

    PubMed

    Melkina, Olga E; Goryanin, Ignatiy I; Zavilgelsky, Gennadii B

    2016-11-01

    The antirestriction proteins ArdA ColIb-P9, Arn T4 and Ocr T7 specifically inhibit type I and type IV restriction enzymes and belong to the family of DNA-mimic proteins because their three-dimensional structure is similar to the double-helical B-form DNA. It is proposed that the DNA-mimic proteins are able to bind nucleoid protein H-NS and alleviate H-NS-silencing of the transcription of bacterial genes. Escherichia coli lux biosensors were constructed by inserting H-NS-dependent promoters into a vector, thereby placing each fragment upstream of the promoterless Photorhabdus luminescens luxCDABE operon. It was demonstrated that the DNA-mimic proteins ArdA, Arn and Ocr activate the transcription of H-NS-dependent promoters of the lux operon of marine luminescent bacteria (mesophilic Aliivibrio fischeri and psychrophilic Aliivibrio logei), and the dps gene from E. coli. It was also demonstrated that the ArdA antirestriction protein, the genes of which are located on transmissive plasmids ColIb-P9, R64, PK101, decreases levels of H-NS silencing of the PluxC promoter during conjugation in the recipient bacteria.

  8. N-Glycosylation Regulates ADAM8 Processing and Activation*

    PubMed Central

    Srinivasan, Srimathi; Romagnoli, Mathilde; Bohm, Andrew; Sonenshein, Gail E.

    2014-01-01

    The transmembrane ADAM8 (A Disintegrin And Metalloproteinase 8) protein is abundantly expressed in human breast tumors and derived metastases compared with normal breast tissue, and plays critical roles in aggressive Triple-Negative breast cancers (TNBCs). During ADAM8 maturation, the inactive proform dimerizes or multimerizes and autocatalytically removes the prodomain leading to the formation of the active, processed form. ADAM8 is a glycoprotein; however, little was known about the structure or functional role of these sugar moieties. Here, we report that in estrogen receptor (ER)α-negative, but not -positive, breast cancer cells ADAM8 contains N-glycosylation, which is required for its correct processing and activation. Consistently ADAM8 dimers were detected on the surface of ERα-negative breast cancer cells but not on ERα-positive ones. Site-directed mutagenesis confirmed four N-glycosylazhytion sites (Asn-67, Asn-91, Asn-436, and Asn-612) in human ADAM8. The Asn-67 and Asn-91 prodomain sites contained high mannose, whereas complex type N-glycosylation was observed on Asn-436 and Asn-612 in the active and remnant forms. The Asn-91 and Asn-612 sites were essential for its correct processing and cell surface localization, in particular its exit from the Golgi and endoplasmic reticulum, respectively. The N436Q mutation led to decreased ADAM8 stability due to enhanced lysosomal degradation. In contrast, mutation of the Asn-67 site had only modest effects on enzyme stability and processing. Thus, N-glycosylation is essential for processing, localization, stability, and activity of ADAM8. PMID:25336660

  9. Evolution of Vertebrate Adam Genes; Duplication of Testicular Adams from Ancient Adam9/9-like Loci

    PubMed Central

    Wei, Shuo

    2015-01-01

    Members of the disintegrin metalloproteinase (ADAM) family have important functions in regulating cell-cell and cell-matrix interactions as well as cell signaling. There are two major types of ADAMs: the somatic ADAMs (sADAMs) that have a significant presence in somatic tissues, and the testicular ADAMs (tADAMs) that are expressed predominantly in the testis. Genes encoding tADAMs can be further divided into two groups: group I (intronless) and group II (intron-containing). To date, tAdams have only been reported in placental mammals, and their evolutionary origin and relationship to sAdams remain largely unknown. Using phylogenetic and syntenic tools, we analyzed the Adam genes in various vertebrates ranging from fishes to placental mammals. Our analyses reveal duplication and loss of some sAdams in certain vertebrate species. In particular, there exists an Adam9-like gene in non-mammalian vertebrates but not mammals. We also identified putative group I and group II tAdams in all amniote species that have been examined. These tAdam homologues are more closely related to Adams 9 and 9-like than to other sAdams. In all amniote species examined, group II tAdams lie in close vicinity to Adam9 and hence likely arose from tandem duplication, whereas group I tAdams likely originated through retroposition because of their lack of introns. Clusters of multiple group I tAdams are also common, suggesting tandem duplication after retroposition. Therefore, Adam9/9-like and some of the derived tAdam loci are likely preferred targets for tandem duplication and/or retroposition. Consistent with this hypothesis, we identified a young retroposed gene that duplicated recently from Adam9 in the opossum. As a result of gene duplication, some tAdams were pseudogenized in certain species, whereas others acquired new expression patterns and functions. The rapid duplication of Adam genes has a major contribution to the diversity of ADAMs in various vertebrate species. PMID:26308360

  10. Evolution of Vertebrate Adam Genes; Duplication of Testicular Adams from Ancient Adam9/9-like Loci.

    PubMed

    Bahudhanapati, Harinath; Bhattacharya, Shashwati; Wei, Shuo

    2015-01-01

    Members of the disintegrin metalloproteinase (ADAM) family have important functions in regulating cell-cell and cell-matrix interactions as well as cell signaling. There are two major types of ADAMs: the somatic ADAMs (sADAMs) that have a significant presence in somatic tissues, and the testicular ADAMs (tADAMs) that are expressed predominantly in the testis. Genes encoding tADAMs can be further divided into two groups: group I (intronless) and group II (intron-containing). To date, tAdams have only been reported in placental mammals, and their evolutionary origin and relationship to sAdams remain largely unknown. Using phylogenetic and syntenic tools, we analyzed the Adam genes in various vertebrates ranging from fishes to placental mammals. Our analyses reveal duplication and loss of some sAdams in certain vertebrate species. In particular, there exists an Adam9-like gene in non-mammalian vertebrates but not mammals. We also identified putative group I and group II tAdams in all amniote species that have been examined. These tAdam homologues are more closely related to Adams 9 and 9-like than to other sAdams. In all amniote species examined, group II tAdams lie in close vicinity to Adam9 and hence likely arose from tandem duplication, whereas group I tAdams likely originated through retroposition because of their lack of introns. Clusters of multiple group I tAdams are also common, suggesting tandem duplication after retroposition. Therefore, Adam9/9-like and some of the derived tAdam loci are likely preferred targets for tandem duplication and/or retroposition. Consistent with this hypothesis, we identified a young retroposed gene that duplicated recently from Adam9 in the opossum. As a result of gene duplication, some tAdams were pseudogenized in certain species, whereas others acquired new expression patterns and functions. The rapid duplication of Adam genes has a major contribution to the diversity of ADAMs in various vertebrate species.

  11. iRhoms 1 and 2 are essential upstream regulators of ADAM17-dependent EGFR signaling

    PubMed Central

    Li, Xue; Maretzky, Thorsten; Weskamp, Gisela; Monette, Sébastien; Qing, Xiaoping; Issuree, Priya Darshinee A.; Crawford, Howard C.; McIlwain, David R.; Mak, Tak W.; Salmon, Jane E.; Blobel, Carl P.

    2015-01-01

    The metalloproteinase ADAM17 (a disintegrin and metalloprotease 17) controls EGF receptor (EGFR) signaling by liberating EGFR ligands from their membrane anchor. Consequently, a patient lacking ADAM17 has skin and intestinal barrier defects that are likely caused by lack of EGFR signaling, and Adam17−/− mice die perinatally with open eyes, like Egfr−/− mice. A hallmark feature of ADAM17-dependent EGFR ligand shedding is that it can be rapidly and posttranslationally activated in a manner that requires its transmembrane domain but not its cytoplasmic domain. This suggests that ADAM17 is regulated by other integral membrane proteins, although much remains to be learned about the underlying mechanism. Recently, inactive Rhomboid 2 (iRhom2), which has seven transmembrane domains, emerged as a molecule that controls the maturation and function of ADAM17 in myeloid cells. However, iRhom2−/− mice appear normal, raising questions about how ADAM17 is regulated in other tissues. Here we report that iRhom1/2−/− double knockout mice resemble Adam17−/− and Egfr−/− mice in that they die perinatally with open eyes, misshapen heart valves, and growth plate defects. Mechanistically, we show lack of mature ADAM17 and strongly reduced EGFR phosphorylation in iRhom1/2−/− tissues. Finally, we demonstrate that iRhom1 is not essential for mouse development but regulates ADAM17 maturation in the brain, except in microglia, where ADAM17 is controlled by iRhom2. These results provide genetic, cell biological, and biochemical evidence that a principal function of iRhoms1/2 during mouse development is to regulate ADAM17-dependent EGFR signaling, suggesting that iRhoms1/2 could emerge as novel targets for treatment of ADAM17/EGFR-dependent pathologies. PMID:25918388

  12. Modulation of integrin α4β1 by ADAM28 promotes lymphocyte adhesion and transendothelial migration.

    PubMed

    McGinn, Owen J; English, William R; Roberts, Stephanie; Ager, Ann; Newham, Peter; Murphy, Gillian

    2011-10-01

    ADAMs (a disintegrin and metalloproteinase) are a family of type I transmembrane glycoproteins related to snake venom metalloproteases and disintegrins. They are regulatory proteins that modulate intercellular adhesion and the bioavailability of growth factors, and have been implicated in many disease states, including cancer, immunity and inflammation. One member of the ADAM family, ADAM28, has been reported to bind to the integrin α4β1 in humans; however, the distribution of ADAM28 and the biological consequences of ADAM28-α4β1 interactions are yet to be fully elucidated. The expression of ADAM28 in human and murine tissues was examined by multiple Affymetrix microarray analyses, real-time RT-PCR (reverse transcription-PCR) and immunohistochemical staining. We found that ADAM28 has a relatively restricted expression pattern in mouse and human and is highly expressed in the B-lymphocyte lineage, including chronic lymphocytic leukaemic B-cells. The murine B-lymphoma line L1-2 and recombinant soluble murine ADAM28 were used to investigate ADAM28-α4β1 interactions. Our data reveal that ADAM28 binding to α4β1 is typical of integrin-ligand interactions, since it is attenuated by anti-functional integrin antibodies, and is enhanced by Mn2+ and the integrin mAb (monoclonal antibody) 9EG7. However, a key finding was that soluble ADAM28 unexpectedly enhanced α4β1-dependent cell adhesion to VCAM-1 (vascular cell adhesion molecule-1). In so doing ADAM28 was able to influence lymphocyte adhesion to, and migration through, endothelial monolayers, suggesting a physiological role for ADAM28 in regulating the specific spatial and temporal transendothelial migration of lymphocytes.

  13. Adam Smith on population.

    PubMed

    Spengler, J J

    1970-11-01

    Abstract Adam Smith dealt with questions of population mainly in his Wealth of Nations. His discussion falls roughly under five heads and reflects in considerable measure his image of the English economy. (1) A country's population capacity, given the average level of consumption, was conditioned by the stock of land, the skill with which it was cultivated, and the degree to which division of labour could be increased and thereby augment output for domestic use and sale in external markets. (2) Growth of population was essentially in response to growth of the demand for labour and served to increase division of labour. (3) The social mechanisms underlying elevation of the scale of living are touched upon, and in an optimistic spirit. (4) The distribution of a country's population responded to its progress in opulence, with the rate of this progress conditioned by the degree to which inappropriate (e.g. mercantilist) policies were avoided. (5) Smith dealt briefly with such matters as colonies, education, size of economy, environmental influences, and public policy, all of which he recognized as significant for the quantity and quality of a country's numbers.

  14. Adam Smith and dependency.

    PubMed

    Ozler, Sule

    2012-06-01

    The focus of this paper is the works and life of Adam Smith, who is widely recognized as the father and founder of contemporary economics. Latent content analysis is applied to his seminal text in economics, An Inquiry into the Nature and Causes of the Wealth of Nations (1776). The results reveal that Smith considers dependence on others a problem and sees the solution to this problem in impersonalized interdependence. In addition, his views on social dependency and personal dependency, reflected in his Lectures on Jurisprudence (1963) and The Theory of Moral Sentiments (1759), are analyzed. This analysis suggests a central tension between dependence and independence in Smith's writings. The personal dependency patterns he exhibited in his life, which also suggest a tension between dependence and independence, are identified through a reading of his biographies. Based on insights from psychoanalytic literature, this paper proposes that developing the ideas in the Wealth of Nations was part of Smith's creative solution to this tension. In particular, his solution to one individual's dependence on another was through a system of impersonalized interdependence. In other words, Smith defended against his personal dependence through his economic theorizing.

  15. Thiazolidinediones mimic glucose starvation in facilitating Sp1 degradation through the up-regulation of beta-transducin repeat-containing protein.

    PubMed

    Wei, Shuo; Chuang, Hsiao-Ching; Tsai, Wan-Chi; Yang, Hsiao-Ching; Ho, Shiuh-Rong; Paterson, Andrew J; Kulp, Samuel K; Chen, Ching-Shih

    2009-07-01

    This study investigated the mechanism by which the transcription factor Sp1 is degraded in prostate cancer cells. We recently developed a thiazolidinedione derivative, (Z)-5-(4-hydroxy-3-trifluoromethylbenzylidene)-3-(1-methylcyclohexyl)-thiazolidine-2,4-dione (OSU-CG12), that induces Sp1 degradation in a manner paralleling that of glucose starvation. Based on our finding that thiazolidinediones suppress beta-catenin and cyclin D1 by up-regulating the E3 ligase SCF(beta-TrCP), we hypothesized that beta-transducin repeat-containing protein (beta-TrCP) targets Sp1 for proteasomal degradation in response to glucose starvation or OSU-CG12. Here we show that either treatment of LNCaP cells increased specific binding of Sp1 with beta-TrCP. This direct binding was confirmed by in vitro pull-down analysis with bacterially expressed beta-TrCP. Although ectopic expression of beta-TrCP enhanced the ability of OSU-CG12 to facilitate Sp1 degradation, suppression of endogenous beta-TrCP function by a dominant-negative mutant or small interfering RNA-mediated knockdown blocked OSU-CG12-facilitated Sp1 ubiquitination and/or degradation. Sp1 contains a C-terminal conventional DSG destruction box ((727)DSGAGS(732)) that mediates beta-TrCP recognition and encompasses a glycogen synthase kinase 3beta (GSK3beta) phosphorylation motif (SXXXS). Pharmacological and molecular genetic approaches and mutational analyses indicate that extracellular signal-regulated kinase-mediated phosphorylation of Thr739 and GSK3beta-mediated phosphorylation of Ser728 and Ser732 were critical for Sp1 degradation. The ability of OSU-CG12 to mimic glucose starvation to activate beta-TrCP-mediated Sp1 degradation has translational potential to foster novel strategies for cancer therapy.

  16. The membrane protein PrsS mimics σS in protecting Staphylococcus aureus against cell wall-targeting antibiotics and DNA-damaging agents.

    PubMed

    Krute, Christina N; Bell-Temin, Harris; Miller, Halie K; Rivera, Frances E; Weiss, Andy; Stevens, Stanley M; Shaw, Lindsey N

    2015-05-01

    Staphylococcus aureus possesses a lone extracytoplasmic function (ECF) sigma factor, σ(S). In Bacillus subtilis, the ECF sigma factor, σ(W), is activated through a proteolytic cascade that begins with cleavage of the RsiW anti-sigma factor by a site-1 protease (S1P), PrsW. We have identified a PrsW homologue in S. aureus (termed PrsS) and explored its role in σ(S) regulation. Herein, we demonstrate that although a cognate σ(S) anti-sigma factor currently remains elusive, prsS phenocopies sigS in a wealth of regards. Specifically, prsS expression mimics the upregulation observed for sigS in response to DNA-damaging agents, cell wall-targeting antibiotics and during ex vivo growth in human serum and murine macrophages. prsS mutants also display the same sensitivities of sigS mutants to the DNA-damaging agents methyl methane sulfonate (MMS) and hydrogen peroxide, and the cell wall-targeting antibiotics ampicillin, bacitracin and penicillin-G. These phenotypes appear to be explained by alterations in abundance of proteins involved in drug resistance (Pbp2a, FemB, HmrA) and the response to DNA damage (BmrA, Hpt, Tag). Our findings seem to be mediated by putative proteolytic activity of PrsS, as site-directed mutagenesis of predicted catalytic residues fails to rescue the sensitivity of the mutant to H2O2 and MMS. Finally, a role for PrsS in S. aureus virulence was identified using human and murine models of infection. Collectively, our data indicate that PrsS and σ(S) function in a similar manner, and perhaps mediate virulence and resistance to DNA damage and cell wall-targeting antibiotics, via a common pathway.

  17. ADAM10 Is Involved in Cell Junction Assembly in Early Porcine Embryo Development

    PubMed Central

    Kwon, Jeongwoo; Jeong, Sung-min; Choi, Inchul; Kim, Nam-Hyung

    2016-01-01

    ADAM10 (A Disintegrin and Metalloprotease domain-containing protein 10) is a cell surface protein with a unique structure possessing both potential adhesion and protease domains. However, the role of ADAM10 in preimplantation stage embryos is not clear. In this study, we examined the expression patterns and functional roles of ADAM10 in porcine parthenotes during preimplantation development. The transcription level of ADAM10 dramatically increased from the morula stage onward. Immunostaining revealed that ADAM10 was present in both the nucleus and cytoplasm in early cleavage stage embryos, and localized to the apical region of the outer cells in morula and blastocyst embryos. Knockdown (KD) of ADAM10 using double strand RNA did not alter preimplantation embryo development until morula stage, but resulted in significantly reduced development to blastocyst stage. Moreover, the KD blastocyst showed a decrease in gene expression of adherens and tight junction (AJ/TJ), and an increase in trophectoderm TJ permeability by disrupting TJ assembly. Treatment with an ADAM10 specific chemical inhibitor, GI254023X, at the morula stage also inhibited blastocyst development and led to disruption of TJ assembly. An in situ proximity ligation assay demonstrated direct interaction of ADAM10 with coxsackie virus and adenovirus receptor (CXADR), supporting the involvement of ADAM10 in TJ assembly. In conclusion, our findings strongly suggest that ADADM10 is important for blastocyst formation rather than compaction, particularly for TJ assembly and stabilization in preimplantation porcine parthenogenetic development. PMID:27043020

  18. ADAM10 Is Involved in Cell Junction Assembly in Early Porcine Embryo Development.

    PubMed

    Kwon, Jeongwoo; Jeong, Sung-min; Choi, Inchul; Kim, Nam-Hyung

    2016-01-01

    ADAM10 (A Disintegrin and Metalloprotease domain-containing protein 10) is a cell surface protein with a unique structure possessing both potential adhesion and protease domains. However, the role of ADAM10 in preimplantation stage embryos is not clear. In this study, we examined the expression patterns and functional roles of ADAM10 in porcine parthenotes during preimplantation development. The transcription level of ADAM10 dramatically increased from the morula stage onward. Immunostaining revealed that ADAM10 was present in both the nucleus and cytoplasm in early cleavage stage embryos, and localized to the apical region of the outer cells in morula and blastocyst embryos. Knockdown (KD) of ADAM10 using double strand RNA did not alter preimplantation embryo development until morula stage, but resulted in significantly reduced development to blastocyst stage. Moreover, the KD blastocyst showed a decrease in gene expression of adherens and tight junction (AJ/TJ), and an increase in trophectoderm TJ permeability by disrupting TJ assembly. Treatment with an ADAM10 specific chemical inhibitor, GI254023X, at the morula stage also inhibited blastocyst development and led to disruption of TJ assembly. An in situ proximity ligation assay demonstrated direct interaction of ADAM10 with coxsackie virus and adenovirus receptor (CXADR), supporting the involvement of ADAM10 in TJ assembly. In conclusion, our findings strongly suggest that ADADM10 is important for blastocyst formation rather than compaction, particularly for TJ assembly and stabilization in preimplantation porcine parthenogenetic development.

  19. Secretion-Positive LGI1 Mutations Linked to Lateral Temporal Epilepsy Impair Binding to ADAM22 and ADAM23 Receptors

    PubMed Central

    Dazzo, Emanuela; Belluzzi, Elisa; Malacrida, Sandro; Vitiello, Libero; Greggio, Elisa; Tosatto, Silvio C. E.

    2016-01-01

    Autosomal dominant lateral temporal epilepsy (ADTLE) is a focal epilepsy syndrome caused by mutations in the LGI1 gene, which encodes a secreted protein. Most ADLTE-causing mutations inhibit LGI1 protein secretion, and only a few secretion-positive missense mutations have been reported. Here we describe the effects of four disease-causing nonsynonymous LGI1 mutations, T380A, R407C, S473L, and R474Q, on protein secretion and extracellular interactions. Expression of LGI1 mutant proteins in cultured cells shows that these mutations do not inhibit protein secretion. This finding likely results from the lack of effects of these mutations on LGI1 protein folding, as suggested by 3D protein modelling. In addition, immunofluorescence and co-immunoprecipitation experiments reveal that all four mutations significantly impair interaction of LGI1 with the ADAM22 and ADAM23 receptors on the cell surface. These results support the existence of a second mechanism, alternative to inhibition of protein secretion, by which ADLTE-causing LGI1 mutations exert their loss-of-function effect extracellularly, and suggest that interactions of LGI1 with both ADAM22 and ADAM23 play an important role in the molecular mechanisms leading to ADLTE. PMID:27760137

  20. CJD mimics and chameleons.

    PubMed

    Mead, Simon; Rudge, Peter

    2017-04-01

    Rapidly progressive dementia mimicking Creutzfeldt-Jakob disease (CJD) is a relatively rare presentation but a rewarding one to become familiar with, as the potential diagnoses range from the universally fatal to the completely reversible. Patients require urgent decisions about assessment and investigation and have quickly evolving needs for treatments and support, through symptom management and end-of-life care in most cases. We have based this pragmatic review on the experiences of a specialist prion referral centre in the UK, which, unsurprisingly, is strongly biased towards seeing patients with CJD. Cases eventually proven not to have prion disease might be described as 'CJD-mimics'; being referred from UK neurologists, these are the most challenging cases. CJD in its classical presentation is very rarely mimicked; however, it is highly heterogeneous, and atypical forms can mimic virtually all common neurodegenerative syndromes. Warning features of a mimic include generalised seizures, hyponatraemia, fever, a facial movement disorder, a normal neurological examination and a modestly rapid presentation. Contrast-enhancing lesions or MRI signal hyperintensity outside the striatum, thalamus or cortex and a cerebrospinal fluid pleocytosis are key investigation pointers to a CJD mimic.

  1. Metalloproteinases ADAM12 and MMP-14 are associated with cavernous sinus invasion in pituitary adenomas.

    PubMed

    Wang, Junwen; Voellger, Benjamin; Benzel, Julia; Schlomann, Uwe; Nimsky, Christopher; Bartsch, Jörg W; Carl, Barbara

    2016-09-15

    Invasion of tumor cells critically depends on cell-cell or cell-extracellular matrix interactions. Enzymes capable of modulating these interactions belong to the proteinase families of ADAM (a disintegrin and metalloprotease) and MMP (matrix metalloprotease) proteins. Our objective is to examine their expression levels and evaluate the relationship between expression levels and cavernous sinus invasion in pituitary adenomas. Tissue samples from 35 patients with pituitary adenomas were analyzed. Quantitative real-time polymerase chain reaction (qPCR) was employed to assess mRNA expression levels for ADAM and MMP genes. Protein levels were examined using immunohistochemistry and Western Blot. Correlation analyses between expression levels and clinical parameters were performed. By silencing ADAM12 and MMP-14 with siRNA in a mouse pituitary adenoma cell line (TtT/GF), their cellular effects were investigated. In our study, nine women and 26 men were included, with a mean age of 53.1 years (range 15-84 years) at the time of surgery. There were 19 cases with cavernous sinus invasion. The proteins ADAM12 and MMP-14 were significantly up-regulated in invasive adenomas compared to noninvasive adenomas. Both human isoforms of ADAM12 (ADAM12L and ADAM12s) were involved in tumor invasion; moreover, ADAM12L was found to correlate positively with Ki-67 proliferation index in pituitary adenomas. In TtT/GF pituitary adenoma cells, silencing of ADAM12 and MMP-14 significantly inhibited cell invasion and migration, respectively, whereas only silencing of ADAM12 suppressed cell proliferation. We conclude that ADAM12 and MMP-14 are associated with cavernous sinus invasion in pituitary adenomas, which qualifies these proteins in diagnosis and therapy.

  2. The Cytosolic Domain of Protein-tyrosine Kinase 7 (PTK7), Generated from Sequential Cleavage by a Disintegrin and Metalloprotease 17 (ADAM17) and γ-Secretase, Enhances Cell Proliferation and Migration in Colon Cancer Cells*

    PubMed Central

    Na, Hye-Won; Shin, Won-Sik; Ludwig, Andreas; Lee, Seung-Taek

    2012-01-01

    Protein-tyrosine kinase 7 (PTK7) is a member of the defective receptor protein-tyrosine kinases and is known to function as a regulator of planar cell polarity during development. Its expression is up-regulated in some cancers including colon carcinomas. A 100-kDa fragment of PTK7 was detected in the culture media from colon cancer cells and HEK293 cells. The shed fragment was named sPTK7-Ig1–7 because its molecular mass was very similar to that of the entire extracellular domain of PTK7 that contains immunoglobulin-like loops 1 to 7 (Ig1–7). The shedding of sPTK7-Ig1–7 was enhanced by treatment with phorbol 12-myristate 13-acetate. In addition to the sPTK7-Ig1–7 found in the culture medium, two C-terminal fragments of PTK7 were detected in the cell lysates: PTK7-CTF1, which includes a transmembrane segment and a cytoplasmic domain, and PTK7-CTF2, which lacks most of the transmembrane segment from PTK7-CTF1. Analysis of PTK7 processing in the presence of various protease inhibitors or after knockdown of potential proteases suggests that shedding of PTK7 into sPTK7-Ig1–7 and PTK7-CTF1 is catalyzed by ADAM17, and further cleavage of PTK7-CTF1 into PTK7-CTF2 is mediated by the γ-secretase complex. PTK7-CTF2 localizes to the nucleus and enhances proliferation, migration, and anchorage-independent colony formation. Our findings demonstrate a novel role for PTK7 in the tumorigenesis via generation of PTK7-CTF2 by sequential cleavage of ADAM17 and γ-secretase. PMID:22665490

  3. ADAM8 is a negative regulator of retinal neovascularization and of the growth of heterotopically injected tumor cells in mice

    PubMed Central

    Guaiquil, Victor H.; Swendeman, Steven; Zhou, Wenhui; Guaiquil, Patricio; Weskamp, Gisela; Bartsch, Jörg W.

    2010-01-01

    ADAM8 is a member of the “a disintegrin and metalloproteinase” (ADAM) family of membrane-anchored metalloproteinases. ADAM8-deficient mice have no evident spontaneous developmental or pathological defects, and little is currently known about the role of ADAM8 in disease. Here, we investigated the contribution of ADAM8 to pathological neovascularization in mice using an oxygen-induced retinopathy (OIR) model and heterotopical injection of tumor cells. We found an increase in retinal re-vascularization but fewer neovascular tufts in the OIR model and increased growth of heterotopically injected tumor cells in Adam8−/− mice compared with wild-type controls. These results suggest that ADAM8 functions to limit both of these processes in wild-type mice. In cell-based assays, overexpression of ADAM8 increased the ectodomain shedding of several co-expressed membrane proteins with roles in angiogenesis (CD31, Tie-2, Flk-1, Flt-1, EphrinB2, EphB4, VE-cadherin, KL-1, E-selectin, and neuregulin-1β2). Thus, dysregulated expression of ADAM8 in endothelial cells in vivo could potentially increase the processing of these and other substrate proteins. Taken together, our findings suggest that inhibiting ADAM8 could be useful for promoting re-vascularization and thereby preventing formation of neovascular tufts in proliferative retinopathies. On the other hand, blocking ADAM8 could be detrimental in the context of rapidly growing tumors. PMID:20119708

  4. ADAM12 induces estrogen-independence in breast cancer cells.

    PubMed

    Roy, Roopali; Moses, Marsha A

    2012-02-01

    Antiestrogen therapy has been used successfully to prolong disease-free and overall survival of ER positive breast cancer patients. However, 50% of patients with ER+ tumors fail to respond to such therapy or eventually acquire resistance to endocrine therapy, resulting in tumor progression and mortality. It is imperative, therefore, to understand the mechanisms that lead to hormone refractory breast cancer in order to develop therapeutics that can modulate the resistance to antiestrogen therapy. The protease, ADAM12, can be detected in the urine of breast cancer patients and its levels correlate with disease status, stage, and cancer risk. Within the context of this study, the authors have investigated the role of the two distinct isoforms of ADAM12 in breast tumor cell proliferation and as potential mediators of endocrine resistance. Using stable clones of ADAM12-overexpressing MCF-7 cells, the authors analyzed proliferation rates of these ER+ breast tumor cells both in estrogen-depleted medium and in the presence of the antiestrogens, tamoxifen, and ICI 182,780. Acquired estrogen resistance in these cells was analyzed using phospho-RTK analysis. Upregulation and phosphorylation of proteins were detected via immunoprecipitation and immunoblotting. EGFR and MAPK inhibitors were used to explore the mechanism of acquired estrogen resistance in breast tumor cells. It was observed that overexpression of the two isoforms, transmembrane ADAM12-L, and secreted ADAM12-S, in breast tumor cells promoted estrogen-independent proliferation. In ADAM12-L-expressing cells, estrogen-independence was a direct result of increased EGFR expression and MAPK activation, whereas, the mechanism in ADAM12-S-expressing cells may be enhanced IGF-1R signaling. The importance of the EGFR signaling pathway in the estrogen-independent growth of ADAM12-L expressing cells was highlighted by the effect of EGFR inhibitors AG1478 and PD15035 or MAPK inhibitor U0126, each of which abolished the

  5. Host proteins that bind to or mimic SV40 large T antigen: using antibodies to look at protein interactions and their significance

    PubMed Central

    Mole, S. E.; Gannon, J. V.; Anton, I. A.; Ford, M. J.; Lane, D. P.

    1989-01-01

    The papovavirus SV40 is able to induce tumours in susceptible hosts and will transform cells in vitro. Its major early protein, large T antigen, is required for viral DNA synthesis, both in vivo and in vitro, and is also responsible for the oncogenic action of the virus. We have made use of an extensive library of anti-T monoclonal antibodies to investigate the cellular effects of T. Large T shares an antigenic determinant with a growth-regulated host protein, p68, which is a member of an expanding super-family of helicases with particular homology to the translation initiation factor elF-4A. We have also studied the binding and interaction of large T with two particular host components: the replicative enzyme DNA polymerase α and the proto-oncogene p53. These two proteins bind to similar regions of T and exert similar effects on its antigenic structure. We found that p53 can block the binding of DNA polymerase α to T as well as co-existing with DNA polymerase α in a trimeric complex with T. This suggests that these interactions may be important in the oncogenic and replicative action of large T.

  6. ADAM12: a potential target for the treatment of chronic wounds.

    PubMed

    Harsha, Asheesh; Stojadinovic, Olivera; Brem, Harold; Sehara-Fujisawa, Atsuko; Wewer, Ulla; Loomis, Cynthia A; Blobel, Carl P; Tomic-Canic, Marjana

    2008-08-01

    Wound healing is a complex process involving multiple cellular events, including cell proliferation, migration, and tissue remodeling. A disintegrin and metalloprotease 12 (ADAM12) is a membrane-anchored metalloprotease, which has been implicated in activation-inactivation of growth factors that play an important role in wound healing, including heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF) and insulin growth factor (IGF) binding proteins. Here, we report that expression of ADAM12 is fivefold upregulated in the nonhealing edge of chronic ulcers compared to healthy skin, based on microarrays of biopsies taken from five patients and from healthy controls (p = 0.013). The increase in ADAM12 expression in chronic ulcers was confirmed by quantitative real-time polymerase chain reaction (RT-PCR). Moreover, immunohistochemical analysis demonstrated a pronounced increase in the membranous and intracellular signal for ADAM12 in the epidermis of chronic wounds compared to healthy skin. These findings, coupled with our previous observations that lack of keratinocyte migration contributes to the pathogenesis of chronic ulcers, prompted us to evaluate how the absence of ADAM12 affects the migration of mouse keratinocytes. Skin explants from newborn ADAM12-/- or wild-type (WT) mice were used to quantify keratinocyte migration out of the explants over a period of 7 days. We found a statistically significant increase in the migration of ADAM12-/- keratinocytes compared to WT control (p = 0.0014) samples. Taken together, the upregulation of ADAM12 in chronic wounds and the increased migration of keratinocytes in the absence of ADAM12 suggest that ADAM12 is an important mediator of wound healing. We hypothesize that increased expression of ADAM12 in chronic wounds impairs wound healing through the inhibition of keratinocyte migration and that topical ADAM12 inhibitors may therefore prove useful for the treatment of chronic wounds.

  7. A Disintegrin and Metalloproteinase-12 (ADAM12): Function, Roles in Disease Progression, and Clinical Implications

    PubMed Central

    Nyren-Erickson, Erin K.; Jones, Justin M.; Srivastava, D. K.

    2013-01-01

    Background A disintegrin and metalloproteinase-12 (ADAM12) is a member of the greater ADAM family of enzymes: these are multifunctional, generally membrane-bound, zinc proteases for which there are forty genes known (21 of these appearing in humans). ADAM12 has been implicated in the pathogenesis of various cancers, liver fibrogenesis, hypertension, and asthma, and its elevation or decrease in human serum has been linked to these and other physiological/pathological conditions. Scope In this review, we begin with a brief overview of the ADAM family of enzymes and protein structure. We then discuss the role of ADAM12 in the progression and/or diagnosis of various disease conditions, and we will conclude with an exploration of currently known natural and synthetic inhibitors. Major Conclusions ADAM12 has potential to emerge as a successful drug target, although targeting the metalloproteinase domain with any specificity will be difficult to achieve due to structural similarity between the members of the ADAM and MMP family of enzymes. Overall, more research is required to establish ADAM12 being as a highly desirable biomarker and drug target of different diseases, and their selective inhibitors as potential therapeutic agents. General Significance Given the appearance of elevated levels of ADAM12 in various diseases, particularly breast cancer, our understanding of this enzyme both as a biomarker and a potential drug target could help make significant inroads into both early diagnosis and treatment of disease. PMID:23680494

  8. Increase of α-Secretase ADAM10 in Platelets Along Cognitively Healthy Aging.

    PubMed

    Schuck, Florian; Wolf, Dominik; Fellgiebel, Andreas; Endres, Kristina

    2016-01-01

    ADAM10 is one of the key players in ectodomain-shedding of the amyloid-β protein precursor (AβPP). Previous research with postmortem tissue has shown reduced expression and activity of ADAM10 within the central nervous system (CNS) of Alzheimer's disease (AD) patients. Determination of cerebral ADAM10 in living humans is hampered by its transmembrane property; only the physiological AβPP cleavage product generated by ADAM10, sAβPPα, can be assessed in cerebrospinal fluid. Establishment of surrogate markers in easily accessible material therefore is crucial. It has been demonstrated that ADAM10 is expressed in platelets and that platelet amount is decreased in AD patients. Just recently it has been shown that platelet ADAM10 and cognitive performance of AD patients positively correlate. In contrast to AD patients, to our knowledge almost no information has been published regarding ADAM10 expression during normal aging. We investigated ADAM10 amount and activity in platelets of cognitively healthy individuals from three different age groups ranging from 22-85 years. Interestingly, we observed an age-dependent increase in ADAM10 levels and activity in platelets.

  9. ADAM12-deficient zebrafish exhibit retardation in body growth at the juvenile stage without developmental defects.

    PubMed

    Tokumasu, Yudai; Iida, Atsuo; Wang, Zi; Ansai, Satoshi; Kinoshita, Masato; Sehara-Fujisawa, Atsuko

    2016-05-01

    ADAM (a disintegrin and metalloprotease) constitutes a family of multi-domain proteins that are involved in development, homeostasis, and disease. ADAM12 plays important roles in myogenesis and adipogenesis in mice; however, the precise physiological mechanisms are not known, and the function of this gene in other vertebrates has not been examined. In this study, we used a simple model vertebrate, the zebrafish, to investigate the functions of ADAM12 during development. Zebrafish adam12 is conserved with those of mammals in the synteny and the amino-acid sequence. We examined adam12 expression in zebrafish embryos by whole mount in situ hybridization and the promoter activity of the adam12 upstream sequence. We found that adam12 is strongly expressed in the cardiovascular system, erythroid progenitors, brain, and jaw cartilage during zebrafish development, and adam12-knockout zebrafish exhibited reduced body size in the juvenile stage without apparent morphological defects. Taken together, these results suggest that adam12 plays a significant role in the regulation of body growth during juvenile stage in zebrafish, although the precise molecular mechanisms await further study.

  10. Metalloprotease-disintegrin ADAM12 expression is regulated by Notch signaling via microRNA-29.

    PubMed

    Li, Hui; Solomon, Emilia; Duhachek Muggy, Sara; Sun, Danqiong; Zolkiewska, Anna

    2011-06-17

    Metalloprotease-disintegrin ADAM12 is overexpressed and frequently mutated in breast cancer. We report here that ADAM12 expression in cultured mammalian cells is up-regulated by Notch signals. Expression of a constitutively active form of Notch1 in murine fibroblasts, myoblasts, or mammary epithelial cells or activation of the endogenous Notch signaling by co-culture with ligand-expressing cells increases ADAM12 protein and mRNA levels. Up-regulation of ADAM12 expression by Notch requires new transcription, is activated in a CSL-dependent manner, and is abolished upon inhibition of IκB kinase. Expression of a constitutively active Notch1 in NIH3T3 cells increases the stability of Adam12 mRNA. We further show that the microRNA-29 family, which has a predicted conserved site in the 3'-untranslated region of mouse Adam12, plays a critical role in mediating the stimulatory effect of Notch on ADAM12 expression. In human cells, Notch up-regulates the expression of the long form, but not the short form, of ADAM12 containing a divergent 3'-untranslated mRNA region. These studies uncover a novel paradigm in Notch signaling and establish Adam12 as a Notch-related gene.

  11. Role of MicroRNA-103a Targeting ADAM10 in Abdominal Aortic Aneurysm

    PubMed Central

    Jiao, Tong; Yao, Ye; Zhang, Bo; Sun, Qing-Feng; Li, Jing-Bo; Yuan, Chao; Jing, Bao; Wang, Yun-Peng

    2017-01-01

    MicroRNAs (miRNAs) are deregulated in various vascular ailments including abdominal aortic aneurysm (AAA). MiR-103 is involved in vascular, metabolic, and malignant diseases, but whether it participates in the pathogenesis of AAA remains elusive. ADAM10 plays a vital role in the formation of aneurysm, but whether miRs modulate its activity during AAA formation is totally unknown. In this study, we detected the significantly increased protein expression of ADAM10 in angiotensin II induced murine AAA specimens, while the mRNA expression of ADAM10 was similar between AAA and control, suggesting the posttranscriptional regulation. The ADAM10 specific inhibitor GI254023X dramatically reduced the macrophage infiltration of murine abdominal aorta. Bioinformatic predictions suggest that ADAM10 is the target of miR-103a/107 but the binding site is exclusive. At the cellular level, miR-103a-1 suppressed the protein expression of ADAM10, while antisense miR-103a-1 increased its expression. Particularly, with the progression of murine AAA, the mRNA expression of miR-103a/107 substantially decreased and the protein expression of ADAM10 greatly increased. Together, our data afford the new insight that miR-103a inhibited AAA growth via targeting ADAM10, which might be a promising therapeutic strategy to alleviate AAA. PMID:28357407

  12. Role of MicroRNA-103a Targeting ADAM10 in Abdominal Aortic Aneurysm.

    PubMed

    Jiao, Tong; Yao, Ye; Zhang, Bo; Hao, Da-Cheng; Sun, Qing-Feng; Li, Jing-Bo; Yuan, Chao; Jing, Bao; Wang, Yun-Peng; Wang, Hai-Yang

    2017-01-01

    MicroRNAs (miRNAs) are deregulated in various vascular ailments including abdominal aortic aneurysm (AAA). MiR-103 is involved in vascular, metabolic, and malignant diseases, but whether it participates in the pathogenesis of AAA remains elusive. ADAM10 plays a vital role in the formation of aneurysm, but whether miRs modulate its activity during AAA formation is totally unknown. In this study, we detected the significantly increased protein expression of ADAM10 in angiotensin II induced murine AAA specimens, while the mRNA expression of ADAM10 was similar between AAA and control, suggesting the posttranscriptional regulation. The ADAM10 specific inhibitor GI254023X dramatically reduced the macrophage infiltration of murine abdominal aorta. Bioinformatic predictions suggest that ADAM10 is the target of miR-103a/107 but the binding site is exclusive. At the cellular level, miR-103a-1 suppressed the protein expression of ADAM10, while antisense miR-103a-1 increased its expression. Particularly, with the progression of murine AAA, the mRNA expression of miR-103a/107 substantially decreased and the protein expression of ADAM10 greatly increased. Together, our data afford the new insight that miR-103a inhibited AAA growth via targeting ADAM10, which might be a promising therapeutic strategy to alleviate AAA.

  13. Apparent reduction of ADAM10 in scrapie-infected cultured cells and in the brains of scrapie-infected rodents.

    PubMed

    Chen, Cao; Lv, Yan; Zhang, Bao-Yun; Zhang, Jin; Shi, Qi; Wang, Jing; Tian, Chan; Gao, Chen; Xiao, Kang; Ren, Ke; Zhou, Wei; Dong, Xiao-Ping

    2014-12-01

    It has been described that A disintegrin and metalloproteinase (ADAM10) may involve in the physiopathology of prion diseases, but the direct molecular basis still remains unsolved. In this study, we confirmed that ADAM10 was able to cleave recombinant human prion protein in vitro. Using immunoprecipitation tests (IP) and immunofluorescent assays (IFA), reliable molecular interaction between the native cellular form of PrP (PrP(C)) and ADAM10 was observed not only in various cultured neuronal cell lines but also in brain homogenates of healthy hamsters and mice. Only mature ADAM10 (after removal of its prodomain) molecules showed the binding activity with the native PrP(C). Remarkably more prion protein (PrP)-ADAM10 complexes were detected in the membrane fraction of cultured cells. In the scrapie-infected SMB cell model, the endogenous ADAM10 levels, especially the mature ADAM10, were significantly decreased in the fraction of cell membrane. IP and IFA tests of prion-infected SMB-S15 cells confirmed no detectable PrP-ADAM10 complex in the cellular lysates and PrP-ADAM10 co-localization on the cell surface. Furthermore, we demonstrated that the levels of ADAM10 in the brain homogenates of scrapie agent 263K-infected hamsters and agent ME7-infected mice were also almost diminished at the terminal stage, showing time-dependent decreases during the incubation period. Our data here provide the solid molecular basis for the endoproteolysis of ADAM10 on PrP molecules and interaction between ADAM10 and PrP(C). Obvious loss of ADAM10 during prion infection in vitro and in vivo highlights that ADAM10 may play essential pathophysiological roles in prion replication and accumulation.

  14. The Role of SnoN in Transforming Growth Factor β1-induced Expression of Metalloprotease-Disintegrin ADAM12*

    PubMed Central

    Solomon, Emilia; Li, Hui; Duhachek Muggy, Sara; Syta, Emilia; Zolkiewska, Anna

    2010-01-01

    Increased expression of metalloprotease-disintegrin ADAM12 is a hallmark of several pathological conditions, including cancer, cardiovascular disease, and certain inflammatory diseases of the central nervous system or the muscoskeletal system. We show that transforming growth factor β1 (TGFβ1) is a potent inducer of ADAM12 mRNA and protein in mouse fibroblasts and in mouse and human mammary epithelial cells. Induction of ADAM12 is detected within 2 h of treatment with TGFβ1, is Smad2/Smad3-dependent, and is a result of derepression of the Adam12 gene. SnoN, a negative regulator of the TGFβ signaling pathway, is a master regulator of ADAM12 expression in response to TGFβ1 stimulation. Overexpression of SnoN in NIH3T3 cells reduces the magnitude of ADAM12 induction by TGFβ1 treatment. Down-regulation of SnoN expression by short hairpin RNA enhances TGFβ1-induced expression of ADAM12. In a panel of TGFβ1-responsive cancer cell lines with high expression of SnoN, induction of ADAM12 by TGFβ1 is significantly impaired, suggesting that the endogenous SnoN plays a role in regulating ADAM12 expression in response to TGFβ1. Identification of SnoN as a repressor of the ADAM12 gene should contribute to advances in the studies on the role of ADAM12 in tumor progression and in the development of other pathologies. PMID:20457602

  15. The role of SnoN in transforming growth factor beta1-induced expression of metalloprotease-disintegrin ADAM12.

    PubMed

    Solomon, Emilia; Li, Hui; Duhachek Muggy, Sara; Syta, Emilia; Zolkiewska, Anna

    2010-07-16

    Increased expression of metalloprotease-disintegrin ADAM12 is a hallmark of several pathological conditions, including cancer, cardiovascular disease, and certain inflammatory diseases of the central nervous system or the muscoskeletal system. We show that transforming growth factor beta1 (TGFbeta1) is a potent inducer of ADAM12 mRNA and protein in mouse fibroblasts and in mouse and human mammary epithelial cells. Induction of ADAM12 is detected within 2 h of treatment with TGFbeta1, is Smad2/Smad3-dependent, and is a result of derepression of the Adam12 gene. SnoN, a negative regulator of the TGFbeta signaling pathway, is a master regulator of ADAM12 expression in response to TGFbeta1 stimulation. Overexpression of SnoN in NIH3T3 cells reduces the magnitude of ADAM12 induction by TGFbeta1 treatment. Down-regulation of SnoN expression by short hairpin RNA enhances TGFbeta1-induced expression of ADAM12. In a panel of TGFbeta1-responsive cancer cell lines with high expression of SnoN, induction of ADAM12 by TGFbeta1 is significantly impaired, suggesting that the endogenous SnoN plays a role in regulating ADAM12 expression in response to TGFbeta1. Identification of SnoN as a repressor of the ADAM12 gene should contribute to advances in the studies on the role of ADAM12 in tumor progression and in the development of other pathologies.

  16. Extravillous trophoblast-associated ADAM12 exerts pro-invasive properties, including induction of integrin beta 1-mediated cellular spreading.

    PubMed

    Biadasiewicz, Katarzyna; Fock, Valerie; Dekan, Sabine; Proestling, Katharina; Velicky, Philipp; Haider, Sandra; Knöfler, Martin; Fröhlich, Camilla; Pollheimer, Jürgen

    2014-05-01

    ADAM12, consisting of a membrane-bound (ADAM12L) and a secreted (ADAM12S) form, is expressed exclusively in regenerating and developing tissue as well as in certain cancer types. Strong ADAM12 expression levels have been noticed in the human placenta, and deregulated ADAM12S levels were associated with various pregnancy-related disorders including pre-eclampsia and intrauterine growth restriction. However, the role of ADAM12 in trophoblast motility has not been investigated so far. Hence, the present study aimed to investigate the specific function of the protease by using different primary trophoblast cell models. Immunofluorescence and Western blot analyses of first trimester placental tissue and differentiating primary first trimester cytotrophoblasts (CTBs) indicated strong upregulation of both of the ADAM12 isoforms during extravillous trophoblast differentiation. Functional assays involving short interfering RNA (siRNA)-mediated knockdown studies in primary CTBs and first trimester explant cultures revealed a significant repression of trophoblast motility upon partial loss of ADAM12. Conversely, isoform-specific overexpression in the ADAM12-negative trophoblast cell line SGHPL-5 enhanced the invasive capacity of these cells. We further confirmed proteolytic activity of trophoblast-derived ADAM12S by demonstrating its potential to degrade insulin-like growth factor-binding protein 3. Finally, we suggest that ADAM12S exerts its pro-migratory function in trophoblasts by inducing integrin beta 1-mediated cellular spreading.

  17. Identification of Novel Interaction between ADAM17 (a Disintegrin and Metalloprotease 17) and Thioredoxin-1*

    PubMed Central

    Aragão, Annelize Z. B.; Nogueira, Maria Luiza C.; Granato, Daniela C.; Simabuco, Fernando M.; Honorato, Rodrigo V.; Hoffman, Zaira; Yokoo, Sami; Laurindo, Francisco R. M.; Squina, Fabio M.; Zeri, Ana Carolina M.; Oliveira, Paulo S. L.; Sherman, Nicholas E.; Paes Leme, Adriana F.

    2012-01-01

    ADAM17, which is also known as TNFα-converting enzyme, is the major sheddase for the EGF receptor ligands and is considered to be one of the main proteases responsible for the ectodomain shedding of surface proteins. How a membrane-anchored proteinase with an extracellular catalytic domain can be activated by inside-out regulation is not completely understood. We characterized thioredoxin-1 (Trx-1) as a partner of the ADAM17 cytoplasmic domain that could be involved in the regulation of ADAM17 activity. We induced the overexpression of the ADAM17 cytoplasmic domain in HEK293 cells, and ligands able to bind this domain were identified by MS after protein immunoprecipitation. Trx-1 was also validated as a ligand of the ADAM17 cytoplasmic domain and full-length ADAM17 recombinant proteins by immunoblotting, immunolocalization, and solid phase binding assay. In addition, using nuclear magnetic resonance, it was shown in vitro that the titration of the ADAM17 cytoplasmic domain promotes changes in the conformation of Trx-1. The MS analysis of the cross-linked complexes showed cross-linking between the two proteins by lysine residues. To further evaluate the functional role of Trx-1, we used a heparin-binding EGF shedding cell model and observed that the overexpression of Trx-1 in HEK293 cells could decrease the activity of ADAM17, activated by either phorbol 12-myristate 13-acetate or EGF. This study identifies Trx-1 as a novel interaction partner of the ADAM17 cytoplasmic domain and suggests that Trx-1 is a potential candidate that could be involved in ADAM17 activity regulation. PMID:23105116

  18. Identification of novel interaction between ADAM17 (a disintegrin and metalloprotease 17) and thioredoxin-1.

    PubMed

    Aragão, Annelize Z B; Nogueira, Maria Luiza C; Granato, Daniela C; Simabuco, Fernando M; Honorato, Rodrigo V; Hoffman, Zaira; Yokoo, Sami; Laurindo, Francisco R M; Squina, Fabio M; Zeri, Ana Carolina M; Oliveira, Paulo S L; Sherman, Nicholas E; Paes Leme, Adriana F

    2012-12-14

    ADAM17, which is also known as TNFα-converting enzyme, is the major sheddase for the EGF receptor ligands and is considered to be one of the main proteases responsible for the ectodomain shedding of surface proteins. How a membrane-anchored proteinase with an extracellular catalytic domain can be activated by inside-out regulation is not completely understood. We characterized thioredoxin-1 (Trx-1) as a partner of the ADAM17 cytoplasmic domain that could be involved in the regulation of ADAM17 activity. We induced the overexpression of the ADAM17 cytoplasmic domain in HEK293 cells, and ligands able to bind this domain were identified by MS after protein immunoprecipitation. Trx-1 was also validated as a ligand of the ADAM17 cytoplasmic domain and full-length ADAM17 recombinant proteins by immunoblotting, immunolocalization, and solid phase binding assay. In addition, using nuclear magnetic resonance, it was shown in vitro that the titration of the ADAM17 cytoplasmic domain promotes changes in the conformation of Trx-1. The MS analysis of the cross-linked complexes showed cross-linking between the two proteins by lysine residues. To further evaluate the functional role of Trx-1, we used a heparin-binding EGF shedding cell model and observed that the overexpression of Trx-1 in HEK293 cells could decrease the activity of ADAM17, activated by either phorbol 12-myristate 13-acetate or EGF. This study identifies Trx-1 as a novel interaction partner of the ADAM17 cytoplasmic domain and suggests that Trx-1 is a potential candidate that could be involved in ADAM17 activity regulation.

  19. What's an Adam's Apple? (For Kids)

    MedlinePlus

    ... Happens in the Operating Room? What's an Adam's Apple? KidsHealth > For Kids > What's an Adam's Apple? A A A You're at the high ... the throat. This is what's called an Adam's apple. Everyone's larynx grows during puberty, but a girl's ...

  20. The shedding activity of ADAM17 is sequestered in lipid rafts

    SciTech Connect

    Tellier, Edwige; Canault, Matthias; Rebsomen, Laure; Bonardo, Bernadette; Juhan-Vague, Irene; Nalbone, Gilles; Peiretti, Franck . E-mail: Franck.Peiretti@medecine.univ-mrs.fr

    2006-12-10

    The tumor necrosis factor-alpha (TNF) converting enzyme (ADAM17) is a metalloprotease-disintegrin responsible for the cleavage of several biologically active transmembrane proteins. However, the substrate specificity of ADAM17 and the regulation of its shedding activity are still poorly understood. Here, we report that during its transport through the Golgi apparatus, ADAM17 is included in cholesterol-rich membrane microdomains (lipid rafts) where its prodomain is cleaved by furin. Consequently, ADAM17 shedding activity is sequestered in lipid rafts, which is confirmed by the fact that metalloproteinase inhibition increases the proportion of ADAM17 substrates (TNF and its receptors TNFR1 and TNFR2) in lipid rafts. Membrane cholesterol depletion increases the ADAM17-dependent shedding of these substrates demonstrating the importance of lipid rafts in the control of this process. Furthermore, ADAM17 substrates are present in different proportions in lipid rafts, suggesting that the entry of each of these substrates in these particular membrane microdomains is specifically regulated. Our data support the idea that one of the mechanisms regulating ADAM17 substrate cleavage involves protein partitioning in lipid rafts.

  1. Parasomnias and their mimics.

    PubMed

    Malhotra, Raman K; Avidan, Alon Y

    2012-11-01

    Parasomnias are classified into nonrapid eye movement and rapid eye movement sleep parasomnias. It is important for the clinician to consider other parasomnia mimics that present to the sleep disorders clinic. These conditions can be differentiated by taking a detailed sleep history and conducting nocturnal polysomnograms to evaluate for potential comorbidities and better characterize the disorder. Mainstays of treatment include treating any underlying primary sleep disorders that induce sleep fragmentation and could trigger the parasomnia, as well as implementing safety precautions to protect patients and their household. Pharmacologic treatment of many parasomnias is also available if needed and clinically indicated.

  2. TspanC8 Tetraspanins and A Disintegrin and Metalloprotease 10 (ADAM10) Interact via Their Extracellular Regions

    PubMed Central

    Noy, Peter J.; Yang, Jing; Reyat, Jasmeet S.; Matthews, Alexandra L.; Charlton, Alice E.; Furmston, Joanna; Rogers, David A.; Rainger, G. Ed; Tomlinson, Michael G.

