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Sample records for identify lacosamide receptors

  1. Lacosamide

    Science.gov (United States)

    ... Lacosamide is in a class of medications called anticonvulsants. It works by decreasing abnormal electrical activity in ... older (about 1 in 500 people) who took anticonvulsants like lacosamide to treat various conditions during clinical ...

  2. Chimeric opioid peptides: Tools for identifying opioid receptor types

    International Nuclear Information System (INIS)

    Xie, G.; Miyajima, A.; Yokota, T.; Arai, K.; Goldstein, A.

    1990-01-01

    The authors synthesized several chimeric [125J-labelled] peptides in which the N-terminal nine residues of dynorphin-32, a peptide selective for the κ opioid receptor, were replaced by opioid peptides selective for other opioid receptor types. Each chimeric peptide retained the high affinity and type selectivity characteristic of its N-terminal sequence. The common C-terminal two-thirds of the chimeric peptides served as an epitope recognized by the same monoclonal antibody. When bound to receptors on a cell surface or membrane preparation, these peptides could still bind specifically to the monoclonal antibody. These chimeric peptides should be useful for isolating μ, δ, and κ opioid receptors and for identifying opioid receptors on transfected cells in expression cloning procedures. The general approach using chimeric peptides should be applicable to other peptide receptors

  3. An Application Of Receptor Modeling To Identify Airborne Particulate ...

    African Journals Online (AJOL)

    An Application Of Receptor Modeling To Identify Airborne Particulate Sources In Lagos, Nigeria. FS Olise, OK Owoade, HB Olaniyi. Abstract. There have been no clear demarcations between industrial and residential areas of Lagos with focus on industry as the major source. There is need to identify potential source types in ...

  4. Identifying the receptor subtype selectivity of retinoid X and retinoic acid receptors via quantum mechanics.

    Science.gov (United States)

    Tsuji, Motonori; Shudo, Koichi; Kagechika, Hiroyuki

    2017-03-01

    Understanding and identifying the receptor subtype selectivity of a ligand is an important issue in the field of drug discovery. Using a combination of classical molecular mechanics and quantum mechanical calculations, this report assesses the receptor subtype selectivity for the human retinoid X receptor (hRXR) and retinoic acid receptor (hRAR) ligand-binding domains (LBDs) complexed with retinoid ligands. The calculated energies show good correlation with the experimentally reported binding affinities. The technique proposed here is a promising method as it reveals the origin of the receptor subtype selectivity of selective ligands.

  5. Knock-In Mice with NOP-eGFP Receptors Identify Receptor Cellular and Regional Localization.

    Science.gov (United States)

    Ozawa, Akihiko; Brunori, Gloria; Mercatelli, Daniela; Wu, Jinhua; Cippitelli, Andrea; Zou, Bende; Xie, Xinmin Simon; Williams, Melissa; Zaveri, Nurulain T; Low, Sarah; Scherrer, Grégory; Kieffer, Brigitte L; Toll, Lawrence

    2015-08-19

    The nociceptin/orphanin FQ (NOP) receptor, the fourth member of the opioid receptor family, is involved in many processes common to the opioid receptors including pain and drug abuse. To better characterize receptor location and trafficking, knock-in mice were created by inserting the gene encoding enhanced green fluorescent protein (eGFP) into the NOP receptor gene (Oprl1) and producing mice expressing a functional NOP-eGFP C-terminal fusion in place of the native NOP receptor. The NOP-eGFP receptor was present in brain of homozygous knock-in animals in concentrations somewhat higher than in wild-type mice and was functional when tested for stimulation of [(35)S]GTPγS binding in vitro and in patch-clamp electrophysiology in dorsal root ganglia (DRG) neurons and hippocampal slices. Inhibition of morphine analgesia was equivalent when tested in knock-in and wild-type mice. Imaging revealed detailed neuroanatomy in brain, spinal cord, and DRG and was generally consistent with in vitro autoradiographic imaging of receptor location. Multicolor immunohistochemistry identified cells coexpressing various spinal cord and DRG cellular markers, as well as coexpression with μ-opioid receptors in DRG and brain regions. Both in tissue slices and primary cultures, the NOP-eGFP receptors appear throughout the cell body and in processes. These knock-in mice have NOP receptors that function both in vitro and in vivo and appear to be an exceptional tool to study receptor neuroanatomy and correlate with NOP receptor function. The NOP receptor, the fourth member of the opioid receptor family, is involved in pain, drug abuse, and a number of other CNS processes. The regional and cellular distribution has been difficult to determine due to lack of validated antibodies for immunohistochemical analysis. To provide a new tool for the investigation of receptor localization, we have produced knock-in mice with a fluorescent-tagged NOP receptor in place of the native NOP receptor. These

  6. Serotonin 5-HT4 receptors and forebrain cholinergic system: receptor expression in identified cell populations.

    Science.gov (United States)

    Peñas-Cazorla, Raúl; Vilaró, M Teresa

    2015-11-01

    Activation of serotonin 5-HT4 receptors has pro-cognitive effects on memory performance. The proposed underlying neurochemical mechanism is the enhancement of acetylcholine release in frontal cortex and hippocampus elicited by 5-HT4 agonists. Although 5-HT4 receptors are present in brain areas related to cognition, e.g., hippocampus and cortex, the cellular localization of the receptors that might modulate acetylcholine release is unknown at present. We have analyzed, using dual label in situ hybridization, the cellular localization of 5-HT4 receptor mRNA in identified neuronal populations of the rat basal forebrain, which is the source of the cholinergic innervation to cortex and hippocampus. 5-HT4 receptor mRNA was visualized with isotopically labeled oligonucleotide probes, whereas cholinergic, glutamatergic, GABAergic and parvalbumin-synthesizing neurons were identified with digoxigenin-labeled oligonucleotide probes. 5-HT4 receptor mRNA was not detected in the basal forebrain cholinergic cell population. In contrast, basal forebrain GABAergic, parvalbumin synthesizing, and glutamatergic cells contained 5-HT4 receptor mRNA. Hippocampal and cortical glutamatergic neurons also express this receptor. These results indicate that 5-HT4 receptors are not synthesized by cholinergic cells, and thus would be absent from cholinergic terminals. In contrast, several non-cholinergic cell populations within the basal forebrain and its target hippocampal and cortical areas express these receptors and are thus likely to mediate the enhancement of acetylcholine release elicited by 5-HT4 agonists.

  7. Budget impact analysis of adjunctive therapy with lacosamide for partial-onset epileptic seizures in Belgium.

    Science.gov (United States)

    Simoens, Steven

    2011-01-01

    This study aims to compute the budget impact of lacosamide, a new adjunctive therapy for partial-onset seizures in epilepsy patients from 16 years of age who are uncontrolled and having previously used at least three anti-epileptic drugs from a Belgian healthcare payer perspective. The budget impact analysis compared the 'world with lacosamide' to the 'world without lacosamide' and calculated how a change in the mix of anti-epileptic drugs used to treat uncontrolled epilepsy would impact drug spending from 2008 to 2013. Data on the number of patients and on the market shares of anti-epileptic drugs were taken from Belgian sources and from the literature. Unit costs of anti-epileptic drugs originated from Belgian sources. The budget impact was calculated from two scenarios about the market uptake of lacosamide. The Belgian target population is expected to increase from 5333 patients in 2008 to 5522 patients in 2013. Assuming that the market share of lacosamide increases linearly over time and is taken evenly from all other anti-epileptic drugs (AEDs), the budget impact of adopting adjunctive therapy with lacosamide increases from €5249 (0.1% of reference drug budget) in 2008 to €242,700 (4.7% of reference drug budget) in 2013. Assuming that 10% of patients use standard AED therapy plus lacosamide, the budget impact of adopting adjunctive therapy with lacosamide is around €800,000-900,000 per year (or 16.7% of the reference drug budget). Adjunctive therapy with lacosamide would raise drug spending for this patient population by as much as 16.7% per year. However, this budget impact analysis did not consider the fact that lacosamide reduces costs of seizure management and withdrawal. The literature suggests that, if savings in other healthcare costs are taken into account, adjunctive therapy with lacosamide may be cost saving.

  8. Identifiability and error minimization of receptor model parameters with PET

    International Nuclear Information System (INIS)

    Delforge, J.; Syrota, A.; Mazoyer, B.M.

    1989-01-01

    The identifiability problem and the general framework for experimental design optimization are presented. The methodology is applied to the problem of the receptor-ligand model parameter estimation with dynamic positron emission tomography data. The first attempts to identify the model parameters from data obtained with a single tracer injection led to disappointing numerical results. The possibility of improving parameter estimation using a new experimental design combining an injection of the labelled ligand and an injection of the cold ligand (displacement experiment) has been investigated. However, this second protocol led to two very different numerical solutions and it was necessary to demonstrate which solution was biologically valid. This has been possible by using a third protocol including both a displacement and a co-injection experiment. (authors). 16 refs.; 14 figs

  9. Chimeric opioid peptides: tools for identifying opioid receptor types.

    OpenAIRE

    Xie, G X; Miyajima, A; Yokota, T; Arai, K; Goldstein, A

    1990-01-01

    We synthesized several chimeric peptides in which the N-terminal nine residues of dynorphin-32, a peptide selective for the kappa opioid receptor, were replaced by opioid peptides selective for other opioid receptor types. Each chimeric peptide retained the high affinity and type selectivity characteristic of its N-terminal sequence. The common C-terminal two-thirds of the chimeric peptides served as an epitope recognized by the same monoclonal antibody. When bound to receptors on a cell surf...

  10. Intravenous Lacosamide in Pediatric Status Epilepticus: An Open-Label Efficacy and Safety Study.

    Science.gov (United States)

    Poddar, Karan; Sharma, Rohan; Ng, Yu-Tze

    2016-08-01

    Lacosamide is an antiepilepsy drug approved by the Food and Drug Administration for patients aged 17 years and older for partial-onset seizures as monotherapy or adjunctive therapy. We reviewed the use of intravenous lacosamide in children aged less than 17 years with status epilepticus. Children who received at least one dose of intravenous lacosamide for status epilepticus at our tertiary care children's hospital from December 2011 to March 2014 were studied. Status epilepticus was defined as continuous seizure activity for longer than 20 minutes or two or more recurrent seizures without regaining baseline level of awareness. Efficacy was defined as seizure freedom or more than 50% reduction of seizures within 24 hours of administering lacosamide. Nine children with a mean age of 5.7 years (range: three months to 16 years) were included. The mean initial or loading dose was 8.7 mg/kg, with seven of nine patients receiving a dose of 10 mg/kg. The average total amount of intravenous lacosamide administered within the initial 24 hours was 13.8 mg/kg. Lacosamide was found to be efficacious in seven of nine (77.8%) patients. Four patients (44.4%) became seizure free. Two patients continued to have status epilepticus within 24 hours of lacosamide administration. Bradycardia was observed in one patient. In children with status epilepticus, intravenous lacosamide was efficacious in 78% of the patients and 44% become seizure free. In addition, no significant adverse reactions were observed. An appropriate safe, effective initial, or loading dose may be 10 mg/kg. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Lacosamide reduces HDAC levels in the brain and improves memory: Potential for treatment of Alzheimer's disease.

    Science.gov (United States)

    Bang, Shraddha R; Ambavade, Shirishkumar D; Jagdale, Priti G; Adkar, Prafulla P; Waghmare, Arun B; Ambavade, Prashant D

    2015-07-01

    Lacosamide, a histone deacetylase (HDAC) inhibitor, has been approved for the treatment of epilepsy. Some HDAC inhibitors have been proven effective for the treatment of memory disorders. The present investigation was designed to evaluate the effect of lacosamide on memory and brain HDAC levels. The effect on memory was evaluated in animals with scopolamine-induced amnesia using the elevated plus maze, object recognition test, and radial arm maze. The levels of acetylcholinesterase and HDAC in the cerebral cortex were evaluated. Lacosamide at doses of 10 and 30mg/kg significantly reduced the transfer latency in the elevated plus maze. Lacosamide at a dose of 30mg/kg significantly increased the time spent with a familiar object in the object recognition test at the 24h interval and decreased the time spent in the baited arm. Moreover, at this dose, the number of errors in the radial arm maze at 3 and 24h intervals was minimized and a reduction in the level of HDAC1, but not acetylcholinesterase, was observed in the cerebral cortex. These effects of lacosamide are equivalent to those of piracetam at a dose of 300mg/kg. These results suggest that lacosamide at a 30mg/kg dose improves disrupted memory, possibly by inhibiting HDAC, and could be used to treat amnesic symptoms of Alzheimer's disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Putative chemosensory receptors of the codling moth, Cydia pomonella, identified by antennal transcriptome analysis.

    Directory of Open Access Journals (Sweden)

    Jonas M Bengtsson

    Full Text Available The codling moth, Cydia pomonella, is an important fruit pest worldwide. As nocturnal animals, adults depend to a large extent on olfactory cues for detection of food and mates, and, for females, oviposition sites. In insects, odor detection is mediated by odorant receptors (ORs and ionotropic receptors (IRs, which ensure the specificity of the olfactory sensory neuron responses. In this study, our aim was to identify chemosensory receptors in the codling moth as a means to uncover new targets for behavioral interference. Using next-generation sequencing techniques, we identified a total of 43 candidate ORs, one gustatory receptor and 15 IRs in the antennal transcriptome. Through Blast and sequence similarity analyses we annotated the insect obligatory co-receptor ORco, five genes clustering in a conserved clade containing sex pheromone receptors, one homolog of the Bombyx mori female-enriched receptor BmorOR30 (but no homologs of the other B. mori female-enriched receptors and one gene clustering in the sugar receptor family. Among the candidate IRs, we identified homologs of the two highly conserved co-receptors IR8a and IR25a, and one homolog of an IR involved in phenylethyl amine detection in Drosophila. Our results open for functional characterization of the chemosensory receptors of C. pomonella, with potential for new or refined applications of semiochemicals for control of this pest insect.

  13. Intravenous lacosamide for treatment of absence status epilepticus in genetic generalized epilepsy: A case report and review of literature.

    Science.gov (United States)

    Reif, P S; Männer, A; Willems, L M; Kay, L; Zöllner, J P; Klein, K M; Rosenow, F; Strzelczyk, A

    2018-04-06

    Nearly 10 years after its introduction into the market, the significance of lacosamide in genetic generalized epilepsies is still unclear. Its new mode of action may qualify lacosamide as a therapeutic agent in this entity, but only a limited number of cases have been published so far. To describe the efficacy of lacosamide as treatment in a patient with the absence status epilepticus. We report on a 28-year-old woman with genetic generalized epilepsy who suffered recurrent absence status epilepticus during video-EEG-monitoring. After treatment failure of first- and second-line medication, lacosamide was administered. The outcome in this patient was evaluated, and a systematic literature review was performed for the use of lacosamide in the absence status epilepticus. After application of 400 mg lacosamide intravenously, the absence status epilepticus terminated within 30 minutes. No further seizures or epileptiform discharges reoccurred until the end of video-EEG-Monitoring 3 days later. The role of lacosamide as a therapeutic option in patients with the absence status epilepticus is unclear. Only two cases have been reported so far with conflicting results. Further randomized controlled studies are required to validate the relevance of lacosamide as treatment for status epilepticus in genetic generalized and the absence epilepsy. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Identifying neuropeptide and protein hormone receptors in Drosophila melanogaster by exploiting genomic data

    DEFF Research Database (Denmark)

    Hauser, Frank; Williamson, Michael; Cazzamali, Giuseppe

    2006-01-01

    insect genome, that of the fruitfly Drosophila melanogaster, was sequenced in 2000, and about 200 GPCRs have been annnotated in this model insect. About 50 of these receptors were predicted to have neuropeptides or protein hormones as their ligands. Since 2000, the cDNAs of most of these candidate...... receptors have been cloned and for many receptors the endogenous ligand has been identified. In this review, we will give an update about the current knowledge of all Drosophila neuropeptide and protein hormone receptors, and discuss their phylogenetic relationships. Udgivelsesdato: 2006-Feb...

  15. LAM study: Effects of lacosamide on behaviour and quality of life in patients with epilepsy.

    Science.gov (United States)

    Alfaro, A; Asensio, M; García-Escrivá, A; Medrano, V; Salom, J M; Tortosa, D; Palao, S; Lezcano, M; Berenguer, L; Navarro, M; Cerdán, M; Buendía, J F; Giner, J C

    2016-12-16

    Psychiatric comorbidities are common in epileptic patients, and evaluating the impact of antiepileptic drugs on patients' moods is therefore essential. The aim of this study is to assess the effects of lacosamide on behaviour and quality of life in people with epilepsy. We conducted a multicentre prospective observational study of poorly-controlled epileptic patients who received lacosamide as an adjuvant treatment. Patients were evaluated on 4 occasions during a 12-month period. The impact of lacosamide on patients' mood and quality of life was assessed with the Quality of Life in Epilepsy Inventory-10 (QOLIE-10), the Hospital Anxiety and Depression Scale (HADS), and the Barratt Impulsiveness Scale (BIS-11). As a secondary objective, we evaluated the effectiveness and safety of lacosamide. We included 55 patients with a mean age of 47.1±18.4 years. At baseline, 34.5% of the patients had psychiatric comorbidities; the mean number of crises in the previous month was 3.6±4.3. The QOLIE-10 and HADS scales revealed statistically significant improvements in patients with a poor baseline condition (anxiety, depression, and/or poor quality of life). The BIS-11 scale detected no impulsive behaviour during follow-up. After 12 months of treatment, 51.9% of the patients were seizure-free and 77.8% experienced a reduction of at least 50% in seizure frequency. Adverse effects were mild in most cases; lacosamide was discontinued in 10 patients (18.2%). Lacosamide is a safe and effective treatment option for patients with epilepsy and psychiatric comorbidities. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Potential ligand-binding residues in rat olfactory receptors identified by correlated mutation analysis

    Science.gov (United States)

    Singer, M. S.; Oliveira, L.; Vriend, G.; Shepherd, G. M.

    1995-01-01

    A family of G-protein-coupled receptors is believed to mediate the recognition of odor molecules. In order to identify potential ligand-binding residues, we have applied correlated mutation analysis to receptor sequences from the rat. This method identifies pairs of sequence positions where residues remain conserved or mutate in tandem, thereby suggesting structural or functional importance. The analysis supported molecular modeling studies in suggesting several residues in positions that were consistent with ligand-binding function. Two of these positions, dominated by histidine residues, may play important roles in ligand binding and could confer broad specificity to mammalian odor receptors. The presence of positive (overdominant) selection at some of the identified positions provides additional evidence for roles in ligand binding. Higher-order groups of correlated residues were also observed. Each group may interact with an individual ligand determinant, and combinations of these groups may provide a multi-dimensional mechanism for receptor diversity.

  17. Identifying plant cell-surface receptors: combining 'classical' techniques with novel methods.

    Science.gov (United States)

    Uebler, Susanne; Dresselhaus, Thomas

    2014-04-01

    Cell-cell communication during development and reproduction in plants depends largely on a few phytohormones and many diverse classes of polymorphic secreted peptides. The peptide ligands are bound at the cell surface of target cells by their membranous interaction partners representing, in most cases, either receptor-like kinases or ion channels. Although knowledge of both the extracellular ligand and its corresponding receptor(s) is necessary to describe the downstream signalling pathway(s), to date only a few ligand-receptor pairs have been identified. Several methods, such as affinity purification and yeast two-hybrid screens, have been used very successfully to elucidate interactions between soluble proteins, but most of these methods cannot be applied to membranous proteins. Experimental obstacles such as low concentration and poor solubility of membrane receptors, as well as instable transient interactions, often hamper the use of these 'classical' approaches. However, over the last few years, a lot of progress has been made to overcome these problems by combining classical techniques with new methodologies. In the present article, we review the most promising recent methods in identifying cell-surface receptor interactions, with an emphasis on success stories outside the field of plant research.

  18. Initial post marketing experience with lacosamide in adult patients with epilepsy.

    Science.gov (United States)

    Harden, Cynthia L; Cohn, Aaron; Lowe, Merredith; Serrano, Enrique

    2012-02-01

    The outcomes of adult epilepsy patients prescribed lacosamide for additional seizure control. Responders were defined as having at least a 50% decrease in seizure frequency Sixty-seven patients were evaluated. Forty-six out of 67 patients (69%) were responders. Twelve of 14 patients not taking sodium channel-acting AEDs were responders (86%) and 34/53 patients taking sodium channel-acting AEDs were responders (64%) (difference not significant). Copyright © 2011 Elsevier B.V. All rights reserved.

  19. HindIII identifies a two allele DNA polymorphism of the human cannabinoid receptor gene (CNR)

    Energy Technology Data Exchange (ETDEWEB)

    Caenazzo, L.; Hoehe, M.R.; Hsieh, W.T.; Berrettini, W.H.; Bonner, T.I.; Gershon, E.S. (National Inst. of Health, Bethesda, MD (United States))

    1991-09-11

    HCNR p5, a 0.9 kb BamHI/EcoRI fragment from the human cannabinoid receptor gene inserted into pUC19, was used as probe. The fragment is located in an intron approximately 14 kb 5{prime} of the initiation codon. This fragment is a clean single copy sequence by genomic blotting. Hybridization of human genomic DNA digested with HindIII identified a two allele RFLP with bands at 5.5 (A1) and 3.3 kb (A2). The human cannabinoid receptor gene has been genetically mapped in CEPH reference pedigrees to the centromeric/q region of chromosome 6. In situ hybridization localizes it to 6q14-q15. Codominant segregation has been observed in 26 informative two- and three-generation CEPH pedigrees and in 14 medium-sized disease families.

  20. Identifying a Mechanism for Crosstalk Between the Estrogen and Glucocorticoid Receptors | Center for Cancer Research

    Science.gov (United States)

    Estrogen has long been known to play important roles in the development and progression of breast cancer. Its receptor (ER), a member of the steroid receptor family, binds to estrogen response elements (EREs) in DNA and regulates gene transcription. More recently, another steroid receptor family member, the glucocorticoid receptor (GR), has been implicated in breast cancer

  1. Identifying novel targets of oncogenic EGF receptor signaling in lung cancer through global phosphoproteomics.

    Science.gov (United States)

    Zhang, Xu; Belkina, Natalya; Jacob, Harrys Kishore Charles; Maity, Tapan; Biswas, Romi; Venugopalan, Abhilash; Shaw, Patrick G; Kim, Min-Sik; Chaerkady, Raghothama; Pandey, Akhilesh; Guha, Udayan

    2015-01-01

    Mutations in the epidermal growth factor receptor (EGFR) kinase domain occur in 10-30% of lung adenocarcinoma and are associated with tyrosine kinase inhibitor (TKI) sensitivity. We sought to identify the immediate direct and indirect phosphorylation targets of mutant EGFRs in lung adenocarcinoma. We undertook SILAC strategy, phosphopeptide enrichment, and quantitative MS to identify dynamic changes of phosphorylation downstream of mutant EGFRs in lung adenocarcinoma cells harboring EGFR(L858R) and EGFR(L858R/T790M) , the TKI-sensitive, and TKI-resistant mutations, respectively. Top canonical pathways that were inhibited upon erlotinib treatment in sensitive cells, but not in the resistant cells include EGFR, insulin receptor, hepatocyte growth factor, mitogen-activated protein kinase, mechanistic target of rapamycin, ribosomal protein S6 kinase beta 1, and Janus kinase/signal transducer and activator of transcription signaling. We identified phosphosites in proteins of the autophagy network, such as ULK1 (S623) that is constitutively phosphorylated in these lung adenocarcinoma cells; phosphorylation is inhibited upon erlotinib treatment in sensitive cells, but not in resistant cells. Finally, kinase-substrate prediction analysis from our data indicated that substrates of basophilic kinases from, AGC and Calcium and calmodulin-dependent kinase groups, as well as STE group kinases were significantly enriched and those of proline-directed kinases from, CMGC and Casein kinase groups were significantly depleted among substrates that exhibited increased phosphorylation upon EGF stimulation and reduced phosphorylation upon TKI inhibition. This is the first study to date to examine global phosphorylation changes upon erlotinib treatment of lung adenocarcinoma cells and results from this study provide new insights into signaling downstream of mutant EGFRs in lung adenocarcinoma. All MS data have been deposited in the ProteomeXchange with identifier PXD001101 (http

  2. Androgen receptors and serum testosterone levels identify different subsets of postmenopausal breast cancers

    Directory of Open Access Journals (Sweden)

    Secreto Giorgio

    2012-12-01

    Full Text Available Abstract Background Androgen receptors (AR are frequently expressed in breast cancers, but their implication in cancer growth is still controversial. In the present study, we further investigated the role of the androgen/AR pathway in breast cancer development. Methods AR expression was evaluated by immunochemistry in a cohort of 528 postmenopausal breast cancer patients previously examined for the association of serum testosterone levels with patient and tumor characteristics. AR expression was classified according to the percentage of stained cells: AR-absent (0% and AR-poorly (1%-30%, AR-moderately (>30%-60%, and AR-highly (>60% positive. Results Statistical analysis was performed in 451 patients who experienced natural menopause. AR-high expression was significantly related with low histologic grade and estrogen receptor (ER- and progesterone receptor (PR-positive status (P trendP=0.022, although a trend across the AR expression categories was not present. When women defined by ER status were analyzed separately, regression analysis in the ER-positive group showed a significant association of high testosterone levels with AR-highly-positive expression (OR 1.86; 95% CI, 1.10-3.16, but the association was essentially due to patients greater than or equal to 65 years (OR 2.42; 95% CI, 1.22-4.82. In ER-positive group, elevated testosterone levels appeared also associated with AR-absent expression, although the small number of patients in this category limited the appearance of significant effects (OR 1.92; 95% CI, 0.73–5.02: the association was present in both age groups ( Conclusions The findings in the present study confirm that testosterone levels are a marker of hormone-dependent breast cancer and suggest that the contemporary evaluation of ER status, AR expression, and circulating testosterone levels may identify different subsets of cancers whose growth may be influenced by androgens.

  3. Lacosamide and Levetiracetam Have No Effect on Sharp-Wave Ripple Rate

    Czech Academy of Sciences Publication Activity Database

    Kudláček, Jan; Chvojka, Jan; Pošusta, Antonín; Kováčová, Ľubica; Hong, S.B.; Weiss, S.; Volná, K.; Marusič, P.; Otáhal, Jakub; Jiruška, Přemysl

    2017-01-01

    Roč. 8, Dec 21 (2017), č. článku 687. ISSN 1664-2295 R&D Projects: GA ČR(CZ) GA14-02634S; GA ČR(CZ) GA15-08565S; GA MZd(CZ) NV15-29835A; GA MZd(CZ) NV17-28427A Institutional support: RVO:67985823 Keywords : high-frequency oscillations * sharp-wave ripples * levetiracetam * lacosamide * antiepileptic drugs Subject RIV: FH - Neurology OBOR OECD: Neurosciences (including psychophysiology Impact factor: 3.552, year: 2016

  4. Shotgun glycomics of pig lung identifies natural endogenous receptors for influenza viruses.

    Science.gov (United States)

    Byrd-Leotis, Lauren; Liu, Renpeng; Bradley, Konrad C; Lasanajak, Yi; Cummings, Sandra F; Song, Xuezheng; Heimburg-Molinaro, Jamie; Galloway, Summer E; Culhane, Marie R; Smith, David F; Steinhauer, David A; Cummings, Richard D

    2014-06-03

    Influenza viruses bind to host cell surface glycans containing terminal sialic acids, but as studies on influenza binding become more sophisticated, it is becoming evident that although sialic acid may be necessary, it is not sufficient for productive binding. To better define endogenous glycans that serve as viral receptors, we have explored glycan recognition in the pig lung, because influenza is broadly disseminated in swine, and swine have been postulated as an intermediary host for the emergence of pandemic strains. For these studies, we used the technology of "shotgun glycomics" to identify natural receptor glycans. The total released N- and O-glycans from pig lung glycoproteins and glycolipid-derived glycans were fluorescently tagged and separated by multidimensional HPLC, and individual glycans were covalently printed to generate pig lung shotgun glycan microarrays. All viruses tested interacted with one or more sialylated N-glycans but not O-glycans or glycolipid-derived glycans, and each virus demonstrated novel and unexpected differences in endogenous N-glycan recognition. The results illustrate the repertoire of specific, endogenous N-glycans of pig lung glycoproteins for virus recognition and offer a new direction for studying endogenous glycan functions in viral pathogenesis.

  5. Implementation of a fluorescence-based screening assay identifies histamine H3 receptor antagonists clobenpropit and iodophenpropit as subunit-selective N-methyl-D-aspartate receptor antagonists

    DEFF Research Database (Denmark)

    Hansen, Kasper Bø; Mullasseril, Praseeda; Dawit, Sara

    2010-01-01

    N-Methyl-D-aspartate (NMDA) receptors are ligand-gated ion channels that mediate a slow, Ca(2+)-permeable component of excitatory synaptic transmission in the central nervous system and play a pivotal role in synaptic plasticity, neuronal development, and several neurological diseases. We describe...... a fluorescence-based assay that measures NMDA receptor-mediated changes in intracellular calcium in a BHK-21 cell line stably expressing NMDA receptor NR2D with NR1 under the control of a tetracycline-inducible promoter (Tet-On). The assay selectively identifies allosteric modulators by using supramaximal...

  6. Stability-indicating liquid chromatographic method for quantification of new anti-epileptic drug lacosamide in bulk and pharmaceutical formulation

    Directory of Open Access Journals (Sweden)

    Chhalotiya Usmangani K.

    2012-01-01

    Full Text Available An isocratic stability indicating reversed-phase liquid chromatographic determination was developed for the quantitative determination of lacosamide in the pharmaceutical dosage form. A Hypersil C-18, 4.5μm column with mobile phase containing acetonitrile-water (20:80, v/v was used. The flow rate was 1.0 mL min-1 and effluents were monitored at 258 nm. The retention time of lacosamide was 8.9 min. The method was found to be linear in the concentration range of 5-100 μg/ml and the recovery was found to be in the range of 99.15 - 100.09 %. The limit of detection and limit of quantification were found to be 2 μg/ml and 5 μg/ml, respectively. Lacosamide stock solutions were subjected to acid and alkali hydrolysis, chemical oxidation and dry heat degradation. The drug was found to be stable to the dry heat and acidic condition attempted. The proposed method was validated and successfully applied to the estimation of lacosamide in tablet dosage forms.

  7. The chemokine receptor CCR1 is identified in mast cell-derived exosomes.

    Science.gov (United States)

    Liang, Yuting; Qiao, Longwei; Peng, Xia; Cui, Zelin; Yin, Yue; Liao, Huanjin; Jiang, Min; Li, Li

    2018-01-01

    Mast cells are important effector cells of the immune system, and mast cell-derived exosomes carrying RNAs play a role in immune regulation. However, the molecular function of mast cell-derived exosomes is currently unknown, and here, we identify differentially expressed genes (DEGs) in mast cells and exosomes. We isolated mast cells derived exosomes through differential centrifugation and screened the DEGs from mast cell-derived exosomes, using the GSE25330 array dataset downloaded from the Gene Expression Omnibus database. Biochemical pathways were analyzed by Gene ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway on the online tool DAVID. DEGs-associated protein-protein interaction networks (PPIs) were constructed using the STRING database and Cytoscape software. The genes identified from these bioinformatics analyses were verified by qRT-PCR and Western blot in mast cells and exosomes. We identified 2121 DEGs (843 up and 1278 down-regulated genes) in HMC-1 cell-derived exosomes and HMC-1 cells. The up-regulated DEGs were classified into two significant modules. The chemokine receptor CCR1 was screened as a hub gene and enriched in cytokine-mediated signaling pathway in module one. Seven genes, including CCR1, CD9, KIT, TGFBR1, TLR9, TPSAB1 and TPSB2 were screened and validated through qRT-PCR analysis. We have achieved a comprehensive view of the pivotal genes and pathways in mast cells and exosomes and identified CCR1 as a hub gene in mast cell-derived exosomes. Our results provide novel clues with respect to the biological processes through which mast cell-derived exosomes modulate immune responses.

  8. An orphan viral TNF receptor superfamily member identified in lymphocystis disease virus.

    Science.gov (United States)

    Pontejo, Sergio M; Sánchez, Carolina; Martín, Rocío; Mulero, Victoriano; Alcami, Antonio; Alejo, Alí

    2013-06-07

    Lymphocystis disease virus (LCDV) is a large icosahedral dsDNA-containing virus of the Lymphocystivirus genus within the Iridoviridae family that can cause disease in more than 140 marine and freshwater fish species. While several isolates have been charcaterized and classified into distinct genotypes the complete genomic sequence is currently only available from two species, the LCDV-1, isolated from flounder (Platichtys flesus) in Europe and the LCDV-C, isolated from Japanese cultured flounder (Paralichthys olivaceus) in China. Analysis of the genome of LCDV-C showed it to encode a protein named LDVICp016 with similarities to the Tumour necrosis factor receptor (TNFR) superfamily with immunomodulatory potential. We have expressed and purified the recombinant protein LDVICp016 and screened for potential interaction partners using surface plasmon resonance. Commercially available human and mouse members of the TNF superfamily (TNFSF), along with a representative set of fish-derived TNFSF were tested.We have found the LDVICp016 protein to be secreted and we have identified a second viral TNFR encoded by ORF 095 of the same virus. None of the 42 tested proteins were found to interact with LDVICp016. We show that LDVICp016 is a secreted protein belonging to the TNF receptor family that may be part of a larger gene family in Lymphocystiviruses. While the ligand of this protein remains unknown, possibly due to the species specific nature of this interaction, further investigations into the potential role of this protein in the blockade of immune responses in its fish host are required.

  9. Lacosamide in the treatment of patients with epilepsy and intellectual disabilities: A long-term study of 136 patients.

    Science.gov (United States)

    Böttcher, Stefan; Lutz, Martin T; Mayer, Thomas

    2017-10-01

    This study aimed to analyze the retention rate of lacosamide (LCM) in patients with epilepsy and intellectual disabilities (IDs), to identify factors influencing retention rate, and to investigate the LCM retention rate with and without concomitant sodium channel blocker (SCB). We hypothesized that the retention rate of LCM with concomitant SCB would be lower than without SCB. Using the Kaplan-Meier estimator, we conducted a monocentric, retrospective, observational, open-label study to evaluate LCM retention rates in patients with IDs and drug-resistant epilepsy. In addition, the impact of therapy-related variables on the long-term retention of LCM was evaluated. One hundred thirty-six subjects with IDs and drug-resistant epilepsy were included (age 2-66 years); most patients had focal epilepsy. Long-term retention rates were 62.0% at 1 year, 43.7% at 2 years, and 29.1% at 3 and 4 years. Reasons for LCM discontinuation included insufficient therapeutic benefits (69%), adverse events (11%), or a combination of both factors (8%). The LCM retention rate was influenced by the number of background antiepileptic drugs (AEDs). An additional and independent influence of concomitant therapy with SCB on retention rate could not be confirmed. One of the major challenges in medically caring for patients with epilepsy and IDs is the high rate of drug resistance. However, there is a lack of evidence-based information about the efficacy and tolerability of AEDs in this population. It has been shown that concomitant SCB use is a key factor in increasing the risk of LCM failure in children with epilepsy. This finding has not been replicated in our predominantly adult sample of patients with IDs. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

  10. Identifying polymorphisms in the Rattus norvegicus D3 dopamine receptor gene and regulatory region

    NARCIS (Netherlands)

    Smits, B.M.; D'Souza, U.M.; Berezikov, E.; Cuppen, E.; Sluyter, F.

    2004-01-01

    The D(3) dopamine receptor has been implicated in several neuropsychiatric disorders, including schizophrenia, Parkinson's disease and addiction. Sequence variation in the D(3) gene can lead to subtle alteration in receptor structure or gene expression and thus to a different phenotype. In this

  11. Specific olfactory receptor populations projecting to identified glomeruli in the rat olfactory bulb.

    Science.gov (United States)

    Jastreboff, P J; Pedersen, P E; Greer, C A; Stewart, W B; Kauer, J S; Benson, T E; Shepherd, G M

    1984-08-01

    A critical gap exists in our knowledge of the topographical relationship between the olfactory epithelium and olfactory bulb. The present report describes the application to this problem of a method involving horseradish peroxidase conjugated to wheat germ agglutinin. This material was iontophoretically delivered to circumscribed glomeruli in the olfactory bulb and the characteristics and distribution of retrogradely labeled receptor cells were assessed. After discrete injections into small glomerular groups in the caudomedial bulb, topographically defined populations of receptor cells were labeled. Labeled receptor cell somata appeared at several levels within the epithelium. The receptor cell apical dendrites followed a tight helical course towards the surface of the epithelium. The data thus far demonstrate that functional units within the olfactory system may include not only glomeruli as previously suggested but, in addition, a corresponding matrix of receptor cells possessing functional and topographical specificity.

  12. Prevalence of mutations and functional analyses of melanocortin 4 receptor variants identified among 750 men with juvenile-onset obesity

    DEFF Research Database (Denmark)

    Larsen, Lesli H; Echwald, Søren Morgenthaler; Sørensen, Thorkild I A

    2005-01-01

    )) for mutations in MC4R. A total of 14 different mutations were identified of which two, Ala219Val and Leu325Phe, were novel variants. The variant receptor, Leu325Phe, was unable to bind [Nle4,d-Phe7]-alphaMSH, whereas the Ala219Val variant showed a significantly impaired melanotan II induction of cAMP, compared...

  13. Lacosamide and Levetiracetam Have No Effect on Sharp-Wave Ripple Rate.

    Science.gov (United States)

    Kudlacek, Jan; Chvojka, Jan; Posusta, Antonin; Kovacova, Lubica; Hong, Seung Bong; Weiss, Shennan; Volna, Kamila; Marusic, Petr; Otahal, Jakub; Jiruska, Premysl

    2017-01-01

    Pathological high-frequency oscillations are a novel marker used to improve the delineation of epileptogenic tissue and, hence, the outcome of epilepsy surgery. Their practical clinical utilization is curtailed by the inability to discriminate them from physiological oscillations due to frequency overlap. Although it is well documented that pathological HFOs are suppressed by antiepileptic drugs (AEDs), the effect of AEDs on normal HFOs is not well known. In this experimental study, we have explored whether physiological HFOs (sharp-wave ripples) of hippocampal origin respond to AED treatment. The results show that application of a single dose of levetiracetam or lacosamide does not reduce the rate of sharp-wave ripples. In addition, it seems that these new generation drugs do not negatively affect the cellular and network mechanisms involved in sharp-wave ripple generation, which may provide a plausible explanation for the absence of significant negative effects on cognitive functions of these drugs, particularly on memory.

  14. Dopamine1 receptors in rat kidneys identified with 125I-Sch 23982

    International Nuclear Information System (INIS)

    Felder, R.A.; Jose, P.A.

    1988-01-01

    Dopamine1 receptors were studied in rat kidney using the selective dopamine1 antagonist 125I-labeled Sch 23982. The specific binding of 125I-Sch 23982 (defined by 5 microM Sch 23390) to renal cortical homogenates incubated at room temperature was rapid, saturable with time and ligand concentration, and reversible. Analysis of Rosenthal plots revealed a single class of receptors with an apparent dissociation constant of 12.2 +/- 1.9 nM and maximum receptor density of 1.03 +/- 0.15 pmol/mg protein (n = 6). However, competition experiments with the dopamine1 antagonist Sch 23390 revealed a low- and high-affinity binding site with inhibition constants of 1 x 10(-6) and 1 x 10(-8) M, respectively. The competition experiments were also indicative of dopamine1 receptors with stereoselectivity noted for dopamine1 but not for dopamine2 antagonists. The inhibition constants for dopamine1 antagonists and agonists were two orders of magnitude greater in renal cortical than striatal homogenates. Different buffers affected striatal but not renal cortical binding. Autoradiographic studies revealed 125I-Sch 23982 binding in renal cortical but not medullary tissue. These studies confirm the presence of dopamine1 receptors in the cortex of the rat kidney

  15. Evaluation of Computational Docking to Identify Pregnane X Receptor Agonists in the ToxCast Database

    OpenAIRE

    Kortagere, Sandhya; Krasowski, Matthew D.; Reschly, Erica J.; Venkatesh, Madhukumar; Mani, Sridhar; Ekins, Sean

    2010-01-01

    Background The pregnane X receptor (PXR) is a key transcriptional regulator of many genes [e.g., cytochrome P450s (CYP2C9, CYP3A4, CYP2B6), MDR1] involved in xenobiotic metabolism and excretion. Objectives As part of an evaluation of different approaches to predict compound affinity for nuclear hormone receptors, we used the molecular docking program GOLD and a hybrid scoring scheme based on similarity weighted GoldScores to predict potential PXR agonists in the ToxCast database of pesticides...

  16. Peptides identify multiple hotspots within the ligand binding domain of the TNF receptor 2

    Directory of Open Access Journals (Sweden)

    Lennick Michael

    2003-01-01

    Full Text Available Abstract Background Hotspots are defined as the minimal functional domains involved in protein:protein interactions and sufficient to induce a biological response. Results Here we describe the use of complex and high diversity phage display libraries to isolate peptides (called Hotspot Ligands or HSPLs which sub-divide the ligand binding domain of the tumor necrosis factor receptor 2 (TNFR2; p75 into multiple hotspots. We have shown that these libraries could generate HSPLs which not only subdivide hotspots on protein and non-protein targets but act as agonists or antagonists. Using this approach, we generated peptides which were specific for human TNFR2, could be competed by the natural ligands, TNFα and TNFβ and induced an unexpected biological response in a TNFR2-specific manner. Conclusions To our knowledge, this is the first report describing the dissection of the TNFR2 into biologically active hotspots with the concomitant identification of a novel and unexpected biological activity.

  17. Structure modeling of all identified G protein-coupled receptors in the human genome.

    Science.gov (United States)

    Zhang, Yang; Devries, Mark E; Skolnick, Jeffrey

    2006-02-01

    G protein-coupled receptors (GPCRs), encoded by about 5% of human genes, comprise the largest family of integral membrane proteins and act as cell surface receptors responsible for the transduction of endogenous signal into a cellular response. Although tertiary structural information is crucial for function annotation and drug design, there are few experimentally determined GPCR structures. To address this issue, we employ the recently developed threading assembly refinement (TASSER) method to generate structure predictions for all 907 putative GPCRs in the human genome. Unlike traditional homology modeling approaches, TASSER modeling does not require solved homologous template structures; moreover, it often refines the structures closer to native. These features are essential for the comprehensive modeling of all human GPCRs when close homologous templates are absent. Based on a benchmarked confidence score, approximately 820 predicted models should have the correct folds. The majority of GPCR models share the characteristic seven-transmembrane helix topology, but 45 ORFs are predicted to have different structures. This is due to GPCR fragments that are predominantly from extracellular or intracellular domains as well as database annotation errors. Our preliminary validation includes the automated modeling of bovine rhodopsin, the only solved GPCR in the Protein Data Bank. With homologous templates excluded, the final model built by TASSER has a global C(alpha) root-mean-squared deviation from native of 4.6 angstroms, with a root-mean-squared deviation in the transmembrane helix region of 2.1 angstroms. Models of several representative GPCRs are compared with mutagenesis and affinity labeling data, and consistent agreement is demonstrated. Structure clustering of the predicted models shows that GPCRs with similar structures tend to belong to a similar functional class even when their sequences are diverse. These results demonstrate the usefulness and robustness

  18. Structure modeling of all identified G protein-coupled receptors in the human genome.

    Directory of Open Access Journals (Sweden)

    Yang Zhang

    2006-02-01

    Full Text Available G protein-coupled receptors (GPCRs, encoded by about 5% of human genes, comprise the largest family of integral membrane proteins and act as cell surface receptors responsible for the transduction of endogenous signal into a cellular response. Although tertiary structural information is crucial for function annotation and drug design, there are few experimentally determined GPCR structures. To address this issue, we employ the recently developed threading assembly refinement (TASSER method to generate structure predictions for all 907 putative GPCRs in the human genome. Unlike traditional homology modeling approaches, TASSER modeling does not require solved homologous template structures; moreover, it often refines the structures closer to native. These features are essential for the comprehensive modeling of all human GPCRs when close homologous templates are absent. Based on a benchmarked confidence score, approximately 820 predicted models should have the correct folds. The majority of GPCR models share the characteristic seven-transmembrane helix topology, but 45 ORFs are predicted to have different structures. This is due to GPCR fragments that are predominantly from extracellular or intracellular domains as well as database annotation errors. Our preliminary validation includes the automated modeling of bovine rhodopsin, the only solved GPCR in the Protein Data Bank. With homologous templates excluded, the final model built by TASSER has a global C(alpha root-mean-squared deviation from native of 4.6 angstroms, with a root-mean-squared deviation in the transmembrane helix region of 2.1 angstroms. Models of several representative GPCRs are compared with mutagenesis and affinity labeling data, and consistent agreement is demonstrated. Structure clustering of the predicted models shows that GPCRs with similar structures tend to belong to a similar functional class even when their sequences are diverse. These results demonstrate the usefulness

  19. Ionotropic Receptors Identified within the Tentacle of the Freshwater Snail Biomphalaria glabrata, an Intermediate Host of Schistosoma mansoni.

    Directory of Open Access Journals (Sweden)

    Di Liang

    Full Text Available Biomphalaria glabrata (B. glabrata is an air-breathing aquatic mollusc found in freshwater habitats across the Western Hemisphere. It is most well-known for its recognized capacity to act as a major intermediate host for Schistosoma mansoni, the human blood fluke parasite. Ionotropic receptors (IRs, a variant family of the ionotropic glutamate receptors (iGluR, have an evolutionary ancient function in detecting odors to initiate chemosensory signaling. In this study, we applied an array of methods towards the goal of identifying IR-like family members in B. glabrata, ultimately revealing two types, the iGluR and IR. Sequence alignment showed that three ligand-binding residues are conserved in most Biomphalaria iGluR sequences, while the IRs did exhibit a variable pattern, lacking some or all known glutamate-interactingresidues, supporting their distinct classification from the iGluRs. We show that B. glabrata contains 7 putative IRs, some of which are expressed within its chemosensory organs. To further investigate a role for the more ancient IR25a type in chemoreception, we tested its spatial distribution pattern within the snail cephalic tentacle by in situ hybridization. The presence of IR25a within presumptive sensory neurons supports a role for this receptor in olfactory processing, contributing to our understanding of the molecular pathways that are involved in Biomphalaria olfactory processing.

  20. Tartrazine and sunset yellow are xenoestrogens in a new screening assay to identify modulators of human oestrogen receptor transcriptional activity

    International Nuclear Information System (INIS)

    Axon, Andrew; May, Felicity E.B.; Gaughan, Luke E.; Williams, Faith M.; Blain, Peter G.; Wright, Matthew C.

    2012-01-01

    Primary biliary cirrhosis (PBC) is a cholestatic liver disease of unknown cause that occurs most frequently in post-menopausal women. Since the female sex hormone oestrogen can be cholestatic, we hypothesised that PBC may be triggered in part by chronic exposure to xenoestrogens (which may be more active on a background of low endogenous oestrogen levels seen in post-menopausal women). A reporter gene construct employing a synthetic oestrogen response element predicted to specifically interact with oestrogen receptors (ER) was constructed. Co-transfection of this reporter into an ER null cell line with a variety of nuclear receptor expression constructs indicated that the reporter gene was trans-activated by ERα and ERβ, but not by the androgen, thyroid, progesterone, glucocorticoid or vitamin D receptors. Chemicals linked to PBC were then screened for xenoestrogen activity in the human ERα-positive MCF-7 breast cancer cell line. Using this assay, the coal-derived food and cosmetic colourings – sunset yellow and tartrazine – were identified as novel human ERα activators, activating the human ER with an EC 50% concentration of 220 and 160 nM, respectively.

  1. Tartrazine and sunset yellow are xenoestrogens in a new screening assay to identify modulators of human oestrogen receptor transcriptional activity.

    Science.gov (United States)

    Axon, Andrew; May, Felicity E B; Gaughan, Luke E; Williams, Faith M; Blain, Peter G; Wright, Matthew C

    2012-08-16

    Primary biliary cirrhosis (PBC) is a cholestatic liver disease of unknown cause that occurs most frequently in post-menopausal women. Since the female sex hormone oestrogen can be cholestatic, we hypothesised that PBC may be triggered in part by chronic exposure to xenoestrogens (which may be more active on a background of low endogenous oestrogen levels seen in post-menopausal women). A reporter gene construct employing a synthetic oestrogen response element predicted to specifically interact with oestrogen receptors (ER) was constructed. Co-transfection of this reporter into an ER null cell line with a variety of nuclear receptor expression constructs indicated that the reporter gene was trans-activated by ERα and ERβ, but not by the androgen, thyroid, progesterone, glucocorticoid or vitamin D receptors. Chemicals linked to PBC were then screened for xenoestrogen activity in the human ERα-positive MCF-7 breast cancer cell line. Using this assay, the coal-derived food and cosmetic colourings--sunset yellow and tartrazine--were identified as novel human ERα activators, activating the human ER with an EC(50%) concentration of 220 and 160 nM, respectively. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  2. Identifying Medication Targets for Psychostimulant Addiction: Unraveling the Dopamine D3 Receptor Hypothesis

    Science.gov (United States)

    2016-01-01

    The dopamine D3 receptor (D3R) is a target for developing medications to treat substance use disorders. D3R-selective compounds with high affinity and varying efficacies have been discovered, providing critical research tools for cell-based studies that have been translated to in vivo models of drug abuse. D3R antagonists and partial agonists have shown especially promising results in rodent models of relapse-like behavior, including stress-, drug-, and cue-induced reinstatement of drug seeking. However, to date, translation to human studies has been limited. Herein, we present an overview and illustrate some of the pitfalls and challenges of developing novel D3R-selective compounds toward clinical utility, especially for treatment of cocaine abuse. Future research and development of D3R-selective antagonists and partial agonists for substance abuse remains critically important but will also require further evaluation and development of translational animal models to determine the best time in the addiction cycle to target D3Rs for optimal therapeutic efficacy. PMID:25826710

  3. Transcriptional profiling of human monocytes identifies the inhibitory receptor CD300a as regulator of transendothelial migration.