    2016-01-01

    A disintegrin and metalloprotease 10 (ADAM10) is a ubiquitously expressed transmembrane metalloprotease that cleaves the extracellular regions from its transmembrane substrates. ADAM10 is essential for embryonic development and is implicated in cancer, Alzheimer, and inflammatory diseases. The tetraspanins are a superfamily of 33 four-transmembrane proteins in mammals, of which the TspanC8 subgroup (Tspan5, 10, 14, 15, 17, and 33) promote ADAM10 intracellular trafficking and enzymatic maturation. However, the interaction between TspanC8s and ADAM10 has only been demonstrated in overexpression systems and the interaction mechanism remains undefined. To address these issues, an antibody was developed to Tspan14, which was used to show co-immunoprecipitation of Tspan14 with ADAM10 in primary human cells. Chimeric Tspan14 constructs demonstrated that the large extracellular loop of Tspan14 mediated its co-immunoprecipitation with ADAM10, and promoted ADAM10 maturation and trafficking to the cell surface. Chimeric ADAM10 constructs showed that membrane-proximal stalk, cysteine-rich, and disintegrin domains of ADAM10 mediated its co-immunoprecipitation with Tspan14 and other TspanC8s. This TspanC8-interacting region was required for ADAM10 exit from the endoplasmic reticulum. Truncated ADAM10 constructs revealed differential TspanC8 binding requirements for the stalk, cysteine-rich, and disintegrin domains. Moreover, Tspan15was the only TspanC8 to promote cleavage of the ADAM10 substrate N-cadherin, whereas Tspan14 was unique in reducing cleavage of the platelet collagen receptor GPVI. These findings suggest that ADAM10 may adopt distinct conformations in complex with different TspanC8s, which could impact on substrate selectivity. Furthermore, this study identifies regions of TspanC8s and ADAM10 for potential interaction-disrupting therapeutic targeting. PMID:26668317

  3. ADAM8 expression in invasive breast cancer promotes tumor dissemination and metastasis

    PubMed Central

    Romagnoli, Mathilde; Mineva, Nora D; Polmear, Michael; Conrad, Catharina; Srinivasan, Srimathi; Loussouarn, Delphine; Barillé-Nion, Sophie; Georgakoudi, Irene; Dagg, Áine; McDermott, Enda W; Duffy, Michael J; McGowan, Patricia M; Schlomann, Uwe; Parsons, Maddy; Bartsch, Jörg W; Sonenshein, Gail E

    2014-01-01

    The transmembrane metalloprotease-disintegrin ADAM8 mediates cell adhesion and shedding of ligands, receptors and extracellular matrix components. Here, we report that ADAM8 is abundantly expressed in breast tumors and derived metastases compared to normal tissue, especially in triple-negative breast cancers (TNBCs). Furthermore, high ADAM8 levels predicted poor patient outcome. Consistently, ADAM8 promoted an aggressive phenotype of TNBC cells in culture. In a mouse orthotopic model, tumors derived from TNBC cells with ADAM8 knockdown failed to grow beyond a palpable size and displayed poor vascularization. Circulating tumor cells and brain metastases were also significantly reduced. Mechanistically, ADAM8 stimulated both angiogenesis through release of VEGF-A and transendothelial cell migration via β1-integrin activation. In vivo, treatment with an anti-ADAM8 antibody from the time of cell inoculation reduced primary tumor burden and metastases. Furthermore, antibody treatment of established tumors profoundly decreased metastases in a resection model. As a non-essential protein under physiological conditions, ADAM8 represents a promising novel target for treatment of TNBCs, which currently lack targeted therapies and frequently progress with fatal dissemination. Subject Category Cancer PMID:24375628

  4. ADAM8 expression in invasive breast cancer promotes tumor dissemination and metastasis.

    PubMed

    Romagnoli, Mathilde; Mineva, Nora D; Polmear, Michael; Conrad, Catharina; Srinivasan, Srimathi; Loussouarn, Delphine; Barillé-Nion, Sophie; Georgakoudi, Irene; Dagg, Áine; McDermott, Enda W; Duffy, Michael J; McGowan, Patricia M; Schlomann, Uwe; Parsons, Maddy; Bartsch, Jörg W; Sonenshein, Gail E

    2014-02-01

    The transmembrane metalloprotease-disintegrin ADAM8 mediates cell adhesion and shedding of ligands, receptors and extracellular matrix components. Here, we report that ADAM8 is abundantly expressed in breast tumors and derived metastases compared to normal tissue, especially in triple-negative breast cancers (TNBCs). Furthermore, high ADAM8 levels predicted poor patient outcome. Consistently, ADAM8 promoted an aggressive phenotype of TNBC cells in culture. In a mouse orthotopic model, tumors derived from TNBC cells with ADAM8 knockdown failed to grow beyond a palpable size and displayed poor vascularization. Circulating tumor cells and brain metastases were also significantly reduced. Mechanistically, ADAM8 stimulated both angiogenesis through release of VEGF-A and transendothelial cell migration via β1-integrin activation. In vivo, treatment with an anti-ADAM8 antibody from the time of cell inoculation reduced primary tumor burden and metastases. Furthermore, antibody treatment of established tumors profoundly decreased metastases in a resection model. As a non-essential protein under physiological conditions, ADAM8 represents a promising novel target for treatment of TNBCs, which currently lack targeted therapies and frequently progress with fatal dissemination.

  5. Expression of ADAMs and their inhibitors in sputum from patients with asthma.

    PubMed

    Paulissen, Geneviève; Rocks, Natacha; Quesada-Calvo, Florence; Gosset, Philippe; Foidart, Jean-Michel; Noel, Agnès; Louis, Renaud; Cataldo, Didier D

    2006-01-01

    ADAMs (a disintegrin and metalloprotease) constitute a family of cell surface proteins containing disintegrin and metalloprotease domains which associate features of adhesion molecules and proteases. ADAMTSs (a disintegrin and metalloprotease with thrombospondin motifs) bear thrombospondin type I motifs in C-terminal extremity, and most of them are secreted proteins. Because genetic studies have shown that ADAM-33 gene polymorphisms are associated with asthma, we designed this study to assess mRNA expression profile of several ADAM and ADAMTS proteases in sputum from patients with asthma and to investigate the relationship between expression of these proteases and asthma-associated inflammation and airway obstruction. mRNA expression profile of selected ADAM and ADAMTS proteinases (ADAM-8, -9, -10, -12, -15, -17, and -33; ADAMTS-1, -2, -15, -16, -17, -18, and -19), their physiological inhibitors TIMP-1 and TIMP-3, and RECK, a membrane-anchored MMP activity regulator, was obtained by RT-PCR analysis performed on cells collected by sputum induction from 21 patients with mild to moderate asthma and 17 healthy individuals. mRNA levels of ADAM-8, ADAM-9, ADAM-12, TIMP-1, and TIMP-3 were significantly increased, whereas mRNA levels coding for ADAMTS-1, ADAMTS-15, and RECK were significantly decreased in patients with asthma compared with control patients. ADAM-8 expression was negatively correlated with the forced expiratory volume at the first second (FEV(1)) (r = -0.57, P < 0.01), whereas ADAMTS-1 and RECK expressions were positively correlated to FEV(1) (r = 0.45, P < 0.05, and r = 0.55, P = 0.01, respectively). We conclude that expression of ADAMs and ADAMTSs and their inhibitors is modulated in airways from patients with asthma and that these molecules may play a role in the pathogenesis of asthma.

  6. SAP97-mediated ADAM10 trafficking from Golgi outposts depends on PKC phosphorylation

    PubMed Central

    Saraceno, C; Marcello, E; Di Marino, D; Borroni, B; Claeysen, S; Perroy, J; Padovani, A; Tramontano, A; Gardoni, F; Di Luca, M

    2014-01-01

    A disintegrin and metalloproteinase 10 (ADAM10) is the major α-secretase that catalyzes the amyloid precursor protein (APP) ectodomain shedding in the brain and prevents amyloid formation. Its activity depends on correct intracellular trafficking and on synaptic membrane insertion. Here, we describe that in hippocampal neurons the synapse-associated protein-97 (SAP97), an excitatory synapse scaffolding element, governs ADAM10 trafficking from dendritic Golgi outposts to synaptic membranes. This process is mediated by a previously uncharacterized protein kinase C phosphosite in SAP97 SRC homology 3 domain that modulates SAP97 association with ADAM10. Such mechanism is essential for ADAM10 trafficking from the Golgi outposts to the synapse, but does not affect ADAM10 transport from the endoplasmic reticulum. Notably, this process is altered in Alzheimer's disease brains. These results help in understanding the mechanism responsible for the modulation of ADAM10 intracellular path, and can constitute an innovative therapeutic strategy to finely tune ADAM10 shedding activity towards APP. PMID:25429624

  7. ADAM12 is a prognostic factor associated with an aggressive molecular subtype of high-grade serous ovarian carcinoma.

    PubMed

    Cheon, Dong-Joo; Li, Andrew J; Beach, Jessica A; Walts, Ann E; Tran, Hang; Lester, Jenny; Karlan, Beth Y; Orsulic, Sandra

    2015-07-01

    ADAM metallopeptidase domain 12 (ADAM12) is a promising biomarker because of its low expression in normal tissues and high expression in a variety of human cancers. However, ADAM12 levels in ovarian cancer have not been well characterized. We previously identified ADAM12 as one of the signature genes associated with poor survival in high-grade serous ovarian carcinoma (HGSOC). Here, we sought to determine if high levels of the ADAM12 protein and/or messenger RNA (mRNA) are associated with clinical variables in HGSOC. We show that high protein levels of ADAM12 in banked preoperative sera are associated with shorter progression-free and overall survival. Tumor levels of ADAM12 mRNA were also associated with shorter progression-free and overall survival as well as with lymphatic and vascular invasion, and residual tumor volume following cytoreductive surgery. The majority of genes co-expressed with ADAM12 in HGSOC were transforming growth factor (TGF)β signaling targets that function in collagen remodeling and cell-matrix adhesion. In tumor sections, the ADAM12 protein and mRNA were expressed in epithelial cancer cells and surrounding stromal cells. In vitro data showed that ADAM12 mRNA levels can be increased by TGFβ signaling and direct contact between epithelial and stromal cells. High tumor levels of ADAM12 mRNA were characteristic of the mesenchymal/desmoplastic molecular subtype of HGSOC, which is known to have the poorest prognosis. Thus, ADAM12 may be a useful biomarker of aggressive ovarian cancer for which standard treatment is not effective.

  8. ADAM 12: A Putative Marker of Oligodendrogliomas?

    PubMed Central

    Kanakis, Dimitrios; Lendeckel, Uwe; Theodosiou, Paraskevi; Dobrowolny, Henrik; Mawrin, Christian; Keilhoff, Gerburg; Bukowska, Alicia; Dietzmann, Knut; Bogerts, Bernhard; Bernstein, Hans-Gert

    2013-01-01

    ADAM 12 (meltrin alpha) belongs to a large family of molecules, consisting of members with both disintegrin and metalloproteinase properties. ADAMs have been implicated in several cell physiological processes including cell adhesion, cell fusion, proteolysis and signalling. ADAM 12 is widely expressed, including skeletal muscle, testis, bone, intestine, heart and kidney. In addition, a variety of tumours show elevated expression of ADAM12; among them being breast-, colon-, gastric- and lung-carcinoma. As to the brain, ADAM 12 has been shown previously to be expressed in rat and human oligodendrocytes. However, little is known about the expression of this protease in brain tumours. This study demonstrates the presence of ADAM 12 in non-neoplastic oligodendroglial cells of normal human brain as well as in neoplastic oligodendroglia and minigemistocytes arising from four pure oligodendrogliomas and three mixed oligoastrocytomas. Double stainings revealed a notable preference of ADAM 12 for the oligodendroglial over astroglial components. The results of immunohistochemistry are in accordance with the results obtained from the RT-PCR, which further demonstrated a mild difference concerning the mRNA concentration of ADAM 12 between similar grades of eight astrocytomas and eight oligodendrogliomas (namely four astrocytomas grade II versus four oligodendrogliomas grade II and four astrocytomas grade III versus four oligodendrogliomas grade III). Both cellular immunostaining for ADAM 12 and ADAM 12 mRNA content decrease with higher histologic grade of the tumour. Surprisingly, the latter parameter (ADAM12 mRNA) showed a significant opposite correlation to the degree of histologic tumour malignancy. From our data showing that ADAM 12 is highly expressed in, but not restricted to, oligodendrogliomas, we conclude that ADAM 12 immunohistochemistry may be a helpful tool in the diagnosis of brain tumours. PMID:23324579

  9. ADAM 12: a putative marker of oligodendrogliomas?

    PubMed

    Kanakis, Dimitrios; Lendeckel, Uwe; Theodosiou, Paraskevi; Dobrowolny, Henrik; Mawrin, Christian; Keilhoff, Gerburg; Bukowska, Alicia; Dietzmann, Knut; Bogerts, Bernhard; Bernstein, Hans-Gert

    2013-01-01

    ADAM 12 (meltrin alpha) belongs to a large family of molecules, consisting of members with both disintegrin and metalloproteinase properties. ADAMs have been implicated in several cell physiological processes including cell adhesion, cell fusion, proteolysis and signalling. ADAM 12 is widely expressed, including skeletal muscle, testis, bone, intestine, heart and kidney. In addition, a variety of tumours show elevated expression of ADAM12; among them being breast-, colon-, gastric- and lung-carcinoma. As to the brain, ADAM 12 has been shown previously to be expressed in rat and human oligodendrocytes. However, little is known about the expression of this protease in brain tumours. This study demonstrates the presence of ADAM 12 in non-neoplastic oligodendroglial cells of normal human brain as well as in neoplastic oligodendroglia and minigemistocytes arising from four pure oligodendrogliomas and three mixed oligoastrocytomas. Double stainings revealed a notable preference of ADAM 12 for the oligodendroglial over astroglial components. The results of immunohistochemistry are in accordance with the results obtained from the RT-PCR, which further demonstrated a mild difference concerning the mRNA concentration of ADAM 12 between similar grades of eight astrocytomas and eight oligodendrogliomas (namely four astrocytomas grade II versus four oligodendrogliomas grade II and four astrocytomas grade III versus four oligodendrogliomas grade III). Both cellular immunostaining for ADAM 12 and ADAM 12 mRNA content decrease with higher histologic grade of the tumour. Surprisingly, the latter parameter (ADAM12 mRNA) showed a significant opposite correlation to the degree of histologic tumour malignancy. From our data showing that ADAM 12 is highly expressed in, but not restricted to, oligodendrogliomas, we conclude that ADAM 12 immunohistochemistry may be a helpful tool in the diagnosis of brain tumours.

  10. Down regulation of ADAM33 as a Predictive Biomarker of Aggressive Breast Cancer

    PubMed Central

    Manica, Graciele C. M.; Ribeiro, Caroline F.; Oliveira, Marco A. S. de; Pereira, Isabela T.; Chequin, Andressa; Ramos, Edneia A. S.; Klassen, Liliane M. B.; Sebastião, Ana Paula M.; Alvarenga, Larissa M.; Zanata, Silvio M.; Noronha, Lucia De; Rabinovich, Iris; Costa, Fabricio F.; Souza, Emanuel M.; Klassen, Giseli

    2017-01-01

    Breast cancer is a heterogeneous disease with differences in its clinical, molecular and biological features. Traditionally, immunohistochemical markers together with clinicopathologic parameters are used to classify breast cancer and to predict disease outcome. Triple-negative breast cancer (TNBC) is a particular type of breast cancer that is defined by a lack of expression of hormonal receptors and the HER2 gene. Most cases of TNBC also have a basal-like phenotype (BLBC) with expression of cytokeratin 5/6 and/or EGFR. A basal marker alone is insufficient for a better understanding of the tumor biology of TNBC. In that regard, the ADAM33 gene is silenced by DNA hypermethylation in breast cancer, which suggests that ADAM33 might be useful as a molecular marker. In the present study, we have produced monoclonal antibodies against the ADAM33 protein and have investigated the role of ADAM33 protein in breast cancer. We used 212 breast tumor samples and lower levels of ADAM33 were correlated with TNBC and basal-like markers. A lower level of ADAM33 was also correlated with shorter overall survival and metastasis-free survival and was considered an independent prognostic factor suggesting that ADAM33 is a novel molecular biomarker of TNBC and BLBC that might be useful as a prognostic factor. PMID:28294120

  11. Down regulation of ADAM33 as a Predictive Biomarker of Aggressive Breast Cancer.

    PubMed

    Manica, Graciele C M; Ribeiro, Caroline F; Oliveira, Marco A S de; Pereira, Isabela T; Chequin, Andressa; Ramos, Edneia A S; Klassen, Liliane M B; Sebastião, Ana Paula M; Alvarenga, Larissa M; Zanata, Silvio M; Noronha, Lucia De; Rabinovich, Iris; Costa, Fabricio F; Souza, Emanuel M; Klassen, Giseli

    2017-03-15

    Breast cancer is a heterogeneous disease with differences in its clinical, molecular and biological features. Traditionally, immunohistochemical markers together with clinicopathologic parameters are used to classify breast cancer and to predict disease outcome. Triple-negative breast cancer (TNBC) is a particular type of breast cancer that is defined by a lack of expression of hormonal receptors and the HER2 gene. Most cases of TNBC also have a basal-like phenotype (BLBC) with expression of cytokeratin 5/6 and/or EGFR. A basal marker alone is insufficient for a better understanding of the tumor biology of TNBC. In that regard, the ADAM33 gene is silenced by DNA hypermethylation in breast cancer, which suggests that ADAM33 might be useful as a molecular marker. In the present study, we have produced monoclonal antibodies against the ADAM33 protein and have investigated the role of ADAM33 protein in breast cancer. We used 212 breast tumor samples and lower levels of ADAM33 were correlated with TNBC and basal-like markers. A lower level of ADAM33 was also correlated with shorter overall survival and metastasis-free survival and was considered an independent prognostic factor suggesting that ADAM33 is a novel molecular biomarker of TNBC and BLBC that might be useful as a prognostic factor.

  12. Regulation of mature ADAM17 by redox agents for L-selectin shedding1

    PubMed Central

    Wang, Yue; Herrera, Amy H.; Li, Ying; Belani, Kiran K.; Walcheck, Bruce

    2008-01-01

    L-selectin is constitutively expressed by neutrophils and plays a key role in directing these cells to sites of inflammation. Upon neutrophil activation, L-selectin is rapidly and efficiently down-regulated from the cell surface by ectodomain shedding. We have directly shown that ADAM17 is a primary and non-redundant sheddase of L-selection by activated neutrophils in vivo. Following cell activation, intracellular signals lead to the induction of ADAM17's enzymatic activity; however, the target of this inducer mechanism remains unclear. Our study provides evidence of an activation mechanism that involves the extracellular region of the mature form of cell surface ADAM17 and not its intracellular region. We demonstrate that the catalytic activity of purified ADAM17 lacking a pro-domain and its intracellular region is diminished under mild reducing conditions by DTT and enhanced by H2O2 oxidation. Moreover, H2O2 reversed ADAM17 inhibition by DTT. The treatment of neutrophils with H2O2 also induced L-selectin shedding in an ADAM17-dependent manner. These findings suggest that thioldisulfide conversion occurring in the extracellular region of ADAM17 may be involved in its activation. An analysis of ADAM17 revealed that within its disintegrin/cysteine-rich region are two highly conserved, vicinal cysteine sulfhydryl motifs (cysteine-X-X-cysteine, CXXC), which are well characterized targets for thiol-disulfide exchange in various other proteins. Using a cell-based ADAM17 reconstitution assay, we demonstrate that the CXXC motifs are critical for L-selectin cleavage. Taken together, our findings suggest that redox modifications of cysteinyl sulfhydryl groups in mature ADAM17 may serve as a mechanism for regulating the shedding of L-selectin following neutrophil stimulation. PMID:19201900

  13. ADAMS: AIRLAB data management system user's guide

    NASA Technical Reports Server (NTRS)

    Conrad, C. L.; Ingogly, W. F.; Lauterbach, L. A.

    1986-01-01

    The AIRLAB Data Management System (ADAMS) is an online environment that supports research at NASA's AIRLAB. ADAMS provides an easy to use interactive interface that eases the task of documenting and managing information about experiments and improves communication among project members. Data managed by ADAMS includes information about experiments, data sets produced, software and hardware available in AIRLAB as well as that used in a particular experiment, and an on-line engineer's notebook. The User's Guide provides an overview of the ADAMS system as well as details of the operations available within ADAMS. A tutorial section takes the user step-by-step through a typical ADAMS session. ADAMS runs under the VAX/VMS operating system and uses the ORACLE database management system and DEC/FMS (the Forms Management System). ADAMS can be run from any VAX connected via DECnet to the ORACLE host VAX. The ADAMS system is designed for simplicity, so interactions within the underlying data management system and communications network are hidden from the user.

  14. Amyotrophic lateral sclerosis mimic syndromes

    PubMed Central

    Ghasemi, Majid

    2016-01-01

    Amyotrophic lateral sclerosis (ALS) misdiagnosis has many broad implications for the patient and the neurologist. Potentially curative treatments exist for certain ALS mimic syndromes, but delay in starting these therapies may have an unfavorable effect on outcome. Hence, it is important to exclude similar conditions. In this review, we discuss some of the important mimics of ALS. PMID:27326363

  15. Erbb2 up-regulation of ADAM12 expression accelerates skin cancer progression.

    PubMed

    Rao, Velidi H; Vogel, Kristen; Yanagida, Jodi K; Marwaha, Nitin; Kandel, Amrit; Trempus, Carol; Repertinger, Susan K; Hansen, Laura A

    2015-10-01

    Solar ultraviolet (UV) radiation can cause severe damage to the skin and is the primary cause of most skin cancer. UV radiation causes DNA damage leading to mutations and also activates the Erbb2/HER2 receptor through indirect mechanisms involving reactive oxygen species. We hypothesized that Erbb2 activation accelerates the malignant progression of UV-induced skin cancer. Following the induction of benign squamous papillomas by UV exposure of v-ras(Ha) transgenic Tg.AC mice, mice were treated topically with the Erbb2 inhibitor AG825 and tumor progression monitored. AG825 treatment reduced tumor volume, increased tumor regression, and delayed the development of malignant squamous cell carcinoma (SCC). Progression to malignancy was associated with increased Erbb2 and ADAM12 (A Disintegin And Metalloproteinase 12) transcripts and protein, while inhibition of Erbb2 blocked the increase in ADAM12 message upon malignant progression. Similarly, human SCC and SCC cell lines had increased ADAM12 protein and transcripts when compared to normal controls. To determine whether Erbb2 up-regulation of ADAM12 contributed to malignant progression of skin cancer, Erbb2 expression was modulated in cultured SCC cells using forced over-expression or siRNA targeting, demonstrating up-regulation of ADAM12 by Erbb2. Furthermore, ADAM12 transfection or siRNA targeting revealed that ADAM12 increased both the migration and invasion of cutaneous SCC cells. Collectively, these results suggest Erbb2 up-regulation of ADAM12 as a novel mechanism contributing to the malignant progression of UV-induced skin cancer. Inhibition of Erbb2/HER2 reduced tumor burden, increased tumor regression, and delayed the progression of benign skin tumors to malignant SCC in UV-exposed mice. Inhibition of Erbb2 suppressed the increase in metalloproteinase ADAM12 expression in skin tumors, which in turn increased migration and tumor cell invasiveness.

  16. Phenotypic diversity of breast cancer-related mutations in metalloproteinase-disintegrin ADAM12.

    PubMed

    Qi, Yue; Duhachek-Muggy, Sara; Li, Hui; Zolkiewska, Anna

    2014-01-01

    Six different somatic missense mutations in the human ADAM12 gene have been identified so far in breast cancer. Five of these mutations involve highly conserved residues in the extracellular domain of the transmembrane ADAM12-L protein. Two of these extracellular mutations, D301H and G479E, have been previously characterized in the context of mouse ADAM12. Three other mutations, T596A, R612Q, and G668A, have been reported more recently, and their effects on ADAM12-L protein structure/function are not known. Here, we show that ADAM12-L bearing the G668A mutation is largely retained in the endoplasmic reticulum in its nascent, full-length form, with an intact N-terminal pro-domain. The T596A and R612Q mutants are efficiently trafficked to the cell surface and proteolytically processed to remove their pro-domains. However, the T596A mutant shows decreased catalytic activity at the cell surface, while the R612Q mutant is fully active and comparable to the wild-type ADAM12-L. The D301H and G479E mutants, consistent with the corresponding D299H and G477E mutants of mouse ADAM12 described earlier, are not proteolytically processed and do not exhibit catalytic activity at the cell surface. Among all six breast cancer-associated mutations in ADAM12-L, mutations that preserve the activity--R612Q and L792F--occur in triple-negative breast cancers, while loss-of-function mutations--D301H, G479E, T596A, and G668A--are found in non-triple negative cancers. This apparent association between the catalytic activity of the mutants and the type of breast cancer supports a previously postulated role of an active ADAM12-L in the triple negative breast cancer disease.

  17. ADAM17 controls endochondral ossification by regulating terminal differentiation of chondrocytes.

    PubMed

    Hall, Katherine C; Hill, Daniel; Otero, Miguel; Plumb, Darren A; Froemel, Dara; Dragomir, Cecilia L; Maretzky, Thorsten; Boskey, Adele; Crawford, Howard C; Selleri, Licia; Goldring, Mary B; Blobel, Carl P

    2013-08-01

    Endochondral ossification is a highly regulated process that relies on properly orchestrated cell-cell interactions in the developing growth plate. This study is focused on understanding the role of a crucial regulator of cell-cell interactions, the membrane-anchored metalloproteinase ADAM17, in endochondral ossification. ADAM17 releases growth factors, cytokines, and other membrane proteins from cells and is essential for epidermal growth factor receptor (EGFR) signaling and for processing tumor necrosis factor alpha. Here, we report that mice lacking ADAM17 in chondrocytes (A17ΔCh) have a significantly expanded zone of hypertrophic chondrocytes in the growth plate and retarded growth of long bones. This abnormality is caused by an accumulation of the most terminally differentiated type of chondrocytes that produces a calcified matrix. Inactivation of ADAM17 in osteoclasts or endothelial cells does not affect the zone of hypertrophic chondrocytes, suggesting that the main role of ADAM17 in the growth plate is in chondrocytes. This notion is further supported by in vitro experiments showing enhanced hypertrophic differentiation of primary chondrocytes lacking Adam17. The enlarged zone of hypertrophic chondrocytes in A17ΔCh mice resembles that described in mice with mutant EGFR signaling or lack of its ligand transforming growth factor α (TGFα), suggesting that ADAM17 regulates terminal differentiation of chondrocytes during endochondral ossification by activating the TGFα/EGFR signaling axis.

  18. Comparative localization of ADAMs 10 and 15 in human cerebral cortex normal aging, Alzheimer disease and Down syndrome.

    PubMed

    Bernstein, Hans-Gert; Bukowska, Alicja; Krell, Dieter; Bogerts, Bernhard; Ansorge, Siegfried; Lendeckel, Uwe

    2003-02-01

    Using immunohistochemical techniques we studied the light microscopic localization of ADAMs (A Disintegrin And Metalloprotease) 10 and 15 in different neocortical areas of the human brain during normal aging, and also in patients with Alzheimer disease (AD) and Down syndrome (DS). ADAM 10, a putative alpha-secretase involved in Notch signaling, was found in neurons of the perinatal cortex. During aging there is an increase in intraneuronal staining intensity and in the number of cortical nerve cells that contain the enzyme. Furthermore, in AD and DS brains ADAM 10 immunoreactivity was associated with diffuse and neuritic plaques. ADAM 15 was detected in perinatal cortical pyramidal cells; during aging there was also an increase in intracellular staining and the number of stained cells per volume (cell density). In AD brains ADAM 15 was seen in a few diffuse plaques. Morphometric analysis revealed a significant reduction of ADAM 10 but not ADAM 15 immunoreactive neurons in AD brains in comparison to controls. Our findings support the idea that ADAM 10 is involved in the pathophysiology of AD and DS. ADAM 15 might be linked to AD via interaction with integrin and/or src protein tyrosine kinases.

  19. Asteroid shape modelling with ADAM

    NASA Astrophysics Data System (ADS)

    Viikinkoski, Matti; Kaasalainen, Mikko; Durech, Josef

    2015-08-01

    Technological advancements have made it possible to obtain highly detailed images of asteroids, yet 3-D shape reconstruction remains a challenge. Shape inversion is an ill-posed inverse problem as systematic errors, shadowing effects due to non-convex features, and the limitations of the imaging systems render the direct inversion impossible. Moreover, the coverage of one observation session alone is seldom sufficient for 3-D reconstruction, necessitating a method for the integration of widely different, complementary data sources into a coherent shape solution.We present a new 3-D shape reconstruction method for asteroid models. ADAM, an acronym for all-data asteroid modelling, is a general procedure for combining disk-resolved observational data into a shape model. ADAM handles all disk-resolved data in a uniform manner via 2-D Fourier Transform. Almost all disk-resolved data sources are supported: adaptive optics and other images, range-Doppler radar data, and thermal infrared interferometry.As case studies, we examine the shape of (41) Daphne using the adaptive optics images and photometry, and create a model of the asteroid 2000 ET70 from the range-Doppler radar images. Finally, we combine ALMA science verification data, adaptive optics images, occultations, and lightcurve data to study the shape of the large main-belt asteroid (3) Juno.

  20. The Historical World of Henry Adams

    ERIC Educational Resources Information Center

    Blaser, Kent

    1976-01-01

    This paper examines Henry Adams' writings on history by considering four topics which comprise the basis of his thinking: politics, religion, sex, and science. Adam's main goal was to make history a means of exploring the most significant dimensions of human being. (Author/RM)

  1. ADAMs family and relatives in cardiovascular physiology and pathology.

    PubMed

    Zhang, Pu; Shen, Mengcheng; Fernandez-Patron, Carlos; Kassiri, Zamaneh

    2016-04-01

    A disintegrin and metalloproteinases (ADAMs) are a family of membrane-bound proteases. ADAM-TSs (ADAMs with thrombospondin domains) are a close relative of ADAMs that are present in soluble form in the extracellular space. Dysregulated production or function of these enzymes has been associated with pathologies such as cancer, asthma, Alzheimer's and cardiovascular diseases. ADAMs contribute to angiogenesis, hypertrophy and apoptosis in a stimulus- and cell type-dependent manner. Among the ADAMs identified so far (34 in mouse, 21 in human), ADAMs 8, 9, 10, 12, 17 and 19 have been shown to be involved in cardiovascular development or cardiomyopathies; and among the 19 ADAM-TSs, ADAM-TS1, 5, 7 and 9 are important in development of the cardiovascular system, while ADAM-TS13 can contribute to vascular disorders. Meanwhile, there remain a number of ADAMs and ADAM-TSs whose function in the cardiovascular system has not been yet explored. The current knowledge about the role of ADAMs and ADAM-TSs in the cardiovascular pathologies is still quite limited. The most detailed studies have been performed in other cell types (e.g. cancer cells) and organs (nervous system) which can provide valuable insight into the potential functions of ADAMs and ADAM-TSs, their mechanism of action and therapeutic potentials in cardiomyopathies. Here, we review what is currently known about the structure and function of ADAMs and ADAM-TSs, and their roles in development, physiology and pathology of the cardiovascular system.

  2. A positive feedback loop between HER2 and ADAM12 in human head and neck cancer cells increases migration and invasion.

    PubMed

    Rao, V H; Kandel, A; Lynch, D; Pena, Z; Marwaha, N; Deng, C; Watson, P; Hansen, L A

    2012-06-07

    Increased activation of epidermal growth factor receptor (EGFR) family members such as HER2/Erbb2 can result in more aggressive disease, resistance to chemotherapy and reduced survival of head and neck squamous cell carcinoma (HNSCC) patients. In order to identify mechanisms through which these receptor tyrosine kinases accelerate tumor progression, the regulation of metalloprotease expression by EGFR family members was investigated in 11 squamous cell carcinoma (SCC) cell lines. HER2 expression was significantly correlated with ADAM12 (A Disintegrin And Metalloprotease 12) expression in these cell lines and was co-expressed in human head and neck cancers. Inhibition of HER2 or EGFR decreased ADAM12 transcripts whereas HER2 transfection upregulated ADAM12 expression. To understand the molecular mechanisms underlying HER2 regulation of ADAM12, we investigated the signaling pathways directing ADAM12 production in SCC cells. Inhibition of phosphatidyl inositol-3-kinase or mammalian target of rapamycin decreased ADAM12 transcripts in HER2-expressing SCC cells, whereas transfection with AKT increased ADAM12 mRNA. Experiments utilizing ADAM12 transfection or siRNA targeting of ADAM12 revealed that the protease increased both the migration and invasiveness of oral SCC cells. Surprisingly, ADAM12 also increased HER2 message, protein levels and activity through an Ets1-dependent mechanism. Collectively, these results reveal a novel positive activation loop between ADAM12 and HER2 that may contribute to HNSCC progression.

  3. ADAM12 localizes with c-Src to actin-rich structures at the cell periphery and regulates Src kinase activity.

    PubMed

    Stautz, Dorte; Sanjay, Archana; Hansen, Matilde Thye; Albrechtsen, Reidar; Wewer, Ulla M; Kveiborg, Marie

    2010-01-01

    ADAM12 is an active metalloprotease playing an important role in tumour progression. Human ADAM12 exists in two splice variants: a long transmembrane form, ADAM12-L, and a secreted form, ADAM12-S. The subcellular localization of ADAM12-L is tightly regulated and involves intracellular interaction partners and signalling proteins. We demonstrate here a c-Src-dependent redistribution of ADAM12-L from perinuclear areas to actin-rich Src-positive structures at the cell periphery, and identified two separate c-Src binding sites in the cytoplasmic tail of ADAM12-L that interact with the SH3 domain of c-Src with different binding affinities. The association between ADAM12-L and c-Src is transient, but greatly stabilized when the c-Src kinase activity is disrupted. In agreement with this observation, kinase-active forms of c-Src induce ADAM12-L tyrosine phosphorylation. Interestingly, ADAM12-L was also found to enhance Src kinase activity in response to external signals, such as integrin engagement. Thus, we suggest that activated c-Src binds, phosphorylates, and redistributes ADAM12-L to specific sites at the cell periphery, which may in turn promote signalling mechanisms regulating cellular processes with importance in cancer.

  4. ADAM12 redistributes and activates MMP-14, resulting in gelatin degradation, reduced apoptosis and increased tumor growth.

    PubMed

    Albrechtsen, Reidar; Kveiborg, Marie; Stautz, Dorte; Vikeså, Jonas; Noer, Julie B; Kotzsh, Alexander; Nielsen, Finn Cilius; Wewer, Ulla M; Fröhlich, Camilla

    2013-10-15

    Matrix metalloproteinases (MMPs), in particular MMP-2, MMP-9 and MMP-14, play a key role in various aspects of cancer pathology. Likewise, ADAMs (a disintegrin and metalloproteinases), including ADAM12, are upregulated in malignant tumors and contribute to the pathology of cancers. Here, we show that there is a positive correlation between MMP-14 and ADAM12 expression in human breast cancer. We demonstrated that in 293-VnR and human breast cancer cells expressing ADAM12 at the cell surface, endogenous MMP-14 was recruited to the cell surface, resulting in its activation. Subsequent to this activation, gelatin degradation was stimulated and tumor cell apoptosis was decreased, with reduced expression of the pro-apoptotic proteins BCL2L11 and BIK. The effect on gelatin degradation was abrogated by inhibition of the MMP-14 activity and appeared to be dependent on cell surface αVβ3 integrin localization, but neither the catalytic activity of ADAM12 nor the cytoplasmic tail of ADAM12 were required. The significance of ADAM12-induced activation of MMP-14 was underscored by a reduction in MMP-14-mediated gelatin degradation and abolition of apoptosis-protective effects by specific monoclonal antibodies against ADAM12. Furthermore, orthotopic implantation of ADAM12-expressing MCF7 cells in nude mice produced tumors with increased levels of activated MMP-14 and confirmed that ADAM12 protects tumor cells against apoptosis, leading to increased tumor progression. In conclusion, our data suggest that a ternary protein complex composed of ADAM12, αVβ3 integrin and MMP-14 at the tumor cell surface regulates the function of MMP-14. This interaction might point to a novel concept for the development of MMP-14-targeting drugs in treating cancer.

  5. ADAM12-directed ectodomain shedding of E-cadherin potentiates trophoblast fusion.

    PubMed

    Aghababaei, M; Hogg, K; Perdu, S; Robinson, W P; Beristain, A G

    2015-12-01

    Trophoblasts, placental cells of epithelial lineage, undergo extensive differentiation to form the cellular components of the placenta. Trophoblast progenitor cell differentiation into the multinucleated syncytiotrophoblast is a key developmental process required for placental function, where defects in syncytiotrophoblast formation and turnover associate with placental pathologies and link to poor pregnancy outcomes. The cellular and molecular processes governing syncytiotrophoblast formation are poorly understood, but require the activation of pathways that direct cell fusion. The protease, A Disintegrin and Metalloproteinase 12 (ADAM12), controls cell fusion in myoblasts and is highly expressed in the placenta localizing to multiple trophoblast populations. However, the importance of ADAM12 in regulating trophoblast fusion is unknown. Here, we describe a function for ADAM12 in regulating trophoblast fusion. Using two distinct trophoblast models of cell fusion, we show that ADAM12 is dynamically upregulated and is under the transcriptional control of protein kinase A. siRNA-directed loss of ADAM12 impedes spontaneous fusion of primary cytotrophoblasts, whereas overexpression of the secreted variant, ADAM12S, potentiates cell fusion in the Bewo trophoblast cell line. Mechanistically, both ectopic and endogenous levels of ADAM12 were shown to control trophoblast fusion through E-cadherin ectodomain shedding and remodeling of intercellular boundaries. This study describes a novel role for ADAM12 in placental development, specifically highlighting its importance in controlling the differentiation of villous cytotrophoblasts into multinucleated cellular structures. Moreover, this work identifies E-cadherin as a novel ADAM12 substrate, and highlights the significance that cell adhesion molecule ectodomain shedding has in normal development.

  6. Recombinant disintegrin domain of ADAM15 inhibits the proliferation and migration of Bel-7402 cells

    SciTech Connect

    Hou, Y.; Chu, M.; Du, F.F.; Lei, J.Y.; Chen, Y.; Zhu, R.Y.; Gong, X.H.; Ma, X.; Jin, J.

    2013-06-14

    Highlights: •rhddADAM15 inhibited the proliferation and migration of Bel-7402 cells. •rhddADAM15 inhibited growth and metastasis of Bel-7402 cells in zebrafish xenograft. •rhddADAM15 induced apoptosis in Bel-7402 cells and somatic cells of zebrafish. •Cell-cycle in Bel-7402 cells showed a partial G{sub 2}/S arrest. •Activity of caspases 8, 9 and 3 was increased in rhddADAM15-treated Bel-7402 cells. -- Abstract: ADAM15 (A Disintegrin And Metalloproteinase 15), a transmembrane protein containing seven domains, interacts with some integrins via its disintegrin domain and overexpresses in many solid tumors. In this study, the effect of the recombinant human disintegrin domain (rhddADAM15) on the proliferation and migration of Bel-7402 cells was evaluated in vitro and in vivo in zebrafish xenografts. rhddADAM15 (4 μM) severely inhibited the proliferation and migration of Bel-7402 cells, inducing a partial G{sub 2}/S arrest and morphological nucleus changes of apoptosis. Moreover, the activity of caspases 8, 9 and 3 in Bel-7402 cells was increased. In addition, the zebrafish was used as a model for apoptosis-induction and tumor-xenograft. rhddADAM15 (1 pM) inhibited the growth and metastasis of Bel-7402 cell xenografts in zebrafish and a lower concentration (0.1 pM) induced severe apoptosis in the somatic cells of zebrafish. In conclusion, our data identified rhddADAM15 as a potent inhibitor of tumor growth and metastasis, making it a promising tool for use in anticancer treatment.

  7. A disintegrin and metalloproteinase 12 (ADAM12) localizes to invasive trophoblast, promotes cell invasion and directs column outgrowth in early placental development.

    PubMed

    Aghababaei, M; Perdu, S; Irvine, K; Beristain, A G

    2014-03-01

    During pregnancy, stromal- and vascular-remodeling trophoblasts serve critical roles in directing placental development acquiring pro-invasive characteristics. The A Disintegrin and Metalloproteinase (ADAM) family of multifunctional proteins direct cellular processes across multiple organ systems via their intrinsic catalytic, cell adhesive and intracellular signaling properties. ADAM12, existing as two distinct splice variants (ADAM12L and ADAM12S), is highly expressed in the human placenta and promotes cell migration and invasion in several tumor cell lines; however, its role in trophoblast biology is unknown. In this study, ADAM12 was localized to anchoring trophoblast columns in first trimester placentas and to highly invasive extracellular matrix-degrading trophoblasts in placental villous explants. The importance of ADAM12 in directing trophoblast invasion was tested using loss-of and gain-of-function strategies, where siRNA-directed knockdown of ADAM12 inhibited trophoblast cell invasion while over-expression promoted migration and invasion in two trophoblastic cell models. In placental villous explant cultures, siRNA-directed loss of ADAM12 significantly dampened trophoblast column outgrowth. Additionally, we provide functional evidence for the ADAM12S variant in promoting trophoblast invasion and column outgrowth through a mechanism requiring its catalytic activity. This is the first study to assign a function for ADAM12 in trophoblast biology, where ADAM12 may play a central role regulating the behavior of invasive trophoblast subsets in early pregnancy. This study also underlines the importance of ADAM12L and ADAM12S in directing cell motility in normal developmental processes outside of cancer, specifically highlighting a potentially important function of ADAM12S in directing early placental development.

  8. Insulin treatment attenuates renal ADAM17 and ACE2 shedding in diabetic Akita mice.

    PubMed

    Salem, Esam S B; Grobe, Nadja; Elased, Khalid M

    2014-03-15

    Angiotensin-converting enzyme 2 (ACE2) is located in several tissues and is highly expressed in renal proximal tubules, where it degrades the vasoconstrictor angiotensin II (ANG II) to ANG-(1-7). Accumulating evidence supports protective roles of ACE2 in several disease states, including diabetic nephropathy. A disintegrin and metalloprotease (ADAM) 17 is involved in the shedding of several transmembrane proteins, including ACE2. Our previous studies showed increased renal ACE2, ADAM17 expression, and urinary ACE2 in type 2 diabetic mice (Chodavarapu H, Grobe N, Somineni HK, Salem ES, Madhu M, Elased KM. PLoS One 8: e62833, 2013). The aim of the present study was to determine the effect of insulin on ACE2 shedding and ADAM17 in type 1 diabetic Akita mice. Results demonstrate increased renal ACE2 and ADAM17 expression and increased urinary ACE2 fragments (≈70 kDa) and albumin excretion in diabetic Akita mice. Immunostaining revealed colocalization of ACE2 with ADAM17 in renal tubules. Renal proximal tubular cells treated with ADAM17 inhibitor showed reduced ACE2 shedding into the media, confirming ADAM17-mediated shedding of ACE2. Treatment of Akita mice with insulin implants for 20 wk normalized hyperglycemia and decreased urinary ACE2 and albumin excretion. Insulin also normalized renal ACE2 and ADAM17 but had no effect on tissue inhibitor of metalloproteinase 3 (TIMP3) protein expression. There was a positive linear correlation between urinary ACE2 and albuminuria, blood glucose, plasma creatinine, glucagon, and triglycerides. This is the first report showing an association between hyperglycemia, cardiovascular risk factors, and increased shedding of urinary ACE2 in diabetic Akita mice. Urinary ACE2 could be used as a biomarker for diabetic nephropathy and as an index of intrarenal ACE2 status.

  9. The Disintegrin and Metalloprotease ADAM12 Is Associated with TGF-β-Induced Epithelial to Mesenchymal Transition.

    PubMed

    Ruff, Michaël; Leyme, Anthony; Le Cann, Fabienne; Bonnier, Dominique; Le Seyec, Jacques; Chesnel, Franck; Fattet, Laurent; Rimokh, Ruth; Baffet, Georges; Théret, Nathalie

    2015-01-01

    The increased expression of the Disintegrin and Metalloprotease ADAM12 has been associated with human cancers, however its role remain unclear. We have previously reported that ADAM12 expression is induced by the transforming growth factor, TGF-β and promotes TGF-β-dependent signaling through interaction with the type II receptor of TGF-β. Here we explore the implication of ADAM12 in TGF-β-mediated epithelial to mesenchymal transition (EMT), a key process in cancer progression. We show that ADAM12 expression is correlated with EMT markers in human breast cancer cell lines and biopsies. Using a non-malignant breast epithelial cell line (MCF10A), we demonstrate that TGF-β-induced EMT increases expression of the membrane-anchored ADAM12L long form. Importantly, ADAM12L overexpression in MCF10A is sufficient to induce loss of cell-cell contact, reorganization of actin cytoskeleton, up-regulation of EMT markers and chemoresistance. These effects are independent of the proteolytic activity but require the cytoplasmic tail and are specific of ADAM12L since overexpression of ADAM12S failed to induce similar changes. We further demonstrate that ADAM12L-dependent EMT is associated with increased phosphorylation of Smad3, Akt and ERK proteins. Conversely, inhibition of TGF-β receptors or ERK activities reverses ADAM12L-induced mesenchymal phenotype. Together our data demonstrate that ADAM12L is associated with EMT and contributes to TGF-β-dependent EMT by favoring both Smad-dependent and Smad-independent pathways.

  10. ADAM8 is selectively upregulated in endothelial cells and is associated with angiogenesis after spinal cord injury in adult mice

    PubMed Central

    Mahoney, Edward T.; Benton, Richard L.; Maddie, Melissa A.; Whittemore, Scott R.; Hagg, Theo

    2009-01-01

    Endothelial cell (EC) loss and subsequent angiogenesis occurs over the first week after spinal cord injury (SCI). To identify molecular mechanisms that could be targeted with intravenous (i.v.) treatments we determined whether transmembrane A Disintegrin And Metalloprotease (ADAM) proteins are expressed in ECs of the injured spinal cord. ADAMs bind to integrins which are important for EC survival and angiogenesis. Female adult C57Bl/6 mice with a spinal cord contusion had progressively more ADAM8 (CD156) immunostaining in blood vessels and individual ECs between 1 and 28 days following injury. Uninjured spinal cords had little ADAM8 staining. The increase in ADAM8 mRNA and protein was confirmed in spinal cord lysates, and ADAM8 mRNA was present in FACS-enriched ECs. ADAM8 co-localized extensively and exclusively with the EC marker PECAM and also with i.v. injected lectins. I.v. injected isolectin B4 (IB4) labels a subpopulation of blood vessels at and within the injury epicenter 3-7 days after injury, coincident with angiogenesis. Both ADAM8 and the proliferation marker Ki-67 were present in IB4-positive microvessels. ADAM8-positive proliferating cells were seen at the leading end of IB4-positive blood vessels. Angiogenesis was confirmed by BrdU incorporation, binding of i.v. injected nucleolin antibodies, and MT1-MMP immunostaining in a subset of blood vessels. These data suggest that ADAM8 is vascular-selective and plays a role in proliferation and/or migration of ECs during angiogenesis following SCI. PMID:19003792

  11. ADAM17 is regulated by a rapid and reversible mechanism that controls access to its catalytic site

    PubMed Central

    Le Gall, Sylvain M.; Maretzky, Thorsten; Issuree, Priya D. A.; Niu, Xiao-Da; Reiss, Karina; Saftig, Paul; Khokha, Rama; Lundell, Daniel; Blobel, Carl P.

    2010-01-01

    Protein ectodomain shedding is crucial for cell–cell interactions because it controls the bioavailability of soluble tumor necrosis factor-α (TNFα) and ligands of the epidermal growth factor (EGF) receptor, and the release of many other membrane proteins. Various stimuli can rapidly trigger ectodomain shedding, yet much remains to be learned about the identity of the enzymes that respond to these stimuli and the mechanisms underlying their activation. Here, we demonstrate that the membrane-anchored metalloproteinase ADAM17, but not ADAM10, is the sheddase that rapidly responds to the physiological signaling pathways stimulated by thrombin, EGF, lysophosphatidic acid and TNFα. Stimulation of ADAM17 is swift and quickly reversible, and does not depend on removal of its inhibitory pro-domain by pro-protein convertases, or on dissociation of an endogenous inhibitor, TIMP3. Moreover, activation of ADAM17 by physiological stimuli requires its transmembrane domain, but not its cytoplasmic domain, arguing against inside–out signaling via cytoplasmic phosphorylation as the underlying mechanism. Finally, experiments with the tight binding hydroxamate inhibitor DPC333, used here to probe the accessibility of the active site of ADAM17, demonstrate that this inhibitor can quickly bind to ADAM17 in stimulated, but not quiescent cells. These findings support the concept that activation of ADAM17 involves a rapid and reversible exposure of its catalytic site. PMID:20980382

  12. Cleavage Site Localization Differentially Controls Interleukin-6 Receptor Proteolysis by ADAM10 and ADAM17

    PubMed Central

    Riethmueller, Steffen; Ehlers, Johanna C.; Lokau, Juliane; Düsterhöft, Stefan; Knittler, Katharina; Dombrowsky, Gregor; Grötzinger, Joachim; Rabe, Björn; Rose-John, Stefan; Garbers, Christoph

    2016-01-01

    Limited proteolysis of the Interleukin-6 Receptor (IL-6R) leads to the release of the IL-6R ectodomain. Binding of the cytokine IL-6 to the soluble IL-6R (sIL-6R) results in an agonistic IL-6/sIL-6R complex, which activates cells via gp130 irrespective of whether the cells express the IL-6R itself. This signaling pathway has been termed trans-signaling and is thought to mainly account for the pro-inflammatory properties of IL-6. A Disintegrin And Metalloprotease 10 (ADAM10) and ADAM17 are the major proteases that cleave the IL-6R. We have previously shown that deletion of a ten amino acid long stretch within the stalk region including the cleavage site prevents ADAM17-mediated cleavage, whereas the receptor retained its full biological activity. In the present study, we show that deletion of a triple serine (3S) motif (Ser-359 to Ser-361) adjacent to the cleavage site is sufficient to prevent IL-6R cleavage by ADAM17, but not ADAM10. We find that the impaired shedding is caused by the reduced distance between the cleavage site and the plasma membrane. Positioning of the cleavage site in greater distance towards the plasma membrane abrogates ADAM17-mediated shedding and reveals a novel cleavage site of ADAM10. Our findings underline functional differences in IL-6R proteolysis by ADAM10 and ADAM17. PMID:27151651

  13. John Quincy Adams's rhetorical crusade for astronomy.

    PubMed

    Portolano, M

    2000-09-01

    Astronomy thrived in Europe during the early nineteenth century, but in the United States a utilitarian mind-set opposed it. John Quincy Adams's oratory in support of American astronomical discovery reached its peak during congressional debate over the Smithsonian Institution (1838-1846). During this debate Adams countered proposals to found a university with plans for an observatory. His addresses to congressional and public audiences about observatories and astronomy were intended to foster interest in the science and encourage the growing astronomical community in America. Although the U.S. Naval Observatory in Washington, D.C., was established before the Smithsonian debate ended, many considered Adams its political father. Adams composed his speeches on astronomy in a systematic manner, following neoclassical principles of rhetoric that he had taught at Harvard University. His speeches both in and outside of Congress show evidence of the rhetorical principles he conscientiously used in the service of astronomy.

  14. Do benzodiazepines mimic reverse-turn structures?

    NASA Astrophysics Data System (ADS)

    Hata, Masayuki; Marshall, Garland R.

    2006-05-01

    The role of benzodiazepine derivatives (BZD) as a privileged scaffold that mimics β-turn structures (Ripka et al. (1993) Tetrahedron 49:3593-3608) in peptide/protein recognition was reexamined in detail. Stable BZD ring conformers were determined with MM3, and experimental reverse-turn structures were extracted from the basis set of protein crystal structures previously defined by Ripka et al. Ideal β-turns were also modeled and similarly compared with BZD conformers. Huge numbers of conformers were generated by systematically scanning the torsional degrees of freedom for BZDs, as well as those of ideal β-turns for comparison. Using these structures, conformers of BZDs were fit to experimental structures as suggested by Ripka et al., or modeled classical β-turn conformers, and the root-mean-square deviation (RMSD) values were calculated for each pairwise comparison. Pairs of conformers with the smallest RMSD values for overlap of the four α-β side-chain orientations were selected. All overlaps of BZD conformers with experimental β-turns yielded one or more comparisons where the least RMSD was significantly small, 0.48-0.86 Å, as previously suggested. Utilizing a different methodology, the overall conclusion that benzodiazepines could serve as reverse-turn mimetics of Ripka et al. is justified. The least RMSD values for the overlap of BZDs and modeled classical β-turns were also less than 1 Å. When comparing BZDs with experimental or classical β-turns, the set of experimental β-turns selected by Ripka et al. fit the BZD scaffolds better than modeled classical β-turns; however, all the experimental β-turns did not fit a particular BZD scaffold better. A single BZD ring conformation, and/or chiral orientation, can mimic some, but not all, of the experimental β-turn structures. BZD has two central ring conformations and one chiral center that explains why the four variations of the BZD scaffold can mimic all types of β-turn structure examined. It was

  15. A Conversation with Adam Heller.

    PubMed

    Heller, Adam; Cairns, Elton J

    2015-01-01

    Adam Heller, Ernest Cockrell Sr. Chair in Engineering Emeritus of the John J. McKetta Department of Chemical Engineering at The University of Texas at Austin, recalls his childhood in the Holocaust and his contributions to science and technology that earned him the US National Medal of Technology and Innovation in a conversation with Elton J. Cairns, Professor of Chemical and Biomolecular Engineering at the University of California, Berkeley. Dr. Heller, born in 1933, describes the enslavement of his father by Hungarians in 1942; the confiscation of his family's home, business, and all its belongings in 1944; and his incarceration in a brick factory with 18,000 Jews who were shipped by the Hungarians to be gassed by Germans in Auschwitz. Dr. Heller and his immediate family survived the Holocaust and arrived in Israel in 1945. He studied under Ernst David Bergmann at the Hebrew University, and then worked at Bell Laboratories and GTE Laboratories, where he headed Bell Lab's Electronic Materials Research Department. At GTE Laboratories, he built in 1966 the first neodymium liquid lasers and in 1973 with Jim Auborn conceived and engineered the lithium thionyl chloride battery, one of the first to be manufactured lithium batteries, which is still in use. After joining the faculty of engineering of The University of Texas at Austin, he cofounded with his son Ephraim Heller TheraSense, now a major part of Abbott Diabetes Care, which produced a microcoulometer that made the monitoring of glucose painless by accurately measuring the blood glucose concentration in 300 nL of blood. He also describes the electrical wiring of enzymes, the basis for Abbott's state-of-the-art continuous glucose monitoring system. He discusses his perspective of reducing the risk of catastrophic global warming in a wealth-accumulating, more-energy-consuming world and provides advice for students entering careers in science or engineering.

  16. ADAM9 promotes lung cancer metastases to brain by a plasminogen activator-based pathway.

    PubMed

    Lin, Chen-Yuan; Chen, Hung-Jen; Huang, Cheng-Chung; Lai, Liang-Chuan; Lu, Tzu-Pin; Tseng, Guan-Chin; Kuo, Ting-Ting; Kuok, Qian-Yu; Hsu, Jennifer L; Sung, Shian-Ying; Hung, Mien-Chie; Sher, Yuh-Pyng

    2014-09-15

    The transmembrane cell adhesion protein ADAM9 has been implicated in cancer cell migration and lung cancer metastasis to the brain, but the underpinning mechanisms are unclear and clinical support has been lacking. Here, we demonstrate that ADAM9 enhances the ability of tissue plasminogen activator (tPA) to cleave and stimulate the function of the promigratory protein CDCP1 to promote lung metastasis. Blocking this mechanism of cancer cell migration prolonged survival in tumor-bearing mice and cooperated with dexamethasone and dasatinib (a dual Src/Abl kinase inhibitor) treatment to enhance cytotoxic treatment. In clinical specimens, high levels of ADAM9 and CDCP1 correlated with poor prognosis and high risk of mortality in patients with lung cancer. Moreover, ADAM9 levels in brain metastases derived from lung tumors were relatively higher than the levels observed in primary lung tumors. Our results show how ADAM9 regulates lung cancer metastasis to the brain by facilitating the tPA-mediated cleavage of CDCP1, with potential implications to target this network as a strategy to prevent or treat brain metastatic disease.

  17. Chromosomal mapping, sequence and transcription analysis of the porcine fertilin beta gene (ADAM2).

    PubMed

    Day, A E; Quilter, C R; Sargent, C A; Mileham, A J

    2003-10-01

    Fertilin beta (ADAM2) forms a part of the heterodimeric surface protein fertilin, found on the plasma membrane of mammalian sperm, and has been implicated in the process of sperm-egg fusion. Analysis of cDNA products obtained from adult porcine testis mRNA has presented a sequence corresponding to 2620 bp of the ADAM2 gene. This sequence contained an open reading frame encoding a 735-amino acid protein and homologous to ADAM2 genes known in other mammalian species. Polymerase chain reaction (PCR) analysis of genomic DNA showed that the 2620 bp of cDNA sequence comprises at least 21 exons and spans approximately 76 kb of genomic DNA, with its size and structure being relatively conserved between mouse, human and pig. Fluorescence in situ hybridization was used to map ADAM2 to chromosome 15 of the pig, using a bacterial artificial chromosome clone from the PigE BAC library. This finding is consistent with comparative mapping experiments performed between pig and human chromosomes. Analysis of nine mRNA samples, by reverse transcriptase-PCR, from different porcine tissues has also suggested that expression of ADAM2 is limited to the testis, a finding that is consistent with other mammalian species.

  18. Soluble Axl is generated by ADAM10-dependent cleavage and associates with Gas6 in mouse serum.

    PubMed

    Budagian, Vadim; Bulanova, Elena; Orinska, Zane; Duitman, Erwin; Brandt, Katja; Ludwig, Andreas; Hartmann, Dieter; Lemke, Greg; Saftig, Paul; Bulfone-Paus, Silvia

    2005-11-01

    Axl receptor tyrosine kinase exists as a transmembrane protein and as a soluble molecule. We show that constitutive and phorbol 12-myristate 13-acetate-induced generation of soluble Axl (sAxl) involves the activity of disintegrin-like metalloproteinase 10 (ADAM10). Spontaneous and inducible Axl cleavage was inhibited by the broad-spectrum metalloproteinase inhibitor GM6001 and by hydroxamate GW280264X, which is capable of blocking ADAM10 and ADAM17. Furthermore, murine fibroblasts deficient in ADAM10 expression exhibited a significant reduction in constitutive and inducible Axl shedding, whereas reconstitution of ADAM10 restored sAxl production, suggesting that ADAM10-mediated proteolysis constitutes a major mechanism for sAxl generation in mice. Partially overlapping 14-amino-acid stretch deletions in the membrane-proximal region of Axl dramatically affected sAxl generation, indicating that these regions are involved in regulating the access of the protease to the cleavage site. Importantly, relatively high circulating levels of sAxl are present in mouse sera in a heterocomplex with Axl ligand Gas6. Conversely, two other family members, Tyro3 and Mer, were not detected in mouse sera and conditioned medium. sAxl is constitutively released by murine primary cells such as dendritic and transformed cell lines. Upon immobilization, sAxl promoted cell migration and induced the phosphorylation of Axl and phosphatidylinositol 3-kinase. Thus, ADAM10-mediated generation of sAxl might play an important role in diverse biological processes.

  19. Soluble Axl Is Generated by ADAM10-Dependent Cleavage and Associates with Gas6 in Mouse Serum†

    PubMed Central

    Budagian, Vadim; Bulanova, Elena; Orinska, Zane; Duitman, Erwin; Brandt, Katja; Ludwig, Andreas; Hartmann, Dieter; Lemke, Greg; Saftig, Paul; Bulfone-Paus, Silvia

    2005-01-01

    Axl receptor tyrosine kinase exists as a transmembrane protein and as a soluble molecule. We show that constitutive and phorbol 12-myristate 13-acetate-induced generation of soluble Axl (sAxl) involves the activity of disintegrin-like metalloproteinase 10 (ADAM10). Spontaneous and inducible Axl cleavage was inhibited by the broad-spectrum metalloproteinase inhibitor GM6001 and by hydroxamate GW280264X, which is capable of blocking ADAM10 and ADAM17. Furthermore, murine fibroblasts deficient in ADAM10 expression exhibited a significant reduction in constitutive and inducible Axl shedding, whereas reconstitution of ADAM10 restored sAxl production, suggesting that ADAM10-mediated proteolysis constitutes a major mechanism for sAxl generation in mice. Partially overlapping 14-amino-acid stretch deletions in the membrane-proximal region of Axl dramatically affected sAxl generation, indicating that these regions are involved in regulating the access of the protease to the cleavage site. Importantly, relatively high circulating levels of sAxl are present in mouse sera in a heterocomplex with Axl ligand Gas6. Conversely, two other family members, Tyro3 and Mer, were not detected in mouse sera and conditioned medium. sAxl is constitutively released by murine primary cells such as dendritic and transformed cell lines. Upon immobilization, sAxl promoted cell migration and induced the phosphorylation of Axl and phosphatidylinositol 3-kinase. Thus, ADAM10-mediated generation of sAxl might play an important role in diverse biological processes. PMID:16227584

  20. An activated form of ADAM10 is tumor selective and regulates cancer stem-like cells and tumor growth

    PubMed Central

    Saha, Nayanendu; Eissman, Moritz F.; Xu, Kai; Llerena, Carmen; Kusebauch, Ulrike; Ding, Bi-Sen; Cao, Zhongwei; Rafii, Shahin; Ernst, Matthias; Scott, Andrew M.; Nikolov, Dimitar B.; Lackmann, Martin

    2016-01-01

    The transmembrane metalloprotease ADAM10 sheds a range of cell surface proteins, including ligands and receptors of the Notch, Eph, and erbB families, thereby activating signaling pathways critical for tumor initiation and maintenance. ADAM10 is thus a promising therapeutic target. Although widely expressed, its activity is normally tightly regulated. We now report prevalence of an active form of ADAM10 in tumors compared with normal tissues, in mouse models and humans, identified by our conformation-specific antibody mAb 8C7. Structure/function experiments indicate mAb 8C7 binds an active conformation dependent on disulfide isomerization and oxidative conditions, common in tumors. Moreover, this active ADAM10 form marks cancer stem-like cells with active Notch signaling, known to mediate chemoresistance. Importantly, specific targeting of active ADAM10 with 8C7 inhibits Notch activity and tumor growth in mouse models, particularly regrowth after chemotherapy. Our results indicate targeted inhibition of active ADAM10 as a potential therapy for ADAM10-dependent tumor development and drug resistance. PMID:27503072

  1. A Staphylococcus aureus Pore-Forming Toxin Subverts the Activity of ADAM10 to Cause Lethal Infection

    PubMed Central

    Inoshima, Ichiro; Inoshima, Naoko; Wilke, Georgia; Powers, Michael; Frank, Karen; Wang, Yang; Wardenburg, Juliane Bubeck

    2011-01-01

    Staphylococcus aureus is a major cause of human disease, responsible for half a million infections and approximately 20,000 deaths per year in the United States alone 1,2. This pathogen secretes α-hemolysin, a pore-forming cytotoxin that contributes to the pathogenesis of pneumonia 3–5. α-hemolysin injures epithelial cells by interacting with its receptor, the zinc-dependent metalloprotease ADAM10 6. We show that mice harboring a conditional disruption of the Adam10 gene in lung epithelium are resistant to lethal pneumonia. Investigation of the molecular mechanism of toxin-receptor function revealed that α-hemolysin upregulates ADAM10 metalloprotease activity in alveolar epithelial cells, resulting in cleavage of the adherens junction protein E-cadherin. Cleavage is associated with disruption of epithelial barrier function, contributing to the pathogenesis of lethal acute lung injury. A metalloprotease inhibitor of ADAM10 prevents E-cadherin cleavage; similarly, E-cadherin proteolysis and barrier disruption is attenuated in ADAM10 knockout mice. Together, these data attest to the function of ADAM10 as the cellular receptor for α-hemolysin. The observation that Hla can usurp the metalloprotease activity of its receptor reveals a novel mechanism of pore-forming cytotoxin action in which pathologic insults are not solely the result of irreversible membrane injury, and defines ADAM10 inhibition as a strategy for disease modification. PMID:21926978

  2. Serological immune response against ADAM10 pro-domain is associated with favourable prognosis in stage III colorectal cancer patients

    PubMed Central

    Álvarez-Fernández, Sheila María; Barbariga, Marco; Cannizzaro, Luca; Cannistraci, Carlo Vittorio; Hurley, Laura; Zanardi, Alan; Conti, Antonio; Sanvito, Francesca; Innocenzi, Anna; Pecorelli, Nicolò; Braga, Marco; Alessio, Massimo

    2016-01-01

    A humoral immune response against aberrant tumor proteins can be elicited in cancer patients, resulting in the production of auto-antibodies (Abs). By serological proteome analysis we identified the surface membrane protein ADAM10, a metalloproteinase that has a role in epithelial-tumor progression and invasion, as a target of the immune response in colorectal cancer (Crc). A screening carried out on the purified protein using testing cohorts of sera (Crc patients n = 57; control subjects n = 39) and validation cohorts of sera (Crc patients n = 49; control subjects n = 52) indicated that anti-ADAM10 auto-Abs were significantly induced in a large group (74%) of colon cancer patients, in particular in patients at stage II and III of the disease. Interestingly, in Crc patients classified as stage III disease, the presence of anti-ADAM10 auto-Abs in the sera was associated with a favourable follow-up with a significant shifting of the recurrence-free survival median time from 23 to 55 months. Even though the ADAM10 protein was expressed in Crc regardless the presence of auto-Abs, the immature/non-functional isoform of ADAM10 was highly expressed in the tumor of anti-ADAM10-positive patients and was the isoform targeted by the auto-Abs. In conclusion, the presence of anti-ADAM10 auto-Abs seems to reflect the increased tumor expression of the immunogenic immature-ADAM10 in a group of Crc patients, and is associated with a favourable prognosis in patients at stage III of the disease. PMID:27517630

  3. ADAM: automated data management for research datasets

    PubMed Central

    Woodbridge, Mark; Tomlinson, Christopher D.; Butcher, Sarah A.

    2013-01-01

    Existing repositories for experimental datasets typically capture snapshots of data acquired using a single experimental technique and often require manual population and continual curation. We present a storage system for heterogeneous research data that performs dynamic automated indexing to provide powerful search, discovery and collaboration features without the restrictions of a structured repository. ADAM is able to index many commonly used file formats generated by laboratory assays and therefore offers specific advantages to the experimental biology community. However, it is not domain specific and can promote sharing and re-use of working data across scientific disciplines. Availability and implementation: ADAM is implemented using Java and supported on Linux. It is open source under the GNU General Public License v3.0. Installation instructions, binary code, a demo system and virtual machine image and are available at http://www.imperial.ac.uk/bioinfsupport/resources/software/adam. Contact: m.woodbridge@imperial.ac.uk PMID:23109181

  4. Proceedings of the 1989 ADAM Workshop

    NASA Astrophysics Data System (ADS)

    Chipperfield, Alan

    ADAM is now a major software project; it provides a fully integrated environment for both data reduction and data acquisition. It is being used in Hawaii, Australia and the Canary Islands, as well as the UK, and has been adopted by Starlink as the environment in which Starlink data reduction software should run. One of the most remarkable things about ADAM is that it has been developed as a co-operative effort between groups that are spread across the world. Although the initial system came out of RGO, and ROE provided by far the major effort in designing and implementing the VAX version, various parts of what is now regarded as 'ADAM' have also come from other establishments. Co-ordinating a project being developed in this way is not an easy job, but the somewhat varied parentage of ADAM - although sometimes an administrative nightmare - is also one of its strengths; it is not a system developed in one place to serve the specific needs of that one place. One way in which this development is co-ordinated is by a series of workshops. These have taken place at about 18 month intervals since the first one in late 1985. The workshops are attended by people actively developing and/or making extensive use of ADAM, and provide a forum for detailed discussion of the problems in the current system and plans for its extension. The 1989 ADAM Workshop was held at Cosener's House, Abingdon from 3rd to 7th July 1989. An 'Open Meeting' was held on Friday 30th June at RAL to enable members of the Starlink community to provide input to the Workshop discussions. Before the previous workshop, in Hawaii, a trend had started to emerge for different establishments to plug the gaps in ADAM (which at the time was missing a number of important facilities) with local solutions. The Hawaii Workshop consolidated these local extensions, adopting some and rejecting others. As a result, ADAM, as reviewed by this third workshop, was a much more complete and uniform system, and it was possible to

  5. The ADAM workshops and meeting summary

    NASA Astrophysics Data System (ADS)

    Chipperfield, Alan J.

    1990-01-01

    ADAM is now a major software project; it provides a fully integrated environment for both data reduction and data acquisition. It is being used in Hawaii, Australia and the Canary Islands, as well as the UK, and has been adopted by Starlink as the environment in which Starlink data reduction software should run. One of the most remarkable things about ADAM is that it has been developed as a co-operative effort between groups that are spread across the world. Although the initial system came out of RGO, and ROE provided by far the major effort in designing and implementing the VAX version, various parts of what is now regarded as 'ADAM' have also come from other establishments. Co-ordinating a project being developed in this way is not an easy job, but the somewhat varied parentage of ADAM - although sometimes an administrative nightmare - is also one of its strengths; it is not a system developed in one place to serve the specific needs of that one place. One way in which this development is co-ordinated is by a series of workshops. These have taken place at about 18 month intervals since the first one in late 1985. The workshops are attended by people actively developing and/or making extensive use of ADAM, and provide a forum for detailed discussion of the problems in the current system and plans for its extension. The 1989 ADAM Workshop was held at Cosener's House, Abingdon from 3rd to 7th July 1989. An 'Open Meeting' was held on Friday 30th June at RAL to enable members of the Starlink community to provide input to the Workshop discussions. Before the previous workshop, in Hawaii, a trend had started to emerge for different establishments to plug the gaps in ADAM (which at the time was missing a number of important facilities) with local solutions. The Hawaii Workshop consolidated these local extensions, adopting some and rejecting others. As a result, ADAM, as reviewed by this third workshop, was a much more complete and uniform system, and it was possible to

  6. Glioma-Derived ADAM10 Induces Regulatory B Cells to Suppress CD8+ T Cells

    PubMed Central

    Li, Wen-sheng; Luo, Lun; Huang, Zhen-chao; Guo, Ying

    2014-01-01

    CD8+ T cells play an important role in the anti-tumor activities of the body. The dysfunction of CD8+ T cells in glioma is unclear. This study aims to elucidate the glioma cell-derived ADAM10 (A Disintegrin and metalloproteinase domain-containing protein 10) in the suppression of CD8+ effector T cells by the induction of regulatory B cells. In this study, glioma cells were isolated from surgically removed glioma tissue and stimulated by Phorbol myristate acetage (PMA) in the culture. The levels of ADAM10 in the culture were determined by enzyme-linked immunosorbent assay. Immune cells were assessed by flow cytometry. The results showed that the isolated glioma cells express ADAM10, which was markedly up regulated after stimulated with PMA. The glioma-derived ADAM10 induced activated B cells to differentiate into regulatory B cells, the later suppressed CD8+ T cell proliferation as well as the induced regulatory T cells, which also showed the immune suppressor effect on CD8+ effector T cell proliferation. In conclusion, glioma cells produce ADAM10 to induce Bregs; the latter suppresses CD8+ T cells and induces Tregs. PMID:25127032

  7. A Disintegrin and Metalloprotease (ADAM): Historical Overview of Their Functions

    PubMed Central

    Giebeler, Nives; Zigrino, Paola

    2016-01-01

    Since the discovery of the first disintegrin protein from snake venom and the following identification of a mammalian membrane-anchored metalloprotease-disintegrin implicated in fertilization, almost three decades of studies have identified additional members of these families and several biochemical mechanisms regulating their expression and activity in the cell. Most importantly, new in vivo functions have been recognized for these proteins including cell partitioning during development, modulation of inflammatory reactions, and development of cancers. In this review, we will overview the a disintegrin and metalloprotease (ADAM) family of proteases highlighting some of the major research achievements in the analysis of ADAMs’ function that have underscored the importance of these proteins in physiological and pathological processes over the years. PMID:27120619

  8. Women in History--Abigail Adams: Life, Accomplishments, and Ideas

    ERIC Educational Resources Information Center

    Kenan, Sharon K.

    2008-01-01

    This article profiles the life, accomplishments, and ideas of Abigail Adams. Born in 1944, Adams lacked a formal education, but she more than made up for that shortcoming with her love of reading, especially literature, and her interests in politics and events surrounding the young colonies. Adams was supportive of the advancement of women. She…

  9. Adam Smith, Religion, and Tuition Tax Credits.

    ERIC Educational Resources Information Center

    Alexander, Kern

    1983-01-01

    Examines tuition tax credit programs in framework of Adam Smith's ideas on the economic impact of established churches. Finds that tuition tax credits would amount to state expenditures to relieve the financial burden of parochial school parents and would allow churches to invest commercially to maintain their charitable functions. (JW)

  10. Adam Smith and the Rhetoric of Style.

    ERIC Educational Resources Information Center

    Moran, Michael G.

    Historians of rhetoric have generally accepted the view that Adam Smith rejected the principles of classical rhetoric. However, while there can be no doubt that Smith greatly truncated the five classical arts of rhetoric (invention, arrangement, style, memory, and delivery) by reducing his concerns largely to style and arrangement, he did not…

  11. Paraprofessional of the Year 2009: Tina Adams

    ERIC Educational Resources Information Center

    Berry, John N., III

    2009-01-01

    There is no doubt among the staff and managers at North Carolina State University (NCSU) Libraries, Raleigh, that advanced library technician Tina Adams deserves to be the winner of the "Library Journal's "Paraprofessional of the Year Award for 2009." "Certainly this library has never seen anyone like her before, not in my nine…

  12. Propagandist of the Revolution: Samuel Adams.

    ERIC Educational Resources Information Center

    Scanlon, Thomas M.

    This paper explores Samuel Adam's role as perhaps the most important propagandist of the American Revolution and his efforts to exploit Great Britain's mistakes and to engender in the American colonists a love of liberty and a fear that Great Britain, if not resisted, would replace that liberty with tyranny. Suggesting that the Revolutionary War…

  13. Possible Binary Lightcurve for 3145 Walter Adams

    NASA Astrophysics Data System (ADS)

    Owings, Larry E.; Warner, Brian D.; Pravec, Petr; Kusnirak, Peter

    2011-01-01

    Lightcurve observations have yielded period determinations for asteroid 3145 Walter Adams. A primary period of 2.7113 ± 0.0001 hr, amplitude of 0.10 ± 0.05, and a possible secondary period of about 17.4 hr. The estimated diameter ratio is D2/D1 = 0.22 ± 0.02.

  14. ADAM10 mediates N-cadherin ectodomain shedding during retinal ganglion cell differentiation in primary cultured retinal cells from the developing chick retina.

    PubMed

    Paudel, Sharada; Kim, Yeoun-Hee; Huh, Man-Il; Kim, Song-Ja; Chang, Yongmin; Park, Young Jeung; Lee, Kyoo Won; Jung, Jae-Chang

    2013-04-01

    Here, we examined the role of ADAM10 during retinal cell differentiation in retinal sections and in vitro cultures of developing chick retinal cells from embryonic day 6 (ED6). Immunohistochemistry showed that ADAM10 is abundantly expressed in the inner zone of neuroblastic layer at ED5, and it becomes more highly expressed in the ganglion cell layer at ED7 and ED9. Western blotting confirmed that ADAM10 was expressed as an inactive pro-form that was processed to a shorter, active form in control cultured cells, but in cultures treated with an ADAM10 inhibitor (GI254023X) and ADAM10-specific siRNA, the level of mature ADAM10 decreased. Phase-contrast microscopy showed that long neurite extensions were present in untreated cultures 24 h after plating, whereas cultures treated with GI254023X showed significant decreases in neurite extension. Immunofluorescence staining revealed that there were far fewer differentiated ganglion cells in ADAM10 siRNA and GI254023X-treated cultures compared to controls, whereas the photoreceptor cells were unaltered. The Pax6 protein was more strongly detected in the differentiated ganglion cells of control cultures compared to ADAM10 siRNA and GI254023X-treated cultures. N-cadherin ectodomain shedding was apparent in control cultures after 24 h, when ganglion cell differentiation was observed, but ADAM10 siRNA and GI254023X treatment inhibited these processes. In contrast, N-cadherin staining was strongly detected in photoreceptor cells regardless of ADAM10 siRNA and GI254023X treatment. Taken together, these data indicate that the inhibition of ADAM10 can inhibit Pax6 expression and N-cadherin ectodomain shedding in retinal cells, possibly affecting neurite outgrowth and ganglion cell differentiation.

  15. Heparan sulfate regulates ADAM12 through a molecular switch mechanism.

    PubMed

    Sørensen, Hans Peter; Vivès, Romain R; Manetopoulos, Christina; Albrechtsen, Reidar; Lydolph, Magnus C; Jacobsen, Jonas; Couchman, John R; Wewer, Ulla M

    2008-11-14

    The disintegrin and metalloproteases (ADAMs) are emerging as therapeutic targets in human disease, but specific drug design is hampered by potential redundancy. Unlike other metzincins, ADAM prodomains remain bound to the mature enzyme to regulate activity. Here ADAM12, a protease that promotes tumor progression and chondrocyte proliferation in osteoarthritic cartilage, is shown to possess a prodomain/catalytic domain cationic molecular switch, regulated by exogenous heparan sulfate and heparin but also endogenous cell surface proteoglycans and the polyanion, calcium pentosan polysulfate. Sheddase functions of ADAM12 are regulated by the switch, as are proteolytic functions in placental tissue and sera of pregnant women. Moreover, human heparanase, an enzyme also linked to tumorigenesis, can promote ADAM12 sheddase activity at the cell surface through cleavage of the inhibitory heparan sulfate. These data present a novel concept that might allow targeting of ADAM12 and suggest that other ADAMs may have specific regulatory activity embedded in their prodomain and catalytic domain structures.

  16. Bone tumor mimics: avoiding misdiagnosis.

    PubMed

    Gould, C Frank; Ly, Justin Q; Lattin, Grant E; Beall, Douglas P; Sutcliffe, Joseph B

    2007-01-01

    Whether discovered incidentally or as part of a focused diagnostic evaluation, the finding of a benign osseous lesion that has radiologic features resembling a bone tumor is not uncommon. Some of the more common benign and nonneoplastic entities that can sometimes be confused with tumors are the following: cortical desmoid, Brodie abscess, synovial herniation pit, pseudocyst, enostosis, intraosseous ganglion cyst, fibrous dysplasia, stress fracture, avulsion fracture (healing stage), bone infarct, myositis ossificans, brown tumor, and subchondral cyst. Accurate diagnosis and management of these lesions require a basic understanding of their epidemiology, clinical presentations, anatomic distributions, imaging features, differential considerations, and therapeutic options. This in-depth review of 13 potential bone tumor mimics will assist the radiologist in correctly identifying these benign lesions and in avoiding misdiagnosis and related morbidity. This review will also aid the radiologist in making appropriate recommendations to the referring physician for management or further imaging.

  17. ADAM-9 is a novel mediator of tenascin-C-stimulated invasiveness of brain tumor–initiating cells

    PubMed Central

    Sarkar, Susobhan; Zemp, Franz J.; Senger, Donna; Robbins, Stephen M.; Yong, V. Wee

    2015-01-01

    Background Tenascin-C (TNC), an extracellular matrix protein overexpressed in malignant gliomas, stimulates invasion of conventional glioma cell lines (U251, U87). However, there is a dearth of such information on glioma stemlike cells. Here, we have addressed whether and how TNC may regulate the invasiveness of brain tumor–initiating cells (BTICs) that give rise to glioma progenies. Methods Transwell inserts coated with extracellular matrix proteins were used to determine the role of TNC in BTIC invasion. Microarray analysis, lentiviral constructs, RNA interference-mediated knockdown, and activity assay ascertained the role of proteases in TNC-stimulated BTIC invasion in culture. Involvement of proteases was validated using orthotopic brain xenografts in mice. Results TNC stimulated BTIC invasiveness in a metalloproteinase-dependent manner. A global gene expression screen identified the metalloproteinase ADAM-9 as a potential regulator of TNC-stimulated BTIC invasiveness, and this was corroborated by an increase of ADAM-9 protein in 4 glioma patient–derived BTIC lines. Notably, RNA interference to ADAM-9, as well as inhibition of mitogen-activated protein kinase 8 (c-Jun NH2-terminal kinase), attenuated TNC-stimulated ADAM-9 expression, proteolytic activity, and BTIC invasiveness. The relevance of ADAM-9 to tumor invasiveness was validated using resected human glioblastoma specimens and orthotopic xenografts where elevation of ADAM-9 and TNC expression was prominent at the invasive front of the tumor. Conclusions This study has identified TNC as a promoter of the invasiveness of BTICs through a mechanism involving ADAM-9 proteolysis via the c-Jun NH2-terminal kinase pathway. PMID:25646025

  18. Novel Gbeta Mimic Kelch Proteins Gpb1 and Gpb2 Connect G-Protein Signaling to Ras Via Yeast Neurofibromin Homologs Ira 1 and Ira 2: A Model for Human NF1

    DTIC Science & Technology

    2005-03-01

    in a decrease of the RasGAP Iral/2 proteins and consequently to an increase in the GTP bound form of Ras, which is the active form of Ras and...essential for membrane localization and function fusion protein exhibited a decreased level of myristoylation and required for palmitoylation, and...or when Gpbl /2 were overexpressed. As a!., 2000). Ethanol and glycerol are structurally unrelated F3 shown in Figure 3, A and B, Gpa2 membrane

  19. ADAM10 Cell Surface Expression but Not Activity Is Critical for Staphylococcus aureus α-Hemolysin-Mediated Activation of the NLRP3 Inflammasome in Human Monocytes.

    PubMed

    Ezekwe, Ejiofor A D; Weng, Chengyu; Duncan, Joseph A

    2016-03-30

    The Staphylococcus aureus toxin, α-hemolysin, is an important and well-studied virulence factor in staphylococcal infection. It is a soluble monomeric protein that, once secreted by the bacterium, forms a heptameric pore in the membrane of a broad range of host cell types. Hemolysin was recently discovered to bind and activate a disintegrin and metalloprotease 10 (ADAM10). In epithelial and endothelial cells, ADAM10 activation is required for the toxin's activity against these cells. In host monocytic cells, α-hemolysin activates the nucleotide-binding domain and leucine-rich repeat containing gene family, pyrin domain containing 3 (NLRP3) inflammasome leading to production of pro-inflammatory cytokines and cell death. We now show that ADAM10 is critical for α-hemolysin-mediated activation of the NLRP3 inflammasome in human monocytes as siRNA knockdown or chemical blockade of ADAM10-α-hemolysin interaction leads to diminished inflammasome activation and cell death by reducing the available ADAM10 on the cell surface. Unlike epithelial cell and endothelial cell damage, which requires α-hemolysin induced ADAM10 activation, ADAM10 protease activity was not required for NLRP3 inflammasome activation. This work confirms the importance of ADAM10 in immune activation by α-hemolysin, but indicates that host cell signal induction by the toxin is different between host cell types.

  20. A1 adenosine receptor–stimulated exocytosis in bladder umbrella cells requires phosphorylation of ADAM17 Ser-811 and EGF receptor transactivation

    PubMed Central

    Prakasam, H. Sandeep; Gallo, Luciana I.; Li, Hui; Ruiz, Wily G.; Hallows, Kenneth R.; Apodaca, Gerard

    2014-01-01

    Despite the importance of ADAM17-dependent cleavage in normal biology and disease, the physiological cues that trigger its activity, the effector pathways that promote its function, and the mechanisms that control its activity, particularly the role of phosphorylation, remain unresolved. Using native bladder epithelium, in some cases transduced with adenoviruses encoding small interfering RNA, we observe that stimulation of apically localized A1 adenosine receptors (A1ARs) triggers a Gi-Gβγ-phospholipase C-protein kinase C (PKC) cascade that promotes ADAM17-dependent HB-EGF cleavage, EGFR transactivation, and apical exocytosis. We further show that the cytoplasmic tail of rat ADAM17 contains a conserved serine residue at position 811, which resides in a canonical PKC phosphorylation site, and is phosphorylated in response to A1AR activation. Preventing this phosphorylation event by expression of a nonphosphorylatable ADAM17S811A mutant or expression of a tail-minus construct inhibits A1AR-stimulated, ADAM17-dependent HB-EGF cleavage. Furthermore, expression of ADAM17S811A in bladder tissues impairs A1AR-induced apical exocytosis. We conclude that adenosine-stimulated exocytosis requires PKC- and ADAM17-dependent EGFR transactivation and that the function of ADAM17 in this pathway depends on the phosphorylation state of Ser-811 in its cytoplasmic domain. PMID:25232008

  1. ADAM10 Cell Surface Expression but Not Activity Is Critical for Staphylococcus aureus α-Hemolysin-Mediated Activation of the NLRP3 Inflammasome in Human Monocytes

    PubMed Central

    Ezekwe, Ejiofor A.D.; Weng, Chengyu; Duncan, Joseph A.

    2016-01-01

    The Staphylococcus aureus toxin, α-hemolysin, is an important and well-studied virulence factor in staphylococcal infection. It is a soluble monomeric protein that, once secreted by the bacterium, forms a heptameric pore in the membrane of a broad range of host cell types. Hemolysin was recently discovered to bind and activate a disintegrin and metalloprotease 10 (ADAM10). In epithelial and endothelial cells, ADAM10 activation is required for the toxin’s activity against these cells. In host monocytic cells, α-hemolysin activates the nucleotide-binding domain and leucine-rich repeat containing gene family, pyrin domain containing 3 (NLRP3) inflammasome leading to production of pro-inflammatory cytokines and cell death. We now show that ADAM10 is critical for α-hemolysin-mediated activation of the NLRP3 inflammasome in human monocytes as siRNA knockdown or chemical blockade of ADAM10-α-hemolysin interaction leads to diminished inflammasome activation and cell death by reducing the available ADAM10 on the cell surface. Unlike epithelial cell and endothelial cell damage, which requires α-hemolysin induced ADAM10 activation, ADAM10 protease activity was not required for NLRP3 inflammasome activation. This work confirms the importance of ADAM10 in immune activation by α-hemolysin, but indicates that host cell signal induction by the toxin is different between host cell types. PMID:27043625

  2. Molecular Mimics of the Tumour Antigen MUC1

    PubMed Central

    James, Tharappel C.; Bond, Ursula

    2012-01-01

    A key requirement for the development of cancer immunotherapy is the identification of tumour-associated antigens that are differentially or exclusively expressed on the tumour and recognized by the host immune system. However, immune responses to such antigens are often muted or lacking due to the antigens being recognized as “self”, and further complicated by the tumour environment and regulation of immune cells within. In an effort to circumvent the lack of immune responses to tumour antigens, we have devised a strategy to develop potential synthetic immunogens. The strategy, termed mirror image phage display, is based on the concept of molecular mimicry as demonstrated by the idiotype/anti-idiotype paradigm in the immune system. Here as ‘proof of principle’ we have selected molecular mimics of the well-characterised tumour associated antigen, the human mucin1 protein (MUC1) from two different peptide phage display libraries. The putative mimics were compared in structure and function to that of the native antigen. Our results demonstrate that several of the mimic peptides display T-cell stimulation activity in vitro when presented by matured dendritic cells. The mimic peptides and the native MUC1 antigenic epitopes can cross-stimulate T-cells. The data also indicate that sequence homology and/or chemical properties to the original epitope are not the sole determining factors for the observed immunostimulatory activity of the mimic peptides. PMID:23166757

  3. Cloning and expression of ADAM-related metalloproteases in equine laminitis.

    PubMed

    Coyne, Michael J; Cousin, Hélène; Loftus, John P; Johnson, Philip J; Belknap, James K; Gradil, Carlos M; Black, Samuel J; Alfandari, Dominique

    2009-06-15

    Equine laminitis is a debilitating disease affecting the digital laminae that suspend the distal phalanx within the hoof. While the clinical progression of the disease has been well documented, the molecular events associated with its pathogenesis remain largely unknown. Using real time quantitative PCR (RT-qPCR), we have investigated the expression of genes coding for proteins containing a Disintegrin and Metalloprotease domain (ADAM), as well as genes encoding the natural inhibitors of these enzymes (tissue inhibitor of metalloprotease; TIMP) in horses with naturally-acquired (acute, chronic and aggravated chronic clinical cases) or experimentally-induced (black walnut extract (BWE) and starch gruel models) laminitis. Changes in expression of these enzymes and regulators may underlie the pathologic remodeling of lamellar tissue in laminitis. Genes encoding ADAMs involved in inflammation (ADAM-10 and ADAM-17), as well as those implicated in arthritis (ADAMTS-1, ADAMTS-4 and ADAMTS-5) were cloned, and the sequences used to generate specific oligonucleotide primers for the RT-qPCR experiments. Our results show that genes encoding ADAM-10 and ADAM-17 were not induced in most laminitic animals, whereas ADAMTS-4 gene expression was strongly upregulated in nearly all horses with experimentally-induced and naturally-acquired laminitis. The expression of matrix metalloproteases (MMP)-9 and ADAMTS-5 was also increased in many of the laminitic horses. In addition, TIMP-2 gene expression was decreased in most laminitic horses, whereas expression of genes encoding other TIMPs, namely TIMP-1 and TIMP-3, was randomly increased or decreased in the various models. We conclude that increased expression of lamellar ADAMTS-4 is a common feature of laminitis consistent with a central role of the gene product in the pathophysiology of the disease.

  4. IL-1β and ADAM17 are central regulators of β-defensin expression in Candida esophagitis.

    PubMed

    Pahl, Rene; Brunke, Gabriele; Steubesand, Nadine; Schubert, Sabine; Böttner, Martina; Wedel, Thilo; Jürgensen, Christian; Hampe, Jochen; Schäfer, Heiner; Zeissig, Sebastian; Schreiber, Stefan; Rosenstiel, Philip; Reiss, Karina; Arlt, Alexander

    2011-04-01

    Candida albicans resides on epithelial surfaces as part of the physiological microflora. However, under certain conditions, it may cause life-threatening infections, including Candida sepsis. We have recently shown that human β-defensins (hBDs) hBD-2 and hBD-3 are upregulated in Candida esophagitis and that this antifungal host response is distinctly regulated by NF-κB and MAPK/activator protein-1 (AP-1) pathways. Here, we show that C. albicans induces hBD-2 through an autocrine IL-1β loop and that activation of the epidermal growth factor receptor (EGFR) by endogenous transforming growth factor-α (TGF-α) is a crucial event in the induction of hBD-3. To further dissect upstream signaling events, we investigated expression of the central sheddases for EGFR ligands ADAM10 and ADAM17 in the healthy and infected esophagus. Next, we used pharmaceutical inhibitors and small-interfering RNA-mediated knock down of ADAM10 and ADAM17 to reveal that ADAM17-induced shedding of TGF-α is a crucial step in the induction of hBD-3 expression in response to Candida infection. In conclusion, we describe for the first time an autocrine IL-1β loop responsible for the induction of hBD-2 expression and an ADAM17-TGF-α-EGFR-MAPK/AP-1 pathway leading to hBD-3 upregulation in the course of a Candida infection of the esophagus.

  5. Molecular Signals Elicited by GPCR Agonists in Hypertension, Cardiovascular Remodeling: Are MMPs and ADAMs Elusive Therapeutic Targets?

    PubMed Central

    Wang, Xiang; Bosonea, Ana-Maria; Odenbach, Jeffrey; Fernandez-Patron, Carlos

    2014-01-01

    Hypertension, the condition characterized by sustained elevated blood pressure, affects over 25% of adults in developed countries and is accompanied by pathological cardiac remodeling (i.e., hypertrophy and fibrosis), thus being a major risk factor for cardiac failure. Life style, the environment, genetic factors, diabetes or obesity can all promote development and progression of hypertension associated cardiovascular disease in part because these conditions induce an excess production of pro-hypertensive, pro-hypertrophic and pro-fibrotic agonists. Here we review signaling pathways shared by major agonists including angiotensin II, catecholamines and endothelins. At the cellular level, these agonists initiate disease signaling by activating cognate G protein-coupled receptors (GPCRs). Early events in agonist-signaling include Ca2+ release from intracellular stores, Ca2+ uptake from extracellular millieu into cells and reactive oxygen species (ROS) generation by NADPH oxidase. ROS production in turn contributes to activation of matrix metalloproteinases (MMPs) and ‘a disintegrin and metalloproteinases’ (ADAMs). Activated MMPs and ADAMs cleave growth factors, cytokines as well as cell surface receptors, including GPCRs. Excessive activation of MMPs and ADAMs links agonist receptors with transcription and translation of disease-associated genes, including those of MMPs and ADAMs. Recent research indicates a complex and dynamic regulation of MMPs and ADAMs activity and expression by agonists, which poses a significant challenge to strategies aiming at targeting specific MMPs or ADAMs in cardiovascular disease. PMID:24976815

  6. Recombinant disintegrin domain of human ADAM9 inhibits migration and invasion of DU145 prostate tumor cells

    PubMed Central

    Martin, Ana Carolina Baptista Moreno; Cardoso, Ana Carolina Ferreira; Selistre-de-Araujo, Heloisa Sobreiro; Cominetti, Márcia Regina

    2015-01-01

    One of the most important features of malignant cells is their capacity to invade adjacent tissues and metastasize to distant organs. This process involves the creation, by tumor and stroma cells, of a specific microenvironment, suitable for proliferation, migration and invasion of tumor cells. The ADAM family of proteins has been involved in these processes. This work aimed to investigate the role of the recombinant disintegrin domain of the human ADAM9 (rADAM9D) on the adhesive and mobility properties of DU145 prostate tumor cells. rADAM9D was able to support DU145 cell adhesion, inhibit the migration of DU145 cells, as well as the invasion of this cell line through matrigel in vitro. Overall this work demonstrates that rADAM9D induces specific cellular migratory properties when compared with different constructs having additional domains, specially those of metalloproteinase and cysteine-rich domains. Furthermore, we showed that rADAM9D was able to inhibit cell adhesion, migration and invasion mainly through interacting with α6β1 in DU145 tumor cell line. These results may contribute to the development of new therapeutic strategies for prostate cancer. PMID:26211476

  7. The emerging role of matrix metalloproteases of the ADAM family in male germ cell apoptosis

    PubMed Central

    Urriola-Muñoz, Paulina; Lagos-Cabré, Raúl

    2011-01-01

    Constitutive germ cell apoptosis during mammalian spermatogenesis is a key process for controlling sperm output and to eliminate damaged or unwanted cells. An increase or decrease in the apoptosis rate has deleterious consequences and leads to low sperm production. Apoptosis in spermatogenesis has been widely studied, but the mechanism by which it is induced under physiological or pathological conditions has not been clarified. We have recently identified the metalloprotease ADAM17 (TACE) as a putative physiological inducer of germ cell apoptosis. The mechanisms involved in regulating the shedding of the ADAM17 extracellular domain are still far from being understood, although they are important in order to understand cell-cell communications. Here, we review the available data regarding apoptosis during mammalian spermatogenesis and the localization of ADAM proteins in the male reproductive tract. We propose an integrative working model where ADAM17, p38 MAPK, protein kinase C (PKC) and the tyrosine kinase c-Abl participate in the physiological signalling cascade inducing apoptosis in germ cells. In our model, we also propose a role for the Sertoli cell in regulating the Fas/FasL system in order to induce the extrinsic pathway of apoptosis in germ cells. This working model could be applied to further understand constitutive apoptosis in spermatogenesis and in pathological conditions (e.g., varicocele) or following environmental toxicants exposure (e.g., genotoxicity or xenoestrogens). PMID:22319668

  8. Disintegrin Metalloprotease (ADAM) 10 Regulates Endothelial Permeability and T Cell Transmigration by Proteolysis of Vascular Endothelial Cadherin

    PubMed Central

    Schulz, Beate; Pruessmeyer, Jessica; Maretzky, Thorsten; Ludwig, Andreas; Blobel, Carl P.; Saftig, Paul; Reiss, Karina

    2009-01-01

    Vascular endothelial (VE)-cadherin is the major adhesion molecule of endothelial adherens junctions. It plays an essential role in controlling endothelial permeability, vascular integrity, leukocyte transmigration, and angiogenesis. Elevated levels of soluble VE-cadherin are associated with diseases like coronary atherosclerosis. Previous data showed that the extracellular domain of VE-cadherin is released by an unknown metalloprotease activity during apoptosis. In this study, we used gain of function analyses, inhibitor studies and RNA interference experiments to analyze the proteolytic release of VE-cadherin in human umbilical vein endothelial cells (HUVECs). We found that VE-cadherin is specifically cleaved by the disintegrin and metalloprotease ADAM10 in its ectodomain releasing a soluble fragment and generating a carboxyterminal membrane bound stub, which is a substrate for a subsequent γ-secretase cleavage. This ADAM10-mediated proteolysis could be induced by Ca2+-influx and staurosporine treatment, indicating that ADAM10-mediated VE-cadherin cleavage contributes to the dissolution of adherens junctions during endothelial cell activation and apoptosis, respectively. In contrast, protein kinase C activation or inhibition did not modulate VE-cadherin processing. Increased ADAM10 expression was functionally associated with an increase in endothelial permeability. Remarkably, our data indicate that ADAM10 activity also contributes to the thrombin-induced decrease of endothelial cell-cell adhesion. Moreover, knockdown of ADAM10 in HUVECs as well as in T cells by small interfering RNA impaired T cell transmigration. Taken together our data identify ADAM10 as a novel regulator of vascular permeability and demonstrate a hitherto unknown function of ADAM10 in the regulation of VE-cadherin-dependent endothelial cell functions and leukocyte transendothelial migration. PMID:18420943

  9. Lysophosphatidic acid-induced ADAM12 expression mediates human adipose tissue-derived mesenchymal stem cell-stimulated tumor growth.

    PubMed

    Do, Eun Kyoung; Kim, Young Mi; Heo, Soon Chul; Kwon, Yang Woo; Shin, Sang Hun; Suh, Dong-Soo; Kim, Ki-Hyung; Yoon, Man-Soo; Kim, Jae Ho

    2012-11-01

    Lysophosphatidic acid (LPA) is involved in mesenchymal stem cell-stimulated tumor growth in vivo. However, the molecular mechanism by which mesenchymal stem cells promote tumorigenesis remains elusive. In the present study, we demonstrate that conditioned medium from A549 human lung adenocarcinoma cells (A549 CM) induced the expression of ADAM12, a disintegrin and metalloproteases family member, in human adipose tissue-derived mesenchymal stem cells (hASCs). A549 CM-stimulated ADAM12 expression was abrogated by pretreatment of hASCs with the LPA receptor 1 inhibitor Ki16425 or by small interfering RNA-mediated silencing of LPA receptor 1, suggesting a key role for the LPA-LPA receptor 1 signaling axis in A549 CM-stimulated ADAM12 expression. Silencing of ADAM12 expression using small interfering RNA or short hairpin RNA abrogated LPA-induced expression of both α-smooth muscle actin, a marker of carcinoma-associated fibroblasts, and ADAM12 in hASCs. Using a xenograft transplantation model of A549 cells, we demonstrated that silencing of ADAM12 inhibited the hASC-stimulated in vivo growth of A549 xenograft tumors and the differentiation of transplanted hASCs to α-smooth muscle actin-positive carcinoma-associated fibroblasts. LPA-conditioned medium from hASCs induced the adhesion of A549 cells and silencing of ADAM12 inhibited LPA-induced expression of extracellular matrix proteins, periostin and βig-h3, in hASCs and LPA-conditioned medium-stimulated adhesion of A549 cells. These results suggest a pivotal role for LPA-stimulated ADAM12 expression in tumor growth and the differentiation of hASCs to carcinoma-associated fibroblasts expressing α-smooth muscle actin, periostin, and βig-h3.

  10. Novel Gbeta Mimic Kelch Proteins (Gpb1 and Gpb2 Connect G-Protein Signaling to Ras via Yeast Neurofibromin Homologs Ira1 and Ira2. A Model for Human NF1

    DTIC Science & Technology

    2007-03-01

    half of Kel1 (Kelch-repeat protein 1) is homologous to S. pombe or C . neoformans Ral2. S. cerevisiae Kel1 is involved in cell morphology and mating...Based on BLAST searches, C . neoformans has genes encoding hypothetical proteins homologous to the kelch-repeat containing amino terminus of...RAL2), KEM2(KEL1), KEL2) in the C . neoformans H99 strain background and found that Kem1 (Ral2) and Kem2 (Kel1), but not Kel2, are in part involved in

  11. Targeting autocrine HB-EGF signaling with specific ADAM12 inhibition using recombinant ADAM12 prodomain

    PubMed Central

    Miller, Miles A.; Moss, Marcia L.; Powell, Gary; Petrovich, Robert; Edwards, Lori; Meyer, Aaron S.; Griffith, Linda G.; Lauffenburger, Douglas A.

    2015-01-01

    Dysregulation of ErbB-family signaling underlies numerous pathologies and has been therapeutically targeted through inhibiting ErbB-receptors themselves or their cognate ligands. For the latter, “decoy” antibodies have been developed to sequester ligands including heparin-binding epidermal growth factor (HB-EGF); however, demonstrating sufficient efficacy has been difficult. Here, we hypothesized that this strategy depends on properties such as ligand-receptor binding affinity, which varies widely across the known ErbB-family ligands. Guided by computational modeling, we found that high-affinity ligands such as HB-EGF are more difficult to target with decoy antibodies compared to low-affinity ligands such as amphiregulin (AREG). To address this issue, we developed an alternative method for inhibiting HB-EGF activity by targeting its cleavage from the cell surface. In a model of the invasive disease endometriosis, we identified A Disintegrin and Metalloproteinase 12 (ADAM12) as a protease implicated in HB-EGF shedding. We designed a specific inhibitor of ADAM12 based on its recombinant prodomain (PA12), which selectively inhibits ADAM12 but not ADAM10 or ADAM17. In endometriotic cells, PA12 significantly reduced HB-EGF shedding and resultant cellular migration. Overall, specific inhibition of ligand shedding represents a possible alternative to decoy antibodies, especially for ligands such as HB-EGF that exhibit high binding affinity and localized signaling. PMID:26477568

  12. Targeting autocrine HB-EGF signaling with specific ADAM12 inhibition using recombinant ADAM12 prodomain.

    PubMed

    Miller, Miles A; Moss, Marcia L; Powell, Gary; Petrovich, Robert; Edwards, Lori; Meyer, Aaron S; Griffith, Linda G; Lauffenburger, Douglas A

    2015-10-19

    Dysregulation of ErbB-family signaling underlies numerous pathologies and has been therapeutically targeted through inhibiting ErbB-receptors themselves or their cognate ligands. For the latter, "decoy" antibodies have been developed to sequester ligands including heparin-binding epidermal growth factor (HB-EGF); however, demonstrating sufficient efficacy has been difficult. Here, we hypothesized that this strategy depends on properties such as ligand-receptor binding affinity, which varies widely across the known ErbB-family ligands. Guided by computational modeling, we found that high-affinity ligands such as HB-EGF are more difficult to target with decoy antibodies compared to low-affinity ligands such as amphiregulin (AREG). To address this issue, we developed an alternative method for inhibiting HB-EGF activity by targeting its cleavage from the cell surface. In a model of the invasive disease endometriosis, we identified A Disintegrin and Metalloproteinase 12 (ADAM12) as a protease implicated in HB-EGF shedding. We designed a specific inhibitor of ADAM12 based on its recombinant prodomain (PA12), which selectively inhibits ADAM12 but not ADAM10 or ADAM17. In endometriotic cells, PA12 significantly reduced HB-EGF shedding and resultant cellular migration. Overall, specific inhibition of ligand shedding represents a possible alternative to decoy antibodies, especially for ligands such as HB-EGF that exhibit high binding affinity and localized signaling.

  13. Targeting autocrine HB-EGF signaling with specific ADAM12 inhibition using recombinant ADAM12 prodomain

    NASA Astrophysics Data System (ADS)

    Miller, Miles A.; Moss, Marcia L.; Powell, Gary; Petrovich, Robert; Edwards, Lori; Meyer, Aaron S.; Griffith, Linda G.; Lauffenburger, Douglas A.

    2015-10-01

    Dysregulation of ErbB-family signaling underlies numerous pathologies and has been therapeutically targeted through inhibiting ErbB-receptors themselves or their cognate ligands. For the latter, “decoy” antibodies have been developed to sequester ligands including heparin-binding epidermal growth factor (HB-EGF); however, demonstrating sufficient efficacy has been difficult. Here, we hypothesized that this strategy depends on properties such as ligand-receptor binding affinity, which varies widely across the known ErbB-family ligands. Guided by computational modeling, we found that high-affinity ligands such as HB-EGF are more difficult to target with decoy antibodies compared to low-affinity ligands such as amphiregulin (AREG). To address this issue, we developed an alternative method for inhibiting HB-EGF activity by targeting its cleavage from the cell surface. In a model of the invasive disease endometriosis, we identified A Disintegrin and Metalloproteinase 12 (ADAM12) as a protease implicated in HB-EGF shedding. We designed a specific inhibitor of ADAM12 based on its recombinant prodomain (PA12), which selectively inhibits ADAM12 but not ADAM10 or ADAM17. In endometriotic cells, PA12 significantly reduced HB-EGF shedding and resultant cellular migration. Overall, specific inhibition of ligand shedding represents a possible alternative to decoy antibodies, especially for ligands such as HB-EGF that exhibit high binding affinity and localized signaling.

  14. Iterative Mechanism Solutions with Scenario and ADAMS

    NASA Technical Reports Server (NTRS)

    Rhoades, Daren

    2006-01-01

    This slide presentation reviews the use of iterative solutions using Scenario for Motion (UG NX 2 Motion) to assist in designing the Mars Science Laboratory (MSL). The MSL will have very unique design requirements, and in order to meet these requirements the system must have the ability to design for static stability, simulate mechanism kinematics, simulate dynamic behaviour and be capable of reconfiguration, and iterations as designed. The legacy process used on the Mars Exploration rovers worked, but it was cumbersome using multiple tools, limited configuration control, with manual process and communication, and multiple steps. The aim is to develop a mechanism that would reduce turn around time, and make more reiterations possible, to improve the quality and quantity of data, and to enhance configuration control. Currently for NX Scenario for Motion uses are in the articulation studies, the simulations of traverse motions,and subsystem simulations. The design of the Rover landing model requires accurate results, flexible elements, such as beams, and the use of the full ADAMS solver has been used. In order to achieve this, when required, there has been a direct translation from Scenario to ADAMS, with additional data in ascii format. The process that has been designed to move from Scenario to ADAMS is reviewed.

  15. Catalytic properties of ADAM12 and its domain deletion mutants.

    PubMed

    Jacobsen, Jonas; Visse, Robert; Sørensen, Hans Peter; Enghild, Jan J; Brew, Keith; Wewer, Ulla M; Nagase, Hideaki

    2008-01-15

    Human ADAM12 (a disintegrin and metalloproteinase) is a multidomain zinc metalloproteinase expressed at high levels during development and in human tumors. ADAM12 exists as two splice variants: a classical type 1 membrane-anchored form (ADAM12-L) and a secreted splice variant (ADAM12-S) consisting of pro, catalytic, disintegrin, cysteine-rich, and EGF domains. Here we present a novel activity of recombinant ADAM12-S and its domain deletion mutants on S-carboxymethylated transferrin (Cm-Tf). Cleavage of Cm-Tf occurred at multiple sites, and N-terminal sequencing showed that the enzyme exhibits restricted specificity but a consensus sequence could not be defined as its subsite requirements are promiscuous. Kinetic analysis revealed that the noncatalytic C-terminal domains are important regulators of Cm-Tf activity and that ADAM12-PC consisting of the pro domain and catalytic domain is the most active on this substrate. It was also observed that NaCl inhibits ADAM12. Among the tissue inhibitors of metalloproteinases (TIMP) examined, the N-terminal domain of TIMP-3 (N-TIMP-3) inhibits ADAM12-S and ADAM12-PC with low nanomolar Ki(app) values while TIMP-2 inhibits them with a slightly lower affinity (9-44 nM). However, TIMP-1 is a much weaker inhibitor. N-TIMP-3 variants that lack MMP inhibitory activity but retained the ability to inhibit ADAM17/TACE failed to inhibit ADAM12. These results indicate unique enzymatic properties of ADAM12 among the members of the ADAM family of metalloproteinases.

  16. Batesian mimics influence mimicry ring evolution.

    PubMed

    Franks, Daniel W; Noble, Jason

    2004-01-22

    Mathematical models of mimicry typically involve artificial prey species with fixed colorations or appearances; this enables a comparison of predation rates to demonstrate the level of protection a mimic might be afforded. Fruitful theoretical results have been produced using this method, but it is also useful to examine the possible evolutionary consequences of mimicry. To that end, we present individual-based evolutionary simulation models where prey colorations are free to evolve. We use the models to examine the effect of Batesian mimics on Müllerian mimics and mimicry rings. Results show that Batesian mimics can potentially incite Müllerian mimicry relationships and encourage mimicry ring convergence.

  17. An RF Performance Sensitivity and Process Yield Model for MIMIC CAD applications. MIMIC Program. Phase 3

    DTIC Science & Technology

    1991-09-16

    AD-A242 266 --III ! I I I 1111 i~tll An RF Performance Sensitivity and Process Yield Model for MIMIC CAD Applications MIMIC Program, Phase 3 Final...DAAL01-89-K-0906-4 September 16, 1991 An RF Performance Sensitivity and Process Yield Model for MIMIC CAD Applications MIMIC Program, Phase 3 Final...Yield Model MIMIC Phase 3 for MIMIC CAD Applications Contract No. DAALO1-89-K-0906-4 6. AUTHOR(S) R.J. Trew, D.E. Stoneking, P.Gilmore, C.T. Kelley

  18. Which polyesters can mimic polyethylene?

    PubMed

    Stempfle, Florian; Ortmann, Patrick; Mecking, Stefan

    2013-01-11

    Self-metathesis of erucic acid by [(PCy(3))(η-C-C(3)H(4)N(2)Mes(2))Cl(2)Ru = CHPh] (Grubbs second- generation catalyst) followed by catalytic hydrogenation and purification via the ester yields 1,26-hexacosanedioate (>99% purity). Polyesterification with 1,26-hexacosanediol, generated from the diester, affords polyester-26,26, which features a T(m) of 114 °C (T(c) = 92 °C, ΔH(m) = 160 J g(-1)). Ultralong-chain model polyesters-38,23 (T(m) = 109 °C) and -44,23 (T(m) = 111 °C), generated via multistep procedures including acyclic diene metathesis polymerization, underline that melting points of such aliphatic polyesters do not gradually increase with methylene sequence chain length. Available data suggest that to mimic linear polyethylenes thermal properties, even longer sequences, amounting to at least four times a fatty acid chain, fully incorporated in a linear fashion are required.

  19. Novel Gbeta Mimic Kelch Proteins (Gpb1 and Gpb2 Connect G-Protein Signaling to Ras via Yeast Neurofibromin Homologs Ira1 and Ira2: A Model for Human NF1

    DTIC Science & Technology

    2008-03-01

    the level of pigmentation produced following 2 or 4 days incubation compared to the isogenic wild type strains and mutants with defects in the enzyme...coupling, Gpb1/2 serve as potent molecular brakes to constrain signaling via the PKA signaling pathway during both vegetative growth and dimorphic...In ad- dition to regulating Ras activity, neurofibromin also gov- erns G protein-mediated adenylyl cyclase activity in the fruit fly Drosophila

  20. Internal architecture of the proximal femur--Adam's or Adams' arch? Historical mystery.

    PubMed

    Bartonícek, J

    2002-12-01

    The designation 'Adam Bogen' describing the thick medial cortex of the femoral neck is an incorrect term. This arch was described by Robert Adams (1795-1871), an outstanding Irish anatomist and surgeon. He was famous mainly for his book on gout and the description of disorders of cardiac rhythm, the so-called Adams-Stokes syndrome. He published his original description in the today unfortunately almost forgotten Cyclopaedia of Anatomy and Physiology, Vol. II (London, Longman, 1836-1839). The main editor of this monumental six-volume work was the famous anatomist and surgeon R.B.Todd. This book represents a significant source of information on diseases and injuries of the great joints (shoulder, elbow, wrist, knee, ankle).

  1. Shedding of Collagen XVII/BP180 in Skin Depends on Both ADAM10 and ADAM9*

    PubMed Central

    Franzke, Claus-Werner; Bruckner-Tuderman, Leena; Blobel, Carl P.

    2009-01-01

    Collagen XVII is a transmembrane collagen and the major autoantigen of the autoimmune skin blistering disease bullous pemphigoid. Collagen XVII is proteolytically released from the membrane, and the pathogenic epitope harbors the cleavage site for its ectodomain shedding, suggesting that proteolysis has an important role in regulating the function of collagen XVII in skin homeostasis. Previous studies identified ADAMs 9, 10, and 17 as candidate collagen XVII sheddases and suggested that ADAM17 is a major sheddase. Here we show that ADAM17 only indirectly affects collagen XVII shedding and that ADAMs 9 and 10 are the most prominent collagen XVII sheddases in primary keratinocytes because (a) collagen XVII shedding was not stimulated by phorbol esters, known activators of ADAM17, (b) constitutive and calcium influx-stimulated shedding was sensitive to the ADAM10-selective inhibitor GI254023X and was strongly reduced in Adam10−/− cells, (c) there was a 55% decrease in constitutive collagen XVII ectodomain shedding from Adam9−/− keratinocytes, and (d) H2O2 enhanced ADAM9 expression and stimulated collagen XVII shedding in skin and keratinocytes of wild type mice but not of Adam9−/− mice. We conclude that ADAM9 and ADAM10 can both contribute to collagen XVII shedding in skin with an enhanced relative contribution of ADAM9 in the presence of reactive oxygen species. These results provide critical new insights into the identity and regulation of the major sheddases for collagen XVII in keratinocytes and skin and have implications for the treatment of blistering diseases of the skin. PMID:19574220

  2. Shedding of collagen XVII/BP180 in skin depends on both ADAM10 and ADAM9.

    PubMed

    Franzke, Claus-Werner; Bruckner-Tuderman, Leena; Blobel, Carl P

    2009-08-28

    Collagen XVII is a transmembrane collagen and the major autoantigen of the autoimmune skin blistering disease bullous pemphigoid. Collagen XVII is proteolytically released from the membrane, and the pathogenic epitope harbors the cleavage site for its ectodomain shedding, suggesting that proteolysis has an important role in regulating the function of collagen XVII in skin homeostasis. Previous studies identified ADAMs 9, 10, and 17 as candidate collagen XVII sheddases and suggested that ADAM17 is a major sheddase. Here we show that ADAM17 only indirectly affects collagen XVII shedding and that ADAMs 9 and 10 are the most prominent collagen XVII sheddases in primary keratinocytes because (a) collagen XVII shedding was not stimulated by phorbol esters, known activators of ADAM17, (b) constitutive and calcium influx-stimulated shedding was sensitive to the ADAM10-selective inhibitor GI254023X and was strongly reduced in Adam10(-/-) cells, (c) there was a 55% decrease in constitutive collagen XVII ectodomain shedding from Adam9(-/-) keratinocytes, and (d) H(2)O(2) enhanced ADAM9 expression and stimulated collagen XVII shedding in skin and keratinocytes of wild type mice but not of Adam9(-/-) mice. We conclude that ADAM9 and ADAM10 can both contribute to collagen XVII shedding in skin with an enhanced relative contribution of ADAM9 in the presence of reactive oxygen species. These results provide critical new insights into the identity and regulation of the major sheddases for collagen XVII in keratinocytes and skin and have implications for the treatment of blistering diseases of the skin.