    Directory of Open Access Journals (Sweden)

    Sharang Ghavampour

    Full Text Available Local inflammatory responses are characterized by the recruitment of circulating leukocytes from the blood to sites of inflammation, a process requiring the directed migration of leukocytes across the vessel wall and hence a penetration of the endothelial lining. To identify underlying signalling events and novel factors involved in these processes we screened for genes differentially expressed in human monocytes following their adhesion to and passage through an endothelial monolayer. Functional annotation clustering of the genes identified revealed an overrepresentation of those associated with inflammation/immune response, in particular early monocyte to macrophage differentiation. Among the gene products so far not implicated in monocyte transendothelial migration was the inhibitory immune receptor CD300a. CD300a mRNA and protein levels were upregulated following transmigration and engagement of the receptor by anti-CD300a antibodies markedly reduced monocyte transendothelial migration. In contrast, siRNA mediated downregulation of CD300a in human monocytes increased their rate of migration. CD300a colocalized and cosedimented with actin filaments and, when activated, caused F-actin cytoskeleton alterations. Thus, monocyte transendothelial migration is accompanied by an elevation of CD300a which serves an inhibitory function possibly required for termination of the actual transmigration.

  4. Therapeutic Drug Monitoring of Lacosamide in Norway: Focus on Pharmacokinetic Variability, Efficacy and Tolerability.

    Science.gov (United States)

    Svendsen, Torleiv; Brodtkorb, Eylert; Baftiu, Arton; Burns, Margrete Larsen; Johannessen, Svein I; Johannessen Landmark, Cecilie

    2017-07-01

    Lacosamide (LCM) is a new antiepileptic drug (AED). Experience from therapeutic drug monitoring (TDM) in clinical practice is limited. The purpose of this study is to evaluate the pharmacokinetic variability of LCM in relation to efficacy and tolerability in patients with refractory epilepsy in a real-life setting. Variables included age, gender, daily doses and serum concentrations of LCM and other AEDs from the TDM-database at the National Center for Epilepsy in Norway. Clinical data regarding efficacy and tolerability were collected from medical records. The Norwegian Prescription Database (NorPD) was used to include population-based numbers of users. TDM-data from 344 patients were included. The median dose, serum concentration, and concentration/dose (C/D)-ratio of LCM was 350 (range 25-700) mg/day, 19.7 (range 8.1-56.2) µmol/L, and 0.06 (0.02-0.82) µmol/L/mg, respectively. Serum concentrations were reduced by 28% by concomitant use of enzyme inducers and increased by 30% in patients aged >65 years. Efficacy and tolerability were assessed in 227 patients: 29% had >50% seizure reduction (eight seizure free), 30% had no effect, and 44% reported adverse effects. In Norway, there were on average 500 patients per year using LCM in this period based on NorPD. The study demonstrated pharmacokinetic variability and use of TDM of LCM in Norway. Data were collected from multiple sources for improved pharmacovigilance. Serum concentrations were influenced by enzyme inducers and ageing, indicating the usefulness of TDM. Effect and tolerability were favorable within a suggested reference range of 10-40 µmol/L given drug-fasting conditions.

  5. Lacosamide as add-on treatment of focal symptomatic epilepsy in a patient with alcoholic liver cirrhosis

    Directory of Open Access Journals (Sweden)

    A. Romigi

    2014-01-01

    Full Text Available The occurrence of epileptic seizures in the presence of hepatic disease is not uncommon in clinical practice. Selecting an appropriate AED for patients affected by liver failure who have new-onset epileptic seizures can be challenging. We describe a 64-year-old man affected by liver cirrhosis. The patient developed partial epilepsy with secondary generalization because of an intracerebral hemorrhage in the left parieto-occipital regions. After the neurosurgery procedure, seizures reappeared and were initially managed with levetiracetam. After one month, the patient experienced clusters of seizures while on stable treatment with levetiracetam. Pregabalin as add-on was not tolerated; therefore, he received a low dose of phenobarbital as add-on treatment. The patient developed hepatic encephalopathy. Phenobarbital was immediately stopped, and oral lacosamide was added. A rapid recovery of encephalopathy with a 6-month seizure freedom was obtained. The patient died 6 months later because of progressive impairment of liver function. Lacosamide may represent an alternative to other AEDs in patients with liver failure; however, further prospective evaluation of its efficacy and safety in this clinical setting is needed.

  6. The functionalized amino acid (S-Lacosamide subverts CRMP2-mediated tubulin polymerization to prevent constitutive and activity-dependent increase in neurite outgrowth

    Directory of Open Access Journals (Sweden)

    Sarah M Wilson

    2014-07-01

    Full Text Available Activity-dependent neurite outgrowth is a highly complex, regulated process with important implications for neuronal circuit remodeling in development as well as in seizure-induced sprouting in epilepsy. Recent work has linked outgrowth to collapsin response mediator protein 2 (CRMP2, an intracellular phosphoprotein originally identified as axon guidance and growth cone collapse protein. The neurite outgrowth promoting function of CRMP2 is regulated by its phosphorylation state. In this study, depolarization (potassium chloride-driven activity increased the level of active CRMP2 by decreasing its phosphorylation by GSK3β via a reduction in priming by Cdk5. To determine the contribution of CRMP2 in activity-driven neurite outgrowth, we screened a limited set of compounds for their ability to reduce neurite outgrowth but not modify voltage-gated sodium channel (VGSC biophysical properties. This led to the identification of (S-lacosamide ((S-LCM, a stereoisomer of the clinically used antiepileptic drug (R-LCM (Vimpat®, as a novel tool for preferentially targeting CRMP2-mediated neurite outgrowth. Whereas (S-LCM was ineffective in targeting VGSCs, the presumptive pharmacological targets of (R-LCM, (S-LCM was more efficient than (R-LCM in subverting neurite outgrowth. Biomolecular interaction analyses revealed that (S-LCM bound to wildtype CRMP2 with low micromolar affinity, similar to (R-LCM. Through the use of this novel tool, the activity-dependent increase in neurite outgrowth observed following depolarization was characterized to be reliant on CRMP2 function. Knockdown of CRMP2 by siRNA in cortical neurons resulted in reduced CRMP2-dependent neurite outgrowth; incubation with (S-LCM phenocopied this effect. Other CRMP2-mediated processes were unaffected. (S-LCM subverted neurite outgrowth not by affecting the canonical CRMP2-tubulin association but rather by impairing the ability of CRMP2 to promote tubulin polymerization, events that are

  7. T cell differentiation stages identified by molecular and immunologic analysis of the T cell receptor complex in childhood lymphoblastic leukemia.

    Science.gov (United States)

    Mirro, J; Kitchingman, G; Behm, F G; Murphy, S B; Goorha, R M

    1987-03-01

    T cell differentiation was investigated by determining the relationship of T cell receptor (Ti) gene rearrangement and transcription to the expression of surface and cytoplasmic T3 antigen using blast cells from five children with acute lymphoblastic leukemia of thymic origin. Patterns of monoclonal antibody (MoAb) reactivity indicated that these cases were representative of the three recognized stages (I, II, III) of human thymocyte development. The T3 antigen, which becomes linked to the Ti to form a functional T cell receptor complex on mature thymocytes, was expressed on the cell surface in two cases (stage III). However, in the remaining three cases that were surface T3 negative (stages I and II), large amounts of T3 were identified in the cytoplasm by immunoperoxidase staining and flow cytometry. Leukemic blasts from all five patients showed rearranged genes encoding the beta-chain portion of the Ti heterodimer. RNA transcripts of Ti beta-chain genes were also evident in lymphoblasts from all five cases, but transcripts coding for the alpha-chain portion of Ti were found only in cases that expressed T3 on the cell surface. Thus the absence of surface T3 (and presumably Ti) coincides with the absence of Ti alpha-chain RNA, suggesting that transcription of alpha-chain genes is a critical regulatory event in the surface expression of the Ti-T3 complex. Leukemic T cells that rearrange and express Ti beta-chain genes but lack Ti alpha-chain messenger RNA (mRNA) may represent a stage of differentiation analogous to pre-B cells, where heavy-chain immunoglobulin (Ig) genes are rearranged and expressed but light-chain Ig genes are not expressed.

  8. Strategy to Identify and Test Putative Light-Sensitive Non-Opsin G-Protein-Coupled Receptors: A Case Study.

    Science.gov (United States)

    Faggionato, Davide; Serb, Jeanne M

    2017-08-01

    The rise of high-throughput RNA sequencing (RNA-seq) and de novo transcriptome assembly has had a transformative impact on how we identify and study genes in the phototransduction cascade of non-model organisms. But the advantage provided by the nearly automated annotation of RNA-seq transcriptomes may at the same time hinder the possibility for gene discovery and the discovery of new gene functions. For example, standard functional annotation based on domain homology to known protein families can only confirm group membership, not identify the emergence of new biochemical function. In this study, we show the importance of developing a strategy that circumvents the limitations of semiautomated annotation and apply this workflow to photosensitivity as a means to discover non-opsin photoreceptors. We hypothesize that non-opsin G-protein-coupled receptor (GPCR) proteins may have chromophore-binding lysines in locations that differ from opsin. Here, we provide the first case study describing non-opsin light-sensitive GPCRs based on tissue-specific RNA-seq data of the common bay scallop Argopecten irradians (Lamarck, 1819). Using a combination of sequence analysis and three-dimensional protein modeling, we identified two candidate proteins. We tested their photochemical properties and provide evidence showing that these two proteins incorporate 11-cis and/or all-trans retinal and react to light photochemically. Based on this case study, we demonstrate that there is potential for the discovery of new light-sensitive GPCRs, and we have developed a workflow that starts from RNA-seq assemblies to the discovery of new non-opsin, GPCR-based photopigments.

  9. A retinoic acid receptor cDNA probe (RAR2) identifies a moderately frequent RFLP on chromosome 17

    Energy Technology Data Exchange (ETDEWEB)

    Bale, A E; Weinberger, C; McBride, O W [National Cancer Institute, Bethesda, MD (USA)

    1988-08-11

    RAR2, a 0.72 kb EcoRI, PvuII fragment from the 5{prime} end of the retinoic acid receptor cDNA probe was isolated. PstI identifies a constant band at 0.87 kb and a simple two allele polymorphism with a band at either 3.3 kb (A1) or 2.9 kb (A2). In 38 random blood donors, the frequency of the 3.3 kb allele (A1) was 0.29 and of the 2.9 kb allele (A2) was 0.71. The polymorphic bands and the 0.87 kb constant band segregated with chromosome 17 in 88 human-rodent somatic cell hybrids. Co-dominant inheritance was shown in 35 individuals from 5 informative families. Weak constant bands at 6.4 kb, 4.0 kb and 1.4 kb did not cosegregate with the polymorphic bands in somatic cell hybrids and could be eliminated by increasing the wash stringency.

  10. Kinome screening for regulators of the estrogen receptor identifies LMTK3 as a new therapeutic target in breast cancer.

    Science.gov (United States)

    Giamas, Georgios; Filipović, Aleksandra; Jacob, Jimmy; Messier, Walter; Zhang, Hua; Yang, Dongyun; Zhang, Wu; Shifa, Belul Assefa; Photiou, Andrew; Tralau-Stewart, Cathy; Castellano, Leandro; Green, Andrew R; Coombes, R Charles; Ellis, Ian O; Ali, Simak; Lenz, Heinz-Josef; Stebbing, Justin

    2011-06-01

    Therapies targeting estrogen receptor α (ERα, encoded by ESR1) have transformed the treatment of breast cancer. However, large numbers of women relapse, highlighting the need for the discovery of new regulatory targets modulating ERα pathways. An siRNA screen identified kinases whose silencing alters the estrogen response including those previously implicated in regulating ERα activity (such as mitogen-activated protein kinase and AKT). Among the most potent regulators was lemur tyrosine kinase-3 (LMTK3), for which a role has not previously been assigned. In contrast to other modulators of ERα activity, LMTK3 seems to have been subject to Darwinian positive selection, a noteworthy result given the unique susceptibility of humans to ERα+ breast cancer. LMTK3 acts by decreasing the activity of protein kinase C (PKC) and the phosphorylation of AKT (Ser473), thereby increasing binding of forkhead box O3 (FOXO3) to the ESR1 promoter. LMTK3 phosphorylated ERα, protecting it from proteasomal degradation in vitro. Silencing of LMTK3 reduced tumor volume in an orthotopic mouse model and abrogated proliferation of ERα+ but not ERα- cells, indicative of its role in ERα activity. In human cancers, LMTK3 abundance and intronic polymorphisms were significantly associated with disease-free and overall survival and predicted response to endocrine therapies. These findings yield insights into the natural history of breast cancer in humans and reveal LMTK3 as a new therapeutic target.

  11. Three newly identified galectin homologues from triangle sail mussel (Hyriopsis cumingii) function as potential pattern-recognition receptors.

    Science.gov (United States)

    Zhao, Ling-Ling; Hui, Kaimin; Wang, Yu-Qing; Wang, Yue; Ren, Qian; Li, Xin-Cang

    2018-05-01

    Galactoside-binding lectins, also known as galectins, play crucial roles in innate immune response in invertebrates. In this study, three cDNA sequences from Hyriopsis cumingii were identified and collectively called HcGalec genes. Each of the three deduced HcGalec proteins contained a galactose-binding lectin domain or a GLECT domain. All the three HcGalec genes are mainly present in the hepatopancreas and gills, and their expression is induced at 24 h after bacterial challenge. Three recombinant HcGalec proteins can bind and agglutinate (Ca 2+ -dependent) various microorganisms, including Gram-positive and Gram-negative bacteria. These proteins can attach to mannan and peptidoglycan. Meanwhile, the expression of the three HcGalec genes in the gills were significantly down-regulated after dsRNA interference (HcGalec1-RNAi, HcGalec2-RNAi, and HcGalec3-RNAi) and Vibrio parahaemolyticus injection. The expression levels of some antimicrobial peptides, including lysozyme 1 and lysozyme 2, were also markedly decreased after dsRNA interference. Overall, these results suggested that these three HcGalec proteins may function as potential receptors participating in the innate immune responses of H. cumingii against bacterial infection. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Identifying Environmental Chemicals as Agonists of the Androgen Receptor by Applying a Quantitative High-throughput Screening Platform

    Science.gov (United States)

    Background: The androgen receptor (AR, NR3C4) is a nuclear receptor whose main function is acting as a transcription factor regulating gene expression for male sexual development and maintaining accessory sexual organ function. It is also a necessary component of female fertility...

  13. Expression microarray identifies the unliganded glucocorticoid receptor as a regulator of gene expression in mammary epithelial cells

    International Nuclear Information System (INIS)

    Ritter, Heather D; Mueller, Christopher R

    2014-01-01

    While glucocorticoids and the liganded glucocorticoid receptor (GR) have a well-established role in the maintenance of differentiation and suppression of apoptosis in breast tissue, the involvement of unliganded GR in cellular processes is less clear. Our previous studies implicated unliganded GR as a positive regulator of the BRCA1 tumour suppressor gene in the absence of glucocorticoid hormone, which suggested it could play a similar role in the regulation of other genes. An shRNA vector directed against GR was used to create mouse mammary cell lines with depleted endogenous levels of this receptor in order to further characterize the role of GR in breast cells. An expression microarray screen for targets of unliganded GR was performed using our GR-depleted cell lines maintained in the absence of glucocorticoids. Candidate genes positively regulated by unliganded GR were identified, classified by Gene Ontology and Ingenuity Pathway Analysis, and validated using quantitative real-time reverse transcriptase PCR. Chromatin immunoprecipitation and dual luciferase expression assays were conducted to further investigate the mechanism through which unliganded GR regulates these genes. Expression microarray analysis revealed 260 targets negatively regulated and 343 targets positively regulated by unliganded GR. A number of the positively regulated targets were involved in pro-apoptotic networks, possibly opposing the activity of liganded GR targets. Validation and further analysis of five candidates from the microarray indicated that two of these, Hsd11b1 and Ch25h, were regulated by unliganded GR in a manner similar to Brca1 during glucocorticoid treatment. Furthermore, GR was shown to interact directly with and upregulate the Ch25h promoter in the absence, but not the presence, of hydrocortisone (HC), confirming our previously described model of gene regulation by unliganded GR. This work presents the first identification of targets of unliganded GR. We propose that

  14. High-throughput sequencing of the T cell receptor β gene identifies aggressive early-stage mycosis fungoides.

    Science.gov (United States)

    de Masson, Adele; O'Malley, John T; Elco, Christopher P; Garcia, Sarah S; Divito, Sherrie J; Lowry, Elizabeth L; Tawa, Marianne; Fisher, David C; Devlin, Phillip M; Teague, Jessica E; Leboeuf, Nicole R; Kirsch, Ilan R; Robins, Harlan; Clark, Rachael A; Kupper, Thomas S

    2018-05-09

    Mycosis fungoides (MF), the most common cutaneous T cell lymphoma (CTCL) is a malignancy of skin-tropic memory T cells. Most MF cases present as early stage (stage I A/B, limited to the skin), and these patients typically have a chronic, indolent clinical course. However, a small subset of early-stage cases develop progressive and fatal disease. Because outcomes can be so different, early identification of this high-risk population is an urgent unmet clinical need. We evaluated the use of next-generation high-throughput DNA sequencing of the T cell receptor β gene ( TCRB ) in lesional skin biopsies to predict progression and survival in a discovery cohort of 208 patients with CTCL (177 with MF) from a 15-year longitudinal observational clinical study. We compared these data to the results in an independent validation cohort of 101 CTCL patients (87 with MF). The tumor clone frequency (TCF) in lesional skin, measured by high-throughput sequencing of the TCRB gene, was an independent prognostic factor of both progression-free and overall survival in patients with CTCL and MF in particular. In early-stage patients, a TCF of >25% in the skin was a stronger predictor of progression than any other established prognostic factor (stage IB versus IA, presence of plaques, high blood lactate dehydrogenase concentration, large-cell transformation, or age). The TCF therefore may accurately predict disease progression in early-stage MF. Early identification of patients at high risk for progression could help identify candidates who may benefit from allogeneic hematopoietic stem cell transplantation before their disease becomes treatment-refractory. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  15. Quantitative High-Throughput Screening and Orthogonal Assays to Identify Modulators of the Vitamin D Receptor (SETAC)

    Science.gov (United States)

    The Vitamin D nuclear receptor (VDR) is a selective, ligand-inducible transcription factor involved in numerous biological processes such as cell proliferation, differentiation, detoxification, calcium homeostasis, neurodevelopment, immune system regulation, cardiovascular functi...

  16. Effects of six APOA5 variants, identified in patients with severe hypertriglyceridemia, on in vitro lipoprotein lipase activity and receptor binding

    NARCIS (Netherlands)

    Dorfmeister, B.; Zeng, W. W.; Dichlberger, A.; Nilsson, S. K.; Schaap, F. G.; Hubacek, J. A.; Merkel, M.; Cooper, J. A.; Lookene, A.; Putt, W.; Whittall, R.; Lee, P. J.; Lins, L.; Delsaux, N.; Nierman, M.; Kuivenhoven, J. A.; Kastelein, J. J. P.; Vrablik, M.; Olivecrona, G.; Schneider, W. J.; Heeren, J.; Humphries, S. E.; Talmud, P. J.

    2008-01-01

    OBJECTIVE: The purpose of this study was to identify rare APOA5 variants in 130 severe hypertriglyceridemic patients by sequencing, and to test their functionality, since no patient recall was possible. METHODS AND RESULTS: We studied the impact in vitro on LPL activity and receptor binding of 3

  17. receptores

    Directory of Open Access Journals (Sweden)

    Salete Regina Daronco Benetti

    2006-01-01

    Full Text Available Se trata de un estudio etnográfico, que tuvo lo objetivo de interpretar el sistema de conocimiento y del significado atribuidos a la sangre referente a la transfusión sanguínea por los donadores y receptores de un banco de sangre. Para la colecta de las informaciones se observaron los participantes y la entrevista etnográfica se realizó el análisis de dominio, taxonómicos y temáticos. Los dominios culturales fueron: la sangre es vida: fuente de vida y alimento valioso; creencias religiosas: fuentes simbólicas de apoyos; donación sanguínea: un gesto colaborador que exige cuidarse, gratifica y trae felicidad; donación sanguínea: fuente simbólica de inseguridad; estar enfermo es una condición para realizar transfusión sanguínea; transfusión sanguínea: esperanza de vida; Creencias populares: transfusión sanguínea como riesgo para la salud; donadores de sangre: personas benditas; donar y recibir sangre: como significado de felicidad. Temática: “líquido precioso que origina, sostiene, modifica la vida, provoca miedo e inseguridad”.

  18. Subtle differences in molecular recognition between modified glycopeptide antibiotics and bacterial receptor peptides identified by electrospray ionization mass spectrometry

    DEFF Research Database (Denmark)

    Jørgensen, Thomas J. D.; Staroske, T; Roepstorff, P

    1999-01-01

    showing that electrospray ionization mass spectrometry (ESI-MS) can be used in the rapid quantitative analysis of mixtures of vancomycin-group antibiotics and their bacterial cell-wall receptors allowing the identification of even subtle differences in binding constants. Differences in affinities...

  19. Expression profiling of nuclear receptors in breast cancer identifies TLX as a mediator of growth and invasion in triple-negative breast cancer.

    Science.gov (United States)

    Lin, Meng-Lay; Patel, Hetal; Remenyi, Judit; Banerji, Christopher R S; Lai, Chun-Fui; Periyasamy, Manikandan; Lombardo, Ylenia; Busonero, Claudia; Ottaviani, Silvia; Passey, Alun; Quinlan, Philip R; Purdie, Colin A; Jordan, Lee B; Thompson, Alastair M; Finn, Richard S; Rueda, Oscar M; Caldas, Carlos; Gil, Jesus; Coombes, R Charles; Fuller-Pace, Frances V; Teschendorff, Andrew E; Buluwela, Laki; Ali, Simak

    2015-08-28

    The Nuclear Receptor (NR) superfamily of transcription factors comprises 48 members, several of which have been implicated in breast cancer. Most important is estrogen receptor-α (ERα), which is a key therapeutic target. ERα action is facilitated by co-operativity with other NR and there is evidence that ERα function may be recapitulated by other NRs in ERα-negative breast cancer. In order to examine the inter-relationships between nuclear receptors, and to obtain evidence for previously unsuspected roles for any NRs, we undertook quantitative RT-PCR and bioinformatics analysis to examine their expression in breast cancer. While most NRs were expressed, bioinformatic analyses differentiated tumours into distinct prognostic groups that were validated by analyzing public microarray data sets. Although ERα and progesterone receptor were dominant in distinguishing prognostic groups, other NR strengthened these groups. Clustering analysis identified several family members with potential importance in breast cancer. Specifically, RORγ is identified as being co-expressed with ERα, whilst several NRs are preferentially expressed in ERα-negative disease, with TLX expression being prognostic in this subtype. Functional studies demonstrated the importance of TLX in regulating growth and invasion in ERα-negative breast cancer cells.

  20. NMDAR hypofunction and somatostatin-expressing GABAergic interneurons and receptors: A newly identified correlation and its effects in schizophrenia

    Directory of Open Access Journals (Sweden)

    Fatemah Alherz

    2017-06-01

    Full Text Available This review investigates the association between N-methyl-d-Aspartate receptor (NMDAR hypofunction and somatostatin-expressing GABAergic interneurons (SST+ and how it contributes to the cognitive deficits observed in schizophrenia (SZ. This is based on evidence that NMDAR antagonists caused symptoms resembling SZ in healthy individuals. NMDAR hypofunction in GABAergic interneurons results in the modulation of the cortical network oscillation, particularly in the gamma range (30–80 Hz. These gamma-band oscillation (GBO abnormalities were found to lead to the cognitive deficits observed in the disorder. Postmortem mRNA studies have shown that SST decreased more significantly than any other biomarker in schizophrenic subjects. The functional role of Somatostatin (SST in the aetiology of SZ can be studied through its receptors. Genetic knockout studies in animal models in Huntington's disease (HD have shown that a specific SST receptor, SSTR2, is increased along with the increased NMDAR activity, with opposing patterns observed in SZ. A direct correlation between SSTR and NMDAR is hence inferred in this review with the hope of finding a potential new therapeutic target for the treatment of SZ and related neurological conditions.

  1. Receptor homodimerization plays a critical role in a novel dominant negative P2RY12 variant identified in a family with severe bleeding.

    Science.gov (United States)

    Mundell, S J; Rabbolini, D; Gabrielli, S; Chen, Q; Aungraheeta, R; Hutchinson, J L; Kilo, T; Mackay, J; Ward, C M; Stevenson, W; Morel-Kopp, M-C

    2018-01-01

    Essentials Three dominant variants for the autosomal recessive bleeding disorder type-8 have been described. To date, there has been no phenotype/genotype correlation explaining their dominant transmission. Proline plays an important role in P2Y12R ligand binding and signaling defects. P2Y12R homodimer formation is critical for the receptor function and signaling. Background Although inherited platelet disorders are still underdiagnosed worldwide, advances in molecular techniques are improving disease diagnosis and patient management. Objective To identify and characterize the mechanism underlying the bleeding phenotype in a Caucasian family with an autosomal dominant P2RY12 variant. Methods Full blood counts, platelet aggregometry, flow cytometry and western blotting were performed before next-generation sequencing (NGS). Detailed molecular analysis of the identified variant of the P2Y12 receptor (P2Y12R) was subsequently performed in mammalian cells overexpressing receptor constructs. Results All three referred individuals had markedly impaired ADP-induced platelet aggregation with primary wave only, despite normal total and surface P2Y12R expression. By NGS, a single P2RY12:c.G794C substitution (p.R265P) was identified in all affected individuals, and this was confirmed by Sanger sequencing. Mammalian cell experiments with the R265P-P2Y12R variant showed normal receptor surface expression versus wild-type (WT) P2Y12R. Agonist-stimulated R265P-P2Y12R function (both signaling and surface receptor loss) was reduced versus WT P2Y12R. Critically, R265P-P2Y12R acted in a dominant negative manner, with agonist-stimulated WT P2Y12R activity being reduced by variant coexpression, suggesting dramatic loss of WT homodimers. Importantly, platelet P2RY12 cDNA cloning and sequencing in two affected individuals also revealed three-fold mutant mRNA overexpression, decreasing even further the likelihood of WT homodimer formation. R265 located within extracellular loop 3 (EL3) is

  2. Standard Pathologic Features Can Be Used to Identify a Subset of Estrogen Receptor-Positive, HER2 Negative Patients Likely to Benefit from Neoadjuvant Chemotherapy.

    Science.gov (United States)

    Petruolo, Oriana A; Pilewskie, Melissa; Patil, Sujata; Barrio, Andrea V; Stempel, Michelle; Wen, Hannah Y; Morrow, Monica

    2017-09-01

    The benefit of neoadjuvant chemotherapy (NAC) in patients with estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) breast cancers and in invasive lobular carcinoma (ILC) is uncertain due to the low rates of pathologic complete response (pCR). The aim of this study was to determine if pathologic features can identify subsets likely to benefit from NAC. Patients with stage I-III ER+, HER2- breast cancer receiving NAC were retrospectively reviewed. Endpoints were downstaging to breast-conserving surgery (BCS) and nodal pCR after NAC. Patients were grouped by progesterone receptor (PR) status and grade/differentiation (high grade or poor [HP] vs. non-HP). From 2007 to 2016, 402 ER+/HER2- cancers in patients receiving NAC were identified. Median age was 50 years, 98% were clinical stage II-III, and 75% were cN+. Overall pCR rate was 5%; breast pCR in 7% and nodal pCR in 15% of cN+ patients (p benefit from NAC are those with PR- and HP tumors. Patients with ILC are unlikely to downstage in the breast or axilla compared with IDC. The use of these criteria can assist in defining the initial treatment approach.

  3. Disturbances of ligand potency and enhanced degradation of the human glycine receptor at affected positions G160 and T162 originally identified in patients suffering from hyperekplexia

    Directory of Open Access Journals (Sweden)

    Sinem eAtak

    2015-12-01

    Full Text Available Ligand-binding of Cys-loop receptors is determined by N-terminal extracellular loop structures from the plus as well as from the minus side of two adjacent subunits in the pentameric receptor complex. An aromatic residue in loop B of the glycine receptor (GlyR undergoes direct interaction with the incoming ligand via cation-π interactions. Recently we showed that mutated residues in loop B identified from human patients suffering from hyperekplexia disturb ligand-binding. Here, we exchanged the affected human residues by amino acids found in related members of the Cys-loop receptor family to determine the effects of side chain volume for ion channel properties. GlyR variants were characterized in vitro following transfection into cell lines in order to analyze protein expression, trafficking, degradation and ion channel function. GlyR α1 G160 mutations significantly decrease glycine potency arguing for a positional effect on neighboring aromatic residues and consequently glycine-binding within the ligand-binding pocket. Disturbed glycinergic inhibition due to T162 α1 mutations is an additive effect of affected biogenesis and structural changes within the ligand-binding site. Protein trafficking from the ER towards ER-Golgi intermediate compartment, the secretory Golgi pathways and finally the cell surface is largely diminished, but still sufficient to deliver ion channels that are functional at least at high glycine concentrations. The majority of T162 mutant protein accumulates in the ER and is conducted to ER-associated proteasomal degradation. Hence, G160 is an important determinant during glycine binding. In contrast, T162 assigns primarily receptor biogenesis whereas exchanges in functionality are secondary effects thereof.

  4. An in silico high-throughput screen identifies potential selective inhibitors for the non-receptor tyrosine kinase Pyk2

    Directory of Open Access Journals (Sweden)

    Meirson T

    2017-05-01

    Full Text Available Tomer Meirson, Abraham O Samson, Hava Gil-Henn Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, Israel Abstract: The non-receptor tyrosine kinase proline-rich tyrosine kinase 2 (Pyk2 is a critical mediator of signaling from cell surface growth factor and adhesion receptors to cell migration, proliferation, and survival. Emerging evidence indicates that signaling by Pyk2 regulates hematopoietic cell response, bone density, neuronal degeneration, angiogenesis, and cancer. These physiological and pathological roles of Pyk2 warrant it as a valuable therapeutic target for invasive cancers, osteoporosis, Alzheimer’s disease, and inflammatory cellular response. Despite its potential as a therapeutic target, no potent and selective inhibitor of Pyk2 is available at present. As a first step toward discovering specific potential inhibitors of Pyk2, we used an in silico high-throughput screening approach. A virtual library of six million lead-like compounds was docked against four different high-resolution Pyk2 kinase domain crystal structures and further selected for predicted potency and ligand efficiency. Ligand selectivity for Pyk2 over focal adhesion kinase (FAK was evaluated by comparative docking of ligands and measurement of binding free energy so as to obtain 40 potential candidates. Finally, the structural flexibility of a subset of the docking complexes was evaluated by molecular dynamics simulation, followed by intermolecular interaction analysis. These compounds may be considered as promising leads for further development of highly selective Pyk2 inhibitors. Keywords: virtual screen, efficiency metrics, MM-GBSA, molecular dynamics

  5. Cytokeratin 5 and estrogen receptor immunohistochemistry as a useful adjunct in identifying atypical papillary lesions on breast needle core biopsy.

    Science.gov (United States)

    Grin, Andrea; O'Malley, Frances P; Mulligan, Anna Marie

    2009-11-01

    The presence of atypical or usual epithelial proliferations within papillary breast lesions complicates their interpretation on core biopsy. We evaluated the combination of estrogen receptor (ER) and cytokeratin 5 (CK5) as an aid in the distinction of usual duct hyperplasia from atypical proliferations in this setting. Core biopsies from 185 papillary lesions were reviewed and of these, 82 cases were selected for immunohistochemical study based on the presence of an epithelial proliferation between the fibrovascular cores. Fifty-two cases were used as the test set and 30 cases, with subsequent surgical excision, were used as the validation set. The epithelial proliferation was evaluated for staining intensity and percentage of positive cells using CK5 and ER. Expression of both CK5 and ER was significantly different in nonatypical lesions when compared with atypical lesions (P90% of cells. CK5-high expression was defined as a mosaic pattern of staining in >20% of cells and CK5-low as absent or staining in hyperplasia from atypical proliferations within papillary lesions on core biopsy.

  6. Novel mutation identified in severe early-onset tumor necrosis factor receptor-associated periodic syndrome: a case report.

    Science.gov (United States)

    Radhakrishna, Suhas M; Grimm, Amy; Broderick, Lori

    2017-04-20

    Tumor Necrosis Factor Receptor-Associated Periodic Syndrome (TRAPS) is the second most common heritable autoinflammatory disease, typically presenting in pre-school aged children with fever episodes lasting 1-3 weeks. Systemic symptoms can include rash, myalgia, ocular inflammation, and serositis. Here we report an unusual presentation of TRAPS in a 7 month old girl who presented with only persistent fever. She was initially diagnosed with incomplete Kawasaki Disease and received IVIG and infliximab; however, her fevers quickly recurred. Subsequent testing revealed a urinary tract infection, but she did not improve despite appropriate therapy. As fever continued, she developed significant abdominal distension with imaging concerning for appendicitis, followed by hyperthermia and hemodynamic instability. Given her protracted clinical course and maternal history of a poorly defined inflammatory condition, an autoinflammatory disease was considered. Therapy with anakinra was initiated, resulting in rapid resolution of fever and normalization of inflammatory markers. She was found to have a previously unreported mutation, Thr90Pro, in the TNFRSF1A gene associated with TRAPS. This novel mutation was also confirmed in the patient's mother and maternal uncle. This report reviews a severe case of TRAPS in infancy associated with a novel mutation, Thr90Pro, in the TNFRSF1A gene, and emphasizes that autoinflammatory disease should be considered in the differential of infants with fever of unknown origin.

  7. Activity of the anticonvulsant lacosamide in experimental and human epilepsy via selective effects on slow Na+ channel inactivation.

    Science.gov (United States)

    Holtkamp, Dominik; Opitz, Thoralf; Niespodziany, Isabelle; Wolff, Christian; Beck, Heinz

    2017-01-01

    In human epilepsy, pharmacoresistance to antiepileptic drug therapy is a major problem affecting ~30% of patients with epilepsy. Many classical antiepileptic drugs target voltage-gated sodium channels, and their potent activity in inhibiting high-frequency firing has been attributed to their strong use-dependent blocking action. In chronic epilepsy, a loss of use-dependent block has emerged as a potential cellular mechanism of pharmacoresistance for anticonvulsants acting on voltage-gated sodium channels. The anticonvulsant drug lacosamide (LCM) also targets sodium channels, but has been shown to preferentially affect sodium channel slow inactivation processes, in contrast to most other anticonvulsants. We used whole-cell voltage clamp recordings in acutely isolated cells to investigate the effects of LCM on transient Na + currents. Furthermore, we used whole-cell current clamp recordings to assess effects on repetitive action potential firing in hippocampal slices. We show here that LCM exerts its effects primarily via shifting the slow inactivation voltage dependence to more hyperpolarized potentials in hippocampal dentate granule cells from control and epileptic rats, and from patients with epilepsy. It is important to note that this activity of LCM was maintained in chronic experimental and human epilepsy. Furthermore, we demonstrate that the efficacy of LCM in inhibiting high-frequency firing is undiminished in chronic experimental and human epilepsy. Taken together, these results show that LCM exhibits maintained efficacy in chronic epilepsy, in contrast to conventional use-dependent sodium channel blockers such as carbamazepine. They also establish that targeting slow inactivation may be a promising strategy for overcoming target mechanisms of pharmacoresistance. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

  8. Eslicarbazepine and the enhancement of slow inactivation of voltage-gated sodium channels: a comparison with carbamazepine, oxcarbazepine and lacosamide.

    Science.gov (United States)

    Hebeisen, Simon; Pires, Nuno; Loureiro, Ana I; Bonifácio, Maria João; Palma, Nuno; Whyment, Andrew; Spanswick, David; Soares-da-Silva, Patrício

    2015-02-01

    This study aimed at evaluating the effects of eslicarbazepine, carbamazepine (CBZ), oxcarbazepine (OXC) and lacosamide (LCM) on the fast and slow inactivated states of voltage-gated sodium channels (VGSC). The anti-epileptiform activity was evaluated in mouse isolated hippocampal slices. The anticonvulsant effects were evaluated in MES and the 6-Hz psychomotor tests. The whole-cell patch-clamp technique was used to investigate the effects of eslicarbazepine, CBZ, OXC and LCM on sodium channels endogenously expressed in N1E-115 mouse neuroblastoma cells. CBZ and eslicarbazepine exhibit similar concentration dependent suppression of epileptiform activity in hippocampal slices. In N1E-115 mouse neuroblastoma cells, at a concentration of 250 μM, the voltage dependence of the fast inactivation was not influenced by eslicarbazepine, whereas LCM, CBZ and OXC shifted the V0.5 value (mV) by -4.8, -12.0 and -16.6, respectively. Eslicarbazepine- and LCM-treated fast-inactivated channels recovered similarly to control conditions, whereas CBZ- and OXC-treated channels required longer pulses to recover. CBZ, eslicarbazepine and LCM shifted the voltage dependence of the slow inactivation (V0.5, mV) by -4.6, -31.2 and -53.3, respectively. For eslicarbazepine, LCM, CBZ and OXC, the affinity to the slow inactivated state was 5.9, 10.4, 1.7 and 1.8 times higher than to the channels in the resting state, respectively. In conclusion, eslicarbazepine did not share with CBZ and OXC the ability to alter fast inactivation of VGSC. Both eslicarbazepine and LCM reduce VGSC availability through enhancement of slow inactivation, but LCM demonstrated higher interaction with VGSC in the resting state and with fast inactivation gating. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. The 2.1 Å resolution structure of cyanopindolol-bound β1-adrenoceptor identifies an intramembrane Na+ ion that stabilises the ligand-free receptor.

    Directory of Open Access Journals (Sweden)

    Jennifer L Miller-Gallacher

    Full Text Available The β1-adrenoceptor (β1AR is a G protein-coupled receptor (GPCR that is activated by the endogenous agonists adrenaline and noradrenaline. We have determined the structure of an ultra-thermostable β1AR mutant bound to the weak partial agonist cyanopindolol to 2.1 Å resolution. High-quality crystals (100 μm plates were grown in lipidic cubic phase without the assistance of a T4 lysozyme or BRIL fusion in cytoplasmic loop 3, which is commonly employed for GPCR crystallisation. An intramembrane Na+ ion was identified co-ordinated to Asp872.50, Ser1283.39 and 3 water molecules, which is part of a more extensive network of water molecules in a cavity formed between transmembrane helices 1, 2, 3, 6 and 7. Remarkably, this water network and Na+ ion is highly conserved between β1AR and the adenosine A2A receptor (rmsd of 0.3 Å, despite an overall rmsd of 2.4 Å for all Cα atoms and only 23% amino acid identity in the transmembrane regions. The affinity of agonist binding and nanobody Nb80 binding to β1AR is unaffected by Na+ ions, but the stability of the receptor is decreased by 7.5°C in the absence of Na+. Mutation of amino acid side chains that are involved in the co-ordination of either Na+ or water molecules in the network decreases the stability of β1AR by 5-10°C. The data suggest that the intramembrane Na+ and associated water network stabilise the ligand-free state of β1AR, but still permits the receptor to form the activated state which involves the collapse of the Na+ binding pocket on agonist binding.

  10. Morphology and kainate-receptor immunoreactivity of identified neurons within the entorhinal cortex projecting to superior temporal sulcus in the cynomolgus monkey

    Science.gov (United States)

    Good, P. F.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

    1995-01-01

    Projections of the entorhinal cortex to the hippocampus are well known from the classical studies of Cajal (Ramon y Cajal, 1904) and Lorente de No (1933). Projections from the entorhinal cortex to neocortical areas are less well understood. Such connectivity is likely to underlie the consolidation of long-term declarative memory in neocortical sites. In the present study, a projection arising in layer V of the entorhinal cortex and terminating in a polymodal association area of the superior temporal gyrus has been identified with the use of retrograde tracing. The dendritic arbors of neurons giving rise to this projection were further investigated by cell filling and confocal microscopy with computer reconstruction. This analysis demonstrated that the dendritic arbor of identified projection neurons was largely confined to layer V, with the exception of a solitary, simple apical dendrite occasionally ascending to superficial laminae but often confined to the lamina dissecans (layer IV). Finally, immunoreactivity for glutamate-receptor subunit proteins GluR 5/6/7 of the dendritic arbor of identified entorhinal projection neurons was examined. The solitary apical dendrite of identified entorhinal projection neurons was prominently immunolabeled for GluR 5/6/7, as was the dendritic arbor of basilar dendrites of these neurons. The restriction of the large bulk of the dendritic arbor of identified entorhinal projection neurons to layer V implies that these neurons are likely to be heavily influenced by hippocampal output arriving in the deep layers of the entorhinal cortex. Immunoreactivity for GluR 5/6/7 throughout the dendritic arbor of such neurons indicates that this class of glutamate receptor is in a position to play a prominent role in mediating excitatory neurotransmission within hippocampal-entorhinal circuits.

  11. A protein-binding domain, EH, identified in the receptor tyrosine kinase substrate Eps15 and conserved in evolution

    DEFF Research Database (Denmark)

    Wong, W T; Schumacher, C; Salcini, A E

    1995-01-01

    In this report we structurally and functionally define a binding domain that is involved in protein association and that we have designated EH (for Eps15 homology domain). This domain was identified in the tyrosine kinase substrate Eps15 on the basis of regional conservation with several heteroge......In this report we structurally and functionally define a binding domain that is involved in protein association and that we have designated EH (for Eps15 homology domain). This domain was identified in the tyrosine kinase substrate Eps15 on the basis of regional conservation with several...... heterogeneous proteins of yeast and nematode. The EH domain spans about 70 amino acids and shows approximately 60% overall amino acid conservation. We demonstrated the ability of the EH domain to specifically bind cytosolic proteins in normal and malignant cells of mesenchymal, epithelial, and hematopoietic...... (for Eps15-related). Structural comparison of Eps15 and Eps15r defines a family of signal transducers possessing extensive networking abilities including EH-mediated binding and association with Src homology 3-containing proteins....

  12. Aberrant expression of the tyrosine kinase receptor EphA4 and the transcription factor twist in Sézary syndrome identified by gene expression analysis.

    Science.gov (United States)

    van Doorn, Remco; Dijkman, Remco; Vermeer, Maarten H; Out-Luiting, Jacoba J; van der Raaij-Helmer, Elisabeth M H; Willemze, Rein; Tensen, Cornelis P

    2004-08-15

    Sézary syndrome (Sz) is a malignancy of CD4+ memory skin-homing T cells and presents with erythroderma, lymphadenopathy, and peripheral blood involvement. To gain more insight into the molecular features of Sz, oligonucleotide array analysis was performed comparing gene expression patterns of CD4+ T cells from peripheral blood of patients with Sz with those of patients with erythroderma secondary to dermatitis and healthy controls. Using unsupervised hierarchical clustering gene, expression patterns of T cells from patients with Sz were classified separately from those of benign T cells. One hundred twenty-three genes were identified as significantly differentially expressed and had an average fold change exceeding 2. T cells from patients with Sz demonstrated decreased expression of the following hematopoietic malignancy-linked tumor suppressor genes: TGF-beta receptor II, Mxi1, Riz1, CREB-binding protein, BCL11a, STAT4, and Forkhead Box O1A. Moreover, the tyrosine kinase receptor EphA4 and the potentially oncogenic transcription factor Twist were highly and selectively expressed in T cells of patients with Sz. High expression of EphA4 and Twist was also observed in lesional skin biopsy specimens of a subset of patients with cutaneous T cell lymphomas related to Sz, whereas their expression was nearly undetectable in benign T cells or in skin lesions of patients with inflammatory dermatoses. Detection of EphA4 and Twist may be used in the molecular diagnosis of Sz and related cutaneous T-cell lymphomas. Furthermore, the membrane-bound EphA4 receptor may serve as a target for directed therapeutic intervention.

  13. Transcriptome profiling of equine vitamin E deficient neuroaxonal dystrophy identifies upregulation of liver X receptor target genes

    Science.gov (United States)

    Finno, Carrie J.; Bordbari, Matthew H.; Valberg, Stephanie J.; Lee, David; Herron, Josi; Hines, Kelly; Monsour, Tamer; Scott, Erica; Bannasch, Danika L.; Mickelson, James; Xu, Libin

    2016-01-01

    Specific spontaneous heritable neurodegenerative diseases have been associated with lower serum and cerebrospinal fluid α-tocopherol (α-TOH) concentrations. Equine neuroaxonal dystrophy (eNAD) has similar histologic lesions to human ataxia with vitamin E deficiency caused by mutations in the α-TOH transfer protein gene (TTPA). Mutations in TTPA are not present with eNAD and the molecular basis remains unknown. Given the neuropathologic phenotypic similarity of the conditions, we assessed the molecular basis of eNAD by global transcriptome sequencing of the cervical spinal cord. Differential gene expression analysis identified 157 significantly (FDRmedulla oblongata of eNAD horses. Evidence of LXR activation supports a role for modulation of oxysterol-dependent LXR transcription factor activity by tocopherols. We hypothesize that the protective role of α-TOH in eNAD may reside in its ability to prevent oxysterol accumulation and subsequent activation of the LXR in order to decrease lipid peroxidation associated neurodegeneration. PMID:27751910

  14. iNR-PhysChem: a sequence-based predictor for identifying nuclear receptors and their subfamilies via physical-chemical property matrix.

    Directory of Open Access Journals (Sweden)

    Xuan Xiao

    Full Text Available Nuclear receptors (NRs form a family of ligand-activated transcription factors that regulate a wide variety of biological processes, such as homeostasis, reproduction, development, and metabolism. Human genome contains 48 genes encoding NRs. These receptors have become one of the most important targets for therapeutic drug development. According to their different action mechanisms or functions, NRs have been classified into seven subfamilies. With the avalanche of protein sequences generated in the postgenomic age, we are facing the following challenging problems. Given an uncharacterized protein sequence, how can we identify whether it is a nuclear receptor? If it is, what subfamily it belongs to? To address these problems, we developed a predictor called iNR-PhysChem in which the protein samples were expressed by a novel mode of pseudo amino acid composition (PseAAC whose components were derived from a physical-chemical matrix via a series of auto-covariance and cross-covariance transformations. It was observed that the overall success rate achieved by iNR-PhysChem was over 98% in identifying NRs or non-NRs, and over 92% in identifying NRs among the following seven subfamilies: NR1--thyroid hormone like, NR2--HNF4-like, NR3--estrogen like, NR4--nerve growth factor IB-like, NR5--fushi tarazu-F1 like, NR6--germ cell nuclear factor like, and NR0--knirps like. These rates were derived by the jackknife tests on a stringent benchmark dataset in which none of protein sequences included has ≥60% pairwise sequence identity to any other in a same subset. As a user-friendly web-server, iNR-PhysChem is freely accessible to the public at either http://www.jci-bioinfo.cn/iNR-PhysChem or http://icpr.jci.edu.cn/bioinfo/iNR-PhysChem. Also a step-by-step guide is provided on how to use the web-server to get the desired results without the need to follow the complicated mathematics involved in developing the predictor. It is anticipated that iNR-PhysChem may

  15. T cell receptor sequencing of early-stage breast cancer tumors identifies altered clonal structure of the T cell repertoire.

    Science.gov (United States)

    Beausang, John F; Wheeler, Amanda J; Chan, Natalie H; Hanft, Violet R; Dirbas, Frederick M; Jeffrey, Stefanie S; Quake, Stephen R

    2017-11-28

    Tumor-infiltrating T cells play an important role in many cancers, and can improve prognosis and yield therapeutic targets. We characterized T cells infiltrating both breast cancer tumors and the surrounding normal breast tissue to identify T cells specific to each, as well as their abundance in peripheral blood. Using immune profiling of the T cell beta-chain repertoire in 16 patients with early-stage breast cancer, we show that the clonal structure of the tumor is significantly different from adjacent breast tissue, with the tumor containing ∼2.5-fold greater density of T cells and higher clonality compared with normal breast. The clonal structure of T cells in blood and normal breast is more similar than between blood and tumor, and could be used to distinguish tumor from normal breast tissue in 14 of 16 patients. Many T cell sequences overlap between tissue and blood from the same patient, including ∼50% of T cells between tumor and normal breast. Both tumor and normal breast contain high-abundance "enriched" sequences that are absent or of low abundance in the other tissue. Many of these T cells are either not detected or detected with very low frequency in the blood, suggesting the existence of separate compartments of T cells in both tumor and normal breast. Enriched T cell sequences are typically unique to each patient, but a subset is shared between many different patients. We show that many of these are commonly generated sequences, and thus unlikely to play an important role in the tumor microenvironment. Copyright © 2017 the Author(s). Published by PNAS.

  16. Long-term exposure and safety of lacosamide monotherapy for the treatment of partial-onset (focal) seizures: Results from a multicenter, open-label trial.

    Science.gov (United States)

    Vossler, David G; Wechsler, Robert T; Williams, Paulette; Byrnes, William; Therriault, Sheila

    2016-10-01

    To assess long-term use and safety of lacosamide (LCM) ≤800 mg/day monotherapy in patients with partial-onset seizures (POS) enrolled previously in a historical-controlled, conversion-to-monotherapy study (SP902; NCT00520741). Patients completing or exiting SP902 with LCM as monotherapy or as adjunctive therapy were eligible to enter this 2-year open-label extension (OLE) trial (SP904; NCT00530855) at a starting dose ±100 mg/day of their final SP902 dose. Investigators could adjust the LCM dose to 100-800 mg/day and add up to two antiepileptic drugs to optimize tolerability and seizure reduction. Three hundred twenty-two patients received LCM: 210 patients (65.2%) completed and 112 (34.8%) discontinued, most commonly owing to withdrawal of consent (9.3%). Two hundred fifty-eight patients (80.1%) had ≥1 year of and 216 (67.1%) had ≥2 years of LCM exposure, of whom 179/258 (69.4%) achieved LCM monotherapy lasting for any 12-month period, and 126/216 (58.3%) patients exposed for ≥24 months achieved LCM monotherapy for any 24-month period. Total exposure = 525.5 patient-years. The median modal dose was 500 mg/day. Two hundred ninety-two patients (90.7%) achieved LCM monotherapy at some point during the study. Sixty-five of 87 patients who exited and 193/235 who completed SP902 were exposed for ≥12 months, and 43.1% and 78.2%, respectively, achieved LCM monotherapy for ≥12 months. Median LCM monotherapy duration was 587.0 days (2-791 days); 91.0% of patients reported treatment-emergent adverse events, of which the most common were dizziness (27.3%), headache (17.1%), and nausea (14.3%). Compared with the SP902 study baseline, 74.2% of patients had a ≥50% seizure reduction and 5.6% were seizure-free at 24 months. The majority of patients were receiving LCM monotherapy at 0, 12, and 24 months in this OLE. Lacosamide monotherapy (median dose of 500 mg/day) had a safety profile similar to that of adjunctive therapy studies. These results support the use of

  17. Kinome-wide shRNA Screen Identifies the Receptor Tyrosine Kinase AXL as a Key Regulator for Mesenchymal Glioblastoma Stem-like Cells

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    Peng Cheng

    2015-05-01

    Full Text Available Glioblastoma is a highly lethal cancer for which novel therapeutics are urgently needed. Two distinct subtypes of glioblastoma stem-like cells (GSCs were recently identified: mesenchymal (MES and proneural (PN. To identify mechanisms to target the more aggressive MES GSCs, we combined transcriptomic expression analysis and kinome-wide short hairpin RNA screening of MES and PN GSCs. In comparison to PN GSCs, we found significant upregulation and phosphorylation of the receptor tyrosine kinase AXL in MES GSCs. Knockdown of AXL significantly decreased MES GSC self-renewal capacity in vitro and inhibited the growth of glioblastoma patient-derived xenografts. Moreover, inhibition of AXL with shRNA or pharmacologic inhibitors also increased cell death significantly more in MES GSCs. Clinically, AXL expression was elevated in the MES GBM subtype and significantly correlated with poor prognosis in multiple cancers. In conclusion, we identified AXL as a potential molecular target for novel approaches to treat glioblastoma and other solid cancers.

  18. Admixture mapping of African-American women in the AMBER Consortium identifies new loci for breast cancer and estrogen-receptor subtypes

    Directory of Open Access Journals (Sweden)

    Edward Antonio Ruiz-Narvaez

    2016-09-01

    Full Text Available Recent genetic admixture coupled with striking differences in incidence of estrogen receptor (ER breast cancer subtypes, as well as severity, between women of African and European ancestry, provides an excellent rationale for performing admixture mapping in African American women with breast cancer risk. We performed the largest breast cancer admixture mapping study with in African American women to identify novel genomic regions associated with the disease. We conducted a genome-wide admixture scan using 2,624 autosomal ancestry informative markers (AIMs in 3,629 breast cancer cases (including 1,968 ER-positive, 1093 ER-negative and 601 triple-negative and 4,658 controls from the African American Breast Cancer Epidemiology and Risk (AMBER Consortium, a collaborative study of four large geographically different epidemiological studies of breast cancer in African American women. We used an independent case-control study to test for SNP association in regions with genome-wide significant admixture signals. We found two novel genome-wide significant regions of excess African ancestry, 4p16.1 and 17q25.1, associated with ER-positive breast cancer. Two regions known to harbor breast cancer variants, 10q26 and 11q13, were also identified with excess of African ancestry. Fine-mapping of the identified genome-wide significant regions suggests the presence of significant genetic associations with ER-positive breast cancer in 4p16.1 and 11q13. In summary, we identified three novel genomic regions associated with breast cancer risk by ER status, suggesting that additional previously unidentified variants may contribute to the racial differences in breast cancer risk in the African American population.

  19. A deep learning based strategy for identifying and associating mitotic activity with gene expression derived risk categories in estrogen receptor positive breast cancers.

    Science.gov (United States)

    Romo-Bucheli, David; Janowczyk, Andrew; Gilmore, Hannah; Romero, Eduardo; Madabhushi, Anant

    2017-06-01

    The treatment and management of early stage estrogen receptor positive (ER+) breast cancer is hindered by the difficulty in identifying patients who require adjuvant chemotherapy in contrast to those that will respond to hormonal therapy. To distinguish between the more and less aggressive breast tumors, which is a fundamental criterion for the selection of an appropriate treatment plan, Oncotype DX (ODX) and other gene expression tests are typically employed. While informative, these gene expression tests are expensive, tissue destructive, and require specialized facilities. Bloom-Richardson (BR) grade, the common scheme employed in breast cancer grading, has been shown to be correlated with the Oncotype DX risk score. Unfortunately, studies have also shown that the BR grade determined experiences notable inter-observer variability. One of the constituent categories in BR grading is the mitotic index. The goal of this study was to develop a deep learning (DL) classifier to identify mitotic figures from whole slides images of ER+ breast cancer, the hypothesis being that the number of mitoses identified by the DL classifier would correlate with the corresponding Oncotype DX risk categories. The mitosis detector yielded an average F-score of 0.556 in the AMIDA mitosis dataset using a 6-fold validation setup. For a cohort of 174 whole slide images with early stage ER+ breast cancer for which the corresponding Oncotype DX score was available, the distributions of the number of mitoses identified by the DL classifier was found to be significantly different between the high vs low Oncotype DX risk groups (P machine classifier trained to separate low/high Oncotype DX risk categories using the mitotic count determined by the DL classifier yielded a 83.19% classification accuracy. © 2017 International Society for Advancement of Cytometry. © 2017 International Society for Advancement of Cytometry.

  20. Genome-wide association studies in women of African ancestry identified 3q26.21 as a novel susceptibility locus for oestrogen receptor negative breast cancer.

    Science.gov (United States)

    Huo, Dezheng; Feng, Ye; Haddad, Stephen; Zheng, Yonglan; Yao, Song; Han, Yoo-Jeong; Ogundiran, Temidayo O; Adebamowo, Clement; Ojengbede, Oladosu; Falusi, Adeyinka G; Zheng, Wei; Blot, William; Cai, Qiuyin; Signorello, Lisa; John, Esther M; Bernstein, Leslie; Hu, Jennifer J; Ziegler, Regina G; Nyante, Sarah; Bandera, Elisa V; Ingles, Sue A; Press, Michael F; Deming, Sandra L; Rodriguez-Gil, Jorge L; Nathanson, Katherine L; Domchek, Susan M; Rebbeck, Timothy R; Ruiz-Narváez, Edward A; Sucheston-Campbell, Lara E; Bensen, Jeannette T; Simon, Michael S; Hennis, Anselm; Nemesure, Barbara; Leske, M Cristina; Ambs, Stefan; Chen, Lin S; Qian, Frank; Gamazon, Eric R; Lunetta, Kathryn L; Cox, Nancy J; Chanock, Stephen J; Kolonel, Laurence N; Olshan, Andrew F; Ambrosone, Christine B; Olopade, Olufunmilayo I; Palmer, Julie R; Haiman, Christopher A

    2016-11-01

    Multiple breast cancer loci have been identified in previous genome-wide association studies, but they were mainly conducted in populations of European ancestry. Women of African ancestry are more likely to have young-onset and oestrogen receptor (ER) negative breast cancer for reasons that are unknown and understudied. To identify genetic risk factors for breast cancer in women of African descent, we conducted a meta-analysis of two genome-wide association studies of breast cancer; one study consists of 1,657 cases and 2,029 controls genotyped with Illumina’s HumanOmni2.5 BeadChip and the other study included 3,016 cases and 2,745 controls genotyped using Illumina Human1M-Duo BeadChip. The top 18,376 single nucleotide polymorphisms (SNP) from the meta-analysis were replicated in the third study that consists of 1,984 African Americans cases and 2,939 controls. We found that SNP rs13074711, 26.5 Kb upstream of TNFSF10 at 3q26.21, was significantly associated with risk of oestrogen receptor (ER)-negative breast cancer (odds ratio [OR]=1.29, 95% CI: 1.18-1.40; P = 1.8 × 10 − 8). Functional annotations suggest that the TNFSF10 gene may be involved in breast cancer aetiology, but further functional experiments are needed. In addition, we confirmed SNP rs10069690 was the best indicator for ER-negative breast cancer at 5p15.33 (OR = 1.30; P = 2.4 × 10 − 10) and identified rs12998806 as the best indicator for ER-positive breast cancer at 2q35 (OR = 1.34; P = 2.2 × 10 − 8) for women of African ancestry. These findings demonstrated additional susceptibility alleles for breast cancer can be revealed in diverse populations and have important public health implications in building race/ethnicity-specific risk prediction model for breast cancer.

  1. Association analysis of bitter receptor genes in five isolated populations identifies a significant correlation between TAS2R43 variants and coffee liking.

    Science.gov (United States)

    Pirastu, Nicola; Kooyman, Maarten; Traglia, Michela; Robino, Antonietta; Willems, Sara M; Pistis, Giorgio; d'Adamo, Pio; Amin, Najaf; d'Eustacchio, Angela; Navarini, Luciano; Sala, Cinzia; Karssen, Lennart C; van Duijn, Cornelia; Toniolo, Daniela; Gasparini, Paolo

    2014-01-01

    Coffee, one of the most popular beverages in the world, contains many different physiologically active compounds with a potential impact on people's health. Despite the recent attention given to the genetic basis of its consumption, very little has been done in understanding genes influencing coffee preference among different individuals. Given its markedly bitter taste, we decided to verify if bitter receptor genes (TAS2Rs) variants affect coffee liking. In this light, 4066 people from different parts of Europe and Central Asia filled in a field questionnaire on coffee liking. They have been consequently recruited and included in the study. Eighty-eight SNPs covering the 25 TAS2R genes were selected from the available imputed ones and used to run association analysis for coffee liking. A significant association was detected with three SNP: one synonymous and two functional variants (W35S and H212R) on the TAS2R43 gene. Both variants have been shown to greatly reduce in vitro protein activity. Surprisingly the wild type allele, which corresponds to the functional form of the protein, is associated to higher liking of coffee. Since the hTAS2R43 receptor is sensible to caffeine, we verified if the detected variants produced differences in caffeine bitter perception on a subsample of people coming from the FVG cohort. We found a significant association between differences in caffeine perception and the H212R variant but not with the W35S, which suggests that the effect of the TAS2R43 gene on coffee liking is mediated by caffeine and in particular by the H212R variant. No other significant association was found with other TAS2R genes. In conclusion, the present study opens new perspectives in the understanding of coffee liking. Further studies are needed to clarify the role of the TAS2R43 gene in coffee hedonics and to identify which other genes and pathways are involved in its genetics.

  2. Association analysis of bitter receptor genes in five isolated populations identifies a significant correlation between TAS2R43 variants and coffee liking.

    Directory of Open Access Journals (Sweden)

    Nicola Pirastu

    Full Text Available Coffee, one of the most popular beverages in the world, contains many different physiologically active compounds with a potential impact on people's health. Despite the recent attention given to the genetic basis of its consumption, very little has been done in understanding genes influencing coffee preference among different individuals. Given its markedly bitter taste, we decided to verify if bitter receptor genes (TAS2Rs variants affect coffee liking. In this light, 4066 people from different parts of Europe and Central Asia filled in a field questionnaire on coffee liking. They have been consequently recruited and included in the study. Eighty-eight SNPs covering the 25 TAS2R genes were selected from the available imputed ones and used to run association analysis for coffee liking. A significant association was detected with three SNP: one synonymous and two functional variants (W35S and H212R on the TAS2R43 gene. Both variants have been shown to greatly reduce in vitro protein activity. Surprisingly the wild type allele, which corresponds to the functional form of the protein, is associated to higher liking of coffee. Since the hTAS2R43 receptor is sensible to caffeine, we verified if the detected variants produced differences in caffeine bitter perception on a subsample of people coming from the FVG cohort. We found a significant association between differences in caffeine perception and the H212R variant but not with the W35S, which suggests that the effect of the TAS2R43 gene on coffee liking is mediated by caffeine and in particular by the H212R variant. No other significant association was found with other TAS2R genes. In conclusion, the present study opens new perspectives in the understanding of coffee liking. Further studies are needed to clarify the role of the TAS2R43 gene in coffee hedonics and to identify which other genes and pathways are involved in its genetics.

  3. Development and Implementation of a High-Throughput High-Content Screening Assay to Identify Inhibitors of Androgen Receptor Nuclear Localization in Castration-Resistant Prostate Cancer Cells

    Science.gov (United States)

    Nguyen, Minh M.; Dar, Javid A.; Ai, Junkui; Wang, Yujuan; Masoodi, Khalid Z.; Shun, Tongying; Shinde, Sunita; Camarco, Daniel P.; Hua, Yun; Huryn, Donna M.; Wilson, Gabriela Mustata; Lazo, John S.; Nelson, Joel B.; Wipf, Peter

    2016-01-01

    Abstract Patients with castration-resistant prostate cancer (CRPC) can be treated with abiraterone, a potent inhibitor of androgen synthesis, or enzalutamide, a second-generation androgen receptor (AR) antagonist, both targeting AR signaling. However, most patients relapse after several months of therapy and a majority of patients with relapsed CRPC tumors express the AR target gene prostate-specific antigen (PSA), suggesting that AR signaling is reactivated and can be targeted again to inhibit the relapsed tumors. Novel small molecules capable of inhibiting AR function may lead to urgently needed therapies for patients resistant to abiraterone, enzalutamide, and/or other previously approved antiandrogen therapies. Here, we describe a high-throughput high-content screening (HCS) campaign to identify small-molecule inhibitors of AR nuclear localization in the C4-2 CRPC cell line stably transfected with GFP-AR-GFP (2GFP-AR). The implementation of this HCS assay to screen a National Institutes of Health library of 219,055 compounds led to the discovery of 3 small molecules capable of inhibiting AR nuclear localization and function in C4-2 cells, demonstrating the feasibility of using this cell-based phenotypic assay to identify small molecules targeting the subcellular localization of AR. Furthermore, the three hit compounds provide opportunities to develop novel AR drugs with potential for therapeutic intervention in CRPC patients who have relapsed after treatment with antiandrogens, such as abiraterone and/or enzalutamide. PMID:27187604

  4. A human D1 dopamine receptor gene is located on chromosome 5 at q35.1 and identifies an EcoRI RFLP.

    OpenAIRE

    Grandy, D K; Zhou, Q Y; Allen, L; Litt, R; Magenis, R E; Civelli, O; Litt, M

    1990-01-01

    Dopaminergic neurons have been shown to affect voluntary movement, hormone secretion, and emotional tone. Mediating these activities are two receptor subtypes, D1 and D2, which are biochemically and pharmacologically distinct. The D1 subtype, the most abundant form of dopamine receptor in the central nervous system, stimulates adenylate cyclase, modulates D2 receptor activity, regulates neuron growth and differentiation, and mediates several behavioral responses. Recently we reported the clon...

  5. A Genetic Screen Identifies a Requirement for Cysteine-Rich-Receptor-Like Kinases in Rice NH1 (OsNPR1-Mediated Immunity.

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    Mawsheng Chern

    2016-05-01

    Full Text Available Systemic acquired resistance, mediated by the Arabidopsis NPR1 gene and the rice NH1 gene, confers broad-spectrum immunity to diverse pathogens. NPR1 and NH1 interact with TGA transcription factors to activate downstream defense genes. Despite the importance of this defense response, the signaling components downstream of NPR1/NH1 and TGA proteins are poorly defined. Here we report the identification of a rice mutant, snim1, which suppresses NH1-mediated immunity and demonstrate that two genes encoding previously uncharacterized cysteine-rich-receptor-like kinases (CRK6 and CRK10, complement the snim1 mutant phenotype. Silencing of CRK6 and CRK10 genes individually in the parental genetic background recreates the snim1 phenotype. We identified a rice mutant in the Kitaake genetic background with a frameshift mutation in crk10; this mutant also displays a compromised immune response highlighting the important role of crk10. We also show that elevated levels of NH1 expression lead to enhanced CRK10 expression and that the rice TGA2.1 protein binds to the CRK10 promoter. These experiments demonstrate a requirement for CRKs in NH1-mediated immunity and establish a molecular link between NH1 and induction of CRK10 expression.

  6. Tandem mass spectrometry, but not T-cell receptor excision circle analysis, identifies newborns with late-onset adenosine deaminase deficiency.

    Science.gov (United States)

    la Marca, Giancarlo; Canessa, Clementina; Giocaliere, Elisa; Romano, Francesca; Duse, Marzia; Malvagia, Sabrina; Lippi, Francesca; Funghini, Silvia; Bianchi, Leila; Della Bona, Maria Luisa; Valleriani, Claudia; Ombrone, Daniela; Moriondo, Maria; Villanelli, Fabio; Speckmann, Carsten; Adams, Stuart; Gaspar, Bobby H; Hershfield, Michael; Santisteban, Ines; Fairbanks, Lynette; Ragusa, Giovanni; Resti, Massimo; de Martino, Maurizio; Guerrini, Renzo; Azzari, Chiara

    2013-06-01

    Adenosine deaminase (ADA)-severe combined immunodeficiency (SCID) is caused by genetic variants that disrupt the function of ADA. In its early-onset form, it is rapidly fatal to infants. Delayed or late-onset ADA-SCID is characterized by insidious progressive immunodeficiency that leads to permanent organ damage or death. Quantification of T-cell receptor excision circles (TRECs) or tandem mass spectrometry (tandem-MS) analysis of dried blood spots (DBSs) collected at birth can identify newborns with early-onset ADA-SCID and are used in screening programs. However, it is not clear whether these analyses can identify newborns who will have delayed or late-onset ADA-SCID before symptoms appear. We performed a retrospective study to evaluate whether tandem-MS and quantitative TREC analyses of DBSs could identify newborns who had delayed-onset ADA-SCID later in life. We tested stored DBSs collected at birth from 3 patients with delayed-onset ADA-SCID using tandem-MS (PCT EP2010/070517) to evaluate levels of adenosine and 2'-deoxyadenosine and real-time PCR to quantify TREC levels. We also analyzed DBSs from 3 newborns with early-onset ADA-SCID and 2 healthy newborn carriers of ADA deficiency. The DBSs taken at birth from the 3 patients with delayed-onset ADA-SCID had adenosine levels of 10, 25, and 19 μmol/L (normal value, <1.5 μmol/L) and 2'-deoxyadenosine levels of 0.7, 2.7, and 2.4 μmol/L (normal value, <0.07 μmol/L); the mean levels of adenosine and 2'-deoxyadenosine were respectively 12.0- and 27.6-fold higher than normal values. DBSs taken at birth from all 3 patients with delayed-onset ADA deficiency had normal TREC levels, but TRECs were undetectable in blood samples taken from the same patients at the time of diagnosis. Tandem-MS but not TREC quantification identifies newborns with delayed- or late-onset ADA deficiency. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  7. Integrated ligand-receptor bioinformatic and in vitro functional analysis identifies active TGFA/EGFR signaling loop in papillary thyroid carcinomas.

    Directory of Open Access Journals (Sweden)

    Debora Degl'Innocenti

    Full Text Available BACKGROUND: Papillary thyroid carcinoma (PTCs, the most frequent thyroid cancer, is usually not life threatening, but may recur or progress to aggressive forms resistant to conventional therapies. A more detailed understanding of the signaling pathways activated in PTCs may help to identify novel therapeutic approaches against these tumors. The aim of this study is to identify signaling pathways activated in PTCs. METHODOLOGY/PRINCIPAL FINDINGS: We examined coordinated gene expression patterns of ligand/receptor (L/R pairs using the L/R database DRLP-rev1 and five publicly available thyroid cancer datasets of gene expression on a total of 41 paired PTC/normal thyroid tissues. We identified 26 (up and 13 (down L/R pairs coordinately and differentially expressed. The relevance of these L/R pairs was confirmed by performing the same analysis on REarranged during Transfection (RET/PTC1-infected thyrocytes with respect to normal thyrocytes. TGFA/EGFR emerged as one of the most tightly regulated L/R pair. Furthermore, PTC clinical samples analyzed by real-time RT-PCR expressed EGFR transcript levels similar to those of 5 normal thyroid tissues from patients with pathologies other than thyroid cancer, whereas significantly elevated levels of TGFA transcripts were only present in PTCs. Biochemical analysis of PTC cell lines demonstrated the presence of EGFR on the cell membrane and TGFA in conditioned media. Moreover, conditioned medium of the PTC cell line NIM-1 activated EGFR expressed on HeLa cells, culminating in both ERK and AKT phosphorylation. In NIM-1 cells harboring BRAF mutation, TGFA stimulated proliferation, contributing to PI3K/AKT activation independent of MEK/ERK signaling. CONCLUSIONS/SIGNIFICANCE: We compiled a reliable list of L/R pairs associated with PTC and validated the biological role of one of the emerged L/R pair, the TGFA/EGFR, in this cancer, in vitro. These data provide a better understanding of the factors involved in the

  8. Failure of anti-T-cell receptor V beta antibodies to consistently identify a malignant T-cell clone in Sézary syndrome.

    Science.gov (United States)

    Bigler, R D; Boselli, C M; Foley, B; Vonderheid, E C

    1996-11-01

    Monoclonal antibodies (MAbs) reacting with the human T cell receptor (TCR) V beta or V alpha region have been shown to be almost as specific as a private idiotypic MAb in identifying T cell clones. When available, V beta-specific MAbs offer the ease of immunofluorescence analysis to identify and quantitate expanded malignant or nonmalignant T cell populations without requiring polymerase chain reaction (PCR) technology to evaluate expression of V beta gene families. The V beta expression of peripheral blood lymphocytes from twenty-three consecutive patients with Sézary syndrome has been analyzed by reverse transcriptase (RT)-PCR. Ten patients had malignant T cell clones that expressed a TCR V beta corresponding to a commercially available anti-V beta antibody. Immunofluorescence staining with anti-V beta MAbs showed a direct correlation with RT-PCR results in seven of ten patients. No false positive reactivity was noted on immunofluorescence staining with any MAb. Cells from three patients, however, did not react with the corresponding anti-V beta MAb. These three cases expressed a TCR V beta from gene families containing a single member, ie, V beta 14, V beta 18, and V beta 20, yet MAbs reported to be specific for these regions failed to react with the T cell clone from these patients. Sequencing of the PCR product in these cases confirmed the RT-PCR results. Cells from two patients expressed a TCR using V beta 5.1-D beta 1.1 genes with different J-C segments. One patient's cells reacted with an anti-V beta 5.1 MAb (LC4) whereas the other patient's cells bound one-tenth the amount of this same MAb. These results indicate that currently available anti-TCR V region MAbs may not react consistently with T cell clones expressing the corresponding V region or may react with a low affinity making detection difficult. Differences in the J-C junction or in CDR3 may influence the binding of these MAbs. Until the false negative rate is reduced and the fine specificity and

  9. Fourier transform coupled tryptophan scanning mutagenesis identifies a bending point on the lipid-exposed δM3 transmembrane domain of the Torpedo californica nicotinic acetylcholine receptor

    Science.gov (United States)

    Caballero-Rivera, Daniel; Cruz-Nieves, Omar A; Oyola-Cintrón, Jessica; Torres-Núñez, David A; Otero-Cruz, José D

    2011-01-01

    The nicotinic acetylcholine receptor (nAChR) is a member of a family of ligand-gated ion channels that mediate diverse physiological functions, including fast synaptic transmission along the peripheral and central nervous systems. Several studies have made significant advances toward determining the structure and dynamics of the lipid-exposed domains of the nAChR. However, a high-resolution atomic structure of the nAChR still remains elusive. In this study, we extended the Fourier transform coupled tryptophan scanning mutagenesis (FT-TrpScanM) approach to gain insight into the secondary structure of the δM3 transmembrane domain of the Torpedo californica nAChR, to monitor conformational changes experienced by this domain during channel gating, and to identify which lipid-exposed positions are linked to the regulation of ion channel kinetics. The perturbations produced by periodic tryptophan substitutions along the δM3 transmembrane domain were characterized by two-electrode voltage clamp and 125I-labeled α-bungarotoxin binding assays. The periodicity profiles and Fourier transform spectra of this domain revealed similar helical structures for the closed- and open-channel states. However, changes in the oscillation patterns observed between positions Val-299 and Val-304 during transition between the closed- and open-channel states can be explained by the structural effects caused by the presence of a bending point introduced by a Thr-Gly motif at positions 300–301. The changes in periodicity and localization of residues between the closed-and open-channel states could indicate a structural transition between helix types in this segment of the domain. Overall, the data further demonstrate a functional link between the lipid-exposed transmembrane domain and the nAChR gating machinery. PMID:21785268

  10. Elevated urinary levels of urokinase-type plasminogen activator receptor (uPAR) in pancreatic ductal adenocarcinoma identify a clinically high-risk group

    International Nuclear Information System (INIS)

    Sorio, Claudio; Scarpa, Aldo; Mafficini, Andrea; Furlan, Federico; Barbi, Stefano; Bonora, Antonio; Brocco, Giorgio; Blasi, Francesco; Talamini, Giorgio; Bassi, Claudio

    2011-01-01

    The urokinase plasminogen activator receptor is highly expressed and its gene is amplified in about 50% of pancreatic ductal adenocarcinomas; this last feature is associated with worse prognosis. It is unknown whether the level of its soluble form (suPAR) in urine may be a diagnostic-prognostic marker in these patients. The urinary level of suPAR was measured in 146 patients, 94 pancreatic ductal adenocarcinoma and 52 chronic pancreatitis. Urine from 104 healthy subjects with similar age and gender distribution served as controls. suPAR levels were normalized with creatinine levels (suPAR/creatinine, ng/mg) to remove urine dilution effect. Urinary suPAR/creatinine values of pancreatic ductal adenocarcinoma patients were significantly higher (median 9.8; 25 th -75 th percentiles 5.3-20.7) than those of either healthy donors (median 0; 0-0.5) or chronic pancreatitis patients (median 2.7; 0.9-4.7). The distribution of values among cancer patients was widespread and asymmetric, 53% subjects having values beyond the 95 th percentile of healthy donors. The values of suPAR/creatinine did not correlate with tumour stage, Ca19-9 or CEA levels. Higher values correlated with poor prognosis among non-resected patients at univariate analysis; multivariate Cox regression identified high urinary suPAR/creatinine as an independent predictor of poor survival among all cancer patients (odds ratio 2.10, p = 0.0023), together with tumour stage (stage III odds ratio 2.65, p = 0.0017; stage IV odds ratio 4.61, p < 0.0001) and female gender (odds ratio 1.85, p = 0.01). A high urinary suPAR/creatinine ratio represents a useful marker for the identification of a subset of patients with poorer outcome

  11. Integrative analysis of deep sequencing data identifies estrogen receptor early response genes and links ATAD3B to poor survival in breast cancer.

    Directory of Open Access Journals (Sweden)

    Kristian Ovaska

    Full Text Available Identification of responsive genes to an extra-cellular cue enables characterization of pathophysiologically crucial biological processes. Deep sequencing technologies provide a powerful means to identify responsive genes, which creates a need for computational methods able to analyze dynamic and multi-level deep sequencing data. To answer this need we introduce here a data-driven algorithm, SPINLONG, which is designed to search for genes that match the user-defined hypotheses or models. SPINLONG is applicable to various experimental setups measuring several molecular markers in parallel. To demonstrate the SPINLONG approach, we analyzed ChIP-seq data reporting PolII, estrogen receptor α (ERα, H3K4me3 and H2A.Z occupancy at five time points in the MCF-7 breast cancer cell line after estradiol stimulus. We obtained 777 ERa early responsive genes and compared the biological functions of the genes having ERα binding within 20 kb of the transcription start site (TSS to genes without such binding site. Our results show that the non-genomic action of ERα via the MAPK pathway, instead of direct ERa binding, may be responsible for early cell responses to ERα activation. Our results also indicate that the ERα responsive genes triggered by the genomic pathway are transcribed faster than those without ERα binding sites. The survival analysis of the 777 ERα responsive genes with 150 primary breast cancer tumors and in two independent validation cohorts indicated the ATAD3B gene, which does not have ERα binding site within 20 kb of its TSS, to be significantly associated with poor patient survival.

  12. Immunoprofiling of human uterine mast cells identifies three phenotypes and expression of ERβ and glucocorticoid receptor [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Bianca De Leo

    2017-05-01

    Full Text Available Background: Human mast cells (MCs are long-lived tissue-resident immune cells characterised by granules containing the proteases chymase and/or tryptase. Their phenotype is modulated by their tissue microenvironment. The human uterus has an outer muscular layer (the myometrium surrounding the endometrium, both of which play an important role in supporting a pregnancy. The endometrium is a sex steroid target tissue consisting of epithelial cells (luminal, glandular surrounded by a multicellular stroma, with the latter containing an extensive vascular compartment as well as fluctuating populations of immune cells that play an important role in regulating tissue function. The role of MCs in the human uterus is poorly understood with little known about their regulation or the impact of steroids on their differentiation status. The current study had two aims: 1 To investigate the spatial and temporal location of uterine MCs and determine their phenotype; 2 To determine whether MCs express receptors for steroids implicated in uterine function, including oestrogen (ERα, ERβ, progesterone (PR and glucocorticoids (GR. Methods: Tissue samples from women (n=46 were used for RNA extraction or fixed for immunohistochemistry. Results: Messenger RNAs encoded by TPSAB1 (tryptase and CMA1 (chymase were detected in endometrial tissue homogenates. Immunohistochemistry revealed the relative abundance of tryptase MCs was myometrium>basal endometrium>functional endometrium. We show for the first time that uterine MCs are predominantly of the classical MC subtypes: (positive, +; negative, - tryptase+/chymase- and tryptase+/chymase+, but a third subtype was also identified (tryptase-/chymase+. Tryptase+ MCs were of an ERβ+/ERα-/PR-/GR+ phenotype mirroring other uterine immune cell populations, including natural killer cells. Conclusions: Endometrial tissue resident immune MCs have three protease-specific phenotypes. Expression of both ERβ and GR in MCs mirrors

  13. Circulating LH/hCG receptor (LHCGR may identify pre-treatment IVF patients at risk of OHSS and poor implantation

    Directory of Open Access Journals (Sweden)

    Chambers Anne E

    2011-12-01

    Full Text Available Abstract Background Successful pregnancy via in vitro fertilization (IVF depends on the recovery of an adequate number of healthy oocytes and on blastocyst implantation following uterine transfer. Two hormones, LH and hCG, utilize a common LH/hCG receptor (LHCGR, variations in which have profound implications in human reproduction. Soluble LHCGR (sLHCGR is released from experimental cell lines and placental explants and it can be detected in the follicular fluid and serum. Methods To evaluate the impact of circulating soluble LHCGR (sLHCGR in fertility treatment, we measured sLHCGR and LH-sLHCGR complex in serum from women seeking IVF using specifically developed quantitative enzyme-linked immunosorbent assays (ELISA. Following an IVF cycle of treatment, patients were grouped according to oocyte yield into low (lower than or equal to 7 oocytes, intermediate (8-14 oocytes and high (greater than or equal to 15 oocytes responders and pregnancy outcome noted. Results Pre-treatment sLHCGR identified many women at risk of ovarian hyperstimulation. Low levels of sLHCGR were associated with pregnancy in both high and low responders but sLHCGR did not significantly affect the treatment outcome of intermediate responders. Low responders who failed to become pregnant had high levels of circulating sLHCGR bound to LH (LH-sLHCGR. Conclusions Pre-treatment measurement of sLHCGR could be used to tailor individual fertility treatment programs and improve outcomes by avoiding ovarian hyperstimulation and poor embryo implantation.

  14. Functional genomics analysis of big data identifies novel peroxisome proliferator–activated receptor gamma target single nucleotide polymorphisms showing association with cardiometabolic outcomes

    Science.gov (United States)

    Background Cardiovascular disease and type 2 diabetes mellitus represent overlapping diseases where a large portion of the variation attributable to genetics remains unexplained. An important player in their pathogenesis is peroxisome proliferator–activated receptor gamma (PPARgamma) that is involve...

  15. Mutation analysis of peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) and relationships of identified amino acid polymorphisms to Type II diabetes mellitus

    DEFF Research Database (Denmark)

    Ek, J; Andersen, G; Urhammer, S A

    2001-01-01

    This study aimed to investigate if variability in the peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) gene is associated with Type II (non-insulin-dependent) diabetes mellitus.......This study aimed to investigate if variability in the peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) gene is associated with Type II (non-insulin-dependent) diabetes mellitus....

  16. Genome-Wide Gene-Environment Study Identifies Glutamate Receptor Gene GRIN2A as a Parkinson's Disease Modifier Gene via Interaction with Coffee

    Science.gov (United States)

    Hamza, Taye H.; Chen, Honglei; Hill-Burns, Erin M.; Rhodes, Shannon L.; Montimurro, Jennifer; Kay, Denise M.; Tenesa, Albert; Kusel, Victoria I.; Sheehan, Patricia; Eaaswarkhanth, Muthukrishnan; Yearout, Dora; Samii, Ali; Roberts, John W.; Agarwal, Pinky; Bordelon, Yvette; Park, Yikyung; Wang, Liyong; Gao, Jianjun; Vance, Jeffery M.; Kendler, Kenneth S.; Bacanu, Silviu-Alin; Scott, William K.; Ritz, Beate; Nutt, John; Factor, Stewart A.; Zabetian, Cyrus P.; Payami, Haydeh

    2011-01-01

    Our aim was to identify genes that influence the inverse association of coffee with the risk of developing Parkinson's disease (PD). We used genome-wide genotype data and lifetime caffeinated-coffee-consumption data on 1,458 persons with PD and 931 without PD from the NeuroGenetics Research Consortium (NGRC), and we performed a genome-wide association and interaction study (GWAIS), testing each SNP's main-effect plus its interaction with coffee, adjusting for sex, age, and two principal components. We then stratified subjects as heavy or light coffee-drinkers and performed genome-wide association study (GWAS) in each group. We replicated the most significant SNP. Finally, we imputed the NGRC dataset, increasing genomic coverage to examine the region of interest in detail. The primary analyses (GWAIS, GWAS, Replication) were performed using genotyped data. In GWAIS, the most significant signal came from rs4998386 and the neighboring SNPs in GRIN2A. GRIN2A encodes an NMDA-glutamate-receptor subunit and regulates excitatory neurotransmission in the brain. Achieving P2df = 10−6, GRIN2A surpassed all known PD susceptibility genes in significance in the GWAIS. In stratified GWAS, the GRIN2A signal was present in heavy coffee-drinkers (OR = 0.43; P = 6×10−7) but not in light coffee-drinkers. The a priori Replication hypothesis that “Among heavy coffee-drinkers, rs4998386_T carriers have lower PD risk than rs4998386_CC carriers” was confirmed: ORReplication = 0.59, PReplication = 10−3; ORPooled = 0.51, PPooled = 7×10−8. Compared to light coffee-drinkers with rs4998386_CC genotype, heavy coffee-drinkers with rs4998386_CC genotype had 18% lower risk (P = 3×10−3), whereas heavy coffee-drinkers with rs4998386_TC genotype had 59% lower risk (P = 6×10−13). Imputation revealed a block of SNPs that achieved P2dfcoffee-drinkers. This study is proof of concept that inclusion of environmental factors can help identify genes that

  17. Genome-wide gene-environment study identifies glutamate receptor gene GRIN2A as a Parkinson's disease modifier gene via interaction with coffee.

    Science.gov (United States)

    Hamza, Taye H; Chen, Honglei; Hill-Burns, Erin M; Rhodes, Shannon L; Montimurro, Jennifer; Kay, Denise M; Tenesa, Albert; Kusel, Victoria I; Sheehan, Patricia; Eaaswarkhanth, Muthukrishnan; Yearout, Dora; Samii, Ali; Roberts, John W; Agarwal, Pinky; Bordelon, Yvette; Park, Yikyung; Wang, Liyong; Gao, Jianjun; Vance, Jeffery M; Kendler, Kenneth S; Bacanu, Silviu-Alin; Scott, William K; Ritz, Beate; Nutt, John; Factor, Stewart A; Zabetian, Cyrus P; Payami, Haydeh

    2011-08-01

    Our aim was to identify genes that influence the inverse association of coffee with the risk of developing Parkinson's disease (PD). We used genome-wide genotype data and lifetime caffeinated-coffee-consumption data on 1,458 persons with PD and 931 without PD from the NeuroGenetics Research Consortium (NGRC), and we performed a genome-wide association and interaction study (GWAIS), testing each SNP's main-effect plus its interaction with coffee, adjusting for sex, age, and two principal components. We then stratified subjects as heavy or light coffee-drinkers and performed genome-wide association study (GWAS) in each group. We replicated the most significant SNP. Finally, we imputed the NGRC dataset, increasing genomic coverage to examine the region of interest in detail. The primary analyses (GWAIS, GWAS, Replication) were performed using genotyped data. In GWAIS, the most significant signal came from rs4998386 and the neighboring SNPs in GRIN2A. GRIN2A encodes an NMDA-glutamate-receptor subunit and regulates excitatory neurotransmission in the brain. Achieving P(2df) = 10(-6), GRIN2A surpassed all known PD susceptibility genes in significance in the GWAIS. In stratified GWAS, the GRIN2A signal was present in heavy coffee-drinkers (OR = 0.43; P = 6×10(-7)) but not in light coffee-drinkers. The a priori Replication hypothesis that "Among heavy coffee-drinkers, rs4998386_T carriers have lower PD risk than rs4998386_CC carriers" was confirmed: OR(Replication) = 0.59, P(Replication) = 10(-3); OR(Pooled) = 0.51, P(Pooled) = 7×10(-8). Compared to light coffee-drinkers with rs4998386_CC genotype, heavy coffee-drinkers with rs4998386_CC genotype had 18% lower risk (P = 3×10(-3)), whereas heavy coffee-drinkers with rs4998386_TC genotype had 59% lower risk (P = 6×10(-13)). Imputation revealed a block of SNPs that achieved P(2df)coffee-drinkers. This study is proof of concept that inclusion of environmental factors can help identify

  18. Genome-wide gene-environment study identifies glutamate receptor gene GRIN2A as a Parkinson's disease modifier gene via interaction with coffee.

    Directory of Open Access Journals (Sweden)

    Taye H Hamza

    2011-08-01

    Full Text Available Our aim was to identify genes that influence the inverse association of coffee with the risk of developing Parkinson's disease (PD. We used genome-wide genotype data and lifetime caffeinated-coffee-consumption data on 1,458 persons with PD and 931 without PD from the NeuroGenetics Research Consortium (NGRC, and we performed a genome-wide association and interaction study (GWAIS, testing each SNP's main-effect plus its interaction with coffee, adjusting for sex, age, and two principal components. We then stratified subjects as heavy or light coffee-drinkers and performed genome-wide association study (GWAS in each group. We replicated the most significant SNP. Finally, we imputed the NGRC dataset, increasing genomic coverage to examine the region of interest in detail. The primary analyses (GWAIS, GWAS, Replication were performed using genotyped data. In GWAIS, the most significant signal came from rs4998386 and the neighboring SNPs in GRIN2A. GRIN2A encodes an NMDA-glutamate-receptor subunit and regulates excitatory neurotransmission in the brain. Achieving P(2df = 10(-6, GRIN2A surpassed all known PD susceptibility genes in significance in the GWAIS. In stratified GWAS, the GRIN2A signal was present in heavy coffee-drinkers (OR = 0.43; P = 6×10(-7 but not in light coffee-drinkers. The a priori Replication hypothesis that "Among heavy coffee-drinkers, rs4998386_T carriers have lower PD risk than rs4998386_CC carriers" was confirmed: OR(Replication = 0.59, P(Replication = 10(-3; OR(Pooled = 0.51, P(Pooled = 7×10(-8. Compared to light coffee-drinkers with rs4998386_CC genotype, heavy coffee-drinkers with rs4998386_CC genotype had 18% lower risk (P = 3×10(-3, whereas heavy coffee-drinkers with rs4998386_TC genotype had 59% lower risk (P = 6×10(-13. Imputation revealed a block of SNPs that achieved P(2df<5×10(-8 in GWAIS, and OR = 0.41, P = 3×10(-8 in heavy coffee-drinkers. This study is proof of

  19. Interaction of chemokine receptor CXCR4 in monomeric and dimeric state with its endogenous ligand CXCL12: coarse-grained simulations identify differences.

    Science.gov (United States)

    Cutolo, Pasquale; Basdevant, Nathalie; Bernadat, Guillaume; Bachelerie, Françoise; Ha-Duong, Tâp

    2017-02-01

    Despite the recent resolutions of the crystal structure of the chemokine receptor CXCR4 in complex with small antagonists or viral chemokine, a description at the molecular level of the interactions between the full-length CXCR4 and its endogenous ligand, the chemokine CXCL12, in relationship with the receptor recognition and activation, is not yet completely elucidated. Moreover, since CXCR4 is able to form dimers, the question of whether the CXCR4-CXCL12 complex has a 1:1 or 2:1 preferential stoichiometry is still an open question. We present here results of coarse-grained protein-protein docking and molecular dynamics simulations of CXCL12 in association with CXCR4 in monomeric and dimeric states. Our proposed models for the 1:1 and 2:1 CXCR4-CXCL12 quaternary structures are consistent with recognition and activation motifs of both partners provided by the available site-directed mutagenesis data. Notably, we observed that in the 2:1 complex, the chemokine N-terminus makes more steady contacts with the receptor residues critical for binding and activation than in the 1:1 structure, suggesting that the 2:1 stoichiometry would favor the receptor signaling activity with respect to the 1:1 association.

  20. Combined receptor antagonist stimulation of the hypothalamic-pituitary-adrenal axis test identifies impaired negative feedback sensitivity to cortisol in obese men.

    Science.gov (United States)

    Mattsson, Cecilia; Reynolds, Rebecca M; Simonyte, Kotryna; Olsson, Tommy; Walker, Brian R

    2009-04-01

    Hypothalamic-pituitary-adrenal (HPA) axis dysregulation may underlie disorders including obesity, depression, cognitive decline, and the metabolic syndrome. Conventional tests of HPA axis negative feedback rely on glucocorticoid receptor (GR) agonists such as dexamethasone but do not test feedback by endogenous cortisol, potentially mediated by both GR and mineralocorticoid receptors (MR). The objective of the study was to use a combination of GR (RU38486, mifepristone) and MR (spironolactone) antagonists to explore the poorly understood activation of the HPA axis that occurs in obesity. This was a double-blind, placebo-controlled, randomized, crossover study. The study was conducted at a clinical research facility. Participants included 15 lean (body mass index 22.0 +/- 1.6 kg/m(2)) and 16 overweight/obese (body mass index 30.1 +/- 3.5 kg/m(2)) men. Subjects attended on four occasions for blood and saliva sampling every 30 min between 1800 and 2200 h. At 1100 and 1600 h before visits, subjects took 200 mg spironolactone, 400 mg RU38486, 200 mg spironolactone + 400 mg RU38486, or placebo orally. Serum cortisol levels after drug or placebo were measured. Cortisol levels did not differ between lean and obese after placebo. Spironolactone and RU38486 alone had modest effects, increasing cortisol by less than 50% in both groups. However, combined spironolactone plus RU38486 elevated cortisol concentrations substantially, more so in lean than obese men [2.9- (0.3) vs. 2.2 (0.3)-fold elevation, P = 0.002]. Combined receptor antagonist stimulation of the HPA axis reveals redundancy of MR and GR in negative feedback in humans. Obese men have impaired responses to combined receptor antagonist stimulation, suggesting impaired negative feedback by endogenous cortisol. Such an approach may be useful to dissect abnormal HPA axis control in neuropsychiatric and other disorders.

  1. Enhancement of B-cell receptor signaling by a point mutation of adaptor protein 3BP2 identified in human inherited disease cherubism.

    Science.gov (United States)

    Ogi, Kazuhiro; Nakashima, Kenji; Chihara, Kazuyasu; Takeuchi, Kenji; Horiguchi, Tomoko; Fujieda, Shigeharu; Sada, Kiyonao

    2011-09-01

    Tyrosine phosphorylation of adaptor protein c-Abl-Src homology 3 (SH3) domain-binding protein-2 (3BP2, also referred to SH3BP2) positively regulates the B-cell antigen receptor (BCR)-mediated signal transduction, leading to the activation of nuclear factor of activated T cells (NFAT). Here we showed the effect of the proline to arginine substitution of 3BP2 in which is the most common mutation in patients with cherubism (P418R) on B-cell receptor signaling. Comparing to the wild type, overexpression of the mutant form of 3BP2 (3BP2-P416R, corresponding to P418R in human protein) enhanced BCR-mediated activation of NFAT. 3BP2-P416R increased the signaling complex formation with Syk, phospholipase C-γ2 (PLC-γ2), and Vav1. In contrast, 3BP2-P416R could not change the association with the negative regulator 14-3-3. Loss of the association mutant that was incapable to associate with 14-3-3 could not mimic BCR-mediated NFAT activation in Syk-deficient cells. Moreover, BCR-mediated phosphorylation of extracellular signal regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) was not affected by P416R mutation. These results showed that P416R mutation of 3BP2 causes the gain of function in B cells by increasing the interaction with specific signaling molecules. © 2011 The Authors. Journal compilation © 2011 by the Molecular Biology Society of Japan/Blackwell Publishing Ltd.

  2. Transcriptomic analysis identifies gene networks regulated by estrogen receptor α (ERα) and ERβ that control distinct effects of different botanical estrogens

    Science.gov (United States)

    Gong, Ping; Madak-Erdogan, Zeynep; Li, Jilong; Cheng, Jianlin; Greenlief, C. Michael; Helferich, William G.; Katzenellenbogen, John A.

    2014-01-01

    The estrogen receptors (ERs) ERα and ERβ mediate the actions of endogenous estrogens as well as those of botanical estrogens (BEs) present in plants. BEs are ingested in the diet and also widely consumed by postmenopausal women as dietary supplements, often as a substitute for the loss of endogenous estrogens at menopause. However, their activities and efficacies, and similarities and differences in gene expression programs with respect to endogenous estrogens such as estradiol (E2) are not fully understood. Because gene expression patterns underlie and control the broad physiological effects of estrogens, we have investigated and compared the gene networks that are regulated by different BEs and by E2. Our aim was to determine if the soy and licorice BEs control similar or different gene expression programs and to compare their gene regulations with that of E2. Gene expression was examined by RNA-Seq in human breast cancer (MCF7) cells treated with control vehicle, BE or E2. These cells contained three different complements of ERs, ERα only, ERα+ERβ, or ERβ only, reflecting the different ratios of these two receptors in different human breast cancers and in different estrogen target cells. Using principal component, hierarchical clustering, and gene ontology and interactome analyses, we found that BEs regulated many of the same genes as did E2. The genes regulated by each BE, however, were somewhat different from one another, with some genes being regulated uniquely by each compound. The overlap with E2 in regulated genes was greatest for the soy isoflavones genistein and S-equol, while the greatest difference from E2 in gene expression pattern was observed for the licorice root BE liquiritigenin. The gene expression pattern of each ligand depended greatly on the cell background of ERs present. Despite similarities in gene expression pattern with E2, the BEs were generally less stimulatory of genes promoting proliferation and were more pro-apoptotic in their

  3. Monoclonal antibody OKB7, which identifies the 14OKd complement receptor type 2 (CR/sub 2/), also identifies a 72Kd secreted fragment of CR/sub 2/ that contains the C3d-binding site

    Energy Technology Data Exchange (ETDEWEB)

    Myones, B.L.; Ross, G.D.