  3. ADAM28 is expressed by epithelial cells in human normal tissues and protects from C1q-induced cell death.

    PubMed

    Miyamae, Yuka; Mochizuki, Satsuki; Shimoda, Masayuki; Ohara, Kentaro; Abe, Hitoshi; Yamashita, Shuji; Kazuno, Saiko; Ohtsuka, Takashi; Ochiai, Hiroki; Kitagawa, Yuko; Okada, Yasunori

    2016-05-01

    ADAM28 (disintegrin and metalloproteinase 28), which was originally reported to be lymphocyte-specific, is over-expressed by carcinoma cells and plays a key role in cell proliferation and progression in human lung and breast carcinomas. We studied ADAM28 expression in human normal tissues and examined its biological function. By using antibodies specific to ADAM28, ADAM28 was immunolocalized mainly to epithelial cells in several tissues, including epididymis, bronchus and stomach, whereas lymphocytes in lymph nodes and spleen were negligibly immunostained. RT-PCR, immunoblotting and ELISA analyses confirmed the expression in these tissues, and low or negligible expression by lymphocytes was found in the lymph node and spleen. C1q was identified as a candidate ADAM28-binding protein from a human lung cDNA library by yeast two-hybrid system, and specific binding was demonstrated by binding assays, immunoprecipitation and surface plasmon resonance. C1q treatment of normal bronchial epithelial BEAS-2B and NHBE cells, both of which showed low-level expression of ADAM28, caused apoptosis through activation of p38 and caspase-3, and cell death with autophagy through accumulation of LC3-II and autophagosomes, respectively. C1q-induced cell death was attenuated by treatment of the cells with antibodies against the C1q receptor gC1qR/p33 or cC1qR/calreticulin. Treatment of C1q with recombinant ADAM28 prior to addition to culture media reduced C1q-induced cell death, and knockdown of ADAM28 using siRNAs increased cell death. These data demonstrate that ADAM28 is expressed by epithelial cells of several normal organs, and suggest that ADAM28 plays a role in cell survival by suppression of C1q-induced cytotoxicity in bronchial epithelial cells.

  4. Once a Batesian mimic, not always a Batesian mimic: mimic reverts back to ancestral phenotype when the model is absent.

    PubMed

    Prudic, Kathleen L; Oliver, Jeffrey C

    2008-05-22

    Batesian mimics gain protection from predation through the evolution of physical similarities to a model species that possesses anti-predator defences. This protection should not be effective in the absence of the model since the predator does not identify the mimic as potentially dangerous and both the model and the mimic are highly conspicuous. Thus, Batesian mimics should probably encounter strong predation pressure outside the geographical range of the model species. There are several documented examples of Batesian mimics occurring in locations without their models, but the evolutionary responses remain largely unidentified. A mimetic species has four alternative evolutionary responses to the loss of model presence. If predation is weak, it could maintain its mimetic signal. If predation is intense, it is widely presumed the mimic will go extinct. However, the mimic could also evolve a new colour pattern to mimic another model species or it could revert back to its ancestral, less conspicuous phenotype. We used molecular phylogenetic approaches to reconstruct and test the evolution of mimicry in the North American admiral butterflies (Limenitis: Nymphalidae). We confirmed that the more cryptic white-banded form is the ancestral phenotype of North American admiral butterflies. However, one species, Limenitis arthemis, evolved the black pipevine swallowtail mimetic form but later reverted to the white-banded more cryptic ancestral form. This character reversion is strongly correlated with the geographical absence of the model species and its host plant, but not the host plant distribution of L. arthemis. Our results support the prediction that a Batesian mimic does not persist in locations without its model, but it does not go extinct either. The mimic can revert back to its ancestral, less conspicuous form and persist.

  5. Adam12 plays a role during uterine decidualization in mice.

    PubMed

    Zhang, Li; Guo, Weixiang; Chen, Qi; Fan, Xiujun; Zhang, Ying; Duan, Enkui

    2009-12-01

    In mouse, decidualization is characterized by the proliferation of stromal cells and their differentiation into specialized type of cells (decidual cells) with polyploidy, surrounding the implanting blastocyst. However, the mechanisms involved in these processes remain poorly understood. Using multiple approaches, we have examined the role of Adam12 in decidualization during early pregnancy in mice. Adam12 is spatiotemporally expressed in decidualizing stromal cells in intact pregnant females and in pseudopregnant mice undergoing artificially induced decidualization. In the ovariectomized mouse uterus, the expression of Adam12 is upregulated after progesterone treatment, which is primarily mediated by nuclear progesterone receptor. In a stromal cell culture model, the expression of Adam12 gradually rises with the progression of stromal decidualization, whereas the attenuated expression of Adam12 after siRNA knockdown significantly blocks the progression of decidualization. Our study suggests that Adam12 is involved in promoting uterine decidualization during pregnancy.

  6. Dysfunctional ADAM22 implicated in progressive encephalopathy with cortical atrophy and epilepsy

    PubMed Central

    Muona, Mikko; Fukata, Yuko; Anttonen, Anna-Kaisa; Laari, Anni; Palotie, Aarno; Pihko, Helena; Lönnqvist, Tuula; Valanne, Leena; Somer, Mirja; Fukata, Masaki

    2016-01-01

    Objective: To identify the molecular genetic basis of a syndrome characterized by rapidly progressing cerebral atrophy, intractable seizures, and intellectual disability. Methods: We performed exome sequencing in the proband and whole-genome single nucleotide polymorphism genotyping (copy number variant analysis) in the proband-parent trio. We used heterologous expression systems to study the functional consequences of identified mutations. Results: The search for potentially deleterious recessive or de novo variants yielded compound heterozygous missense (c.1202G>A, p.Cys401Tyr) and frameshift deletion (c.2396delG, p.Ser799IlefsTer96) mutations in ADAM22, which encodes a postsynaptic receptor for LGI1. The deleterious effect of the mutations was observed in cell surface binding and immunoprecipitation assays, which revealed that both mutant proteins failed to bind to LGI1. Furthermore, immunoprecipitation assays showed that the frameshift mutant ADAM22 also did not bind to the postsynaptic scaffolding protein PSD-95. Conclusions: The mutations identified abolish the LGI1-ADAM22 ligand-receptor complex and are thus a likely primary cause of the proband's epilepsy syndrome, which is characterized by unusually rapidly progressing cortical atrophy starting at 3–4 months of age. These findings are in line with the implicated role of the LGI1-ADAM22 complex as a key player in nervous system development, specifically in functional maturation of postnatal synapses. Because the frameshift mutation affects an alternatively spliced exon with highest expression in postnatal brain, the combined effect of the mutations is likely to be hypomorphic rather than complete loss of function. This is compatible with the longer survival of the patient compared to Lgi1−/− and Adam22−/− mice, which develop lethal seizures during the first postnatal weeks. PMID:27066583

  7. ADAM10 inhibition of human CD30 shedding increases specificity of targeted immunotherapy in vitro.

    PubMed

    Eichenauer, Dennis A; Simhadri, Vijaya Lakshmi; von Strandmann, Elke Pogge; Ludwig, Andreas; Matthews, Vance; Reiners, Katrin S; von Tresckow, Bastian; Saftig, Paul; Rose-John, Stefan; Engert, Andreas; Hansen, Hinrich P

    2007-01-01

    CD30 is a transmembrane protein selectively overexpressed on many human lymphoma cells and therefore an interesting target for antibody-based immunotherapy. However, binding of therapeutic antibodies stimulates a juxtamembrane cleavage of CD30 leading to a loss of target antigen and an enhanced release of the soluble ectodomain of CD30 (sCD30). Here, we show that sCD30 binds to CD30 ligand (CD153)-expressing non-target cells. Because antibodies bind to sCD30, this results in unwanted antibody binding to these cells via sCD30 bridging. To overcome shedding-dependent damage of normal cells in CD30-specific immunotherapy, we analyzed the mechanism involved in the release. Shedding of CD30 can be enhanced by protein kinase C (PKC) activation, implicating the disintegrin metalloproteinase ADAM17 but not free cytoplasmic calcium. However, antibody-induced CD30 shedding is calcium dependent and PKC independent. This shedding involved the related metalloproteinase ADAM10 as shown by the use of the preferential ADAM10 inhibitor GI254023X and by an ADAM10-deficient cell line generated from embryonically lethal ADAM10(-/-) mouse. In coculture experiments, the antibody-induced transfer of sCD30 from the human Hodgkin's lymphoma cell line L540 to the CD30-negative but CD153-expressing human mast cell line HMC-1 was inhibited by GI254023X. These findings suggest that selective metalloproteinase inhibitors blocking antibody-induced shedding of target antigens could be of therapeutic value to increase the specificity and reduce side effects of immunotherapy with monoclonal antibodies.

  8. Up-regulation of the alpha-secretase ADAM10 by retinoic acid receptors and acitretin.

    PubMed

    Tippmann, Frank; Hundt, Jana; Schneider, Anja; Endres, Kristina; Fahrenholz, Falk

    2009-06-01

    Late-onset Alzheimer's disease is often connected with nutritional misbalance, such as enhanced cholesterol intake, deficiency in polyunsaturated fatty acids, or hypovitaminosis. The alpha-secretase ADAM10 has been found to be regulated by retinoic acid, the bioreactive metabolite of vitamin A. Here we show that retinoids induce gene expression of ADAM10 and alpha-secretase activity by nonpermissive retinoid acid receptor/retinoid X receptor (RAR/RXR) heterodimers, whereby alpha- and beta-isotypes of RAR play a major role. However, ligands of other RXR binding partners, such as the vitamin D receptor, do not stimulate alpha-secretase activity. On the basis of these findings, we examined the effect of synthetic retinoids and found a strong enhancement of nonamyloidogenic processing of the amyloid precursor protein by the vitamin A analog acitretin: it stimulated ADAM10 promoter activity with an EC(50) of 1.5 microM and led to an increase of mature ADAM10 protein that resulted in a two- to three-fold increase of the ratio between alpha- and beta-secretase activity in neuroblastoma cells. The alpha-secretase stimulation by acitretin was completely inhibited by the ADAM10-specific inhibitor GI254023X. Intracerebral injection of acitretin in APP/PS1-21 transgenic mice led to a reduction of Abeta(40) and Abeta(42). The results of this study may have clinical relevance because acitretin has been approved for the treatment of psoriasis since 1997 and found generally safe for long-term use in humans.

  9. Cytoskeletal confinement of CX3CL1 limits its susceptibility to proteolytic cleavage by ADAM10

    PubMed Central

    Wong, Harikesh S.; Jaumouillé, Valentin; Heit, Bryan; Doodnauth, Sasha A.; Patel, Sajedabanu; Huang, Yi-Wei; Grinstein, Sergio; Robinson, Lisa A.

    2014-01-01

    CX3CL1 is a unique chemokine that acts both as a transmembrane endothelial adhesion molecule and, upon proteolytic cleavage, a soluble chemoattractant for circulating leukocytes. The constitutive release of soluble CX3CL1 requires the interaction of its transmembrane species with the integral membrane metalloprotease ADAM10, yet the mechanisms governing this process remain elusive. Using single-particle tracking and subdiffraction imaging, we studied how ADAM10 interacts with CX3CL1. We observed that the majority of cell surface CX3CL1 diffused within restricted confinement regions structured by the cortical actin cytoskeleton. These confinement regions sequestered CX3CL1 from ADAM10, precluding their association. Disruption of the actin cytoskeleton reduced CX3CL1 confinement and increased CX3CL1–ADAM10 interactions, promoting the release of soluble chemokine. Our results demonstrate a novel role for the cytoskeleton in limiting membrane protein proteolysis, thereby regulating both cell surface levels and the release of soluble ligand. PMID:25253723

  10. ADAM Proteases: Ligand Processing and Modulation of the Notch Pathway

    PubMed Central

    Zolkiewska, Anna

    2009-01-01

    ADAM metalloproteases play important roles in development and disease. One of the key functions of ADAMs is the proteolytic processing of Notch receptors and their ligands. ADAM-mediated cleavage of Notch represents the first step of the regulated intramembrane proteolysis of the receptor, leading to activation of the Notch pathway. Recent reports indicate that the transmembrane Notch ligands also undergo ADAM-mediated processing in cultured cells and in vivo. The proteolytic processing of Notch ligands modulates the strength and duration of Notch signals, leads to generation of soluble intracellular domains of the ligands, and may support a bi-directional signaling between cells. PMID:18344021

  11. ADAM12 and PAPP-A: Candidate regulators of trophoblast invasion and first trimester markers of healthy trophoblasts.

    PubMed

    Christians, Julian K; Beristain, Alexander G

    2016-03-03

    Proper placental development and function is crucial for a healthy pregnancy, and there has been substantial research to identify markers of placental dysfunction for the early detection of pregnancy complications. Low first-trimester levels of a disintegrin and metalloproteinase 12 (ADAM12) and pregnancy-associated plasma protein-A (PAPP-A) have been consistently associated with the subsequent development of preeclampsia and fetal growth restriction. These molecules are both metalloproteinases secreted by the placenta that cleave insulin-like growth factor binding proteins (IGFBPs), although ADAM12 also has numerous other substrates. Recent work has identified ADAM12, and particularly its shorter variant, ADAM12S, as a regulator of the migration and invasion of trophoblasts into the lining of the uterus, a critical step in normal placental development. While the mechanisms underlying this regulation are not yet clear, they may involve the liberation of heparin-binding EGF-like growth factor (HB-EGF) and/or IGFs from IGFBPs. In contrast, there has been relatively little functional work examining PAPP-A or the IGFBP substrates of ADAM12 and PAPP-A. Understanding the functions of these markers and the mechanisms underlying their association with disease could improve screening strategies and enable the development of new therapeutic interventions.

  12. From Adam Swift to Adam Smith: How the "Invisible Hand" Overcomes Middle Class Hypocrisy

    ERIC Educational Resources Information Center

    Tooley, James

    2007-01-01

    This paper challenges Richard Pring's suggestion that parents using private education may be undermining the desire for social justice and equality, using recent arguments of Adam Swift as a springboard. Swift's position on the banning of private schools, which uses a Rawlsian "veil of ignorance" argument, is explored, and it is suggested that, if…

  13. Gene-specific cell labeling using MiMIC transposons

    PubMed Central

    Gnerer, Joshua P.; Venken, Koen J. T.; Dierick, Herman A.

    2015-01-01

    Binary expression systems such as GAL4/UAS, LexA/LexAop and QF/QUAS have greatly enhanced the power of Drosophila as a model organism by allowing spatio-temporal manipulation of gene function as well as cell and neural circuit function. Tissue-specific expression of these heterologous transcription factors relies on random transposon integration near enhancers or promoters that drive the binary transcription factor embedded in the transposon. Alternatively, gene-specific promoter elements are directly fused to the binary factor within the transposon followed by random or site-specific integration. However, such insertions do not consistently recapitulate endogenous expression. We used Minos-Mediated Integration Cassette (MiMIC) transposons to convert host loci into reliable gene-specific binary effectors. MiMIC transposons allow recombinase-mediated cassette exchange to modify the transposon content. We developed novel exchange cassettes to convert coding intronic MiMIC insertions into gene-specific binary factor protein-traps. In addition, we expanded the set of binary factor exchange cassettes available for non-coding intronic MiMIC insertions. We show that binary factor conversions of different insertions in the same locus have indistinguishable expression patterns, suggesting that they reliably reflect endogenous gene expression. We show the efficacy and broad applicability of these new tools by dissecting the cellular expression patterns of the Drosophila serotonin receptor gene family. PMID:25712101

  14. Gene-specific cell labeling using MiMIC transposons.

    PubMed

    Gnerer, Joshua P; Venken, Koen J T; Dierick, Herman A

    2015-04-30

    Binary expression systems such as GAL4/UAS, LexA/LexAop and QF/QUAS have greatly enhanced the power of Drosophila as a model organism by allowing spatio-temporal manipulation of gene function as well as cell and neural circuit function. Tissue-specific expression of these heterologous transcription factors relies on random transposon integration near enhancers or promoters that drive the binary transcription factor embedded in the transposon. Alternatively, gene-specific promoter elements are directly fused to the binary factor within the transposon followed by random or site-specific integration. However, such insertions do not consistently recapitulate endogenous expression. We used Minos-Mediated Integration Cassette (MiMIC) transposons to convert host loci into reliable gene-specific binary effectors. MiMIC transposons allow recombinase-mediated cassette exchange to modify the transposon content. We developed novel exchange cassettes to convert coding intronic MiMIC insertions into gene-specific binary factor protein-traps. In addition, we expanded the set of binary factor exchange cassettes available for non-coding intronic MiMIC insertions. We show that binary factor conversions of different insertions in the same locus have indistinguishable expression patterns, suggesting that they reliably reflect endogenous gene expression. We show the efficacy and broad applicability of these new tools by dissecting the cellular expression patterns of the Drosophila serotonin receptor gene family.

  15. ADAM8 as a drug target in Pancreatic Cancer

    PubMed Central

    Schlomann, Uwe; Koller, Garrit; Conrad, Catharina; Ferdous, Taheera; Golfi, Panagiota; Garcia, Adolfo Molejon; Höfling, Sabrina; Parsons, Maddy; Costa, Patricia; Soper, Robin; Bossard, Maud; Hagemann, Thorsten; Roshani, Rozita; Sewald, Norbert; Ketchem, Randal R.; Moss, Marcia L.; Rasmussen, Fred H.; Miller, Miles A.; Lauffenburger, Douglas A.; Tuveson, David A.; Nimsky, Christopher; Bartsch, Jörg W.

    2016-01-01

    Pancreatic ductal adenocarcinoma (PDAC) has a grim prognosis with less than 5% survivors after 5 years. High expression levels of ADAM8, a metalloprotease-disintegrin, are correlated with poor clinical outcome. We show that ADAM8 expression is associated with increased migration and invasiveness of PDAC cells caused by activation of ERK 1/2 and higher MMP activities. For biological function, ADAM8 requires multimerisation and associates with β1-integrin on the cell surface. A peptidomimetic ADAM8 inhibitor, BK-1361, designed by structural modelling of the disintegrin domain, prevents ADAM8 multimerisation. In PDAC cells, BK-1361 affects ADAM8 function leading to reduced invasiveness, and less ERK 1/2 and MMP activation. BK-1361 application in mice decreased tumour burden and metastasis of implanted pancreatic tumour cells and provides improved metrics of clinical symptoms and survival in a KrasG12D-driven mouse model of PDAC. Thus, our data integrate ADAM8 in pancreatic cancer signalling and validate ADAM8 as a target for PDAC therapy. PMID:25629724

  16. The Failed Educations of John Stuart Mill and Henry Adams.

    ERIC Educational Resources Information Center

    Crossley, Robert

    1979-01-01

    Analyzes and contrasts Mill's "Autobiography" and Adams'"The Education of Henry Adams" in order to present two approaches to the nature of education and of failure. Maintains that their perspectives may serve as catalysts and cautions for contemporary theories of education and its utility and relevance. (CAM)

  17. Postnatal disruption of the disintegrin/metalloproteinase ADAM10 in brain causes epileptic seizures, learning deficits, altered spine morphology, and defective synaptic functions.

    PubMed

    Prox, Johannes; Bernreuther, Christian; Altmeppen, Hermann; Grendel, Jasper; Glatzel, Markus; D'Hooge, Rudi; Stroobants, Stijn; Ahmed, Tariq; Balschun, Detlef; Willem, Michael; Lammich, Sven; Isbrandt, Dirk; Schweizer, Michaela; Horré, Katrien; De Strooper, Bart; Saftig, Paul

    2013-08-07

    The metalloproteinase ADAM10 is of importance for Notch-dependent cortical brain development. The protease is tightly linked with α-secretase activity toward the amyloid precursor protein (APP) substrate. Increasing ADAM10 activity is suggested as a therapy to prevent the production of the neurotoxic amyloid β (Aβ) peptide in Alzheimer's disease. To investigate the function of ADAM10 in postnatal brain, we generated Adam10 conditional knock-out (A10cKO) mice using a CaMKIIα-Cre deleter strain. The lack of ADAM10 protein expression was evident in the brain cortex leading to a reduced generation of sAPPα and increased levels of sAPPβ and endogenous Aβ peptides. The A10cKO mice are characterized by weight loss and increased mortality after weaning associated with seizures. Behavioral comparison of adult mice revealed that the loss of ADAM10 in the A10cKO mice resulted in decreased neuromotor abilities and reduced learning performance, which were associated with altered in vivo network activities in the hippocampal CA1 region and impaired synaptic function. Histological and ultrastructural analysis of ADAM10-depleted brain revealed astrogliosis, microglia activation, and impaired number and altered morphology of postsynaptic spine structures. A defect in spine morphology was further supported by a reduction of the expression of NMDA receptors subunit 2A and 2B. The reduced shedding of essential postsynaptic cell adhesion proteins such as N-Cadherin, Nectin-1, and APP may explain the postsynaptic defects and the impaired learning, altered network activity, and synaptic plasticity of the A10cKO mice. Our study reveals that ADAM10 is instrumental for synaptic and neuronal network function in the adult murine brain.

  18. ADAM17 Transactivates EGFR Signaling during Embryonic Eyelid Closure

    PubMed Central

    Hassemer, Eryn L.; Endres, Bradley; Toonen, Joseph A.; Ronchetti, Adam; Dubielzig, Richard; Sidjanin, Duska J.

    2013-01-01

    Purpose. During mammalian embryonic eyelid closure ADAM17 has been proposed to play a role as a transactivator of epidermal growth factor receptor (EGFR) signaling by shedding membrane bound EGFR ligands. However, ADAM17 also sheds numerous other ligands, thus implicating ADAM17 in additional molecular pathways. The goal of this study was to experimentally establish the role of ADAM17 and determine ADAM17-mediated pathways essential for the embryonic eyelid closure. Methods. Wild-type (WT) and woe mice, carrying a hypomorphic mutation in Adam17, were evaluated using H&E and scanning electron microscopy. Expressions of ADAM17, EGFR, and the phosphorylated form EGFR-P were evaluated using immunohistochemistry. BrdU and TUNEL assays were used to evaluate cell proliferation and apoptosis, respectively. In vitro scratch assays of primary cultures were used to evaluate cell migration. Clinical and histologic analyses established if the hypermorphic EgfrDsk5 allele can rescue the woe embryonic eyelid closure. Results. woe mice exhibited a failure to develop the leading edge of the eyelid and consequently failure of the embryonic eyelid closure. Expression of ADAM17 was identified in the eyelid epithelium in the cells of the leading edge. ADAM17 is essential for epithelial cell migration, but does not play a role in proliferation and apoptosis. EGFR was expressed in both WT and woe eyelid epithelium, but the phosphorylated EGFR-P form was detected only in WT. The EgfrDsk5 allele rescued woe eyelid closure defects, but also rescued woe anterior segment defects and the absence of meibomian glands. Conclusions. We provide in vivo genetic evidence that the role of ADAM17 during embryonic eyelid closure is to transactivate EGFR signaling. PMID:23211830

  19. Helping Eve overcome ADAM: G-quadruplexes in the ADAM-15 promoter as new molecular targets for breast cancer therapeutics.

    PubMed

    Brown, Robert V; Gaerig, Vanessa C; Simmons, Taesha; Brooks, Tracy A

    2013-12-05

    ADAM-15, with known zymogen, secretase, and disintegrin activities, is a catalytically active member of the ADAM family normally expressed in early embryonic development and aberrantly expressed in various cancers, including breast, prostate and lung. ADAM-15 promotes extracellular shedding of E-cadherin, a soluble ligand for the HER2/neu receptor, leading to activation, increased motility, and proliferation. Targeted downregulation of both ADAM-15 and HER2/neu function synergistically kills breast cancer cells, but to date there are no therapeutic options for decreasing ADAM-15 function or expression. In this vein, we have examined a unique string of guanine-rich DNA within the critical core promoter of ADAM-15. This region of DNA consists of seven contiguous runs of three or more consecutive guanines, which, under superhelical stress, can relax from duplex DNA to form an intrastrand secondary G-quadruplex (G4) structure. Using biophysical and biological techniques, we have examined the G4 formation within the entire and various truncated regions of the ADAM-15 promoter, and demonstrate strong intrastrand G4 formation serving to function as a biological silencer element. Characterization of the predominant G4 species formed within the ADAM-15 promoter will allow for specific drug targeting and stabilization, and the further development of novel, targeted therapeutics.

  20. IL-13-induced proliferation of airway epithelial cells: mediation by intracellular growth factor mobilization and ADAM17

    PubMed Central

    Booth, Brian W; Sandifer, Tracy; Martin, Erika L; Martin, Linda D

    2007-01-01

    Background The pleiotrophic cytokine interleukin (IL)-13 features prominently in allergic and inflammatory diseases. In allergic asthma, IL-13 is well established as an inducer of airway inflammation and tissue remodeling. We demonstrated previously that IL-13 induces release of transforming growth factor-α (TGFα) from human bronchial epithelial cells, with proliferation of these cells mediated by the autocrine/paracrine action of this growth factor. TGFα exists as an integral membrane protein and requires proteolytic processing to its mature form, with a disintegrin and metalloproteinase (ADAM)17 responsible for this processing in a variety of tissues. Methods In this study, normal human bronchial epithelial (NHBE) cells grown in air/liquid interface (ALI) culture were used to examine the mechanisms whereby IL-13 induces release of TGFα and cellular proliferation. Inhibitors and antisense RNA were used to examine the role of ADAM17 in these processes, while IL-13-induced changes in the intracellular expression of TGFα and ADAM17 were visualized by confocal microscopy. Results IL-13 was found to induce proliferation of NHBE cells, and release of TGFα, in an ADAM17-dependent manner; however, this IL-13-induced proliferation did not appear to result solely from ADAM17 activation. Rather, IL-13 induced a change in the location of TGFα expression from intracellular to apical regions of the NHBE cells. The apical region was also found to be a site of significant ADAM17 expression, even prior to IL-13 stimulation. Conclusion Results from this study indicate that ADAM17 mediates IL-13-induced proliferation and TGFα shedding in NHBE cells. Furthermore, they provide the first example wherein a cytokine (IL-13) induces a change in the intracellular expression pattern of a growth factor, apparently inducing redistribution of intracellular stores of TGFα to the apical region of NHBE cells where expression of ADAM17 is prominent. Thus, IL-13-induced, ADAM17-mediated

  1. Adam Paulsen, a Pioneer in Auroral Research

    NASA Astrophysics Data System (ADS)

    Jørgensen, Torben S.; Rasmussen, Ole

    2006-02-01

    The 20 to 30 years following the first International Polar Year in 1882-1883 was a period of quickly advancing knowledge and understanding of auroral phenomena. This was the time when hypotheses of aurora being due to, for example, reflections of fires from the interior of the Earth or sunlight from ice particles were abandoned and replaced by the mechanism of precipitating electrons. One of the auroral researchers at that time was the Dane Adam Frederik Wivet Paulsen (1833-1907). However, when reading literature about auroral history, his ideas and work do not seem to have attracted much interest outside his own and neighboring countries. For example, in his sweeping historical account Majestic Lights: The Aurora in Science, History, and the Arts [1980], author Robert Eather only referred to Paulsen in a couple of lines.

  2. EphrinB2 Affects Apical Constriction in Xenopus Embryos and is Regulated by ADAM10 and Flotillin-1

    PubMed Central

    Ji, Yon Ju; Hwang, Yoo-Seok; Mood, Kathleen; Cho, Hee-Jun; Lee, Hyun-Shik; Winterbottom, Emily; Cousin, Hèléne; Daar, Ira O.

    2014-01-01

    The Eph/ephrin signaling pathways have a critical function in cell adhesion and repulsion, and thus play key roles in various morphogenetic events during development. Here we show that a decrease in ephrinB2 protein causes neural tube closure defects during Xenopus laevis embryogenesis. Such a decrease in ephrinB2 protein levels is observed upon the loss of flotillin-1 scaffold protein, a newly identified ephrinB2-binding partner. This dramatic decline in ephrinB2 protein levels upon the absence of flotillin-1 expression is specific, and is partly the result of an increased susceptibility to cleavage by the metalloprotease ADAM10. These findings indicate that flotillin-1 regulates ephrinB2 protein levels through ADAM10, and is required for appropriate neural tube morphogenesis in the Xenopus embryo. PMID:24662724

  3. EphrinB2 affects apical constriction in Xenopus embryos and is regulated by ADAM10 and flotillin-1

    NASA Astrophysics Data System (ADS)

    Ji, Yon Ju; Hwang, Yoo-Seok; Mood, Kathleen; Cho, Hee-Jun; Lee, Hyun-Shik; Winterbottom, Emily; Cousin, Hélène; Daar, Ira O.

    2014-03-01

    The Eph/ephrin signalling pathways have a critical function in cell adhesion and repulsion, and thus play key roles in various morphogenetic events during development. Here we show that a decrease in ephrinB2 protein causes neural tube closure defects during Xenopus laevis embryogenesis. Such a decrease in ephrinB2 protein levels is observed on the loss of flotillin-1 scaffold protein, a newly identified ephrinB2-binding partner. This dramatic decline in ephrinB2 protein levels on the absence of flotillin-1 expression is specific, and is partly the result of an increased susceptibility to cleavage by the metalloprotease ADAM10. These findings indicate that flotillin-1 regulates ephrinB2 protein levels through ADAM10, and is required for appropriate neural tube morphogenesis in the Xenopus embryo.

  4. ADAM-17: The Enzyme That Does It All

    PubMed Central

    Gooz, Monika

    2010-01-01

    This review focuses on the role of ADAM-17 in disease. Since its debut as the tumor necrosis factor converting enzyme or TACE, ADAM-17 has been reported to be an indispensible regulator of almost every cellular event from proliferation to migration. The central role of ADAM-17 in cell regulation is rooted in its diverse array of substrates: cytokines, growth factors, and their receptors as well as adhesion molecules are activated or inactivated by their cleavage with ADAM-17. It is therefore not surprising that ADAM-17 is implicated in numerous human diseases including cancer, heart disease, diabetes, rheumatoid arthritis, kidney fibrosis, Alzheimer’s disease, and is a promising target for future treatments. The specific role of ADAM-17 in the pathophysiology of these diseases is very complex and depends on the cellular context. To exploit the therapeutic potential of ADAM-17, it is important to understand how its activity is regulated and how specific organs and cells can be targeted to inactivate or activate the enzyme. PMID:20184396

  5. Control design and simulation of systems modeled using ADAMS

    NASA Technical Reports Server (NTRS)

    Sohoni, Vikram N.

    1989-01-01

    A technique for control design and simulation using the ADAMS software and a control design software package is presented. For design of control systems ADAMS generates a minimum realization linear time invariant (LTI), state space representation of multi-body models. This LTI representation can be produced in formats for input to several commercial control design packages. The user can exercise various design strategies in the control design software to arrive at a suitable compensator. The resulting closed loop model can then be simulated using ADAMS. This procedure is illustrated with two examples.

  6. microRNA-590 suppresses the tumorigenesis and invasiveness of non-small cell lung cancer cells by targeting ADAM9.

    PubMed

    Wang, Fei-Fei; Wang, Song; Xue, Wen-Hua; Cheng, Jing-Liang

    2016-12-01

    microRNAs (miRNAs), a family of small non-coding RNA molecules, are implicated in cancer growth and progression. In the present study, we examined the expression and biological roles of miR-590 in non-small cell lung cancer (NSCLC). Compared to normal lung tissues, miR-590 expression was downregulated in primary NSCLCs and, to a greater extent, in corresponding brain metastases. NSCLC cell lines with high metastatic potential had significantly (P < 0.05) lower levels of miR-590 than those with low metastatic potential. Re-expression of miR-590 suppressed NSCLC cell proliferation, colony formation, migration, and invasion in vitro and tumorigenesis in vivo. In contrast, inhibition of miR-590 enhanced the migration and invasion of NSCLC cells. Mechanistic studies revealed that a disintegrin and metalloproteinase 9 (ADAM9) was a direct target of miR-590. Delivery of miR-590 mimic was found to decrease endogenous ADAM9 expression in NSCLC cells. Enforced expression of a miRNA-resistant form of ADAM9 significantly restored the aggressive behaviors in miR-590-overexpressing NSCLC cells. Taken together, our data reveal miR-590 as a tumor suppressor in NSCLC, which is at least partially mediated through targeting of ADAM9. Restoration of miR-590 may provide a promising therapeutic strategy for NSCLC.

  7. Plasma Ang2 and ADAM17 levels are elevated during clinical malaria; Ang2 level correlates with severity and expression of EPCR-binding PfEMP1.

    PubMed

    Petersen, Jens E V; Mkumbaye, Sixbert I; Vaaben, Anna V; Manjurano, Alphaxard; Lyimo, Eric; Kavishe, Reginald A; Mwakalinga, Steven B; Mosha, Jacklin; Minja, Daniel T R; Lusingu, John P A; Theander, Thor G; Lavstsen, Thomas; Wang, Christian W

    2016-10-27

    The pathogenesis of Plasmodium falciparum malaria involves a complex interplay between parasite adhesion and inflammatory response that includes release of cytokines and activation of the endothelium with accompanying release of Angiopoitin 2 (Ang2) to the plasma. A-disintegrin and metalloproteinase 17 (ADAM17) is a protein responsible for releasing cytokines, including Tumor Necrosis Factor α (TNFα), and shedding of adhesion proteins. In this study, we show that plasma levels of ADAM17 are increased in Tanzanian children hospitalized with a malaria infection compared with asymptomatic children but similar to children hospitalized with other infectious diseases. The plasma levels of ADAM17 decreased during recovery after an acute malaria episode. Plasma levels of Ang2 were associated with markers of malaria severity and levels of var transcripts encoding P. falciparum Erythrocyte Membrane Protein 1 (PfEMP1) containing Cysteine Rich Inter Domain Region α1 (CIDRα1) domains predicted to bind Endothelial Protein C receptor (EPCR). ADAM17 levels were not associated with expression of var genes encoding different PfEMP1 types when controlling for age. These data are the first to report ADAM17 plasma levels in malaria-exposed individuals, and support the notion that parasite sequestration mediated by EPCR-binding PfEMP1 is associated with endothelial activation and pathology in severe paediatric malaria.

  8. Plasma Ang2 and ADAM17 levels are elevated during clinical malaria; Ang2 level correlates with severity and expression of EPCR-binding PfEMP1

    PubMed Central

    Petersen, Jens E. V.; Mkumbaye, Sixbert I.; Vaaben, Anna V.; Manjurano, Alphaxard; Lyimo, Eric; Kavishe, Reginald A.; Mwakalinga, Steven B.; Mosha, Jacklin; Minja, Daniel T. R.; Lusingu, John P. A.; Theander, Thor G.; Lavstsen, Thomas; Wang, Christian W.

    2016-01-01

    The pathogenesis of Plasmodium falciparum malaria involves a complex interplay between parasite adhesion and inflammatory response that includes release of cytokines and activation of the endothelium with accompanying release of Angiopoitin 2 (Ang2) to the plasma. A-disintegrin and metalloproteinase 17 (ADAM17) is a protein responsible for releasing cytokines, including Tumor Necrosis Factor α (TNFα), and shedding of adhesion proteins. In this study, we show that plasma levels of ADAM17 are increased in Tanzanian children hospitalized with a malaria infection compared with asymptomatic children but similar to children hospitalized with other infectious diseases. The plasma levels of ADAM17 decreased during recovery after an acute malaria episode. Plasma levels of Ang2 were associated with markers of malaria severity and levels of var transcripts encoding P. falciparum Erythrocyte Membrane Protein 1 (PfEMP1) containing Cysteine Rich Inter Domain Region α1 (CIDRα1) domains predicted to bind Endothelial Protein C receptor (EPCR). ADAM17 levels were not associated with expression of var genes encoding different PfEMP1 types when controlling for age. These data are the first to report ADAM17 plasma levels in malaria-exposed individuals, and support the notion that parasite sequestration mediated by EPCR-binding PfEMP1 is associated with endothelial activation and pathology in severe paediatric malaria. PMID:27784899

  9. Whole-exome sequencing identifies ADAM10 mutations as a cause of reticulate acropigmentation of Kitamura, a clinical entity distinct from Dowling-Degos disease.

    PubMed

    Kono, Michihiro; Sugiura, Kazumitsu; Suganuma, Mutsumi; Hayashi, Masahiro; Takama, Hiromichi; Suzuki, Tamio; Matsunaga, Kayoko; Tomita, Yasushi; Akiyama, Masashi

    2013-09-01

    Reticulate acropigmentation of Kitamura (RAK) is a rare genetic disorder of cutaneous pigmentation with an autosomal dominant pattern of inheritance and a high penetration rate. The characteristic skin lesions are reticulate, slightly depressed pigmented macules mainly affecting the dorsa of the hands and feet, which first appear before puberty and subsequently expand to the proximal limb and the trunk. To identify mutations that cause RAK, we performed exome sequencing of four family members in a pedigree with RAK. Fifty-three SNV/Indels were considered as candidate mutations after some condition narrowing. We confirmed the mutation status in each candidate gene of four other members in the same pedigree to find the gene that matched the mutation status and phenotype of each member. A mutation in ADAM10 encoding a zinc metalloprotease, a disintegrin and metalloprotease domain-containing protein 10 (ADAM10), was identified in the RAK family. ADAM10 is known to be involved in the ectodomain shedding of various substrates in the skin. Sanger sequencing of four additional unrelated RAK patients revealed four additional ADAM10 mutations. We identified a total of three truncating mutations, a splice site mutation and a missense mutation in ADAM10. We searched for mutations in the KRT5 gene, a causative gene for the similar pigmentation disorder Dowling-Degos disease (DDD), in all the patients and found no KRT5 mutation. These results reveal that mutations in ADAM10 are a cause of RAK and that RAK is an independent clinical entity distinct from DDD.

  10. ADAM9 Expression Is Associate with Glioma Tumor Grade and Histological Type, and Acts as a Prognostic Factor in Lower-Grade Gliomas

    PubMed Central

    Fan, Xing; Wang, Yongheng; Zhang, Chuanbao; Liu, Li; Yang, Sen; Wang, Yinyan; Liu, Xing; Qian, Zenghui; Fang, Shengyu; Qiao, Hui; Jiang, Tao

    2016-01-01

    The A disintegrin and metalloproteinase 9 (ADAM9) protein has been suggested to promote carcinoma invasion and appears to be overexpressed in various human cancers. However, its role has rarely been investigated in gliomas and, thus, in the current study we have evaluated ADAM9 expression in gliomas and examined the relevance of its expression in the prognosis of glioma patients. Clinical characteristics, RNA sequence data, and the case follow-ups were reviewed for 303 patients who had histological, confirmed gliomas. The ADAM9 expression between lower-grade glioma (LGG) and glioblastoma (GBM) patients was compared and its association with progression-free survival (PFS) and overall survival (OS) was assessed to evaluate its prognostic value. Our data suggested that GBM patients had significantly higher expression of ADAM9 in comparison to LGG patients (p < 0.001, t-test). In addition, among the LGG patients, aggressive astrocytic tumors displayed significantly higher ADAM9 expression than oligodendroglial tumors (p < 0.001, t-test). Moreover, high ADAM9 expression also correlated with poor clinical outcome (p < 0.001 and p < 0.001, log-rank test, for PFS and OS, respectively) in LGG patients. Further, multivariate analysis suggested ADAM9 expression to be an independent marker of poor survival (p = 0.002 and p = 0.003, for PFS and OS, respectively). These results suggest that ADAM9 mRNA expression is associated with tumor grade and histological type in gliomas and can serve as an independent prognostic factor, specifically in LGG patients. PMID:27571068

  11. An evolutionary recent neuroepithelial cell adhesion function of huntingtin implicates ADAM10-Ncadherin.

    PubMed

    Lo Sardo, Valentina; Zuccato, Chiara; Gaudenzi, Germano; Vitali, Barbara; Ramos, Catarina; Tartari, Marzia; Myre, Michael A; Walker, James A; Pistocchi, Anna; Conti, Luciano; Valenza, Marta; Drung, Binia; Schmidt, Boris; Gusella, James; Zeitlin, Scott; Cotelli, Franco; Cattaneo, Elena

    2012-05-01

    The Huntington's disease gene product, huntingtin, is indispensable for neural tube formation, but its role is obscure. We studied neurulation in htt-null embryonic stem cells and htt-morpholino zebrafish embryos and found a previously unknown, evolutionarily recent function for this ancient protein. We found that htt was essential for homotypic interactions between neuroepithelial cells; it permitted neurulation and rosette formation by regulating metalloprotease ADAM10 activity and Ncadherin cleavage. This function was embedded in the N terminus of htt and was phenocopied by treatment of htt knockdown zebrafish with an ADAM10 inhibitor. Notably, in htt-null cells, reversion of the rosetteless phenotype occurred only with expression of evolutionarily recent htt heterologues from deuterostome organisms. Conversely, all of the heterologues that we tested, including htt from Drosophila melanogaster and Dictyostelium discoideum, exhibited anti-apoptotic activity. Thus, anti-apoptosis may have been one of htt’s ancestral function(s), but, in deuterostomes, htt evolved to acquire a unique regulatory activity for controlling neural adhesion via ADAM10-Ncadherin, with implications for brain evolution and development.

  12. iRHOM2-dependent regulation of ADAM17 in cutaneous disease and epidermal barrier function.

    PubMed

    Brooke, Matthew A; Etheridge, Sarah L; Kaplan, Nihal; Simpson, Charlotte; O'Toole, Edel A; Ishida-Yamamoto, Akemi; Marches, Olivier; Getsios, Spiro; Kelsell, David P

    2014-08-01

    iRHOM2 is a highly conserved, catalytically inactive member of the Rhomboid family, which has recently been shown to regulate the maturation of the multi-substrate ectodomain sheddase enzyme ADAM17 (TACE) in macrophages. Dominant iRHOM2 mutations are the cause of the inherited cutaneous and oesophageal cancer-susceptibility syndrome tylosis with oesophageal cancer (TOC), suggesting a role for this protein in epithelial cells. Here, using tissues derived from TOC patients, we demonstrate that TOC-associated mutations in iRHOM2 cause an increase in the maturation and activity of ADAM17 in epidermal keratinocytes, resulting in significantly upregulated shedding of ADAM17 substrates, including EGF-family growth factors and pro-inflammatory cytokines. This activity is accompanied by increased EGFR activity, increased desmosome processing and the presence of immature epidermal desmosomes, upregulated epidermal transglutaminase activity and heightened resistance to Staphylococcal infection in TOC keratinocytes. Many of these features are consistent with the presence of a constitutive wound-healing-like phenotype in TOC epidermis, which may shed light on a novel pathway in skin repair, regeneration and inflammation.

  13. Sequence-specific interaction between the disintegrin domain of mouse ADAM 2 (fertilin beta) and murine eggs. Role of the alpha(6) integrin subunit.

    PubMed

    Bigler, D; Takahashi, Y; Chen, M S; Almeida, E A; Osbourne, L; White, J M

    2000-04-21

    Little is yet known about the biological and biochemical properties of the disintegrin-like domains of ADAM (a disintegrin and metalloprotease) proteins. Mouse ADAM 2 (mADAM 2; fertilin beta) is a sperm surface protein involved in murine fertilization. We produced recombinant proteins containing the disintegrin-like domain of mADAM 2 in both insect cells and in bacteria. The protein produced in insect cells (baculo D+C) contained a signal sequence followed by the disintegrin-like and cysteine-rich domains; it was purified from the medium of recombinant baculovirus-infected cells. A bacterial construct containing the disintegrin-like domain was produced in Escherichia coli as a glutathione S-transferase chimera. Baculo D+C, as well as the D domain of the bacterial construct (released with thrombin), bound to the microvillar surface of murine eggs. Using concentrations in the range of 1 to 5 microM, both recombinant proteins strongly inhibited sperm-egg binding and fusion; the baculovirus-produced protein exhibited a somewhat greater extent of inhibition (approximately 75 versus approximately 55% maximal inhibition). Substitution of alanine for each of the five charged residues within the disintegrin loop of mADAM 2 revealed a critical importance for the aspartic acid at position nine. Binding of both recombinant proteins to the egg was inhibited by the function blocking anti-alpha(6) monoclonal antibody, GoH3, but not by a nonfunction-blocking anti-alpha(6) monoclonal antibody. Binding was also inhibited by a peptide analogue of, and with an antibody against, the disintegrin loop of mADAM 2.

  14. MIMIC Methods for Assessing Differential Item Functioning in Polytomous Items

    ERIC Educational Resources Information Center

    Wang, Wen-Chung; Shih, Ching-Lin

    2010-01-01

    Three multiple indicators-multiple causes (MIMIC) methods, namely, the standard MIMIC method (M-ST), the MIMIC method with scale purification (M-SP), and the MIMIC method with a pure anchor (M-PA), were developed to assess differential item functioning (DIF) in polytomous items. In a series of simulations, it appeared that all three methods…

  15. Tough Ceramic Mimics Mother of Pearl

    ScienceCinema

    Ritchie, Robert

    2016-07-12

    Berkeley Lab scientists have mimicked the structure of mother of pearl to create what may well be the toughest ceramic ever produced. http://newscenter.lbl.gov/press-releases/2008/12/05/scientists-create-tough-ceramic-that-mimics-mother-of-pearl/

  16. Tough Ceramic Mimics Mother of Pearl

    SciTech Connect

    Ritchie, Robert

    2009-01-01

    Berkeley Lab scientists have mimicked the structure of mother of pearl to create what may well be the toughest ceramic ever produced. http://newscenter.lbl.gov/press-releases/2008/12/05/scientists-create-tough-ceramic-that-mimics-mother-of-pearl/

  17. ADAM17 substrate release in proximal tubule drives kidney fibrosis

    PubMed Central

    Kefaloyianni, Eirini; Muthu, Muthu Lakshmi; Kaeppler, Jakob; Sun, Xiaoming; Sabbisetti, Venkata; Chalaris, Athena; Rose-John, Stefan; Wong, Eitan; Sagi, Irit; Waikar, Sushrut S.; Rennke, Helmut; Bonventre, Joseph V.

    2016-01-01

    Kidney fibrosis following kidney injury is an unresolved health problem and causes significant morbidity and mortality worldwide. In a study into its molecular mechanism, we identified essential causative features. Acute or chronic kidney injury causes sustained elevation of a disintegrin and metalloprotease 17 (ADAM17); of its cleavage-activated proligand substrates, in particular of pro-TNFα and the EGFR ligand amphiregulin (pro-AREG); and of the substrates’ receptors. As a consequence, EGFR is persistently activated and triggers the synthesis and release of proinflammatory and profibrotic factors, resulting in macrophage/neutrophil ingress and fibrosis. ADAM17 hypomorphic mice, specific ADAM17 inhibitor–treated WT mice, or mice with inducible KO of ADAM17 in proximal tubule (Slc34a1-Cre) were significantly protected against these effects. In vitro, in proximal tubule cells, we show that AREG has unique profibrotic actions that are potentiated by TNFα-induced AREG cleavage. In vivo, in acute kidney injury (AKI) and chronic kidney disease (CKD, fibrosis) patients, soluble AREG is indeed highly upregulated in human urine, and both ADAM17 and AREG expression show strong positive correlation with fibrosis markers in related kidney biopsies. Our results indicate that targeting of the ADAM17 pathway represents a therapeutic target for human kidney fibrosis. PMID:27642633

  18. Hybrid mimics and hybrid vigor in Arabidopsis.

    PubMed

    Wang, Li; Greaves, Ian K; Groszmann, Michael; Wu, Li Min; Dennis, Elizabeth S; Peacock, W James

    2015-09-01

    F1 hybrids can outperform their parents in yield and vegetative biomass, features of hybrid vigor that form the basis of the hybrid seed industry. The yield advantage of the F1 is lost in the F2 and subsequent generations. In Arabidopsis, from F2 plants that have a F1-like phenotype, we have by recurrent selection produced pure breeding F5/F6 lines, hybrid mimics, in which the characteristics of the F1 hybrid are stabilized. These hybrid mimic lines, like the F1 hybrid, have larger leaves than the parent plant, and the leaves have increased photosynthetic cell numbers, and in some lines, increased size of cells, suggesting an increased supply of photosynthate. A comparison of the differentially expressed genes in the F1 hybrid with those of eight hybrid mimic lines identified metabolic pathways altered in both; these pathways include down-regulation of defense response pathways and altered abiotic response pathways. F6 hybrid mimic lines are mostly homozygous at each locus in the genome and yet retain the large F1-like phenotype. Many alleles in the F6 plants, when they are homozygous, have expression levels different to the level in the parent. We consider this altered expression to be a consequence of transregulation of genes from one parent by genes from the other parent. Transregulation could also arise from epigenetic modifications in the F1. The pure breeding hybrid mimics have been valuable in probing the mechanisms of hybrid vigor and may also prove to be useful hybrid vigor equivalents in agriculture.

  19. TACE (ADAM17) inhibits Schwann cell myelination.

    PubMed

    La Marca, Rosa; Cerri, Federica; Horiuchi, Keisuke; Bachi, Angela; Feltri, M Laura; Wrabetz, Lawrence; Blobel, Carl P; Quattrini, Angelo; Salzer, James L; Taveggia, Carla

    2011-06-12

    Tumor necrosis factor-α-converting enzyme (TACE; also known as ADAM17) is a proteolytic sheddase that is responsible for the cleavage of several membrane-bound molecules. We report that TACE cleaves neuregulin-1 (NRG1) type III in the epidermal growth factor domain, probably inactivating it (as assessed by deficient activation of the phosphatidylinositol-3-OH kinase pathway), and thereby negatively regulating peripheral nervous system (PNS) myelination. Lentivirus-mediated knockdown of TACE in vitro in dorsal root ganglia neurons accelerates the onset of myelination and results in hypermyelination. In agreement, motor neurons of conditional knockout mice lacking TACE specifically in these cells are significantly hypermyelinated, and small-caliber fibers are aberrantly myelinated. Further, reduced TACE activity rescues hypomyelination in NRG1 type III haploinsufficient mice in vivo. We also show that the inhibitory effect of TACE is neuron-autonomous, as Schwann cells lacking TACE elaborate myelin of normal thickness. Thus, TACE is a modulator of NRG1 type III activity and is a negative regulator of myelination in the PNS.

  20. Adam Politzer-Father of Modern Otology.

    PubMed

    Dhungat, J V Pai; Gore, Geeta

    2015-09-01

    Adam Politzer (1835-1920) was born in Alberti near the city of Budapest in Hungary. He studied medicine at the University of Vienna and obtained his Doctorate degree in 1859. Some of his teachers belonged to the famous second "Vienna School" such as Joseph Skoda, Karl Rokitansky, Von Hebra, Josef Hyrtil, Johann Von Oppolzer and famous physiologist Carl Ludwig -who took special interest in him and was influential in his subsequent career. Politzer showed unusual interest in diseases of the ear and started to work in Carl Ludwig's laboratory. His interest at that time was mainly the physics of the auditory system. He studied the innervations of the intrinsic muscles of the ear There he was the first to demonstrate that the innervations of the tensor tympani muscle was by trigeminal nerve and that of the stapedial muscle was by facial nerve. He studied the air movement in the Eustachian tube and variation of air pressure in the tympanic cavity by connecting two manometers- one placed in the external auditory canal meatus, and another in the pharynx. He showed valve near the opening into the middle ear which controls the process. It is usually closed to keep the bacteria and other things away from the mouth and nose.

  1. A bivariate genome-wide association study identifies ADAM12 as a novel susceptibility gene for Kashin-Beck disease

    PubMed Central

    Hao, Jingcan; Wang, Wenyu; Wen, Yan; Xiao, Xiao; He, Awen; Guo, Xiong; Yang, Tielin; Liu, Xiaogang; Shen, Hui; Chen, Xiangding; Tian, Qing; Deng, Hong-Wen; Zhang, Feng

    2016-01-01

    Kashin-Beck disease (KBD) is a chronic osteoarthropathy, which manifests as joint deformities and growth retardation. Only a few genetic studies of growth retardation associated with the KBD have been carried out by now. In this study, we conducted a two-stage bivariate genome-wide association study (BGWAS) of the KBD using joint deformities and body height as study phenotypes, totally involving 2,417 study subjects. Articular cartilage specimens from 8 subjects were collected for immunohistochemistry. In the BGWAS, ADAM12 gene achieved the most significant association (rs1278300 p-value = 9.25 × 10−9) with the KBD. Replication study observed significant association signal at rs1278300 (p-value = 0.007) and rs1710287 (p-value = 0.002) of ADAM12 after Bonferroni correction. Immunohistochemistry revealed significantly decreased expression level of ADAM12 protein in the KBD articular cartilage (average positive chondrocyte rate = 47.59 ± 7.79%) compared to healthy articular cartilage (average positive chondrocyte rate = 64.73 ± 5.05%). Our results suggest that ADAM12 gene is a novel susceptibility gene underlying both joint destruction and growth retardation of the KBD. PMID:27545300

  2. A bivariate genome-wide association study identifies ADAM12 as a novel susceptibility gene for Kashin-Beck disease.

    PubMed

    Hao, Jingcan; Wang, Wenyu; Wen, Yan; Xiao, Xiao; He, Awen; Guo, Xiong; Yang, Tielin; Liu, Xiaogang; Shen, Hui; Chen, Xiangding; Tian, Qing; Deng, Hong-Wen; Zhang, Feng

    2016-08-22

    Kashin-Beck disease (KBD) is a chronic osteoarthropathy, which manifests as joint deformities and growth retardation. Only a few genetic studies of growth retardation associated with the KBD have been carried out by now. In this study, we conducted a two-stage bivariate genome-wide association study (BGWAS) of the KBD using joint deformities and body height as study phenotypes, totally involving 2,417 study subjects. Articular cartilage specimens from 8 subjects were collected for immunohistochemistry. In the BGWAS, ADAM12 gene achieved the most significant association (rs1278300 p-value = 9.25 × 10(-9)) with the KBD. Replication study observed significant association signal at rs1278300 (p-value = 0.007) and rs1710287 (p-value = 0.002) of ADAM12 after Bonferroni correction. Immunohistochemistry revealed significantly decreased expression level of ADAM12 protein in the KBD articular cartilage (average positive chondrocyte rate = 47.59 ± 7.79%) compared to healthy articular cartilage (average positive chondrocyte rate = 64.73 ± 5.05%). Our results suggest that ADAM12 gene is a novel susceptibility gene underlying both joint destruction and growth retardation of the KBD.

  3. Taking Charge: Walter Sydney Adams and the Mount Wilson Observatory

    NASA Astrophysics Data System (ADS)

    Brashear, R.

    2004-12-01

    The growing preeminence of American observational astronomy in the first half of the 20th century is a well-known story and much credit is given to George Ellery Hale and his skill as an observatory-building entrepreneur. But a key figure who has yet to be discussed in great detail is Walter Sydney Adams (1876-1956), Hale's Assistant Director at Mount Wilson Observatory. Due to Hale's illnesses, Adams was Acting Director for much of Hale's tenure, and he became the second Director of Mount Wilson from 1923 to 1946. Behind his New England reserve Adams was instrumental in the growth of Mount Wilson and thus American astronomy in general. Adams was hand-picked by Hale to take charge of stellar spectroscopy work at Yerkes and Mount Wilson and the younger astronomer showed tremendous loyalty to Hale and Hale's vision throughout his career. As Adams assumed the leadership role at Mount Wilson he concentrated on making the observatory a place where researchers worked with great freedom but maintain a high level of cooperation. This paper will concentrate on Adams's early years and look at his growing relationship with Hale and how he came to be the central figure in the early history of Mount Wilson as both a solar and stellar observatory. His education, his years at Dartmouth and Yerkes (including his unfortunate encounter with epsilon Leonis), and his formative years on Mount Wilson are all important in learning how he shaped the direction of Mount Wilson and the development of American astronomy in the first half of the 20th century. This latter history cannot be complete until we bring Adams into better focus.

  4. Single-Walled Carbon Nanotubes: Mimics of Biological Ion Channels

    PubMed Central

    2017-01-01

    Here we report on the ion conductance through individual, small diameter single-walled carbon nanotubes. We find that they are mimics of ion channels found in natural systems. We explore the factors governing the ion selectivity and permeation through single-walled carbon nanotubes by considering an electrostatic mechanism built around a simplified version of the Gouy–Chapman theory. We find that the single-walled carbon nanotubes preferentially transported cations and that the cation permeability is size-dependent. The ionic conductance increases as the absolute hydration enthalpy decreases for monovalent cations with similar solid-state radii, hydrated radii, and bulk mobility. Charge screening experiments using either the addition of cationic or anionic polymers, divalent metal cations, or changes in pH reveal the enormous impact of the negatively charged carboxylates at the entrance of the single-walled carbon nanotubes. These observations were modeled in the low-to-medium concentration range (0.1–2.0 M) by an electrostatic mechanism that mimics the behavior observed in many biological ion channel-forming proteins. Moreover, multi-ion conduction in the high concentration range (>2.0 M) further reinforces the similarity between single-walled carbon nanotubes and protein ion channels. PMID:28103039

  5. Single-Walled Carbon Nanotubes: Mimics of Biological Ion Channels.

    PubMed

    Amiri, Hasti; Shepard, Kenneth L; Nuckolls, Colin; Hernández Sánchez, Raúl

    2017-02-08

    Here we report on the ion conductance through individual, small diameter single-walled carbon nanotubes. We find that they are mimics of ion channels found in natural systems. We explore the factors governing the ion selectivity and permeation through single-walled carbon nanotubes by considering an electrostatic mechanism built around a simplified version of the Gouy-Chapman theory. We find that the single-walled carbon nanotubes preferentially transported cations and that the cation permeability is size-dependent. The ionic conductance increases as the absolute hydration enthalpy decreases for monovalent cations with similar solid-state radii, hydrated radii, and bulk mobility. Charge screening experiments using either the addition of cationic or anionic polymers, divalent metal cations, or changes in pH reveal the enormous impact of the negatively charged carboxylates at the entrance of the single-walled carbon nanotubes. These observations were modeled in the low-to-medium concentration range (0.1-2.0 M) by an electrostatic mechanism that mimics the behavior observed in many biological ion channel-forming proteins. Moreover, multi-ion conduction in the high concentration range (>2.0 M) further reinforces the similarity between single-walled carbon nanotubes and protein ion channels.