    1986-03-05

    CR/sub 2/ is a 140-145Kd glycoprotein expressed on B lymphocytes which binds both C3d and Epstein-Barr virus (EBV). OKB7, an IgG/sub 2a/ monoclonal antibody to CR/sub 2/, blocks C3d and EBV binding, while HB-5, another monoclonal IgG/sub 2a/ anti-CR/sub 2/, does not. A 72Kd C3d-binding glycoprotein (gp72), isolated from Raji cell media, was previously thought to be CR/sub 2/ because a polyclonal rabbit anti-gp72 inhibited EC3d rosettes. ELISA assay demonstrated that OKB7, but not HB-5, bound to purified gp72 fixed to microtiter wells. Insoluble and soluble gp72 blocked Raji cell uptake of /sup 125/I-labeled OKB7, but not labeled anti-B2 or HB-5. Rabbit anti-gp72 immunoprecipitated bands at 140Kd and 72Kd from /sup 125/I-labelled and solubilized B cell membranes. Culture media from Raji cells grown in the presence /sup 3/H-labeled amino acids was sequentially immunoprecipitated by irrelevant antibody, OKB7, and HB-5. A single 72Kd radiolabeled band was demonstrated only with OKB7, and this was identical to that produced by the immunoprecipitation of /sup 125/I-labeled gp72 with rabbit anti-gp72. Thus, OKB7, which identifies the 140Kd CR/sub 2/ molecule, also identifies a 72Kd shed fragment of CR/sub 2/ isolated from Raji cell media, which contains the C3d-binding site.

  4. Monoclonal antibody OKB7, which identifies the 14OKd complement receptor type 2 (CR2), also identifies a 72Kd secreted fragment of CR2 that contains the C3d-binding site

    International Nuclear Information System (INIS)

    Myones, B.L.; Ross, G.D.

    1986-01-01

    CR 2 is a 140-145Kd glycoprotein expressed on B lymphocytes which binds both C3d and Epstein-Barr virus (EBV). OKB7, an IgG/sub 2a/ monoclonal antibody to CR 2 , blocks C3d and EBV binding, while HB-5, another monoclonal IgG/sub 2a/ anti-CR 2 , does not. A 72Kd C3d-binding glycoprotein (gp72), isolated from Raji cell media, was previously thought to be CR 2 because a polyclonal rabbit anti-gp72 inhibited EC3d rosettes. ELISA assay demonstrated that OKB7, but not HB-5, bound to purified gp72 fixed to microtiter wells. Insoluble and soluble gp72 blocked Raji cell uptake of 125 I-labeled OKB7, but not labeled anti-B2 or HB-5. Rabbit anti-gp72 immunoprecipitated bands at 140Kd and 72Kd from 125 I-labelled and solubilized B cell membranes. Culture media from Raji cells grown in the presence 3 H-labeled amino acids was sequentially immunoprecipitated by irrelevant antibody, OKB7, and HB-5. A single 72Kd radiolabeled band was demonstrated only with OKB7, and this was identical to that produced by the immunoprecipitation of 125 I-labeled gp72 with rabbit anti-gp72. Thus, OKB7, which identifies the 140Kd CR 2 molecule, also identifies a 72Kd shed fragment of CR 2 isolated from Raji cell media, which contains the C3d-binding site

  5. Comprehensive Approach for Identifying the T Cell Subset Origin of CD3 and CD28 Antibody-Activated Chimeric Antigen Receptor-Modified T Cells.

    Science.gov (United States)

    Schmueck-Henneresse, Michael; Omer, Bilal; Shum, Thomas; Tashiro, Haruko; Mamonkin, Maksim; Lapteva, Natalia; Sharma, Sandhya; Rollins, Lisa; Dotti, Gianpietro; Reinke, Petra; Volk, Hans-Dieter; Rooney, Cliona M

    2017-07-01

    The outcome of therapy with chimeric Ag receptor (CAR)-modified T cells is strongly influenced by the subset origin of the infused T cells. However, because polyclonally activated T cells acquire a largely CD45RO + CCR7 - effector memory phenotype after expansion, regardless of subset origin, it is impossible to know which subsets contribute to the final T cell product. To determine the contribution of naive T cell, memory stem T cell, central memory T cell, effector memory T cell, and terminally differentiated effector T cell populations to the CD3 and CD28-activated CAR-modified T cells that we use for therapy, we followed the fate and function of individually sorted CAR-modified T cell subsets after activation with CD3 and CD28 Abs (CD3/28), transduction and culture alone, or after reconstitution into the relevant subset-depleted population. We show that all subsets are sensitive to CAR transduction, and each developed a distinct T cell functional profile during culture. Naive-derived T cells showed the greatest rate of proliferation but had more limited effector functions and reduced killing compared with memory-derived populations. When cultured in the presence of memory T cells, naive-derived T cells show increased differentiation, reduced effector cytokine production, and a reduced reproliferative response to CAR stimulation. CD3/28-activated T cells expanded in IL-7 and IL-15 produced greater expansion of memory stem T cells and central memory T cell-derived T cells compared with IL-2. Our strategy provides a powerful tool to elucidate the characteristics of CAR-modified T cells, regardless of the protocol used for expansion, reveals the functional properties of each expanded T cell subset, and paves the way for a more detailed evaluation of the effects of manufacturing changes on the subset contribution to in vitro-expanded T cells. Copyright © 2017 by The American Association of Immunologists, Inc.

  6. Metabolites of 5F-AKB-48, a synthetic cannabinoid receptor agonist, identified in human urine and liver microsomal preparations using liquid chromatography high-resolution mass spectrometry

    DEFF Research Database (Denmark)

    Holm, Niels Bjerre; Pedersen, Anders Just; Dalsgaard, Petur Weihe

    2015-01-01

    New types of synthetic cannabinoid designer drugs are constantly introduced to the illicit drug market to circumvent legislation. Recently, N-​(1-Adamant​yl)-​1-​(5-​fluoropentyl)-​1H-​indazole-​3-​carboxamide (5F-AKB-48), also known as 5F-APINACA, was identified as an adulterant in herbal products...

  7. Comprehensive fine mapping of chr12q12-14 and follow-up replication identify activin receptor 1B (ACVR1B) as a muscle strength gene

    NARCIS (Netherlands)

    Windelinckx, An; De Mars, Gunther; Huygens, Wim; Peeters, Maarten W.; Vincent, Barbara; Wijmenga, Cisca; Lambrechts, Diether; Delecluse, Christophe; Roth, Stephen M.; Metter, E. Jeffrey; Ferrucci, Luigi; Aerssens, Jeroen; Vlietinck, Robert; Beunen, Gaston P.; Thomis, Martine A.

    Muscle strength is important in functional activities of daily living and the prevention of common pathologies. We describe the two-staged fine mapping of a previously identified linkage peak for knee strength on chr12q12-14. First, 209 tagSNPs in/around 74 prioritized genes were genotyped in 500

  8. Neurological adverse events of new generation sodium blocker antiepileptic drugs. Meta-analysis of randomized, double-blinded studies with eslicarbazepine acetate, lacosamide and oxcarbazepine.

    Science.gov (United States)

    Zaccara, Gaetano; Giovannelli, Fabio; Maratea, Dario; Fadda, Valeria; Verrotti, Alberto

    2013-09-01

    Analysis of overall tolerability and neurological adverse effects (AEs) of eslicarbazepine acetate (ESL), lacosamide (LCM) and oxcarbazepine (OXC) from double-blind, placebo-controlled trials. Indirect comparisons of patients withdrawing because of AEs, and the incidence of some vestibulocerebellar AEs between these three antiepileptic dugs (AEDs). We searched MEDLINE for all randomized, double-blind, placebo-controlled trials investigating therapeutic effects of fixed oral doses of ESL, LCM and OXC in patients with drug resistant epilepsy. Withdrawal rate due to AEs, percentages of patients with serious AEs, and the proportion of patients experiencing any neurological AE, nausea and vomiting were assessed for their association with the experimental drug. Analyses were performed between recommended daily doses of each AED according to the approved summary of product characteristics (SPC). Risk differences were used to evaluate the association of any AE [99% confidence intervals (CIs)] or study withdrawals because of AEs (95% CIs) with the experimental drug. Indirect comparisons between withdrawal rate and AEs dizziness, coordination abnormal/ataxia and diplopia were estimated according to network meta-analysis (Net-MA). Eight randomized, placebo-controlled, double-blind trials (4 with ESL, 3 with LCM, and 1 with OXC) were included in our analysis. At high doses (OXC 1200mg, ESL 1200mg and LCM 400mg) there was an increased risk of AE-related study withdrawals compared to placebo for all drugs. Several AEs were associated with the experimental drug. Both number and frequency of AEs were dose-related. At high recommended doses, patients treated with OXC withdrew from the experimental treatment significantly more frequently than patients treated with ESL and LCM. Furthermore, the AEs coordination abnormal/ataxia and diplopia were significantly more frequently observed in patients treated with OXC compared to patients treated with LCM and ESL. The overall tolerability

  9. The recently identified P2Y-like receptor GPR17 is a sensor of brain damage and a new target for brain repair.

    Directory of Open Access Journals (Sweden)

    Davide Lecca

    Full Text Available Deciphering the mechanisms regulating the generation of new neurons and new oligodendrocytes, the myelinating cells of the central nervous system, is of paramount importance to address new strategies to replace endogenous damaged cells in the adult brain and foster repair in neurodegenerative diseases. Upon brain injury, the extracellular concentrations of nucleotides and cysteinyl-leukotrienes (cysLTs, two families of endogenous signaling molecules, are markedly increased at the site of damage, suggesting that they may act as "danger signals" to alert responses to tissue damage and start repair. Here we show that, in brain telencephalon, GPR17, a recently deorphanized receptor for both uracil nucleotides and cysLTs (e.g., UDP-glucose and LTD(4, is normally present on neurons and on a subset of parenchymal quiescent oligodendrocyte precursor cells. We also show that induction of brain injury using an established focal ischemia model in the rodent induces profound spatiotemporal-dependent changes of GPR17. In the lesioned area, we observed an early and transient up-regulation of GPR17 in neurons expressing the cellular stress marker heat shock protein 70. Magnetic Resonance Imaging in living mice showed that the in vivo pharmacological or biotechnological knock down of GPR17 markedly prevents brain infarct evolution, suggesting GPR17 as a mediator of neuronal death at this early ischemic stage. At later times after ischemia, GPR17 immuno-labeling appeared on microglia/macrophages infiltrating the lesioned area to indicate that GPR17 may also acts as a player in the remodeling of brain circuitries by microglia. At this later stage, parenchymal GPR17+ oligodendrocyte progenitors started proliferating in the peri-injured area, suggesting initiation of remyelination. To confirm a specific role for GPR17 in oligodendrocyte differentiation, the in vitro exposure of cortical pre-oligodendrocytes to the GPR17 endogenous ligands UDP-glucose and LTD(4

  10. Genome-wide gene-environment study identifies glutamate receptor gene GRIN2A as a Parkinson's disease modifier gene via interaction with coffee.

    OpenAIRE

    Taye H Hamza; Honglei Chen; Erin M Hill-Burns; Shannon L Rhodes; Jennifer Montimurro; Denise M Kay; Albert Tenesa; Victoria I Kusel; Patricia Sheehan; Muthukrishnan Eaaswarkhanth; Dora Yearout; Ali Samii; John W Roberts; Pinky Agarwal; Yvette Bordelon

    2011-01-01

    Our aim was to identify genes that influence the inverse association of coffee with the risk of developing Parkinson's disease (PD). We used genome-wide genotype data and lifetime caffeinated-coffee-consumption data on 1,458 persons with PD and 931 without PD from the NeuroGenetics Research Consortium (NGRC), and we performed a genome-wide association and interaction study (GWAIS), testing each SNP's main-effect plus its interaction with coffee, adjusting for sex, age, and two principal compo...

  11. Metabolites of 5F-AKB-48, a synthetic cannabinoid receptor agonist, identified in human urine and liver microsomal preparations using liquid chromatography high-resolution mass spectrometry.

    Science.gov (United States)

    Holm, Niels Bjerre; Pedersen, Anders Just; Dalsgaard, Petur Weihe; Linnet, Kristian

    2015-03-01

    New types of synthetic cannabinoid designer drugs are constantly introduced to the illicit drug market to circumvent legislation. Recently, N-​(1-Adamant​yl)-​1-​(5-​fluoropentyl)-​1H-​indazole-​3-​carboxamide (5F-AKB-48), also known as 5F-APINACA, was identified as an adulterant in herbal products. This compound deviates from earlier JHW-type synthetic cannabinoids by having an indazole ring connected to an adamantyl group via a carboxamide linkage. Synthetic cannabinoids are completely metabolized, and identification of the metabolites is thus crucial when using urine as the sample matrix. Using an authentic urine sample and high-resolution accurate-mass Fourier transform Orbitrap mass spectrometry, we identified 16 phase-I metabolites of 5F-AKB-48. The modifications included mono-, di-, and trihydroxylation on the adamantyl ring alone or in combination with hydroxylation on the N-fluoropentylindazole moiety, dealkylation of the N-fluoropentyl side chain, and oxidative loss of fluorine as well as combinations thereof. The results were compared to human liver microsomal (HLM) incubations, which predominantly showed time-dependent formation of mono-, di-, and trihydroxylated metabolites having the hydroxyl groups on the adamantyl ring. The results presented here may be used to select metabolites specific of 5F-AKB-48 for use in clinical and forensic screening. Copyright © 2014 John Wiley & Sons, Ltd.

  12. T Cell Receptor Vβ Staining Identifies the Malignant Clone in Adult T cell Leukemia and Reveals Killing of Leukemia Cells by Autologous CD8+ T cells.

    Directory of Open Access Journals (Sweden)

    Aileen G Rowan

    2016-11-01

    Full Text Available There is growing evidence that CD8+ cytotoxic T lymphocyte (CTL responses can contribute to long-term remission of many malignancies. The etiological agent of adult T-cell leukemia/lymphoma (ATL, human T lymphotropic virus type-1 (HTLV-1, contains highly immunogenic CTL epitopes, but ATL patients typically have low frequencies of cytokine-producing HTLV-1-specific CD8+ cells in the circulation. It remains unclear whether patients with ATL possess CTLs that can kill the malignant HTLV-1 infected clone. Here we used flow cytometric staining of TCRVβ and cell adhesion molecule-1 (CADM1 to identify monoclonal populations of HTLV-1-infected T cells in the peripheral blood of patients with ATL. Thus, we quantified the rate of CD8+-mediated killing of the putative malignant clone in ex vivo blood samples. We observed that CD8+ cells from ATL patients were unable to lyse autologous ATL clones when tested directly ex vivo. However, short in vitro culture restored the ability of CD8+ cells to kill ex vivo ATL clones in some donors. The capacity of CD8+ cells to lyse HTLV-1 infected cells which expressed the viral sense strand gene products was significantly enhanced after in vitro culture, and donors with an ATL clone that expressed the HTLV-1 Tax gene were most likely to make a detectable lytic CD8+ response to the ATL cells. We conclude that some patients with ATL possess functional tumour-specific CTLs which could be exploited to contribute to control of the disease.

  13. Insulin receptors

    International Nuclear Information System (INIS)

    Kahn, C.R.; Harrison, L.C.

    1988-01-01

    This book contains the proceedings on insulin receptors. Part A: Methods for the study of structure and function. Topics covered include: Method for purification and labeling of insulin receptors, the insulin receptor kinase, and insulin receptors on special tissues

  14. Transcriptional profiling reveals molecular signatures associated with HIV permissiveness in Th1Th17 cells and identifies Peroxisome Proliferator-Activated Receptor Gamma as an intrinsic negative regulator of viral replication

    Science.gov (United States)

    2013-01-01

    Background We previously demonstrated that primary Th1Th17 cells are highly permissive to HIV-1, whereas Th1 cells are relatively resistant. Molecular mechanisms underlying these differences remain unknown. Results Exposure to replication competent and single-round VSV-G pseudotyped HIV strains provide evidence that superior HIV replication in Th1Th17 vs. Th1 cells was regulated by mechanisms located at entry and post-entry levels. Genome-wide transcriptional profiling identified transcripts upregulated (n = 264) and downregulated (n = 235) in Th1Th17 vs. Th1 cells (p-value Th17 (nuclear receptors, trafficking, p38/MAPK, NF-κB, p53/Ras, IL-23) vs. Th1 cells (proteasome, interferon α/β). Differentially expressed genes were classified into biological categories using Gene Ontology. Th1Th17 cells expressed typical Th17 markers (IL-17A/F, IL-22, CCL20, RORC, IL-26, IL-23R, CCR6) and transcripts functionally linked to regulating cell trafficking (CEACAM1, MCAM), activation (CD28, CD40LG, TNFSF13B, TNFSF25, PTPN13, MAP3K4, LTB, CTSH), transcription (PPARγ, RUNX1, ATF5, ARNTL), apoptosis (FASLG), and HIV infection (CXCR6, FURIN). Differential expression of CXCR6, PPARγ, ARNTL, PTPN13, MAP3K4, CTSH, SERPINB6, PTK2, and ISG20 was validated by RT-PCR, flow cytometry and/or confocal microscopy. The nuclear receptor PPARγ was preferentially expressed by Th1Th17 cells. PPARγ RNA interference significantly increased HIV replication at levels post-entry and prior HIV-DNA integration. Finally, the activation of PPARγ pathway via the agonist Rosiglitazone induced the nuclear translocation of PPARγ and a robust inhibition of viral replication. Conclusions Thus, transcriptional profiling in Th1Th17 vs. Th1 cells demonstrated that HIV permissiveness is associated with a superior state of cellular activation and limited antiviral properties and identified PPARγ as an intrinsic negative regulator of viral replication. Therefore, triggering PPARγ pathway via non

  15. Fine mapping of a dominantly inherited powdery mildew resistance major-effect QTL, Pm1.1, in cucumber identifies a 41.1 kb region containing two tandemly arrayed cysteine-rich receptor-like protein kinase genes.

    Science.gov (United States)

    Xu, Xuewen; Yu, Ting; Xu, Ruixue; Shi, Yang; Lin, Xiaojian; Xu, Qiang; Qi, Xiaohua; Weng, Yiqun; Chen, Xuehao

    2016-03-01

    A dominantly inherited major-effect QTL for powdery mildew resistance in cucumber was fine mapped. Two tandemly arrayed cysteine-rich receptor-like protein kinase genes were identified as the most possible candidates. Powdery mildew (PM) is one of the most severe fungal diseases of cucumber (Cucumis sativus L.) and other cucurbit crops, but the molecular genetic mechanisms of powdery mildew resistance in cucurbits are still poorly understood. In this study, through marker-assisted backcrossing with an elite cucumber inbred line, D8 (PM susceptible), we developed a single-segment substitution line, SSSL0.7, carrying 95 kb fragment from PM resistance donor, Jin5-508, that was defined by two microsatellite markers, SSR16472 and SSR16881. A segregating population with 3600 F2 plants was developed from the SSSL0.7 × D8 mating; segregation analysis confirmed a dominantly inherited major-effect QTL, Pm1.1 in cucumber chromosome 1 underlying PM resistance in SSSL0.7. New molecular markers were developed through exploring the next generation resequenced genomes of Jin5-508 and D8. Linkage analysis and QTL mapping in a subset of the F2 plants delimited the Pm1.1 locus into a 41.1 kb region, in which eight genes were predicted. Comparative gene expression analysis revealed that two concatenated genes, Csa1M064780 and Csa1M064790 encoding the same function of a cysteine-rich receptor-like protein kinase, were the most likely candidate genes. GFP fusion protein-aided subcellular localization indicated that both candidate genes were located in the plasma membrane, but Csa1M064780 was also found in the nucleus. This is the first report of dominantly inherited PM resistance in cucumber. Results of this study will provide new insights into understanding the phenotypic and genetic mechanisms of PM resistance in cucumber. This work should also facilitate marker-assisted selection in cucumber breeding for PM resistance.

  16. Somatostatin receptors

    DEFF Research Database (Denmark)

    Møller, Lars Neisig; Stidsen, Carsten Enggaard; Hartmann, Bolette

    2003-01-01

    functional units, receptors co-operate. The total receptor apparatus of individual cell types is composed of different-ligand receptors (e.g. SRIF and non-SRIF receptors) and co-expressed receptor subtypes (e.g. sst(2) and sst(5) receptors) in characteristic proportions. In other words, levels of individual......-peptides, receptor agonists and antagonists. Relatively long half lives, as compared to those of the endogenous ligands, have been paramount from the outset. Motivated by theoretical puzzles or the shortcomings of present-day diagnostics and therapy, investigators have also aimed to produce subtype...

  17. Hybrid Capture-Based Comprehensive Genomic Profiling Identifies Lung Cancer Patients with Well-Characterized Sensitizing Epidermal Growth Factor Receptor Point Mutations That Were Not Detected by Standard of Care Testing.

    Science.gov (United States)

    Suh, James H; Schrock, Alexa B; Johnson, Adrienne; Lipson, Doron; Gay, Laurie M; Ramkissoon, Shakti; Vergilio, Jo-Anne; Elvin, Julia A; Shakir, Abdur; Ruehlman, Peter; Reckamp, Karen L; Ou, Sai-Hong Ignatius; Ross, Jeffrey S; Stephens, Philip J; Miller, Vincent A; Ali, Siraj M

    2018-03-14

    In our recent study, of cases positive for epidermal growth factor receptor ( EGFR ) exon 19 deletions using comprehensive genomic profiling (CGP), 17/77 (22%) patients with prior standard of care (SOC) EGFR testing results available were previously negative for exon 19 deletion. Our aim was to compare the detection rates of CGP versus SOC testing for well-characterized sensitizing EGFR point mutations (pm) in our 6,832-patient cohort. DNA was extracted from 40 microns of formalin-fixed paraffin-embedded sections from 6,832 consecutive cases of non-small cell lung cancer (NSCLC) of various histologies (2012-2015). CGP was performed using a hybrid capture, adaptor ligation-based next-generation sequencing assay to a mean coverage depth of 576×. Genomic alterations (pm, small indels, copy number changes and rearrangements) involving EGFR were recorded for each case and compared with prior testing results if available. Overall, there were 482 instances of EGFR exon 21 L858R (359) and L861Q (20), exon 18 G719X (73) and exon 20 S768I (30) pm, of which 103 unique cases had prior EGFR testing results that were available for review. Of these 103 cases, CGP identified 22 patients (21%) with sensitizing EGFR pm that were not detected by SOC testing, including 9/75 (12%) patients with L858R, 4/7 (57%) patients with L861Q, 8/20 (40%) patients with G719X, and 4/7 (57%) patients with S768I pm (some patients had multiple EGFR pm). In cases with available clinical data, benefit from small molecule inhibitor therapy was observed. CGP, even when applied to low tumor purity clinical-grade specimens, can detect well-known EGFR pm in NSCLC patients that would otherwise not be detected by SOC testing. Taken together with EGFR exon 19 deletions, over 20% of patients who are positive for EGFR -activating mutations using CGP are previously negative by SOC EGFR mutation testing, suggesting that thousands of such patients per year in the U.S. alone could experience improved clinical

  18. Proteomic profiling of triple-negative breast carcinomas in combination with a three-tier orthogonal technology approach identifies Mage-A4 as potential therapeutic target in estrogen receptor negative breast cancer

    DEFF Research Database (Denmark)

    Cabezón, Teresa; Gromova, Irina; Gromov, Pavel

    2013-01-01

    Breast cancer is a very heterogeneous disease, encompassing several intrinsic subtypes with various morphological and molecular features, natural history and response to therapy. Currently, molecular targeted therapies are available for estrogen receptor (ER)(-) and human epidermal growth factor ...

  19. The combination of Ki67, histological grade and estrogen receptor status identifies a low-risk group among 1,854 chemo-naïve women with N0/N1 primary breast cancer

    DEFF Research Database (Denmark)

    Strand, Carina; Bak, Martin; Borgquist, Signe

    2013-01-01

    The aim was to confirm a previously defined prognostic index, combining a proliferation marker, histological grade, and estrogen receptor (ER) in different subsets of primary N0/N1 chemo-naïve breast cancer patients.......The aim was to confirm a previously defined prognostic index, combining a proliferation marker, histological grade, and estrogen receptor (ER) in different subsets of primary N0/N1 chemo-naïve breast cancer patients....

  20. A biallelic RFLP of the human. alpha. 2-C4 adrenergic receptor gene (ADRA2RL2) localized on the short arm of chromosome 4 and encoding the putative. alpha. 2B receptor is identified with Bsu 36 L using a 1. 5 kb probe (p ADRA2RL2)

    Energy Technology Data Exchange (ETDEWEB)

    Hoeche, M.R.; Berrettini, W.H. (Clinical Neurogenetics Branch, Bethesda, MD (USA)); Regan, J.W. (Duke Univ. Medical Center, Durham, NC (USA))

    1989-12-11

    A 1.5 kb Eco RI cDNA fragment representing the human alpha2-C4 adrenergic receptor (AR) gene encoding the putative alpha2B-AR, containing approximately 1270 bp of the coding and 240 bp of the 3{prime}flanking region, inserted into pSP65, was used as a probe (p ADRA2RL2). This clone was obtained by screening a human kidney lambda GT10 cDNA library with the 0.95 kb Pst I restriction fragment derived from the coding block of the gene for the human platelet alpha2-AR. Hybridization of human genomic DNA digested with Bsu 36 I identifies a two allele polymorphism with bands at 12 kb and 5.8 kb. 20 unrelated North American caucasian subjects were evaluated with frequencies of: A allele, 0.45; B allele, 0.55, heterozygosity (obs), 0.5. This alpha2-AR gene has been mapped in a separation effort in 59 CEPH reference pedigrees to the tip of the short arm of chromosome 4 just proximal to GB (4p 16.3) reported to be linked to the Huntingston's disease gene. Codominant inheritance was observed in seven families with two and three generations, respectively. The number of meioses scored was 95.

  1. Receptor assay

    Energy Technology Data Exchange (ETDEWEB)

    Kato, K; Ibayashi, H [Kyushu Univ., Fukuoka (Japan). Faculty of Medicine

    1975-05-01

    This paper summarized present status and problems of analysis of hormone receptor and a few considerations on clinical significance of receptor abnormalities. It was pointed that in future clinical field quantitative and qualitative analysis of receptor did not remain only in the etiological discussion, but that it was an epoch-making field of investigation which contained the possiblity of artificial change of sensitivity of living body on drugs and the development connected directly with treatment of various diseases.

  2. Fibroblast growth factor receptors in breast cancer.

    Science.gov (United States)

    Wang, Shuwei; Ding, Zhongyang

    2017-05-01

    Fibroblast growth factor receptors are growth factor receptor tyrosine kinases, exerting their roles in embryogenesis, tissue homeostasis, and development of breast cancer. Recent genetic studies have identified some subtypes of fibroblast growth factor receptors as strong genetic loci associated with breast cancer. In this article, we review the recent epidemiological findings and experiment results of fibroblast growth factor receptors in breast cancer. First, we summarized the structure and physiological function of fibroblast growth factor receptors in humans. Then, we discussed the common genetic variations in fibroblast growth factor receptors that affect breast cancer risk. In addition, we also introduced the potential roles of each fibroblast growth factor receptors isoform in breast cancer. Finally, we explored the potential therapeutics targeting fibroblast growth factor receptors for breast cancer. Based on the biological mechanisms of fibroblast growth factor receptors leading to the pathogenesis in breast cancer, targeting fibroblast growth factor receptors may provide new opportunities for breast cancer therapeutic strategies.

  3. Melatonin Receptor Genes in Vertebrates

    Directory of Open Access Journals (Sweden)

    Hua Dong Yin

    2013-05-01

    Full Text Available Melatonin receptors are members of the G protein-coupled receptor (GPCR family. Three genes for melatonin receptors have been cloned. The MT1 (or Mel1a or MTNR1A and MT2 (or Mel1b or MTNR1B receptor subtypes are present in humans and other mammals, while an additional melatonin receptor subtype, Mel1c (or MTNR1C, has been identified in fish, amphibians and birds. Another melatonin related orphan receptor, GPR50, which does not bind melatonin, is found exclusively in mammals. The hormone melatonin is secreted primarily by the pineal gland, with highest levels occurring during the dark period of a circadian cycle. This hormone acts systemically in numerous organs. In the brain, it is involved in the regulation of various neural and endocrine processes, and it readjusts the circadian pacemaker, the suprachiasmatic nucleus. This article reviews recent studies of gene organization, expression, evolution and mutations of melatonin receptor genes of vertebrates. Gene polymorphisms reveal that numerous mutations are associated with diseases and disorders. The phylogenetic analysis of receptor genes indicates that GPR50 is an outgroup to all other melatonin receptor sequences. GPR50 may have separated from a melatonin receptor ancestor before the split between MTNR1C and the MTNR1A/B ancestor.

  4. A new family of insect tyramine receptors

    DEFF Research Database (Denmark)

    Cazzamali, Giuseppe; Klærke, Dan Arne; Grimmelikhuijzen, Cornelis J P

    2005-01-01

    in the genomic databases from the malaria mosquito Anopheles gambiae and the honeybee Apis mellifera. These four tyramine or tyramine-like receptors constitute a new receptor family that is phylogenetically distinct from the previously identified insect octopamine/tyramine receptors. The Drosophila tyramine...

  5. Scavenger receptors in homeostasis and immunity.

    Science.gov (United States)

    Canton, Johnathan; Neculai, Dante; Grinstein, Sergio

    2013-09-01

    Scavenger receptors were originally identified by their ability to recognize and to remove modified lipoproteins; however, it is now appreciated that they carry out a striking range of functions, including pathogen clearance, lipid transport, the transport of cargo within the cell and even functioning as taste receptors. The large repertoire of ligands recognized by scavenger receptors and their broad range of functions are not only due to the wide range of receptors that constitute this family but also to their ability to partner with various co-receptors. The ability of individual scavenger receptors to associate with different co-receptors makes their responsiveness extremely versatile. This Review highlights recent insights into the structural features that determine the function of scavenger receptors and the emerging role that these receptors have in immune responses, notably in macrophage polarization and in the pathogenesis of diseases such as atherosclerosis and Alzheimer's disease.

  6. TLX: An elusive receptor.

    Science.gov (United States)

    Benod, Cindy; Villagomez, Rosa; Webb, Paul

    2016-03-01

    TLX (tailless receptor) is a member of the nuclear receptor superfamily and belongs to a class of nuclear receptors for which no endogenous or synthetic ligands have yet been identified. TLX is a promising therapeutic target in neurological disorders and brain tumors. Thus, regulatory ligands for TLX need to be identified to complete the validation of TLX as a useful target and would serve as chemical probes to pursue the study of this receptor in disease models. It has recently been proved that TLX is druggable. However, to identify potent and specific TLX ligands with desirable biological activity, a deeper understanding of where ligands bind, how they alter TLX conformation and of the mechanism by which TLX mediates the transcription of its target genes is needed. While TLX is in the process of escaping from orphanhood, future ligand design needs to progress in parallel with improved understanding of (i) the binding cavity or surfaces to target with small molecules on the TLX ligand binding domain and (ii) the nature of the TLX coregulators in particular cell and disease contexts. Both of these topics are discussed in this review. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Transcriptional regulators transforming growth factor-beta 1 and estrogen-related receptor-alpha identified as putative mediators of calf rumen epithelial tissue development and function during weaning

    Science.gov (United States)

    Molecular mechanisms controlling rumen epithelial development at weaning remain largely unknown. To identify gene networks and regulatory factors responsive to concentrate versus forage feeding at weaning, Holstein bull calves (n = 18) were fed commercial milk replacer only (MRO) until 42 d of age. ...

  8. The repertoire of trace amine G-protein-coupled receptors

    DEFF Research Database (Denmark)

    Gloriam, David E.; Bjarnadóttir, Thóra K; Yan, Yi-Lin

    2005-01-01

    eukaryotic species for receptors similar to the mammalian trace amine (TA) receptor subfamily. We identified 18 new receptors in rodents that are orthologous to the previously known TA-receptors. Remarkably, we found 57 receptors (and 40 pseudogenes) of this type in the zebrafish (Danio rerio), while fugu...... (Takifugu rubripes) had only eight receptors (and seven pseudogenes). We mapped 47 of the zebrafish TA-receptors on chromosomes using radiation hybrid panels and meiotic mapping. The results, together with the degree of conservation and phylogenetic relationships displayed among the zebrafish receptors...

  9. Receptor autoradiography in the hippocampus of man and rat

    International Nuclear Information System (INIS)

    Zilles, K.

    1988-01-01

    This chapter deals with the following questions: regional distribution of binding sites for 5-HT, glutamate, and acetylcholine in Ammon's horn and the dentate gyrus of rat and human brain; comparison of receptor distribution and neuronal pathways with identified transmitters; correlation of region-specific densities between different receptors and receptor subtypes (colocalization of different receptors on the level of hippocampal layers) and comparison of receptor distribution in human and rat hippocampus

  10. XMRV: usage of receptors and potential co-receptors

    Directory of Open Access Journals (Sweden)

    Gaddam Durga

    2011-09-01

    Full Text Available Abstract Background XMRV is a gammaretrovirus first identified in prostate tissues of Prostate Cancer (PC patients and later in the blood cells of patients with Chronic Fatigue Syndrome (CFS. Although XMRV is thought to use XPR1 for cell entry, it infects A549 cells that do not express XPR1, suggesting usage of other receptors or co-receptors. Methods To study the usage of different receptors and co- receptors that could play a role in XMRV infection of lymphoid cells and GHOST (GFP- Human osteosarcoma cells expressing CD4 along with different chemokine receptors including CCR1, CCR2, etc., were infected with XMRV. Culture supernatants and cells were tested for XMRV replication using real time quantitative PCR. Results Infection and replication of XMRV was seen in a variety of GHOST cells, LNCaP, DU145, A549 and Caski cell lines. The levels of XMRV replication varied in different cell lines showing differential replication in different cell lines. However, replication in A549 which lacks XPR1 expression was relatively higher than DU145 but lower than, LNCaP. XMRV replication varied in GHOST cell lines expressing CD4 and each of the co- receptors CCR1-CCR8 and bob. There was significant replication of XMRV in CCR3 and Bonzo although it is much lower when compared to DU145, A549 and LNCaP. Conclusion XMRV replication was observed in GHOST cells that express CD4 and each of the chemokine receptors ranging from CCR1- CCR8 and BOB suggesting that infectivity in hematopoietic cells could be mediated by use of these receptors.

  11. The LDL receptor.

    Science.gov (United States)

    Goldstein, Joseph L; Brown, Michael S

    2009-04-01

    In this article, the history of the LDL receptor is recounted by its codiscoverers. Their early work on the LDL receptor explained a genetic cause of heart attacks and led to new ways of thinking about cholesterol metabolism. The LDL receptor discovery also introduced three general concepts to cell biology: receptor-mediated endocytosis, receptor recycling, and feedback regulation of receptors. The latter concept provides the mechanism by which statins selectively lower plasma LDL, reducing heart attacks and prolonging life.

  12. Expression of GABAergic receptors in mouse taste receptor cells.

    Directory of Open Access Journals (Sweden)

    Margaret R Starostik

    Full Text Available BACKGROUND: Multiple excitatory neurotransmitters have been identified in the mammalian taste transduction, with few studies focused on inhibitory neurotransmitters. Since the synthetic enzyme glutamate decarboxylase (GAD for gamma-aminobutyric acid (GABA is expressed in a subset of mouse taste cells, we hypothesized that other components of the GABA signaling pathway are likely expressed in this system. GABA signaling is initiated by the activation of either ionotropic receptors (GABA(A and GABA(C or metabotropic receptors (GABA(B while it is terminated by the re-uptake of GABA through transporters (GATs. METHODOLOGY/PRINCIPAL FINDINGS: Using reverse transcriptase-PCR (RT-PCR analysis, we investigated the expression of different GABA signaling molecules in the mouse taste system. Taste receptor cells (TRCs in the circumvallate papillae express multiple subunits of the GABA(A and GABA(B receptors as well as multiple GATs. Immunocytochemical analyses examined the distribution of the GABA machinery in the circumvallate papillae. Both GABA(A-and GABA(B- immunoreactivity were detected in the peripheral taste receptor cells. We also used transgenic mice that express green fluorescent protein (GFP in either the Type II taste cells, which can respond to bitter, sweet or umami taste stimuli, or in the Type III GAD67 expressing taste cells. Thus, we were able to identify that GABAergic receptors are expressed in some Type II and Type III taste cells. Mouse GAT4 labeling was concentrated in the cells surrounding the taste buds with a few positively labeled TRCs at the margins of the taste buds. CONCLUSIONS/SIGNIFICANCE: The presence of GABAergic receptors localized on Type II and Type III taste cells suggests that GABA is likely modulating evoked taste responses in the mouse taste bud.

  13. Identification and mechanism of ABA receptor antagonism

    KAUST Repository

    Melcher, Karsten; Xu, Yong; Ng, Ley-Moy; Zhou, X. Edward; Soon, Fen-Fen; Chinnusamy, Viswanathan; Suino-Powell, Kelly M.; Kovach, Amanda; Tham, Fook S.; Cutler, Sean R.; Li, Jun; Yong, Eu-Leong; Zhu, Jian-Kang; Xu, H. Eric

    2010-01-01

    The phytohormone abscisic acid (ABA) functions through a family of fourteen PYR/PYL receptors, which were identified by resistance to pyrabactin, a synthetic inhibitor of seed germination. ABA activates these receptors to inhibit type 2C protein phosphatases, such as ABI1, yet it remains unclear whether these receptors can be antagonized. Here we demonstrate that pyrabactin is an agonist of PYR1 and PYL1 but is unexpectedly an antagonist of PYL2. Crystal structures of the PYL2-pyrabactin and PYL1-pyrabactin-ABI1 complexes reveal the mechanism responsible for receptor-selective activation and inhibition, which enables us to design mutations that convert PYL1 to a pyrabactin-inhibited receptor and PYL2 to a pyrabactin-activated receptor and to identify new pyrabactin-based ABA receptor agonists. Together, our results establish a new concept of ABA receptor antagonism, illustrate its underlying mechanisms and provide a rational framework for discovering novel ABA receptor ligands. © 2010 Nature America, Inc. All rights reserved.

  14. Identification and mechanism of ABA receptor antagonism

    KAUST Repository

    Melcher, Karsten

    2010-08-22

    The phytohormone abscisic acid (ABA) functions through a family of fourteen PYR/PYL receptors, which were identified by resistance to pyrabactin, a synthetic inhibitor of seed germination. ABA activates these receptors to inhibit type 2C protein phosphatases, such as ABI1, yet it remains unclear whether these receptors can be antagonized. Here we demonstrate that pyrabactin is an agonist of PYR1 and PYL1 but is unexpectedly an antagonist of PYL2. Crystal structures of the PYL2-pyrabactin and PYL1-pyrabactin-ABI1 complexes reveal the mechanism responsible for receptor-selective activation and inhibition, which enables us to design mutations that convert PYL1 to a pyrabactin-inhibited receptor and PYL2 to a pyrabactin-activated receptor and to identify new pyrabactin-based ABA receptor agonists. Together, our results establish a new concept of ABA receptor antagonism, illustrate its underlying mechanisms and provide a rational framework for discovering novel ABA receptor ligands. © 2010 Nature America, Inc. All rights reserved.

  15. Characteristic molecular vibrations of adenosine receptor ligands.

    Science.gov (United States)

    Chee, Hyun Keun; Yang, Jin-San; Joung, Je-Gun; Zhang, Byoung-Tak; Oh, S June

    2015-02-13

    Although the regulation of membrane receptor activation is known to be crucial for molecular signal transduction, the molecular mechanism underlying receptor activation is not fully elucidated. Here we study the physicochemical nature of membrane receptor behavior by investigating the characteristic molecular vibrations of receptor ligands using computational chemistry and informatics methods. By using information gain, t-tests, and support vector machines, we have identified highly informative features of adenosine receptor (AdoR) ligand and corresponding functional amino acid residues such as Asn (6.55) of AdoR that has informative significance and is indispensable for ligand recognition of AdoRs. These findings may provide new perspectives and insights into the fundamental mechanism of class A G protein-coupled receptor activation. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  16. Ecdysteroid receptors in Drosophila melanogaster adult females

    Science.gov (United States)

    Ecdysteroid receptors were identified and partially characterized from total cell extracts of whole animals and dissected tissues from Drosophila melanogaster adult females. Binding studies indicated the presence of two ecdysteroid binding components having high affinity and specificity consistent w...

  17. FMRFamide receptors of Helix aspersa

    International Nuclear Information System (INIS)

    Payza, K.

    1988-01-01

    A receptor binding assay and an isolated heart bioassay were used to identify and characterize the FMRFamide receptors in Helix. In the heart bioassay, FMRFamide increased myocardial contraction force. A potent FMRFamide analog, desaminoTyr-Phe-norLeu-arg-Phe-amide (daYFnLRFamide), was used as a radioiodinated receptor ligand. The high affinity binding of 125 I-daYFnLRFamide at 0 degree C to Helix brain membranes was reversible, saturable, pH-dependent and specific, with a K D of 13-14 nM. A lower affinity (245 nM) site was also observed. Radioligand binding sites were also identified in the heart, male reproductive organs and digestive organs. The structure-activity relations (SAR) of cardiostimulation correlated with the specificity of 125 I-daYFnLRFamide binding to brain and heart receptors. The SAR were similar to those of other molluscan FMRFamide bioassays, except that they showed a marked preference for some analogs with blocked amino-terminals

  18. Receptor-receptor interactions within receptor mosaics. Impact on neuropsychopharmacology.

    Science.gov (United States)

    Fuxe, K; Marcellino, D; Rivera, A; Diaz-Cabiale, Z; Filip, M; Gago, B; Roberts, D C S; Langel, U; Genedani, S; Ferraro, L; de la Calle, A; Narvaez, J; Tanganelli, S; Woods, A; Agnati, L F

    2008-08-01

    Future therapies for diseases associated with altered dopaminergic signaling, including Parkinson's disease, schizophrenia and drug addiction or drug dependence may substantially build on the existence of intramembrane receptor-receptor interactions within dopamine receptor containing receptor mosaics (RM; dimeric or high-order receptor oligomers) where it is believed that the dopamine D(2) receptor may operate as the 'hub receptor' within these complexes. The constitutive adenosine A(2A)/dopamine D(2) RM, located in the dorsal striato-pallidal GABA neurons, are of particular interest in view of the demonstrated antagonistic A(2A)/D(2) interaction within these heteromers; an interaction that led to the suggestion and later demonstration that A(2A) antagonists could be used as novel anti-Parkinsonian drugs. Based on the likely existence of A(2A)/D(2)/mGluR5 RM located both extrasynaptically on striato-pallidal GABA neurons and on cortico-striatal glutamate terminals, multiple receptor-receptor interactions within this RM involving synergism between A(2A)/mGluR5 to counteract D(2) signaling, has led to the proposal of using combined mGluR5 and A(2A) antagonists as a future anti-Parkinsonian treatment. Based on the same RM in the ventral striato-pallidal GABA pathways, novel strategies for the treatment of schizophrenia, building on the idea that A(2A) agonists and/or mGluR5 agonists will help reduce the increased dopaminergic signaling associated with this disease, have been suggested. Such treatment may ensure the proper glutamatergic drive from the mediodorsal thalamic nucleus to the prefrontal cortex, one which is believed to be reduced in schizophrenia due to a dominance of D(2)-like signaling in the ventral striatum. Recently, A(2A) receptors also have been shown to counteract the locomotor and sensitizing actions of cocaine and increases in A(2A) receptors have also been observed in the nucleus accumbens after extended cocaine self-administration, probably

  19. Acetylcholine receptor antibody

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003576.htm Acetylcholine receptor antibody To use the sharing features on this page, please enable JavaScript. Acetylcholine receptor antibody is a protein found in the blood of ...

  20. Cooperative ethylene receptor signaling

    OpenAIRE

    Liu, Qian; Wen, Chi-Kuang

    2012-01-01

    The gaseous plant hormone ethylene is perceived by a family of five ethylene receptor members in the dicotyledonous model plant Arabidopsis. Genetic and biochemical studies suggest that the ethylene response is suppressed by ethylene receptor complexes, but the biochemical nature of the receptor signal is unknown. Without appropriate biochemical measures to trace the ethylene receptor signal and quantify the signal strength, the biological significance of the modulation of ethylene responses ...

  1. Thoughts on identifiers

    CERN Multimedia

    CERN. Geneva

    2005-01-01

    As business processes and information transactions have become an inextricably intertwined with the Web, the importance of assignment, registration, discovery, and maintenance of identifiers has increased. In spite of this, integrated frameworks for managing identifiers have been slow to emerge. Instead, identification systems arise (quite naturally) from immediate business needs without consideration for how they fit into larger information architectures. In addition, many legacy identifier systems further complicate the landscape, making it difficult for content managers to select and deploy identifier systems that meet both the business case and long term information management objectives. This presentation will outline a model for evaluating identifier applications and the functional requirements of the systems necessary to support them. The model is based on a layered analysis of the characteristics of identifier systems, including: * Functional characteristics * Technology * Policy * Business * Social T...

  2. Identifiability in stochastic models

    CERN Document Server

    1992-01-01

    The problem of identifiability is basic to all statistical methods and data analysis, occurring in such diverse areas as Reliability Theory, Survival Analysis, and Econometrics, where stochastic modeling is widely used. Mathematics dealing with identifiability per se is closely related to the so-called branch of ""characterization problems"" in Probability Theory. This book brings together relevant material on identifiability as it occurs in these diverse fields.

  3. The alpha-fetoprotein third domain receptor binding fragment: in search of scavenger and associated receptor targets.

    Science.gov (United States)

    Mizejewski, G J

    2015-01-01

    Recent studies have demonstrated that the carboxyterminal third domain of alpha-fetoprotein (AFP-CD) binds with various ligands and receptors. Reports within the last decade have established that AFP-CD contains a large fragment of amino acids that interact with several different receptor types. Using computer software specifically designed to identify protein-to-protein interaction at amino acid sequence docking sites, the computer searches identified several types of scavenger-associated receptors and their amino acid sequence locations on the AFP-CD polypeptide chain. The scavenger receptors (SRs) identified were CD36, CD163, Stabilin, SSC5D, SRB1 and SREC; the SR-associated receptors included the mannose, low-density lipoprotein receptors, the asialoglycoprotein receptor, and the receptor for advanced glycation endproducts (RAGE). Interestingly, some SR interaction sites were localized on the AFP-derived Growth Inhibitory Peptide (GIP) segment at amino acids #480-500. Following the detection studies, a structural subdomain analysis of both the receptor and the AFP-CD revealed the presence of epidermal growth factor (EGF) repeats, extracellular matrix-like protein regions, amino acid-rich motifs and dimerization subdomains. For the first time, it was reported that EGF-like sequence repeats were identified on each of the three domains of AFP. Thereafter, the localization of receptors on specific cell types were reviewed and their functions were discussed.

  4. Radiolabelled GLP-1 receptor antagonist binds to GLP-1 receptor-expressing human tissues

    Energy Technology Data Exchange (ETDEWEB)

    Waser, Beatrice; Reubi, Jean Claude [University of Berne, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, PO Box 62, Berne (Switzerland)

    2014-06-15

    Radiolabelled glucagon-like peptide 1 (GLP-1) receptor agonists have recently been shown to successfully image benign insulinomas in patients. For the somatostatin receptor targeting of tumours, however, it was recently reported that antagonist tracers were superior to agonist tracers. The present study therefore evaluated various forms of the {sup 125}iodinated-Bolton-Hunter (BH)-exendin(9-39) antagonist tracer for the in vitro visualization of GLP-1 receptor-expressing tissues in rats and humans and compared it with the agonist tracer {sup 125}I-GLP-1(7-36)amide. Receptor autoradiography studies with {sup 125}I-GLP-1(7-36)amide agonist or {sup 125}I-BH-exendin(9-39) antagonist radioligands were performed in human and rat tissues. The antagonist {sup 125}I-BH-exendin(9-39) labelled at lysine 19 identifies all human and rat GLP-1 target tissues and GLP-1 receptor-expressing tumours. Binding is of high affinity and is comparable in all tested tissues in its binding properties with the agonist tracer {sup 125}I-GLP-1(7-36)amide. For comparison, {sup 125}I-BH-exendin(9-39) with the BH labelled at lysine 4 did identify the GLP-1 receptor in rat tissues but not in human tissues. The GLP-1 receptor antagonist exendin(9-39) labelled with {sup 125}I-BH at lysine 19 is an excellent GLP-1 radioligand that identifies human and rat GLP-1 receptors in normal and tumoural tissues. It may therefore be the molecular basis to develop suitable GLP-1 receptor antagonist radioligands for in vivo imaging of GLP-1 receptor-expressing tissues in patients. (orig.)