  6. Mimics and chameleons in motor neurone disease.

    PubMed

    Turner, Martin R; Talbot, Kevin

    2013-06-01

    The progression of motor neurone disease (MND) is currently irreversible, and the grave implications of diagnosis naturally fuels concern among neurologists over missing a potential mimic disorder. There is no diagnostic test for MND but in reality there are few plausible mimics in routine clinical practice. In the presence of a progressive pure motor disorder, signs such as florid fasciculations, bilateral tongue wasting, the 'split hand', head drop, emotionality, and cognitive or behavioural impairment carry high positive predictive value. MND is clinically heterogeneous, however, with some important chameleon-like presentations and considerable variation in clinical course. Lack of confidence about the scope of such variation, or an approach to diagnosis emphasising investigations over clinical common sense, has the potential to exacerbate diagnostic delay in MND and impede timely planning of the care which is essential to maximising quality of life.

  7. Mimics and chameleons in motor neurone disease

    PubMed Central

    Turner, Martin R; Talbot, Kevin

    2013-01-01

    The progression of motor neurone disease (MND) is currently irreversible, and the grave implications of diagnosis naturally fuels concern among neurologists over missing a potential mimic disorder. There is no diagnostic test for MND but in reality there are few plausible mimics in routine clinical practice. In the presence of a progressive pure motor disorder, signs such as florid fasciculations, bilateral tongue wasting, the ‘split hand’, head drop, emotionality, and cognitive or behavioural impairment carry high positive predictive value. MND is clinically heterogeneous, however, with some important chameleon-like presentations and considerable variation in clinical course. Lack of confidence about the scope of such variation, or an approach to diagnosis emphasising investigations over clinical common sense, has the potential to exacerbate diagnostic delay in MND and impede timely planning of the care which is essential to maximising quality of life. PMID:23616620

  8. Reproducing Natural Spider Silks' Copolymer Behavior in Synthetic Silk Mimics

    SciTech Connect

    An, Bo; Jenkins, Janelle E; Sampath, Sujatha; Holland, Gregory P; Hinman, Mike; Yarger, Jeffery L; Lewis, Randolph

    2012-10-30

    Dragline silk from orb-weaving spiders is a copolymer of two large proteins, major ampullate spidroin 1 (MaSp1) and 2 (MaSp2). The ratio of these proteins is known to have a large variation across different species of orb-weaving spiders. NMR results from gland material of two different species of spiders, N. clavipes and A. aurantia, indicates that MaSp1 proteins are more easily formed into β-sheet nanostructures, while MaSp2 proteins form random coil and helical structures. To test if this behavior of natural silk proteins could be reproduced by recombinantly produced spider silk mimic protein, recombinant MaSp1/MaSp2 mixed fibers as well as chimeric silk fibers from MaSp1 and MaSp2 sequences in a single protein were produced based on the variable ratio and conserved motifs of MaSp1 and MaSp2 in native silk fiber. Mechanical properties, solid-state NMR, and XRD results of tested synthetic fibers indicate the differing roles of MaSp1 and MaSp2 in the fiber and verify the importance of postspin stretching treatment in helping the fiber to form the proper spatial structure.

  9. Reproducing Natural Spider Silks’ Copolymer Behavior in Synthetic Silk Mimics

    PubMed Central

    An, Bo; Jenkins, Janelle E.; Sampath, Sujatha; Holland, Gregory P.; Hinman, Mike; Yarger, Jeffery L.; Lewis, Randolph

    2012-01-01

    Dragline silk from orb-weaving spiders is a copolymer of two large proteins, major ampullate spidroin 1 (MaSp1) and 2 (MaSp2). The ratio of these proteins is known to have a large variation across different species of orb-weaving spiders. NMR results from gland material of two different species of spiders, N. clavipes and A. aurantia, indicates that MaSp1 proteins are more easily formed into β-sheet nanostructures, while MaSp2 proteins form random coil and helical structures. To test if this behavior of natural silk proteins could be reproduced by recombinantly produced spider silk mimic protein, recombinant MaSp1/MaSp2 mixed fibers as well as chimeric silk fibers from MaSp1 and MaSp2 sequences in a single protein were produced based on the variable ratio and conserved motifs of MaSp1 and MaSp2 in native silk fiber. Mechanical properties, solid-state NMR, and XRD results of tested synthetic fibers indicate the differing roles of MaSp1 and MaSp2 in the fiber and verify the importance of postspin stretching treatment in helping the fiber to form the proper spatial structure. PMID:23110450

  10. Reliability evaluation of I-123 ADAM SPECT imaging using SPM software and AAL ROI methods

    NASA Astrophysics Data System (ADS)

    Yang, Bang-Hung; Tsai, Sung-Yi; Wang, Shyh-Jen; Su, Tung-Ping; Chou, Yuan-Hwa; Chen, Chia-Chieh; Chen, Jyh-Cheng

    2011-08-01

    The level of serotonin was regulated by serotonin transporter (SERT), which is a decisive protein in regulation of serotonin neurotransmission system. Many psychiatric disorders and therapies were also related to concentration of cerebral serotonin. I-123 ADAM was the novel radiopharmaceutical to image SERT in brain. The aim of this study was to measure reliability of SERT densities of healthy volunteers by automated anatomical labeling (AAL) method. Furthermore, we also used statistic parametric mapping (SPM) on a voxel by voxel analysis to find difference of cortex between test and retest of I-123 ADAM single photon emission computed tomography (SPECT) images.Twenty-one healthy volunteers were scanned twice with SPECT at 4 h after intravenous administration of 185 MBq of 123I-ADAM. The image matrix size was 128×128 and pixel size was 3.9 mm. All images were obtained through filtered back-projection (FBP) reconstruction algorithm. Region of interest (ROI) definition was performed based on the AAL brain template in PMOD version 2.95 software package. ROI demarcations were placed on midbrain, pons, striatum, and cerebellum. All images were spatially normalized to the SPECT MNI (Montreal Neurological Institute) templates supplied with SPM2. And each image was transformed into standard stereotactic space, which was matched to the Talairach and Tournoux atlas. Then differences across scans were statistically estimated on a voxel by voxel analysis using paired t-test (population main effect: 2 cond's, 1 scan/cond.), which was applied to compare concentration of SERT between the test and retest cerebral scans.The average of specific uptake ratio (SUR: target/cerebellum-1) of 123I-ADAM binding to SERT in midbrain was 1.78±0.27, pons was 1.21±0.53, and striatum was 0.79±0.13. The cronbach's α of intra-class correlation coefficient (ICC) was 0.92. Besides, there was also no significant statistical finding in cerebral area using SPM2 analysis. This finding might help us

  11. Cupric Yersiniabactin Is a Virulence-Associated Superoxide Dismutase Mimic

    PubMed Central

    2013-01-01

    Many Gram-negative bacteria interact with extracellular metal ions by expressing one or more siderophore types. Among these, the virulence-associated siderophore yersiniabactin (Ybt) is an avid copper chelator, forming stable cupric (Cu(II)-Ybt) complexes that are detectable in infected patients. Here we show that Ybt-expressing E. coli are protected from intracellular killing within copper-replete phagocytic cells. This survival advantage is highly dependent upon the phagocyte respiratory burst, during which superoxide is generated by the NADPH oxidase complex. Chemical fractionation links this phenotype to a previously unappreciated superoxide dismutase (SOD)-like activity of Cu(II)-Ybt. Unlike previously described synthetic copper-salicylate (Cu(II)-SA) SOD mimics, the salicylate-based natural product Cu(II)-Ybt retains catalytic activity at physiologically plausible protein concentrations. These results reveal a new virulence-associated adaptation based upon spontaneous assembly of a non-protein catalyst. PMID:24283977

  12. Phosphatidylserine exposure is required for ADAM17 sheddase function

    PubMed Central

    Sommer, Anselm; Kordowski, Felix; Büch, Joscha; Maretzky, Thorsten; Evers, Astrid; Andrä, Jörg; Düsterhöft, Stefan; Michalek, Matthias; Lorenzen, Inken; Somasundaram, Prasath; Tholey, Andreas; Sönnichsen, Frank D.; Kunzelmann, Karl; Heinbockel, Lena; Nehls, Christian; Gutsmann, Thomas; Grötzinger, Joachim; Bhakdi, Sucharit; Reiss, Karina

    2016-01-01

    ADAM17, a prominent member of the ‘Disintegrin and Metalloproteinase' (ADAM) family, controls vital cellular functions through cleavage of transmembrane substrates. Here we present evidence that surface exposure of phosphatidylserine (PS) is pivotal for ADAM17 to exert sheddase activity. PS exposure is tightly coupled to substrate shedding provoked by diverse ADAM17 activators. PS dependency is demonstrated in the following: (a) in Raji cells undergoing apoptosis; (b) in mutant PSA-3 cells with manipulatable PS content; and (c) in Scott syndrome lymphocytes genetically defunct in their capacity to externalize PS in response to intracellular Ca2+ elevation. Soluble phosphorylserine but not phosphorylcholine inhibits substrate cleavage. The isolated membrane proximal domain (MPD) of ADAM17 binds to PS but not to phosphatidylcholine liposomes. A cationic PS-binding motif is identified in this domain, replacement of which abrogates liposome-binding and renders the protease incapable of cleaving its substrates in cells. We speculate that surface-exposed PS directs the protease to its targets where it then executes its shedding function. PMID:27161080

  13. ADAM12: a genetic modifier of preclinical peripheral arterial disease

    PubMed Central

    Chen, Lingdan; Okutsu, Mitsuharu; Farber, Charles R.; Hazarika, Surovi; Jones, W. Schuyler; Craig, Damian; Marchuk, Douglas A.; Lye, R. John; Shah, Svati H.; Annex, Brian H.

    2015-01-01

    In prior studies from multiple groups, outcomes following experimental peripheral arterial disease (PAD) differed considerably across inbred mouse strains. Similarly, in humans with PAD, disease outcomes differ, even when there are similarities in risk factors, disease anatomy, arteriosclerotic burden, and hemodynamic measures. Previously, we identified a locus on mouse chromosome 7, limb salvage-associated quantitative trait locus 1 (LSq-1), which was sufficient to modify outcomes following experimental PAD. We compared expression of genes within LSq-1 in Balb/c mice, which normally show poor outcomes following experimental PAD, with that in C57Bl/6 mice, which normally show favorable outcomes, and found that a disintegrin and metalloproteinase gene 12 (ADAM12) had the most differential expression. Augmentation of ADAM12 expression in vivo improved outcomes following experimental PAD in Balb/c mice, whereas knockdown of ADAM12 made outcomes worse in C57Bl/6 mice. In vitro, ADAM12 expression modulates endothelial cell proliferation, survival, and angiogenesis in ischemia, and this appeared to be dependent on tyrosine kinase with Ig-like and EGF-like domain 2 (Tie2) activation. ADAM12 is sufficient to modify PAD severity in mice, and this likely occurs through regulation of Tie2. PMID:26163448

  14. Essential Role for ADAM19 in Cardiovascular Morphogenesis

    PubMed Central

    Zhou, Hong-Ming; Weskamp, Gisela; Chesneau, Valérie; Sahin, Umut; Vortkamp, Andrea; Horiuchi, Keisuke; Chiusaroli, Riccardo; Hahn, Rebecca; Wilkes, David; Fisher, Peter; Baron, Roland; Manova, Katia; Basson, Craig T.; Hempstead, Barbara; Blobel, Carl P.

    2004-01-01

    Congenital heart disease is the most common form of human birth defects, yet much remains to be learned about its underlying causes. Here we report that mice lacking functional ADAM19 (mnemonic for a disintegrin and metalloprotease 19) exhibit severe defects in cardiac morphogenesis, including a ventricular septal defect (VSD), abnormal formation of the aortic and pulmonic valves, leading to valvular stenosis, and abnormalities of the cardiac vasculature. During mouse development, ADAM19 is highly expressed in the conotruncus and the endocardial cushion, structures that give rise to the affected heart valves and the membranous ventricular septum. ADAM19 is also highly expressed in osteoblast-like cells in the bone, yet it does not appear to be essential for bone growth and skeletal development. Most adam19−/− animals die perinatally, likely as a result of their cardiac defects. These findings raise the possibility that mutations in ADAM19 may contribute to human congenital heart valve and septal defects. PMID:14673146

  15. ADAM12: a genetic modifier of preclinical peripheral arterial disease.

    PubMed

    Dokun, Ayotunde O; Chen, Lingdan; Okutsu, Mitsuharu; Farber, Charles R; Hazarika, Surovi; Jones, W Schuyler; Craig, Damian; Marchuk, Douglas A; Lye, R John; Shah, Svati H; Annex, Brian H

    2015-09-01

    In prior studies from multiple groups, outcomes following experimental peripheral arterial disease (PAD) differed considerably across inbred mouse strains. Similarly, in humans with PAD, disease outcomes differ, even when there are similarities in risk factors, disease anatomy, arteriosclerotic burden, and hemodynamic measures. Previously, we identified a locus on mouse chromosome 7, limb salvage-associated quantitative trait locus 1 (LSq-1), which was sufficient to modify outcomes following experimental PAD. We compared expression of genes within LSq-1 in Balb/c mice, which normally show poor outcomes following experimental PAD, with that in C57Bl/6 mice, which normally show favorable outcomes, and found that a disintegrin and metalloproteinase gene 12 (ADAM12) had the most differential expression. Augmentation of ADAM12 expression in vivo improved outcomes following experimental PAD in Balb/c mice, whereas knockdown of ADAM12 made outcomes worse in C57Bl/6 mice. In vitro, ADAM12 expression modulates endothelial cell proliferation, survival, and angiogenesis in ischemia, and this appeared to be dependent on tyrosine kinase with Ig-like and EGF-like domain 2 (Tie2) activation. ADAM12 is sufficient to modify PAD severity in mice, and this likely occurs through regulation of Tie2.

  16. In vitro glutathione peroxidase mimicry of ebselen is linked to its oxidation of critical thiols on key cerebral suphydryl proteins - A novel component of its GPx-mimic antioxidant mechanism emerging from its thiol-modulated toxicology and pharmacology.

    PubMed

    Kade, I J; Balogun, B D; Rocha, J B T

    2013-10-25

    The antioxidant mechanism of ebselen in rats brain is largely linked with its glutathione peroxidase (GPx) rather than its peroxiredoxin mimicry ability. However, the precise molecular dynamics between the GPx-mimicry of ebselen and thiol utilization is yet to be fully clarified and thus still open. Herein, we investigated the influence of dithiothreitol (DTT) on the antioxidant action of ebselen against oxidant-induced cerebral lipid peroxidation and deoxyribose degradation. Furthermore, the critical inhibitory concentrations of ebselen on the activities of sulphydryl enzymes such as cerebral sodium pump, δ-aminolevulinic acid dehydratase (δ-ALAD) and lactate dehydrogenase (LDH) were also investigated. We observe that ebselen (at ≥42 μM) markedly inhibited lipid peroxidation in the presence and absence of DTT, whereas it inhibited deoxyribose degradation only in the presence of DTT. Furthermore, under in vitro conditions, ebselen inhibited the thiol containing enzymes; cerebral sodium pump (at ≥40 μM), δ-ALAD (≥10 μM) and LDH (≥1 μM) which were either prevented or reversed by DTT. However, the inhibition of the activities of these sulphydryl proteins in diabetic animals was prevented by ebselen. Summarily, it is apparent that the effective in vitro inhibitory doses of ebselen on the activity of the sulphydryl proteins are far less than its antioxidant doses. In addition, the presence of DTT is evidently a critical requirement for ebselen to effect its antioxidant action against deoxyribose degeradation and not lipid peroxidation. Consequently, we conclude that ebselen possibly utilizes available thiols on sulphydryl proteins to effect its GPx mimicry antioxidant action against lipid peroxidation in rat brain homogenate.

  17. The Adam language: Ada extended with support for multiway activities

    NASA Technical Reports Server (NTRS)

    Charlesworth, Arthur

    1993-01-01

    The Adam language is an extension of Ada that supports multiway activities, which are cooperative activities involving two or more processes. This support is provided by three new constructs: diva procedures, meet statements, and multiway accept statements. Diva procedures are recursive generic procedures having a particular restrictive syntax that facilitates translation for parallel computers. Meet statements and multiway accept statements provide two ways to express a multiway rendezvous, which is an n-way rendezvous generalizing Ada's 2-way rendezvous. While meet statements tend to have simpler rules than multiway accept statements, the latter approach is a more straightforward extension of Ada. The only nonnull statements permitted within meet statements and multiway accept statements are calls on instantiated diva procedures. A call on an instantiated diva procedure is also permitted outside a multiway rendezvous; thus sequential Adam programs using diva procedures can be written. Adam programs are translated into Ada programs appropriate for use on parallel computers.

  18. ADAM12 and ADAM17 are essential molecules for hypoxia-induced impairment of neural vascular barrier function

    PubMed Central

    Cui, Dan; Arima, Mitsuru; Takubo, Keiyo; Kimura, Tokuhiro; Horiuchi, Keisuke; Minagawa, Takuya; Matsuda, Satoshi; Ikeda, Eiji

    2015-01-01

    Neural vascular barrier is essential for the life of multicellular organisms, and its impairment by tissue hypoxia is known to be a central of pathophysiology accelerating the progression of various intractable neural diseases. Therefore, the molecules involved in hypoxia-induced impairment of vascular barrier can be the targets to establish new therapies for intractable diseases. Here, we demonstrate that a disintegrin and metalloproteinases (ADAMs) 12 and 17 expressed in endothelial cells are the molecules responsible for the impairment of neural vascular barrier by hypoxia. Brain microvascular endothelial cells in vitro lost their barrier properties immediately after hypoxic stimulation through diminished localization of claudin-5, a tight junction molecule, on cell membranes. Hypoxic disappearance of claudin-5 from cell membranes and the consequent loss of barrier properties were completely suppressed by inhibition of the metalloproteinase activity which was found to be attributed to ADAM12 and ADAM17. Inhibition of either ADAM12 or ADAM17 was sufficient to rescue the in vivo neural vasculature under hypoxia from the loss of barrier function. This is the first report to specify the molecules which are responsible for hypoxia-induced impairment of neural vascular barrier and furthermore can be the targets of new therapeutic strategies for intractable neural diseases. PMID:26242473

  19. ADAM12 and ADAM17 are essential molecules for hypoxia-induced impairment of neural vascular barrier function.

    PubMed

    Cui, Dan; Arima, Mitsuru; Takubo, Keiyo; Kimura, Tokuhiro; Horiuchi, Keisuke; Minagawa, Takuya; Matsuda, Satoshi; Ikeda, Eiji

    2015-08-05

    Neural vascular barrier is essential for the life of multicellular organisms, and its impairment by tissue hypoxia is known to be a central of pathophysiology accelerating the progression of various intractable neural diseases. Therefore, the molecules involved in hypoxia-induced impairment of vascular barrier can be the targets to establish new therapies for intractable diseases. Here, we demonstrate that a disintegrin and metalloproteinases (ADAMs) 12 and 17 expressed in endothelial cells are the molecules responsible for the impairment of neural vascular barrier by hypoxia. Brain microvascular endothelial cells in vitro lost their barrier properties immediately after hypoxic stimulation through diminished localization of claudin-5, a tight junction molecule, on cell membranes. Hypoxic disappearance of claudin-5 from cell membranes and the consequent loss of barrier properties were completely suppressed by inhibition of the metalloproteinase activity which was found to be attributed to ADAM12 and ADAM17. Inhibition of either ADAM12 or ADAM17 was sufficient to rescue the in vivo neural vasculature under hypoxia from the loss of barrier function. This is the first report to specify the molecules which are responsible for hypoxia-induced impairment of neural vascular barrier and furthermore can be the targets of new therapeutic strategies for intractable neural diseases.

  20. Jefferson and Adams on the mind-body problem.

    PubMed

    Robinson, Daniel N

    2003-08-01

    Amidst the voluminous correspondence between Thomas Jefferson and John Adams are several letters pertaining to the material basis of mental life. These reveal in a most suggestive way the substantial differences between them. Well informed on prevailing scientific and philosophical perspectives, Jefferson and Adams used the issue to express their positions on the nature and limits of knowledge, the relative authority of scientific methods and speculations, and the larger question of human perfectibility. At the same time, their exchanges illuminate the prevailing and divergent perspectives on human psychology adopted by major leaders of thought in the New World.

  1. Segmental arterial mediolysis mimics systemic vasculitis.

    PubMed

    Kalfa, Melike; Kocanaoğulları, Hayriye; Karabulut, Gonca; Emmungil, Hakan; Çınar, Celal; Yılmaz, Zevcet; Gücenmez, Sercan; Kabasakal, Yasemin

    2016-09-01

    Segmental arterial mediolysis (SAM) is a rare, nonarteriosclerotic, noninflammatory vascular disease and mostly affects medium-to-large sized abdominal arteries as well as presents with hemorrhages in the abdominal cavity. We report the case of a patient with SAM of the celiac, right renal, jejunal branch of the superior mesenteric, left gastric, and splenic arteries who was diagnosed by excluding other causes and in whom transcatheter embolization was performed in two different sessions, but he died because of an undefined reason. SAM mimics systemic vasculitis and causes abdominal pain; it should be considered because abdominal hemorrhage or arterial infarction can result in death.

  2. Clickable glycopeptoids for synthesis of glycopeptide mimic.

    PubMed

    Singhamahapatra, Anadi; Sahoo, Laxminarayan; Loganathan, Duraikkannu

    2013-10-18

    Structurally diverse novel glycopeptoids were synthesized which can be attached to biologically important peptides by click reaction to improve their potential to be used in medicinal chemistry. Triazole-linked αβ-hydrid glycopeptoids were synthesized that mimic the conserved linkage region of N-linked glycoproteins in eukaryotes. The amide bonds were replaced with triazole rings, and αβ-hybrid peptoids were introduced as the backbone modification in peptidomimetics. In addition to their facile synthesis, these modifications have the possibility of introducing otherwise impossible conformations in the peptide backbone.

  3. Segmental arterial mediolysis mimics systemic vasculitis

    PubMed Central

    Kalfa, Melike; Kocanaoğulları, Hayriye; Karabulut, Gonca; Emmungil, Hakan; Çınar, Celal; Yılmaz, Zevcet; Gücenmez, Sercan; Kabasakal, Yasemin

    2016-01-01

    Segmental arterial mediolysis (SAM) is a rare, nonarteriosclerotic, noninflammatory vascular disease and mostly affects medium-to-large sized abdominal arteries as well as presents with hemorrhages in the abdominal cavity. We report the case of a patient with SAM of the celiac, right renal, jejunal branch of the superior mesenteric, left gastric, and splenic arteries who was diagnosed by excluding other causes and in whom transcatheter embolization was performed in two different sessions, but he died because of an undefined reason. SAM mimics systemic vasculitis and causes abdominal pain; it should be considered because abdominal hemorrhage or arterial infarction can result in death. PMID:27733945

  4. Oxidoreductase mimic activity of natural pyrrhotite

    NASA Astrophysics Data System (ADS)

    Ibáñez de Aldecoa, A. L.; Velasco, F.; Menor-Salván, C.

    2012-09-01

    The theory of the chemo-autotrophic origin of life, also called the "iron-sulfur world hypothesis", proposes that the system FeS/FeS2 present in the primitive Earth crust gave the reductive power necessary to conduct the first protometabolic redox reactions. Some experimental studies demonstrated the redox activity of the FeS/SH2 system, but none of them used natural FeS. Here, we show that the iron sulfide mineral pyrrhotite is able to mimic the redox activity of the enzyme lactate dehydrogenase, which reversibly reduces the pyruvate in lactate, under prebiotic conditions with pyrite formation.

  5. 75 FR 51519 - Regional Transportation District-Acquisition Exemption-Union Pacific Railroad Company in Adams...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-20

    ... Railroad Company in Adams, Denver, and Jefferson Counties, CO Regional Transportation District (RTD) \\1... Subdivision extending approximately 8.96 miles, from milepost 628.50, in Adams County, CO., to milepost...

  6. 77 FR 60004 - Culturally Significant Object Imported for Exhibition Determinations: “Wtewael's Adam and Eve”

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Object Imported for Exhibition Determinations: ``Wtewael's Adam and Eve'' SUMMARY... object to be included in the exhibition ``Wtewael's Adam and Eve,'' imported from abroad for...

  7. The Role of ADAM9 in Tumor-Stromal Interactions in Breast Cancer

    DTIC Science & Technology

    2009-04-01

    endogenously express ADAM9-L and –S (Fig 1 ). Year two research focused on using isoform specific antibodies for immunocytochemistry in preparation for...migration. As outlined in the task 2 update, we have shown that the different isoforms of ADAM9 have opposing effects on breast cancer cell migration...both isoforms of ADAM-9, and our future work in this area will further define the relevant signaling pathways which participate in ADAM9 mediated

  8. A study of the association between the ADAM12 and SH3PXD2A (SH3MD1) genes and Alzheimer's disease.

    PubMed

    Laumet, Geoffroy; Petitprez, Vincent; Sillaire, Adeline; Ayral, Anne-Marie; Hansmannel, Franck; Chapuis, Julien; Hannequin, Didier; Pasquier, Florence; Scarpini, Elio; Galimberti, Daniela; Lendon, Corinne; Campion, Dominique; Amouyel, Philippe; Lambert, Jean-Charles

    2010-01-01

    Several observations suggest that neurotoxicity in Alzheimer's disease (AD) can be partly attributed to beta-amyloid (Abeta) and senile plaques. Recent work has suggested that the FISH (five SH3 domains) adapter protein and ADAM12 (a disintegrin and metalloprotease) may mediate the neurotoxic effect of Abeta. Both genes are located on chromosome 10, within a region linked to AD (for SH3PXD2A) or nearby (for ADAM12). A recent study reported a statistically significant interaction between 2 variants of these genes (rs3740473 for SH3PXD2A and rs11244787 for ADAM12) with respect to the risk of developing AD. With a view to replicating this observation, we genotyped the two SNPs in four European case-control cohorts of Caucasian origin (1913 cases and 1468 controls) but were unable to confirm the initial results.

  9. Father Knows Best: Using Adam Smith to Teach Transactions Costs

    ERIC Educational Resources Information Center

    Dupont, Brandon

    2014-01-01

    Adam Smith's moral philosophy can be used to introduce economics students to the important idea of transactions costs. The author provides a brief background in this article to Smith's moral philosophy and connects it to the costs of transacting in a way that fits easily into the standard principles of microeconomics classroom. By doing…

  10. The ADaptation and Anticipation Model (ADAM) of sensorimotor synchronization

    PubMed Central

    van der Steen, M. C. (Marieke); Keller, Peter E.

    2013-01-01

    A constantly changing environment requires precise yet flexible timing of movements. Sensorimotor synchronization (SMS)—the temporal coordination of an action with events in a predictable external rhythm—is a fundamental human skill that contributes to optimal sensory-motor control in daily life. A large body of research related to SMS has focused on adaptive error correction mechanisms that support the synchronization of periodic movements (e.g., finger taps) with events in regular pacing sequences. The results of recent studies additionally highlight the importance of anticipatory mechanisms that support temporal prediction in the context of SMS with sequences that contain tempo changes. To investigate the role of adaptation and anticipatory mechanisms in SMS we introduce ADAM: an ADaptation and Anticipation Model. ADAM combines reactive error correction processes (adaptation) with predictive temporal extrapolation processes (anticipation) inspired by the computational neuroscience concept of internal models. The combination of simulations and experimental manipulations based on ADAM creates a novel and promising approach for exploring adaptation and anticipation in SMS. The current paper describes the conceptual basis and architecture of ADAM. PMID:23772211

  11. What Ever Happened to . . . John Adams High School?

    ERIC Educational Resources Information Center

    Doremus, Richard R.

    1981-01-01

    First in a series, this article describes the rise and fall of John Adams High School, an experimental school in Portland (Oregon) that was recently closed after 12 years of operation. The experiences of those who tried to make the experiment work may help others interested in educational innovation. (WD)

  12. "The Adams Chronicles" and the American History Survey

    ERIC Educational Resources Information Center

    Rollins, Richard M.

    1977-01-01

    Film documentaries can be a valuable addition to introductory American history courses. Using "The Adams Chronicles" as an example, the author identifies flaws in the film and then explains how careful planning and analysis of the video and printed programs enabled him to incorporate it effectively into a freshman-level survey course at Ohio State…

  13. Adam Smith and the Moral Economy of the Classroom System.

    ERIC Educational Resources Information Center

    Hamilton, D.

    1980-01-01

    Traces the development of mass schooling to its origins in 19th-century Glasgow. Its importance as an intellectual and economic center enabled Glasgow to invent a solution to the problem of urban schooling, while the association of scholars like Adam Smith with Glasgow University made Scottish educational theories acceptable around the world. (DB)

  14. Adam Smith and the Teaching of English Literature.

    ERIC Educational Resources Information Center

    Court, Franklin E.

    1985-01-01

    Adam Smith used selections from English literature in his classroom during the eighteenth century because he believed that vernacular literature could provide a ready context for the teaching of ideological, social, and moral lessons. He believed that higher education should prepare students for the real business of the real world. (RM)

  15. An Informal Report on Collegiate Successes with "The Adams Chronicles."

    ERIC Educational Resources Information Center

    Goldsberry, Gary G.

    In the spring of 1976, "The Adams Chronicles", a bicentennial television course developed by Coast Community College District and the University of California at San Diego, was distributed to colleges nationwide at no charge with the understanding that each college would return information regarding promotion, enrollment, and form of…

  16. 5. Aerial view west, Adams Dam Road bottom center, State ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Aerial view west, Adams Dam Road bottom center, State Route 100 center, duck pond and reservoir center, State Route 100 center right, State Route 92 below center right, Brandywine Creek State Park center bottom. - Winterthur Farms, Intersection State Routes 92 & 100, Intersection State Routes 92 & 100, Winterthur, New Castle County, DE

  17. 4. Aerial view southwest, Adams Dam Road bottom left, State ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Aerial view southwest, Adams Dam Road bottom left, State Route 100 center, back gates to Winterthur and Wilmington Country Club upper center, duck pond and reservoir bottom right and center, and State Route 92 center bottom. - Winterthur Farms, Intersection State Routes 92 & 100, Intersection State Routes 92 & 100, Winterthur, New Castle County, DE

  18. 3. Aerial view southeast, State Route 92 bottom left, Adams ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Aerial view southeast, State Route 92 bottom left, Adams Dam Road center, Brandywine Creek State Park and J. Chandler Farm in center left, duck pond bottom right and reservoir bottom left. - Winterthur Farms, Intersection State Routes 92 & 100, Intersection State Routes 92 & 100, Winterthur, New Castle County, DE

  19. Selective Loss of Presynaptic Potassium Channel Clusters at the Cerebellar Basket Cell Terminal Pinceau in Adam11 Mutants Reveals Their Role in Ephaptic Control of Purkinje Cell Firing

    PubMed Central

    Kole, Matthew J.; Qian, Jing; Waase, Marc P.; Klassen, Tara L.; Chen, Tim T.; Augustine, George J.

    2015-01-01

    A specialized axonal ending, the basket cell “pinceau,” encapsulates the Purkinje cell axon initial segment (AIS), exerting final inhibitory control over the integrated outflow of the cerebellar cortex. This nonconventional axo-axonic contact extends beyond the perisomatic chemical GABAergic synaptic boutons to the distal AIS, lacks both sodium channels and local exocytotic machinery, and yet contains a dense cluster of voltage-gated potassium channels whose functional contribution is unknown. Here, we show that ADAM11, a transmembrane noncatalytic disintegrin, is the first reported Kv1-interacting protein essential for localizing Kv1.1 and Kv1.2 subunit complexes to the distal terminal. Selective absence of these channels at the pinceau due to mutation of ADAM11 spares spontaneous GABA release from basket cells at the perisomatic synapse yet eliminates ultrarapid ephaptic inhibitory synchronization of Purkinje cell firing. Our findings identify a critical role for presynaptic K+ channels at the pinceau in ephaptic control over the speed and stability of spike rate coding at the Purkinje cell AIS in mice. SIGNIFICANCE STATEMENT This study identifies ADAM11 as the first essential molecule for the proper localization of potassium ion channels at presynaptic nerve terminals, where they modulate excitability and the release of neural transmitters. Genetic truncation of the transmembrane disintegrin and metalloproteinase protein ADAM11 resulted in the absence of Kv1 channels that are normally densely clustered at the terminals of basket cell axons in the cerebellar cortex. These specialized terminals are responsible for the release of the neurotransmitter GABA onto Purkinje cells and also display electrical signaling. In the ADAM11 mutant, GABAergic release was not altered, but the ultrarapid electrical signal was absent, demonstrating that the dense presynaptic cluster of Kv1 ion channels at these terminals mediate electrical transmission. Therefore, ADAM11 plays a

  20. Tumor necrosis factor-alpha convertase (ADAM17) mediates regulated ectodomain shedding of the severe-acute respiratory syndrome-coronavirus (SARS-CoV) receptor, angiotensin-converting enzyme-2 (ACE2).

    PubMed

    Lambert, Daniel W; Yarski, Mike; Warner, Fiona J; Thornhill, Paul; Parkin, Edward T; Smith, A Ian; Hooper, Nigel M; Turner, Anthony J

    2005-08-26

    Angiotensin-converting enzyme-2 (ACE2) is a critical regulator of heart function and a cellular receptor for the causative agent of severe-acute respiratory syndrome (SARS), SARS-CoV (coronavirus). ACE2 is a type I transmembrane protein, with an extracellular N-terminal domain containing the active site and a short intracellular C-terminal tail. A soluble form of ACE2, lacking its cytosolic and transmembrane domains, has been shown to block binding of the SARS-CoV spike protein to its receptor. In this study, we examined the ability of ACE2 to undergo proteolytic shedding and investigated the mechanisms responsible for this shedding event. We demonstrated that ACE2, heterologously expressed in HEK293 cells and endogenously expressed in Huh7 cells, undergoes metalloproteinase-mediated, phorbol ester-inducible ectodomain shedding. By using inhibitors with differing potency toward different members of the ADAM (a disintegrin and metalloproteinase) family of proteases, we identified ADAM17 as a candidate mediator of stimulated ACE2 shedding. Furthermore, ablation of ADAM17 expression using specific small interfering RNA duplexes reduced regulated ACE2 shedding, whereas overexpression of ADAM17 significantly increased shedding. Taken together, these data provided direct evidence for the involvement of ADAM17 in the regulated ectodomain shedding of ACE2. The identification of ADAM17 as the protease responsible for ACE2 shedding may provide new insight into the physiological roles of ACE2.

  1. Preparation of highly efficient manganese catalase mimics.

    PubMed

    Triller, Michael U; Hsieh, Wen-Yuan; Pecoraro, Vincent L; Rompel, Annette; Krebs, Bernt

    2002-10-21

    The series of compounds [Mn(bpia)(mu-OAc)](2)(ClO(4))(2) (1), [Mn(2)(bpia)(2)(muO)(mu-OAc)](ClO(4))(3).CH(3)CN (2), [Mn(bpia)(mu-O)](2)(ClO(4))(2)(PF(6)).2CH(3)CN (3), [Mn(bpia)(Cl)(2)](ClO)(4) (4), and [(Mn(bpia)(Cl))(2)(mu-O)](ClO(4))(2).2CH(3)CN (5) (bpia = bis(picolyl)(N-methylimidazol-2-yl)amine) represents a structural, spectroscopic, and functional model system for manganese catalases. Compounds 3 and 5 have been synthesized from 2 via bulk electrolysis and ligand exchange, respectively. All complexes have been structurally characterized by X-ray crystallography and by UV-vis and EPR spectroscopies. The different bridging ligands including the rare mono-mu-oxo and mono-mu-oxo-mono-mu-carboxylato motifs lead to a variation of the Mn-Mn separation across the four binuclear compounds of 1.50 A (Mn(2)(II,II) = 4.128 A, Mn(2)(III,III) = 3.5326 and 3.2533 A, Mn(2)(III,IV) = 2.624 A). Complexes 1, 2, and 3 are mimics for the Mn(2)(II,II), the Mn(2)(III,III), and the Mn(2)(III,IV) oxidation states of the native enzyme. UV-vis spectra of these compounds show similarities to those of the corresponding oxidation states of manganese catalase from Thermus thermophilus and Lactobacillus plantarum. Compound 2 exhibits a rare example of a Jahn-Teller compression. While complexes 1 and 3 are efficient catalysts for the disproportionation of hydrogen peroxide and contain an N(4)O(2) donor set, 4 and 5 show no catalase activity. These complexes have an N(4)Cl(2) and N(4)OCl donor set, respectively, and serve as mimics for halide inhibited manganese catalases. Cyclovoltammetric data show that the substitution of oxygen donor atoms with chloride causes a shift of redox potentials to more positive values. To our knowledge, complex 1 is the most efficient binuclear functional manganese catalase mimic exhibiting saturation kinetics to date.

  2. Fisetin suppresses ADAM9 expression and inhibits invasion of glioma cancer cells through increased phosphorylation of ERK1/2.

    PubMed

    Chen, Chien-Min; Hsieh, Yi-Hsien; Hwang, Jin-Ming; Jan, Hsun-Jin; Hsieh, Shu-Ching; Lin, Shin-Huey; Lai, Chung-Yu

    2015-05-01

    Fisetin (3,3',4',7-tetrahydroxyflavone) is a naturally occurring flavonoid which is widely distributed in plants. It has been reported to possess some anticancer and anti-invasive capabilities. We set out to explore the effects of fisetin on antimetastatic and its mechanism of action in GBM8401 cells. The results indicated that fisetin exhibited effective inhibition of cell migration and inhibited the invasion of GBM8401 cells under non-cytotoxic concentrations. To identify the potential targets of fisetin, human proteinase antibody array analysis was performed, and the results indicated that the fisetin treatment inhibited the expression of ADAM9 protein and mRNA, which are known to contribute to the progression of glioma cancer. Our results showed that fisetin phosphorylated ERK1/2 in a sustained way that contributed to the inhibited ADAM9 protein and mRNA expression determined by Western blot and RT-PCR. Moreover, inhibition of ERK1/2 by U0126 or transfection with the siERK plasmid significantly abolished the fisetin-inhibited migration and invasion through activation of the ERK1/2 pathway. In summary, our results suggest that fisetin might be a potential therapeutic agent against human glioma cells based on its capacity to activate ERK1/2 and to inhibit ADAM9 expression.

  3. Evaluating minimalist mimics by exploring key orientations on secondary structures (EKOS).

    PubMed

    Xin, Dongyue; Ko, Eunhwa; Perez, Lisa M; Ioerger, Thomas R; Burgess, Kevin

    2013-11-28

    + 3, i + 4) of those overlays, and the energy of this state relative to the minimum located. This protocol was tested on some of the most widely cited minimalist α-helical mimics (1-8 in the text). The data obtained indicates several of these compounds preferentially exist in conformations that resemble other secondary structures as well as α-helices, and many of the α-helical conformations have unexpected side-chain correspondences. These observations imply the featured minimalist mimics have more scope for disrupting PPI interfaces than previously anticipated. Finally, the same simulation method was used to match preferred conformations of minimalist mimics with actual protein/peptide structures at interfaces providing quantitative comparisons of predicted fits of the test mimics at protein-protein interaction sites.

  4. Permanent female mimics in a lekking shorebird.

    PubMed

    Jukema, Joop; Piersma, Theunis

    2006-06-22

    Female mimics are known from many species, but permanent, non-conditional, alternative mating strategies are only known from an isopod, a fish, a lizard and a bird. The single bird example refers to lek-breeding ruffs Philomachus pugnax, a shorebird for which two strategies (independent and satellite) have been known for over 50 years. Ruffs also provided the single case of an animal with two, rather than three, permanent alternative mating strategies. Here, we describe a rare female-like morph of ruffs: the 'missing' third alternative mating strategy, which we have called 'faeder'. Faeders are slightly larger than females and in late April have testes 2.5 time the size of testes of normal males. On leks in aviaries and in the wild they appear to combine feminine and masculine behaviours. Faeders may represent the ancestral, care-giving, male strategy, but their relatively large testes suggest that currently they behave as sneakers.

  5. Daughters mimic sterile neutrinos (almost!) perfectly

    NASA Astrophysics Data System (ADS)

    Hasenkamp, Jasper

    2014-09-01

    Since only recently, cosmological observations are sensitive to hot dark matter (HDM) admixtures with sub-eV mass, mhdmeff < eV, that are not fully-thermalised, Δ Neff < 1. We argue that their almost automatic interpretation as a sterile neutrino species is neither from theoretical nor practical parsimony principles preferred over HDM formed by decay products (daughters) of an out-of-equilibrium particle decay. While daughters mimic sterile neutrinos in Neff and mhdmeff, there are opportunities to assess this possibility in likelihood analyses. Connecting cosmological parameters and moments of momentum distribution functions, we show that—also in the case of mass-degenerate daughters with indistinguishable main physical effects—the mimicry breaks down when the next moment, the skewness, is considered. Predicted differences of order one in the root-mean-squares of absolute momenta are too small for current sensitivities.

  6. Recognizing asthma mimics and asthma complications.

    PubMed

    Amundson, Dennis; Seda, Gilbert; Daheshia, Massoud

    2011-10-01

    Asthma is a chronic inflammatory disorder of the airways characterized by airflow obstruction, bronchial hyperreactivity, and underlying inflammation. Two common reasons asthmatics fail standard therapy are incorrect diagnosis and failure to recognize underlying contributing factors. A correct diagnosis of asthma is of great importance to military practitioners since misdiagnosis or uncontrolled asthma affects an individual's operational readiness or determines whether one can receive a medical waiver to enlist in military service. This article presents four cases of patients with dyspnea that have conditions which mimic asthma or complicate asthma management: vocal cord dysfunction misdiagnosed as asthma, respiratory bronchiolitis interstitial lung disease mistaken as asthma, difficult-to-control asthma because of bronchiectasis and allergic bronchopulmonary aspergillosis, and difficult and fatal asthma. Asthma is contrasted to other respiratory disorders, and an outlined approach to asthma diagnosis and management is presented using the Global Initiative for Asthma guidelines.

  7. Renewable polyethylene mimics derived from castor oil.

    PubMed

    Türünç, Oĝuz; Montero de Espinosa, Lucas; Meier, Michael A R

    2011-09-01

    An increasing number of reports on the syntheses of carbohydrate- and plant oil-based polymers has been published in ongoing efforts to produce plastic materials from renewable resources. Although many of these polymers are biodegradable and this is a desirable property for certain applications, in some cases non-degradable polymers are needed for long-term use purposes. Polyolefins are one of the most important classes of materials that have already taken their places in our daily life. On the other hand, their production relies on fossil resources. Therefore, within this contribution, we discuss synthetic routes toward a number of polyethylene mimics derived from fatty acids via thiol-ene and ADMET polymerization reactions in order to establish more sustainable routes toward this important class of polymers. Two different diene monomers were thus prepared from castor oil derived platform chemicals, their polymerization via the two mentioned routes was optimized and compared to each other, and their thermal properties were investigated.

  8. Bell's palsy syndrome: mimics and chameleons.

    PubMed

    Fuller, Geraint; Morgan, Cathy

    2016-12-01

    In this article we will explore the mimics and chameleons of Bell's palsy and in addition argue that we should use the term 'Bell's palsy syndrome' to help guide clinical reasoning when thinking about patients with facial weakness. The diagnosis of Bell's palsy can usually be made on clinical grounds without the need for further investigations. This is because the diagnosis is not one of exclusion (despite this being commonly how it is described), a lower motor neurone facial weakness where all alternative causes have been eliminated, but rather a positive recognition of a clinical syndrome, with a number of exclusions, which are described below. This perhaps would be more accurately referred to a 'Bell's palsy syndrome'. Treatment with corticosteroids improves outcome; adding an antiviral probably reduces the rates of long-term complications.

  9. Tiny Device Mimics Human Lung Function

    SciTech Connect

    McDonald, Rebecca; Harris, Jennifer; Nath, Pulak

    2016-04-25

    Scientists at Los Alamos National Laboratory are developing a miniature, tissue-engineered artificial lung that mimics the response of the human lung to drugs, toxins and other agents. “We breathe in and out thousands of times every day. And while we have control over what we eat or drink, we don’t always have control over what we breathe in,” said Jennifer Harris of Biosecurity and Public Health at Los Alamos, "and so we’re making this miniature lung to be able to test on actual human cells whether something in the environment, or a drug, is toxic or harmful to us." Nicknamed “PuLMo” for Pulmonary Lung Model (Pulmo is also the Latin word for "lung")the device consists of two major parts, the bronchiolar unit and the alveolar unit—just like the human lung. The units are primarily made from various polymers and are connected by a microfluidic “circuit board” that manages fluid and air flow. “When we build our lung, we not only take into account the aspects of different cell types, the tissues that are involved, we also take into account that a lung is supposed to breathe, so PuLMo actually breathes,” said Pulak Nath of Applied Modern Physics, who leads engineering efforts for the project. The most exciting application of PuLMo is a potentially revolutionary improvement in the reliability of drug-toxicity assessments and the prediction of new pharmaceutical success in humans, according to Harris. The PuLMo may also be designed to mimic lung disease conditions, such as Chronic Obstructive Pulmonary Disease (COPD) and asthma, and may be used to study lung air-flow dynamics to better understand the mechanisms of toxins and drug delivery and the effects of smoking, particularly the less-understood effects of e-cigarettes.

  10. Metalloproteinase inhibitors for the disintegrin-like metalloproteinases ADAM10 and ADAM17 that differentially block constitutive and phorbol ester-inducible shedding of cell surface molecules.

    PubMed

    Ludwig, Andreas; Hundhausen, Christian; Lambert, Millard H; Broadway, Neil; Andrews, Robert C; Bickett, D Mark; Leesnitzer, M Anthony; Becherer, J David

    2005-03-01

    The transmembrane metzinkin-proteases of the ADAM (a disintegrin and a metalloproteinase)-family ADAM10 and ADAM 17 are both implicated in the ectodomain shedding of various cell surface molecules including the IL6-receptor and the transmembrane chemokines CX3CL1 and CXCL16. These molecules are constitutively released from cultured cells, a process that can be rapidly enhanced by cell stimulation with phorbol esters such as PMA. Recent research supports the view that the constitutive cleavage predominantly involves ADAM10 while the inducible one is mediated to a large extent by ADAM17. We here describe the discovery of hydroxamate compounds with different potency against ADAM10 and ADAM17 and different ability to block constitutive and inducible cleavage of IL6R, CX3CL1 and CXCL16 by the two proteases. By screening a number of hydroxamate inhibitors for the inhibition of recombinant metalloproteinases, a compound was found inhibiting ADAM10 with more than 100-fold higher potency than ADAM17, which may be explained by an improved fit of the compound to the S1' specificity pocket of ADAM10 as compared to that of ADAM17. In cell-based cleavage experiments this compound (GI254023X) potently blocked the constitutive release of IL6R, CX3CL1 and CXCL16, which was in line with the reported involvement of ADAM10 but not ADAM17 in this process. By contrast, the compound did not affect the PMA-induced shedding, which was only blocked by GW280264X, a potent inhibitor of ADAM17. As expected, GI254023X did not further decrease the residual release of CX3CL1 and CXCL16 in ADAM10-deficient cells verifying that the compound's effect on the constitutive shedding of these molecules was exclusively due to the inhibition of ADAM10. Thus, GI254023X may by of use as a preferential inhibitor of constitutive shedding events without effecting the inducible shedding in response to agonists acting similar to PMA.

  11. ADAM17 silencing in mouse colon carcinoma cells: the effect on tumoricidal cytokines and angiogenesis.

    PubMed

    Das, Sudipta; Czarnek, Maria; Bzowska, Monika; Mężyk-Kopeć, Renata; Stalińska, Krystyna; Wyroba, Barbara; Sroka, Jolanta; Jucha, Jarosław; Deneka, Dawid; Stokłosa, Paulina; Ogonek, Justyna; Swartz, Melody A; Madeja, Zbigniew; Bereta, Joanna

    2012-01-01

    ADAM17 (a disintegrin and metalloprotease 17) is a major sheddase for numerous growth factors, cytokines, receptors, and cell adhesion molecules and is often overexpressed in malignant cells. It is generally accepted that ADAM17 promotes tumor development via activating growth factors from the EGF family, thus facilitating autocrine stimulation of tumor cell proliferation and migration. Here we show, using MC38CEA murine colon carcinoma model, that ADAM17 also regulates tumor angiogenesis and cytokine profile. When ADAM17 was silenced in MC38CEA cells, in vivo tumor growth and in vitro cell motility were significantly diminished, but no effect was seen on in vitro cell proliferation. ADAM17-silencing was accompanied by decreased in vitro expression of vascular endothelial growth factor-A and matrix metalloprotease-9, which was consistent with the limited angiogenesis and slower growth seen in ADAM17-silenced tumors. Among the growth factors susceptible to shedding by ADAM17, neuregulin-1 was the only candidate to mediate the effects of ADAM17 on MC38CEA motility and tumor angiogenesis. Concentrations of TNF and IFNγ, cytokines that synergistically induced proapoptotic effects on MC38CEA cells, were significantly elevated in the lysates of ADAM17-silenced tumors compared to mock transfected controls, suggesting a possible role for ADAM17 in host immune suppression. These results introduce new, complex roles of ADAM17 in tumor progression, including its impact on the anti-tumor immune response.

  12. A disintegrin and metalloprotease 10 (ADAM10) is a central regulator of murine liver tissue homeostasis

    PubMed Central

    Köhn-Gaone, Julia; Chalupsky, Karel; Lüllmann-Rauch, Renate; Barikbin, Roja; Bergmann, Juri; Wöhner, Birte; Zbodakova, Olga; Leuschner, Ivo; Martin, Gregor; Tiegs, Gisa; Rose-John, Stefan; Sedlacek, Radislav; Tirnitz-Parker, Janina E.E.; Saftig, Paul; Schmidt-Arras, Dirk

    2016-01-01

    A Disintegrin And Metalloprotease (ADAM) 10 exerts essential roles during organ development and tissue integrity in different organs, mainly through activation of the Notch pathway. However, only little is known about its implication in liver tissue physiology. Here we show that in contrast to its role in other tissues, ADAM10 is dispensable for the Notch2-dependent biliary tree formation. However, we demonstrate that expression of bile acid transporters is dependent on ADAM10. Consequently, mice deficient for Adam10 in hepatocytes, cholangiocytes and liver progenitor cells develop spontaneous hepatocyte necrosis and concomitant liver fibrosis. We furthermore observed a strongly augmented ductular reaction in 15-week old ADAM10Δhep/Δch mice and demonstrate that c-Met dependent liver progenitor cell activation is enhanced. Additionally, liver progenitor cells are primed to hepatocyte differentiation in the absence of ADAM10. These findings show that ADAM10 is a novel central node controlling liver tissue homeostasis. Highlights: Loss of ADAM10 in murine liver results in hepatocyte necrosis and concomitant liver fibrosis. ADAM10 directly regulates expression of bile acid transporters but is dispensable for Notch2-dependent formation of the biliary system. Activation of liver progenitor cells is enhanced through increased c-Met signalling, in the absence of ADAM10. Differentiation of liver progenitor cells to hepatocytes is augmented in the absence of ADAM10. PMID:26942887

  13. Transgenic overexpression of ADAM12 suppresses muscle regeneration and aggravates dystrophy in aged mdx mice.

    PubMed

    Jørgensen, Louise Helskov; Jensen, Charlotte Harken; Wewer, Ulla M; Schrøder, Henrik Daa

    2007-11-01

    Muscular dystrophies are characterized by insufficient restoration and gradual replacement of the skeletal muscle by fat and connective tissue. ADAM12 has previously been shown to alleviate the pathology of young dystrophin-deficient mdx mice, a model for Duchenne muscular dystrophy. The observed effect of ADAM12 was suggested to be mediated via a membrane-stabilizing up-regulation of utrophin, alpha7B integrin, and dystroglycans. Ectopic ADAM12 expression in normal mouse skeletal muscle also improved regeneration after freeze injury, presumably by the same mechanism. Hence, it was suggested that ADAM12 could be a candidate for nonreplacement gene therapy of Duchenne muscular dystrophy. We therefore evaluated the long-term effect of ADAM12 overexpression in muscle. Surprisingly, we observed loss of skeletal muscle and accelerated fibrosis and adipogenesis in 1-year-old mdx mice transgenically overexpressing ADAM12 (ADAM12(+)/mdx mice), even though their utrophin levels were mildly elevated compared with age-matched controls. Thus, membrane stabilization was not sufficient to provide protection during prolonged disease. Consequently, we reinvestigated skeletal muscle regeneration in ADAM12 transgenic mice (ADAM12(+)) after a knife cut lesion and observed that the regeneration process was significantly impaired. ADAM12 seemed to inhibit the satellite cell response and delay myoblast differentiation. These results discourage long-term therapeutic use of ADAM12. They also point to impaired regeneration as a possible factor in development of muscular dystrophy.

  14. ADAM17 Silencing in Mouse Colon Carcinoma Cells: The Effect on Tumoricidal Cytokines and Angiogenesis

    PubMed Central

    Das, Sudipta; Czarnek, Maria; Bzowska, Monika; Mężyk-Kopeć, Renata; Stalińska, Krystyna; Wyroba, Barbara; Sroka, Jolanta; Jucha, Jarosław; Deneka, Dawid; Stokłosa, Paulina; Ogonek, Justyna; Swartz, Melody A.; Madeja, Zbigniew; Bereta, Joanna

    2012-01-01

    ADAM17 (a disintegrin and metalloprotease 17) is a major sheddase for numerous growth factors, cytokines, receptors, and cell adhesion molecules and is often overexpressed in malignant cells. It is generally accepted that ADAM17 promotes tumor development via activating growth factors from the EGF family, thus facilitating autocrine stimulation of tumor cell proliferation and migration. Here we show, using MC38CEA murine colon carcinoma model, that ADAM17 also regulates tumor angiogenesis and cytokine profile. When ADAM17 was silenced in MC38CEA cells, in vivo tumor growth and in vitro cell motility were significantly diminished, but no effect was seen on in vitro cell proliferation. ADAM17-silencing was accompanied by decreased in vitro expression of vascular endothelial growth factor-A and matrix metalloprotease-9, which was consistent with the limited angiogenesis and slower growth seen in ADAM17-silenced tumors. Among the growth factors susceptible to shedding by ADAM17, neuregulin-1 was the only candidate to mediate the effects of ADAM17 on MC38CEA motility and tumor angiogenesis. Concentrations of TNF and IFNγ, cytokines that synergistically induced proapoptotic effects on MC38CEA cells, were significantly elevated in the lysates of ADAM17-silenced tumors compared to mock transfected controls, suggesting a possible role for ADAM17 in host immune suppression. These results introduce new, complex roles of ADAM17 in tumor progression, including its impact on the anti-tumor immune response. PMID:23251384

  15. Nonyloxytryptamine Mimics Polysialic Acid and Modulates Neuronal and Glial Functions in Cell Culture

    DTIC Science & Technology

    2014-01-01

    protein MAP2 in cultured neuroblastoma cells. These results demonstrate that 5-nonyloxytryptamine mimics Received May 27, 2013; revised manuscript...adhesion molecule (NCAM) and its polysialylated form PSA-NCAM and reduces expression of the microtubuleassociated protein MAP2 in cultured neuroblastoma ...origin and a neuroblastoma cell line as model for easy manipulation (Gotti et al. 1987). Our results show that 5-nonyloxytryptamine binds to a PSA

  16. ADAM28: a potential oncogene involved in asbestos-related lung adenocarcinomas.

    PubMed

    Wright, Casey M; Larsen, Jill E; Hayward, Nicholas K; Martins, Maria U; Tan, Maxine E; Davidson, Morgan R; Savarimuthu, Santiyagu M; McLachlan, Rebecca E; Passmore, Linda H; Windsor, Morgan N; Clarke, Belinda E; Duhig, Edwina E; Yang, Ian A; Bowman, Rayleen V; Fong, Kwun M

    2010-08-01

    Asbestos-related lung cancer accounts for 4-12% of all lung cancers worldwide. Since putative mechanisms of carcinogenesis differ between asbestos and tobacco induced lung cancers, tumors induced by the two agents may be genetically distinct. To identify gene expression biomarkers associated with asbestos-related lung tumorigenicity we performed gene expression array analysis on tumors of 36 patients with primary lung adenocarcinoma, comparing 12 patients with lung asbestos body counts above levels associated with urban dwelling (ARLC-AC: asbestos-related lung cancer-adenocarcinoma) with 24 patients with no asbestos bodies (NARLC-AC: non-asbestos related lung cancer-adenocarcinoma). Genes differentially expressed between ARLC-AC and NARLC-AC were identified on fold change and P value, and then prioritized using gene ontology. Candidates included ZNRF3, ADAM28, PPP1CA, IRF6, RAB3D, and PRDX1. Expression of these six genes was technically and biologically replicated by qRT-PCR in the training set and biologically validated in three independent test sets. ADAM28, encoding a disintegrin and metalloproteinase domain protein that interacts with integrins, was consistently upregulated in ARLC across all four datasets. Further studies are being designed to investigate the possible role of this gene in asbestos lung tumorigenicity, its potential utility as a marker of asbestos related lung cancer for purposes of causal attribution, and its potential as a treatment target for lung cancers arising in asbestos exposed persons.

  17. ADAM12 produced by tumor cells rather than stromal cells accelerates breast tumor progression.

    PubMed

    Fröhlich, Camilla; Nehammer, Camilla; Albrechtsen, Reidar; Kronqvist, Pauliina; Kveiborg, Marie; Sehara-Fujisawa, Atsuko; Mercurio, Arthur M; Wewer, Ulla M

    2011-11-01

    Expression of ADAM12 is low in most normal tissues but is markedly increased in numerous human cancers, including breast carcinomas. We have previously shown that overexpression of ADAM12 accelerates tumor progression in a mouse model of breast cancer (PyMT). In this study, we found that ADAM12 deficiency reduces breast tumor progression in the PyMT model. However, the catalytic activity of ADAM12 seems to be dispensable for its tumor-promoting effect. Interestingly, we show that ADAM12 endogenously expressed in tumor-associated stroma in the PyMT model does not influence tumor progression, but that ADAM12 expression by tumor cells is necessary for tumor progression in these mice. This finding is consistent with our observation that in human breast carcinoma, ADAM12 is almost exclusively located in tumor cells and, only rarely, seen in the tumor-associated stroma. We hypothesized, however, that the tumor-associated stroma may stimulate ADAM12 expression in tumor cells, on the basis of the fact that TGF-β1 stimulates ADAM12 expression and is a well-known growth factor released from tumor-associated stroma. TGF-β1 stimulation of ADAM12-negative Lewis lung tumor cells induced ADAM12 synthesis, and growth of these cells in vivo induced more than 200-fold increase in ADAM12 expression. Our observation that ADAM12 expression is significantly higher in the terminal duct lobular units (TDLU) adjacent to human breast carcinoma compared with TDLUs found in normal breast tissue supports our hypothesis that tumor-associated stroma triggers ADAM12 expression.

  18. Adams-Based Rover Terramechanics and Mobility Simulator - ARTEMIS

    NASA Technical Reports Server (NTRS)

    Trease, Brian P.; Lindeman, Randel A.; Arvidson, Raymond E.; Bennett, Keith; VanDyke, Lauren P.; Zhou, Feng; Iagnemma, Karl; Senatore, Carmine

    2013-01-01

    The Mars Exploration Rovers (MERs), Spirit and Opportunity, far exceeded their original drive distance expectations and have traveled, at the time of this reporting, a combined 29 kilometers across the surface of Mars. The Rover Sequencing and Visualization Program (RSVP), the current program used to plan drives for MERs, is only a kinematic simulator of rover movement. Therefore, rover response to various terrains and soil types cannot be modeled. Although sandbox experiments attempt to model rover-terrain interaction, these experiments are time-intensive and costly, and they cannot be used within the tactical timeline of rover driving. Imaging techniques and hazard avoidance features on MER help to prevent the rover from traveling over dangerous terrains, but mobility issues have shown that these methods are not always sufficient. ARTEMIS, a dynamic modeling tool for MER, allows planned drives to be simulated before commands are sent to the rover. The deformable soils component of this model allows rover-terrain interactions to be simulated to determine if a particular drive path would take the rover over terrain that would induce hazardous levels of slip or sink. When used in the rover drive planning process, dynamic modeling reduces the likelihood of future mobility issues because high-risk areas could be identified before drive commands are sent to the rover, and drives planned over these areas could be rerouted. The ARTEMIS software consists of several components. These include a preprocessor, Digital Elevation Models (DEMs), Adams rover model, wheel and soil parameter files, MSC Adams GUI (commercial), MSC Adams dynamics solver (commercial), terramechanics subroutines (FORTRAN), a contact detection engine, a soil modification engine, and output DEMs of deformed soil. The preprocessor is used to define the terrain (from a DEM) and define the soil parameters for the terrain file. The Adams rover model is placed in this terrain. Wheel and soil parameter files

  19. Tiny Device Mimics Human Lung Function

    ScienceCinema

    McDonald, Rebecca; Harris, Jennifer; Nath, Pulak

    2016-07-12

    Scientists at Los Alamos National Laboratory are developing a miniature, tissue-engineered artificial lung that mimics the response of the human lung to drugs, toxins and other agents. “We breathe in and out thousands of times every day. And while we have control over what we eat or drink, we don’t always have control over what we breathe in,” said Jennifer Harris of Biosecurity and Public Health at Los Alamos, "and so we’re making this miniature lung to be able to test on actual human cells whether something in the environment, or a drug, is toxic or harmful to us." Nicknamed “PuLMo” for Pulmonary Lung Model (Pulmo is also the Latin word for "lung")the device consists of two major parts, the bronchiolar unit and the alveolar unit—just like the human lung. The units are primarily made from various polymers and are connected by a microfluidic “circuit board” that manages fluid and air flow. “When we build our lung, we not only take into account the aspects of different cell types, the tissues that are involved, we also take into account that a lung is supposed to breathe, so PuLMo actually breathes,” said Pulak Nath of Applied Modern Physics, who leads engineering efforts for the project. The most exciting application of PuLMo is a potentially revolutionary improvement in the reliability of drug-toxicity assessments and the prediction of new pharmaceutical success in humans, according to Harris. The PuLMo may also be designed to mimic lung disease conditions, such as Chronic Obstructive Pulmonary Disease (COPD) and asthma, and may be used to study lung air-flow dynamics to better understand the mechanisms of toxins and drug delivery and the effects of smoking, particularly the less-understood effects of e-cigarettes.

  20. Designed biomaterials to mimic the mechanical properties of muscles.

    PubMed

    Lv, Shanshan; Dudek, Daniel M; Cao, Yi; Balamurali, M M; Gosline, John; Li, Hongbin

    2010-05-06

    The passive elasticity of muscle is largely governed by the I-band part of the giant muscle protein titin, a complex molecular spring composed of a series of individually folded immunoglobulin-like domains as well as largely unstructured unique sequences. These mechanical elements have distinct mechanical properties, and when combined, they provide the desired passive elastic properties of muscle, which are a unique combination of strength, extensibility and resilience. Single-molecule atomic force microscopy (AFM) studies demonstrated that the macroscopic behaviour of titin in intact myofibrils can be reconstituted by combining the mechanical properties of these mechanical elements measured at the single-molecule level. Here we report artificial elastomeric proteins that mimic the molecular architecture of titin through the combination of well-characterized protein domains GB1 and resilin. We show that these artificial elastomeric proteins can be photochemically crosslinked and cast into solid biomaterials. These biomaterials behave as rubber-like materials showing high resilience at low strain and as shock-absorber-like materials at high strain by effectively dissipating energy. These properties are comparable to the passive elastic properties of muscles within the physiological range of sarcomere length and so these materials represent a new muscle-mimetic biomaterial. The mechanical properties of these biomaterials can be fine-tuned by adjusting the composition of the elastomeric proteins, providing the opportunity to develop biomaterials that are mimetic of different types of muscles. We anticipate that these biomaterials will find applications in tissue engineering as scaffold and matrix for artificial muscles.

  1. Platelet integrin α6β1 controls lung metastasis through direct binding to cancer cell–derived ADAM9

    PubMed Central

    Mammadova-Bach, Elmina; Zigrino, Paola; Brucker, Camille; Bourdon, Catherine; Freund, Monique; Abrams, Scott I.; Orend, Gertaud; Gachet, Christian

    2016-01-01

    Metastatic dissemination of cancer cells, which accounts for 90% of cancer mortality, is the ultimate hallmark of malignancy. Growing evidence suggests that blood platelets have a predominant role in tumor metastasis; however, the molecular mechanisms involved remain elusive. Here, we demonstrate that genetic deficiency of integrin α6β1 on platelets markedly decreases experimental and spontaneous lung metastasis. In vitro and in vivo assays reveal that human and mouse platelet α6β1 supports platelet adhesion to various types of cancer cells. Using a knockdown approach, we identified ADAM9 as the major counter receptor of α6β1 on both human and mouse tumor cells. Static and flow-based adhesion assays of platelets binding to DC-9, a recombinant protein covering the disintegrin-cysteine domain of ADAM9, demonstrated that this receptor directly binds to platelet α6β1. In vivo studies showed that the interplay between platelet α6β1 and tumor cell–expressed ADAM9 promotes efficient lung metastasis. The integrin α6β1–dependent platelet-tumor cell interaction induces platelet activation and favors the extravasation process of tumor cells. Finally, we demonstrate that a pharmacological approach targeting α6β1 efficiently impairs tumor metastasis through a platelet-dependent mechanism. Our study reveals a mechanism by which platelets promote tumor metastasis and suggests that integrin α6β1 represents a promising target for antimetastatic therapies. PMID:27699237

  2. Mid-trimester maternal ADAM12 levels differ according to fetal gender in pregnancies complicated by preeclampsia.

    PubMed

    Myers, Jenny E; Thomas, Grégoire; Tuytten, Robin; Van Herrewege, Yven; Djiokep, Raoul O; Roberts, Claire T; Kenny, Louise C; Simpson, Nigel A B; North, Robyn A; Baker, Philip N

    2015-02-01

    An overrepresentation of adverse pregnancy outcomes has been observed in pregnancies associated with a male fetus. We investigated the association between fetal gender and candidate biomarkers for preeclampsia. Proteins were quantified in samples taken at 20 weeks from women recruited to the SCreening fOr Pregnancy Endpoints (SCOPE) study (preeclampsia n = 150; no preeclampsia n = 450). In contrast to placental growth factor, soluble endoglin, and insulin-like growth factor acid labile subunit, levels of metallopeptidase domain 12 (ADAM12) at 20 weeks were dependent on fetal gender in pregnancies complicated by preeclampsia, for male (n = 73) fetuses the multiples of the median (MoM; interquartile range [IQR] 1.1-1.5) was 1.3, whereas for female fetuses (n = 75) MoM was 1.1 (1.0-1.3); P < .01. Prediction of preeclampsia using ADAM12 levels was improved for pregnancies associated with a male fetus (area under receiver-operator curve [AUC] 0.73 [95% confidence interval [CI] 0.67-0.80]) than that of a female fetus (AUC 0.62 [0.55-0.70]); P = .03. The data presented here fit a contemporary hypothesis that there is a difference between the genders in response to an adverse maternal environment and suggest that an alteration in ADAM12 may reflect an altered placental response in pregnancies subsequently complicated by preeclampsia.

  3. Daughters mimic sterile neutrinos (almost!) perfectly

    SciTech Connect

    Hasenkamp, Jasper

    2014-09-01

    Since only recently, cosmological observations are sensitive to hot dark matter (HDM) admixtures with sub-eV mass, m{sub hdm}{sup eff} < eV, that are not fully-thermalised, Δ N{sub eff} < 1. We argue that their almost automatic interpretation as a sterile neutrino species is neither from theoretical nor practical parsimony principles preferred over HDM formed by decay products (daughters) of an out-of-equilibrium particle decay. While daughters mimic sterile neutrinos in N{sub eff} and m{sub hdm}{sup eff}, there are opportunities to assess this possibility in likelihood analyses. Connecting cosmological parameters and moments of momentum distribution functions, we show that—also in the case of mass-degenerate daughters with indistinguishable main physical effects—the mimicry breaks down when the next moment, the skewness, is considered. Predicted differences of order one in the root-mean-squares of absolute momenta are too small for current sensitivities.

  4. System Verification of MSL Skycrane Using an Integrated ADAMS Simulation

    NASA Technical Reports Server (NTRS)

    White, Christopher; Antoun, George; Brugarolas, Paul; Lih, Shyh-Shiuh; Peng, Chia-Yen; Phan, Linh; San Martin, Alejandro; Sell, Steven

    2012-01-01

    Mars Science Laboratory (MSL) will use the Skycrane architecture to execute final descent and landing maneuvers. The Skycrane phase uses closed-loop feedback control throughout the entire phase, starting with rover separation, through mobility deploy, and through touchdown, ending only when the bridles have completely slacked. The integrated ADAMS simulation described in this paper couples complex dynamical models created by the mechanical subsystem with actual GNC flight software algorithms that have been compiled and linked into ADAMS. These integrated simulations provide the project with the best means to verify key Skycrane requirements which have a tightly coupled GNC-Mechanical aspect to them. It also provides the best opportunity to validate the design of the algorithm that determines when to cut the bridles. The results of the simulations show the excellent performance of the Skycrane system.

  5. ADAM: An Axisymmetric Duct Aeroacoustic Modeling system. [aircraft turbofan engines

    NASA Technical Reports Server (NTRS)

    Abrahamson, A. L.

    1983-01-01

    An interconnected system of computer programs for analyzing the propagation and attenuation of sound in aeroengine ducts containing realistic compressible subsonic mean flows, ADAM was developed primarily for research directed towards the reduction of noise emitted from turbofan aircraft engines. The two basic components are a streamtube curvature program for determination of the mean flow, and a finite element code for solution of the acoustic propagation problem. The system, which has been specifically tailored for ease of use, is presently installed at NASA Langley Reseach Center on a Control Data Cyber 175 Computer under the NOS Operating system employing a Tektronix terminal for interactive graphics. The scope and organization of the ADAM system is described. A users guide, examples of input data, and results for selected cases are included.

  6. Empathy's purity, sympathy's complexities; De Waal, Darwin and Adam Smith.

    PubMed

    van der Weele, Cor

    2011-07-01

    Frans de Waal's view that empathy is at the basis of morality directly seems to build on Darwin, who considered sympathy as the crucial instinct. Yet when we look closer, their understanding of the central social instinct differs considerably. De Waal sees our deeply ingrained tendency to sympathize (or rather: empathize) with others as the good side of our morally dualistic nature. For Darwin, sympathizing was not the whole story of the "workings of sympathy"; the (selfish) need to receive sympathy played just as central a role in the complex roads from sympathy to morality. Darwin's understanding of sympathy stems from Adam Smith, who argued that the presence of morally impure motives should not be a reason for cynicism about morality. I suggest that De Waal's approach could benefit from a more thorough alignment with the analysis of the workings of sympathy in the work of Darwin and Adam Smith.

  7. Automatic Dynamic Aircraft Modeler (ADAM) for the Computer Program NASTRAN

    NASA Technical Reports Server (NTRS)

    Griffis, H.

    1985-01-01

    Large general purpose finite element programs require users to develop large quantities of input data. General purpose pre-processors are used to decrease the effort required to develop structural models. Further reduction of effort can be achieved by specific application pre-processors. Automatic Dynamic Aircraft Modeler (ADAM) is one such application specific pre-processor. General purpose pre-processors use points, lines and surfaces to describe geometric shapes. Specifying that ADAM is used only for aircraft structures allows generic structural sections, wing boxes and bodies, to be pre-defined. Hence with only gross dimensions, thicknesses, material properties and pre-defined boundary conditions a complete model of an aircraft can be created.

  8. Distal Limb Defects and Aplasia Cutis: Adams-Oliver Syndrome.

    PubMed

    Renfree, Kevin J; Dell, Paul C

    2016-07-01

    Adams-Oliver syndrome is a rare congenital condition that should be considered in persons with terminal transverse limb deficiencies and scalp defects (aplasia cutis congenita). Broad phenotypic variability exists in this condition. In its more severe forms, Adams-Oliver syndrome can involve the cardiovascular system, central nervous system, gastrointestinal tract, and genitourinary system and should require prompt evaluation by appropriate subspecialists. Extremity involvement is typically bilateral and asymmetrical, with lower extremities involved more than upper extremities. Brachydactyly is the most common limb defect, and severity ranges from hypoplastic nails to complete absence of the distal limb. The syndrome has been described as resulting from autosomal dominant and recessive modes of inheritance, but most cases are sporadic. No gene has been identified. Although the exact pathogenic mechanism is unknown, a common hypothesis is that a vascular disturbance occurs in watershed areas, such as cranial vertex and limbs, during fetal development.

  9. Application of the ADAMS program to deployable space truss structures

    NASA Technical Reports Server (NTRS)

    Calleson, R. E.

    1985-01-01

    The need for a computer program to perform kinematic and dynamic analyses of large truss structures while deploying from a packaged configuration in space led to the evaluation of several existing programs. ADAMS (automatic dynamic analysis of mechanical systems), a generalized program from performing the dynamic simulation of mechanical systems undergoing large displacements, is applied to two concepts of deployable space antenna units. One concept is a one cube folding unit of Martin Marietta's Box Truss Antenna and the other is a tetrahedral truss unit of a Tetrahedral Truss Antenna. Adequate evaluation of dynamic forces during member latch-up into the deployed configuration is not yet available from the present version of ADAMS since it is limited to the assembly of rigid bodies. Included is a method for estimating the maximum bending stress in a surface member at latch-up. Results include member displacement and velocity responses during extension and an example of member bending stresses at latch-up.

  10. The Role of Adams in Notch Signaling

    PubMed Central

    Groot, Arjan J.; Vooijs, Marc A.

    2014-01-01

    Regulated intramembrane proteolysis (RIP) is a highly conserved signaling paradigm whereby membrane-bound signaling proteins are cleaved in their transmembrane region and then released into the cytoplasm to act as signaling molecules. In most if not all cases intramembrane cleavage is preceded and regulated by a membrane proximal cleavage step called “ectodomain shedding”. Here we will review the role of ectodomain shedding in RIP of the NOTCH signaling pathway, a highly conserved cell-cell communication pathway that mediates cell fate decisions during development and in adult tissues. PMID:22399336

  11. An ADAM9 mutation in canine cone-rod dystrophy 3 establishes homology with human cone-rod dystrophy 9

    PubMed Central

    Goldstein, Orly; Mezey, Jason G.; Boyko, Adam R.; Gao, Chuan; Wang, Wei; Bustamante, Carlos D.; Anguish, Lynne J.; Jordan, Julie Ann; Pearce-Kelling, Susan E.; Aguirre, Gustavo D.

    2010-01-01

    Purpose To identify the causative mutation in a canine cone-rod dystrophy (crd3) that segregates as an adult onset disorder in the Glen of Imaal Terrier breed of dog. Methods Glen of Imaal Terriers were ascertained for crd3 phenotype by clinical ophthalmoscopic examination, and in selected cases by electroretinography. Blood samples from affected cases and non-affected controls were collected and used, after DNA extraction, to undertake a genome-wide association study using Affymetrix Version 2 Canine single nucleotide polymorphism chips and 250K Sty Assay protocol. Positional candidate gene analysis was undertaken for genes identified within the peak-association signal region. Retinal morphology of selected crd3-affected dogs was evaluated by light and electron microscopy. Results A peak association signal exceeding genome-wide significance was identified on canine chromosome 16. Evaluation of genes in this region suggested A Disintegrin And Metalloprotease domain, family member 9 (ADAM9), identified concurrently elsewhere as the cause of human cone-rod dystrophy 9 (CORD9), as a strong positional candidate for canine crd3. Sequence analysis identified a large genomic deletion (over 20 kb) that removed exons 15 and 16 from the ADAM9 transcript, introduced a premature stop, and would remove critical domains from the encoded protein. Light and electron microscopy established that, as in ADAM9 knockout mice, the primary lesion in crd3 appears to be a failure of the apical microvilli of the retinal pigment epithelium to appropriately invest photoreceptor outer segments. By electroretinography, retinal function appears normal in very young crd3-affected dogs, but by 15 months of age, cone dysfunction is present. Subsequently, both rod and cone function degenerate. Conclusions Identification of this ADAM9 deletion in crd3-affected dogs establishes this canine disease as orthologous to CORD9 in humans, and offers opportunities for further characterization of the disease

  12. A genetic toolkit for tagging intronic MiMIC containing genes

    PubMed Central

    Nagarkar-Jaiswal, Sonal; DeLuca, Steven Z; Lee, Pei-Tseng; Lin, Wen-Wen; Pan, Hongling; Zuo, Zhongyuan; Lv, Jiangxing; Spradling, Allan C; Bellen, Hugo J

    2015-01-01

    Previously, we described a large collection of Minos-Mediated Integration Cassettes (MiMICs) that contain two phiC31 recombinase target sites and allow the generation of a new exon that encodes a protein tag when the MiMIC is inserted in a codon intron (Nagarkar-Jaiswal et al., 2015). These modified genes permit numerous applications including assessment of protein expression pattern, identification of protein interaction partners by immunoprecipitation followed by mass spec, and reversible removal of the tagged protein in any tissue. At present, these conversions remain time and labor-intensive as they require embryos to be injected with plasmid DNA containing the exon tag. In this study, we describe a simple and reliable genetic strategy to tag genes/proteins that contain MiMIC insertions using an integrated exon encoding GFP flanked by FRT sequences. We document the efficiency and tag 60 mostly uncharacterized genes. DOI: http://dx.doi.org/10.7554/eLife.08469.001 PMID:26102525

  13. Evaluation of ADAM/1 model for advanced coal extraction concepts

    NASA Technical Reports Server (NTRS)

    Deshpande, G. K.; Gangal, M. D.

    1982-01-01

    Several existing computer programs for estimating life cycle cost of mining systems were evaluated. A commercially available program, ADAM/1 was found to be satisfactory in relation to the needs of the advanced coal extraction project. Two test cases were run to confirm the ability of the program to handle nonconventional mining equipment and procedures. The results were satisfactory. The model, therefore, is recommended to the project team for evaluation of their conceptual designs.

  14. Upregulated expression of ADAM12 is associated with progression of oral squamous cell carcinoma.

    PubMed

    Uehara, Erika; Shiiba, Masashi; Shinozuka, Keiji; Saito, Kengo; Kouzu, Yukinao; Koike, Hirofumi; Kasamatsu, Atsushi; Sakamoto, Yosuke; Ogawara, Katsunori; Uzawa, Katsuhiro; Tanzawa, Hideki

    2012-05-01

    ADAMs are a disintegrin and metalloproteinase family of membrane-associated metalloproteinases characterized by their multidomain structure, and have been reported to be associated with various malignant tumors. The aim of this study was to identify crucial members of the ADAM family in oral squamous cell carcinoma (OSCC), and to reveal their biological function and clinical significance. To clarify whether ADAM family genes are involved in OSCC, changes in the expression profile were investigated by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analysis and immunohistochemical analysis. Functional analysis was performed by comparing cellular proliferation of siADAM-transfected cell lines and parental cell lines. Real-time qRT-PCR analysis identified significantly upregulated expression of ADAM12 in OSCC-derived cell lines. This was validated in OSCC samples using real-time qRT-PCR and immuno-histochemical staining. ADAM12 expression was correlated with TNM classification; significantly greater expression of ADAM12 was observed in tumors with higher T classification and more advanced stages. Moreover, siADAM12-transfected cells showed both a suppressed proliferation rate and increased transforming growth factor (TGF)-β3 expression. Our data indicate that ADAM12 is overexpressed in OSCC and might accelerate cellular proliferation. Its function may be associated with TGF-β signaling. This study suggests that controlling the expression or activity of ADAM12 could be a useful strategy in the development of an effective cure for OSCC.

  15. Berberine inhibits PTP1B activity and mimics insulin action.

    PubMed

    Chen, Chunhua; Zhang, Yuebo; Huang, Cheng

    2010-07-02

    Type 2 diabetes patients show defects in insulin signal transduction that include lack of insulin receptor, decrease in insulin stimulated receptor tyrosine kinase activity and receptor-mediated phosphorylation of insulin receptor substrates (IRSs). A small molecule that could target insulin signaling would be of significant advantage in the treatment of diabetes. Berberine (BBR) has recently been shown to lower blood glucose levels and to improve insulin resistance in db/db mice partly through the activation of AMP-activated protein kinase (AMPK) signaling and induction of phosphorylation of insulin receptor (IR). However, the underlying mechanism remains largely unknown. Here we report that BBR mimics insulin action by increasing glucose uptake ability by 3T3-L1 adipocytes and L6 myocytes in an insulin-independent manner, inhibiting phosphatase activity of protein tyrosine phosphatase 1B (PTP1B), and increasing phosphorylation of IR, IRS1 and Akt in 3T3-L1 adipocytes. In diabetic mice, BBR lowers hyperglycemia and improves impaired glucose tolerance, but does not increase insulin release and synthesis. The results suggest that BBR represents a different class of anti-hyperglycemic agents.

  16. Synthetic human serum albumin Sudlow I binding site mimics.

    PubMed

    Karlsson, Björn C G; Rosengren, Annika M; Näslund, Inga; Andersson, Per Ola; Nicholls, Ian A

    2010-11-25

    Here, we report the design, synthesis, and characterization of molecularly imprinted polymer (MIP) derived mimics of the human serum albumin (HSA) Sudlow I site-the binding site for the anticoagulant warfarin. MIP design was based upon a combination of experimental ((1)H NMR) and computational (molecular dynamics) methods. Two MIPs and corresponding nonimprinted reference polymers were synthesized and characterized (scanning electron microscopy; nitrogen sorption; and Fourier transform infrared spectroscopy). MIP-ligand recognition was examined using radioligand binding studies, where the largest number of selective sites was found in a warfarin-imprinted methacrylic acid-ethylene dimethacrylate copolymer (MAA-MIP). The warfarin selectivity of this MIP was confirmed using radioligand displacement and zonal chromatographic studies. A direct comparison of MIP-warfarin binding characteristics with those of the HSA Sudlow I binding site was made, and similarities in site population (per gram polymer or protein) and affinities were observed. The warfarin selectivity of the MIP suggests its potential for use as a recognition element in a MIP-based warfarin sensor and even as a model to aid in understanding and steering blood-plasma protein-regulated transport processes or even for the development of warfarin sensors.

  17. Dr. Lytle Adams' incendiary "bat bomb" of World War II.

    PubMed

    Christen, Arden G; Christen, Joan A

    2004-11-01

    On December 7, 1941, a 60-year old dentist from Irwin, Pennsylvania, Dr. Lytle S. Adams, was driving home from a vacation at Carlsbad Caverns in New Mexico. Hours earlier, he had been gripped with amazement as he witnessed millions of bats exiting the caves of Carlsbad. Listening to his car radio on his return trip, he was shocked to hear that Japan had just attacked Pearl Harbor. Dr. Adams, outraged over this travesty, began to mentally construct a plan for U.S. retaliation. As his thoughts returned to the countless bats that had awed him, he formed a tentative plan: millions of these small, flying mammals could be connected to tiny, time-fused incendiary bombs, and then released to land on the flimsily constructed structures which dotted the cities of Japan. Within a few minutes, the bombs would explode and enflame the entire urban areas. He postulated that these immeasurable numbers of fires, spreading their devastation over such vast areas within Japanese cities would result in the enemy's speedy surrender. This article documents the futile efforts of Dr. Adams, his team and the U.S. government to develop and employ an effective, incendiary bat bomb. The recently developed atom bomb, a far more deadly weapon was used in its place.

  18. ADAM8 Enhances Osteoclast Precursor Fusion and Osteoclast Formation In Vitro and In Vivo

    PubMed Central

    Ishizuka, Hisako; García-Palacios, Verónica; Lu, Ganwei; Subler, Mark A; Zhang, Heju; Boykin, Christina S; Choi, Sun Jin; Zhao, Liena; Patrene, Kenneth; Galson, Deborah L; Blair, Harry C; Hadi, Tamer M; Windle, Jolene J; Kurihara, Noriyoshi; Roodman, G David

    2011-01-01

    ADAM8 expression is increased in the interface tissue around a loosened hip prosthesis and in the pannus and synovium of patients with rheumatoid arthritis, but its potential role in these processes is unclear. ADAM8 stimulates osteoclast (OCL) formation, but the effects of overexpression or loss of expression of ADAM8 in vivo and the mechanisms responsible for the effects of ADAM8 on osteoclastogenesis are unknown. Therefore, to determine the effects of modulating ADAM expression, we generated tartrate-resistant acid phosphatase (TRAP)–ADAM8 transgenic mice that overexpress ADAM8 in the OCL lineage and ADAM8 knockout (ADAM8 KO) mice. TRAP-ADAM8 mice developed osteopenia and had increased numbers of OCL precursors that formed hypermultinucleated OCLs with an increased bone-resorbing capacity per OCL. They also had an enhanced differentiation capacity, increased TRAF6 expression, and increased NF-κB, Erk, and Akt signaling compared with wild-type (WT) littermates. This increased bone-resorbing capacity per OCL was associated with increased levels of p-Pyk2 and p-Src activation. In contrast, ADAM8 KO mice did not display a bone phenotype in vivo, but unlike WT littermates, they did not increase RANKL production, OCL formation, or calvarial fibrosis in response to tumor necrosis factor α (TNF-α) in vivo. Since loss of ADAM8 does not inhibit basal bone remodeling but only blocks the enhanced OCL formation in response to TNF-α, these results suggest that ADAM8 may be an attractive therapeutic target for preventing bone destruction associated with inflammatory disease. © 2011 American Society for Bone and Mineral Research. PMID:20683884

  19. Design and characterization of ebolavirus GP prehairpin intermediate mimics as drug targets

    PubMed Central

    Clinton, Tracy R; Weinstock, Matthew T; Jacobsen, Michael T; Szabo-Fresnais, Nicolas; Pandya, Maya J; Whitby, Frank G; Herbert, Andrew S; Prugar, Laura I; McKinnon, Rena; Hill, Christopher P; Welch, Brett D; Dye, John M; Eckert, Debra M; Kay, Michael S

    2015-01-01

    Ebolaviruses are highly lethal filoviruses that cause hemorrhagic fever in humans and nonhuman primates. With no approved treatments or preventatives, the development of an anti-ebolavirus therapy to protect against natural infections and potential weaponization is an urgent global health need. Here, we describe the design, biophysical characterization, and validation of peptide mimics of the ebolavirus N-trimer, a highly conserved region of the GP2 fusion protein, to be used as targets to develop broad-spectrum inhibitors of ebolavirus entry. The N-trimer region of GP2 is 90% identical across all ebolavirus species and forms a critical part of the prehairpin intermediate that is exposed during viral entry. Specifically, we fused designed coiled coils to the N-trimer to present it as a soluble trimeric coiled coil as it appears during membrane fusion. Circular dichroism, sedimentation equilibrium, and X-ray crystallography analyses reveal the helical, trimeric structure of the designed N-trimer mimic targets. Surface plasmon resonance studies validate that the N-trimer mimic binds its native ligand, the C-peptide region of GP2. The longest N-trimer mimic also inhibits virus entry, thereby confirming binding of the C-peptide region during viral entry and the presence of a vulnerable prehairpin intermediate. Using phage display as a model system, we validate the suitability of the N-trimer mimics as drug screening targets. Finally, we describe the foundational work to use the N-trimer mimics as targets in mirror-image phage display, which will be used to identify d-peptide inhibitors of ebolavirus entry. PMID:25287718

  20. A Disintegrin and Metalloprotease (ADAM) 10 and ADAM17 Are Major Sheddases of T Cell Immunoglobulin and Mucin Domain 3 (Tim-3)*

    PubMed Central

    Möller-Hackbarth, Katja; Dewitz, Christin; Schweigert, Olga; Trad, Ahmad; Garbers, Christoph; Rose-John, Stefan; Scheller, Jürgen

    2013-01-01

    T cell immunoglobulin and mucin domain 3 (Tim-3) dampens the response of CD4+ and CD8+ effector T cells via induction of cell death and/or T cell exhaustion and enhances the ability of macrophages to clear pathogens via binding to galectin 9. Here we provide evidence that human Tim-3 is a target of A disintegrin and metalloprotease (ADAM)-mediated ectodomain shedding resulting in a soluble form of Tim-3. We identified ADAM10 and ADAM17 as major sheddases of Tim-3 as shown by ADAM-specific inhibitors and the ADAM10 pro-domain in HEK293 cells and ADAM10/ADAM17-deficient murine embryonic fibroblasts. PMA-induced shedding of Tim-3 was abrogated by deletion of amino acids Glu181–Asp190 of the stalk region and Tim-3 lacking the intracellular domain was not efficiently cleaved after PMA stimulation. Surprisingly, a single lysine residue within the intracellular domain rescues shedding of Tim-3. Shedding of endogenous Tim-3 was found in primary human CD14+ monocytes after PMA and ionomycin stimulation. Importantly, the recently described down-regulation of Tim-3 from Toll-like receptor-activated CD14+ monocytes was caused by ADAM10- and ADAM17-mediated shedding. Inhibition of Tim-3 shedding from lipopolysaccharide-induced monocytes did not influence lipopolysaccharide-induced TNFα and IL-6 but increases IL-12 expression. In summary, we describe Tim-3 as novel target for ADAM-mediated ectodomain shedding and suggest a role of Tim-3 shedding in TLR-mediated immune responses of CD14+ monocytes. PMID:24121505

  1. Exendin-4 promotes the membrane trafficking of the AMPA receptor GluR1 subunit and ADAM10 in the mouse neocortex.

    PubMed

    Ohtake, Nobuaki; Saito, Mieko; Eto, Masaaki; Seki, Kenjiro

    2014-05-01

    Glucagon-like peptide-1 (GLP-1) is a novel treatment modality for type 2 diabetes mellitus. However, GLP-1 has been suggested as a therapeutic target for Alzheimer's disease (AD). In rodent studies, GLP-1 reduces amyloid beta (Aβ) and facilitates synaptic plasticity. Therefore, in the present study, we investigated how GLP-1 facilitates synaptic plasticity and reduces the Aβ in vivo. Exendin-4, a GLP-1 receptor agonist that can cross the blood brain barrier, was subcutaneously administered to adult mice. We then extracted the total and the plasma membrane proteins from the mouse neocortex. Exendin-4 significantly increased the phosphorylation level of cAMP response element-binding protein (CREB). Consistently, the expression level of brain-derived neurotrophic factor (BDNF), a transcriptional target of CREB, was increased. Furthermore, exendin-4 increased the membrane protein level of the AMPA receptor GluR1 subunit and postsynaptic density protein-95 (PSD-95), whereas GluR2 was unaffected. These exendin-4-dependent increases in membrane GluR1, total PSD-95 and BDNF were abrogated by pretreatment with temozolomide (TMZ), a DNA-alkylating agent, indicating that these alterations were dependent on exendin-4-induced transcriptional activity. In addition, we found that exendin-4 increased the level of the α-C terminal fragment (α-CTF) of amyloid precursor protein (APP). Furthermore, protein levels of both mature and immature ADAM10, the α-secretase of APP in the plasma membrane, were increased, whereas the total mature and immature ADAM10 levels were unchanged. These exendin-4-dependent increases in α-CTF and ADAM10 were not affected by TMZ. These findings suggested that GLP-1 facilitates the GluR1 membrane insertion through CREB activation and increases α-secretase activity through ADAM10 membrane trafficking. Upregulation of GluR1 and ADAM10 at the plasma membrane were also observed in mice with intracerebroventricular administration of Aβ oligomer

  2. Molecular construction of HIV-gp120 discontinuous epitope mimics by assembly of cyclic peptides on an orthogonal alkyne functionalized TAC-scaffold.

    PubMed

    Werkhoven, P R; Elwakiel, M; Meuleman, T J; Quarles van Ufford, H C; Kruijtzer, J A W; Liskamp, R M J

    2016-01-14

    Mimics of discontinuous epitopes of for example bacterial or viral proteins may have considerable potential for the development of synthetic vaccines, especially if conserved epitopes can be mimicked. However, due to the structural complexity and size of discontinuous epitopes molecular construction of these mimics remains challeging. We present here a convergent route for the assembly of discontinuous epitope mimics by successive azide alkyne cycloaddition on an orthogonal alkyne functionalized scaffold. Here the synthesis of mimics of the HIV gp120 discontinuous epitope that interacts with the CD4 receptor is described. The resulting protein mimics are capable of inhibition of the gp120-CD4 interaction. The route is convergent, robust and should be applicable to other discontinuous epitopes.

  3. The inertia of sex: Henry Adams on family and the politics of unconditional love.

    PubMed

    Duff, Brian

    2010-01-01

    This article offers a reassessment of the contemporary relevance of the political thought of Henry Adams through a focus on his ideas about the relationship between family and politics. Adams' ideas have been dismissed by contemporary thinkers, like Richard Rorty, who rely on similar ideas about the role family should play in politics. The article traces the role of ideas about family as a unifying theme in Adams' history, fiction, and autobiography. It shows both why Adams believed familial sentiments, especially feminine and motherly love, were crucial to political unity, and why he thought these sentiments had become increasingly difficult to rely upon. In showing how Adams wrestled with the difficulties that emerge in putting familial sentiments to use for politics, the article suggests that Adams' ideas offer useful lessons for contemporary thinkers interested in the relationship between family and politics.

  4. A substrate-optimized electrophoretic mobility shift assay for ADAM12.

    PubMed

    Kotzsch, Alexander; Skovgaard, Tine; Buus, Uwe; Andersen, Simon; Devkota, Kanchan; Berthelsen, Jens

    2014-05-01

    ADAM12 belongs to the A disintegrin and metalloprotease (ADAM) family of secreted sheddases activating extracellular growth factors such as epidermal growth factor receptor (EGFR) ligands and tumor necrosis factor-alpha (TNF-α). ADAM proteases, most notably ADAM17 (TNF-α-converting enzyme), have long been investigated as pharmaceutical drug targets; however, due to lack of potency and in vivo side effects, none of the small-molecule inhibitors discovered so far has made it beyond clinical testing. Ongoing research on novel selective inhibitors of ADAMs requires reliable biochemical assays to validate molecular probes from large-scale screening efforts. Here we describe an electrophoretic mobility shift assay for ADAM12 based on the identification of an optimized peptide substrate that is characterized by excellent performance and reproducibility.

  5. The Enzyme-mimic Activity of Ferric Nano-Core Residing in Ferritin and Its Biosensing Applications

    SciTech Connect

    Tang, Zhiwen; Wu, Hong J.; Zhang, Youyu; Li, Zhaohui; Lin, Yuehe

    2011-11-15

    Ferritins are nano-scale globular protein cages encapsulating a ferric core. They widely exist in animals, plants, and microbes, playing indispensable roles in iron homeostasis. Interestingly, our study clearly demonstrates that ferritin has an enzyme-mimic activity derived from its ferric nano-core, but not the protein cage. Further study revealed that the mimic-enzyme activity of ferritin is more thermally stable and pH-tolerant compared with horseradish peroxidase. Considering the abundance of ferritin in numerous organisms, this finding may indicate a new role of ferritin in antioxidant and detoxification metabolisms. In addition, as a natural protein-caged nanoparticle with an enzyme-mimic activity, ferritin is readily conjugated with biomolecules to construct nano-biosensors, thus holds promising potential for facile and biocompatible labeling for sensitive and robust bioassays in biomedical applications.

  6. Adding a Lysine Mimic in the Design of Potent Inhibitors of Histone Lysine Methyltransferases

    SciTech Connect

    Chang, Yanqi; Ganesh, Thota; Horton, John R.; Spannhoff, Astrid; Liu, Jin; Sun, Aiming; Zhang, Xing; Bedford, Mark T.; Shinkai, Yoichi; Snyder, James P.; Cheng, Xiaodong

    2010-07-19

    Dynamic histone lysine methylation involves the activities of modifying enzymes (writers), enzymes removing modifications (erasers), and readers of the histone code. One common feature of these activities is the recognition of lysines in methylated and unmethylated states, whether they are substrates, reaction products, or binding partners. We applied the concept of adding a lysine mimic to an established inhibitor (BIX-01294) of histone H3 lysine 9 methyltransferases G9a and G9a-like protein by including a 5-aminopentyloxy moiety, which is inserted into the target lysine-binding channel and becomes methylated by G9a-like protein, albeit slowly. The compound enhances its potency in vitro and reduces cell toxicity in vivo. We suggest that adding a lysine or methyl-lysine mimic should be considered in the design of small-molecule inhibitors for other methyl-lysine writers, erasers, and readers.

  7. John Adams's Montesquieuean Moment: Enlightened Historicism in the Discourses on Davila.

    PubMed

    Green, Jonathan

    2016-01-01

    At the outset of the French Revolution John Adams penned a series of Discourses of Davila, philosophical ruminations on the sixteenth-century French Wars of Religion. Recent historians have read these Discourses in terms of Adams's Machiavellianism-his conviction that men's passions lead to violence, if unrestrained. But this reading overlooks the extent to which Adams intended his Discourses as a particular investigation into the French nation's character, and into whether the revolutionaries could lay claim to a native, French tradition of mixed constitutional government. Situating the Discourses vis-à-vis Adams's contemporaneous reading of Montesquieu, this article argues for an underappreciated historicist dimension to his thought.

  8. Chemotherapy-induced activation of ADAM-17: a novel mechanism of drug resistance in colorectal cancer

    PubMed Central

    Kyula, Joan N.; Van Schaeybroeck, Sandra; Doherty, Joanne; Fenning, Catherine S.; Longley, Daniel B.; Johnston, Patrick G.

    2010-01-01

    Purpose: We have shown previously that exposure to anticancer drugs can trigger the activation of human epidermal receptor (HER) survival pathways in colorectal cancer (CRC). In this study, we examined the role of ADAMs (a desintegrin and metalloproteases) and soluble growth factors in this acute drug resistance mechanism. Experimental design: In vitro and in vivo models of CRC were assessed. ADAM-17 activity was measured using a fluorometric assay. Ligand shedding was assessed by ELISA or Western blotting. Apoptosis was assessed by flow cytometry and Western blotting. Results: Chemotherapy (5-Fluorouracil, 5-FU) treatment resulted in acute increases in TGF-α-, amphiregulin- and heregulin-ligand shedding in vitro and in vivo that correlated with significantly increased ADAM-17 activity. siRNA-mediated silencing and pharmacological inhibition confirmed that ADAM-17 was the principal ADAM involved in this pro-survival response. Furthermore, overexpression of ADAM-17 significantly decreased the effect of chemotherapy on tumour growth and apoptosis. Mechanistically, we found that ADAM-17 not only regulated phosphorylation of HERs, but also increased the activity of a number of other growth factor receptors, such as IGF-1R and VEGFR. Conclusions: Chemotherapy acutely activates ADAM-17 which results in growth factor shedding, growth factor receptor activation and drug resistance in CRC tumours. Thus, pharmacological inhibition of ADAM-17 in conjunction with chemotherapy may have therapeutic potential for the treatment of CRC. PMID:20570921

  9. ADAM17 cleaves CD16b (FcγRIIIb) in human neutrophils

    PubMed Central

    Wang, Yue; Wu, Jianming; Newton, Robert; Bahaie, Nooshin S.; Long, Chunmei; Walcheck, Bruce

    2012-01-01

    CD16b (FcγRIIIb) is exclusively expressed by human neutrophils and binds IgG in immune complexes. Cell surface CD16b undergoes efficient ectodomain shedding upon neutrophil activation and apoptosis. Indeed, soluble CD16b is present at high levels in the plasma of healthy individuals, which appears to be maintained by the daily turnover of apoptotic neutrophils. At this time, the principal protease responsible for CD16b shedding is not known. We show that CD16b plasma levels were significantly decreased in patients administered a selective inhibitor targeting the metalloproteases ADAM10 and ADAM17. Additional analysis with inhibitors selective for ADAM10 or ADAM17 revealed that only inhibition of ADAM17 significantly blocked the cleavage of CD16b following neutrophil activation and apoptosis. CD16b shedding by ADAM17 was further demonstrated using a unique ADAM17 function-blocking mAb and a cell-based ADAM17 reconstitution assay. Unlike human CD16, however, mouse CD16 did not undergo efficient ectodomain shedding upon neutrophil stimulation or apoptosis, indicating that this mechanism cannot be modeled in normal mice. Taken together, our findings are the first to directly demonstrate that ADAM17 cleaves CD16 in human leukocytes. PMID:23228566

  10. ADAM19: A Novel Target for Metabolic Syndrome in Humans and Mice

    PubMed Central

    Weerasekera, Lakshini; Rudnicka, Caroline; Sang, Qing-Xiang; Johnson, Matthew P.; Moses, Eric K.; Göring, Harald H. H.; Blangero, John; Hricova, Jana; Schlaich, Markus

    2017-01-01

    Obesity is one of the most prevalent metabolic diseases in the Western world and correlates directly with insulin resistance, which may ultimately culminate in type 2 diabetes (T2D). We sought to ascertain whether the human metalloproteinase A Disintegrin and Metalloproteinase 19 (ADAM19) correlates with parameters of the metabolic syndrome in humans and mice. To determine the potential novel role of ADAM19 in the metabolic syndrome, we first conducted microarray studies on peripheral blood mononuclear cells from a well-characterised human cohort. Secondly, we examined the expression of ADAM19 in liver and gonadal white adipose tissue using an in vivo diet induced obesity mouse model. Finally, we investigated the effect of neutralising ADAM19 on diet induced weight gain, insulin resistance in vivo, and liver TNF-α levels. Significantly, we show that, in humans, ADAM19 strongly correlates with parameters of the metabolic syndrome, particularly BMI, relative fat, HOMA-IR, and triglycerides. Furthermore, we identified that ADAM19 expression was markedly increased in the liver and gonadal white adipose tissue of obese and T2D mice. Excitingly, we demonstrate in our diet induced obesity mouse model that neutralising ADAM19 therapy results in weight loss, improves insulin sensitivity, and reduces liver TNF-α levels. Our novel data suggest that ADAM19 is pro-obesogenic and enhances insulin resistance. Therefore, neutralisation of ADAM19 may be a potential therapeutic approach to treat obesity and T2D. PMID:28265178

  11. Molecular characterization and expression analysis of ADAM12 during chicken embryonic development.

    PubMed

    Lin, Juntang; Luo, Jiankai; Redies, Christoph

    2010-12-01

    ADAM12 is a member of the disintegrin and metalloprotease (ADAM) family of molecules, which consist of multiple domains. ADAM12 is involved in different physiological and pathological processes. In the present study, full-length sequences of two chicken ADAM12 isoforms were cloned and identified by reverse transcription-polymerase chain reaction (RT-PCR), rapid amplification of cDNA ends methods and bioinformatics analysis. The long isoform consists of all domains characteristic for ADAMs and is strongly expressed in different tissues, whereas the short isoform lacks large parts of the metalloprotease and disintegrin domains and is only expressed weakly. Results from semi-quantitative RT-PCR show that the complete ADAM12 is stably expressed throughout chicken embryonic development, while the short isoform is only regionally detectable in the lung and brain. Results from in situ hybridization show that chicken ADAM12 is expressed exclusively in tissues and organs derived from the neural tube, the neural crest or the mesoderm, with a highly regulated spatiotemporal expression pattern. Our data confirm and extend studies of ADAM12 in other species, and suggest that ADAM12 may play a role in the development of several organs, including the formation of feather buds.

  12. Recent eruptions of Mount Adams, Washington Cascades, USA

    USGS Publications Warehouse

    Hildreth, Wes; Fierstein, Judy

    1997-01-01

    The postglacial eruption rate for the Mount Adams volcanic field is ∼0.1 km3/k.y., four to seven times smaller than the average rate for the past 520 k.y. Ten vents have been active since the last main deglaciation ∼15 ka. Seven high flank vents (at 2100-2600 m) and the central summit vent of the 3742-m stratocone produced varied andesites, and two peripheral vents (at 2100 and 1200 m) produced mildly alkalic basalt. Eruptive ages of most of these units are bracketed with respect to regional tephra layers from Mount Mazama and Mount St. Helens. The basaltic lavas and scoria cones north and south of Mount Adams and a 13-km-long andesitic lava flow on its east flank are of early postglacial age. The three most extensive andesitic lava-flow complexes were emplaced in the mid-Holocene (7-4 ka). Ages of three smaller Holocene andesite units are less well constrained. A phreatomagmatic ejecta cone and associated andesite lavas that together cap the summit may be of latest Pleistocene age. but a thin layer of mid-Holocene tephra appears to have erupted there as well. An alpine-meadow section on the southeast flank contains 24 locally derived Holocene andesitic ash layers intercalated with several silicic tephras from Mazama and St. Helens. Microprobe analyses of phenocrysts from the ash layers and postglacial lavas suggest a few correlations and refine some age constraints. Approximately 6 ka, a 0.07-km3 debris avalanche from the southwest face of Mount Adams gen-erated a clay-rich debris flow that devastated >30 km2 south of the volcano. A gravitationally metastable 2-to 3-km3 reservoir of hydrothermally altered fragmental andesite remains on the ice-capped summit and, towering 3 km above the surrounding lowlands, represents a greater hazard than an eruptive recurrence in the style of the last 15 k.y.

  13. Chlamydomonas reinhardtii Secretes Compounds That Mimic Bacterial Signals and Interfere with Quorum Sensing Regulation in Bacteria1

    PubMed Central

    Teplitski, Max; Chen, Hancai; Rajamani, Sathish; Gao, Mengsheng; Merighi, Massimo; Sayre, Richard T.; Robinson, Jayne B.; Rolfe, Barry G.; Bauer, Wolfgang D.

    2004-01-01

    The unicellular soil-freshwater alga Chlamydomonas reinhardtii was found to secrete substances that mimic the activity of the N-acyl-l-homoserine lactone (AHL) signal molecules used by many bacteria for quorum sensing regulation of gene expression. More than a dozen chemically separable but unidentified substances capable of specifically stimulating the LasR or CepR but not the LuxR, AhyR, or CviR AHL bacterial quorum sensing reporter strains were detected in ethyl acetate extracts of C. reinhardtii culture filtrates. Colonies of C. reinhardtii and Chlorella spp. stimulated quorum sensing-dependent luminescence in Vibrio harveyi, indicating that these algae may produce compounds that affect the AI-2 furanosyl borate diester-mediated quorum sensing system of Vibrio spp. Treatment of the soil bacterium Sinorhizobium meliloti with a partially purified LasR mimic from C. reinhardtii affected the accumulation of 16 of the 25 proteins that were altered in response to the bacterium's own AHL signals, providing evidence that the algal mimic affected quorum sensing-regulated functions in this wild-type bacterium. Peptide mass fingerprinting identified 32 proteins affected by the bacterium's AHLs or the purified algal mimic, including GroEL chaperonins, the nitrogen regulatory protein PII, and a GTP-binding protein. The algal mimic was able to cancel the stimulatory effects of bacterial AHLs on the accumulation of seven of these proteins, providing evidence that the secretion of AHL mimics by the alga could be effective in disruption of quorum sensing in naturally encountered bacteria. PMID:14671013

  14. Lance–Adams syndrome: A special case of a mother

    PubMed Central

    Nigam, Gaurav Bhaskar; Babu, Sachin Suresh; Peter, C. Sudhir; Peter, C. Shobhna

    2016-01-01

    Predicting the neurological outcome in survivors of cardiorespiratory arrest is difficult. A distinction has been made between acute and chronic posthypoxic myoclonus, called myoclonic status epilepticus and Lance–Adams syndrome (LAS), respectively, with the acute condition carrying a bad prognosis. Here, we report a case of a 37-year-old female who developed seizures after a successful cardiopulmonary resuscitation. The available literature on such cases is very rare and has generally mentioned a poor outcome. However, our patient was successfully managed and showed clinical features of LAS. Thus, making an early diagnosis and proper management of hypoxic brain insults is positively related to improving the patient's functional outcome. PMID:27688633

  15. Simulation of Naval Guns' Breechblock System Dynamics Based on ADAMS

    NASA Astrophysics Data System (ADS)

    Tan, Bo; Liu, Hui-Min; Liu, Kai

    In order to study the dynamical characteristics of the breechblock system during gun firing, a virtual prototype model was established based on ADAMS, in which motion and force transmission among mechanisms are realized by collision. By simulation, kinematics and dynamics properties of main components are obtained, and the relationships between the motion of breechblock and the position of breechblock opening plate are analyzed. According to the simulation results, the collision among the breechblock opening plate and the roller is discontinuous, which may make the breechblock system fail to hitch the breechblock reliably. And within allowable scope of the structure, the breechblock opening template should be installed near the upside as much as possible.

  16. Applying the Adams influence model in nurse executive practice.

    PubMed

    Adams, Jeffrey M; Erickson, Jeanette Ives

    2011-04-01

    The ability to influence others is a required competency for nurse executives trying to achieve positive patient/organizational outcomes. The Adams Influence Model (AIM) is a framework for understanding the factors, attributes, and process of influence. The AIM is grounded in nursing and organizational literature and provides nurse leaders with a road map for developing an effective strategy to achieve influence with individuals and/or groups. The authors describe the AIM and present a case study illustrating its application by a chief nurse executive.

  17. The "delivery" of Adam: a medical interpretation of Michelangelo.

    PubMed

    Di Bella, Stefano; Taglietti, Fabrizio; Iacobuzio, Andrea; Johnson, Emma; Baiocchini, Andrea; Petrosillo, Nicola

    2015-04-01

    This article describes what we believe to be the key to interpreting the concept represented by Michelangelo's painting the Creation of Adam. This fresco, one of his most famous masterpieces, is situated in the heart of the Sistine Chapel and is viewed by millions of people every year. A man of many talents, Michelangelo's proficiency in anatomical dissection is reflected in his artwork. As such, analyses of hidden meanings in this fresco have been ascribed, including the concept of the "Brain-God." However, we see a postpartum uterus and adjacent anatomy, justifying our interpretation that Michelangelo was depicting something far more fundamental: the birth of mankind.

  18. MOUNT ADAMS WILDERNESS AND CONTIGUOUS ROADLESS AREAS, WASHINGTON.

    USGS Publications Warehouse

    Hildreth, Wes; Miller, M.

    1984-01-01

    There is little likelihood for the occurrence of metallic mineral or energy resources based on a mineral survey in 1981-82 in the Mount Adams Wilderness and contiguous roadless areas, Washington. No mining claims exist in the study area, which is almost entirely a young andesitic stratovolcano. There is no indication of a shallow magma reservoir capable of supporting a convective geothermal system. Drilling in the lowland periphery of the volcano might be technically difficult, but 150 degree -200 degree F waters suitable for space heating would not be unexpected at depths of 5000-6000 ft.

  19. ADAM10 Is the Major Sheddase Responsible for the Release of Membrane-associated Meprin A*

    PubMed Central

    Herzog, Christian; Haun, Randy S.; Ludwig, Andreas; Shah, Sudhir V.; Kaushal, Gur P.

    2014-01-01

    Meprin A, composed of α and β subunits, is a membrane-bound metalloproteinase in renal proximal tubules. Meprin A plays an important role in tubular epithelial cell injury during acute kidney injury (AKI). The present study demonstrated that during ischemia-reperfusion-induced AKI, meprin A was shed from proximal tubule membranes, as evident from its redistribution toward the basolateral side, proteolytic processing in the membranes, and excretion in the urine. To identify the proteolytic enzyme responsible for shedding of meprin A, we generated stable HEK cell lines expressing meprin β alone and both meprin α and meprin β for the expression of meprin A. Phorbol 12-myristate 13-acetate and ionomycin stimulated ectodomain shedding of meprin β and meprin A. Among the inhibitors of various proteases, the broad spectrum inhibitor of the ADAM family of proteases, tumor necrosis factor-α protease inhibitor (TAPI-1), was most effective in preventing constitutive, phorbol 12-myristate 13-acetate-, and ionomycin-stimulated shedding of meprin β and meprin A in the medium of both transfectants. The use of differential inhibitors for ADAM10 and ADAM17 indicated that ADAM10 inhibition is sufficient to block shedding. In agreement with these results, small interfering RNA to ADAM10 but not to ADAM9 or ADAM17 inhibited meprin β and meprin A shedding. Furthermore, overexpression of ADAM10 resulted in enhanced shedding of meprin β from both transfectants. Our studies demonstrate that ADAM10 is the major ADAM metalloproteinase responsible for the constitutive and stimulated shedding of meprin β and meprin A. These studies further suggest that inhibiting ADAM 10 activity could be of therapeutic benefit in AKI. PMID:24662289

  20. Surgically Confirmed Intra- and Extratesticular Hematoma Clinically Mimicing Epididymo-Orchitis and Radiologically Mimicing Traumatic Torsion

    PubMed Central

    Akay, Sinan; Kaygisiz, Mustafa; Oztas, Muharrem; Turgut, Mustafa Suphi

    2015-01-01

    Summary Background Scrotal blunt trauma may result in injuries, such as testicular rupture, dislocation, torsion, hematoma, spermatic cord injury or contusion, and epididymal, scrotal, and urethral injuries. Ultrasonography (US) has a crucial role in the evaluation of those kinds of pathologies. Early diagnosis of testicular rupture may lead to the salvaging of the testicle by prompt surgical exploration within 72 h. Case Report A 21-year-old male with right scrotal swelling and pain complaints was admitted to another hospital one month ago. Epididymo-orchitis was diagnosed and the patient was given medical treatment. The patient was admitted to our emergency service with ongoing complaints. The patient stated that the pain and swelling suddenly developed after prolonged marching. On US, a large hematoma was detected between the leaves of the tunica vaginalis, and rupture from the lower pole was diagnosed. On color Doppler US, no vascularity was observed in the heterogeneous testicular parenchyma. Traumatic torsion was primarily suggested. Intraoperatively, an extratesticular hematoma, hematocele, and rupture were confirmed but torsion was not found. Because the hematoma entirely replaced the normal parenchyma, orchiectomy was performed. Conclusions Testicular rupture may occur even after moderate sportive action such as prolonged marching. If any delay occurs in diagnosis and/or operation, the coagulum may replace the entire parenchyma. We think that US and clinical findings may sometimes mislead the physicians and cause misdiagnoses, such as inflammation or torsion. In this paper, we present a complex delayed diagnosed example case of testicular rupture clinically mimicing epididymo-orchitis and radiologically mimicing traumatic testicular torsion. PMID:26600877

  1. Phenotypic plasticity confers multiple fitness benefits to a mimic.

    PubMed

    Cortesi, Fabio; Feeney, William E; Ferrari, Maud C O; Waldie, Peter A; Phillips, Genevieve A C; McClure, Eva C; Sköld, Helen N; Salzburger, Walter; Marshall, N Justin; Cheney, Karen L

    2015-03-30

    Animal communication is often deceptive; however, such dishonesty can become ineffective if it is used too often, is used out of context, or is too easy to detect [1-3]. Mimicry is a common form of deception, and most mimics gain the greatest fitness benefits when they are rare compared to their models [3, 4]. If mimics are encountered too frequently or if their model is absent, avoidance learning of noxious models is disrupted (Batesian mimicry [3]), or receivers become more vigilant and learn to avoid perilous mimics (aggressive mimicry [4]). Mimics can moderate this selective constraint by imperfectly resembling multiple models [5], through polymorphisms [6], or by opportunistically deploying mimetic signals [1, 7]. Here we uncover a novel mechanism to escape the constraints of deceptive signaling: phenotypic plasticity allows mimics to deceive targets using multiple guises. Using a combination of behavioral, cell histological, and molecular methods, we show that a coral reef fish, the dusky dottyback (Pseudochromis fuscus), flexibly adapts its body coloration to mimic differently colored reef fishes and in doing so gains multiple fitness benefits. We find that by matching the color of other reef fish, dottybacks increase their success of predation upon juvenile fish prey and are therefore able to deceive their victims by resembling multiple models. Furthermore, we demonstrate that changing color also increases habitat-associated crypsis that decreases the risk of being detected by predators. Hence, when mimics and models share common selective pressures, flexible imitation of models might inherently confer secondary benefits to mimics. Our results show that phenotypic plasticity can act as a mechanism to ease constraints that are typically associated with deception. VIDEO ABSTRACT.