  5. Radiolabelled GLP-1 receptor antagonist binds to GLP-1 receptor-expressing human tissues

    International Nuclear Information System (INIS)

    Waser, Beatrice; Reubi, Jean Claude

    2014-01-01

    Radiolabelled glucagon-like peptide 1 (GLP-1) receptor agonists have recently been shown to successfully image benign insulinomas in patients. For the somatostatin receptor targeting of tumours, however, it was recently reported that antagonist tracers were superior to agonist tracers. The present study therefore evaluated various forms of the 125 iodinated-Bolton-Hunter (BH)-exendin(9-39) antagonist tracer for the in vitro visualization of GLP-1 receptor-expressing tissues in rats and humans and compared it with the agonist tracer 125 I-GLP-1(7-36)amide. Receptor autoradiography studies with 125 I-GLP-1(7-36)amide agonist or 125 I-BH-exendin(9-39) antagonist radioligands were performed in human and rat tissues. The antagonist 125 I-BH-exendin(9-39) labelled at lysine 19 identifies all human and rat GLP-1 target tissues and GLP-1 receptor-expressing tumours. Binding is of high affinity and is comparable in all tested tissues in its binding properties with the agonist tracer 125 I-GLP-1(7-36)amide. For comparison, 125 I-BH-exendin(9-39) with the BH labelled at lysine 4 did identify the GLP-1 receptor in rat tissues but not in human tissues. The GLP-1 receptor antagonist exendin(9-39) labelled with 125 I-BH at lysine 19 is an excellent GLP-1 radioligand that identifies human and rat GLP-1 receptors in normal and tumoural tissues. It may therefore be the molecular basis to develop suitable GLP-1 receptor antagonist radioligands for in vivo imaging of GLP-1 receptor-expressing tissues in patients. (orig.)

  6. A search for presynaptic inhibitory histamine receptors in guinea-pig tissues: Further H3 receptors but no evidence for H4 receptors.

    Science.gov (United States)

    Petri, Doris; Schlicker, Eberhard

    2016-07-01

    The histamine H4 receptor is coupled to Gi/o proteins and expressed on inflammatory cells and lymphoid tissues; it was suggested that this receptor also occurs in the brain or on peripheral neurones. Since many Gi/o protein-coupled receptors, including the H3 receptor, serve as presynaptic inhibitory receptors, we studied whether the sympathetic neurones supplying four peripheral tissues and the cholinergic neurones in the hippocampus from the guinea-pig are equipped with release-modulating H4 and H3 receptors. For this purpose, we preincubated tissue pieces from the aorta, atrium, renal cortex and vas deferens with (3)H-noradrenaline and hippocampal slices with (3)H-choline and determined the electrically evoked tritium overflow. The stimulation-evoked overflow in the five superfused tissues was inhibited by the muscarinic receptor agonist oxotremorine, which served as a positive control, but not affected by the H4 receptor agonist 4-methylhistamine. The H3 receptor agonist R-α-methylhistamine inhibited noradrenaline release in the peripheral tissues without affecting acetylcholine release in the hippocampal slices. Thioperamide shifted the concentration-response curve of histamine in the aorta and the renal cortex to the right, yielding apparent pA2 values of 8.0 and 8.1, respectively, which are close to its affinity at other H3 receptors but higher by one log unit than its pKi at the H4 receptor of the guinea-pig. In conclusion, histamine H4 receptors could not be identified in five experimental models of the guinea-pig that are suited for the detection of presynaptic inhibitory receptors whereas H3 receptors could be shown in the peripheral tissues but not in the hippocampus. This article is part of the Special Issue entitled 'Histamine Receptors'. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Role of a Ubiquitously Expressed Receptor in the Vertebrate Olfactory System

    OpenAIRE

    DeMaria, Shannon; Berke, Allison P.; Van Name, Eric; Heravian, Anisa; Ferreira, Todd; Ngai, John

    2013-01-01

    Odorant cues are recognized by receptors expressed on olfactory sensory neurons, the primary sensory neurons of the olfactory epithelium. Odorant receptors typically obey the “one receptor, one neuron” rule, in which the receptive field of the olfactory neuron is determined by the singular odorant receptor that it expresses. Odor-evoked receptor activity across the population of olfactory neurons is then interpreted by the brain to identify the molecular nature of the odorant stimulus. In the...

  8. Identifying Strategic Scientific Opportunities

    Science.gov (United States)

    As NCI's central scientific strategy office, CRS collaborates with the institute's divisions, offices, and centers to identify research opportunities to advance NCI's vision for the future of cancer research.

  9. Basolateral P2X receptors mediate inhibition of NaCl transport in mouse medullary thick ascending limb (mTAL)

    DEFF Research Database (Denmark)

    Marques, Rita D; de Bruijn, Pauline I.A.; Sørensen, Mads Vaarby

    2012-01-01

    Extracellular nucleotides regulate epithelial transport via luminal and basolateral P2 receptors. Renal epithelia express multiple P2 receptors, which mediate significant inhibition of solute absorption. Recently, we identified several P2 receptors in the medullary thick ascending limb (m...

  10. Identifying Breast Cancer Oncogenes

    Science.gov (United States)

    2011-10-01

    cells we observed that it promoted transformation of HMLE cells, suggesting a tumor suppressive role of Merlin in breast cancer (Figure 4B). A...08-1-0767 TITLE: Identifying Breast Cancer Oncogenes PRINCIPAL INVESTIGATOR: Yashaswi Shrestha...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 W81XWH-08-1-0767 Identifying Breast Cancer Oncogenes Yashaswi Shrestha Dana-Farber

  11. Radiosequence analysis of the human progestin receptor charged with [3H]promegestone. A comparison with the glucocorticoid receptor

    International Nuclear Information System (INIS)

    Stroemstedt, P.E.B.; Berkenstam, A.; Joernvall, H.G.; Gustafsson, J.A.; Carlstedt-Duke, J.

    1990-01-01

    Partially purified preparations of the human progestin receptor and the human and rat glucocorticoid receptor proteins were covalently charged with the synthetic progestin, [ 3 H]promegestone, by photoaffinity labeling. After labeling, the denaturated protein was cleaved and the mixture of peptides subjected to radiosequence analysis as previously described for the rat glucocorticoid receptor protein. The radioactivity labels identified, corresponded to Met-759 and Met-909 after photoaffinity labeling of the human progestin receptor, and Met-622 and Cys-754 after labeling of the rat glucocorticoid receptor. The residues labeled in the glucocorticoid receptor are the same as those previously reported to bind triamcinolone actonide. The corresponding residues were also labeled in the human glucocorticoid receptor. Met-759 of the progestin receptor and Met-622 of the rat glucocorticoid receptor are positioned within a segment with an overall high degree of sequence similarity and are equivalent. However, Met-909 (progestin receptor) and Cys-754 (glucocorticoid receptor) do not occur within equivalent segments of the two proteins. Thus, although the two classes of steroid hormone share a common structure within the A-ring, there are subtle differences in their interaction with the two separate receptor proteins

  12. GABA receptor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Doo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2007-04-15

    GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, GABA{sub A}-receptor that allows chloride to pass through a ligand gated ion channel and GABA{sub B}-receptor that uses G-proteins for signaling. The GABA{sub A}-receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate GABA{sub A}-receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with {sup 11}C-FMZ, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, {sup 18}F-fluoroflumazenil (FFMZ) has been developed to overcome {sup 11}C's short half-life. {sup 18}F-FFMZ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using '1{sup 1}C-FMZ PET instead of {sup 18}F-FDG, PET, restrict the foci better and may also help find lesions better than high resolution MR. GABA{sub A} receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, GABA imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas.

  13. GABA receptor imaging

    International Nuclear Information System (INIS)

    Lee, Jong Doo

    2007-01-01

    GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, GABA A -receptor that allows chloride to pass through a ligand gated ion channel and GABA B -receptor that uses G-proteins for signaling. The GABA A -receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate GABA A -receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with 11 C-FMZ, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, 18 F-fluoroflumazenil (FFMZ) has been developed to overcome 11 C's short half-life. 18 F-FFMZ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using '1 1 C-FMZ PET instead of 18 F-FDG, PET, restrict the foci better and may also help find lesions better than high resolution MR. GABA A receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, GABA imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas

  14. Tumor Suppressor Activity of the EphB2 Receptor in Prostate Cancer

    National Research Council Canada - National Science Library

    Pasquale, Elena B

    2007-01-01

    Mutations have been recently identified in the EphB2 receptor gene in prostate cancer suggesting that EphB2, a member of the large Eph receptor tyrosine kinase family, is a tumor suppressor in prostate cancer...

  15. Tumor Suppressor Activity of the EphB2 Receptor in Prostate Cancer

    National Research Council Canada - National Science Library

    Pasquale, Elena B

    2006-01-01

    Mutations have been recently identified in the EphB2 receptor gene in prostate cancer suggesting that EphB2, a member of the large Eph receptor tyrosine kinase family, is a tumor suppressor in prostate cancer...

  16. Key region of laminin receptor 1 for interaction with human period 1

    African Journals Online (AJOL)

    GREGORY

    2010-09-20

    Sep 20, 2010 ... acids) through yeast two-hybrid system in the present study. And we identified the ... the cell surface and functions as a membrane receptor for the adhesive ..... Circadian modulation of dopamine receptor responsiveness in ...

  17. Identifying Knowledge and Communication

    Directory of Open Access Journals (Sweden)

    Eduardo Coutinho Lourenço de Lima

    2006-12-01

    Full Text Available In this paper, I discuss how the principle of identifying knowledge which Strawson advances in ‘Singular Terms and Predication’ (1961, and in ‘Identifying Reference and Truth-Values’ (1964 turns out to constrain communication. The principle states that a speaker’s use of a referring expression should invoke identifying knowledge on the part of the hearer, if the hearer is to understand what the speaker is saying, and also that, in so referring, speakers are attentive to hearers’ epistemic states. In contrasting it with Russell’s Principle (Evans 1982, as well as with the principle of identifying descriptions (Donnellan 1970, I try to show that the principle of identifying knowledge, ultimately a condition for understanding, makes sense only in a situation of conversation. This allows me to conclude that the cooperative feature of communication (Grice 1975 and reference (Clark andWilkes-Gibbs 1986 holds also at the understanding level. Finally, I discuss where Strawson’s views seem to be unsatisfactory, and suggest how they might be improved.

  18. [Ceruloplasmin receptor on human erythrocytes].

    Science.gov (United States)

    Saenko, E L; Basevich, V V; Iaropolov, A I

    1988-08-01

    The structural fragments of the human ceruloplasmin (CP) molecule and of erythrocyte receptors which provide for the specific interaction of CP with erythrocytes were identified, and their properties were investigated. The interaction of CP with erythrocytes, both intact and treated with neuroaminidase and proteolytic enzymes (trypsin, chymotrypsin, papaine, pronase E) is described. Experiments with CP reception were performed at 4 degrees C, using [125I]CP and [125I]asialo-CP. The parameters of binding were determined in Scatchard plots. It was demonstrated that the specific binding of CP to erythrocyte receptors is determined by its interaction with two structural sites of the carbohydrate moiety of the CP molecule, i.e., the terminal residues of sialic acids and a site, (formula; see text) located at a large distance from the chain terminus.

  19. Characterization of the radioactive metabolites of the 5-HT1A receptor radioligand, [O-methyl-C-11]WAY-100635, in monkey and human plasma by HPLC : Comparison of the behaviour of an identified radioactive metabolite with parent radioligand in monkey using PET

    NARCIS (Netherlands)

    Osman, S; Lundkvist, C; Pike, VW; Halldin, C; McCarron, JA; Swahn, CG; Ginovart, N; Luthra, SK; Bench, CJ; Grasby, PM; Wikstrom, H; Barf, T; Cliffe, IA; Fletcher, A; Farde, L

    N-(2-(4-(2-Methoxy-phenyl)-1-piperazin-1-yl)ethyl)-N-(2-pyridyl)cyclohexanecarboxamide (WAY-100635), labelled in the O-methyl group with carbon-11 (t(1/2) = 20.4 min), is a promising radioligand for application with positron emission tomography (PET) to the study of 5-HT1A receptors in living human

  20. Glucocorticoid receptor modulators.

    Science.gov (United States)

    Meijer, Onno C; Koorneef, Lisa L; Kroon, Jan

    2018-06-01

    The glucocorticoid hormone cortisol acts throughout the body to support circadian processes and adaptation to stress. The glucocorticoid receptor is the target of cortisol and of synthetic glucocorticoids, which are used widely in the clinic. Both agonism and antagonism of the glucocorticoid receptor may be beneficial in disease, but given the wide expression of the receptor and involvement in various processes, beneficial effects are often accompanied by unwanted side effects. Selective glucocorticoid receptor modulators are ligands that induce a receptor conformation that allows activation of only a subset of downstream signaling pathways. Such molecules thereby combine agonistic and antagonistic properties. Here we discuss the mechanisms underlying selective receptor modulation and their promise in treating diseases in several organ systems where cortisol signaling plays a role. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  1. G protein-coupled receptor mutations and human genetic disease.

    Science.gov (United States)

    Thompson, Miles D; Hendy, Geoffrey N; Percy, Maire E; Bichet, Daniel G; Cole, David E C

    2014-01-01

    Genetic variations in G protein-coupled receptor genes (GPCRs) disrupt GPCR function in a wide variety of human genetic diseases. In vitro strategies and animal models have been used to identify the molecular pathologies underlying naturally occurring GPCR mutations. Inactive, overactive, or constitutively active receptors have been identified that result in pathology. These receptor variants may alter ligand binding, G protein coupling, receptor desensitization and receptor recycling. Receptor systems discussed include rhodopsin, thyrotropin, parathyroid hormone, melanocortin, follicle-stimulating hormone (FSH), luteinizing hormone, gonadotropin-releasing hormone (GNRHR), adrenocorticotropic hormone, vasopressin, endothelin-β, purinergic, and the G protein associated with asthma (GPRA or neuropeptide S receptor 1 (NPSR1)). The role of activating and inactivating calcium-sensing receptor (CaSR) mutations is discussed in detail with respect to familial hypocalciuric hypercalcemia (FHH) and autosomal dominant hypocalemia (ADH). The CASR mutations have been associated with epilepsy. Diseases caused by the genetic disruption of GPCR functions are discussed in the context of their potential to be selectively targeted by drugs that rescue altered receptors. Examples of drugs developed as a result of targeting GPCRs mutated in disease include: calcimimetics and calcilytics, therapeutics targeting melanocortin receptors in obesity, interventions that alter GNRHR loss from the cell surface in idiopathic hypogonadotropic hypogonadism and novel drugs that might rescue the P2RY12 receptor congenital bleeding phenotype. De-orphanization projects have identified novel disease-associated receptors, such as NPSR1 and GPR35. The identification of variants in these receptors provides genetic reagents useful in drug screens. Discussion of the variety of GPCRs that are disrupted in monogenic Mendelian disorders provides the basis for examining the significance of common

  2. C-Type Lectin Receptors in Asthma

    Directory of Open Access Journals (Sweden)

    Sabelo Hadebe

    2018-04-01

    Full Text Available Asthma is a heterogeneous disease that affects approximately 300 million people worldwide, largely in developed countries. The etiology of the disease is poorly understood, but is likely to involve specific innate and adaptive responses to inhaled microbial components that are found in allergens. Fungal-derived allergens represent a major contributing factor in the initiation, persistence, exacerbation, and severity of allergic asthma. C-type lectin like receptors, such as dectin-1, dectin-2, DC-specific intercellular adhesion molecule 3-grabbing nonintegrin, and mannose receptor, recognize many fungal-derived allergens and other structurally similar allergens derived from house dust mites (HDM. In some cases, the fungal derived allergens have been structurally and functionally identified alongside their respective receptors in both humans and mice. In this review, we discuss recent understanding on how selected fungal and HDM derived allergens as well as their known or unknown receptors shape allergic airway diseases.

  3. Dengue virus receptor

    OpenAIRE

    Hidari, Kazuya I.P.J.; Suzuki, Takashi

    2011-01-01

    Dengue virus is an arthropod-borne virus transmitted by Aedes mosquitoes. Dengue virus causes fever and hemorrhagic disorders in humans and non-human primates. Direct interaction of the virus introduced by a mosquito bite with host receptor molecule(s) is crucial for virus propagation and the pathological progression of dengue diseases. Therefore, elucidation of the molecular mechanisms underlying the interaction between dengue virus and its receptor(s) in both humans and mosquitoes is essent...

  4. Identifying and Managing Risk.

    Science.gov (United States)

    Abraham, Janice M.

    1999-01-01

    The role of the college or university chief financial officer in institutional risk management is (1) to identify risk (physical, casualty, fiscal, business, reputational, workplace safety, legal liability, employment practices, general liability), (2) to develop a campus plan to reduce and control risk, (3) to transfer risk, and (4) to track and…

  5. TARM1 Is a Novel Leukocyte Receptor Complex-Encoded ITAM Receptor That Costimulates Proinflammatory Cytokine Secretion by Macrophages and Neutrophils

    DEFF Research Database (Denmark)

    Radjabova, Valeria; Mastroeni, Piero; Skjødt, Karsten

    2015-01-01

    We identified a novel, evolutionarily conserved receptor encoded within the human leukocyte receptor complex and syntenic region of mouse chromosome 7, named T cell-interacting, activating receptor on myeloid cells-1 (TARM1). The transmembrane region of TARM1 contained a conserved arginine residu...

  6. Toll-like receptors and NOD-like receptors in rheumatic diseases.

    LENUS (Irish Health Repository)

    McCormack, William J

    2012-02-01

    The past 10 years have seen the description of families of receptors that drive proinflammatory cytokine production in infection and tissue injury. Two major classes have been examined in the context of inflammatory joint disease--the Toll-like receptors (TLRs) and NOD-like receptors (NLRs). TLRs such as TLR2 and TLR4 are being implicated in the pathology of rheumatoid arthritis, ankylosing spondylitis, lyme arthritis and osteoarthritis. Nalp3 has been identified as a key NLR for IL-1beta production and has been shown to have a particular role in gout. These findings present new therapeutic opportunities, possibly allowing for the replacement of biologics with small molecule inhibitors.

  7. Internally readable identifying tag

    International Nuclear Information System (INIS)

    Jefferts, K.B.; Jefferts, E.R.

    1980-01-01

    A method of identifying non-metallic objects by means of X-ray equipment is described in detail. A small metal pin with a number of grooves cut in a pre-determined equi-spaced pattern is implanted into the non-metallic object and by decoding the groove patterns using X-ray equipment, the object is uniquely identified. A specific example of such an application is in studying the migratory habits of fish. The pin inserted into the snout of the fish is 0.010 inch in diameter, 0.040 inch in length with 8 possible positions for grooves if spaced 0.005 inch apart. With 6 of the groove positions available for data, the capacity is 2 6 or 64 combinations; clearly longer pins would increase the data capacity. This method of identification is a major advance over previous techniques which necessitated destruction of the fish in order to recover the identification tag. (UK)

  8. The repertoire of olfactory C family G protein-coupled receptors in zebrafish: candidate chemosensory receptors for amino acids

    Directory of Open Access Journals (Sweden)

    Ngai John

    2006-12-01

    Full Text Available Abstract Background Vertebrate odorant receptors comprise at least three types of G protein-coupled receptors (GPCRs: the OR, V1R, and V2R/V2R-like receptors, the latter group belonging to the C family of GPCRs. These receptor families are thought to receive chemosensory information from a wide spectrum of odorant and pheromonal cues that influence critical animal behaviors such as feeding, reproduction and other social interactions. Results Using genome database mining and other informatics approaches, we identified and characterized the repertoire of 54 intact "V2R-like" olfactory C family GPCRs in the zebrafish. Phylogenetic analysis – which also included a set of 34 C family GPCRs from fugu – places the fish olfactory receptors in three major groups, which are related to but clearly distinct from other C family GPCRs, including the calcium sensing receptor, metabotropic glutamate receptors, GABA-B receptor, T1R taste receptors, and the major group of V2R vomeronasal receptor families. Interestingly, an analysis of sequence conservation and selective pressure in the zebrafish receptors revealed the retention of a conserved sequence motif previously shown to be required for ligand binding in other amino acid receptors. Conclusion Based on our findings, we propose that the repertoire of zebrafish olfactory C family GPCRs has evolved to allow the detection and discrimination of a spectrum of amino acid and/or amino acid-based compounds, which are potent olfactory cues in fish. Furthermore, as the major groups of fish receptors and mammalian V2R receptors appear to have diverged significantly from a common ancestral gene(s, these receptors likely mediate chemosensation of different classes of chemical structures by their respective organisms.

  9. Identifying Breast Cancer Oncogenes

    Science.gov (United States)

    2010-10-01

    tyrosine kinases with an SH3, SH2 and catalytic domain, it lacks a native myristylation signal shared by most members of this class [14], [38]. The...therapeutics and consequently, improve clinical outcomes. We aim to identify novel drivers of breast oncogenesis. We hypothesize that a kinase gain-of...human mammary epithelial cells. A pBabe-Puro-Myr-Flag kinase open reading frame (ORF) library was screened in immortalized human mammary epithelial

  10. Rock disposal problems identified

    Energy Technology Data Exchange (ETDEWEB)

    Knox, R

    1978-06-01

    Mathematical models are the only way of examining the return of radioactivity from nuclear waste to the environment over long periods of time. Work in Britain has helped identify areas where more basic data is required, but initial results look very promising for final disposal of high level waste in hard rock repositories. A report by the National Radiological Protection Board of a recent study, is examined.

  11. The First Fifteen Years of Steroid Receptor Research in Zebrafish; Characterization and Functional Analysis of the Receptors

    Directory of Open Access Journals (Sweden)

    Marcel J. M. Schaaf

    2017-07-01

    Full Text Available Steroid hormones regulate a wide range of processes in our body, and their effects are mediated by steroid receptors. In addition to their physiological role, these receptors mediate the effects of endocrine disrupting chemicals (EDCs and are widely used targets for dugs involved in the treatment of numerous diseases, ranging from cancer to inflammatory disorders. Over the last fifteen years, the zebrafish has increasingly been used as an animal model in steroid receptor research. Orthologues of all human steroid receptor genes appear to be present in zebrafish. All zebrafish steroid receptors have been characterized in detail, and their expression patterns have been analyzed. Functional studies have been performed using morpholino knockdown of receptor expression and zebrafish lines carrying mutations in one of their steroid receptor genes. To investigate the activity of the receptors in vivo, specific zebrafish reporter lines have been developed, and transcriptomic studies have been carried out to identify biomarkers for steroid receptor action. In this review, an overview of research on steroid receptors in zebrafish is presented, and it is concluded that further exploitation of the possibilities of the zebrafish model system will contribute significantly to the advancement of steroid receptor research in the next decade.

  12. Identification of Human P2X1 Receptor-interacting Proteins Reveals a Role of the Cytoskeleton in Receptor Regulation*

    Science.gov (United States)

    Lalo, Ulyana; Roberts, Jonathan A.; Evans, Richard J.

    2011-01-01

    P2X1 receptors are ATP-gated ion channels expressed by smooth muscle and blood cells. Carboxyl-terminally His-FLAG-tagged human P2X1 receptors were stably expressed in HEK293 cells and co-purified with cytoskeletal proteins including actin. Disruption of the actin cytoskeleton with cytochalasin D inhibited P2X1 receptor currents with no effect on the time course of the response or surface expression of the receptor. Stabilization of the cytoskeleton with jasplakinolide had no effect on P2X1 receptor currents but decreased receptor mobility. P2X2 receptor currents were unaffected by cytochalasin, and P2X1/2 receptor chimeras were used to identify the molecular basis of actin sensitivity. These studies showed that the intracellular amino terminus accounts for the inhibitory effects of cytoskeletal disruption similar to that shown for lipid raft/cholesterol sensitivity. Stabilization of the cytoskeleton with jasplakinolide abolished the inhibitory effects of cholesterol depletion on P2X1 receptor currents, suggesting that lipid rafts may regulate the receptor through stabilization of the cytoskeleton. These studies show that the cytoskeleton plays an important role in P2X1 receptor regulation. PMID:21757694

  13. Angiotensin type 2 receptors

    DEFF Research Database (Denmark)

    Sumners, Colin; de Kloet, Annette D; Krause, Eric G

    2015-01-01

    In most situations, the angiotensin AT2-receptor (AT2R) mediates physiological actions opposing those mediated by the AT1-receptor (AT1R), including a vasorelaxant effect. Nevertheless, experimental evidence vastly supports that systemic application of AT2R-agonists is blood pressure neutral...

  14. Molecular identification of the insect adipokinetic hormone receptors

    DEFF Research Database (Denmark)

    Staubli, Frank; Jørgensen, Thomas J D; Cazzamali, Giuseppe

    2002-01-01

    identified the first insect AKH receptors, namely those from the fruitfly Drosophila melanogaster and the silkworm Bombyx mori. These results represent a breakthrough for insect molecular endocrinology, because it will lead to the cloning of all AKH receptors from all model insects used in AKH research, and...

  15. NGA/Insulin receptor scanning

    International Nuclear Information System (INIS)

    Kurtaran, A.; Virgolini, I.

    1994-01-01

    Tc-99m-galactosyl-neoglycoalbumin (NGA) is one of the first receptor-based radiopharmaceuticals which specifically recognizes the hepatic binding protein (HBP) located on the surface of the hepatocytes. The exclusive interactin of NGA with HBP provided the basis for a kinetic model for the evaluation hepatocellular function. During the last years we have used NGA in more than 300 patients with various liver diseases including liver cirrhosis (Stages Child A to Child C), viral hepatitis, and carcinomas. In these studies, the calculated HBP densities, after i.v.-injection of Tc-99m-NGA, significantly correlated with the clinical course of the diseases. Furthermore, similar to conventional Tc-colloid, NGA provided excellent demonstration of 'cold spots' for hepatic masses. In a further approach we used another hepatocyte receptor-seeking radioligand, I-123-Tyr-A14- insulin, and found, that its in vitro-binding to hepatocellular carcinomas is greatly enhanced over normal hepatic tissue. On this basis, we developed a double-tracer method using NGA and insulin in a single study. Thus, areas of 'cold spots' identifying hepatic masses on NGA scans, take up I-123-Tyr-A14-insulin immediately after i.v.-injection. This was true for hepatocellular hepatomas, but not for adenocarcinomas. In conclusion, NGA/insulin receptor scanning could be a novel and save method for the demonstration of hepatocellular hepatomas. (author)

  16. NGA/Insulin receptor scanning

    Energy Technology Data Exchange (ETDEWEB)

    Kurtaran, A; Virgolini, I [Vienna Univ. (Austria). Abt. fuer Nuklearmedizin; Angelberger, P [Ludwig Boltzmann-Institut fuer Nuklearmedizin, Vienna (Austria)

    1994-10-01

    Tc-99m-galactosyl-neoglycoalbumin (NGA) is one of the first receptor-based radiopharmaceuticals which specifically recognizes the hepatic binding protein (HBP) located on the surface of the hepatocytes. The exclusive interactin of NGA with HBP provided the basis for a kinetic model for the evaluation hepatocellular function. During the last years we have used NGA in more than 300 patients with various liver diseases including liver cirrhosis (Stages Child A to Child C), viral hepatitis, and carcinomas. In these studies, the calculated HBP densities, after i.v.-injection of Tc-99m-NGA, significantly correlated with the clinical course of the diseases. Furthermore, similar to conventional Tc-colloid, NGA provided excellent demonstration of `cold spots` for hepatic masses. In a further approach we used another hepatocyte receptor-seeking radioligand, I-123-Tyr-A14- insulin, and found, that its in vitro-binding to hepatocellular carcinomas is greatly enhanced over normal hepatic tissue. On this basis, we developed a double-tracer method using NGA and insulin in a single study. Thus, areas of `cold spots` identifying hepatic masses on NGA scans, take up I-123-Tyr-A14-insulin immediately after i.v.-injection. This was true for hepatocellular hepatomas, but not for adenocarcinomas. In conclusion, NGA/insulin receptor scanning could be a novel and save method for the demonstration of hepatocellular hepatomas. (author).

  17. Lymphocyte receptors for pertussis toxin

    Energy Technology Data Exchange (ETDEWEB)

    Clark, C.G.; Armstrong, G.D. (Univ. of Alberta, Edmonton (Canada))

    1990-12-01

    We have investigated human T-lymphocyte receptors for pertussis toxin by affinity isolation and photoaffinity labeling procedures. T lymphocytes were obtained from peripheral human blood, surface iodinated, and solubilized in Triton X-100. The iodinated mixture was then passed through pertussis toxin-agarose, and the fractions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Autoradiography of the fixed, dried gels revealed several bands in the pertussis toxin-bound fraction that were not observed in fractions obtained from histone or fetuin-agarose. Further investigations employed a photoaffinity labeling reagent, sulfosuccinimidyl 2-(p-azido-salicylamido)-1,3'-dithiopropionate, to identify pertussis toxin receptors in freshly isolated peripheral blood monocytic cells, T lymphocytes, and Jurkat cells. In all three cell systems, the pertussis toxin affinity probe specifically labeled a single protein species with an apparent molecular weight of 70,000 that was not observed when the procedure was performed in the presence of excess unmodified pertussis toxin. A protein comparable in molecular weight to the one detected by the photoaffinity labeling technique was also observed among the species that bound to pertussis toxin-agarose. The results suggest that pertussis toxin may bind to a 70,000-Da receptor in human T lymphocytes.

  18. Glutamate receptor agonists

    DEFF Research Database (Denmark)

    Vogensen, Stine Byskov; Greenwood, Jeremy R; Bunch, Lennart

    2011-01-01

    The neurotransmitter (S)-glutamate [(S)-Glu] is responsible for most of the excitatory neurotransmission in the central nervous system. The effect of (S)-Glu is mediated by both ionotropic and metabotropic receptors. Glutamate receptor agonists are generally a-amino acids with one or more...... stereogenic centers due to strict requirements in the agonist binding pocket of the activated state of the receptor. By contrast, there are many examples of achiral competitive antagonists. The present review addresses how stereochemistry affects the activity of glutamate receptor ligands. The review focuses...... mainly on agonists and discusses stereochemical and conformational considerations as well as biostructural knowledge of the agonist binding pockets, which is useful in the design of glutamate receptor agonists. Examples are chosen to demonstrate how stereochemistry not only determines how the agonist...

  19. AMPA receptor ligands

    DEFF Research Database (Denmark)

    Strømgaard, Kristian; Mellor, Ian

    2004-01-01

    Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors (AMPAR), subtype of the ionotropic glutamate receptors (IGRs), mediate fast synaptic transmission in the central nervous system (CNS), and are involved in many neurological disorders, as well as being a key player in the f......Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors (AMPAR), subtype of the ionotropic glutamate receptors (IGRs), mediate fast synaptic transmission in the central nervous system (CNS), and are involved in many neurological disorders, as well as being a key player...... in the formation of memory. Hence, ligands affecting AMPARs are highly important for the study of the structure and function of this receptor, and in this regard polyamine-based ligands, particularly polyamine toxins, are unique as they selectively block Ca2+ -permeable AMPARs. Indeed, endogenous intracellular...

  20. Identifying phenomenal consciousness.

    Science.gov (United States)

    Schier, Elizabeth

    2009-03-01

    This paper examines the possibility of finding evidence that phenomenal consciousness is independent of access. The suggestion reviewed is that we should look for isomorphisms between phenomenal and neural activation spaces. It is argued that the fact that phenomenal spaces are mapped via verbal report is no problem for this methodology. The fact that activation and phenomenal space are mapped via different means does not mean that they cannot be identified. The paper finishes by examining how data addressing this theoretical question could be obtained.

  1. Lipophorin Receptor: The Insect Lipoprotein Receptor

    Indian Academy of Sciences (India)

    IAS Admin

    Director of ... function of the Lp is to deliver lipids throughout the insect body for metabolism ... Lipid is used as a major energy source for development as well as other metabolic .... LpR4 receptor variant was expressed exclusively in the brain and.

  2. Promiscuous Seven Transmembrane Receptors Sensing L-α-amino Acids

    DEFF Research Database (Denmark)

    Smajilovic, Sanela; Wellendorph, Petrine; Bräuner-Osborne, Hans

    2014-01-01

    A number of nutrient sensing seven trans-membrane (7TM) receptors have been identified and characterized over the past few years. While the sensing mechanisms to carbohydrates and free fatty acids are well understood, the molecular basis of amino acid sensing has recently come to the limelight....... The present review describes the current status of promiscuous L-α-amino acid sensors, the calcium sensing receptor (CaSR), the GPRC6A receptor, the T1R1/T1R3 receptor and also their molecular pharmacology, expression pattern and physiological significance....

  3. List identifies threatened ecosystems

    Science.gov (United States)

    Showstack, Randy

    2012-09-01

    The International Union for Conservation of Nature (IUCN) announced on 9 September that it will develop a new Red List of Ecosystems that will identify which ecosystems are vulnerable or endangered. The list, which is modeled on the group's Red List of Threatened Species™, could help to guide conservation activities and influence policy processes such as the Convention on Biological Diversity, according to the group. “We will assess the status of marine, terrestrial, freshwater, and subterranean ecosystems at local, regional, and global levels,” stated Jon Paul Rodriguez, leader of IUCN's Ecosystems Red List Thematic Group. “The assessment can then form the basis for concerted implementation action so that we can manage them sustainably if their risk of collapse is low or restore them if they are threatened and then monitor their recovery.”

  4. Global Microbial Identifier

    DEFF Research Database (Denmark)

    Wielinga, Peter; Hendriksen, Rene S.; Aarestrup, Frank Møller

    2017-01-01

    ) will likely also enable a much better understanding of the pathogenesis of the infection and the molecular basis of the host response to infection. But the full potential of these advances will only transpire if the data in this area become transferable and thereby comparable, preferably in open-source...... of microorganisms, for the identification of relevant genes and for the comparison of genomes to detect outbreaks and emerging pathogens. To harness the full potential of WGS, a shared global database of genomes linked to relevant metadata and the necessary software tools needs to be generated, hence the global...... microbial identifier (GMI) initiative. This tool will ideally be used in amongst others in the diagnosis of infectious diseases in humans and animals, in the identification of microorganisms in food and environment, and to track and trace microbial agents in all arenas globally. This will require...

  5. Transcriptional peroxisome proliferator-activated receptor γ ...

    African Journals Online (AJOL)

    user

    regulates slow fiber type formation during the transformation of muscle fiber type in S. prenanti. Key words: PGC-1ɑ, ... a master regulator of energy metabolism. PGC-1ɑ is identified ..... which is involved in hormone receptor families, such as ...

  6. Erythropoietin receptor signaling is membrane raft dependent

    NARCIS (Netherlands)

    K.L. McGraw (Kathy); G.M. Fuhler (Gwenny); J.O. Johnson (Joseph); J.A. Clark (Justine); G.C. Caceres (Gisela); L. Sokol (Lubomir); A.F. List (Alan)

    2012-01-01

    textabstractUpon erythropoietin (Epo) engagement, Epo-receptor (R) homodimerizes to activate JAK2 and Lyn, which phosphorylate STAT5. Although recent investigations have identified key negative regulators of Epo-R signaling, little is known about the role of membrane localization in controlling

  7. Exploiting intrinsic fluctuations to identify model parameters.

    Science.gov (United States)

    Zimmer, Christoph; Sahle, Sven; Pahle, Jürgen

    2015-04-01

    Parameterisation of kinetic models plays a central role in computational systems biology. Besides the lack of experimental data of high enough quality, some of the biggest challenges here are identification issues. Model parameters can be structurally non-identifiable because of functional relationships. Noise in measured data is usually considered to be a nuisance for parameter estimation. However, it turns out that intrinsic fluctuations in particle numbers can make parameters identifiable that were previously non-identifiable. The authors present a method to identify model parameters that are structurally non-identifiable in a deterministic framework. The method takes time course recordings of biochemical systems in steady state or transient state as input. Often a functional relationship between parameters presents itself by a one-dimensional manifold in parameter space containing parameter sets of optimal goodness. Although the system's behaviour cannot be distinguished on this manifold in a deterministic framework it might be distinguishable in a stochastic modelling framework. Their method exploits this by using an objective function that includes a measure for fluctuations in particle numbers. They show on three example models, immigration-death, gene expression and Epo-EpoReceptor interaction, that this resolves the non-identifiability even in the case of measurement noise with known amplitude. The method is applied to partially observed recordings of biochemical systems with measurement noise. It is simple to implement and it is usually very fast to compute. This optimisation can be realised in a classical or Bayesian fashion.

  8. Moth sex pheromone receptors and deceitful parapheromones.

    Directory of Open Access Journals (Sweden)

    Pingxi Xu

    Full Text Available The insect's olfactory system is so selective that male moths, for example, can discriminate female-produced sex pheromones from compounds with minimal structural modifications. Yet, there is an exception for this "lock-and-key" tight selectivity. Formate analogs can be used as replacement for less chemically stable, long-chain aldehyde pheromones, because male moths respond physiologically and behaviorally to these parapheromones. However, it remained hitherto unknown how formate analogs interact with aldehyde-sensitive odorant receptors (ORs. Neuronal responses to semiochemicals were investigated with single sensillum recordings. Odorant receptors (ORs were cloned using degenerate primers, and tested with the Xenopus oocyte expression system. Quality, relative quantity, and purity of samples were evaluated by gas chromatography and gas chromatography-mass spectrometry. We identified olfactory receptor neurons (ORNs housed in trichoid sensilla on the antennae of male navel orangeworm that responded equally to the main constituent of the sex pheromone, (11Z,13Z-hexadecadienal (Z11Z13-16Ald, and its formate analog, (9Z,11Z-tetradecen-1-yl formate (Z9Z11-14OFor. We cloned an odorant receptor co-receptor (Orco and aldehyde-sensitive ORs from the navel orangeworm, one of which (AtraOR1 was expressed specifically in male antennae. AtraOR1•AtraOrco-expressing oocytes responded mainly to Z11Z13-16Ald, with moderate sensitivity to another component of the sex pheromone, (11Z,13Z-hexadecadien-1-ol. Surprisingly, this receptor was more sensitive to the related formate than to the natural sex pheromone. A pheromone receptor from Heliothis virescens, HR13 ( = HvirOR13 showed a similar profile, with stronger responses elicited by a formate analog than to the natural sex pheromone, (11Z-hexadecenal thus suggesting this might be a common feature of moth pheromone receptors.

  9. Expression and function of nicotinic acetylcholine receptors in stem cells

    Directory of Open Access Journals (Sweden)

    Herman S. Cheung

    2016-07-01

    Full Text Available Nicotinic acetylcholine receptors are prototypical ligand gated ion channels typically found in muscular and neuronal tissues. Functional nicotinic acetylcholine receptors, however, have also recently been identified on other cell types, including stem cells. Activation of these receptors by the binding of agonists like choline, acetylcholine, or nicotine has been implicated in many cellular changes. In regards to stem cell function, nicotinic acetylcholine receptor activation leads to changes in stem cell proliferation, migration and differentiation potential. In this review we summarize the expression and function of known nicotinic acetylcholine receptors in different classes of stem cells including: pluripotent stem cells, mesenchymal stem cells, periodontal ligament derived stem cells, and neural progenitor cells and discuss the potential downstream effects of receptor activation on stem cell function.

  10. Posttranslational Modification Biology of Glutamate Receptors and Drug Addiction

    Directory of Open Access Journals (Sweden)

    Li-Min eMao

    2011-03-01

    Full Text Available Posttranslational covalent modifications of glutamate receptors remain a hot topic. Early studies have established that this family of receptors, including almost all ionotropic and metabotropic glutamate receptor subtypes, undergoes active phosphorylation at serine, threonine, or tyrosine residues on their intracellular domains. Recent evidence identifies several glutamate receptor subtypes to be direct substrates for palmitoylation at cysteine residues. Other modifications such as ubiquitination and sumoylation at lysine residues also occur to certain glutamate receptors. These modifications are dynamic and reversible in nature and are regulatable by changing synaptic inputs. The regulated modifications significantly impact the receptor in many ways, including interrelated changes in biochemistry (synthesis, subunit assembling and protein-protein interactions, subcellular redistribution (trafficking, endocytosis, synaptic delivery and clustering, and physiology, usually associated with changes in synaptic plasticity. Glutamate receptors are enriched in the striatum and cooperate closely with dopamine to regulate striatal signaling. Emerging evidence shows that modification processes of striatal glutamate receptors are sensitive to addictive drugs, such as psychostimulants (cocaine and amphetamines. Altered modifications are believed to be directly linked to enduring receptor/synaptic plasticity and drug-seeking. This review summarizes several major types of modifications of glutamate receptors and analyzes the role of these modifications in striatal signaling and in the pathogenesis of psychostimulant addiction.

  11. Adenosine Receptor Heteromers and their Integrative Role in Striatal Function

    Directory of Open Access Journals (Sweden)

    Sergi Ferré

    2007-01-01

    Full Text Available By analyzing the functional role of adenosine receptor heteromers, we review a series of new concepts that should modify our classical views of neurotransmission in the central nervous system (CNS. Neurotransmitter receptors cannot be considered as single functional units anymore. Heteromerization of neurotransmitter receptors confers functional entities that possess different biochemical characteristics with respect to the individual components of the heteromer. Some of these characteristics can be used as a “biochemical fingerprint” to identify neurotransmitter receptor heteromers in the CNS. This is exemplified by changes in binding characteristics that are dependent on coactivation of the receptor units of different adenosine receptor heteromers. Neurotransmitter receptor heteromers can act as “processors” of computations that modulate cell signaling, sometimes critically involved in the control of pre- and postsynaptic neurotransmission. For instance, the adenosine A1-A2A receptor heteromer acts as a concentration-dependent switch that controls striatal glutamatergic neurotransmission. Neurotransmitter receptor heteromers play a particularly important integrative role in the “local module” (the minimal portion of one or more neurons and/or one or more glial cells that operates as an independent integrative unit, where they act as processors mediating computations that convey information from diverse volume-transmitted signals. For instance, the adenosine A2A-dopamine D2 receptor heteromers work as integrators of two different neurotransmitters in the striatal spine module.

  12. Cutaneous corpuscular receptors of the human glans clitoris: descriptive characteristics and comparison with the glans penis.

    Science.gov (United States)

    Shih, Cheryl; Cold, Christopher J; Yang, Claire C

    2013-07-01

    The female genital sensory pathways that initiate sexual arousal reflexes begin with cutaneous corpuscular receptors in the glabrous genital skin, including those of the glans clitoris. The aim of this study is to characterize the corpuscular receptors of the glans clitoris. In addition, we compared basic features with the receptors of the glans penis. Number of stained receptors. Five cadaveric vulvectomy specimens and four cadaveric penile specimens were used. They were serially sectioned and stained with hematoxylin and eosin. Selected blocks were stained with Masson's trichrome, and immunohistochemical staining was done with neuronal markers S-100 and neurofilament. Using the three stains, we identified an abundance of corpuscular receptors within the glans clitoris, as compared with the surrounding prepuce. These receptors were of varied arrangements, situated in the subepithelial tissues of the glans clitoris. They were indistinguishable from the receptors of the glans penis. The number of receptors per 100× high-powered field ranged from 1 to 14, whereas the receptor density in the glans penis ranged from 1 to 3. A second type of receptor, the Pacinian corpuscle, was identified within the suspensory ligament along the trunks of the dorsal nerve but not within the glans itself. The glans clitoris is densely innervated with cutaneous corpuscular receptors, and these receptors are morphologically similar to the corpuscular receptors of the glans penis. The glans clitoris has greater variability in receptor density compared with the glans penis. © 2013 International Society for Sexual Medicine.

  13. Serotonin Receptors in Hippocampus

    Science.gov (United States)

    Berumen, Laura Cristina; Rodríguez, Angelina; Miledi, Ricardo; García-Alcocer, Guadalupe

    2012-01-01

    Serotonin is an ancient molecular signal and a recognized neurotransmitter brainwide distributed with particular presence in hippocampus. Almost all serotonin receptor subtypes are expressed in hippocampus, which implicates an intricate modulating system, considering that they can be localized as autosynaptic, presynaptic, and postsynaptic receptors, even colocalized within the same cell and being target of homo- and heterodimerization. Neurons and glia, including immune cells, integrate a functional network that uses several serotonin receptors to regulate their roles in this particular part of the limbic system. PMID:22629209

  14. Genomic organization, annotation, and ligand-receptor inferences of chicken chemokines and chemokine receptor genes based on comparative genomics

    Directory of Open Access Journals (Sweden)

    Sze Sing-Hoi

    2005-03-01

    Full Text Available Abstract Background Chemokines and their receptors play important roles in host defense, organogenesis, hematopoiesis, and neuronal communication. Forty-two chemokines and 19 cognate receptors have been found in the human genome. Prior to this report, only 11 chicken chemokines and 7 receptors had been reported. The objectives of this study were to systematically identify chicken chemokines and their cognate receptor genes in the chicken genome and to annotate these genes and ligand-receptor binding by a comparative genomics approach. Results Twenty-three chemokine and 14 chemokine receptor genes were identified in the chicken genome. All of the chicken chemokines contained a conserved CC, CXC, CX3C, or XC motif, whereas all the chemokine receptors had seven conserved transmembrane helices, four extracellular domains with a conserved cysteine, and a conserved DRYLAIV sequence in the second intracellular domain. The number of coding exons in these genes and the syntenies are highly conserved between human, mouse, and chicken although the amino acid sequence homologies are generally low between mammalian and chicken chemokines. Chicken genes were named with the systematic nomenclature used in humans and mice based on phylogeny, synteny, and sequence homology. Conclusion The independent nomenclature of chicken chemokines and chemokine receptors suggests that the chicken may have ligand-receptor pairings similar to mammals. All identified chicken chemokines and their cognate receptors were identified in the chicken genome except CCR9, whose ligand was not identified in this study. The organization of these genes suggests that there were a substantial number of these genes present before divergence between aves and mammals and more gene duplications of CC, CXC, CCR, and CXCR subfamilies in mammals than in aves after the divergence.

  15. Radiograph identifying means

    International Nuclear Information System (INIS)

    Sheldon, A.D.

    1983-01-01

    A flexible character-indentable plastics embossing tape is backed by and bonded to a lead strip, not more than 0.025 inches thick, to form a tape suitable for identifying radiographs. The lead strip is itself backed by a relatively thin and flimsy plastics or fabric strip which, when removed, allows the lead plastic tape to be pressure-bonded to the surface to be radiographed. A conventional tape-embossing gun is used to indent the desired characters in succession into the lead-backed tape, without necessarily severing the lead; and then the backing strip is peeled away to expose the layer of adhesive which pressure-bonds the indented tape to the object to be radiographed. X-rays incident on the embossed tape will cause the raised characters to show up dark on the subsequently-developed film, whilst the raised side areas will show up white. Each character will thus stand out on the developed film. (author)

  16. Molecular pharmacological phenotyping of EBI2. An orphan seven-transmembrane receptor with constitutive activity

    DEFF Research Database (Denmark)

    Rosenkilde, Mette M; Benned-Jensen, Tau; Holst, Peter J

    2006-01-01

    Epstein-Barr virus (EBV)-induced receptor 2 (EBI2) is an orphan seven-transmembrane (7TM) receptor originally identified as the most up-regulated gene (>200-fold) in EBV-infected cells. Here we show that EBI2 signals with constitutive activity through Galpha(i) as determined by a receptor...

  17. Intrapulmonary receptors in the Tegu lizard: I. Sensitivity to CO2.

    Science.gov (United States)

    Feede, M R; Kuhlmann, W D; Scheid, P

    1977-02-01

    Single unit vagal recordings from intrapulmonary receptors were obtained in decerebrate, paralyzed lizards both during pump ventilation and during unidirectional ventilation on the cannulated, sack-shaped lung. Two types of receptors were identified: (1) CO2-receptors, which increased their discharge frequency as intrapulmonary CO2 concentration decreased but were not sensitive to stretch of the lung. (2) Mechanoreceptors, which rapidly increased discharge frequency when the lung was stretched. These receptors' CO2 sensitivity varied. Lungs of lizards thus appeared to possess both CO2 receptors, which have functional characteristics similar to those in birds, and mechanoreceptors with properties similar to stretch receptors in mammals.

  18. Serotonin 2A receptor antagonists for treatment of schizophrenia

    DEFF Research Database (Denmark)

    Ebdrup, Bjørn Hylsebeck; Rasmussen, Hans; Arnt, Jørn

    2011-01-01

    Introduction: All approved antipsychotic drugs share an affinity for the dopamine 2 (D2) receptor; however, these drugs only partially ameliorate the symptoms of schizophrenia. It is, therefore, of paramount importance to identify new treatment strategies for schizophrenia. Areas covered......: Preclinical, clinical and post-mortem studies of the serotonin 5-HT2A system in schizophrenia are reviewed. The implications of a combined D2 and 5-HT2A receptor blockade, which is obtained by several current antipsychotic drugs, are discussed, and the rationale for the development of more selective 5-HT2A...... receptor antagonists is evaluated. Moreover, the investigational pipeline of major pharmaceutical companies is examined and an Internet search conducted to identify other pharmaceutical companies investigating 5-HT2A receptor antagonists for the treatment of schizophrenia. Expert opinion: 5-HT2A receptor...