  2. Traumatic aortic injury: CT findings, mimics, and therapeutic options

    PubMed Central

    Lantz, Eric J.; Johnson, C. Michael; Young, Philip M.

    2014-01-01

    Objective Traumatic aortic injury (TAI) is rare, but frequently lethal. However, with prompt diagnosis, patients can undergo life-saving open or endovascular repair. Unfortunately, because these injuries are relatively rare, subtle forms of these injuries may be missed, and normal variants may mimic TAI leading to misdiagnosis. Conclusions We will discuss computed tomography findings of typical injury patterns of traumatic aortic injuries as well as treatment options, diagnostic pitfalls and injury mimics. These are highlighted with clinical case examples. PMID:25009793

  3. The futility of utility: how market dynamics marginalize Adam Smith

    NASA Astrophysics Data System (ADS)

    McCauley, Joseph L.

    2000-10-01

    Economic theorizing is based on the postulated, nonempiric notion of utility. Economists assume that prices, dynamics, and market equilibria are supposed to be derived from utility. The results are supposed to represent mathematically the stabilizing action of Adam Smith's invisible hand. In deterministic excess demand dynamics I show the following. A utility function generally does not exist mathematically due to nonintegrable dynamics when production/investment are accounted for, resolving Mirowski's thesis. Price as a function of demand does not exist mathematically either. All equilibria are unstable. I then explain how deterministic chaos can be distinguished from random noise at short times. In the generalization to liquid markets and finance theory described by stochastic excess demand dynamics, I also show the following. Market price distributions cannot be rescaled to describe price movements as ‘equilibrium’ fluctuations about a systematic drift in price. Utility maximization does not describe equilibrium. Maximization of the Gibbs entropy of the observed price distribution of an asset would describe equilibrium, if equilibrium could be achieved, but equilibrium does not describe real, liquid markets (stocks, bonds, foreign exchange). There are three inconsistent definitions of equilibrium used in economics and finance, only one of which is correct. Prices in unregulated free markets are unstable against both noise and rising or falling expectations: Adam Smith's stabilizing invisible hand does not exist, either in mathematical models of liquid market data, or in real market data.

  4. Co-mimics have a mutualistic relationship despite unequal defences.

    PubMed

    Rowland, Hannah M; Ihalainen, Eira; Lindström, Leena; Mappes, Johanna; Speed, Michael P

    2007-07-05

    In the first clear mathematical treatment of natural selection, Müller proposed that a shared warning signal (mimicry) would benefit defended prey species by sharing out the per capita mortality incurred during predator education. Although mimicry is a mainstay of adaptationist thinking, there has been repeated debate on whether there is a mutualistic or a parasitic relationship between unequally defended co-mimic species. Here we show that the relationship between unequally defended species is mutualistic. We examined this in a 'novel world' of artificial prey with wild predators (great tit, Parus major). We kept the abundance of a highly defended prey ('model') constant and increased the density of a moderately defended prey ('defended mimic') of either perfect or imperfect mimetic resemblance to the model. Both model and defended mimic showed a net benefit from a density-dependent decrease in their per capita mortality. Even when the effect of dilution through density was controlled for, defended mimics did not induce additional attacks on the model, but we found selection for accurate signal mimicry. In comparison, the addition of fully edible (batesian) mimics did increase additional attacks on the model, but as a result of dilution this resulted in no overall increase in per capita mortality. By ignoring the effects of density, current theories may have overestimated the parasitic costs imposed by less defended mimics on highly defended models.

  5. DEVELOPMENT OF THE HUMAN LUNG MEASURED BY AEROSOL-DERIVED AIRWAY MORPHEMETRY (ADAM).

    EPA Science Inventory

    We measured, in vivo, the airspace calibers of the small airways and alveoli by ADAM in the lungs of children of ages 6 to 18 years and adults aged 18 to 80 years. ADAM utilizes the gravitational settling time of inhaled monodisperse particles to infer the vertical distance to th...

  6. 77 FR 75207 - The Adams Express Company and Petroleum & Resources Corporation; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-19

    ... COMMISSION The Adams Express Company and Petroleum & Resources Corporation; Notice of Application December 13... and Petroleum & Resources Corporation (the ``Funds''). DATES: Filing Dates: The application was filed..., 2012, The Adams Express Company held approximately 8.5% of the outstanding shares of...

  7. The disintegrin/metalloproteinase Adam10 is essential for epidermal integrity and Notch-mediated signaling.

    PubMed

    Weber, Silvio; Niessen, Michaela T; Prox, Johannes; Lüllmann-Rauch, Renate; Schmitz, Annika; Schwanbeck, Ralf; Blobel, Carl P; Jorissen, Ellen; de Strooper, Bart; Niessen, Carien M; Saftig, Paul

    2011-02-01

    The disintegrin and metalloproteinase Adam10 has been implicated in the regulation of key signaling pathways that determine skin morphogenesis and homeostasis. To address the in vivo relevance of Adam10 in the epidermis, we have selectively disrupted Adam10 during skin morphogenesis and in adult skin. K14-Cre driven epidermal Adam10 deletion leads to perinatal lethality, barrier impairment and absence of sebaceous glands. A reduction of spinous layers, not associated with differences in either proliferation or apoptosis, indicates that loss of Adam10 triggers a premature differentiation of spinous keratinocytes. The few surviving K14-Adam10-deleted mice and mice in which Adam10 was deleted postnatally showed loss of hair, malformed vibrissae, epidermal hyperproliferation, cyst formation, thymic atrophy and upregulation of the cytokine thymic stromal lymphopoetin (TSLP), thus indicating non cell-autonomous multi-organ disease resulting from a compromised barrier. Together, these phenotypes closely resemble skin specific Notch pathway loss-of-function phenotypes. Notch processing is indeed strongly reduced resulting in decreased levels of Notch intracellular domain fragment and functional Notch signaling. The data identify Adam10 as the major Site-2 processing enzyme for Notch in the epidermis in vivo, and thus as a central regulator of skin development and maintenance.

  8. ADAM-17 regulates endothelial cell morphology, proliferation, and in vitro angiogenesis

    SciTech Connect

    Goeoz, Pal Goeoz, Monika; Baldys, Aleksander; Hoffman, Stanley

    2009-02-27

    Modulation of angiogenesis is a promising approach for treating a wide variety of human diseases including ischemic heart disease and cancer. In this study, we show that ADAM-17 is an important regulator of several key steps during angiogenesis. Knocking down ADAM-17 expression using lentivirus-delivered siRNA in HUVECs inhibited cell proliferation and the ability of cells to form close contact in two-dimensional cultures. Similarly, ADAM-17 depletion inhibited the ability of HUVECs to form capillary-like networks on top of three-dimensional Matrigel as well as in co-culture with fibroblasts within a three-dimensional scaffold. In mechanistic studies, both baseline and VEGF-induced MMP-2 activation and Matrigel invasion were inhibited by ADAM-17 depletion. Based on our findings we propose that ADAM-17 is part of a novel pro-angiogenic pathway leading to MMP-2 activation and vessel formation.

  9. The role of CXCL16 and its processing metalloproteinases ADAM10 and ADAM17 in the proliferation and migration of human mesangial cells

    SciTech Connect

    Schramme, Anja; Abdel-Bakky, Mohamed Sadek; Kaempfer-Kolb, Nicole; Pfeilschifter, Josef

    2008-05-30

    In this study, we analyzed the regulation and functional role of CXCL16 in human mesangial cells (hMCs). We can show, that CXCL16 is constitutively expressed in hMCs and is further up-regulated by cytokine mix (IFN{gamma}, TNF{alpha}, and IL1{beta}). The constitutive release of CXCL16 from hMCs was rapidly induced by the stimulation with cytokines. We identified ADAM10 and ADAM17 as being responsible for the cytokine-induced shedding of CXCL16. Notably, targeting ADAM10 and ADAM17 in hMCs decreased the chemotaxis of T-Jurkat cells, whereas the inhibition of CXCL16 had no significant influence. This suggests that both proteases are important players in the recruitment of immune cells into the glomerulus, but other substrates than CXCL16 are involved in this process. Finally, we could show that the inhibition of CXCL16, ADAM10, and ADAM17 led to a strong reduction of cell proliferation and migration of hMCs. This finding could be important to develop novel diagnostic and therapeutic strategies to treat mesangial proliferative kidney diseases.

  10. TLR4-mediated galectin-1 production triggers epithelial-mesenchymal transition in colon cancer cells through ADAM10- and ADAM17-associated lactate production.

    PubMed

    Park, Ga Bin; Kim, Daejin

    2017-01-01

    Toll-like receptor 4 (TLR4) activation is a key contributor to the carcinogenesis of colon cancer. Overexpression of galectin-1 (Gal-1) also correlates with increased invasive activity of colorectal cancer. Lactate production is a critical predictive factor of risk of metastasis, but the functional relationship between intracellular lactate and Gal-1 expression in TLR4-activated colon cancer remains unknown. In this study, we investigated the underlying mechanism and role of Gal-1 in metastasis and invasion of colorectal cancer (CRC) cells after TLR4 stimulation. Exposure to the TLR4 ligand lipopolysaccharide (LPS) increased expression of Gal-1, induced EMT-related cytokines, triggered the activation of glycolysis-related enzymes, and promoted lactate production. Gene silencing of TLR4 and Gal-1 in CRC cells inhibited lactate-mediated epithelial-mesenchymal transition (EMT) after TLR4 stimulation. Gal-1-mediated activation of a disintegrin and metalloproteinase 10 (ADAM10) and ADAM 17 increased the invasion activity and expression of mesenchymal characteristics in LPS-activated CRC cells. Conversely, inhibition of ADAM10 or ADAM17 effectively blocked the generation of lactate and the migration capacity of LPS-treated CRC cells. Thus, the TLR4/Gal-1 signaling pathway regulates lactate-mediated EMT processes through the activation of ADAM10 and ADAM17 in CRC cells.

  11. Synthetic Polypeptide Mimics of Marine Adhesives.

    PubMed

    Yu; Deming

    1998-07-28

    Water soluble copolypeptides containing l-dihydroxyphenylalanine (DOPA) and l-lysine were prepared by ring-opening polymerization of alpha-amino acid N-carboxyanhydride (NCA) monomers. We have prepared a range of different copolymers to probe the effects of functional group composition on adhesive and cross-linking behavior. Aqueous solutions of these copolymers, when mixed with a suitable oxidizing agent (e.g., O2, mushroom tyrosinase, Fe3+, H2O2, or IO4-), formed cross-linked networks that were found to form moisture-resistant adhesive bonds to a variety of substrates (e.g., aluminum, steel, glass, and plastics). It was found that successful adhesive formation was dependent on oxidation conditions, with chemical oxidants giving the best results. Optimized systems were found to form adhesive bonds that rival in strength those formed by natural marine adhesive proteins. Our synthetic systems are readily prepared in large quantities and require no enzymes or other biological components.

  12. Cell-sized liposomes that mimic cell motility and the cell cortex.

    PubMed

    Lemière, Joël; Carvalho, Kevin; Sykes, Cécile

    2015-01-01

    Cells move and change shape by dynamically reorganizing their cytoskeleton next to the plasma membrane. In particular, actin assembly generates forces and stresses that deform the cell membrane. Cell-sized liposomes are designed to mimic this function. The activation of actin polymerization at their membrane is able to push the membrane forward, thus reproducing the mechanism of lamellipodium extension at the cell front. Moreover, the cell cortex, a submicrometer-thick actin shell right beneath the cell membrane can be reproduced; it contributes to cell tension with the action of molecular motors. We will describe experimental methods to prepare liposomes that mimic the inside geometry of a cell, and that reproduce actin-based propulsion of the liposome using an outside geometry. Such systems allow to study how actin-related proteins control and affect actin cortex assembly and can produce forces that drive cell shape changes.

  13. Cyclic AMP Mimics the Anti-ageing Effects of Calorie Restriction by Up-Regulating Sirtuin.

    PubMed

    Wang, Zhuoran; Zhang, Lu; Liang, Yaru; Zhang, Chi; Xu, Zhiyu; Zhang, Lang; Fuji, Ryosuke; Mu, Wei; Li, Liyuan; Jiang, Junjun; Ju, Yong; Wang, Zhao

    2015-07-08

    Cyclic adenosine monophosphate (cAMP) plays an important role in many biological processes as a second messenger, and cAMP treatment has been reported to extend the lifespan of wild-type Drosophila melanogaster. Our study showed that exogenous cAMP improved ageing-related phenotypes by increasing the protein level of Sirtuins, which prevented metabolic disorders to mimic the effect of calorie restriction. Experiments in vitro showed that cAMP directly bound to SIRT1 and SIRT3 and consequently increased their activity. These findings suggest that cAMP slows the ageing process and is a good candidate to mimic calorie restriction. Our research provides a promising therapeutic strategy to target metabolic disorder-induced ageing-related diseases.

  14. A-Disintegrin and Metalloproteinase (ADAM) 17 Enzymatically Degrades Interferon-gamma

    PubMed Central

    Kanzaki, Hiroyuki; Shinohara, Fumiaki; Suzuki, Maiko; Wada, Satoshi; Miyamoto, Yutaka; Yamaguchi, Yuuki; Katsumata, Yuta; Makihira, Seicho; Kawai, Toshi; Taubman, Martin A.; Nakamura, Yoshiki

    2016-01-01

    Interferon-gamma (IFN-γ) is a pleiotropic cytokine that exerts anti-tumor and anti-osteoclastogenic effects. Although transcriptional and post-transcriptional regulation of IFN-γ is well understood, subsequent modifications of secreted IFN-γ are not fully elucidated. Previous research indicates that some cancer cells escape immune surveillance and metastasize into bone tissue by inducing osteoclastic bone resorption. Peptidases of the a-disintegrin and metalloproteinase (ADAM) family are implicated in cancer cell proliferation and tumor progression. We hypothesized that the ADAM enzymes expressed by cancer cells degrades IFN-γ and attenuates IFN-γ-mediated anti-tumorigenic and anti-osteoclastogenic effects. Recombinant ADAM17 degraded IFN-γ into small fragments. The addition of ADAM17 to the culture supernatant of stimulated mouse splenocytes decreased IFN-γ concentration. However, ADAM17 inhibition in the stimulated mouse T-cells prevented IFN-γ degradation. ADAM17-expressing human breast cancer cell lines MCF-7 and MDA-MB-453 also degraded recombinant IFN-γ, but this was attenuated by ADAM17 inhibition. Degraded IFN-γ lost the functionality including the inhibititory effect on osteoclastogenesis. This is the first study to demonstrate the extracellular proteolytic degradation of IFN-γ by ADAM17. These results suggest that ADAM17-mediated degradation of IFN-γ may block the anti-tumorigenic and anti-osteoclastogenic effects of IFN-γ. ADAM17 inhibition may be useful for the treatment of attenuated cancer immune surveillance and/or bone metastases. PMID:27573075

  15. Differential expression and regulation of ADAM17 and TIMP3 in acute inflamed intestinal epithelia.

    PubMed

    Cesaro, Annabelle; Abakar-Mahamat, Abakar; Brest, Patrick; Lassalle, Sandra; Selva, Eric; Filippi, Jérôme; Hébuterne, Xavier; Hugot, Jean-Pierre; Doglio, Alain; Galland, Franck; Naquet, Philippe; Vouret-Craviari, Valérie; Mograbi, Baharia; Hofman, Paul M

    2009-06-01

    The acute phase of Crohn's disease (CD) is characterized by a large afflux of polymorphonuclear leukocytes (PMNL) into the mucosa and by the release of TNF-alpha. Conversion of inactive TNF-alpha into an active form requires the cleavage of a transmembrane TNF-alpha precursor by the TNF-alpha-converting enzyme (ADAM17), a protease mainly regulated by the tissue inhibitor of metalloproteinase 3 (TIMP3). The aim of the present study was to investigate in an in vitro model of PMNL transepithelial migration and in the intestinal mucosa of patients with CD the expression and regulation of ADAM17 and TIMP3 in intestinal epithelial cells (IEC). ADAM17 and TIMP3 expression was analyzed by Western blotting, RT-PCR, confocal microscopy, and immunohistochemistry by using the T84 model and digestive biopsies. ADAM17 expression in IEC was increased at a posttranscriptional level during the early phase (from 2 to 4 h) of PMNL transepithelial migration whereas TIMP3 was only increased 24 h later. TNF-alpha induced an early upregulation of ADAM17 in T84 cells, whereas PMNL adhesion, H(2)O(2), or epithelial tight junction opening alone did not affect the amount of ADAM17. Immunohistochemistry of intestinal biopsies revealed that strong expression of ADAM17 was associated with a high activity of CD. In contrast, TIMP3 was very poorly expressed in these biopsies. ADAM17 and TIMP3 profiling did not correlated with the NOD2/CARD15 status. The ADAM17 activity was higher both in the early phase of PMNL transepithelial migration and in active CD. These results showed early posttranscriptional upregulation of ADAM17 in IEC linked to PMNL transepithelial migration and a high activity of CD.

  16. A new species of Spiroberotha Adams 1989 (Neuroptera: Berothidae) and the first record of the genus in Brazil.

    PubMed

    Machado, Renato Jose Pires; Krolow, Tiago Kütter

    2016-03-20

    The genus Spiroberotha Adams, 1989 is classified in Berothidae (Neuroptera) with two described species: S. fernandezi Adams, 1989 from Venezuela and S. sanctarosae Adams, 1989 from Colombia, Costa Rica and Venezuela. Here we describe a new species, S. tocantinensis n. sp., from Palmas, Tocantins, Brazil. This is the first record of the genus in Brazil, extending its geographical distribution.

  17. 77 FR 5291 - The Designation of Monir Chouka, also Known as Mounir Chouka, Also Known as Abu Adam, Also Known...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE The Designation of Monir Chouka, also Known as Mounir Chouka, Also Known as Abu Adam, Also Known as Abu Adam From Germany, also Known as Abu Adam aus Deutschland, as a Specially Designated Global Terrorist Pursuant to Section 1(b) of Executive Order...

  18. The BH3 α-Helical Mimic BH3-M6 Disrupts Bcl-XL, Bcl-2, and MCL-1 Protein-Protein Interactions with Bax, Bak, Bad, or Bim and Induces Apoptosis in a Bax- and Bim-dependent Manner*

    PubMed Central

    Kazi, Aslamuzzaman; Sun, Jiazhi; Doi, Kenichiro; Sung, Shen-Shu; Takahashi, Yoshinori; Yin, Hang; Rodriguez, Johanna M.; Becerril, Jorge; Berndt, Norbert; Hamilton, Andrew D.; Wang, Hong-Gang; Sebti, Saïd M.

    2011-01-01

    A critical hallmark of cancer cell survival is evasion of apoptosis. This is commonly due to overexpression of anti-apoptotic proteins such as Bcl-2, Bcl-XL, and Mcl-1, which bind to the BH3 α-helical domain of pro-apoptotic proteins such as Bax, Bak, Bad, and Bim, and inhibit their function. We designed a BH3 α-helical mimetic BH3-M6 that binds to Bcl-XL and Mcl-1 and prevents their binding to fluorescently labeled Bak- or Bim-BH3 peptides in vitro. Using several approaches, we demonstrate that BH3-M6 is a pan-Bcl-2 antagonist that inhibits the binding of Bcl-XL, Bcl-2, and Mcl-1 to multi-domain Bax or Bak, or BH3-only Bim or Bad in cell-free systems and in intact human cancer cells, freeing up pro-apoptotic proteins to induce apoptosis. BH3-M6 disruption of these protein-protein interactions is associated with cytochrome c release from mitochondria, caspase-3 activation and PARP cleavage. Using caspase inhibitors and Bax and Bak siRNAs, we demonstrate that BH3-M6-induced apoptosis is caspase- and Bax-, but not Bak-dependent. Furthermore, BH3-M6 disrupts Bcl-XL/Bim, Bcl-2/Bim, and Mcl-1/Bim protein-protein interactions and frees up Bim to induce apoptosis in human cancer cells that depend for tumor survival on the neutralization of Bim with Bcl-XL, Bcl-2, or Mcl-1. Finally, BH3-M6 sensitizes cells to apoptosis induced by the proteasome inhibitor CEP-1612. PMID:21148306

  19. Novel Metal Ion Based Estrogen Mimics for Molecular Imaging

    SciTech Connect

    Rajagopalan, Raghavan

    2006-01-30

    The overall objective of the SBIR Phase I proposal is to prepare and evaluate a new class of {sup 99m}Tc or {sup 94m}Tc containing estrogen-like small molecules ('estrogen mimics') for SPECT or PET molecular imaging of estrogen receptor positive (ER+) tumors. In this approach, the metal ion is integrated into the estrone skeleton by isosteric substitution of a carbon atom in the steroidal structure to give new class of mimics that are topologically similar to the native estrogen (Fig. 1). Although both N{sub 2}S{sub 2} and N{sub 3}S mimics 1 and 2 were considered as target structures, molecular modeling study revealed that the presence of the acetyl group at position-15 in the N{sub 3}S mimic 2 causes steric hinderance toward binding of 2 to SHBG. Therefore, initial efforts were directed at the synthesis and evaluation of the N{sub 2}S{sub 2} mimic 1.

  20. Nuclear trafficking of the HIV-1 pre-integration complex depends on the ADAM10 intracellular domain

    SciTech Connect

    Endsley, Mark A.; Somasunderam, Anoma D.; Li, Guangyu; Oezguen, Numan; Thiviyanathan, Varatharasa; Murray, James L.; Rubin, Donald H.; Hodge, Thomas W.; and others

    2014-04-15

    Previously, we showed that ADAM10 is necessary for HIV-1 replication in primary human macrophages and immortalized cell lines. Silencing ADAM10 expression interrupted the HIV-1 life cycle prior to nuclear translocation of viral cDNA. Furthermore, our data indicated that HIV-1 replication depends on the expression of ADAM15 and γ-secretase, which proteolytically processes ADAM10. Silencing ADAM15 or γ-secretase expression inhibits HIV-1 replication between reverse transcription and nuclear entry. Here, we show that ADAM10 expression also supports replication in CD4{sup +} T lymphocytes. The intracellular domain (ICD) of ADAM10 associates with the HIV-1 pre-integration complex (PIC) in the cytoplasm and immunoprecipitates and co-localizes with HIV-1 integrase, a key component of PIC. Taken together, our data support a model whereby ADAM15/γ-secretase processing of ADAM10 releases the ICD, which then incorporates into HIV-1 PIC to facilitate nuclear trafficking. Thus, these studies suggest ADAM10 as a novel therapeutic target for inhibiting HIV-1 prior to nuclear entry. - Highlights: • Nuclear trafficking of the HIV-1 pre-integration complex depends on ADAM10. • ADAM10 associates with HIV-1 integrase in the pre-integration complex. • HIV-1 replication depends on the expression of ADAM15 and γ-secretase. • Silencing ADAM15 or γ-secretase expression inhibits nuclear import of viral cDNA. • ADAM10 is important for HIV-1 replication in human macrophages and CD4{sup +} T lymphocytes.

  1. Econophysical visualization of Adam Smith’s invisible hand

    NASA Astrophysics Data System (ADS)

    Cohen, Morrel H.; Eliazar, Iddo I.

    2013-02-01

    Consider a complex system whose macrostate is statistically observable, but yet whose operating mechanism is an unknown black-box. In this paper we address the problem of inferring, from the system’s macrostate statistics, the system’s intrinsic force yielding the observed statistics. The inference is established via two diametrically opposite approaches which result in the very same intrinsic force: a top-down approach based on the notion of entropy, and a bottom-up approach based on the notion of Langevin dynamics. The general results established are applied to the problem of visualizing the intrinsic socioeconomic force-Adam Smith’s invisible hand-shaping the distribution of wealth in human societies. Our analysis yields quantitative econophysical representations of figurative socioeconomic forces, quantitative definitions of “poor” and “rich”, and a quantitative characterization of the “poor-get-poorer” and the “rich-get-richer” phenomena.

  2. Defenses and morality: Adam Smith, Sigmund Freud, and contemporary psychoanalysis.

    PubMed

    Gabrinetti, Paul A; Özler, Sule

    2014-10-01

    In this paper we follow the development and transmission of moral learning from Adam Smith's impartial spectator to Sigmund Freud's superego and then to contemporary psychoanalysis. We argue that defenses are an integral component in the acquisition of any moral system. Elaborating on this argument, we assert that there is a progression from defensive systems that are "closed" to defensive systems that are "open," as defined in a recent work by Novick and Novick. The former system is "static, avoids reality, and is characterized by power dynamics, sadomasochism, and omnipotent defense." The latter, on the other hand, is a system that allows for "joy, creativity, spontaneity, love and it is attuned to reality." Furthermore, while Smith and Freud's systems are more one-person systems of defense, contemporary psychoanalysis has moved to more of a two-person system.

  3. Neptune's Discovery: Le Verrier, Adams, and the Assignment of Credit

    NASA Astrophysics Data System (ADS)

    Sheehan, William

    2011-01-01

    As one of the most significant achievements of 19th century astronomy, the discovery of Neptune has been the subject of a vast literature. A large part of this literature--beginning with the period immediately after the optical discovery in Berlin--has been the obsession with assigning credit to the two men who attempted to calculate the planet's position (and initially this played out against the international rivalry between France and England). Le Verrier and Adams occupied much different positions in the Scientific Establishments of their respective countries; had markedly different personalities; and approached the investigation using different methods. A psychiatrist and historian of astronomy tries to provide some new contexts to the familiar story of the discovery of Neptune, and argues that the personalities of these two men played crucial roles in their approaches to the problem they set themselves and the way others reacted to their stimuli. Adams had features of high-functioning autism, while Le Verrier's domineering, obsessive, orderly personality--though it allowed him to be immensely productive--eventually led to serious difficulties with his peers (and an outright revolt). Though it took extraordinary smarts to calculate the position of Neptune, the discovery required social skills that these men lacked--and thus the process to discovery was more bumbling and adventitious than it might have been. The discovery of Neptune occurred at a moment when astronomy was changing from that of heroic individuals to team collaborations involving multiple experts, and remains an object lesson in the sociological aspects of scientific endeavor.

  4. Soluble ADAM33 initiates airway remodeling to promote susceptibility for allergic asthma in early life

    PubMed Central

    Davies, Elizabeth R.; Kelly, Joanne F.C.; Howarth, Peter H.; Wilson, David I.; Holgate, Stephen T.; Davies, Donna E.; Whitsett, Jeffrey A.

    2016-01-01

    Asthma is a chronic inflammatory airways disease that usually begins in early life and involves gene-environment interactions. Although most asthma exhibits allergic inflammation, many allergic individuals do not have asthma. Here, we report how the asthma gene a disintegrin and metalloprotease 33 (ADAM33) acts as local tissue susceptibility gene that promotes allergic asthma. We show that enzymatically active soluble ADAM33 (sADAM33) is increased in asthmatic airways and plays a role in airway remodeling, independent of inflammation. Furthermore, remodeling and inflammation are both suppressed in Adam33-null mice after allergen challenge. When induced in utero or added ex vivo, sADAM33 causes structural remodeling of the airways, which enhances postnatal airway eosinophilia and bronchial hyperresponsiveness following subthreshold challenge with an aeroallergen. This substantial gene-environment interaction helps to explain the end-organ expression of allergic asthma in genetically susceptible individuals. Finally, we show that sADAM33-induced airway remodeling is reversible, highlighting the therapeutic potential of targeting ADAM33 in asthma. PMID:27489884

  5. EMMPRIN and ADAM12 in prostate cancer: preliminary results of a prospective study.

    PubMed

    Bilgin Doğru, Elif; Dizdar, Yavuz; Akşit, Ece; Ural, Feyyaz; Şanlı, Öner; Yasasever, Vildan

    2014-11-01

    Extracellular metalloproteinase inducer (EMMPRIN) and a disintegrin and metalloproteinase (ADAM12) play a major role in cancer invasion and metastasis owing to the fact that they are directly related to the cell microenvironment and extracellular matrix (ECM) degradation. The aim of this study was to search for an answer to the question "whether the determination of EMMPRIN and ADAM12 values especially in urine may be helpful for the early diagnosis of prostate cancer without employing invasive methods" and also to check whether they may be useful for the determination of the patients with high metastasis risk. Peripheral blood and urine from 66 prostate cancer patients (40 local, 20 locally advanced, 6 metastatic) and 14 healthy controls were evaluated by enzyme-linked immunosorbent assay (ELISA) method. Serum EMMPRIN and ADAM12 values of the patients were seen to be statistically higher than the serum EMMPRIN and ADAM12 values of the healthy controls (p=0.01 and p=0.001, respectively). The urine ADAM12 levels were significantly higher in patients (p=0.013). No significant relationships were found between urine EMMPRIN values of the patients and the healthy controls (p>0.05). Positive correlation between urine EMMPRIN-urine ADAM12 tests was found in total patients group (r=0.683, p=0.001). Our preliminary results revealed that serum EMMPRIN and ADAM12 values and urine ADAM12 values may be useful markers in prostate cancer therapy. Due to the high correlation between these two tests, we are of the opinion that the use of urine ADAM12 in clinic may be sufficient and favorable together with prostate-specific antigen (PSA) for treatment.

  6. Genomic organization and promoter analysis of the bovine ADAM12 gene.

    PubMed

    Taniguchi, Y; Doronbekov, K; Yamada, T; Sasaki, Y; Takano, A; Sugimoto, Y

    2008-01-01

    A disintegrin and metalloprotease (ADAM) 12 is a member of the ADAM family possessing a putative role in a variety of biological processes such as modulation of proteolytic processing, cell adhesion, cell fusion, and signaling. Recently, it has been suggested that ADAM12 is involved in regulation of adipogenesis as well as myogenesis. In this study, we have determined the genomic structure of 5'- and 3'-regions in the bovine ADAM12 gene. We could obtain characteristics of lower homology of its exon 2 with human counterpart. Human exon S19 encodes for the sequence specific to a shorter secreted form of ADAM12S. The bovine ADAM12 gene had no canonical 3'-splice acceptor site at 5'-side of the putative exon S19, suggesting that the cattle could not produce a ADAM12S counterpart. To identify the regulatory elements, a 12 kb 5'-flanking region of the gene was cloned and luciferase reporter assay was carried out. Reporter plasmids with different length of proximal promoter region indicated the similar patterns of promoter activities between 3T3-L1 preadipose and Cos-1 nonadipose cells. However, 2.0 and 0.2 kb fragments located at - 8 and - 4.5 kb upstream of the putative transcription start site, respectively, increased the ADAM12 promoter activity about 1.5- to 2-fold in 3T3-L1, but not in Cos-1. These results suggested that the two distal regions might contribute to the preadipocyte-specific expression of ADAM12 gene.

  7. Optimal Control In Predation Of Models And Mimics

    NASA Astrophysics Data System (ADS)

    Tsoularis, A.

    2007-09-01

    This paper examines optimal predation by a predator preying upon two types of prey, modes and mimics. Models are unpalatable prey and mimics are palatable prey resembling the models so as to derive some protection from predation. This biological phenomenon is known in Ecology as Batesian mimicry. An optimal control problem in continuous time is formulated with the sole objective to maximize the net energetic benefit to the predator from predation in the presence of evolving prey populations. The constrained optimal control is bang-bang with the scalar control taken as the probability of attacking prey. Conditions for the existence of singular controls are obtained.

  8. 5-HT4 Receptors Constitutively Promote the Non-Amyloidogenic Pathway of APP Cleavage and Interact with ADAM10

    PubMed Central

    2012-01-01

    In addition to the amyloidogenic pathway, amyloid precursor protein (APP) can be cleaved by α-secretases, producing soluble and neuroprotective APP alpha (sAPPα) (nonamyloidogenic pathway) and thus preventing the generation of pathogenic amyloid-β. However, the mechanisms regulating APP cleavage by α-secretases remain poorly understood. Here, we showed that expression of serotonin type 4 receptors (5-HT4Rs) constitutively (without agonist stimulation) induced APP cleavage by the α-secretase ADAM10 and the release of neuroprotective sAPPα in HEK-293 cells and cortical neurons. This effect was independent of cAMP production. Interestingly, we demonstrated that 5-HT4 receptors physically interacted with the mature form of ADAM10. Stimulation of 5-HT4 receptors by an agonist further increased sAPPα secretion, and this effect was mediated by cAMP/Epac signaling. These findings describe a new mechanism whereby a GPCR constitutively stimulates the cleavage of APP by α-secretase and promotes the nonamyloidogenic pathway of APP processing. PMID:23336052

  9. HIV-Nef and ADAM17-Containing Plasma Extracellular Vesicles Induce and Correlate with Immune Pathogenesis in Chronic HIV Infection

    PubMed Central

    Lee, Jung-Hyun; Schierer, Stephan; Blume, Katja; Dindorf, Jochen; Wittki, Sebastian; Xiang, Wei; Ostalecki, Christian; Koliha, Nina; Wild, Stefan; Schuler, Gerold; Fackler, Oliver T.; Saksela, Kalle; Harrer, Thomas; Baur, Andreas S.

    2016-01-01

    Antiretroviral therapy (ART) efficiently suppresses HIV replication but immune activation and low CD4 T cell counts often persist. The underlying mechanism of this ART-resistant pathogenesis is not clear. We observed that levels of plasma extracellular vesicles (pEV) are strongly elevated in HIV infection and do not decline during ART. Surprisingly, these vesicles contained the viral accessory proteins Nef and Vpu, which are assumed to be not expressed under efficient ART, as well as pro-inflammatory effectors, including activated ADAM17. HIV pEV were characterized by the presence of activated αvβ3 and absence of CD81 and Tsg101. Correlating with immune activation, peripheral monocytes ingested large amounts of pEV, giving rise to an increased population of CD1c+ CD14+ cells that secreted inflammatory cytokines. Importantly, the pro-inflammatory content, particularly ADAM17 activity, correlated with low T cell counts. Preliminary evidence suggested that HIV pEV derived from peripheral mononuclear cells and from an unknown myeloid cell population. In summary we propose an important role of pro-inflammatory pEV in chronic HIV infection due to ongoing viral Nef activity. PMID:27211553

  10. HIV-Nef and ADAM17-Containing Plasma Extracellular Vesicles Induce and Correlate with Immune Pathogenesis in Chronic HIV Infection.

    PubMed

    Lee, Jung-Hyun; Schierer, Stephan; Blume, Katja; Dindorf, Jochen; Wittki, Sebastian; Xiang, Wei; Ostalecki, Christian; Koliha, Nina; Wild, Stefan; Schuler, Gerold; Fackler, Oliver T; Saksela, Kalle; Harrer, Thomas; Baur, Andreas S

    2016-04-01

    Antiretroviral therapy (ART) efficiently suppresses HIV replication but immune activation and low CD4 T cell counts often persist. The underlying mechanism of this ART-resistant pathogenesis is not clear. We observed that levels of plasma extracellular vesicles (pEV) are strongly elevated in HIV infection and do not decline during ART. Surprisingly, these vesicles contained the viral accessory proteins Nef and Vpu, which are assumed to be not expressed under efficient ART, as well as pro-inflammatory effectors, including activated ADAM17. HIV pEV were characterized by the presence of activated αvβ3 and absence of CD81 and Tsg101. Correlating with immune activation, peripheral monocytes ingested large amounts of pEV, giving rise to an increased population of CD1c(+) CD14(+) cells that secreted inflammatory cytokines. Importantly, the pro-inflammatory content, particularly ADAM17 activity, correlated with low T cell counts. Preliminary evidence suggested that HIV pEV derived from peripheral mononuclear cells and from an unknown myeloid cell population. In summary we propose an important role of pro-inflammatory pEV in chronic HIV infection due to ongoing viral Nef activity.

  11. The immunoregulator soluble TACI is released by ADAM10 and reflects B-cell activation in autoimmunity

    PubMed Central

    Hoffmann, Franziska S.; Kuhn, Peer-Hendrik; Laurent, Sarah A.; Hauck, Stefanie M.; Berer, Kerstin; Wendlinger, Simone A.; Krumbholz, Markus; Khademi, Mohsen; Olsson, Tomas; Dreyling, Martin; Pfister, Hans-Walter; Alexander, Tobias; Hiepe, Falk; Kümpfel, Tania; Crawford, Howard C.; Wekerle, Hartmut; Hohlfeld, Reinhard; Lichtenthaler, Stefan F.; Meinl, Edgar

    2014-01-01

    BAFF and APRIL, which control B-cell homeostasis, are therapeutic targets in autoimmune diseases. TACI-Fc (atacicept), a soluble fusion protein containing the extracellular domain of the BAFF-APRIL-receptor TACI, was applied in clinical trials. However disease activity in multiple sclerosis (MS) unexpectedly increased, whereas in systemic lupus erythematosus (SLE) atacicept was beneficial. Here, we show that an endogenous soluble form of TACI exists in vivo. TACI proteolysis involved shedding by ADAM10 releasing sTACI from activated B cells. The membrane-bound stub was subsequently cleaved by γ-secretase reducing ligand-independent signaling of the remaining C-terminal fragment. The shed ectodomain assembled ligand-independently in a homotypic way. It functioned as a decoy receptor inhibiting BAFF- and APRIL-mediated B-cell survival and NFκB-activation. We determined sTACI levels in autoimmune diseases with established hyper-activation of the BAFF-APRIL system. sTACI levels were elevated both in the cerebrospinal fluid (CSF) of the brain-restricted autoimmune disease MS correlating with intrathecal IgG production, as well as in the serum of the systemic autoimmune disease SLE correlating with disease activity. Together, we show that TACI is sequentially processed by ADAM10 and γ-secretase. The released sTACI is an immunoregulator that shares decoy functions with atacicept. Itreflectssystemic and compartmentalized B-cell accumulation and activation. PMID:25505277

  12. Selective inhibition of ADAM12 catalytic activity through engineering of tissue inhibitor of metalloproteinase 2 (TIMP-2).

    PubMed

    Kveiborg, Marie; Jacobsen, Jonas; Lee, Meng-Huee; Nagase, Hideaki; Wewer, Ulla M; Murphy, Gillian

    2010-08-15

    The disintegrin and metalloprotease ADAM12 has important functions in normal physiology as well as in diseases, such as cancer. Little is known about how ADAM12 confers its pro-tumorigenic effect; however, its proteolytic capacity is probably a key component. Thus selective inhibition of ADAM12 activity may be of great value therapeutically and as an investigative tool to elucidate its mechanisms of action. We have previously reported the inhibitory profile of TIMPs (tissue inhibitor of metalloproteinases) against ADAM12, demonstrating in addition to TIMP-3, a unique ADAM-inhibitory activity of TIMP-2. These findings strongly suggest that it is feasible to design a TIMP mutant selectively inhibiting ADAM12. With this purpose, we characterized the molecular determinants of the ADAM12-TIMP complex formation as compared with known molecular requirements for TIMP-mediated inhibition of ADAM17/TACE (tumour necrosis factor alpha-converting enzyme). Kinetic analysis using a fluorescent peptide substrate demonstrated that the molecular interactions of N-TIMPs (N-terminal domains of TIMPs) with ADAM12 and TACE are for the most part comparable, yet revealed strikingly unique features of TIMP-mediated ADAM12 inhibition. Intriguingly, we found that removal of the AB-loop in N-TIMP-2, which is known to impair its interaction with TACE, resulted in increased affinity to ADAM12. Importantly, using a cell-based epidermal growth factor-shedding assay, we demonstrated for the first time an inhibitory activity of TIMPs against the transmembrane ADAM12-L (full-length ADAM12), verifying the distinctive inhibitory abilities of N-TIMP-2 and engineered N-TIMP-2 mutants in a cellular environment. Taken together, our findings support the idea that a distinctive ADAM12 inhibitor with future therapeutic potential can be designed.

  13. Spontaneous activation of [FeFe]-hydrogenases by an inorganic [2Fe] active site mimic

    PubMed Central

    Esselborn, Julian; Berggren, Gustav; Noth, Jens; Siebel, Judith; Hemschemeier, Anja; Artero, Vincent; Reijerse, Edward; Fontecave, Marc; Lubitz, Wolfgang; Happe, Thomas

    2013-01-01

    Hydrogenases catalyze the formation of hydrogen. The cofactor (H-cluster) of [FeFe]-hydrogenases consists of a [4Fe-4S]-cluster bridged to a unique [2Fe]-subcluster whose biosynthesis in vivo requires hydrogenase-specific maturases. Here we show that a chemical mimic of the [2Fe]-subcluster can reconstitute apo-hydrogenase to full activity, independent of helper proteins. The assembled H-cluster is virtually indistinguishable from the native cofactor. This procedure will be a powerful tool for developing novel artificial H2-producing catalysts. PMID:23934246

  14. Solid-phase-supported synthesis of morpholinoglycine oligonucleotide mimics

    PubMed Central

    Belov, Sergey S; Tarasenko, Yulia V; Silnikov, Vladimir N

    2014-01-01

    Summary An efficient solid-phase-supported peptide synthesis (SPPS) of morpholinoglycine oligonucleotide (MorGly) mimics has been developed. The proposed strategy includes a novel specially designed labile linker group containing the oxalyl residue and the 2-aminomethylmorpholino nucleoside analogues as first subunits. PMID:24991266

  15. Estimation of MIMIC Model Parameters with Multilevel Data

    ERIC Educational Resources Information Center

    Finch, W. Holmes; French, Brian F.

    2011-01-01

    The purpose of this simulation study was to assess the performance of latent variable models that take into account the complex sampling mechanism that often underlies data used in educational, psychological, and other social science research. Analyses were conducted using the multiple indicator multiple cause (MIMIC) model, which is a flexible…

  16. Design of the MIMIC Network for Preparing Tomorrow's Teachers.

    ERIC Educational Resources Information Center

    Abate, Ronald J.; Jin, Seung

    This paper provides an overview of the variables critical to the success of an Internet site design. The site under development represents one aspect of dissemination for the Modeling Instruction with Modern Information and Communications Technologies: the MIMIC Project, a U.S. Department of Education Capacity Building Grant. The site focuses on…

  17. Expression of FAP, ADAM12, WISP1, and SOX11 is heterogeneous in aggressive fibromatosis and spatially relates to the histologic features of tumor activity.

    PubMed

    Misemer, Benjamin S; Skubitz, Amy P N; Carlos Manivel, J; Schmechel, Stephen C; Cheng, Edward Y; Henriksen, Jonathan C; Koopmeiners, Joseph S; Corless, Christopher L; Skubitz, Keith M

    2014-02-01

    Aggressive fibromatosis (AF) represents a group of tumors with a variable and unpredictable clinical course, characterized by a monoclonal proliferation of myofibroblastic cells. The optimal treatment for AF remains unclear. Identification and validation of genes whose expression patterns are associated with AF may elucidate biological mechanisms in AF, and aid treatment selection. This study was designed to examine the protein expression by immunohistochemistry (IHC) of four genes, ADAM12, FAP, SOX11, and WISP1, that were found in an earlier study to be uniquely overexpressed in AF compared with normal tissues. Digital image analysis was performed to evaluate inter- and intratumor heterogeneity, and correlate protein expression with histologic features, including a histopathologic assessment of tumor activity, defined by nuclear chromatin density ratio (CDR). AF tumors exhibited marked inter- and intratumor histologic heterogeneity. Pathologic assessment of tumor activity and digital assessment of average nuclear size and CDR were all significantly correlated. IHC revealed protein expression of all four genes. IHC staining for ADAM12, FAP, and WISP1 correlated with CDR and was higher, whereas SOX11 staining was lower in tumors with earlier recurrence following excision. All four proteins were expressed, and the regional variation in tumor activity within and among AF cases was demonstrated. A spatial correlation between protein expression and nuclear morphology was observed. IHC also correlated with the probability of recurrence following excision. These proteins may be involved in AF pathogenesis and the corresponding pathways could serve as potential targets of therapy.

  18. The Fall of Adam Osborne: Why His Company Failed and What It Means for Personal Computing.

    ERIC Educational Resources Information Center

    Immel, A. Richard

    1984-01-01

    Discusses some of the reasons for the failure of the Osborne Computer Corporation, including Adam Osborne's personality and background, the people he selected to run the company, and lack of financial controls. (MBR)

  19. ADAM 10 expression in primary uveal melanoma as prognostic factor for risk of metastasis.

    PubMed

    Caltabiano, Rosario; Puzzo, Lidia; Barresi, Valeria; Ieni, Antonio; Loreto, Carla; Musumeci, Giuseppe; Castrogiovanni, Paola; Ragusa, Marco; Foti, Pietro; Russo, Andrea; Longo, Antonio; Reibaldi, Michele

    2016-11-01

    Uveal melanoma is the most frequent primary intraocular neoplasm in adults. Although malignant melanoma may be located at any point in the uveal tract, the choroid and ciliary body are more frequent locations than the iris. In the present study, we examined ADAM10 expression levels in primary uveal melanoma both with and without metastasis, and we evaluated their association with other high risk characteristics for metastasis in order to assess if ADAM10 can be used to predict metastasis. This study included a total of 52 patients, 23 men and 29 women, with uveal melanoma. A significantly high expression of ADAM-10 was seen in patients with metastasis (11/13, 84.6%), but not in patients without metastasis (15/39, 38.5%). In conclusion we found that ADAM10 expression was associated with a more rapid metastatic progression confirming its role in uveal melanoma metastasis.

  20. ISS Update: Adam Naids on Creating "€œNASA Johnson Style"

    NASA Video Gallery

    Public Affairs Officer Dan Huot talks to Adam Naids, Hardware Development Engineer, one of the creators of the successful "€œGangnam Style" parody video "€œNASA Johnson Style."€ Featured on NASAâ€...

  1. Highlighting High Performance: Adam Joseph Lewis Center for Environmental Studies, Oberlin College, Oberlin, Ohio

    SciTech Connect

    2002-11-01

    Oberlin College’s Adam Joseph Lewis Center for Environmental Studies is a high-performance building featuring an expansive photovoltaic system and a closed-loop groundwater heat pump system. Designers incorporated energy-efficient components and materials

  2. Two Paralogous Tetraspanins TSP-12 and TSP-14 Function with the ADAM10 Metalloprotease SUP-17 to Promote BMP Signaling in Caenorhabditis elegans

    PubMed Central

    Shi, Herong

    2017-01-01

    The highly conserved bone morphogenetic protein (BMP) signaling pathway regulates many developmental and homeostatic processes. While the core components of the BMP pathway have been well studied, much research is needed for understanding the mechanisms involved in the precise spatiotemporal control of BMP signaling in vivo. Here, we provide evidence that two paralogous and evolutionarily conserved tetraspanins, TSP-12 and TSP-14, function redundantly to promote BMP signaling in C. elegans. We further show that the ADAM10 (a disintegrin and metalloprotease 10) ortholog SUP-17 also functions to promote BMP signaling, and that TSP-12 can bind to and promote the cell surface localization of SUP-17. SUP-17/ADAM10 is known to be involved in the ligand-induced proteolytic processing of the Notch receptor. We have evidence that the function of SUP-17, and of TSP-12/TSP-14 in BMP signaling is independent of their roles in Notch signaling. Furthermore, presenilins, core components of the γ-secretase complex involved in processing Notch, do not appear to play a role in BMP signaling. These studies established a new role of the TSP-12/TSP-14/SUP-17 axis in regulating BMP signaling, in addition to their known function in the Notch signaling pathway. We also provide genetic evidence showing that a known BMP signaling modulator, UNC-40/neogenin/DCC, is one of the substrates of SUP-17/ADAM10 in the BMP signaling pathway. PMID:28068334

  3. Expression of ADAM12 is regulated by E2F1 in small cell lung cancer.

    PubMed

    Li, Zunling; Wang, Yaopeng; Kong, Lijun; Yue, Zhen; Ma, Ying; Chen, Xufang

    2015-12-01

    Our previous study reported that ADAM12 was highly expressed in small cell lung cancer (SCLC) and could be an effective marker for diagnosis and prognosis. Yet, the reason for the high expression of ADAM12 in SCLC requires further elucidation. Transcription factor E2F1 has been receiving increasing attention due to the complexity and diversity of its function in cancer. In the present study, the expression of ADAM12 was significantly decreased following silencing of E2F1 expression by siRNA, thus indicating that E2F1 may regulate the expression of ADAM12 at the level of transcription. Chromatin immunoprecipitation-to-sequence analysis identified three binding sites for E2F1 in the locus for ADAM12. They were Chr10: 128010444-128011026, located in the intron of ADAM12, named seq0; Chr10: 128076927‑128078127, located in the promoter of ADAM12, named seq1; and Chr10: 128086195‑128086876, located in the upstream 20 kb from the transcription start site of ADAM12, named: seq2. Dual‑luciferase reporter experiments revealed that seq1 not seq0 and seq2 was able to promote the expression of luciferase. Notably, co-transfection of E2F1 significantly increased the activity of seq1 not seq0 and seq2, but quantitative polymerase chain reaction results showed that seq0, seq1 and seq2 could recruit E2F1, indicating that the influence of E2F1 in regulating the expression of ADAM12 was complex. Sequence analysis clarified that seq1 was a part of the ADAM12 promoter, yet the functions of seq0 and seq2 were unknown. Fusion fragments containing seq0-seq1 or seq2-seq1 were analyzed in luciferase constructs. Compared with seq1 alone, the activities of these fusion fragments were non-significantly reduced. The activities of fusion fragments were significantly decreased following co-transfection with E2F1. Thus, the present findings support the conclusion that the E2F1 transcription factor regulates the expression of ADAM12 by binding differential cis-acting elements.

  4. ADAM17 Inhibitors Attenuate Corneal Epithelial Detachment Induced by Mustard Exposure

    PubMed Central

    DeSantis-Rodrigues, Andrea; Chang, Yoke-Chen; A. Hahn, Rita; P. Po, Iris; Zhou, Peihong; Lacey, C. Jeffrey; Pillai, Abhilash; C. Young, Sherri; A. Flowers II, Robert; A. Gallo, Michael; D. Laskin, Jeffrey; R. Gerecke, Donald; K. H. Svoboda, Kathy; D. Heindel, Ned; Gordon, Marion K.

    2016-01-01

    Purpose Sulfur mustard, nitrogen mustard (NM), and 2-chloroethyl ethyl sulfide all cause corneal injury with epithelial–stromal separation, differing only by degree. Injury can resolve in a few weeks or develop into chronic corneal problems. These vesicants induce microbullae at the epithelial–stromal junction, which is partially caused by cleavage of transmembranous hemidesmosomal collagen XVII, a component anchoring the epithelium to the stroma. ADAM17 is an enzyme involved in wound healing and is able to cleave collagen XVII. The activity of ADAM17 was inhibited in vesicant-exposed corneas by four different hydroxamates, to evaluate their therapeutic potential when applied 2 hours after exposure, thereby allowing ADAM17 to perform its early steps in wound healing. Methods Rabbit corneal organ cultures exposed to NM for 2 hours were washed, then incubated at 37°C for 22 hours, with or without one of the four hydroxamates (dose range, 0.3–100 nmol in 20 μL, applied four times). Corneas were analyzed by light and immunofluorescence microscopy, and ADAM17 activity assays. Results Nitrogen mustard–induced corneal injury showed significant activation of ADAM17 levels accompanying epithelial–stromal detachment. Corneas treated with hydroxamates starting 2 hours post exposure showed a dose-dependent ADAM17 activity inhibition up to concentrations of 3 nmol. Of the four hydroxamates, NDH4417 (N-octyl-N-hydroxy-2-[4-hydroxy-3-methoxyphenyl] acetamide) was most effective for inhibiting ADAM17 and retaining epithelial–stromal attachment. Conclusions Mustard exposure leads to corneal epithelial sloughing caused, in part, by the activation of ADAM17 at the epithelial–stromal junction. Select hydroxamate compounds applied 2 hours after NM exposure mitigated epithelial–stromal separation. PMID:27058125

  5. Engineering of Specific Tissue Inhibitors to Block ADAM Type Metalloprotease-Mediated Mammary Neoplasia

    DTIC Science & Technology

    2001-07-01

    ADAM9 cleaves the HB- EGF when PKCd is activated, but neither the wildtype, nor the dominant-negative ADAM9, affects the EGFR transactivation (Izumi et...S. V. Subramanian, M. L. Fitzgerald, M. Bernfield, J. Bi- that accounts for these observations re- not other TIMPs, induce apoptosis (19). e!. Chem...12. D. Pan and G. M. Rubin, Cell90, 271 (1997). fy the cytoplasmic domains of the pro- and induces apoptosis by binding to the Fas 13. C. Cho et a

  6. Natural soluble interleukin-15Ralpha is generated by cleavage that involves the tumor necrosis factor-alpha-converting enzyme (TACE/ADAM17).

    PubMed

    Budagian, Vadim; Bulanova, Elena; Orinska, Zane; Ludwig, Andreas; Rose-John, Stefan; Saftig, Paul; Borden, Ernest C; Bulfone-Paus, Silvia

    2004-09-24

    This study shows that the high affinity alpha-chain of the interleukin (IL)-15 receptor exists not only in membrane-anchored but also in soluble form. Soluble IL-15Ralpha (sIL-15Ralpha) can be detected in mouse sera and cell-conditioned media by enzyme-linked immunosorbent assay and by immunoprecipitation and Western blotting. This protein has a molecular mass of about 30 kDa because of the presence of a single N-glycosylation site, which is reduced to 26 kDa after N-glycosidase treatment. Transmembrane IL-15Ralpha is constitutively converted into its soluble form by proteolytic cleavage that involves tumor necrosis factor-alpha-converting enzyme (TACE), and this process is further enhanced by phorbol 12-myristate 13-acetate (PMA) stimulation. The hydroxamate GW280264X, which is capable of blocking TACE and the closely related disintegrin-like metalloproteinase 10 (ADAM10), effectively inhibited both spontaneous and PMA-inducible cleavage of IL-15Ralpha, whereas GI254023X, which preferentially blocks ADAM10, was ineffective. Overexpression of TACE but not ADAM10 in COS-7 cells enhanced the constitutive and PMA-inducible cleavage of IL-15Ralpha. Moreover, murine fibroblasts deficient in TACE but not ADAM10 expression exhibited a significant reduction in the spontaneous and inducible IL-15Ralpha shedding, whereas a reconstitution of TACE in these cells restored the release of sIL-15Ralpha, thereby suggesting that TACE-mediated proteolysis may represent a major mechanism for sIL-15Ralpha generation in mice. The existence of natural sIL-15Ralpha offers novel insights into the complex biology of IL-15 and envisages a new level for therapeutic intervention.