  19. Nature and regulation of the receptors for insulin-like growth factors

    International Nuclear Information System (INIS)

    Rechler, M.M.; Nissley, S.P.

    1985-01-01

    Two subtypes of IGF receptors have been identified. Type I IGF receptors have a Mr greater than 300,000 and are composed of disulfide-linked 130,000-dalton (alpha) and approximately 90,000-dalton (beta) subunits. Type I receptors preferentially bind IGF-I but also bind IGF-II and, more weakly, insulin. Type II IGF receptors consist of a 250,000-dalton protein that contains internal disulfide bonds but is not linked to other membrane components. Type II receptors bind IGF-II with higher affinity than IGF-I. They do not interact with even very high concentrations of insulin. Type I IGF receptors and insulin receptors are homologous structures. Type II IGF receptors do not appear to be homologous to type I receptors. Type II receptors do not appear to be downregulated. Insulin acutely upregulates type II IGF receptors in intact rat adipose cells by effecting a redistribution of receptors cycling between a large intracellular pool and the plasma membrane. Insulin and the IGFs elicit the same biological responses, either by cross-reacting with one of the receptors for the heterologous ligand or by concurrent activation of convergent effector pathways by binding to the homologous receptor. Which mechanism is utilized appears to depend more on the tissue than on the biological response. Insulin desensitizes rat hepatoma cells to the actions of insulin and IGFs, mediated by both insulin and IGF receptors, by mechanisms distal to hormone binding and possibly common to IGF and insulin effector pathways

  20. Seven transmembrane G protein-coupled receptor repertoire of gastric ghrelin cells

    DEFF Research Database (Denmark)

    Engelstoft, Maja S; Park, Won-Mee; Sakata, Ichiro

    2013-01-01

    The molecular mechanisms regulating secretion of the orexigenic-glucoregulatory hormone ghrelin remain unclear. Based on qPCR analysis of FACS-purified gastric ghrelin cells, highly expressed and enriched 7TM receptors were comprehensively identified and functionally characterized using in vitro......, ex vivo and in vivo methods. Five Gαs-coupled receptors efficiently stimulated ghrelin secretion: as expected the β1-adrenergic, the GIP and the secretin receptors but surprisingly also the composite receptor for the sensory neuropeptide CGRP and the melanocortin 4 receptor. A number of Gαi....../o-coupled receptors inhibited ghrelin secretion including somatostatin receptors SSTR1, SSTR2 and SSTR3 and unexpectedly the highly enriched lactate receptor, GPR81. Three other metabolite receptors known to be both Gαi/o- and Gαq/11-coupled all inhibited ghrelin secretion through a pertussis toxin-sensitive Gαi...

  1. Anxiety and Depression: Mouse Genetics and Pharmacological Approaches to the Role of GABAA Receptor Subtypes

    Science.gov (United States)

    Smith, Kiersten S.; Rudolph, Uwe

    2012-01-01

    GABAA receptors mediate fast synaptic inhibitory neurotransmission throughout the central nervous system. Recent work indicates a role for GABAA receptors in physiologically modulating anxiety and depression levels. In this review, we summarize research that led to the identification of the essential role of GABAA receptors in counteracting trait anxiety and depression-related behaviors, and research aimed at identifying individual GABAA receptor subtypes involved in physiological and pharmacological modulation of emotions. PMID:21810433

  2. NR4A nuclear receptors are orphans but not lonesome.

    Science.gov (United States)

    Kurakula, Kondababu; Koenis, Duco S; van Tiel, Claudia M; de Vries, Carlie J M

    2014-11-01

    The NR4A subfamily of nuclear receptors consists of three mammalian members: Nur77, Nurr1, and NOR-1. The NR4A receptors are involved in essential physiological processes such as adaptive and innate immune cell differentiation, metabolism and brain function. They act as transcription factors that directly modulate gene expression, but can also form trans-repressive complexes with other transcription factors. In contrast to steroid hormone nuclear receptors such as the estrogen receptor or the glucocorticoid receptor, no ligands have been described for the NR4A receptors. This lack of known ligands might be explained by the structure of the ligand-binding domain of NR4A receptors, which shows an active conformation and a ligand-binding pocket that is filled with bulky amino acid side-chains. Other mechanisms, such as transcriptional control, post-translational modifications and protein-protein interactions therefore seem to be more important in regulating the activity of the NR4A receptors. For Nur77, over 80 interacting proteins (the interactome) have been identified so far, and roughly half of these interactions has been studied in more detail. Although the NR4As show some overlap in interacting proteins, less information is available on the interactome of Nurr1 and NOR-1. Therefore, the present review will describe the current knowledge on the interactomes of all three NR4A nuclear receptors with emphasis on Nur77. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Research progress of the bitter taste receptor genes in primates.

    Science.gov (United States)

    Feng, Ping; Luo, Rui-Jian

    2018-02-20

    Among the five basic tastes (umami, sweet, bitter, salty and sour), the perception of bitterness is believed to protect animals from digesting toxic and harmful substances, thus it is vital for animal survival. The taste of bitterness is triggered by the interaction between bitter substances and bitter taste receptors, which are encoded by Tas2rs. The gene numbers vary largely across species to meet different demands. So far, several ligands of bitter receptors have been identified in primates. They also discovered that the selective pressure of certain bitter taste receptor genes vary across taxa, genes or even different functional regions of the gene. In this review, we summarize the research progress of bitter taste receptor genes in primates by introducing the functional diversity of bitter receptors, the specific interaction between bitter taste receptors and ligands, the relationship between the evolutionary pattern of bitter taste receptors and diets, and the adaptive evolution of bitter taste receptor genes. We aim to provide a reference for further research on bitter receptor genes in primates.

  4. Erythropoietin Receptor Signaling Is Membrane Raft Dependent

    Science.gov (United States)

    McGraw, Kathy L.; Fuhler, Gwenny M.; Johnson, Joseph O.; Clark, Justine A.; Caceres, Gisela C.; Sokol, Lubomir; List, Alan F.

    2012-01-01

    Upon erythropoietin (Epo) engagement, Epo-receptor (R) homodimerizes to activate JAK2 and Lyn, which phosphorylate STAT5. Although recent investigations have identified key negative regulators of Epo-R signaling, little is known about the role of membrane localization in controlling receptor signal fidelity. Here we show a critical role for membrane raft (MR) microdomains in creation of discrete signaling platforms essential for Epo-R signaling. Treatment of UT7 cells with Epo induced MR assembly and coalescence. Confocal microscopy showed that raft aggregates significantly increased after Epo stimulation (mean, 4.3±1.4(SE) vs. 25.6±3.2 aggregates/cell; p≤0.001), accompanied by a >3-fold increase in cluster size (p≤0.001). Raft fraction immunoblotting showed Epo-R translocation to MR after Epo stimulation and was confirmed by fluorescence microscopy in Epo stimulated UT7 cells and primary erythroid bursts. Receptor recruitment into MR was accompanied by incorporation of JAK2, Lyn, and STAT5 and their activated forms. Raft disruption by cholesterol depletion extinguished Epo induced Jak2, STAT5, Akt and MAPK phosphorylation in UT7 cells and erythroid progenitors. Furthermore, inhibition of the Rho GTPases Rac1 or RhoA blocked receptor recruitment into raft fractions, indicating a role for these GTPases in receptor trafficking. These data establish a critical role for MR in recruitment and assembly of Epo-R and signal intermediates into discrete membrane signaling units. PMID:22509308

  5. Cellular receptors for human enterovirus species A

    Directory of Open Access Journals (Sweden)

    Yorihiro eNishimura

    2012-03-01

    Full Text Available Human enterovirus species A (HEV-A is one of the four species of HEV in the genus Enterovirus in the family Picornaviridae. Among HEV-A, coxsackievirus A16 (CVA16 and enterovirus 71 (EV71 are the major causative agents of hand, foot, and mouth disease (HFMD. Some other types of HEV-A are commonly associated with herpangina. Although HFMD and herpangina due to HEV-A are common febrile diseases among infants and children, EV71 can cause various neurological diseases, such as aseptic meningitis and fatal encephalitis.Recently, two human transmembrane proteins, P-selectin glycoprotein ligand-1 (PSGL-1 and scavenger receptor class B, member 2 (SCARB2, were identified as functional receptors for EV71 and CVA16. In in vitro infection experiments using the prototype HEV-A strains, PSGL-1 and SCARB2 could be responsible for the specific receptors for EV71 and CVA16. However, the involvement of both receptors in the in vitro and in vivo infections of clinical isolates of HEV-A has not been clarified yet. To elucidate a diverse array of the clinical outcome of HEV-A-associated diseases, the identification and characterization of HEV-A receptors may provide useful information in understanding the HEV-A pathogenesis at a molecular level.

  6. Ionotropic crustacean olfactory receptors.

    Directory of Open Access Journals (Sweden)

    Elizabeth A Corey

    Full Text Available The nature of the olfactory receptor in crustaceans, a major group of arthropods, has remained elusive. We report that spiny lobsters, Panulirus argus, express ionotropic receptors (IRs, the insect chemosensory variants of ionotropic glutamate receptors. Unlike insects IRs, which are expressed in a specific subset of olfactory cells, two lobster IR subunits are expressed in most, if not all, lobster olfactory receptor neurons (ORNs, as confirmed by antibody labeling and in situ hybridization. Ligand-specific ORN responses visualized by calcium imaging are consistent with a restricted expression pattern found for other potential subunits, suggesting that cell-specific expression of uncommon IR subunits determines the ligand sensitivity of individual cells. IRs are the only type of olfactory receptor that we have detected in spiny lobster olfactory tissue, suggesting that they likely mediate olfactory signaling. Given long-standing evidence for G protein-mediated signaling in activation of lobster ORNs, this finding raises the interesting specter that IRs act in concert with second messenger-mediated signaling.

  7. SPARQL-enabled identifier conversion with Identifiers.org

    Science.gov (United States)

    Wimalaratne, Sarala M.; Bolleman, Jerven; Juty, Nick; Katayama, Toshiaki; Dumontier, Michel; Redaschi, Nicole; Le Novère, Nicolas; Hermjakob, Henning; Laibe, Camille

    2015-01-01

    Motivation: On the semantic web, in life sciences in particular, data is often distributed via multiple resources. Each of these sources is likely to use their own International Resource Identifier for conceptually the same resource or database record. The lack of correspondence between identifiers introduces a barrier when executing federated SPARQL queries across life science data. Results: We introduce a novel SPARQL-based service to enable on-the-fly integration of life science data. This service uses the identifier patterns defined in the Identifiers.org Registry to generate a plurality of identifier variants, which can then be used to match source identifiers with target identifiers. We demonstrate the utility of this identifier integration approach by answering queries across major producers of life science Linked Data. Availability and implementation: The SPARQL-based identifier conversion service is available without restriction at http://identifiers.org/services/sparql. Contact: sarala@ebi.ac.uk PMID:25638809

  8. SPARQL-enabled identifier conversion with Identifiers.org.

    Science.gov (United States)

    Wimalaratne, Sarala M; Bolleman, Jerven; Juty, Nick; Katayama, Toshiaki; Dumontier, Michel; Redaschi, Nicole; Le Novère, Nicolas; Hermjakob, Henning; Laibe, Camille

    2015-06-01

    On the semantic web, in life sciences in particular, data is often distributed via multiple resources. Each of these sources is likely to use their own International Resource Identifier for conceptually the same resource or database record. The lack of correspondence between identifiers introduces a barrier when executing federated SPARQL queries across life science data. We introduce a novel SPARQL-based service to enable on-the-fly integration of life science data. This service uses the identifier patterns defined in the Identifiers.org Registry to generate a plurality of identifier variants, which can then be used to match source identifiers with target identifiers. We demonstrate the utility of this identifier integration approach by answering queries across major producers of life science Linked Data. The SPARQL-based identifier conversion service is available without restriction at http://identifiers.org/services/sparql. © The Author 2015. Published by Oxford University Press.

  9. Identification of Receptor Ligands and Receptor Subtypes Using Antagonists in a Capillary Electrophoresis Single-Cell Biosensor Separation System

    Science.gov (United States)

    Fishman, Harvey A.; Orwar, Owe; Scheller, Richard H.; Zare, Richard N.

    1995-08-01

    A capillary electrophoresis system with single-cell biosensors as a detector has been used to separate and identify ligands in complex biological samples. The power of this procedure was significantly increased by introducing antagonists that inhibited the cellular response from selected ligand-receptor interactions. The single-cell biosensor was based on the ligand-receptor binding and G-protein-mediated signal transduction pathways in PC12 and NG108-15 cell lines. Receptor activation was measured as increases in cytosolic free calcium ion concentration by using fluorescence microscopy with the intracellular calcium ion indicator fluo-3 acetoxymethyl ester. Specifically, a mixture of bradykinin (BK) and acetylcholine (ACh) was fractionated and the components were identified by inhibiting the cellular response with icatibant (HOE 140), a selective antagonist to the BK B_2 receptor subtype (B_2BK), and atropine, an antagonist to muscarinic ACh receptor subtypes. Structurally related forms of BK were also identified based on inhibiting B_2BK receptors. Applications of this technique include identification of endogenous BK in a lysate of human hepatocellular carcinoma cells (Hep G2) and screening for bioactivity of BK degradation products in human blood plasma. The data demonstrate that the use of antagonists with a single-cell biosensor separation system aids identification of separated components and receptor subtypes.

  10. Assays for calcitonin receptors

    International Nuclear Information System (INIS)

    Teitelbaum, A.P.; Nissenson, R.A.; Arnaud, C.D.

    1985-01-01

    The assays for calcitonin receptors described focus on their use in the study of the well-established target organs for calcitonin, bone and kidney. The radioligand used in virtually all calcitonin binding studies is 125 I-labelled salmon calcitonin. The lack of methionine residues in this peptide permits the use of chloramine-T for the iodination reaction. Binding assays are described for intact bone, skeletal plasma membranes, renal plasma membranes, and primary kidney cell cultures of rats. Studies on calcitonin metabolism in laboratory animals and regulation of calcitonin receptors are reviewed

  11. Identification of the receptor scavenging hemopexin-heme complexes

    DEFF Research Database (Denmark)

    Hvidberg, Vibeke; Maniecki, Maciej B; Jacobsen, Christian

    2005-01-01

    and is suggested to facilitate cellular heme metabolism. Using a ligand-affinity approach, we purified the human hemopexin-heme receptor and identified it as the low-density lipoprotein receptor-related protein (LRP)/CD91, a receptor expressed in several cell types including macrophages, hepatocytes, neurons......, and syncytiotrophoblasts. Binding experiments, including Biacore analysis, showed that hemopexin-heme complex formation elicits the high receptor affinity. Uptake studies of radio-labeled hemopexin-heme complex in LRP/CD91-expressing COS cells and confocal microscopy of the cellular processing of fluorescent hemopexin......-heme complexes are removed by a receptor-mediated pathway showing striking similarities to the CD163-mediated haptoglobin-hemoglobin clearance in macrophages. Furthermore, the data indicate a hitherto unknown role of LRP/CD91 in inflammation....

  12. Allosteric modulation of G-protein coupled receptors

    DEFF Research Database (Denmark)

    Jensen, Anders A.; Spalding, Tracy A

    2004-01-01

    are believed to activate (agonists) or inhibit (competitive antagonists) receptor signalling by binding the receptor at the same site as the endogenous agonist, the orthosteric site. In contrast, allosteric ligands modulate receptor function by binding to different regions in the receptor, allosteric sites....... In recent years, combinatorial chemistry and high throughput screening have helped identify several allosteric GPCR modulators with novel structures, several of which already have become valuable pharmacological tools and may be candidates for clinical testing in the near future. This mini review outlines...... the current status and perspectives of allosteric modulation of GPCR function with emphasis on the pharmacology of endogenous and synthesised modulators, their receptor interactions and the therapeutic prospects of allosteric ligands compared to orthosteric ligands....

  13. Steroid hormone and epidermal growth factor receptors in meningiomas.

    Science.gov (United States)

    Horsfall, D J; Goldsmith, K G; Ricciardelli, C; Skinner, J M; Tilley, W D; Marshall, V R

    1989-11-01

    A prospective study of steroid hormone and epidermal growth factor receptor expression in 57 meningiomas is presented. Scatchard analysis of radioligand binding identified 20% of meningiomas as expressing classical oestrogen receptors (ER) at levels below that normally accepted for positivity, the remainder being negative. ER could not be visualized in any meningioma using immunocytochemistry. Alternatively, 74% of meningiomas demonstrated the presence of progesterone receptors (PR) by Scatchard analysis, the specificity of which could not be attributed to glucocorticoid or androgen receptors. Confirmation of classical PR presence was determined by immunocytochemical staining. The presence of epidermal growth factor receptor (EGFR) was demonstrated in 100% of meningiomas using immunocytochemical staining. These data are reviewed in the context of previously reported results and are discussed in relation to the potential for medical therapy as an adjunct to surgery.

  14. Angiotensin type 2 receptor (AT2R) and receptor Mas

    DEFF Research Database (Denmark)

    Villela, Daniel; Leonhardt, Julia; Patel, Neal

    2015-01-01

    The angiotensin type 2 receptor (AT2R) and the receptor Mas are components of the protective arms of the renin-angiotensin system (RAS), i.e. they both mediate tissue protective and regenerative actions. The spectrum of actions of these two receptors and their signalling mechanisms display striki...

  15. Prostaglandins and their receptors in insect biology

    Directory of Open Access Journals (Sweden)

    David eStanley

    2011-12-01

    Full Text Available We treat the biological significance of prostaglandins (PGs and their known receptors in insect biology. PGs and related eicosanoids are oxygenated derivatives of arachidonic acid (AA and two other C20 polyunsaturated fatty acids. PGs are mostly appreciated in the context of biomedicine, but a growing body of literature indicates the biological significance of these compounds extends throughout the animal kingdom, and possibly beyond. PGs act in several crucial areas of insect biology. In reproduction, a specific PG, PGE2, releases oviposition behavior in most crickets and a few other insect species; PGs also mediate events in egg development in some species, which may represent all insects. PGs play major roles in modulating fluid secretion in Malpighian tubules, rectum and salivary glands, although, again, this has been studied in only a few insect species that may represent the Class. Insect immunity is a very complex defense system. PGs and other eicosanoids mediate a large number of immune reactions to infection and invasion. The actions of most PGs are mediated by specific receptors. Biomedical research has discovered a great deal of knowledge about PG receptors in mammals, including their structures, pharmacology, molecular biology and cellular locations. Studies of PG receptors in insects lag behind the biomedical background, however, recent results hold the promise of accelerated research in this area. A PG receptor has been identified in a class of lepidopteran hemocytes and experimentally linked to the release of prophenoloxidase. We conclude that research into PGs and their receptors in insects will lead to important advances in our understanding of insect biology.

  16. Distribution of cellular HSV-1 receptor expression in human brain.

    Science.gov (United States)

    Lathe, Richard; Haas, Juergen G

    2017-06-01

    Herpes simplex virus type 1 (HSV-1) is a neurotropic virus linked to a range of acute and chronic neurological disorders affecting distinct regions of the brain. Unusually, HSV-1 entry into cells requires the interaction of viral proteins glycoprotein D (gD) and glycoprotein B (gB) with distinct cellular receptor proteins. Several different gD and gB receptors have been identified, including TNFRSF14/HVEM and PVRL1/nectin 1 as gD receptors and PILRA, MAG, and MYH9 as gB receptors. We investigated the expression of these receptor molecules in different areas of the adult and developing human brain using online transcriptome databases. Whereas all HSV-1 receptors showed distinct expression patterns in different brain areas, the Allan Brain Atlas (ABA) reported increased expression of both gD and gB receptors in the hippocampus. Specifically, for PVRL1, TNFRFS14, and MYH9, the differential z scores for hippocampal expression, a measure of relative levels of increased expression, rose to 2.9, 2.9, and 2.5, respectively, comparable to the z score for the archetypical hippocampus-enriched mineralocorticoid receptor (NR3C2, z = 3.1). These data were confirmed at the Human Brain Transcriptome (HBT) database, but HBT data indicate that MAG expression is also enriched in hippocampus. The HBT database allowed the developmental pattern of expression to be investigated; we report that all HSV1 receptors markedly increase in expression levels between gestation and the postnatal/adult periods. These results suggest that differential receptor expression levels of several HSV-1 gD and gB receptors in the adult hippocampus are likely to underlie the susceptibility of this brain region to HSV-1 infection.

  17. Glutamate receptor ligands

    DEFF Research Database (Denmark)

    Guldbrandt, Mette; Johansen, Tommy N; Frydenvang, Karla Andrea

    2002-01-01

    Homologation and substitution on the carbon backbone of (S)-glutamic acid [(S)-Glu, 1], as well as absolute stereochemistry, are structural parameters of key importance for the pharmacological profile of (S)-Glu receptor ligands. We describe a series of methyl-substituted 2-aminoadipic acid (AA...

  18. Ginkgolides and glycine receptors

    DEFF Research Database (Denmark)

    Jaracz, Stanislav; Nakanishi, Koji; Jensen, Anders A.

    2004-01-01

    Ginkgolides from the Ginkgo biloba tree are diterpenes with a cage structure consisting of six five-membered rings and a unique tBu group. They exert a variety of biological properties. In addition to being antagonists of the platelet activating factor receptor (PAFR), it has recently been shown ...

  19. adrenergic receptor with preeclampsia

    African Journals Online (AJOL)

    User

    2011-05-09

    May 9, 2011 ... due to a post- receptor defect (Karadas et al., 2007). Several polymorphisms have ... the detection of the Arg16Gly polymorphism, overnight digestion at. 37°C with 10 U ..... DW, Wood AJ, Stein CM (2004). Beta2-adrenoceptor ...

  20. Metformin and insulin receptors

    International Nuclear Information System (INIS)

    Vigneri, R.; Gullo, D.; Pezzino, V.

    1984-01-01

    The authors evaluated the effect of metformin (N,N-dimethylbiguanide), a biguanide known to be less toxic than phenformin, on insulin binding to its receptors, both in vitro and in vivo. Specific 125 I-insulin binding to cultured IM-9 human lymphocytes and MCF-7 human breast cancer cells was determined after preincubation with metformin. Specific 125 I-insulin binding to circulating monocytes was also evaluated in six controls, eight obese subjects, and six obese type II diabetic patients before and after a short-term treatment with metformin. Plasma insulin levels and blood glucose were also measured on both occasions. Metformin significantly increased insulin binding in vitro to both IM-9 lymphocytes and MCF-7 cells; the maximum increment was 47.1% and 38.0%, respectively. Metformin treatment significantly increased insulin binding in vivo to monocytes of obese subjects and diabetic patients. Scatchard analysis indicated that the increased binding was mainly due to an increase in receptor capacity. Insulin binding to monocytes of normal controls was unchanged after metformin as were insulin levels in all groups; blood glucose was significantly reduced after metformin only in diabetic patients. These data indicate that metformin increases insulin binding to its receptors in vitro and in vivo. The effect in vivo is observed in obese subjects and in obese type II diabetic patients, paralleling the clinical effectiveness of this antidiabetic agent, and is not due to receptor regulation by circulating insulin, since no variation in insulin levels was recorded

  1. TARPs differentially decorate AMPA receptors to specify neuropharmacology.

    Science.gov (United States)

    Kato, Akihiko S; Gill, Martin B; Yu, Hong; Nisenbaum, Eric S; Bredt, David S

    2010-05-01

    Transmembrane AMPA receptor regulatory proteins (TARPs) are the first identified auxiliary subunits for a neurotransmitter-gated ion channel. Although initial studies found that stargazin, the prototypical TARP, principally chaperones AMPA receptors, subsequent research demonstrated that it also regulates AMPA receptor kinetics and synaptic waveforms. Recent studies have identified a diverse collection of TARP isoforms--types Ia, Ib II--that distinctly regulate AMPA receptor trafficking, gating and neuropharmacology. These TARP isoforms are heterogeneously expressed in specific neuronal populations and can differentially sculpt synaptic transmission and plasticity. Whole-genome analyses also link multiple TARP loci to childhood epilepsy, schizophrenia and bipolar disorder. TARPs emerge as vital components of excitatory synapses that participate both in signal transduction and in neuropsychiatric disorders. Copyright 2010 Elsevier Ltd. All rights reserved.

  2. Neurotensin receptors in human neoplasms: high incidence in Ewing's sarcomas.

    Science.gov (United States)

    Reubi, J C; Waser, B; Schaer, J C; Laissue, J A

    1999-07-19

    Receptors for regulatory peptides, such as somatostatin or vasoactive intestinal peptide (VIP), expressed at high density by neoplastic cells, can be instrumental for tumor diagnosis and therapy. Little is known about the expression of neurotensin receptors in human tumors. In the present study, 464 human neoplasms of various types were investigated for their neurotensin receptor content by in vitro receptor autoradiography on tissue sections using 125I-[Tyr3]-neurotensin as radioligand. Neurotensin receptors were identified and localized in tumor cells of 11/17 Ewing's sarcomas, 21/40 meningiomas, 10/23 astrocytomas, 5/13 medulloblastomas, 7/24 medullary thyroid cancers and 2/8 small cell lung cancers. They were rarely found in non-small cell lung cancers and breast carcinomas; they were absent in prostate, ovarian, renal cell and hepatocellular carcinomas, neuroendocrine gut tumors, pituitary adenomas, schwannomas, neuroblastomas and lymphomas. When present, the receptors bound with nanomolar affinity neurotensin and acetyl-neurotensin-(8-13), with lower affinity neuromedin N, diethylenetriamine penta-acetic acidneurotensin-(8-13) and SR 48692, but not neurotensin-(1-11). They were all of the NT1 type, without high affinity for levocabastine. Further, in 2 receptor-positive Ewing's sarcomas, neurotensin mRNA was detected by in situ hybridization techniques. Since neurotensin is known to stimulate cell proliferation, the presence of neurotensin receptors in human neoplasia may be of biological relevance, possibly as an integrative part of an autocrine feedback mechanism of tumor growth stimulation.

  3. Epilepsy, E/I balance and GABAA receptor plasticity

    Directory of Open Access Journals (Sweden)

    Jean-Marc Fritschy

    2008-03-01

    Full Text Available GABAA receptors mediate most of the fast inhibitory transmission in the CNS. They form heteromeric complexes assembled from a large family of subunit genes. The existence of multiple GABAA receptor subtypes differing in subunit composition, localization and functional properties underlies their role for fi ne-tuning of neuronal circuits and genesis of network oscillations. The differential regulation of GABAA receptor subtypes represents a major facet of homeostatic synaptic plasticity and contributes to the excitation/inhibition (E/I balance under physiological conditions and upon pathological challenges. The purpose of this review is to discuss recent fi ndings highlighting the signifi cance of GABAA receptor heterogeneity for the concept of E/I balance and its relevance for epilepsy. Specifi cally, we address the following issues: (1 role for tonic inhibition, mediated by extrasynaptic GABAA receptors, for controlling neuronal excitability; (2 signifi cance of chloride ion transport for maintenance of the E/I balance in adult brain; and (3 molecular mechanisms underlying GABAA receptor regulation (traffi cking, posttranslational modifi cation, gene transcription that are important for homoeostatic plasticity. Finally, the relevance of these fi ndings is discussed in light of the involvement of GABAA receptors in epileptic disorders, based on recent experimental studies of temporal lobe epilepsy (TLE and absence seizures and on the identifi cation of mutations in GABAA receptor subunit genes underlying familial forms of epilepsy.

  4. Angiotensin receptors and norepinephrine neuromodulation: implications of functional coupling.

    Science.gov (United States)

    Gelband, C H; Sumners, C; Lu, D; Raizada, M K

    1998-02-27

    The objective of this review is to examine the role of neuronal angiotensin II (Ang II) receptors in vitro. Two types of G protein-coupled Ang II receptors have been identified in cardiovascularly relevant areas of the brain: the AT1 and the AT2. We have utilized neurons in culture to study the signaling mechanisms of AT1 and AT2 receptors. Neuronal AT1 receptors are involved in norepinephrine (NE) neuromodulation. NE neuromodulation can be either evoked or enhanced. Evoked NE neuromodulation involves AT1 receptor-mediated, losartan-dependent, rapid NE release, inhibition of K+ channels and stimulation of Ca2+ channels. AT1 receptor-mediated enhanced NE neuromodulation involves the Ras-Raf-MAP kinase cascade and ultimately leads to an increase in NE transporter, tyrosine hydroxylase and dopamine beta-hydroxylase mRNA transcription. Neuronal AT2 receptors signal via a Gi protein and are coupled to activation of PP2A and PLA2 and stimulation of K+ channels. Finally, putative cross-talk pathways between AT1 and AT2 receptors will be discussed.

  5. A regulatory code for neuron-specific odor receptor expression.

    Directory of Open Access Journals (Sweden)

    Anandasankar Ray

    2008-05-01

    Full Text Available Olfactory receptor neurons (ORNs must select-from a large repertoire-which odor receptors to express. In Drosophila, most ORNs express one of 60 Or genes, and most Or genes are expressed in a single ORN class in a process that produces a stereotyped receptor-to-neuron map. The construction of this map poses a problem of receptor gene regulation that is remarkable in its dimension and about which little is known. By using a phylogenetic approach and the genome sequences of 12 Drosophila species, we systematically identified regulatory elements that are evolutionarily conserved and specific for individual Or genes of the maxillary palp. Genetic analysis of these elements supports a model in which each receptor gene contains a zip code, consisting of elements that act positively to promote expression in a subset of ORN classes, and elements that restrict expression to a single ORN class. We identified a transcription factor, Scalloped, that mediates repression. Some elements are used in other chemosensory organs, and some are conserved upstream of axon-guidance genes. Surprisingly, the odor response spectra and organization of maxillary palp ORNs have been extremely well-conserved for tens of millions of years, even though the amino acid sequences of the receptors are not highly conserved. These results, taken together, define the logic by which individual ORNs in the maxillary palp select which odor receptors to express.

  6. Personal receptor repertoires: olfaction as a model

    Directory of Open Access Journals (Sweden)

    Olender Tsviya

    2012-08-01

    Full Text Available Abstract Background Information on nucleotide diversity along completely sequenced human genomes has increased tremendously over the last few years. This makes it possible to reassess the diversity status of distinct receptor proteins in different human individuals. To this end, we focused on the complete inventory of human olfactory receptor coding regions as a model for personal receptor repertoires. Results By performing data-mining from public and private sources we scored genetic variations in 413 intact OR loci, for which one or more individuals had an intact open reading frame. Using 1000 Genomes Project haplotypes, we identified a total of 4069 full-length polypeptide variants encoded by these OR loci, average of ~10 per locus, constituting a lower limit for the effective human OR repertoire. Each individual is found to harbor as many as 600 OR allelic variants, ~50% higher than the locus count. Because OR neuronal expression is allelically excluded, this has direct effect on smell perception diversity of the species. We further identified 244 OR segregating pseudogenes (SPGs, loci showing both intact and pseudogene forms in the population, twenty-six of which are annotatively “resurrected” from a pseudogene status in the reference genome. Using a custom SNP microarray we validated 150 SPGs in a cohort of 468 individuals, with every individual genome averaging 36 disrupted sequence variations, 15 in homozygote form. Finally, we generated a multi-source compendium of 63 OR loci harboring deletion Copy Number Variations (CNVs. Our combined data suggest that 271 of the 413 intact OR loci (66% are affected by nonfunctional SNPs/indels and/or CNVs. Conclusions These results portray a case of unusually high genetic diversity, and suggest that individual humans have a highly personalized inventory of functional olfactory receptors, a conclusion that might apply to other receptor multigene families.

  7. G protein-coupled receptors in Anopheles gambiae.

    Science.gov (United States)

    Hill, Catherine A; Fox, A Nicole; Pitts, R Jason; Kent, Lauren B; Tan, Perciliz L; Chrystal, Mathew A; Cravchik, Anibal; Collins, Frank H; Robertson, Hugh M; Zwiebel, Laurence J

    2002-10-04

    We used bioinformatic approaches to identify a total of 276 G protein-coupled receptors (GPCRs) from the Anopheles gambiae genome. These include GPCRs that are likely to play roles in pathways affecting almost every aspect of the mosquito's life cycle. Seventy-nine candidate odorant receptors were characterized for tissue expression and, along with 76 putative gustatory receptors, for their molecular evolution relative to Drosophila melanogaster. Examples of lineage-specific gene expansions were observed as well as a single instance of unusually high sequence conservation.

  8. [Roles of G protein-coupled estrogen receptor in the male reproductive system].

    Science.gov (United States)

    Chen, Kai-hong; Zhang, Xian; Jiang, Xue-wu

    2016-02-01

    The G protein-coupled estrogen receptor (GPER), also known as G protein-coupled receptor 30 (GPR30), was identified in the recent years as a functional membrane receptor different from the classical nuclear estrogen receptors. This receptor is widely expressed in the cortex, cerebellum, hippocampus, heart, lung, liver, skeletal muscle, and the urogenital system. It is responsible for the mediation of nongenomic effects associated with estrogen and its derivatives, participating in the physiological activities of the body. The present study reviews the molecular structure, subcellular localization, signaling pathways, distribution, and function of GPER in the male reproductive system.

  9. Olfactory Receptor Database: a sensory chemoreceptor resource

    OpenAIRE

    Skoufos, Emmanouil; Marenco, Luis; Nadkarni, Prakash M.; Miller, Perry L.; Shepherd, Gordon M.

    2000-01-01

    The Olfactory Receptor Database (ORDB) is a WWW-accessible database that has been expanded from an olfactory receptor resource to a chemoreceptor resource. It stores data on six classes of G-protein-coupled sensory chemoreceptors: (i) olfactory receptor-like proteins, (ii) vomeronasal receptors, (iii) insect olfactory receptors, (iv) worm chemoreceptors, (v) taste papilla receptors and (vi) fungal pheromone receptors. A complementary database of the ligands of these receptors (OdorDB) has bee...

  10. Receptor Autoradiography Protocol for the Localized Visualization of Angiotensin II Receptors.

    Science.gov (United States)

    Linares, Andrea; Couling, Leena E; Carrera, Eduardo J; Speth, Robert C

    2016-06-07

    This protocol describes receptor binding patterns for Angiotensin II (Ang II) in the rat brain using a radioligand specific for Ang II receptors to perform receptor autoradiographic mapping. Tissue specimens are harvested and stored at -80 °C. A cryostat is used to coronally section the tissue (brain) and thaw-mount the sections onto charged slides. The slide-mounted tissue sections are incubated in (125)I-SI-Ang II to radiolabel Ang II receptors. Adjacent slides are separated into two sets: 'non-specific binding' (NSP) in the presence of a receptor saturating concentration of non-radiolabeled Ang II, or an AT1 Ang II receptor subtype (AT1R) selective Ang II receptor antagonist, and 'total binding' with no AT1R antagonist. A saturating concentration of AT2 Ang II receptor subtype (AT2R) antagonist (PD123319, 10 µM) is also present in the incubation buffer to limit (125)I-SI-Ang II binding to the AT1R subtype. During a 30 min pre-incubation at ~22 °C, NSP slides are exposed to 10 µM PD123319 and losartan, while 'total binding' slides are exposed to 10 µM PD123319. Slides are then incubated with (125)I-SI-Ang II in the presence of PD123319 for 'total binding', and PD123319 and losartan for NSP in assay buffer, followed by several 'washes' in buffer, and water to remove salt and non-specifically bound radioligand. The slides are dried using blow-dryers, then exposed to autoradiography film using a specialized film and cassette. The film is developed and the images are scanned into a computer for visual and quantitative densitometry using a proprietary imaging system and a spreadsheet. An additional set of slides are thionin-stained for histological comparisons. The advantage of using receptor autoradiography is the ability to visualize Ang II receptors in situ, within a section of a tissue specimen, and anatomically identify the region of the tissue by comparing it to an adjacent histological reference section.

  11. The non-biphenyl-tetrazole angiotensin AT1 receptor antagonist eprosartan is a unique and robust inverse agonist of the active state of the AT1 receptor.

    Science.gov (United States)

    Takezako, Takanobu; Unal, Hamiyet; Karnik, Sadashiva S; Node, Koichi

    2018-03-23

    Conditions such as hypertension and renal allograft rejection are accompanied by chronic, agonist-independent, signalling by angiotensin II AT 1 receptors. The current treatment paradigm for these diseases entails the preferred use of inverse agonist AT 1 receptor blockers (ARBs). However, variability in the inverse agonist activities of common biphenyl-tetrazole ARBs for the active state of AT 1 receptors often leads to treatment failure. Therefore, characterization of robust inverse agonist ARBs for the active state of AT 1 receptors is necessary. To identify the robust inverse agonist for active state of AT 1 receptors and its molecular mechanism, we performed site-directed mutagenesis, competition binding assay, inositol phosphate production assay and molecular modelling for both ground-state wild-type AT 1 receptors and active-state N111G mutant AT 1 receptors. Although candesartan and telmisartan exhibited weaker inverse agonist activity for N111G- compared with WT-AT 1 receptors, only eprosartan exhibited robust inverse agonist activity for both N111G- and WT- AT 1 receptors. Specific ligand-receptor contacts for candesartan and telmisartan are altered in the active-state N111G- AT 1 receptors compared with the ground-state WT-AT 1 receptors, suggesting an explanation of their attenuated inverse agonist activity for the active state of AT 1 receptors. In contrast, interactions between eprosartan and N111G-AT 1 receptors were not significantly altered, and the inverse agonist activity of eprosartan was robust. Eprosartan may be a better therapeutic option than other ARBs. Comparative studies investigating eprosartan and other ARBs for the treatment of diseases caused by chronic, agonist-independent, AT 1 receptor activation are warranted. © 2018 The British Pharmacological Society.

  12. Differential modulation of Beta-adrenergic receptor signaling by trace amine-associated receptor 1 agonists.

    Directory of Open Access Journals (Sweden)

    Gunnar Kleinau

    Full Text Available Trace amine-associated receptors (TAAR are rhodopsin-like G-protein-coupled receptors (GPCR. TAAR are involved in modulation of neuronal, cardiac and vascular functions and they are potentially linked with neurological disorders like schizophrenia and Parkinson's disease. Subtype TAAR1, the best characterized TAAR so far, is promiscuous for a wide set of ligands and is activated by trace amines tyramine (TYR, phenylethylamine (PEA, octopamine (OA, but also by thyronamines, dopamine, and psycho-active drugs. Unfortunately, effects of trace amines on signaling of the two homologous β-adrenergic receptors 1 (ADRB1 and 2 (ADRB2 have not been clarified yet in detail. We, therefore, tested TAAR1 agonists TYR, PEA and OA regarding their effects on ADRB1/2 signaling by co-stimulation studies. Surprisingly, trace amines TYR and PEA are partial allosteric antagonists at ADRB1/2, whereas OA is a partial orthosteric ADRB2-antagonist and ADRB1-agonist. To specify molecular reasons for TAAR1 ligand promiscuity and for observed differences in signaling effects on particular aminergic receptors we compared TAAR, tyramine (TAR octopamine (OAR, ADRB1/2 and dopamine receptors at the structural level. We found especially for TAAR1 that the remarkable ligand promiscuity is likely based on high amino acid similarity in the ligand-binding region compared with further aminergic receptors. On the other hand few TAAR specific properties in the ligand-binding site might determine differences in ligand-induced effects compared to ADRB1/2. Taken together, this study points to molecular details of TAAR1-ligand promiscuity and identified specific trace amines as allosteric or orthosteric ligands of particular β-adrenergic receptor subtypes.

  13. Identification and Characterization of Pheromone Receptors and Interplay between Receptors and Pheromone Binding Proteins in the Diamondback Moth, Plutella xyllostella

    OpenAIRE

    Sun, Mengjing; Liu, Yang; Walker, William B.; Liu, Chengcheng; Lin, Kejian; Gu, Shaohua; Zhang, Yongjun; Zhou, Jingjiang; Wang, Guirong

    2013-01-01

    Moths depend on olfactory cues such as sex pheromones to find and recognize mating partners. Pheromone receptors (PRs) and Pheromone binding proteins (PBPs) are thought to be associated with olfactory signal transduction of pheromonal compounds in peripheral olfactory reception. Here six candidate pheromone receptor genes in the diamondback moth, Plutella xyllostella were identified and cloned. All of the six candidate PR genes display male-biased expression, which is a typical characteristic...

  14. Three nuclear and two membrane estrogen receptors in basal teleosts, Anguilla sp.: Identification, evolutionary history and differential expression regulation

    DEFF Research Database (Denmark)

    Lafont, Anne Gaëlle; Rousseau, Karine; Tomkiewicz, Jonna

    2016-01-01

    Estrogens interact with classical intracellular nuclear receptors (ESR), and with G-coupled membrane receptors (GPER). In the eel, we identified three nuclear (ESR1, ESR2a, ESR2b) and two membrane (GPERa, GPERb) estrogen receptors. Duplicated ESR2 and GPER were also retrieved in most extant teleo...

  15. Prostaglandin Receptor Signaling in Disease

    Directory of Open Access Journals (Sweden)

    Toshiyuki Matsuoka

    2007-01-01

    Full Text Available Prostanoids, consisting of the prostaglandins (PGs and the thromboxanes (TXs, are a group of lipid mediators formed in response to various stimuli. They include PGD2, PGE2, PGF2α, PGI2, and TXA2. They are released outside of the cells immediately after synthesis, and exert their actions by binding to a G-protein coupled rhodopsin-type receptor on the surface of target cells. There are eight types of the prostanoid receptors conserved in mammals from mouse to human. They are the PGD receptor (DP, four subtypes of the PGE receptor (EP1, EP2, EP3, and EP4, the PGF receptor (FP, PGI receptor (IP, and TXA receptor (TP. Recently, mice deficient in each of these prostanoid receptors were generated and subjected to various experimental models of disease. These studies have revealed the roles of PG receptor signaling in various pathological conditions, and suggest that selective manipulation of the prostanoid receptors may be beneficial in treatment of the pathological conditions. Here we review these recent findings of roles of prostanoid receptor signaling and their therapeutic implications.

  16. The interleukin-4 receptor: signal transduction by a hematopoietin receptor.

    Science.gov (United States)

    Keegan, A D; Pierce, J H

    1994-02-01

    Over the last several years, the receptors for numerous cytokines have been molecularly characterized. Analysis of their amino acid sequences shows that some of these receptors bear certain motifs in their extracellular domains that define a family of receptors called the Hematopoietin receptor superfamily. Significant advances in characterizing the structure, function, and mechanisms of signal transduction have been made for several members of this family. The purpose of this review is to discuss the recent advances made for one of the family members, the interleukin (IL) 4 receptor. Other receptor systems have recently been reviewed elsewhere. The IL-4 receptor consists of, at the minimum, the cloned 140 kDa IL-4-binding chain with the potential for associating with other chains. The IL-4 receptor transduces its signal by activating a tyrosine kinase that phosphorylates cellular substrates, including the receptor itself, and the 170 kDa substrate called 4PS. Phosphorylated 4PS interacts with the SH2 domain of the enzyme PI-3'-kinase and increases its enzymatic activity. These early events in the IL-4 receptor initiated signaling pathway may trigger a series of signals that will ultimately lead to an IL-4 specific biologic outcome.

  17. Meeting report: nuclear receptors

    DEFF Research Database (Denmark)

    Tuckermann, Jan; Bourguet, William; Mandrup, Susanne

    2010-01-01

    The biannual European Molecular Biology Organization (EMBO) conference on nuclear receptors was organized by Beatrice Desvergne and Laszlo Nagy and took place in Cavtat near Dubrovnik on the Adriatic coast of Croatia September 25-29, 2009. The meeting brought together researchers from all over...... the world covering a wide spectrum from fundamental mechanistic studies to metabolism, clinical studies, and drug development. In this report, we summarize the recent and exciting findings presented by the speakers at the meeting....

  18. Neurotransmitter receptor imaging

    International Nuclear Information System (INIS)

    Cordes, M.; Hierholzer, J.; Nikolai-Beyer, K.

    1993-01-01

    The importance of neuroreceptor imaging in vivo using single photon emission tomography (SPECT) and positron emission tomography (PET) has increased enormously. The principal neurotransmitters, such as dopamine, GABA/benzodiazepine, acetylcholine, and serotonin, are presented with reference to anatomical, biochemical, and physiological features. The main radioligands for SPECT and PET are introduced, and methodological characteristics of both PET and SPECT presented. Finally, the results of neurotransmitter receptor imaging obtained so far will be discussed. (orig.) [de

  19. Thyroid Stimulating Hormone Receptor

    Directory of Open Access Journals (Sweden)

    Murat Tuncel

    2017-02-01

    Full Text Available Thyroid stimulating hormone receptor (TSHR plays a pivotal role in thyroid hormone metabolism. It is a major controller of thyroid cell function and growth. Mutations in TSHR may lead to several thyroid diseases, most commonly hyperthyroidism. Although its genetic and epigenetic alterations do not directly lead to carcinogenesis, it has a crucial role in tumor growth, which is initiated by several oncogenes. This article will provide a brief review of TSHR and related diseases.

  20. Enhancement of insulin-like growth factor 2 receptors in glioblastoma

    International Nuclear Information System (INIS)

    Sara, V.; Prisell, Per; Sjoegren, Barbro; Enberg, Goesta

    1986-01-01

    The somatomedins (IGF-1/IGF-2) are a family of growth-promoting hormones which have been identified in the human central nervous system where their specific receptors are distributed. The present study identified somatomedin receptors in glioblastoma and compared them with those found in normal brain. A significant enhancement in the binding of 125 1-IGF-2 but not 125 1-IGF-1 to glioblastoma membranes was found. A fourfold increase in IGF-2 receptor concentration was observed. These findings indicate enhanced expression of the IGF-2 receptor in glioblastoma. (author)

  1. Enhancement of insulin-like growth factor 2 receptors in glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Sara, V; Prisell, P; Sjoegren, B; Persson, L; Boethius, J; Enberg, G

    1986-09-01

    The somatomedins (IGF-1/IGF-2) are a family of growth-promoting hormones which have been identified in the human central nervous system where their specific receptors are distributed. The present study identified somatomedin receptors in glioblastoma and compared them with those found in normal brain. A significant enhancement in the binding of /sup 125/1-IGF-2 but not /sup 125/1-IGF-1 to glioblastoma membranes was found. A fourfold increase in IGF-2 receptor concentration was observed. These findings indicate enhanced expression of the IGF-2 receptor in glioblastoma. 14 refs.

  2. Association of dopamine D(3) receptors with actin-binding protein 280 (ABP-280).

    Science.gov (United States)

    Li, Ming; Li, Chuanyu; Weingarten, Paul; Bunzow, James R; Grandy, David K; Zhou, Qun Yong

    2002-03-01

    Proteins that bind to G protein-coupled receptors have been identified as regulators of receptor localization and signaling. In our previous studies, a cytoskeletal protein, actin-binding protein 280 (ABP-280), was found to associate with the third cytoplasmic loop of dopamine D(2) receptors. In this study, we demonstrate that ABP-280 also interacts with dopamine D(3) receptors, but not with D(4) receptors. Similar to the dopamine D(2) receptor, the D(3)/ABP-280 association is of signaling importance. In human melanoma M2 cells lacking ABP-280, D(3) receptors were unable to inhibit forskolin-stimulated cyclic AMP (cAMP) production significantly. D(4) receptors, however, exhibited a similar degree of inhibition of forskolin-stimulated cAMP production in ABP-280-deficient M2 cells and ABP-280-replent M2 subclones (A7 cells). Further experiments revealed that the D(3)/ABP-280 interaction was critically dependent upon a 36 amino acid carboxyl domain of the D(3) receptor third loop, which is conserved in the D(2) receptor but not in the D(4) receptor. Our results demonstrate a subtype-specific regulation of dopamine D(2)-family receptor signaling by the cytoskeletal protein ABP-280.

  3. Teleost Chemokines and Their Receptors

    Directory of Open Access Journals (Sweden)

    Steve Bird

    2015-11-01

    Full Text Available Chemokines are a superfamily of cytokines that appeared about 650 million years ago, at the emergence of vertebrates, and are responsible for regulating cell migration under both inflammatory and physiological conditions. The first teleost chemokine gene was reported in rainbow trout in 1998. Since then, numerous chemokine genes have been identified in diverse fish species evidencing the great differences that exist among fish and mammalian chemokines, and within the different fish species, as a consequence of extensive intrachromosomal gene duplications and different infectious experiences. Subsequently, it has only been possible to establish clear homologies with mammalian chemokines in the case of some chemokines with well-conserved homeostatic roles, whereas the functionality of other chemokine genes will have to be independently addressed in each species. Despite this, functional studies have only been undertaken for a few of these chemokine genes. In this review, we describe the current state of knowledge of chemokine biology in teleost fish. We have mainly focused on those species for which more research efforts have been made in this subject, specially zebrafish (Danio rerio, rainbow trout (Oncorhynchus mykiss and catfish (Ictalurus punctatus, outlining which genes have been identified thus far, highlighting the most important aspects of their expression regulation and addressing any known aspects of their biological role in immunity. Finally, we summarise what is known about the chemokine receptors in teleosts and provide some analysis using recently available data to help characterise them more clearly.

  4. Biological roles and therapeutic potential of hydroxy-carboxylic acid receptors

    Directory of Open Access Journals (Sweden)

    Kashan eAhmed

    2011-10-01

    Full Text Available In the recent past, deorphanization studies have described intermediates of energy metabolism to activate G protein-coupled receptors (GPCRs and to thereby regulate metabolic functions. GPR81, GPR109A and GPR109B, formerly known as the nicotinic acid receptor family, are encoded by clustered genes and share a high degree of sequence homology. Recently, hydroxy-carboxylic acids were identified as endogenous ligands of GPR81, GPR109A and GPR109B, and therefore these receptors have been placed into a novel receptor family of hydroxy-carboxylic acid (HCA receptors. The HCA1 receptor (GPR81 is activated by the glycolytic metabolite 2-hydroxy-propionic acid (lactate, the HCA2 receptor is activated by the ketone body 3-hydroxy-butyric acid and the HCA3 receptor (GPR109B is a receptor for the β-oxidation intermediate 3-hydroxy-octanoic acid. While HCA1 and HCA2 receptors are present in most mammalian species, the HCA3 receptor is exclusively found in humans and higher primates. HCA receptors are expressed in adipose tissue and mediate anti-lipolytic effects in adipocytes through Gi-type G-protein-dependent inhibition of adenylyl cyclase. HCA2 and HCA3 inhibit lipolysis during conditions of increased β-oxidation such as prolonged fasting, whereas HCA1 mediates the anti-lipolytic effects of insulin in the fed state. As HCA2 is a receptor for the established anti-dyslipidemic drug nicotinic acid, HCA1 and HCA3 also represent promising drug targets and several synthetic ligands for HCA receptors have been developed. In this article, we will summarize the deorphanization and pharmacological characterization of HCA receptors. Moreover, we will discuss recent progress in elucidating the physiological and pathophysiological role to further evaluate the therapeutic potential of the HCA receptor family for the treatment of metabolic disease.

  5. CLONING AND IN VITRO EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR α FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    Science.gov (United States)

    In vitro screening assays designed to identify hormone mimics or antagonists typically use mammalian (rat, human) estrogen (ER) and androgen receptors (AR). Although we know that the amino acid sequences of steroid receptors in nonmammalian vertebrates are not identical to the ma...

  6. Near Identifiability of Dynamical Systems

    Science.gov (United States)

    Hadaegh, F. Y.; Bekey, G. A.

    1987-01-01

    Concepts regarding approximate mathematical models treated rigorously. Paper presents new results in analysis of structural identifiability, equivalence, and near equivalence between mathematical models and physical processes they represent. Helps establish rigorous mathematical basis for concepts related to structural identifiability and equivalence revealing fundamental requirements, tacit assumptions, and sources of error. "Structural identifiability," as used by workers in this field, loosely translates as meaning ability to specify unique mathematical model and set of model parameters that accurately predict behavior of corresponding physical system.

  7. Glucocorticoid Regulation of the Vitamin D Receptor

    Science.gov (United States)

    Hidalgo, Alejandro A.; Trump, Donald L.; Johnson, Candace S.

    2010-01-01

    Many studies indicate calcitriol has potent anti-tumor activity in different types of cancers. However, high levels of vitamin D can produce hypercalcemia in some patients. Glucocorticoids are used to ameliorate hypercalcemia and to enhance calcitriol anti-tumor activity. Calcitriol in combination with the glucocorticoid dexamethasone (Dex) increased vitamin D receptor (VDR) protein levels and ligand binding in squamous cell carcinoma VII (SCC). In this study we found that both calcitriol and Dex induce VDR- and glucocorticoid receptor (GR)-mediated transcription respectively, indicating both hormone receptors are active in SCC. Pre-treatment with Dex increases VDR-mediated transcription at the human CYP24A1 promoter. Whereas, pre-treatment with other steroid hormones, including dihydrotestosterone and R1881, has no effect on VDR-mediated transcription. Real-time PCR indicates treatment with Dex increases Vdr transcripts in a time-dependent manner, suggesting Dex may directly regulate expression of Vdr. Numerous putative glucocorticoid response elements (GREs) were found in the Vdr gene. Chromatin immunoprecipitation (ChIP) assay demonstrated GR binding at several putative GREs located within the mouse Vdr gene. However, none of the putative GREs studied increase GR-mediated transcription in luciferase reporter assays. In an attempt to identify the response element responsible for Vdr transcript regulation, future studies will continue to analyze newly identified GREs more distal from the Vdr gene promoter. PMID:20398752

  8. Upregulation of Leukotriene Receptors in Gastric Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Venerito, Marino [Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg 39120 (Germany); Kuester, Doerthe [Institute of Pathology, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg 39120 (Germany); Harms, Caroline [Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg 39120 (Germany); Schubert, Daniel [Department of General, Visceral and Vascular Surgery, Otto-von-Guericke University Magdeburg, Leipziger Str. 44, Magdeburg 39120 (Germany); Wex, Thomas, E-mail: thomas.wex@med.ovgu.de; Malfertheiner, Peter [Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg 39120 (Germany)

    2011-08-08

    Leukotrienes (LT) mediate allergic and inflammatory processes. Previously, we identified significant changes in the expression pattern of LT receptors in the gastric mucosa after eradication of Helicobacter pylori infection. The aim of the present study was to evaluate the expression of 5-lipoxygenase (5-LOX) and LT receptors in gastric cancer (GC). The expression of 5-LOX and receptors for LTB4 (BLT-1, BLT-2) and cysteinyl-LT (CysLT-1, CysLT-2) were analyzed by immunohistochemistry (IHC) in GC samples of 35 consecutive patients who underwent gastrectomy and in 29 tumor-free tissue specimens from gastric mucosa. Male-to-female ratio was 24:11. The median age was 70 years (range 34–91). Twenty-two patients had GC of intestinal, six of diffuse, six of mixed and one of undifferentiated type. The IHC analysis showed a nearly ubiquitous expression of studied proteins in GC (88–97%) and in tumor-free specimens as well (89–100%). An increase in the immunoreactive score of both BLT receptors and CysLT-1 was observed in GC compared to tumor-free gastric mucosa (p < 0.001 for BLT-1; p < 0.01 for BLT-2 and CysLT-1, Mann-Whitney U-test). No differences in the IHC expression of 5-LOX and CsyLT-2 were observed between GC and tumor-free mucosa. The expression of BLT-2, CysLT-1 and CysLT-2 was increased in GC of intestinal type when compared to the diffuse type (p < 0.05; Mann-Whitney U-test). LTB4 receptors and CysLT-1 are up-regulated in GC tissue implying a role in gastric carcinogenesis.

  9. Expression of estrogen and progesterone receptors in astrocytomas: a literature review

    Directory of Open Access Journals (Sweden)

    Cléciton Braga Tavares

    Full Text Available Gliomas are the most common type of primary central nervous system neoplasm. Astrocytomas are the most prevalent type of glioma and these tumors may be influenced by sex steroid hormones. A literature review for the presence of estrogen and progesterone receptors in astrocytomas was conducted in the PubMed database using the following MeSH terms: “estrogen receptor beta” OR “estrogen receptor alpha” OR “estrogen receptor antagonists” OR “progesterone receptors” OR “astrocytoma” OR “glioma” OR “glioblastoma”. Among the 111 articles identified, 13 studies met our inclusion criteria. The majority of reports showed the presence of estrogen and progesterone receptors in astrocytomas. Overall, higher tumor grades were associated with decreased estrogen receptor expression and increased progesterone receptor expression.

  10. Expression of estrogen and progesterone receptors in astrocytomas: a literature review

    Science.gov (United States)

    Tavares, Cléciton Braga; Gomes-Braga, Francisca das Chagas Sheyla Almeida; Costa-Silva, Danylo Rafhael; Escórcio-Dourado, Carla Solange; Borges, Umbelina Soares; Conde, Airton Mendes; da Conceição Barros-Oliveira, Maria; Sousa, Emerson Brandão; da Rocha Barros, Lorena; Martins, Luana Mota; Facina, Gil; da-Silva, Benedito Borges

    2016-01-01

    Gliomas are the most common type of primary central nervous system neoplasm. Astrocytomas are the most prevalent type of glioma and these tumors may be influenced by sex steroid hormones. A literature review for the presence of estrogen and progesterone receptors in astrocytomas was conducted in the PubMed database using the following MeSH terms: “estrogen receptor beta” OR “estrogen receptor alpha” OR “estrogen receptor antagonists” OR “progesterone receptors” OR “astrocytoma” OR “glioma” OR “glioblastoma”. Among the 111 articles identified, 13 studies met our inclusion criteria. The majority of reports showed the presence of estrogen and progesterone receptors in astrocytomas. Overall, higher tumor grades were associated with decreased estrogen receptor expression and increased progesterone receptor expression. PMID:27626480

  11. The role of GH receptor tyrosine phosphorylation in Stat5 activation

    DEFF Research Database (Denmark)

    Hansen, J A; Hansen, L H; Wang, X

    1997-01-01

    Stimulation of GH receptors leads to rapid activation of Jak2 kinase and subsequent tyrosine phosphorylation of the GH receptor. Three specific tyrosines located in the C-terminal domain of the GH receptor have been identified as being involved in GH-stimulated transcription of the Spi 2.1 promoter....... Mutated GH receptors lacking all but one of these three tyrosines are able to mediate a transcriptional response when transiently transfected into CHO cells together with a Spi 2.1 promoter/luciferase construct. Similarly, these GH receptors were found to be able to mediate activation of Stat5 DNA......-binding activity, whereas the GH receptor mutant lacking all intracellular tyrosines was not. Synthetic tyrosine phosphorylated peptides corresponding to the GH receptor sequence around the three tyrosines inhibited Stat5 DNA-binding activity while their non-phosphorylated counterparts were ineffective. Tyrosine...

  12. Dimers of G-Protein Coupled Receptors as Versatile Storage and Response Units

    Directory of Open Access Journals (Sweden)

    Michael S. Parker

    2014-03-01

    Full Text Available The status and use of transmembrane, extracellular and intracellular domains in oligomerization of heptahelical G-protein coupled receptors (GPCRs are reviewed and for transmembrane assemblies also supplemented by new experimental evidence. The transmembrane-linked GPCR oligomers typically have as the minimal unit an asymmetric ~180 kDa pentamer consisting of receptor homodimer or heterodimer and a G-protein αβγ subunit heterotrimer. With neuropeptide Y (NPY receptors, this assembly is converted to ~90 kDa receptor monomer-Gα complex by receptor and Gα agonists, and dimers/heteropentamers are depleted by neutralization of Gαi subunits by pertussis toxin. Employing gradient centrifugation, quantification and other characterization of GPCR dimers at the level of physically isolated and identified heteropentamers is feasible with labeled agonists that do not dissociate upon solubilization. This is demonstrated with three neuropeptide Y (NPY receptors and could apply to many receptors that use large peptidic agonists.

  13. Solubilization and purification of melatonin receptors from lizard brain

    International Nuclear Information System (INIS)

    Rivkees, S.A.; Conron, R.W. Jr.; Reppert, S.M.

    1990-01-01

    Melatonin receptors in lizard brain were identified and characterized using 125 I-labeled melatonin ([ 125 I]MEL) after solubilization with the detergent digitonin. Saturation studies of solubilized material revealed a high affinity binding site, with an apparent equilibrium dissociation constant of 181 +/- 45 pM. Binding was reversible and inhibited by melatonin and closely related analogs, but not by serotonin or norepinephrine. Treatment of solubilized material with the non-hydrolyzable GTP analog, guanosine 5'-(3-O-thiotriphosphate) (GTP-gamma-S), significantly reduced receptor affinity. Gel filtration chromatography of solubilized melatonin receptors revealed a high affinity, large (Mr 400,000) peak of specific binding. Pretreatment with GTP-gamma-S before solubilization resulted in elution of a lower affinity, smaller (Mr 150,000) peak of specific binding. To purify solubilized receptors, a novel affinity chromatography resin was developed by coupling 6-hydroxymelatonin with Epoxy-activated Sepharose 6B. Using this resin, melatonin receptors were purified approximately 10,000-fold. Purified material retained the pharmacologic specificity of melatonin receptors. These results show that melatonin receptors that bind ligand after detergent treatment can be solubilized and substantially purified by affinity chromatography

  14. Solubilization and purification of melatonin receptors from lizard brain.

    Science.gov (United States)

    Rivkees, S A; Conron, R W; Reppert, S M

    1990-09-01

    Melatonin receptors in lizard brain were identified and characterized using 125I-labeled melatonin ([125I]MEL) after solubilization with the detergent digitonin. Saturation studies of solubilized material revealed a high affinity binding site, with an apparent equilibrium dissociation constant of 181 +/- 45 pM. Binding was reversible and inhibited by melatonin and closely related analogs, but not by serotonin or norepinephrine. Treatment of solubilized material with the non-hydrolyzable GTP analog, guanosine 5'-(3-O-thiotriphosphate) (GTP-gamma-S), significantly reduced receptor affinity. Gel filtration chromatography of solubilized melatonin receptors revealed a high affinity, large (Mr 400,000) peak of specific binding. Pretreatment with GTP-gamma-S before solubilization resulted in elution of a lower affinity, smaller (Mr 150,000) peak of specific binding. To purify solubilized receptors, a novel affinity chromatography resin was developed by coupling 6-hydroxymelatonin with Epoxy-activated Sepharose 6B. Using this resin, melatonin receptors were purified approximately 10,000-fold. Purified material retained the pharmacologic specificity of melatonin receptors. These results show that melatonin receptors that bind ligand after detergent treatment can be solubilized and substantially purified by affinity chromatography.

  15. Anatomical and pharmacological characterization of excitatory amino acid receptors

    International Nuclear Information System (INIS)

    Monaghan, D.T.

    1985-01-01

    The majority of the excitatory neurotransmission in the vertebrate Central Nervous System is thought to be mediated by acidic amino acid neurotransmitters. However, relatively little is known about the excitatory amino acid receptors and their distribution within the CNS. By analyzing radioligand binding to purified synaptic plasma membranes and to thin tissue sections processed for autoradiography, multiple distinct binding sites were found. These binding sites exhibited the pharmacological properties indicative of the excitatory amino acid receptors, which had been identified by electrophysiological techniques. Specifically, L-[ 3 H]-glutamate and D-[ 3 H]-amino-5-phosphonopentanoate appear to label N-methyl-D-aspartate receptors, L-[ 3 H]-glutamate and [ 3 H]-kainic acid appear to label kainic acid receptors, and L-[ 3 H]-glutamate and [ 3 H]-amino-3-hydroxy-5-methyl-4-isoxazolepropionate appear to label quisqualate receptors. Together, these results confirm the three receptor scheme proposed for excitatory amino acid neurotransmission. These results also show that these transmitter-receptor systems are differentially distributed in the brain, and that the total distribution is consistent with that found by other markers for excitatory amino acid-using neurons

  16. Dopamine receptor gene expression by enkephalin neurons in rat forebrain

    International Nuclear Information System (INIS)

    Le Moine, C.; Normand, E.; Guitteny, A.F.; Fouque, B.; Teoule, R.; Bloch, B.

    1990-01-01

    In situ hybridization experiments were performed with brain sections from normal, control and haloperidol-treated rats to identify and map the cells expressing the D2 dopamine receptor gene. D2 receptor mRNA was detected with radioactive or biotinylated oligonucleotide probes. D2 receptor mRNA was present in glandular cells of the pituitary intermediate lobe and in neurons of the substantia nigra, ventral tegmental area, and forebrain, especially in caudate putamen, nucleus accumbens, olfactory tubercle, and piriform cortex. Hybridization with D2 and preproenkephalin A probes in adjacent sections, as well as combined hybridization with the two probes in the same sections, demonstrated that all detectable enkephalin neurons in the striatum contained the D2 receptor mRNA. Large neurons in caudate putamen, which were unlabeled with the preproenkephalin A probe and which may have been cholinergic, also expressed the D2 receptor gene. Haloperidol treatment (14 or 21 days) provoked an increase in mRNA content for D2 receptor and preproenkephalin A in the striatum. This suggests that the increase in D2 receptor number observed after haloperidol treatment is due to increased activity of the D2 gene. These results indicate that in the striatum, the enkephalin neurons are direct targets for dopamine liberated from mesostriatal neurons

  17. Dopamine receptor gene expression by enkephalin neurons in rat forebrain

    Energy Technology Data Exchange (ETDEWEB)

    Le Moine, C.; Normand, E.; Guitteny, A.F.; Fouque, B.; Teoule, R.; Bloch, B. (Universite de Bordeaux II (France))

    1990-01-01

    In situ hybridization experiments were performed with brain sections from normal, control and haloperidol-treated rats to identify and map the cells expressing the D2 dopamine receptor gene. D2 receptor mRNA was detected with radioactive or biotinylated oligonucleotide probes. D2 receptor mRNA was present in glandular cells of the pituitary intermediate lobe and in neurons of the substantia nigra, ventral tegmental area, and forebrain, especially in caudate putamen, nucleus accumbens, olfactory tubercle, and piriform cortex. Hybridization with D2 and preproenkephalin A probes in adjacent sections, as well as combined hybridization with the two probes in the same sections, demonstrated that all detectable enkephalin neurons in the striatum contained the D2 receptor mRNA. Large neurons in caudate putamen, which were unlabeled with the preproenkephalin A probe and which may have been cholinergic, also expressed the D2 receptor gene. Haloperidol treatment (14 or 21 days) provoked an increase in mRNA content for D2 receptor and preproenkephalin A in the striatum. This suggests that the increase in D2 receptor number observed after haloperidol treatment is due to increased activity of the D2 gene. These results indicate that in the striatum, the enkephalin neurons are direct targets for dopamine liberated from mesostriatal neurons.

  18. Host factors that modify Plasmodium falciparum adhesion to endothelial receptors.

    Science.gov (United States)

    Mahamar, Almahamoudou; Attaher, Oumar; Swihart, Bruce; Barry, Amadou; Diarra, Bacary S; Kanoute, Moussa B; Cisse, Kadidia B; Dembele, Adama B; Keita, Sekouba; Gamain, Benoît; Gaoussou, Santara; Issiaka, Djibrilla; Dicko, Alassane; Duffy, Patrick E; Fried, Michal

    2017-10-24

    P. falciparum virulence is related to adhesion and sequestration of infected erythrocytes (IE) in deep vascular beds, but the endothelial receptors involved in severe malaria remain unclear. In the largest ever study of clinical isolates, we surveyed adhesion of freshly collected IE from children under 5 years of age in Mali to identify novel vascular receptors, and examined the effects of host age, hemoglobin type, blood group and severe malaria on levels of IE adhesion to a panel of endothelial receptors. Several novel molecules, including integrin α3β1, VE-cadherin, ICAM-2, junctional adhesion molecule-B (JAM-B), laminin, and cellular fibronectin, supported binding of IE from children. Severe malaria was not significantly associated with levels of IE adhesion to any of the 19 receptors. Hemoglobin AC, which reduces severe malaria risk, reduced IE binding to the receptors CD36 and integrin α5β1, while hemoglobin AS did not modify IE adhesion to any receptors. Blood groups A, AB and B significantly reduced IE binding to ICAM-1. Severe malaria risk varies with age, but age significantly impacted the level of IE binding to only a few receptors: IE binding to JAM-B decreased with age, while binding to CD36 and integrin α5β1 significantly increased with age.

  19. Flavivirus Entry Receptors: An Update

    Directory of Open Access Journals (Sweden)

    Manuel Perera-Lecoin

    2013-12-01

    Full Text Available Flaviviruses enter host cells by endocytosis initiated when the virus particles interact with cell surface receptors. The current model suggests that flaviviruses use at least two different sets of molecules for infectious entry: attachment factors that concentrate and/or recruit viruses on the cell surface and primary receptor(s that bind to virions and direct them to the endocytic pathway. Here, we present the currently available knowledge regarding the flavivirus receptors described so far with specific attention to C-type lectin receptors and the phosphatidylserine receptors, T-cell immunoglobulin and mucin domain (TIM and TYRO3, AXL and MER (TAM. Their role in flavivirus attachment and entry as well as their implication in the virus biology will be discussed in depth.

  20. Selectivity and specificity of sphingosine-1-phosphate receptor ligands: caveats and critical thinking in characterizing receptor-mediated effects.

    Science.gov (United States)

    Salomone, Salvatore; Waeber, Christian

    2011-01-01

    Receptors for sphingosine-1-phosphate (S1P) have been identified only recently. Their medicinal chemistry is therefore still in its infancy, and few selective agonists or antagonists are available. Furthermore, the selectivity of S1P receptor agonists or antagonists is not well established. JTE-013 and BML-241 (also known as CAY10444), used extensively as specific S1P(2) and S1P(3) receptors antagonists respectively, are cases in point. When analyzing S1P-induced vasoconstriction in mouse basilar artery, we observed that JTE-013 inhibited not only the effect of S1P, but also the effect of U46619, endothelin-1 or high KCl; JTE-013 strongly inhibited responses to S1P in S1P(2) receptor knockout mice. Similarly, BML-241 has been shown to inhibit increases in intracellular Ca(2+) concentration via P(2) receptor or α(1A)-adrenoceptor stimulation and α(1A)-adrenoceptor-mediated contraction of rat mesenteric artery, while it did not affect S1P(3)-mediated decrease of forskolin-induced cyclic AMP accumulation. Another putative S1P(1/3) receptor antagonist, VPC23019, does not inhibit S1P(3)-mediated vasoconstriction. With these examples in mind, we discuss caveats about relying on available pharmacological tools to characterize receptor subtypes.

  1. Selectivity and specificity of sphingosine-1-phosphate receptor ligands: caveats and critical thinking in characterizing receptor-mediated effects

    Directory of Open Access Journals (Sweden)

    Christian eWaeber

    2011-02-01

    Full Text Available Receptors for sphingosine-1-phosphate (S1P have been identified only recently. Their medicinal chemistry is therefore still in its infancy, and few selective agonists or antagonists are available. Furthermore, the selectivity of S1P receptor agonists or antagonists is not well established. JTE-013 and BML-241 (also known as CAY10444, used extensively as specific S1P2 and S1P3 receptors antagonists respectively, are cases in point. When analyzing S1P-induced vasoconstriction in mouse basilar artery, we observed that JTE-013 inhibited not only the effect of S1P, but also the effect of U46619, endothelin-1 or high KCl; JTE-013 strongly inhibited responses to S1P in S1P2 receptor knockout mice. Similarly, BML-241 has been shown to inhibit increases in intracellular Ca2+ concentration via P2 receptor or α1A-adrenoceptor stimulation and α1A-adrenoceptor-mediated contraction of rat mesenteric artery, while it did not affect S1P3-mediated decrease of forskolin-induced cyclic AMP accumulation. Another putative S1P1/3 receptor antagonist, VPC23019, does not inhibit S1P3-mediated vasoconstriction. With these examples in mind, we discuss caveats about relying on available pharmacological tools to characterize receptor subtypes.

  2. The NOAA Dataset Identifier Project

    Science.gov (United States)

    de la Beaujardiere, J.; Mccullough, H.; Casey, K. S.

    2013-12-01

    The US National Oceanic and Atmospheric Administration (NOAA) initiated a project in 2013 to assign persistent identifiers to datasets archived at NOAA and to create informational landing pages about those datasets. The goals of this project are to enable the citation of datasets used in products and results in order to help provide credit to data producers, to support traceability and reproducibility, and to enable tracking of data usage and impact. A secondary goal is to encourage the submission of datasets for long-term preservation, because only archived datasets will be eligible for a NOAA-issued identifier. A team was formed with representatives from the National Geophysical, Oceanographic, and Climatic Data Centers (NGDC, NODC, NCDC) to resolve questions including which identifier scheme to use (answer: Digital Object Identifier - DOI), whether or not to embed semantics in identifiers (no), the level of granularity at which to assign identifiers (as coarsely as reasonable), how to handle ongoing time-series data (do not break into chunks), creation mechanism for the landing page (stylesheet from formal metadata record preferred), and others. Decisions made and implementation experience gained will inform the writing of a Data Citation Procedural Directive to be issued by the Environmental Data Management Committee in 2014. Several identifiers have been issued as of July 2013, with more on the way. NOAA is now reporting the number as a metric to federal Open Government initiatives. This paper will provide further details and status of the project.

  3. Identification of hormone-interacting amino acid residues within the steroid-binding domain of the glucocorticoid receptor in relation to other steroid hormone receptors

    International Nuclear Information System (INIS)

    Carlstedt-Duke, J.; Stroemstedt, P.E.; Persson, B.; Cederlund, E.; Gustafsson, J.A.; Joernvall, H.

    1988-01-01

    Purified rat liver glucocorticoid receptor was covalently charged with [ 3 H]glucocorticoid by photoaffinity labeling (UV irradiation of [ 3 H]triamcinolone acetonide-glucocorticoid receptor) or affinity labeling (incubation with [ 3 H]dexamethasone mesylate). After labeling, separate samples of the denatured receptor were cleaved with trypsin (directly or after prior succinylation), chymotrypsin, and cyanogen bromide. Labeled residues in the peptides obtained were identified by radiosequence analysis. The peaks of radioactivity corresponded to Met-622 and Cys-754 after photoaffinity labeling with [ 3 H]triamcinolone acetonide and Cys-656 after affinity labeling with [ 3 H]dexamethasone mesylate. The labeled residues are all positioned within hydrophobic segments of the steroid-binding domain. The patterns of hydropathy and secondary structure for the glucocorticoid receptor are highly similar to those for the progestin receptor and similar but less so to those for the estrogen receptor and to those for c-erb A

  4. Identification of steroid-binding and phosphorylated sites within the glucocorticoid receptor

    International Nuclear Information System (INIS)

    Smith, L.I.

    1989-01-01

    The primary goal of these studies was to localize the steroid-binding and phosphorylated sites of the glucocorticoid receptor. The synthetic steroid, dexamethasone 21-mesylate (DM) forms a covalent thioether bond via the sulfhydryl group of a cysteine residue in the receptor. To determine the covalent site of attachment of this ligand, receptors in WEHI-7 mouse thymoma cells were labeled with [ 3 H]DM and purified with a monoclonal antibody. The receptor was completely digested with trypsin and a single peptide covalently labeled with steroid identified by reversed-phase HPLC. This peptide was analyzed by automated Edman degradation to determine the location of the steroid-labeled residue. A similar analysis was performed on an overlapping peptide produced by Staphylococcus aureus protease digestion. Analysis of tryptic peptides from receptors labeled with both [ 3 H]DM and L-[ 35 S]methionine indicated that this peptide contained methionine. These analyses, coupled with the published amino acid sequence of the receptor, identified Cysteine-644 in the steroid-binding domain of the mouse glucocorticoid receptor as the residue involved in covalent steroid-binding. A synthetic peptide representing amino acids 640-650 of the mouse receptor was prepared and analyzed to confirm the identification. These biochemical studies represent a direct demonstration of an amino acid important in receptor function. It has been proposed that the receptor functions through a phosphorylation-dephosphorylation cycle to explain the dependence of hormone binding capacity upon cellular ATP. The glucocorticoid receptor has been shown to be a phosphoprotein. As an initial step to identifying a role of phosphorylation in receptor action, phosphorylated sites within the functional domains of the protein were identified

  5. Ligand-independent Thrombopoietin Mutant Receptor Requires Cell Surface Localization for Endogenous Activity*

    OpenAIRE

    Marty, Caroline; Chaligné, Ronan; Lacout, Catherine; Constantinescu, Stefan N.; Vainchenker, William; Villeval, Jean-Luc

    2009-01-01

    The activating W515L mutation in the thrombopoietin receptor (MPL) has been identified in primary myelofibrosis and essential thrombocythemia. MPL belongs to a subset of the cytokine receptor superfamily that requires the JAK2 kinase for signaling. We examined whether the ligand-independent MPLW515L mutant could signal intracellularly. Addition of the endoplasmic reticulum (ER) retention KDEL sequence to the receptor C terminus efficiently locked MPLW515L within its na...

  6. Benzodiazepine receptor binding in vivo with (/sup 3/)-Ro 15-1788

    Energy Technology Data Exchange (ETDEWEB)

    Goeders, N.E.; Kuhar, M.J.

    1985-07-29

    In vivo benzodiazepine receptor binding has generally been studied by ex vivo techniques. In this investigation, the authors identify the conditions where (/sup 3/H)-Ro 15-1788 labels benzodiazepine receptors by true in vivo binding, i.e. where workable specific to nonspecific ratios are obtained in intact tissues without homogenization or washing. (/sup 3/H)-Flunitrazepam and (/sup 3/H)-clonazepam did not exhibit useful in vivo receptor binding. 39 references, 5 figures, 1 table.

  7. Adenosine Receptors and Wound Healing

    Directory of Open Access Journals (Sweden)

    Bruce N. Cronstein

    2004-01-01

    Full Text Available Recent studies have demonstrated that application of topical adenosine A2A receptor agonists promotes more rapid wound closure and clinical studies are currently underway to determine the utility of topical A2A adenosine receptor agonists in the therapy of diabetic foot ulcers. The effects of adenosine A2A receptors on the cells and tissues of healing wounds have only recently been explored. We review here the known effects of adenosine A2A receptor occupancy on the cells involved in wound healing.

  8. Virally encoded 7TM receptors

    DEFF Research Database (Denmark)

    Rosenkilde, M M; Waldhoer, M; Lüttichau, H R

    2001-01-01

    expression of this single gene in certain lymphocyte cell lineages leads to the development of lesions which are remarkably similar to Kaposi's sarcoma, a human herpesvirus 8 associated disease. Thus, this and other virally encoded 7TM receptors appear to be attractive future drug targets.......A number of herpes- and poxviruses encode 7TM G-protein coupled receptors most of which clearly are derived from their host chemokine system as well as induce high expression of certain 7TM receptors in the infected cells. The receptors appear to be exploited by the virus for either immune evasion...

  9. Adenosine receptor desensitization and trafficking.

    Science.gov (United States)

    Mundell, Stuart; Kelly, Eamonn

    2011-05-01

    As with the majority of G-protein-coupled receptors, all four of the adenosine receptor subtypes are known to undergo agonist-induced regulation in the form of desensitization and trafficking. These processes can limit the ability of adenosine receptors to couple to intracellular signalling pathways and thus reduce the ability of adenosine receptor agonists as well as endogenous adenosine to produce cellular responses. In addition, since adenosine receptors couple to multiple signalling pathways, these pathways may desensitize differentially, while the desensitization of one pathway could even trigger signalling via another. Thus, the overall picture of adenosine receptor regulation can be complex. For all adenosine receptor subtypes, there is evidence to implicate arrestins in agonist-induced desensitization and trafficking, but there is also evidence for other possible forms of regulation, including second messenger-dependent kinase regulation, heterologous effects involving G proteins, and the involvement of non-clathrin trafficking pathways such as caveolae. In this review, the evidence implicating these mechanisms is summarized for each adenosine receptor subtype, and we also discuss those issues of adenosine receptor regulation that remain to be resolved as well as likely directions for future research in this field. Copyright © 2010 Elsevier B.V. All rights reserved.

  10. Neuromedin B receptor in esophagus: evidence for subtypes of bombesin receptors

    International Nuclear Information System (INIS)

    Von Schrenck, T.; Heinz-Erian, P.; Moran, T.; Mantey, S.A.; Gardner, J.D.; Jensen, R.T.

    1989-01-01

    To identify receptors for bombesin-related peptides in the rat esophagus, we measured binding of 125I-Bolton-Hunter neuromedin B (125I-BH-neuromedin B) and 125I-[Tyr4]bombesin to tissue sections from the rat esophagus and compared the results with those for rat pancreas. Esophagus bound both tracers, whereas pancreas bound only 125I-[Tyr4]bombesin. In each tissue binding was saturable, dependent on pH, on time, and on temperature, reversible, and specific. Autoradiography demonstrated binding of both tracers only to the muscularis mucosae of the esophagus and binding of 125I-[Tyr4]bombesin diffusely over pancreatic acini. In the esophagus, the relative potencies for inhibition of binding of both tracers were as follows: neuromedin B greater than bombesin greater than GRP = neuromedin C; similar relative potencies were found for causing contraction of muscle strips from whole esophagus and from the isolated muscularis mucosae. In pancreas tissue sections and dispersed acini, the relative potencies for inhibition of binding of 125I-[Tyr4]bombesin were as follows: bombesin greater than GRP = neuromedin C much greater than neuromedin B. Similar relative potencies were found for stimulation of enzyme secretion from dispersed pancreatic acini. Computer analysis in both tissues demonstrated only a single binding site. The present study demonstrates that rat esophagus muscle possesses specific receptors for bombesin-related peptides. Furthermore, this study shows that the esophageal bombesin receptors represent a previously unidentified class of bombesin receptors in that they have a higher affinity for neuromedin B than for bombesin. In contrast, the pancreatic bombesin receptors have, like all other bombesin receptors described to date, a high affinity for bombesin, but low affinity for neuromedin B

  11. Proteomic profiling of human plasma exosomes identifies PPARγ as an exosome-associated protein

    International Nuclear Information System (INIS)

    Looze, Christopher; Yui, David; Leung, Lester; Ingham, Matthew; Kaler, Maryann; Yao, Xianglan; Wu, Wells W.; Shen Rongfong; Daniels, Mathew P.; Levine, Stewart J.

    2009-01-01

    Exosomes are nanovesicles that are released from cells as a mechanism of cell-free intercellular communication. Only a limited number of proteins have been identified from the plasma exosome proteome. Here, we developed a multi-step fractionation scheme incorporating gel exclusion chromatography, rate zonal centrifugation through continuous sucrose gradients, and high-speed centrifugation to purify exosomes from human plasma. Exosome-associated proteins were separated by SDS-PAGE and 66 proteins were identified by LC-MS/MS, which included both cellular and extracellular proteins. Furthermore, we identified and characterized peroxisome proliferator-activated receptor-γ (PPARγ), a nuclear receptor that regulates adipocyte differentiation and proliferation, as well as immune and inflammatory cell functions, as a novel component of plasma-derived exosomes. Given the important role of exosomes as intercellular messengers, the discovery of PPARγ as a component of human plasma exosomes identifies a potential new pathway for the paracrine transfer of nuclear receptors.

  12. The metabotropic glutamate receptors: structure, activation mechanism and pharmacology.

    Science.gov (United States)

    Pin, Jean-Philippe; Acher, Francine

    2002-06-01

    The metabotropic glutamate receptors are G-protein coupled receptors (GPCR) involved in the regulation of many synapses, including most glutamatergic fast excitatory synapses. Eight subtypes have been identified that can be classified into three groups. The molecular characterization of these receptors revealed proteins much more complex than any other GPCRs. They are composed of a Venus Flytrap (VFT) module where glutamate binds, connected to a heptahelical domain responsible for G-protein coupling. Recent data including the structure of the VFT module determined with and without glutamate, indicate that these receptors function as dimers. Moreover a number of intracellular proteins can regulate their targeting and transduction mechanism. Such structural features of mGlu receptors offer multiple possibilities for synthetic compounds to modulate their activity. In addition to agonists and competitive antagonists acting at the glutamate binding site, a number of non-competitive antagonists with inverse agonist activity, and positive allosteric modulators have been discovered. These later compounds share specific properties that make them good candidates for therapeutic applications. First, their non-amino acid structure makes them pass more easily the blood brain barrier. Second, they are much more selective than any other compound identified so far, being the first subtype selective molecules. Third, for the negative modulators, their non competitive mechanism of action makes them relatively unaffected by high concentrations of glutamate that may be present in disease states (e.g. stroke, epilepsy, neuropathic pain, etc.). Fourth, like the benzodiazepines acting at the GABA(A) receptors, the positive modulators offer a new way to increase the activity of these receptors in vivo, with a low risk of inducing their desensitization. The present review article focuses on the specific structural features of these receptors and highlights the various possibilities these

  13. Dynamic regulation of Drosophila nuclear receptor activity in vivo.

    Science.gov (United States)

    Palanker, Laura; Necakov, Aleksandar S; Sampson, Heidi M; Ni, Ruoyu; Hu, Chun; Thummel, Carl S; Krause, Henry M

    2006-09-01

    Nuclear receptors are a large family of transcription factors that play major roles in development, metamorphosis, metabolism and disease. To determine how, where and when nuclear receptors are regulated by small chemical ligands and/or protein partners, we have used a 'ligand sensor' system to visualize spatial activity patterns for each of the 18 Drosophila nuclear receptors in live developing animals. Transgenic lines were established that express the ligand binding domain of each nuclear receptor fused to the DNA-binding domain of yeast GAL4. When combined with a GAL4-responsive reporter gene, the fusion proteins show tissue- and stage-specific patterns of activation. We show that these responses accurately reflect the presence of endogenous and exogenously added hormone, and that they can be modulated by nuclear receptor partner proteins. The amnioserosa, yolk, midgut and fat body, which play major roles in lipid storage, metabolism and developmental timing, were identified as frequent sites of nuclear receptor activity. We also see dynamic changes in activation that are indicative of sweeping changes in ligand and/or co-factor production. The screening of a small compound library using this system identified the angular psoralen angelicin and the insect growth regulator fenoxycarb as activators of the Ultraspiracle (USP) ligand-binding domain. These results demonstrate the utility of this system for the functional dissection of nuclear receptor pathways and for the development of new receptor agonists and antagonists that can be used to modulate metabolism and disease and to develop more effective means of insect control.

  14. Axonal GABAA receptors.

    Science.gov (United States)

    Trigo, Federico F; Marty, Alain; Stell, Brandon M

    2008-09-01

    Type A GABA receptors (GABA(A)Rs) are well established as the main inhibitory receptors in the mature mammalian forebrain. In recent years, evidence has accumulated showing that GABA(A)Rs are prevalent not only in the somatodendritic compartment of CNS neurons, but also in their axonal compartment. Evidence for axonal GABA(A)Rs includes new immunohistochemical and immunogold data: direct recording from single axonal terminals; and effects of local applications of GABA(A)R modulators on action potential generation, on axonal calcium signalling, and on neurotransmitter release. Strikingly, whereas presynaptic GABA(A)Rs have long been considered inhibitory, the new studies in the mammalian brain mostly indicate an excitatory action. Depending on the neuron that is under study, axonal GABA(A)Rs can be activated by ambient GABA, by GABA spillover, or by an autocrine action, to increase either action potential firing and/or transmitter release. In certain neurons, the excitatory effects of axonal GABA(A)Rs persist into adulthood. Altogether, axonal GABA(A)Rs appear as potent neuronal modulators of the mammalian CNS.

  15. Possible Relevance of Receptor-Receptor Interactions between Viral- and Host-Coded Receptors for Viral-Induced Disease

    Directory of Open Access Journals (Sweden)

    Luigi F. Agnati

    2007-01-01

    Full Text Available It has been demonstrated that some viruses, such as the cytomegalovirus, code for G-protein coupled receptors not only to elude the immune system, but also to redirect cellular signaling in the receptor networks of the host cells. In view of the existence of receptor-receptor interactions, the hypothesis is introduced that these viral-coded receptors not only operate as constitutively active monomers, but also can affect other receptor function by interacting with receptors of the host cell. Furthermore, it is suggested that viruses could also insert not single receptors (monomers, but clusters of receptors (receptor mosaics, altering the cell metabolism in a profound way. The prevention of viral receptor-induced changes in host receptor networks may give rise to novel antiviral drugs that counteract viral-induced disease.

  16. Receptor studies in biological psychiatry

    International Nuclear Information System (INIS)

    Fujiwara, Yutaka

    1992-01-01

    Recent advances in the pharmacological treatment of endogenous psychosis have led to the development of biological studies in psychiatry. Studies on neurotransmitter receptors were reviewed in order to apply positron-emission tomograph (PET) for biological psychiatry. The dopamine (DA) hypothesis for schizophrenia was advanced on the basis of the observed effects of neuroleptics and methamphetamine, and DA(D 2 ) receptor supersensitivity measured by PET and receptor binding in the schizophrenic brain. The clinical potencies of neuroleptics for schizophrenia were correlated with their abilities to inhibit the D 2 receptor, and not other receptors. The σ receptor was expected to be a site of antipsychotic action. However, the potency of drugs action on it was not correlated with clinical efficacy. Haloperidol binds with high affinity to the σ receptor, which may mediate acute dystonia, an extrapyramidal side effect of neuroleptics. Behavioral and neurochemical changes induced by methamphetamine treatment were studied as an animal model of schizophrenia, and both a decrease of D 2 receptor density and an increase of DA release were detected. The monoamine hypothesis for manic-depressive psychosis was advanced on the basis of the effect of reserpine, monoamine oxidase inhibitor and antidepressants. 3 H-clonidine binding sites were increased in platelet membranes of depressive patients, 3 H-imipramine binding sites were decreased. The GABA A receptor is the target site for the action of anxiolytics and antiepileptics such as benzodiazepines and barbiturates. Recent developments in molecular biology techniques have revealed the structure of receptor proteins, which are classified into two receptor families, the G-protein coupled type (D 2 ) and the ion-channel type (GABA A ). (J.P.N.)

  17. Bombyx neuropeptide G protein-coupled receptor A7 is the third cognate receptor for short neuropeptide F from silkworm.

    Science.gov (United States)

    Ma, Qiang; Cao, Zheng; Yu, Yena; Yan, Lili; Zhang, Wenjuan; Shi, Ying; Zhou, Naiming; Huang, Haishan

    2017-12-15

    The short neuropeptide F (sNPF) neuropeptides, closely related to vertebrate neuropeptide Y (NPY), have been suggested to exert pleiotropic effects on many physiological processes in insects. In the silkworm ( Bombyx mori ) two orphan G protein-coupled receptors, Bombyx neuropeptide G protein-coupled receptor (BNGR) A10 and A11, have been identified as cognate receptors for sNPFs, but other sNPF receptors and their signaling mechanisms in B. mori remain unknown. Here, we cloned the full-length cDNA of the orphan receptor BNGR-A7 from the brain of B. mori larvae and identified it as a receptor for Bombyx sNPFs. Further characterization of signaling and internalization indicated that BNGR-A7, -A10, and -A11 are activated by direct interaction with synthetic Bombyx sNPF-1 and -3 peptides. This activation inhibited forskolin or adipokinetic hormone-induced adenylyl cyclase activity and intracellular Ca 2+ mobilization via a G i/o -dependent pathway. Upon activation by sNPFs, BNGR-A7, -A10, and -A11 evoked ERK1/2 phosphorylation and underwent internalization. On the basis of these findings, we designated the receptors BNGR-A7, -A10, and -A11 as Bommo -sNPFR-1, -2, and -3, respectively. Moreover, the results obtained with quantitative RT-PCR analysis revealed that the three Bombyx sNPF receptor subtypes exhibit differential spatial and temporal expression patterns, suggesting possible roles of sNPF signaling in the regulation of a wide range of biological processes. Our findings provide the first in-depth information on sNPF signaling for further elucidation of the roles of the Bombyx sNPF/sNPFR system in the regulation of physiological activities. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Liver X receptor α and farnesoid X receptor are major transcriptional regulators of OATP1B1.

    Science.gov (United States)

    Meyer Zu Schwabedissen, Henriette E; Böttcher, Kerstin; Chaudhry, Amarjit; Kroemer, Heyo K; Schuetz, Erin G; Kim, Richard B

    2010-11-01

    Organic anion transporting polypeptide 1B1 (OATP1B1) is a liver-enriched transporter involved in the hepatocellular uptake of many endogenous molecules and several structurally divergent drugs in clinical use. Although OATP1B1 coding region polymorphisms are known to make an impact on substrate drug disposition in humans, little is known regarding the mechanisms underlying the transcriptional regulation of this transporter. In this study, we note that messenger RNA (mRNA) expression of OATP1B1 in a large human liver bank exhibited marked interindividual variability that was not associated with coding region polymorphisms. Accordingly, we hypothesized that such variability in expression is reflective of nuclear receptor-mediated transcriptional regulation of this transporter. We tested prototypical ligands for the nuclear receptors pregnane X receptor (PXR), constitutive androstane receptor (CAR), liver X receptor (LXR) α, and farnesoid X receptor (FXR) in a human hepatoma-derived cell line and noted induction of OATP1B1 mRNA when the cells were treated with LXRα or FXR ligands. To confirm a direct role for LXRα and FXR to OATP1B1 expression, we performed detailed promoter analysis and cell-based reporter gene assays resulting in the identification of two functional FXR response elements and one LXRα response element. The direct interaction between nuclear receptors with the identified response elements was assessed using chromatin immunoprecipitation assays. Using isolated primary human hepatocytes, we show that LXRα or FXR agonists, but not PXR or CAR agonists, are capable of OATP1B1 induction. We note that OATP1B1 transcriptional regulation is under dual nuclear receptor control through the oxysterol sensing LXRα and the bile acid sensor FXR. Accordingly, the interplay between OATP1B1 and nuclear receptors may play an important and heretofore unrecognized role during cholestasis, drug-induced liver injury, and OATP1B1 induction-related drug interactions.

  19. Regulation of formyl peptide receptor binding to rabbit neutrophil plasma membranes. Use of monovalent cations, guanine nucleotides, and bacterial toxins to discriminate among different states of the receptor

    International Nuclear Information System (INIS)

    Feltner, D.E.; Marasco, W.A.

    1989-01-01

    The regulation by monovalent cations, guanine nucleotides, and bacterial toxins of [3H]FMLP binding to rabbit neutrophil plasma membranes was studied by using dissociation techniques to identify regulatory effects on separate receptor states. Under conditions of low receptor occupancy (1 nM [3H]FMLP) and in both Na+ and K+ buffers, dissociation is heterogenous, displaying two distinct, statistically significant off rates. [3H]FMLP binding was enhanced by substituting other monovalent cations for Na+. In particular, enhanced binding in the presence of K+ relative to Na+ was caused by additional binding to both rapidly and slowly dissociating receptors. Three receptor dissociation rates, two of which appear to correspond to the two affinity states detected in equilibrium binding studies, were defined by specific GTP and pertussis toxin (PT) treatments. Neither GTP, nor PT or cholera toxins (CT) had an effect on the rate of dissociation of [3H]FMLP from the rapidly dissociating form of the receptor. Both 100 microM GTP and PT treatments increased the percentage of rapidly dissociating receptors, correspondingly decreasing the percentage of slowly dissociating receptors. The observed changes in the rapidly and slowly dissociating receptors after GTP, PT, and CT treatments were caused by an absolute decrease in the amount of binding to the slowly dissociating receptors. However, complete inhibition of slowly dissociating receptor binding by GTP, PT, or both was never observed. Both GTP and PT treatments, but not CT treatment, increased by two-fold the rate of dissociation of 1 nM [3H]FMLP from the slowly dissociating form of the receptor, resulting in a third dissociation rate. Thus, slowly dissociating receptors comprise two different receptor states, a G protein-associated guanine nucleotide and PT-sensitive state and a guanine nucleotide-insensitive state

  20. Parameter trajectory analysis to identify treatment effects of pharmacological interventions.

    Directory of Open Access Journals (Sweden)

    Christian A Tiemann

    Full Text Available The field of medical systems biology aims to advance understanding of molecular mechanisms that drive disease progression and to translate this knowledge into therapies to effectively treat diseases. A challenging task is the investigation of long-term effects of a (pharmacological treatment, to establish its applicability and to identify potential side effects. We present a new modeling approach, called Analysis of Dynamic Adaptations in Parameter Trajectories (ADAPT, to analyze the long-term effects of a pharmacological intervention. A concept of time-dependent evolution of model parameters is introduced to study the dynamics of molecular adaptations. The progression of these adaptations is predicted by identifying necessary dynamic changes in the model parameters to describe the transition between experimental data obtained during different stages of the treatment. The trajectories provide insight in the affected underlying biological systems and identify the molecular events that should be studied in more detail to unravel the mechanistic basis of treatment outcome. Modulating effects caused by interactions with the proteome and transcriptome levels, which are often less well understood, can be captured by the time-dependent descriptions of the parameters. ADAPT was employed to identify metabolic adaptations induced upon pharmacological activation of the liver X receptor (LXR, a potential drug target to treat or prevent atherosclerosis. The trajectories were investigated to study the cascade of adaptations. This provided a counter-intuitive insight concerning the function of scavenger receptor class B1 (SR-B1, a receptor that facilitates the hepatic uptake of cholesterol. Although activation of LXR promotes cholesterol efflux and -excretion, our computational analysis showed that the hepatic capacity to clear cholesterol was reduced upon prolonged treatment. This prediction was confirmed experimentally by immunoblotting measurements of SR-B1

  1. Quantitative analysis of receptor imaging

    International Nuclear Information System (INIS)

    Fu Zhanli; Wang Rongfu

    2004-01-01

    Model-based methods for quantitative analysis of receptor imaging, including kinetic, graphical and equilibrium methods, are introduced in detail. Some technical problem facing quantitative analysis of receptor imaging, such as the correction for in vivo metabolism of the tracer and the radioactivity contribution from blood volume within ROI, and the estimation of the nondisplaceable ligand concentration, is also reviewed briefly

  2. Coronavirus spike-receptor interactions

    NARCIS (Netherlands)

    Mou, H.