  7. Geologic map and geothermal assessment of the Mount Adams volcanic field, Cascade Range of southern Washington

    USGS Publications Warehouse

    Hildreth, Wes; Fierstein, Judy

    1990-01-01

    More than 60 Quaternary vents make up the basalt-to-rhyodacite Mount Adams volcanic field and have erupted scoriae and lavas with a total volume of >370 km3. The Mount Adams andesite-dacite stratocone itself is a compound edifice that includes the high cone above 2300 m (20-10 ka), remnants of at least two earlier andesite-dacite cones as old as 0.5 Ma, and 7 Holocene flank vents. Four other Holocene vents and tens of vents contemporaneous with Mount Adams are peripheral to the stratocone. All of these vents, including Mount Adams, lie within a N-S eruptive zone 55 km long and 5 km wide. The age of all known Mount Adams silicic products (>100 ka) and the heterogeneous mafic compositions of the summit cone and Holocene lavas make it unlikely that the stratocone is underlain by an upper-crustal reservoir. Rather, the stratocone at the focus is built up of fractionated hybrid magmas that rise from MASH zones (melting-assimilation-storage-homogenization). The pyroclastic core of breccia and scoria at Mount Adams has undergone acid-sulfate leaching and deposition of alunite, kaolinite, silica, gypsum, sulfur, and Fe-oxides and has been a constant source of avalanches and debris flows. Most heat supplied from depth to the fumarolically altered core is dispersed by the high precipitation rate and high permeability of the rubbly lava flows so that a hydrothermal convection pattern is not maintained. Summit-restricted fumaroles are weak and diffuse.

  8. ADAMS/WT advanced development - version 1.4 and beyond

    SciTech Connect

    Elliott, A.S.; Depauw, T.R.

    1996-12-31

    ADAMS/WT is an wind-turbine-specific shell for the general-purpose mechanical system simulation package ADAMS5. It was developed under the guidance of the National Renewable Energy Laboratory to give engineers and analysts in the wind turbine community access to the analytical power of ADAMS, without having to become expert in its particular technology. The 1.4 version of ADAMS/WT is the most recent upgrade to the package, incorporating the most up-to-date version of the AeroDyn aerodynamic forcing subroutines from the University of Utah. It is also the first version to be made available on the Windows/NT platform. In version 1.4, ADAMS/WT has been significantly improved throughout and runs much faster. Automatic generation of standardized output has been added. The documentation has been extensively augmented with more detailed descriptions, more figures and more examples. ADAMS/WT remains the most powerful analytical tool available for horizontal-axis wind turbine development. 10 figs.

  9. Dual functions of cell-autonomous and non-cell-autonomous ADAM10 activity in granulopoiesis.

    PubMed

    Yoda, Masaki; Kimura, Tokuhiro; Tohmonda, Takahide; Uchikawa, Shinichi; Koba, Takeshi; Takito, Jiro; Morioka, Hideo; Matsumoto, Morio; Link, Daniel C; Chiba, Kazuhiro; Okada, Yasunori; Toyama, Yoshiaki; Horiuchi, Keisuke

    2011-12-22

    Previous studies have revealed various extrinsic stimuli and factors involved in the regulation of hematopoiesis. Among these, Notch-mediated signaling has been suggested to be critically involved in this process. Herein, we show that conditional inactivation of ADAM10, a membrane-bound protease with a crucial role in Notch signaling (S2 cleavage), results in myeloproliferative disorder (MPD) highlighted by severe splenomegaly and increased populations of myeloid cells and hematopoietic stem cells. Reciprocal transfer of bone marrow cells between wild-type and ADAM10 mutant mice revealed that ADAM10 activity in both hematopoietic and nonhematopoietic cells is involved in the development of MPD. Notably, we found that MPD caused by lack of ADAM10 in nonhematopoietic cells was mediated by G-CSF, whereas MPD caused by ADAM10-deficient hematopoietic cells was not. Taken together, the present findings reveal previously undescribed nonredundant roles of cell-autonomous and non-cell-autonomous ADAM10 activity in the maintenance of hematopoiesis.

  10. Increased abundance of ADAM9 transcripts in the blood is associated with tissue damage

    PubMed Central

    Rinchai, Darawan; Kewcharoenwong, Chidchamai; Kessler, Bianca; Lertmemongkolchai, Ganjana; Chaussabel, Damien

    2016-01-01

    Background: Members of the ADAM (a disintegrin and metalloprotease domain) family have emerged as critical regulators of cell-cell signaling during development and homeostasis. ADAM9 is consistently overexpressed in various human cancers, and has been shown to play an important role in tumorigenesis. However, little is known about the involvement of ADAM9 during immune-mediated processes. Results: Mining of an extensive compendium of transcriptomic datasets identified important gaps in knowledge regarding the possible role of ADAM9 in immunological homeostasis and inflammation: 1) The abundance of ADAM9 transcripts in the blood was increased in patients with acute infection but, 2) changed very little after in vitro exposure to a wide range of pathogen-associated molecular patterns (PAMPs). 3) Furthermore it was found to increase significantly in subjects as a result of tissue injury or tissue remodeling, in absence of infectious processes. Conclusions: Our findings indicate that ADAM9 may constitute a valuable biomarker for the assessment of tissue damage, especially in clinical situations where other inflammatory markers are confounded by infectious processes. PMID:27990250

  11. Lack of ADAM10 in endothelial cells affects osteoclasts at the chondro-osseus junction.

    PubMed

    Zhao, Ren; Wang, Aimin; Hall, Katherine C; Otero, Miguel; Weskamp, Gisela; Zhao, Baohong; Hill, Daniel; Goldring, Mary B; Glomski, Krzysztof; Blobel, Carl P

    2014-02-01

    Mice lacking ADAM10 in endothelial cells (Adam10ΔEC mice) have shorter femurs, tibiae, and humeri than controls, raising questions about how endothelial cells could control long bone growth. We performed a histopathological evaluation of the femur and tibia growth plates at different postnatal stages, and assessed the distribution of TRAP-positive osteoclasts and endothelial cells at the growth plate. The growth plates in Adam10ΔEC mice appeared normal at P7 and P14, but a thickened zone of hypertrophic chondrocytes and increased trabecular bone density were apparent by P21 and later. The number of TRAP+ cells at the COJ was normal at P7 and P14, but was strongly reduced at P21 and later. Moreover, the density of endomucin-stained endothelial cells at the COJ was increased starting at P7. The defects in long bone growth in Adam10ΔEC mice could be caused by a lack of osteoclastogenesis at the COJ. Moreover, ADAM10 appears to regulate endothelial cell organization in the developing bone vasculature, perhaps in a similar manner as in the developing retinal vascular tree, where ADAM10 is thought to control Notch-dependent endothelial cell fate decisions. This study provides evidence for the regulation of osteoclast function by endothelial cells in vivo.

  12. The metalloprotease ADAM12 regulates the effector function of human Th17 cells.

    PubMed

    Zhou, Angela X; El Hed, Aimee; Mercer, Frances; Kozhaya, Lina; Unutmaz, Derya

    2013-01-01

    A key modulator of immune homeostasis, TGFβ has an important role in the differentiation of regulatory T cells (Tregs) and IL-17-secreting T cells (Th17). How TGFβ regulates these functionally opposing T cell subsets is not well understood. We determined that an ADAM family metalloprotease called ADAM12 is specifically and highly expressed in both Tregs and CCR6+ Th17 cells. ADAM12 is induced in vitro upon differentiation of naïve T cells to Th17 cells or IL-17-secreting Tregs. Remarkably, silencing ADAM12 expression in CCR6+ memory T cells enhances the production of Th17 cytokines, similar to suppressing TGFβ signaling. Further, ADAM12 knockdown in naïve human T cells polarized towards Th17/Treg cells, or ectopically expressing RORC, greatly enhances IL-17-secreting cell differentiation, more potently then inhibiting TGFβ signals. Together, our findings reveal a novel regulatory role for ADAM12 in Th17 cell differentiation or function and may have implications in regulating their aberrant responses during immune pathologies.

  13. Extracellular engagement of ADAM12 induces clusters of invadopodia with localized ectodomain shedding activity.

    PubMed

    Albrechtsen, Reidar; Stautz, Dorte; Sanjay, Archana; Kveiborg, Marie; Wewer, Ulla M

    2011-01-15

    Invadopodia are dynamic actin structures at the cell surface that degrade extracellular matrix and act as sites of signal transduction. The biogenesis of invadopodia, including the mechanisms regulating their formation, composition, and turnover is not entirely understood. Here, we demonstrate that antibody ligation of ADAM12, a transmembrane disintegrin and metalloprotease, resulted in the rapid accumulation of invadopodia with extracellular matrix-degrading capacity in epithelial cells expressing the αvβ3 integrin and active c-Src kinase. The induction of invadopodia clusters required an intact c-Src interaction site in the ADAM12 cytoplasmic domain, but was independent of the catalytic activity of ADAM12. Caveolin-1 and transmembrane protease MMP14/MT1-MMP were both present in the ADAM12-induced clusters of invadopodia, and cholesterol depletion prevented their formation, suggesting that lipid-raft microdomains are involved in the process. Importantly, our data demonstrate that ADAM12-mediated ectodomain shedding of epidermal growth factor receptor ligands can occur within these invadopodia. Such localized growth factor signalling offers an interesting novel biological concept highly relevant to the properties of carcinoma cells, which often show upregulated ADAM12 and β3 integrin expression, together with high levels of c-Src kinase activity.

  14. The disintegrin-like metalloproteinase ADAM10 is involved in constitutive cleavage of CX3CL1 (fractalkine) and regulates CX3CL1-mediated cell-cell adhesion.

    PubMed

    Hundhausen, Christian; Misztela, Dominika; Berkhout, Theo A; Broadway, Neil; Saftig, Paul; Reiss, Karina; Hartmann, Dieter; Fahrenholz, Falk; Postina, Rolf; Matthews, Vance; Kallen, Karl-Josef; Rose-John, Stefan; Ludwig, Andreas

    2003-08-15

    The CX3C chemokine fractalkine (CX3CL1) exists as a membrane-expressed protein promoting cell-cell adhesion and as a soluble molecule inducing chemotaxis. Transmembrane CX3CL1 is converted into its soluble form by defined proteolytic cleavage (shedding), which can be enhanced by stimulation with phorbol-12-myristate-13-acetate (PMA). PMA-induced CX3CL1 shedding has been shown to involve the tumor necrosis factor-alpha-converting enzyme (TACE), whereas the constitutive cleavage in unstimulated cells remains elusive. Here we demonstrate a role of the closely related disintegrin-like metalloproteinase 10 (ADAM10) in the constitutive CX3CL1 cleavage. The hydroxamate GW280264X, capable of blocking TACE as well as ADAM10, proved to be an effective inhibitor of the constitutive and the PMA-inducible CX3CL1 cleavage in CX3CL1-expressing ECV-304 cells (CX3CL1-ECV-304), whereas GI254023X, preferentially blocking ADAM10 but not TACE, reduced the constitutive cleavage only. Overexpression of ADAM10 in COS-7 cells enhanced constitutive cleavage of CX3CL1 and, more importantly, in murine fibroblasts deficient of ADAM10 constitutive CX3CL1 cleavage was markedly reduced. Thus, ADAM10 contributes to the constitutive shedding of CX3CL1 in unstimulated cells. Addressing the functional role of CX3CL1 shedding for the adhesion of monocytic cells via membrane-expressed CX3CL1, we found that THP-1 cells adhere to CX3CL1-ECV-304 cells but detach in the course of vigorous washing. Inhibition of ADAM10-mediated CX3CL1 shedding not only increased adhesive properties of CX3CL1-ECV-304 cells but also prevented de-adhesion of bound THP-1 cells. Our data demonstrate that ADAM10 is involved in the constitutive cleavage of CX3CL1 and thereby may regulate the recruitment of monocytic cells to CX3CL1-expressing cell layers.

  15. Dynamics of ADAM17-Mediated Shedding of ACE2 Applied to Pancreatic Islets of Male db/db Mice

    PubMed Central

    Pedersen, Kim Brint; Chodavarapu, Harshita; Porretta, Constance; Robinson, Leonie K.

    2015-01-01

    Angiotensin-converting enzyme 2 (ACE2) gene therapy aimed at counteracting pancreatic ACE2 depletion improves glucose regulation in two diabetic mouse models: db/db mice and angiotensin II-infused mice. A disintegrin and metalloproteinase 17 (ADAM17) can cause shedding of ACE2 from the cell membrane. The aim of our studies was to determine whether ADAM17 depletes ACE2 levels in pancreatic islets and β-cells. Dynamics of ADAM17-mediated ACE2 shedding were investigated in 832/13 insulinoma cells. Within a wide range of ACE2 expression levels, including the level observed in mouse pancreatic islets, overexpression of ADAM17 increases shed ACE2 and decreases cellular ACE2 levels. We provide a mathematical description of shed and cellular ACE2 activities as a function of the ADAM17 activity. The effect of ADAM17 on the cellular ACE2 content was relatively modest with an absolute control strength value less than 0.25 and approaching 0 at low ADAM17 activities. Although we found that ADAM17 and ACE2 are both expressed in pancreatic islets, the β-cell is not the major cell type expressing ACE2 in islets. During diabetes progression in 8-, 12-, and 15-week-old db/db mice, ACE2 mRNA and ACE2 activity levels in pancreatic islets were not decreased over time nor significantly decreased compared with nondiabetic db/m mice. Levels of ADAM17 mRNA and ADAM17 activity were also not significantly changed. Inhibiting basal ADAM17 activity in mouse islets failed to affect ACE2 levels. We conclude that whereas ADAM17 has the ability to shed ACE2, ADAM17 does not deplete ACE2 from pancreatic islets in diabetic db/db mice. PMID:26441236

  16. A Soluble Form of the Giant Cadherin Fat1 Is Released from Pancreatic Cancer Cells by ADAM10 Mediated Ectodomain Shedding

    PubMed Central

    Wojtalewicz, Nathalie; Klein-Scory, Susanne; Hahn, Stephan; Schmiegel, Wolff; Warnken, Uwe; Schnölzer, Martina; de Bock, Charles E.

    2014-01-01

    In pancreatic cancer, there is a clear unmet need to identify new serum markers for either early diagnosis, therapeutic stratification or patient monitoring. Proteomic analysis of tumor cell secretomes is a promising approach to indicate proteins released from tumor cells in vitro. Ectodomain shedding of transmembrane proteins has previously been shown to contribute significant fractions the tumor cell secretomes and to generate valuable serum biomarkers. Here we introduce a soluble form of the giant cadherin Fat1 as a novel biomarker candidate. Fat1 expression and proteolytic processing was analyzed by mass spectrometry and Western blotting using pancreatic cancer cell lines as compared to human pancreatic ductal epithelial cells. RNA expression in cancer tissues was assessed by in silico analysis of publically available microarray data. Involvement of ADAM10 (A Disintegrin and metalloproteinase domain-containing protein 10) in Fat1 ectodomain shedding was analyzed by chemical inhibition and knockdown experiments. A sandwich ELISA was developed to determine levels of soluble Fat1 in serum samples. In the present report we describe the release of high levels of the ectodomain of Fat1 cadherin into the secretomes of human pancreatic cancer cells in vitro, a process that is mediated by ADAM10. We confirm the full-length and processed heterodimeric form of Fat1 expressed on the plasma membrane and also show the p60 C-terminal transmembrane remnant fragment corresponding to the shed ectodomain. Fat1 and its sheddase ADAM10 are overexpressed in pancreatic adenocarcinomas and ectodomain shedding is also recapitulated in vivo leading to increased Fat1 serum levels in some pancreatic cancer patients. We suggest that soluble Fat1 may find an application as a marker for patient monitoring complementing carbohydrate antigen 19-9 (CA19-9). In addition, detailed analysis of the diverse processed protein isoforms of the candidate tumor suppressor Fat1 can also contribute to our

  17. Varroa destructor changes its cuticular hydrocarbons to mimic new hosts

    PubMed Central

    Le Conte, Y.; Huang, Z. Y.; Roux, M.; Zeng, Z. J.; Christidès, J.-P.; Bagnères, A.-G.

    2015-01-01

    Varroa destructor (Vd) is a honeybee ectoparasite. Its original host is the Asian honeybee, Apis cerana, but it has also become a severe, global threat to the European honeybee, Apis mellifera. Previous studies have shown that Varroa can mimic a host's cuticular hydrocarbons (HC), enabling the parasite to escape the hygienic behaviour of the host honeybees. By transferring mites between the two honeybee species, we further demonstrate that Vd is able to mimic the cuticular HC of a novel host species when artificially transferred to this new host. Mites originally from A. cerana are more efficient than mites from A. mellifera in mimicking HC of both A. cerana and A. mellifera. This remarkable adaptability may explain their relatively recent host-shift from A. cerana to A. mellifera. PMID:26041867

  18. ADAM33 is not essential for growth and development and does not modulate allergic asthma in mice.

    PubMed

    Chen, Chun; Huang, Xiaozhu; Sheppard, Dean

    2006-09-01

    A disintegrin and metalloprotease 33 (ADAM33) is a transmembrane protease and integrin ligand that has been identified as an asthma susceptibility gene product. To determine whether ADAM33 plays important roles in mammalian development and the modulation of allergic airway dysfunction, we generated ADAM33-null mice by gene targeting. ADAM33-null mice were born at expected Mendelian ratios, and both male and females developed normally and were fertile. No anatomical or histological abnormalities were detected in any tissues. In an animal model of allergic asthma, ADAM33-null mice showed normal allergen-induced airway hyperreactivity, immunoglobulin E production, mucus metaplasia, and airway inflammation. Our results demonstrate that ADAM33 is not essential for growth or reproduction in the mouse and does not modulate baseline or allergen-induced airway responsiveness.

  19. Manganese superoxide dismutase, MnSOD and its mimics

    PubMed Central

    Miriyala, Sumitra; Spasojevic, Ivan; Tovmasyan, Artak; Salvemini, Daniela; Vujaskovic, Zeljko; St. Clair, Daret; Batinic-Haberle, Ines

    2011-01-01

    Increased understanding of the role of mitochondria under physiological and pathological conditions parallels increased exploration of synthetic and natural compounds able to mimic MnSOD – endogenous mitochondrial antioxidant defense essential for the existence of virtually all aerobic organisms from bacteria to humans. This review describes most successful mitochondrially-targeted redox-active compounds, Mn porphyrins and MitoQ10 in detail, and briefly addresses several other compounds that are either catalysts of O2·− dismutation, or its non-catalytic scavengers, and that reportedly attenuate mitochondrial dysfunction. While not a true catalyst (SOD mimic) of O2·− dismutation, MitoQ10 oxidizes O2·− to O2 with a high rate constant. In vivo it is readily reduced to quinol, MitoQH2, which in turn reduces ONOO− to ·NO2, producing semiquinone radical that subsequently dismutes to MitoQ10 and MitoQH2, completing the “catalytic” cycle. In MitoQ10, the redox-active unit was coupled to alkyl chain and monocationic triphenylphosphonium ion in order to reach mitochondria. Mn porphyrin-based SOD mimics, however, were designed so that their multiple cationic charge and alkyl chains determine both their remarkable SOD potency and carry them into mitochondria. Several animal efficacy studies such as skin carcinogenesis and UVB-mediated mtDNA damage, and subcellular distribution studies of Saccharomyces cerevisiae and mouse heart provided unambiguous evidence that Mn porphyrins mimic the site and action of MnSOD, which in turn contributes to their efficacy in numerous in vitro and in vivo models of oxidative stress. Within a class of Mn porphyrins, lipophilic analogues are particularly effective for treating central nervous system injuries where mitochondria play key role. PMID:22198225

  20. MIMIC-III, a freely accessible critical care database

    PubMed Central

    Johnson, Alistair E.W.; Pollard, Tom J.; Shen, Lu; Lehman, Li-wei H.; Feng, Mengling; Ghassemi, Mohammad; Moody, Benjamin; Szolovits, Peter; Anthony Celi, Leo; Mark, Roger G.

    2016-01-01

    MIMIC-III (‘Medical Information Mart for Intensive Care’) is a large, single-center database comprising information relating to patients admitted to critical care units at a large tertiary care hospital. Data includes vital signs, medications, laboratory measurements, observations and notes charted by care providers, fluid balance, procedure codes, diagnostic codes, imaging reports, hospital length of stay, survival data, and more. The database supports applications including academic and industrial research, quality improvement initiatives, and higher education coursework. PMID:27219127

  1. Superoxide Dismutase Mimics: Chemistry, Pharmacology, and Therapeutic Potential

    PubMed Central

    Rebouças, Júlio S.; Spasojević, Ivan

    2010-01-01

    Abstract Oxidative stress has become widely viewed as an underlying condition in a number of diseases, such as ischemia–reperfusion disorders, central nervous system disorders, cardiovascular conditions, cancer, and diabetes. Thus, natural and synthetic antioxidants have been actively sought. Superoxide dismutase is a first line of defense against oxidative stress under physiological and pathological conditions. Therefore, the development of therapeutics aimed at mimicking superoxide dismutase was a natural maneuver. Metalloporphyrins, as well as Mn cyclic polyamines, Mn salen derivatives and nitroxides were all originally developed as SOD mimics. The same thermodynamic and electrostatic properties that make them potent SOD mimics may allow them to reduce other reactive species such as peroxynitrite, peroxynitrite-derived CO3·−, peroxyl radical, and less efficiently H2O2. By doing so SOD mimics can decrease both primary and secondary oxidative events, the latter arising from the inhibition of cellular transcriptional activity. To better judge the therapeutic potential and the advantage of one over the other type of compound, comparative studies of different classes of drugs in the same cellular and/or animal models are needed. We here provide a comprehensive overview of the chemical properties and some in vivo effects observed with various classes of compounds with a special emphasis on porphyrin-based compounds. Antioxid. Redox Signal. 13, 877–918. PMID:20095865

  2. Henry Adams’s Life of George Cabot Lodge: A Portrait of the Artist as an Alienated Man

    DTIC Science & Technology

    1994-07-20

    literary tradition, especially as had been handed down from Adams’s Puritan forebears. My aim is to present the most complete critical study of this...several critics have pointed to this book as evidence of Adams’s diminished talents--when a careful study of the book in fact demonstrates otherwise...critical studies have given more than cursory attention to the Life of Lodge: J. C. Levenson, The Mind and Art of Henry Adams (1957); George Hochfield

  3. A transforming Src mutant increases the bioavailability of EGFR-ligands via stimulation of the cell surface metalloproteinase ADAM17

    PubMed Central

    Maretzky, Thorsten; Zhou, Wenhui; Huang, Xin-Yun; Blobel, Carl P.

    2012-01-01

    ADAM17 (a disintegrin and metalloproteinase 17) is a cell-surface metalloproteinase that regulates signaling via the epidermal growth factor receptor (EGFR) and has important roles in diseases such as cancer and rheumatoid arthritis. ADAM17 can be activated by stimulation of several tyrosine kinase receptors, raising questions about whether oncogenic tyrosine kinases could also enhance EGFR signaling and activation of ERK via stimulation of ADAM17. The main goal of this study was to evaluate the role of Src in activating ADAM17. We provide evidence that a constitutively active transforming form of Src, the E378G mutant, as well as v-Src enhance ADAM17-mediated shedding of the EGFR-ligand TGFα. Moreover, we demonstrate that constitutive shedding of TGFα can be reduced by inhibition of Src in several cell lines, including COS7, MCF7, PAE and HaCaT cells. Src(E378G)-stimulated shedding of TGFα is abolished in Adam17−/− cells, but can be rescued by wild type ADAM17 and a mutant ADAM17 lacking its cytoplasmic domain. These findings demonstrate that ADAM17 is the principal TGFα sheddase that is activated by Src in a manner that does not require the cytoplasmic domain of ADAM17. Finally, we show that stimulation of ADAM17 by Src(E378G) leads to enhanced paracrine signaling via release of EGFR-ligands into the culture supernatant. These results raise the possibility that activation of ADAM17 by oncogenic forms of Src can aid in promoting tumorigenesis by enhancing signaling via the EGFR and ERK in an autocrine and paracrine manner. Enhanced autocrine signaling could further activate tumor cells expressing oncogenic mutants of Src, whereas paracrine signaling could stimulate EGFR and ERK signaling in surrounding non-transformed cells such as stromal cells, thereby contributing to crosstalk between tumor cells and stromal cells. PMID:20871631

  4. The disintegrin/metalloprotease ADAM 10 is essential for Notch signalling but not for alpha-secretase activity in fibroblasts.

    PubMed

    Hartmann, Dieter; de Strooper, Bart; Serneels, Lutgarde; Craessaerts, Katleen; Herreman, An; Annaert, Wim; Umans, Lieve; Lübke, Torben; Lena Illert, Anna; von Figura, Kurt; Saftig, Paul

    2002-10-01

    The metalloprotease ADAM 10 is an important APP alpha-secretase candidate, but in vivo proof of this is lacking. Furthermore, invertebrate models point towards a key role of the ADAM 10 orthologues Kuzbanian and sup-17 in Notch signalling. In the mouse, this function is, however, currently attributed to ADAM 17/TACE, while the role of ADAM 10 remains unknown. We have created ADAM 10-deficient mice. They die at day 9.5 of embryogenesis with multiple defects of the developing central nervous system, somites, and cardiovascular system. In situ hybridization revealed a reduced expression of the Notch target gene hes-5 in the neural tube and an increased expression of the Notch ligand dll-1, supporting an important role for ADAM 10 in Notch signalling in the vertebrates as well. Since the early lethality precluded the establishment of primary neuronal cultures, APPs alpha generation was analyzed in embryonic fibroblasts and found to be preserved in 15 out of 17 independently generated ADAM 10-deficient fibroblast cell lines, albeit at a quantitatively more variable level than in controls, whereas a severe reduction was found in only two cases. The variability was not due to differences in genetic background or to variable expression of the alternative alpha-secretase candidates ADAM 9 and ADAM 17. These results indicate, therefore, either a regulation between ADAMs on the post-translational level or that other, not yet known, proteases are able to compensate for ADAM 10 deficiency. Thus, the observed variability, together with recent reports on tissue-specific expression patterns of ADAMs 9, 10 and 17, points to the existence of tissue-specific 'teams' of different proteases exerting alpha-secretase activity.

  5. Monocyte ADAM17 promotes diapedesis during transendothelial migration: identification of steps and substrates targeted by metalloproteinases.

    PubMed

    Tsubota, Yoshiaki; Frey, Jeremy M; Tai, Phillip W L; Welikson, Robert E; Raines, Elaine W

    2013-04-15

    Despite expanded definition of the leukocyte adhesion cascade and mechanisms underlying individual steps, very little is known about regulatory mechanisms controlling sequential shifts between steps. We tested the hypothesis that metalloproteinases provide a mechanism to rapidly transition monocytes between different steps. Our study identifies diapedesis as a step targeted by metalloproteinase activity. Time-lapse video microscopy shows that the presence of a metalloproteinase inhibitor results in a doubling of the time required for human monocytes to complete diapedesis on unactivated or inflamed human endothelium, under both static and physiological-flow conditions. Thus, diapedesis is promoted by metalloproteinase activity. In contrast, neither adhesion of monocytes nor their locomotion over the endothelium is altered by metalloproteinase inhibition. We further demonstrate that metalloproteinase inhibition significantly elevates monocyte cell surface levels of integrins CD11b/CD18 (Mac-1), specifically during transendothelial migration. Interestingly, such alterations are not detected for other endothelial- and monocyte-adhesion molecules that are presumed metalloproteinase substrates. Two major transmembrane metalloproteinases, a disintegrin and metalloproteinase (ADAM)17 and ADAM10, are identified as enzymes that control constitutive cleavage of Mac-1. We further establish that knockdown of monocyte ADAM17, but not endothelial ADAM10 or ADAM17 or monocyte ADAM10, reproduces the diapedesis delay observed with metalloproteinase inhibition. Therefore, we conclude that monocyte ADAM17 facilitates the completion of transendothelial migration by accelerating the rate of diapedesis. We propose that the progression of diapedesis may be regulated by spatial and temporal cleavage of Mac-1, which is triggered upon interaction with endothelium.

  6. Analysis of mixed model in gear transmission based on ADAMS

    NASA Astrophysics Data System (ADS)

    Li, Xiufeng; Wang, Yabin

    2012-09-01

    The traditional method of mechanical gear driving simulation includes gear pair method and solid to solid contact method. The former has higher solving efficiency but lower results accuracy; the latter usually obtains higher precision of results while the calculation process is complex, also it is not easy to converge. Currently, most of the researches are focused on the description of geometric models and the definition of boundary conditions. However, none of them can solve the problems fundamentally. To improve the simulation efficiency while ensure the results with high accuracy, a mixed model method which uses gear tooth profiles to take the place of the solid gear to simulate gear movement is presented under these circumstances. In the process of modeling, build the solid models of the mechanism in the SolidWorks firstly; Then collect the point coordinates of outline curves of the gear using SolidWorks API and create fit curves in Adams based on the point coordinates; Next, adjust the position of those fitting curves according to the position of the contact area; Finally, define the loading conditions, boundary conditions and simulation parameters. The method provides gear shape information by tooth profile curves; simulates the mesh process through tooth profile curve to curve contact and offer mass as well as inertia data via solid gear models. This simulation process combines the two models to complete the gear driving analysis. In order to verify the validity of the method presented, both theoretical derivation and numerical simulation on a runaway escapement are conducted. The results show that the computational efficiency of the mixed model method is 1.4 times over the traditional method which contains solid to solid contact. Meanwhile, the simulation results are more closely to theoretical calculations. Consequently, mixed model method has a high application value regarding to the study of the dynamics of gear mechanism.

  7. TGF{beta} induces proHB-EGF shedding and EGFR transactivation through ADAM activation in gastric cancer cells

    SciTech Connect

    Ebi, Masahide; Kataoka, Hiromi; Shimura, Takaya; Kubota, Eiji; Hirata, Yoshikazu; Mizushima, Takashi; Mizoshita, Tsutomu; Tanaka, Mamoru; Mabuchi, Motoshi; Tsukamoto, Hironobu; Tanida, Satoshi; Kamiya, Takeshi; Higashiyama, Shigeki; Joh, Takashi

    2010-11-19

    Research highlights: {yields} TGF{beta} induces EGFR transactivation through proHB-EGF shedding by activated ADAM members in gastric cancer cells. {yields} TGF{beta} induces nuclear translocation of HB-EGF-CTF cleaved by ADAM members. {yields} TGF{beta} enhances cell growth by EGFR transactivation and HB-EGF-CTF nuclear translocation and ADAM inhibitors block these effects. {yields} Silencing of ADAM17 also blocks EGFR transactivation, HB-EGF-CTF nuclear translocation and cancer cell growth by TGF{beta}. {yields} ADAM17 may play a crucial role in this TGF{beta}-HB-EGF signal transduction. -- Abstract: Background and aims: Transforming growth factor-beta (TGF{beta}) is known to potently inhibit cell growth. Loss of responsiveness to TGF{beta} inhibition on cell growth is a hallmark of many types of cancer, yet its mechanism is not fully understood. Membrane-anchored heparin-binding EGF-like growth factor (proHB-EGF) ectodomain is cleaved by a disintegrin and metalloproteinase (ADAM) members and is implicated in epidermal growth factor receptor (EGFR) transactivation. Recently, nuclear translocation of the C-terminal fragment (CTF) of pro-HB-EGF was found to induce cell growth. We investigated the association between TGF{beta} and HB-EGF signal transduction via ADAM activation. Materials and methods: The CCK-8 assay in two gastric cancer cell lines was used to determine the effect for cell growth by TGF{beta}. The effect of two ADAM inhibitors was also evaluated. Induction of EGFR phosphorylation by TGF{beta} was analyzed and the effect of the ADAM inhibitors was also examined. Nuclear translocation of HB-EGF-CTF by shedding through ADAM activated by TGF{beta} was also analyzed. EGFR transactivation, HB-EGF-CTF nuclear translocation, and cell growth were examined under the condition of ADAM17 knockdown. Result: TGF{beta}-induced EGFR phosphorylation of which ADAM inhibitors were able to inhibit. TGF{beta} induced shedding of proHB-EGF allowing HB-EGF-CTF to

  8. Unsaturated Fatty Acids Drive Disintegrin and Metalloproteinase (ADAM)-dependent Cell Adhesion, Proliferation, and Migration by Modulating Membrane Fluidity*

    PubMed Central

    Reiss, Karina; Cornelsen, Isabell; Husmann, Matthias; Gimpl, Gerald; Bhakdi, Sucharit

    2011-01-01

    The disintegrin-metalloproteinases ADAM10 and ADAM17 mediate the release of several cell signaling molecules and cell adhesion molecules such as vascular endothelial cadherin or L-selectin affecting endothelial permeability and leukocyte transmigration. Dysregulation of ADAM activity may contribute to the pathogenesis of vascular diseases, but the mechanisms underlying the control of ADAM functions are still incompletely understood. Atherosclerosis is characterized by lipid plaque formation and local accumulation of unsaturated free fatty acids (FFA). Here, we show that unsaturated FFA increase ADAM-mediated substrate cleavage. We demonstrate that these alterations are not due to genuine changes in enzyme activity, but correlate with changes in membrane fluidity as revealed by measurement of 1,6-diphenyl-1,3,5-hexatriene fluorescence anisotropy and fluorescence recovery after photobleaching analyses. ELISA and immunoblot experiments conducted with granulocytes, endothelial cells, and keratinocytes revealed rapid increase of ectodomain shedding of ADAM10 and ADAM17 substrates upon membrane fluidization. Large amounts of unsaturated FFA may be liberated from cholesteryl esters in LDL that is entrapped in atherosclerotic lesions. Incubation of cells with thus modified LDL resulted in rapid cleavage of ADAM substrates with corresponding functional consequences on cell proliferation, cell migration, and endothelial permeability, events of high significance in atherogenesis. We propose that FFA represent critical regulators of ADAM function that may assume relevance in many biological settings through their influence on mobility of enzyme and substrate in lipid bilayers. PMID:21642425

  9. Unsaturated fatty acids drive disintegrin and metalloproteinase (ADAM)-dependent cell adhesion, proliferation, and migration by modulating membrane fluidity.

    PubMed

    Reiss, Karina; Cornelsen, Isabell; Husmann, Matthias; Gimpl, Gerald; Bhakdi, Sucharit

    2011-07-29

    The disintegrin-metalloproteinases ADAM10 and ADAM17 mediate the release of several cell signaling molecules and cell adhesion molecules such as vascular endothelial cadherin or L-selectin affecting endothelial permeability and leukocyte transmigration. Dysregulation of ADAM activity may contribute to the pathogenesis of vascular diseases, but the mechanisms underlying the control of ADAM functions are still incompletely understood. Atherosclerosis is characterized by lipid plaque formation and local accumulation of unsaturated free fatty acids (FFA). Here, we show that unsaturated FFA increase ADAM-mediated substrate cleavage. We demonstrate that these alterations are not due to genuine changes in enzyme activity, but correlate with changes in membrane fluidity as revealed by measurement of 1,6-diphenyl-1,3,5-hexatriene fluorescence anisotropy and fluorescence recovery after photobleaching analyses. ELISA and immunoblot experiments conducted with granulocytes, endothelial cells, and keratinocytes revealed rapid increase of ectodomain shedding of ADAM10 and ADAM17 substrates upon membrane fluidization. Large amounts of unsaturated FFA may be liberated from cholesteryl esters in LDL that is entrapped in atherosclerotic lesions. Incubation of cells with thus modified LDL resulted in rapid cleavage of ADAM substrates with corresponding functional consequences on cell proliferation, cell migration, and endothelial permeability, events of high significance in atherogenesis. We propose that FFA represent critical regulators of ADAM function that may assume relevance in many biological settings through their influence on mobility of enzyme and substrate in lipid bilayers.

  10. ADAM10 is expressed in human podocytes and found in urinary vesicles of patients with glomerular kidney diseases

    PubMed Central

    2010-01-01

    Background The importance of the Notch signaling in the development of glomerular diseases has been recently described. Therefore we analyzed in podocytes the expression and activity of ADAM10, one important component of the Notch signaling complex. Methods By Western blot, immunofluorescence and immunohistochemistry analysis we characterized the expression of ADAM10 in human podocytes, human urine and human renal tissue. Results We present evidence, that differentiated human podocytes possessed increased amounts of mature ADAM10 and released elevated levels of L1 adhesion molecule, one well known substrate of ADAM10. By using specific siRNA and metalloproteinase inhibitors we demonstrate that ADAM10 is involved in the cleavage of L1 in human podocytes. Injury of podocytes enhanced the ADAM10 mediated cleavage of L1. In addition, we detected ADAM10 in urinary podocytes from patients with kidney diseases and in tissue sections of normal human kidney. Finally, we found elevated levels of ADAM10 in urinary vesicles of patients with glomerular kidney diseases. Conclusions The activity of ADAM10 in human podocytes may play an important role in the development of glomerular kidney diseases. PMID:20070888

  11. A de novo designed 2[4Fe-4S] ferredoxin mimic mediates electron transfer.

    PubMed

    Roy, Anindya; Sommer, Dayn Joseph; Schmitz, Robert Arthur; Brown, Chelsea Lynn; Gust, Devens; Astashkin, Andrei; Ghirlanda, Giovanna

    2014-12-10

    [Fe-S] clusters, nature's modular electron transfer units, are often arranged in chains that support long-range electron transfer. Despite considerable interest, the design of biomimetic artificial systems emulating multicluster-binding proteins, with the final goal of integrating them in man-made oxidoreductases, remains elusive. Here, we report a novel bis-[4Fe-4S] cluster binding protein, DSD-Fdm, in which the two clusters are positioned within a distance of 12 Å, compatible with the electronic coupling necessary for efficient electron transfer. The design exploits the structural repeat of coiled coils as well as the symmetry of the starting scaffold, a homodimeric helical protein (DSD). In total, eight hydrophobic residues in the core of DSD were replaced by eight cysteine residues that serve as ligands to the [4Fe-4S] clusters. Incorporation of two [4Fe-4S] clusters proceeds with high yield. The two [4Fe-4S] clusters are located in the hydrophobic core of the helical bundle as characterized by various biophysical techniques. The secondary structure of the apo and holo proteins is conserved; further, the incorporation of clusters results in stabilization of the protein with respect to chemical denaturation. Most importantly, this de novo designed protein can mimic the function of natural ferredoxins: we show here that reduced DSD-Fdm transfers electrons to cytochrome c, thus generating the reduced cyt c stoichiometrically.

  12. Liver protective effect of ursodeoxycholic acid includes regulation of ADAM17 activity

    PubMed Central

    2013-01-01

    Background Ursodeoxycholic acid (UDCA) is used to treat primary biliary cirrhosis, intrahepatic cholestasis, and other cholestatic conditions. Although much has been learned about the molecular basis of the disease pathophysiology, our understanding of the effects of UDCA remains unclear. Possibly underlying its cytoprotective, anti-apoptotic, anti-oxidative effects, UDCA was reported to regulate the expression of TNFα and other inflammatory cytokines. However, it is not known if this effect involves also modulation of ADAM family of metalloproteinases, which are responsible for release of ectodomains of inflammatory cytokines from the cell surface. We hypothesized that UDCA modulates ADAM17 activity, resulting in amelioration of cholestasis in a murine model of bile duct ligation (BDL). Methods The effect of UDCA on ADAM17 activity was studied using the human liver hepatocellular carcinoma cell line HepG2. Untransfected cells or cells ectopically expressing human ADAM17 were cultured with or without UDCA and further activated using phorbol-12-myristate-13-acetate (PMA). The expression and release of ADAM17 substrates, TNFα, TGFα, and c-Met receptor (or its soluble form, sMet) were evaluated using ELISA and quantitative real-time (qRT) PCR. Immunoblotting analyses were conducted to evaluate expression and activation of ADAM17 as well as the level of ERK1/2 phosphorylation after UDCA treatment. The regulation of tissue inhibitor of metalloproteinases-1 (TIMP-1) by UDCA was studied using zymography and qRT-PCR. A mouse model of acute cholestasis was induced by common BDL technique, during which mice received daily orogastric gavage with either UDCA or vehicle only. Liver injury was quantified using alkaline phosphatase (ALP), relative liver weight, and confirmed by histological analysis. ADAM17 substrates in sera were assessed using a bead multiplex assay. Results UDCA decreases amount of shed TNFα, TGFα, and sMet in cell culture media and the phosphorylation of

  13. 50th anniversary of the discovery of ibuprofen: an interview with Dr Stewart Adams.

    PubMed

    Halford, Gayle M; Lordkipanidzé, Marie; Watson, Steve P

    2012-01-01

    2011 marks the 50th anniversary of the discovery of ibuprofen. This article is a focus on the personal reflections and career of Dr Stewart Adams OBE, the scientist whose research lead to the discovery of the cyclooxygenase inhibitor. When Dr Adams discovered ibuprofen, he was working as a pharmacologist in the Research Department for the Boots Pure Drug Company Ltd. Dr Adams was assigned to work on rheumatoid arthritis (RA) and chose in 1953 to search for a drug that would be effective in RA but would not be a corticosteroid. He was one of the first workers in this field that later became known as NSAIDs (Non-Steroidal Anti Inflammatory Drugs). In 1961, Dr Adams with John Nicholson, the organic chemist, filed a patent for the compound 2-(4-isobutylphenyl) propionic acid, later to become one of the most successful NSAIDs in the modern world, ibuprofen. In this article, Dr Adams gives his modest insight into the early stages and initial observations which led to this world-wide success.

  14. Pyrococcus Furiosus Genome Supplementary Data from the Adams Laboratory at the University of Georgia

    DOE Data Explorer

    Adams, Michael W.W.; Weinberg, Michael V.; Schut, Gerrit J.; Brehm, Scott; Datta, Susmitta; Zhou, J.

    The research in the Adams Laboratory focuses on the physiology of hyperthermophilic organisms with an emphasis on metal-containing enzymes in the hyperthermophilic marine archaeon Pyrococcus furiosus. Three of the many articles from this University of Georgia lab have supplementary materials that are available on the Adams Lab website. All three sets of data are Open Reading Frames (ORFs) used for DNA microarray experiments and the changes in signal intensities. The full citations for the three articles are: 1) Weinberg, M. V., Schut, G. J., Brehm, S., Datta, S. and Adams, M. W. W. (2005) Cold shock of a hyperthermophilic archaeon: Pyrococcus furiosus exhibits multiple responses to a suboptimal growth temperature with a key role for membrane-bound glycoproteins. J Bacteriol. 187, 336-348; 2) Schut, G. J., Brehm, S. D., Datta, S. and Adams, M. W. W. (2003) "Whole genome DNA microarray analysis of a hyperthermophile and an archaeon: Pyrococcus furiosus grown on carbohydrates or peptides" J. Bacteriol. 185, 3935-3947; Schut, G. J., Zhou, J. and Adams, M. W. W. (2001) "DNA microarray analysis of the hyperthermophilic archaeon Pyrococcus furiosus evidence for a new type of sulfur-reducing enzyme" J. Bacteriol. 183, 7027-7036. Note that these articles are copyrighted by the Journal of Bacteriology.

  15. Metal-based superoxide dismutase and catalase mimics reduce oxidative stress biomarkers and extend life span of Saccharomyces cerevisiae.

    PubMed

    Ribeiro, Thales de P; Fonseca, Fernanda L; de Carvalho, Mariana D C; Godinho, Rodrigo M da C; de Almeida, Fernando Pereira; Saint'Pierre, Tatiana D; Rey, Nicolás A; Fernandes, Christiane; Horn, Adolfo; Pereira, Marcos D

    2017-01-15

    Aging is a natural process characterized by several biological changes. In this context, oxidative stress appears as a key factor that leads cells and organisms to severe dysfunctions and diseases. To cope with reactive oxygen species and oxidative-related damage, there has been increased use of superoxide dismutase (SOD)/catalase (CAT) biomimetic compounds. Recently, we have shown that three metal-based compounds {[Fe(HPClNOL)Cl2]NO3, [Cu(HPClNOL)(CH3CN)](ClO4)2 and Mn(HPClNOL)(Cl)2}, harboring in vitro SOD and/or CAT activities, were critical for protection of yeast cells against oxidative stress. In this work, treating Saccharomyces cerevisiae with these SOD/CAT mimics (25.0 µM/1 h), we highlight the pivotal role of these compounds to extend the life span of yeast during chronological aging. Evaluating lipid and protein oxidation of aged cells, it becomes evident that these mimics extend the life expectancy of yeast mainly due to the reduction in oxidative stress biomarkers. In addition, the treatment of yeast cells with these mimics regulated the amounts of lipid droplet occurrence, consistent with the requirement and protection of lipids for cell integrity during aging. Concerning SOD/CAT mimics uptake, using inductively coupled plasma mass spectrometry, we add new evidence that these complexes, besides being bioabsorbed by S. cerevisiae cells, can also affect metal homeostasis. Finally, our work presents a new application for these SOD/CAT mimics, which demonstrate a great potential to be employed as antiaging agents. Taken together, these promising results prompt future studies concerning the relevance of administration of these molecules against the emerging aging-related diseases such as Parkinson's, Alzheimer's and Huntington's.

  16. Differentiating Childhood Stroke From Mimics in the Emergency Department

    PubMed Central

    Yock-Corrales, Adriana; Churilov, Leonid; Monagle, Paul; Donnan, Geoffrey A.; Babl, Franz E.

    2016-01-01

    Background and Purpose— Clinical identification of stroke in the pediatric emergency department is critical for improving access to hyperacute therapies. We identified key clinical features associated with childhood stroke or transient ischemic attack compared with mimics. Methods— Two hundred and eighty consecutive children presenting to the emergency department with mimics, prospectively recruited over 18 months from 2009 to 2010, were compared with 102 children with stroke or transient ischemic attack, prospectively/retrospectively recruited from 2003 to 2010. Results— Cerebrovascular diagnoses included arterial ischemic stroke (55), hemorrhagic stroke (37), and transient ischemic attack (10). Mimic diagnoses included migraine (84), seizures (46), Bell’s palsy (29), and conversion disorders (18). Being well in the week before presentation (odds ratio [OR] 5.76, 95% confidence interval [CI] 2.25–14.79), face weakness (OR 2.94, 95% CI 1.19–7.28), arm weakness (OR 8.66, 95% CI, 2.50–30.02), and inability to walk (OR 3.38, 95% CI 1.54–7.42) were independently associated with increased odds of stroke diagnosis. Other symptoms were independently associated with decreased odds of stroke diagnosis (OR 0.28, 95% CI 0.10–0.77). Associations were not observed between seizures or loss of consciousness. Factors associated with stroke differed by arterial and hemorrhagic subtypes. Conclusions— Being well in the week before presentation, inability to walk, face and arm weakness are associated with increased odds of stroke. The lack of positive or negative association between stroke and seizures or loss of consciousness is an important difference to adults. Pediatric stroke pathways and bedside tools need to factor in differences between children and adults and between stroke subtypes. PMID:27601378

  17. Generation 9 polyamidoamine dendrimer encapsulated platinum nanoparticle mimics catalase size, shape, and catalytic activity.

    PubMed

    Wang, Xinyu; Zhang, Yincong; Li, Tianfu; Tian, Wende; Zhang, Qiang; Cheng, Yiyun

    2013-04-30

    Poly(amidoamine) (PAMAM) encapsulated platinum nanoparticles were synthesized and used as catalase mimics. Acetylated generation 9 (Ac-G9) PAMAM dendrimer with a molecular size around 10 nm was used as a template to synthesize platinum nanoparticles. The feeding molar ratio of Pt(4+) and Ac-G9 is 2048, and the synthesized platinum nanoparticle (Ac-G9/Pt NP) has an average size of 3.3 nm. Ac-G9/Pt NP has a similar molecular size and globular shape with catalase (~11 nm). The catalytic activity of Ac-G9/Pt NP on the decomposition of H2O2 is approaching that of catalase at 37 °C. Ac-G9/Pt NP shows differential response to the changes of pH and temperature compared with catalase, which can be explained by different catalytic mechanisms of Ac-G9/Pt NP and catalase. Ac-G9/Pt NP also shows horseradish peroxidase activity and is able to scavenge free radicals such as di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH). Furthermore, Ac-G9/Pt NP shows excellent biocompatibility on different cell lines and can down-regulate H2O2-induced intracellular reactive oxygen species (ROS) in these cells. These results suggest that dendrimers are promising mimics of proteins with different sizes and Ac-G9/Pt NP can be used as an alternative candidate of catalase to decrease oxidation stress in cells.

  18. Diatom Mimics: Directing the Formation of Biosilica Nanoparticles by Controlled Folding of Lysine-Leucine Peptides

    PubMed Central

    Baio, Joe E.; Zane, Ariel; Jaeger, Vance; Roehrich, Adrienne M.; Lutz, Helmut; Pfaendtner, Jim; Drobny, Gary P.; Weidner, Tobias

    2015-01-01

    Silaffins, long chain polyamines, and other biomolecules found in diatoms are involved in the assembly of a large number of silica nanostructures under mild, ambient conditions. Nanofabrication researchers have sought to mimic the diatom's biosilica production capabilities by engineering proteins to resemble aspects of naturally occurring biomolecules. Such mimics can produce monodisperse biosilica nanospheres, but in vitro production of the variety of intricate biosilica nanostructures that compose the diatom frustule is not yet possible. In this study we demonstrate how LK peptides, composed solely of lysine (K) and leucine (L) amino acids arranged with varying hydrophobic periodicities, initiate the formation of different biosilica nanostructures in vitro. When L and K residues are arranged with a periodicity of 3.5 the α-helical form of the LK peptide produces monodisperse biosilica nanospheres. However, when the LK periodicity is changed to 3.0, corresponding to a 310 helix, the morphology of the nanoparticles changes to elongated rod-like structures. β-strand LK peptides with a periodicity of 2.0 induce wire-like silica morphologies. This study illustrates how the morphology of biosilica can be changed simply by varying the periodicity of polar and nonpolar amino acids. PMID:25285787

  19. cNMP-AMs mimic and dissect bacterial nucleotidyl cyclase toxin effects.

    PubMed

    Beckert, Ulrike; Grundmann, Manuel; Wolter, Sabine; Schwede, Frank; Rehmann, Holger; Kaever, Volkhard; Kostenis, Evi; Seifert, Roland

    2014-09-05

    In addition to the well-known second messengers cAMP and cGMP, mammalian cells contain the cyclic pyrimidine nucleotides cCMP and cUMP. The Pseudomonas aeruginosa toxin ExoY massively increases cGMP and cUMP in cells, whereas the Bordetella pertussis toxin CyaA increases cAMP and, to a lesser extent, cCMP. To mimic and dissect toxin effects, we synthesized cNMP-acetoxymethylesters as prodrugs. cNMP-AMs rapidly and effectively released the corresponding cNMP in cells. The combination of cGMP-AM plus cUMP-AM mimicked cytotoxicity of ExoY. cUMP-AM and cGMP-AM differentially activated gene expression. Certain cCMP and cUMP effects were independent of the known cNMP effectors protein kinases A and G and guanine nucleotide exchange factor Epac. In conclusion, cNMP-AMs are useful tools to mimic and dissect bacterial nucleotidyl cyclase toxin effects.

  20. Compartmentalization Approaches in Soft Matter Science: From Nanoreactor Development to Organelle Mimics.

    PubMed

    Schoonen, Lise; van Hest, Jan C M

    2016-02-10

    Compartmentalization is an essential feature found in living cells to ensure that biological processes occur without being affected by undesired external influences. Over the years many scientists have designed self-assembled soft matter structures that mimic these natural catalytic compartments. The rationale behind this research is threefold. First of all, compartmentalization leads to the creation of a secluded environment for the catalytic species, which solves compatibility issues and which can improve catalyst efficiency and selectivity. Secondly, nano- and micro-compartments are constructed with the aim to obtain microenvironments that more closely mimic the cellular architecture. These biomimetic platforms are used to attain a better understanding of how cellular processes are executed. Thirdly, natural design rules are applied to create biomolecular assemblies with unusual functionality, which for example are used as artificial organelles. Here, recent developments will be discussed regarding these compartmentalized catalytic systems, with a selected number of illustrative examples to demonstrate which strategies have been followed, and to show to what extent the ambitious goals of this field of science have been reached. The focus here is on the field of soft matter science, covering the wide spectrum from polymeric assemblies to protein nanocages.

  1. Diagnosis of Atopic Dermatitis: Mimics, Overlaps, and Complications

    PubMed Central

    Siegfried, Elaine C.; Hebert, Adelaide A.

    2015-01-01

    Atopic dermatitis (AD) is one of the most common skin diseases affecting infants and children. A smaller subset of adults has persistent or new-onset AD. AD is characterized by pruritus, erythema, induration, and scale, but these features are also typical of several other conditions that can mimic, coexist with, or complicate AD. These include inflammatory skin conditions, infections, infestations, malignancies, genetic disorders, immunodeficiency disorders, nutritional disorders, graft-versus-host disease, and drug eruptions. Familiarity of the spectrum of these diseases and their distinguishing features is critical for correct and timely diagnosis and optimal treatment. PMID:26239454

  2. The Mediated MIMIC Model for Understanding the Underlying Mechanism of DIF

    ERIC Educational Resources Information Center

    Cheng, Ying; Shao, Can; Lathrop, Quinn N.

    2016-01-01

    Due to its flexibility, the multiple-indicator, multiple-causes (MIMIC) model has become an increasingly popular method for the detection of differential item functioning (DIF). In this article, we propose the mediated MIMIC model method to uncover the underlying mechanism of DIF. This method extends the usual MIMIC model by including one variable…

  3. The MIMIC Method with Scale Purification for Detecting Differential Item Functioning

    ERIC Educational Resources Information Center

    Wang, Wen-Chung; Shih, Ching-Lin; Yang, Chih-Chien

    2009-01-01

    This study implements a scale purification procedure onto the standard MIMIC method for differential item functioning (DIF) detection and assesses its performance through a series of simulations. It is found that the MIMIC method with scale purification (denoted as M-SP) outperforms the standard MIMIC method (denoted as M-ST) in controlling…

  4. Adam M. Reid: APA/APAGS Award for Distinguished Graduate Student in Professional Psychology.

    PubMed

    2015-11-01

    The APA/APAGS Award for Distinguished Graduate Student in Professional Psychology is awarded on an annual basis by the APA Board of Professional Affairs (BPA) and the American Psychological Association of Graduate Students (APAGS) to a graduate student who has demonstrated outstanding practice and application of psychology. One of the 2015 award winners is Adam M. Reid, who received this award "for his community service, in which he has integrated the highest standards of professional psychological clinical practice and science." Adam's award citation, biography, and a selected bibliography are presented here.

  5. George Adams Junior and his 1789 book An essay on vision.

    PubMed

    Goss, David A

    2009-04-01

    English instrument maker George Adams Junior (1750-1795) published An Essay on Vision in 1789, with a second edition appearing in 1792. The 153 page book (157 pages in the second edition) presented material on structure of the eye and the basic nature of vision and vision conditions, with an emphasis on the proper use and choice of spectacles for the "long sighted" and the "short-sighted." A brief biographical sketch of Adams is given, and the contents of the book are discussed, with presentation of excerpts relating to general optometric principles. The excerpts can serve to illustrate the state of optometric knowledge in the late eighteenth century.

  6. 77 FR 64847 - Union Pacific Railroad Company-Abandonment Exemption-in Adams, Weld and Boulder Counties, Colo.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-23

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF TRANSPORTATION Surface Transportation Board Union Pacific Railroad Company--Abandonment Exemption--in Adams, Weld... near Eastlake to the end of the line at milepost 33.17 near Valmont, in Adams, Weld and...

  7. Problems with McAdams and Pals's (2006) Proposal of a Framework for an Integrative Theory of Personality

    ERIC Educational Resources Information Center

    Epstein, Seymour

    2007-01-01

    Comments on the original article "A New Big Five: Fundamental Principles for an Integrative Science of Personality," by Dan P. McAdams and Jennifer L. Pals (see record 2006-03947-002). Here, the current author begins with a critique of McAdams and Pals's (April 2006) five principles for a framework for an integrative theory of personality. The…

  8. A Reader Response to File and Adams's "The Reality, Robustness, and Possible Superiority of Incidental Vocabulary Acquisition"

    ERIC Educational Resources Information Center

    Mason, Beniko; Krashen, Stephen

    2010-01-01

    File and Adams (2010) conclude that their data confirm the superiority of form-focused vocabulary instruction over incidental acquisition. The authors of this response argue that File and Adams's data actually confirm the reality, robustness, and possible superiority of incidental acquisition. Their subjects heard two passages read to them that…

  9. Polo-like Kinase 2, a Novel ADAM17 Signaling Component, Regulates Tumor Necrosis Factor α Ectodomain Shedding*

    PubMed Central

    Schwarz, Jeanette; Schmidt, Stefanie; Will, Olga; Koudelka, Tomas; Köhler, Kaja; Boss, Melanie; Rabe, Björn; Tholey, Andreas; Scheller, Jürgen; Schmidt-Arras, Dirk; Schwake, Michael; Rose-John, Stefan; Chalaris, Athena

    2014-01-01

    ADAM17 (a disintegrin and metalloprotease 17) controls pro- and anti-inflammatory signaling events by promoting ectodomain shedding of cytokine precursors and cytokine receptors. Despite the well documented substrate repertoire of ADAM17, little is known about regulatory mechanisms, leading to substrate recognition and catalytic activation. Here we report a direct interaction of the acidophilic kinase Polo-like k