    2015-01-01

    Coronaviruses cause important diseases in humans and animals. Coronavirus infection starts with the virus binding with its spike proteins to molecules present on the surface of host cells that act as receptors. This spike-receptor interaction is highly specific and determines the virus’ cell, tissue

  3. Regulation of Liver Energy Balance by the Nuclear Receptors Farnesoid X Receptor and Peroxisome Proliferator Activated Receptor α.

    Science.gov (United States)

    Kim, Kang Ho; Moore, David D

    2017-01-01

    The liver undergoes major changes in substrate utilization and metabolic output over the daily feeding and fasting cycle. These changes occur acutely in response to hormones such as insulin and glucagon, with rapid changes in signaling pathways mediated by protein phosphorylation and other post-translational modifications. They are also reflected in chronic alterations in gene expression in response to nutrient-sensitive transcription factors. Among these, the nuclear receptors farnesoid X receptor (FXR) and peroxisome proliferator activated receptor α (PPARα) provide an intriguing, coordinated response to maintain energy balance in the liver. FXR is activated in the fed state by bile acids returning to the liver, while PPARα is activated in the fasted state in response to the free fatty acids produced by adipocyte lipolysis or possibly other signals. Key Messages: Previous studies indicate that FXR and PPARα have opposing effects on each other's primary targets in key metabolic pathways including gluconeogenesis. Our more recent work shows that these 2 nuclear receptors coordinately regulate autophagy: FXR suppresses this pathway of nutrient and energy recovery, while PPARα activates it. Another recent study indicates that FXR activates the complement and coagulation pathway, while earlier studies identify this as a negative target of PPARα. Since secretion is a very energy- and nutrient-intensive process for hepatocytes, it is possible that FXR licenses it in the nutrient-rich fed state, while PPARα represses it to spare resources in the fasted state. Energy balance is a potential connection linking FXR and PPARα regulation of autophagy and secretion, 2 seemingly unrelated aspects of hepatocyte function. FXR and PPARα act coordinately to promote energy balance and homeostasis in the liver by regulating autophagy and potentially protein secretion. It is quite likely that their impact extends to additional pathways relevant to hepatic energy balance, and

  4. Untangling dopamine-adenosine receptor-receptor assembly in experimental parkinsonism in rats

    Directory of Open Access Journals (Sweden)

    Víctor Fernández-Dueñas

    2015-01-01

    Full Text Available Parkinson’s disease (PD is a dopaminergic-related pathology in which functioning of the basal ganglia is altered. It has been postulated that a direct receptor-receptor interaction – i.e. of dopamine D2 receptor (D2R with adenosine A2A receptor (A2AR (forming D2R-A2AR oligomers – finely regulates this brain area. Accordingly, elucidating whether the pathology prompts changes to these complexes could provide valuable information for the design of new PD therapies. Here, we first resolved a long-standing question concerning whether D2R-A2AR assembly occurs in native tissue: by means of different complementary experimental approaches (i.e. immunoelectron microscopy, proximity ligation assay and TR-FRET, we unambiguously identified native D2R-A2AR oligomers in rat striatum. Subsequently, we determined that, under pathological conditions (i.e. in a rat PD model, D2R-A2AR interaction was impaired. Collectively, these results provide definitive evidence for alteration of native D2R-A2AR oligomers in experimental parkinsonism, thus conferring the rationale for appropriate oligomer-based PD treatments.

  5. PKCζ regulates Notch receptor routing and activity in a Notch signaling-dependent manner

    NARCIS (Netherlands)

    Sjöqvist, M.; Antfolk, D.; Ferraris, S.; Rraklli, V.; Haga, C.; Antila, C.; Mutvei, A.; Imanishi, S.Y.; Holmberg, J.; Jin, S.; Eriksson, J.E.; Lendahl, U.; Sahlgren, C.M.

    Activation of Notch signaling requires intracellular routing of the receptor, but the mechanisms controlling the distinct steps in the routing process is poorly understood. We identify PKCζ as a key regulator of Notch receptor intracellular routing. When PKCζ was inhibited in the developing chick

  6. Oxime Ethers of (E)-11-Isonitrosostrychnine as Highly Potent Glycine Receptor Antagonists

    DEFF Research Database (Denmark)

    Mohsen, Amal M Y; Mandour, Yasmine M; Sarukhanyan, Edita

    2016-01-01

    of the crystal structure of the α3 glycine receptor indicated the same orientation of the strychnine core for all analogues. For the most potent oxime ethers, the ether substituent was accommodated in a lipophilic receptor binding pocket. The findings identify the oxime hydroxy group as a suitable attachment...

  7. Small-molecule agonists for the glucagon-like peptide 1 receptor

    DEFF Research Database (Denmark)

    Knudsen, Lotte Bjerre; Kiel, Dan; Teng, Min

    2007-01-01

    and independent agonists. Potency of GLP-1 was not changed by the allosteric agonists, but affinity of GLP-1 for the receptor was increased. The most potent compound identified stimulates glucose-dependent insulin release from normal mouse islets but, importantly, not from GLP-1 receptor knockout mice. Also...

  8. DNA Repair, Redox Regulation and Modulation of Estrogen Receptor Alpha Mediated Transcription

    Science.gov (United States)

    Curtis-Ducey, Carol Dianne

    2009-01-01

    Interaction of estrogen receptor [alpha] (ER[alpha]) with 17[beta]-estradiol (E[subscript 2]) facilitates binding of the receptor to estrogen response elements (EREs) in target genes, which in turn leads to recruitment of coregulatory proteins. To better understand how estrogen-responsive genes are regulated, our laboratory identified a number of…

  9. Estrogen-related receptor beta interacts with Oct4 to positively regulate Nanog gene expression

    NARCIS (Netherlands)

    D.L.C. van den Berg (Debbie); W. Zhang (Wensheng); A. Yates (Adam); M.P. Engelen (Erik); K. Takacs (Katalin); K. Bezstarosti (Karel); J.A.A. Demmers (Jeroen); I. Chambers (Ian); R.A. Poor (Raymond)

    2008-01-01

    textabstractEmbryonic stem (ES) cell self-renewal is regulated by transcription factors, including Oct4, Sox2, and Nanog. A number of additional transcriptional regulators of ES cell self-renewal have recently been identified, including the orphan nuclear receptor estrogen-related receptor beta

  10. Ligand binding and activation mechanism og the glucagon-like peptide-1 receptor

    DEFF Research Database (Denmark)

    Underwood, Christina Rye

    GLP-1R interacts with receptor agonists. The thesis includes four studies, which investigate different aspects of these interactions. The first study elucidates GLP-1 binding to the extracellular domain of GLP-1R (ECD) (Study I), whereas the second study identifies receptor domains important for small...

  11. Molecular cloning and functional expression of the first two specific insect myosuppressin receptors

    DEFF Research Database (Denmark)

    Egerod, Kristoffer; Reynisson, Eyjólfur; Hauser, Frank

    2003-01-01

    insect visceral muscles. Other tested Drosophila neuropeptides did not activate the two receptors. In addition to the two Drosophila myosuppressin receptors, we identified a sequence in the genomic database from the malaria mosquito Anopheles gambiae that also very likely codes for a myosuppressin...

  12. Neurobeachin regulates neurotransmitter receptor trafficking to synapses

    NARCIS (Netherlands)

    Nair, R.; Lauks, J.; Jung, S; Cooke, N.E.; de Wit, H.; Brose, N.; Kilimann, M.W.; Verhage, M.; Rhee, J.

    2013-01-01

    The surface density of neurotransmitter receptors at synapses is a key determinant of synaptic efficacy. Synaptic receptor accumulation is regulated by the transport, postsynaptic anchoring, and turnover of receptors, involving multiple trafficking, sorting, motor, and scaffold proteins. We found

  13. A Novel Mechanism of Androgen Receptor Action

    National Research Council Canada - National Science Library

    Roberts, Jr, Charles T

    2006-01-01

    .... Specifically, the authors had determined that the androgen receptor controls the expression of the cell-surface receptor for the hormone IGF-1 at the level of translation of the IGF-1 receptor mRNA...

  14. Toll-Like Receptors: Role in Dermatological Disease

    Directory of Open Access Journals (Sweden)

    Aswin Hari

    2010-01-01

    Full Text Available Toll-like receptors (TLRs are a class of conserved receptors that recognize pathogen-associated molecular patterns (PAMPs present in microbes. In humans, at least ten TLRs have been identified, and their recognition targets range from bacterial endotoxins to lipopeptides, DNA, dsRNA, ssRNA, fungal products, and several host factors. Of dermatological interest, these receptors are expressed on several skin cells including keratinocytes, melanocytes, and Langerhans cells. TLRs are essential in identifying microbial products and are known to link the innate and adaptive immune systems. Over the years, there have been significant advances in our understanding of TLRs in skin inflammation, cutaneous malignancies, and defence mechanisms. In this paper, we will describe the association between TLRs and various skin pathologies and discuss proposed TLR therapeutics.

  15. GABAA receptor-expressing neurons promote consumption in Drosophila melanogaster.

    Science.gov (United States)

    Cheung, Samantha K; Scott, Kristin

    2017-01-01

    Feeding decisions are highly plastic and bidirectionally regulated by neurons that either promote or inhibit feeding. In Drosophila melanogaster, recent studies have identified four GABAergic interneurons that act as critical brakes to prevent incessant feeding. These GABAergic neurons may inhibit target neurons that drive consumption. Here, we tested this hypothesis by examining GABA receptors and neurons that promote consumption. We find that Resistance to dieldrin (RDL), a GABAA type receptor, is required for proper control of ingestion. Knockdown of Rdl in a subset of neurons causes overconsumption of tastants. Acute activation of these neurons is sufficient to drive consumption of appetitive substances and non-appetitive substances and acute silencing of these neurons decreases consumption. Taken together, these studies identify GABAA receptor-expressing neurons that promote Drosophila ingestive behavior and provide insight into feeding regulation.

  16. Identifying tier one key suppliers.

    Science.gov (United States)

    Wicks, Steve

    2013-01-01

    In today's global marketplace, businesses are becoming increasingly reliant on suppliers for the provision of key processes, activities, products and services in support of their strategic business goals. The result is that now, more than ever, the failure of a key supplier has potential to damage reputation, productivity, compliance and financial performance seriously. Yet despite this, there is no recognised standard or guidance for identifying a tier one key supplier base and, up to now, there has been little or no research on how to do so effectively. This paper outlines the key findings of a BCI-sponsored research project to investigate good practice in identifying tier one key suppliers, and suggests a scalable framework process model and risk matrix tool to help businesses effectively identify their tier one key supplier base.

  17. Ligand-receptor Interactions by NMR Spectroscopy

    Directory of Open Access Journals (Sweden)

    Novak. P.

    2008-04-01

    Full Text Available Today NMR spectroscopy is a method of choice for elucidation of interactions between biomolecules and the potential ligands. Knowledge on these interactions is an essential prerequisite for the rational drug design. The most important contribution of NMR to drug design a few years ago was the 3D structure determination of proteins. Besides delivering the 3D structures of the free proteins as a raw material for the modeling studies on ligand binding, NMR can directly yield valuable experimental data on the biologically important protein-ligand complexes. In addition to X-ray diffraction, NMR spectroscopy can provide information on the internal protein dynamics ordynamics of intermolecular interactions. Changes in NMR parameters allow us to detect ("SAR by NMR" and quantitatively determine binding affinities (titration, diffusion NMR experiments, etc. of potential ligands. Also, it is possible to determine the binding site and conformations of ligands, receptors and receptor-ligand complexes with the help of NMR methods such as tr-NOESY. Epitopes or functional groups responsible for binding of ligands to the receptor can be identified by employing STD or WaterLOGSY experiments. In this review are described some of the most frequent NMR methods for the characterization of the interactions between biomolecules and ligands, together with their advantages and disadvantages.

  18. Phrenic motor neuron adenosine 2A receptors elicit phrenic motor facilitation.

    Science.gov (United States)

    Seven, Yasin B; Perim, Raphael R; Hobson, Orinda R; Simon, Alec K; Tadjalli, Arash; Mitchell, Gordon S

    2018-04-15

    Although adenosine 2A (A 2A ) receptor activation triggers specific cell signalling cascades, the ensuing physiological outcomes depend on the specific cell type expressing these receptors. Cervical spinal adenosine 2A (A 2A ) receptor activation elicits a prolonged facilitation in phrenic nerve activity, which was nearly abolished following intrapleural A 2A receptor siRNA injections. A 2A receptor siRNA injections selectively knocked down A 2A receptors in cholera toxin B-subunit-identified phrenic motor neurons, sparing cervical non-phrenic motor neurons. Collectively, our results support the hypothesis that phrenic motor neurons express the A 2A receptors relevant to A 2A receptor-induced phrenic motor facilitation. Upregulation of A 2A receptor expression in the phrenic motor neurons per se may potentially be a useful approach to increase phrenic motor neuron excitability in conditions such as spinal cord injury. Cervical spinal adenosine 2A (A 2A ) receptor activation elicits a prolonged increase in phrenic nerve activity, an effect known as phrenic motor facilitation (pMF). The specific cervical spinal cells expressing the relevant A 2A receptors for pMF are unknown. This is an important question since the physiological outcome of A 2A receptor activation is highly cell type specific. Thus, we tested the hypothesis that the relevant A 2A receptors for pMF are expressed in phrenic motor neurons per se versus non-phrenic neurons of the cervical spinal cord. A 2A receptor immunostaining significantly colocalized with NeuN-positive neurons (89 ± 2%). Intrapleural siRNA injections were used to selectively knock down A 2A receptors in cholera toxin B-subunit-labelled phrenic motor neurons. A 2A receptor knock-down was verified by a ∼45% decrease in A 2A receptor immunoreactivity within phrenic motor neurons versus non-targeting siRNAs (siNT; P phrenic motor neurons. In rats that were anaesthetized, subjected to neuromuscular blockade and ventilated, p

  19. Quantitative densitometry of neurotransmitter receptors

    International Nuclear Information System (INIS)

    Rainbow, T.C.; Bleisch, W.V.; Biegon, A.; McEwen, B.S.

    1982-01-01

    An autoradiographic procedure is described that allows the quantitative measurement of neurotransmitter receptors by optical density readings. Frozen brain sections are labeled in vitro with [ 3 H]ligands under conditions that maximize specific binding to neurotransmitter receptors. The labeled sections are then placed against the 3 H-sensitive LKB Ultrofilm to produce the autoradiograms. These autoradiograms resemble those produced by [ 14 C]deoxyglucose autoradiography and are suitable for quantitative analysis with a densitometer. Muscarinic cholinergic receptors in rat and zebra finch brain and 5-HT receptors in rat brain were visualized by this method. When the proper combination of ligand concentration and exposure time are used, the method provides quantitative information about the amount and affinity of neurotransmitter receptors in brain sections. This was established by comparisons of densitometric readings with parallel measurements made by scintillation counting of sections. (Auth.)

  20. Dopamine Receptors and Parkinson's Disease

    Directory of Open Access Journals (Sweden)

    Shin Hisahara

    2011-01-01

    Full Text Available Parkinson's disease (PD is a progressive extrapyramidal motor disorder. Pathologically, this disease is characterized by the selective dopaminergic (DAergic neuronal degeneration in the substantia nigra. Correcting the DA deficiency in PD with levodopa (L-dopa significantly attenuates the motor symptoms; however, its effectiveness often declines, and L-dopa-related adverse effects emerge after long-term treatment. Nowadays, DA receptor agonists are useful medication even regarded as first choice to delay the starting of L-dopa therapy. In advanced stage of PD, they are also used as adjunct therapy together with L-dopa. DA receptor agonists act by stimulation of presynaptic and postsynaptic DA receptors. Despite the usefulness, they could be causative drugs for valvulopathy and nonmotor complication such as DA dysregulation syndrome (DDS. In this paper, physiological characteristics of DA receptor familyare discussed. We also discuss the validity, benefits, and specific adverse effects of pharmaceutical DA receptor agonist.

  1. Football refereeing: Identifying innovative methods

    Directory of Open Access Journals (Sweden)

    Reza MohammadKazemi

    2014-08-01

    Full Text Available The aim of the present study is to identify the potentials innovation in football industry. Data were collected from 10 national and international referees, assistant referees and referees’ supervisors in Iran. In this study, technological innovations are identified that assist better refereeing performances. The analysis revealed a significant relationship between using new technologies and referees ‘performance. The results indicate that elite referees, assistant referees and supervisors agreed to use new technological innovations during the game. According to their comments, this kind of technology causes the referees’ performance development.

  2. Comparative gene expression profiling of in vitro differentiated megakaryocytes and erythroblasts identifies novel activatory and inhibitory platelet membrane proteins

    NARCIS (Netherlands)

    Macaulay, Iain C.; Tijssen, Marloes R.; Thijssen-Timmer, Daphne C.; Gusnanto, Arief; Steward, Michael; Burns, Philippa; Langford, Cordelia F.; Ellis, Peter D.; Dudbridge, Frank; Zwaginga, Jaap-Jan; Watkins, Nicholas A.; van der Schoot, C. Ellen; Ouwehand, Willem H.

    2007-01-01

    To identify previously unknown platelet receptors we compared the transcriptomes of in vitro differentiated megakaryocytes (MKs) and erythroblasts (EBs). RNA was obtained from purified, biologically paired MK and EB cultures and compared using cDNA microarrays. Bioinformatical analysis of

  3. Molecular characterization of opioid receptors

    Energy Technology Data Exchange (ETDEWEB)

    Howard, A.D.

    1986-01-01

    The aim of this research was to purify and characterize active opioid receptors and elucidate molecular aspects of opioid receptor heterogeneity. Purification to apparent homogeneity of an opioid binding protein from bovine caudate was achieved by solubilization in the non-ionic detergent, digitonin, followed by sequential chromatography on the opiate affinity matrix, ..beta..-naltrexylethylenediamine-CH-Sepharose 4B, and on the lectine affinity matrix, wheat germ agglutinin-agarose. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE) followed by autoradiography revealed that radioiodinated purified receptor gave a single band. Purified receptor preparations showed a specific activity of 12,000-15,000 fmol of opiate bound per mg of protein. Radioiodinated human beta-endorphin (/sup 125/I-beta-end/sub H/) was used as a probe to investigate the ligand binding subunits of mu and delta opioid receptors. /sup 125/I-beta-end/sub H/ was shown to bind to a variety of opioid receptor-containing tissues with high affinity and specificity with preference for mu and delta sites, and with little, if any, binding to kappa sites. Affinity crosslinking techniques were employed to covalently link /sup 125/I-beta-end/sub H/ to opioid receptors, utilizing derivatives of bis-succinimidyl esters that are bifunctional crosslinkers with specificities for amino and sulfhydryl groups. This, and competition experiments with high type-selective ligands, permitted the assignment of two labeled peptides to their receptor types, namely a peptide of M/sub r/ = 65,000 for mu receptors and one of M/sub r/ = 53,000 for delta receptors.

  4. Species differences in the localization and number of CNS beta adrenergic receptors: Rat versus guinea pig

    International Nuclear Information System (INIS)

    Booze, R.M.; Crisostomo, E.A.; Davis, J.N.

    1989-01-01

    The localization and number of beta adrenergic receptors were directly compared in the brains of rats and guinea pigs. The time course of association and saturability of [125I]cyanopindolol (CYP) binding to slide-mounted tissue sections was similar in rats (Kd = 17 pM) and guinea pigs (Kd = 20 pM). The beta-1 and beta-2 receptor subtypes were examined through the use of highly selective unlabeled receptor antagonists, ICI 118,551 (50 nM) and ICI 89,406 (70 nM). Dramatic species differences between rats and guinea pigs were observed in the neuroanatomical regional localization of the beta adrenergic receptor subtypes. For example, in the thalamus prominent beta-1 and beta-2 receptor populations were identified in the rat; however, the entire thalamus of the guinea pig had few, if any, beta adrenergic receptors of either subtype. Hippocampal area CA1 had high levels of beta-2 adrenergic receptors in both rats and guinea pigs but was accompanied by a widespread distribution of beta-2 adrenergic receptors only in rats. Quantitative autoradiographic analyses of 25 selected neuroanatomical regions (1) confirmed the qualitative differences in CNS beta adrenergic receptor localization, (2) determined that guinea pigs had significantly lower levels of beta adrenergic receptors than rats and (3) indicated a differential pattern of receptor subtypes between the two species. Knowledge of species differences in receptor patterns may be useful in designing effective experiments as well as in exploring the relationships between receptor and innervation patterns. Collectively, these data suggest caution be used in extrapolation of the relationships of neurotransmitters and receptors from studies of a single species

  5. SOCIODEMOGRAPHIC DATA USED FOR IDENTIFYING ...

    Science.gov (United States)

    Due to unique social and demographic characteristics, various segments of the population may experience exposures different from those of the general population, which, in many cases, may be greater. When risk assessments do not characterize subsets of the general population, the populations that may experience the greatest risk remain unidentified. When such populations are not identified, the social and demographic data relevant to these populations is not considered when preparing exposure estimates, which can underestimate exposure and risk estimates for at-risk populations. Thus, it is necessary for risk or exposure assessors characterizing a diverse population, to first identify and then enumerate certain groups within the general population who are at risk for greater contaminant exposures. The document entitled Sociodemographic Data Used for Identifying Potentially Highly Exposed Populations (also referred to as the Highly Exposed Populations document), assists assessors in identifying and enumerating potentially highly exposed populations. This document presents data relating to factors which potentially impact an individual or group's exposure to environmental contaminants based on activity patterns (how time is spent), microenvironments (locations where time is spent), and other socio-demographic data such as age, gender, race and economic status. Populations potentially more exposed to various chemicals of concern, relative to the general population

  6. SNP interaction pattern identifier (SIPI)

    DEFF Research Database (Denmark)

    Lin, Hui Yi; Chen, Dung Tsa; Huang, Po Yu

    2017-01-01

    Motivation: Testing SNP-SNP interactions is considered as a key for overcoming bottlenecks of genetic association studies. However, related statistical methods for testing SNP-SNP interactions are underdeveloped. Results: We propose the SNP Interaction Pattern Identifier (SIPI), which tests 45...

  7. Identifying the Gifted Child Humorist.

    Science.gov (United States)

    Fern, Tami L.

    1991-01-01

    This study attempted to identify gifted child humorists among 1,204 children in grades 3-6. Final identification of 13 gifted child humorists was determined through application of such criteria as funniness, originality, and exemplary performance or product. The influence of intelligence, development, social factors, sex differences, family…

  8. Identifying high-risk medication

    DEFF Research Database (Denmark)

    Sædder, Eva; Brock, Birgitte; Nielsen, Lars Peter

    2014-01-01

    salicylic acid, and beta-blockers; 30 drugs or drug classes caused 82 % of all serious MEs. The top ten drugs involved in fatal events accounted for 73 % of all drugs identified. CONCLUSION: Increasing focus on seven drugs/drug classes can potentially reduce hospitalizations, extended hospitalizations...

  9. Ghrelin receptor inverse agonists: identification of an active peptide core and its interaction epitopes on the receptor

    DEFF Research Database (Denmark)

    Holst, Birgitte; Lang, Manja; Brandt, Erik

    2006-01-01

    [D-Arg1,D-Phe5,D-Trp7,9,Leu11]Substance P functions as a low-potency antagonist but a high-potency full inverse agonist on the ghrelin receptor. Through a systematic deletion and substitution analysis of this peptide, the C-terminal carboxyamidated pentapeptide wFwLX was identified as the core...... structure, which itself displayed relatively low inverse agonist potency. Mutational analysis at 17 selected positions in the main ligand-binding crevice of the ghrelin receptor demonstrated that ghrelin apparently interacts only with residues in the middle part of the pocket [i.e., between transmembrane...... upon both AspII:20 and GluIII:09. The identified pharmacophore can possibly serve as the basis for targeted discovery of also nonpeptide inverse agonists for the ghrelin receptor....

  10. Potential cellular receptors involved in hepatitis C virus entry into cells

    Directory of Open Access Journals (Sweden)

    Muellhaupt Beat

    2005-04-01

    Full Text Available Abstract Hepatitis C virus (HCV infects hepatocytes and leads to permanent, severe liver damage. Since the genomic sequence of HCV was determined, progress has been made towards understanding the functions of the HCV-encoded proteins and identifying the cellular receptor(s responsible for adsorption and penetration of the virus particle into the target cells. Several cellular receptors for HCV have been proposed, all of which are associated with lipid and lipoprotein metabolism. This article reviews the cellular receptors for HCV and suggests a general model for HCV entry into cells, in which lipoproteins play a crucial role.

  11. Cysteinyl-Leukotriene Receptors and Cellular Signals

    Directory of Open Access Journals (Sweden)

    G. Enrico Rovati

    2007-01-01

    Full Text Available Cysteinyl-leukotrienes (cysteinyl-LTs exert a range of proinflammatory effects, such as constriction of airways and vascular smooth muscle, increase of endothelial cell permeability leading to plasma exudation and edema, and enhanced mucus secretion. They have proved to be important mediators in asthma, allergic rhinitis, and other inflammatory conditions, including cardiovascular diseases, cancer, atopic dermatitis, and urticaria. The classification into subtypes of the cysteinyl-LT receptors (CysLTRs was based initially on binding and functional data, obtained using the natural agonists and a wide range of antagonists. CysLTRs have proved remarkably resistant to cloning. However, in 1999 and 2000, the CysLT1R and CysLT2R were successfully cloned and both shown to be members of the G-protein coupled receptors (GPCRs superfamily. Molecular cloning has confirmed most of the previous pharmacological characterization and identified distinct expression patterns only partially overlapping. Recombinant CysLTRs couple to the Gq/11 pathway that modulates inositol phospholipids hydrolysis and calcium mobilization, whereas in native systems, they often activate a pertussis toxin-insensitive Gi/o-protein, or are coupled promiscuously to both G-proteins. Interestingly, recent data provide evidence for the existence of an additional receptor subtype that seems to respond to both cysteinyl-LTs and uracil nucleosides, and of an intracellular pool of CysLTRs that may have roles different from those of plasma membrane receptors. Finally, a cross-talk between the cysteinyl-LT and the purine systems is being delineated. This review will summarize recent data derived from studies on the molecular and cellular pharmacology of CysLTRs.

  12. Angiotensin receptors in Dupuytren's disease: a target for pharmacological treatment?

    Science.gov (United States)

    Stephen, Christopher; Touil, Leila; Vaiude, Partha; Singh, Jaipaul; McKirdy, Stuart

    2018-02-01

    Attempts at the pharmacological treatment of Dupuytren's disease have so far been unsuccessful, and the disease is not yet fully understood on a cellular level. The Renin-Angiotensin System has long been understood to play a circulating hormonal role. However, there is much evidence showing Angiotensin II to play a local role in wound healing and fibrosis, with ACE inhibitors being widely used as an anti-fibrotic agent in renal and cardiac disease. This study was designed to investigate the presence of Angiotensin II receptors 1 (AT1) and 2 (AT2) in Dupuytren's tissue to form a basis for further study into the pharmacological treatment of this condition. Tissue was harvested from 11 patients undergoing surgery for Dupuytren's disease. Each specimen was processed into frozen sections and immunostaining was employed to identify AT1 and AT2 receptors. Immunostaining for AT1 receptors was mildly positive in one patient and negative in all the remaining patients. However, all specimens stained extensively for AT2 receptors. This suggests that the expression of AT2 receptors is more prominent than AT1 receptors in Dupuytren's disease. These findings have opened a new avenue for future research involving ACE inhibitors, AT2 agonists, and AT2 antagonists in Dupuytren's disease.

  13. Distributed Persistent Identifiers System Design

    Directory of Open Access Journals (Sweden)

    Pavel Golodoniuc

    2017-06-01

    Full Text Available The need to identify both digital and physical objects is ubiquitous in our society. Past and present persistent identifier (PID systems, of which there is a great variety in terms of technical and social implementation, have evolved with the advent of the Internet, which has allowed for globally unique and globally resolvable identifiers. PID systems have, by in large, catered for identifier uniqueness, integrity, and persistence, regardless of the identifier’s application domain. Trustworthiness of these systems has been measured by the criteria first defined by Bütikofer (2009 and further elaborated by Golodoniuc 'et al'. (2016 and Car 'et al'. (2017. Since many PID systems have been largely conceived and developed by a single organisation they faced challenges for widespread adoption and, most importantly, the ability to survive change of technology. We believe that a cause of PID systems that were once successful fading away is the centralisation of support infrastructure – both organisational and computing and data storage systems. In this paper, we propose a PID system design that implements the pillars of a trustworthy system – ensuring identifiers’ independence of any particular technology or organisation, implementation of core PID system functions, separation from data delivery, and enabling the system to adapt for future change. We propose decentralisation at all levels — persistent identifiers and information objects registration, resolution, and data delivery — using Distributed Hash Tables and traditional peer-to-peer networks with information replication and caching mechanisms, thus eliminating the need for a central PID data store. This will increase overall system fault tolerance thus ensuring its trustworthiness. We also discuss important aspects of the distributed system’s governance, such as the notion of the authoritative source and data integrity

  14. Principles of agonist recognition in Cys-loop receptors

    DEFF Research Database (Denmark)

    Lynagh, Timothy Peter; Pless, Stephan Alexander

    2014-01-01

    , functional studies, and X-ray crystallography experiments identified the extracellular interface of adjacent subunits as the principal site of agonist binding. The question of how subtle differences at and around agonist-binding sites of different Cys-loop receptors can accommodate transmitters as chemically...

  15. Effectoromics-based identification of cell surface receptors in potato

    NARCIS (Netherlands)

    Domazakis, Emmanouil; Lin, Xiao; Aguilera-Galvez, Carolina; Wouters, Doret; Bijsterbosch, Gerard; Wolters, Pieter J.; Vleeshouwers, Vivianne G.A.A.

    2017-01-01

    In modern resistance breeding, effectors have emerged as tools for accelerating and improving the identification of immune receptors. Effector-assisted breeding was pioneered for identifying resistance genes (R genes) against Phytophthora infestans in potato (Solanum tuberosum). Here we show that

  16. The diversity of abnormal hormone receptors in adrenal Cushing's syndrome allows novel pharmacological therapies

    Directory of Open Access Journals (Sweden)

    Lacroix A.

    2000-01-01

    Full Text Available Recent studies from several groups have indicated that abnormal or ectopic expression and function of adrenal receptors for various hormones may regulate cortisol production in ACTH-independent hypercortisolism. Gastric inhibitory polypeptide (GIP-dependent Cushing's syndrome has been described in patients with either unilateral adenoma or bilateral macronodular adrenal hyperplasia; this syndrome results from the large adrenal overexpression of the GIP receptor without any activating mutation. We have conducted a systematic in vivo evaluation of patients with adrenal Cushing's syndrome in order to identify the presence of abnormal hormone receptors. In macronodular adrenal hyperplasia, we have identified, in addition to GIP-dependent Cushing's syndrome, other patients in whom cortisol production was regulated abnormally by vasopressin, ß-adrenergic receptor agonists, hCG/LH, or serotonin 5HT-4 receptor agonists. In patients with unilateral adrenal adenoma, the abnormal expression or function of GIP or vasopressin receptor has been found, but the presence of ectopic or abnormal hormone receptors appears to be less prevalent than in macronodular adrenal hyperplasia. The identification of the presence of an abnormal adrenal receptor offers the possibility of a new pharmacological approach to control hypercortisolism by suppressing the endogenous ligands or by using specific antagonists for the abnormal receptors.

  17. Stargazin Modulation of AMPA Receptors

    Directory of Open Access Journals (Sweden)

    Sana A. Shaikh

    2016-10-01

    Full Text Available Fast excitatory synaptic signaling in the mammalian brain is mediated by AMPA-type ionotropic glutamate receptors. In neurons, AMPA receptors co-assemble with auxiliary proteins, such as stargazin, which can markedly alter receptor trafficking and gating. Here, we used luminescence resonance energy transfer measurements to map distances between the full-length, functional AMPA receptor and stargazin expressed in HEK293 cells and to determine the ensemble structural changes in the receptor due to stargazin. In addition, we used single-molecule fluorescence resonance energy transfer to study the structural and conformational distribution of the receptor and how this distribution is affected by stargazin. Our nanopositioning data place stargazin below the AMPA receptor ligand-binding domain, where it is well poised to act as a scaffold to facilitate the long-range conformational selection observations seen in single-molecule experiments. These data support a model of stargazin acting to stabilize or select conformational states that favor activation.

  18. Radioiodinated ligands for dopamine receptors

    International Nuclear Information System (INIS)

    Kung, H.F.

    1994-01-01

    The dopamine receptor system is important for normal brain function; it is also the apparent action site for various neuroleptic drugs for the treatment of schizophrenia and other metal disorders. In the past few years radioiodinated ligands for single photon emission tomography (SPECT) have been successfully developed and tested in humans: [ 123 I]TISCH for D1 dopamine receptors; [ 123 I]IBZM, epidepride, IBF and FIDA2, four iodobenzamide derivatives, for D2/D3 dopamine receptors. In addition, [ 123 I]β-CIT (RTI-55) and IPT, cocaine derivatives, for the dopamine reuptake site are potentially useful for diagnosis of loss of dopamine neurons. The first iodinated ligand, (R)trans-7-OH-PIPAT, for D3 dopamine receptors, was synthesized and characterized with cloned cell lines (Spodoptera frugiperda, Sf9) expressing the D2 and D3 dopamine receptors and with rat basal forebrain membrane preparations. Most of the known iodobenzamides displayed similar potency in binding to both D2 and D3 dopamine receptors expressed in the cell lines. Initial studies appear to suggest that by fine tuning the structures it may be possible to develop agents specific for D2 and D3 dopamine receptors. It is important to investigate D2/D3 selectivity for this series of potent ligands

  19. Labeled receptor ligands for spect

    International Nuclear Information System (INIS)

    Kung, H.F.

    1989-01-01

    Receptor specific imaging agents for single photon emission computed tomography (SPECT) can potentially be useful in the understanding of basic biochemistry and pharmacology of receptors. SPECT images may also provide tools for evaluation of density and binding kinetics of a specific receptor, information important for diagnosis and patient management. Basic requirements for receptor imaging agents are: (a) they are labeled with short-lived isotopes, (b) they show high selectivity and specific uptake, (c) they exhibit high target/background ratio, and (d) they can be modeled to obtain quantitative information. Several good examples of CNS receptor specific ligands labeled with I-123 have been developed, including iodoQNB, iodoestrogen iodobenzadiazepine, iodobenazepine, iodobenzamides for muscarinic, estrogen benzadiazepine, D-1 and D-2 dopamine receptors. With the advent of newer and faster SPECT imaging devices, it may be feasible to quantitate the receptor density by in vivo imaging techniques. These new brain imaging agents can provide unique diagnostic information, which may not be available through other imaging modalities, such as CT and MRI

  20. The Pseudo signal peptide of the corticotropin-releasing factor receptor type 2A prevents receptor oligomerization.

    Science.gov (United States)

    Teichmann, Anke; Rutz, Claudia; Kreuchwig, Annika; Krause, Gerd; Wiesner, Burkhard; Schülein, Ralf

    2012-08-03

    N-terminal signal peptides mediate the interaction of native proteins with the translocon complex of the endoplasmic reticulum membrane and are cleaved off during early protein biogenesis. The corticotropin-releasing factor receptor type 2a (CRF(2(a))R) possesses an N-terminal pseudo signal peptide, which represents a so far unique domain within the large protein family of G protein-coupled receptors (GPCRs). In contrast to a conventional signal peptide, the pseudo signal peptide remains uncleaved and consequently forms a hydrophobic extension at the N terminus of the receptor. The functional consequence of the presence of the pseudo signal peptide is not understood. Here, we have analyzed the significance of this domain for receptor dimerization/oligomerization in detail. To this end, we took the CRF(2(a))R and the homologous corticotropin-releasing factor receptor type 1 (CRF(1)R) possessing a conventional cleaved signal peptide and conducted signal peptide exchange experiments. Using single cell and single molecule imaging methods (fluorescence resonance energy transfer and fluorescence cross-correlation spectroscopy, respectively) as well as biochemical experiments, we obtained two novel findings; we could show that (i) the CRF(2(a))R is expressed exclusively as a monomer, and (ii) the presence of the pseudo signal peptide prevents its oligomerization. Thus, we have identified a novel functional domain within the GPCR protein family, which plays a role in receptor oligomerization and which may be useful to study the functional significance of this process in general.

  1. Small Molecule Drug Discovery at the Glucagon-Like Peptide-1 Receptor

    Directory of Open Access Journals (Sweden)

    Francis S. Willard

    2012-01-01

    Full Text Available The therapeutic success of peptide glucagon-like peptide-1 (GLP-1 receptor agonists for the treatment of type 2 diabetes mellitus has inspired discovery efforts aimed at developing orally available small molecule GLP-1 receptor agonists. Although the GLP-1 receptor is a member of the structurally complex class B1 family of GPCRs, in recent years, a diverse array of orthosteric and allosteric nonpeptide ligands has been reported. These compounds include antagonists, agonists, and positive allosteric modulators with intrinsic efficacy. In this paper, a comprehensive review of currently disclosed small molecule GLP-1 receptor ligands is presented. In addition, examples of “ligand bias” and “probe dependency” for the GLP-1 receptor are discussed; these emerging concepts may influence further optimization of known molecules or persuade designs of expanded screening strategies to identify novel chemical starting points for GLP-1 receptor drug discovery.

  2. Functional polymorphisms in the P2X7 receptor gene are associated with osteoporosis

    DEFF Research Database (Denmark)

    Husted, L B; Harsløf, T; Stenkjær, L

    2013-01-01

    variant allele, which has been associated with increased receptor function in monocytes, was associated with increased total hip BMD in women. With the exception of His155Tyr for which we found conflicting results in men and women, our results are consistent with the phenotype of the knockout mouse......UNLABELLED: The P2X(7) receptor is an ATP-gated cation channel. We investigated the effect of both loss-of-function and gain-of-function polymorphisms in the P2X(7) receptor gene on BMD and risk of vertebral fractures and found that five polymorphisms and haplotypes containing three...... of these polymorphisms were associated with BMD and fracture risk. INTRODUCTION: The P2X(7) receptor is an ATP-gated cation channel. P2X(7) receptor knockout mice have reduced total bone mineral content, and because several functional polymorphisms have been identified in the human P2X(7) receptor gene, we wanted...

  3. ORCID: Author Identifiers for Librarians

    Directory of Open Access Journals (Sweden)

    Robyn B. Reed

    2017-10-01

    Full Text Available Generating accurate publication lists by researchers can be challenging when faced with scholars who have common names or who have published under name variations. This article describes ORCID and the goal of generating author identifiers for scholars to connect their research outputs. Included are the reasons for having author identifiers as well as the types of information within individual profiles. This article includes information on how academic libraries are playing a role with ORCID initiatives as well as describing how publishers, institutions, and funders are employing ORCID in their workflows. Highlighted is material on academic institutions in Pennsylvania using ORCID. The purpose of the article is to provide an overview of ORCID and its uses to inform librarians about this important initiative.

  4. Device for identifying fuel assembly

    International Nuclear Information System (INIS)

    Imai, Tetsuo; Miyazawa, Tatsuo.

    1982-01-01

    Purpose: To accurately identify a symbol printed on a hanging tool at the upper part of a fuel assembly. Constitution: Optical fibers are bundled to prepare a detector which is disposed at a predetermined position on a hanging tool. This position is set by a guide. Thus, the light emitted from an illumination lamp arrives at the bottom of a groove printed on the upper surface of the tool, and is divided into a weak light reflected upwardly and a strong light reflected on the surface lower than the groove. When these lights are received by the optical fibers, the fibers corresponding to the grooved position become dark, and the fibers corresponding to the ungrooved position become bright. Since the fuel assembly is identified by the dark and bright of the optical fibers as symbols, different machining can be performed every fuel assembly on the upper surface of the tool. (Yoshihara, H.)

  5. Identifying patient risks during hospitalization

    Directory of Open Access Journals (Sweden)

    Lucélia Ferreira Lima

    2008-12-01

    Full Text Available Objective: To identify the risks reported at a public institution andto know the main patient risks from the nursing staff point of view.Methods: A retrospective, descriptive and exploratory study. Thesurvey was developed at a hospital in the city of Taboão da Serra, SãoPaulo, Brazil. The study included all nurses working in care areas whoagreed to participate in the study. At the same time, sentinel eventsoccurring in the period from July 2006 to July 2007 were identified.Results: There were 440 sentinel events reported, and the main risksincluded patient falls, medication errors and pressure ulcers. Sixty-fivenurses were interviewed. They also reported patient falls, medicationerrors and pressure ulcers as the main risks. Conclusions: Riskassessment and implementation of effective preventive actions arenecessary to ensure patient’s safety. Involvement of a multidisciplinaryteam is one of the steps for a successful process.

  6. Identifying High Performance ERP Projects

    OpenAIRE

    Stensrud, Erik; Myrtveit, Ingunn

    2002-01-01

    Learning from high performance projects is crucial for software process improvement. Therefore, we need to identify outstanding projects that may serve as role models. It is common to measure productivity as an indicator of performance. It is vital that productivity measurements deal correctly with variable returns to scale and multivariate data. Software projects generally exhibit variable returns to scale, and the output from ERP projects is multivariate. We propose to use Data Envelopment ...

  7. Conformational transitions and interactions underlying the function of membrane embedded receptor protein kinases.

    Science.gov (United States)

    Bocharov, Eduard V; Sharonov, Georgy V; Bocharova, Olga V; Pavlov, Konstantin V

    2017-09-01

    Among membrane receptors, the single-span receptor protein kinases occupy a broad but specific functional niche determined by distinctive features of the underlying transmembrane signaling mechanisms that are briefly overviewed on the basis of some of the most representative examples, followed by a more detailed discussion of several hierarchical levels of organization and interactions involved. All these levels, including single-molecule interactions (e.g., dimerization, liganding, chemical modifications), local processes (e.g. lipid membrane perturbations, cytoskeletal interactions), and larger scale phenomena (e.g., effects of membrane surface shape or electrochemical potential gradients) appear to be closely integrated to achieve the observed diversity of the receptor functioning. Different species of receptor protein kinases meet their specific functional demands through different structural features defining their responses to stimulation, but certain common patterns exist. Signaling by receptor protein kinases is typically associated with the receptor dimerization and clustering, ligand-induced rearrangements of receptor domains through allosteric conformational transitions with involvement of lipids, release of the sequestered lipids, restriction of receptor diffusion, cytoskeleton and membrane shape remodeling. Understanding of complexity and continuity of the signaling processes can help identifying currently neglected opportunities for influencing the receptor signaling with potential therapeutic implications. This article is part of a Special Issue entitled: Interactions between membrane receptors in cellular membranes edited by Kalina Hristova. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Identification of novel selective V2 receptor non-peptide agonists.

    Science.gov (United States)

    Del Tredici, Andria L; Vanover, Kim E; Knapp, Anne E; Bertozzi, Sine M; Nash, Norman R; Burstein, Ethan S; Lameh, Jelveh; Currier, Erika A; Davis, Robert E; Brann, Mark R; Mohell, Nina; Olsson, Roger; Piu, Fabrice

    2008-10-30

    Peptides with agonist activity at the vasopressin V(2) receptor are used clinically to treat fluid homeostasis disorders such as polyuria and central diabetes insipidus. Of these peptides, the most commonly used is desmopressin, which displays poor bioavailability as well as potent activity at the V(1b) receptor, with possible stress-related adverse effects. Thus, there is a strong need for the development of small molecule chemistries with selective V(2) receptor agonist activity. Using the functional cell-based assay Receptor Selection and Amplification Technology (R-SAT((R))), a screening effort identified three small molecule chemotypes (AC-94544, AC-88324, and AC-110484) with selective agonist activity at the V(2) receptor. One of these compounds, AC-94544, displayed over 180-fold selectivity at the V(2) receptor compared to related vasopressin and oxytocin receptors and no activity at 28 other G protein-coupled receptors (GPCRs). All three compounds also showed partial agonist activity at the V(2) receptor in a cAMP accumulation assay. In addition, in a rat model of central diabetes insipidus, AC-94544 was able to significantly reduce urine output in a dose-dependent manner. Thus, AC-94544, AC-88324, and AC-110484 represent novel opportunities for the treatment of disorders associated with V(2) receptor agonist deficiency.

  9. Toxicological implications of polymorphisms in receptors for xenobiotic chemicals: The case of the aryl hydrocarbon receptor

    International Nuclear Information System (INIS)

    Okey, Allan B.; Franc, Monique A.; Moffat, Ivy D.; Tijet, Nathalie; Boutros, Paul C.; Korkalainen, Merja; Tuomisto, Jouko; Pohjanvirta, Raimo

    2005-01-01

    Mechanistic toxicology has predominantly been focused on adverse effects that are caused by reactive metabolites or by reactive oxygen species. However, many important xenobiotics exert their toxicity, not by generating reactive products, but rather by altering expression of specific genes. In particular, some environmental contaminants target nuclear receptors that function as regulators of transcription. For example, binding of xenobiotic chemicals to steroid receptors is a principle mechanism of endocrine disruption. The aryl hydrocarbon receptor (AHR) mediates toxicity of dioxin-like compounds. In mice, a polymorphism in the AHR ligand-binding domain reduces binding affinity by about 10-fold in the DBA/2 strain compared with the C57BL/6 strain; consequently, dose-response curves for numerous biochemical and toxic effects are shifted about one log to the right in DBA/2 mice. In the Han/Wistar (Kuopio) (H/W) rat strain, a polymorphism causes a deletion of 38 or 43 amino acids from the AHR transactivation domain. This deletion is associated with a greater than 1000-fold resistance to lethality from 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Genes in the conventional AH gene battery (e.g. CYP1A1, CYP1A2, CYP1B1, ALDH3A1, NQO1 and UGT1A1) remain responsive to TCDD in H/W rats despite the large deletion. However, the deletion may selectively alter the receptor's ability to dysregulate specific genes that are key to dioxin toxicity. We are identifying these genes using an expression array approach in dioxin-sensitive vs. dioxin-resistant rat strains and lines. Polymorphisms exist in the human AH receptor, but thus far they have not been shown to have any substantial effect on human responses to AHR-ligands

  10. Anti-schistosomal intervention targets identified by lifecycle transcriptomic analyses.

    Directory of Open Access Journals (Sweden)

    Jennifer M Fitzpatrick

    2009-11-01

    known sequence similarity outside the Platyhelminthes, which were undetectable by the statistical comparisons.Collectively, statistical and network-based exploratory analyses of transcriptomic datasets have led to a thorough characterisation of schistosome development. Information obtained from these experiments highlighted key transcriptional programs associated with lifecycle progression and identified numerous anti-schistosomal candidate molecules including G-protein coupled receptors, tetraspanins, Dyp-type peroxidases, fucosyltransferases, leishmanolysins and the netrin/netrin receptor complex.

  11. CLONING, EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR ALPHA FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    Science.gov (United States)

    In vitro screening assays designed to identify hormone mimics or antagonists, including those recommended for use in the EPA's Tier 1 screening battery, typically use mammalian estrogen (ER) and androgen receptors (AR) such as rat or human. Although we know that the amino acid s...

  12. Founder effect in the Horn of Africa for an insulin receptor mutation that may impair receptor recycling

    DEFF Research Database (Denmark)

    Raffan, E; Soos, M A; Rocha, N

    2011-01-01

    Genetic insulin receptoropathies are a rare cause of severe insulin resistance. We identified the Ile119Met missense mutation in the insulin receptor INSR gene, previously reported in a Yemeni kindred, in four unrelated patients with Somali ancestry. We aimed to investigate a possible genetic...

  13. Identifying Androgen Receptor-Independent Mechanisms of Prostate Cancer Resistance to Second-Generation Antiandrogen Therapy

    Science.gov (United States)

    2016-08-01

    topics in descriptive and inferential statistics including hypothesis testing, regression, and multivariate analysis. I look forward to continuing my...analysis, and CRISPR/Cas9 gene editing. To facilitate my clinical-translational skills, I took part in a statistics seminar course that covered... statistics and data science training with further coursework this year offered at MSKCC and through massive open online courses (MOOCs

  14. THE USE OF POSITRON EMISSION TOMOGRAPHY IN IDENTIFYING AND QUANTIFYING RECEPTORS INVOLVED IN SCHIZOPHRENIA.

    Energy Technology Data Exchange (ETDEWEB)

    VOLKOW,N.D.; WOLF,A.P.

    1991-01-01

    Schizophrenia is a devasting mental disorder that is the focus of a great deal of research. Some symptoms of the disease, such as auditory hallucinations and delusions, can be ameliorated with drug treatment, whereas other symptoms, such as social withdrawal and cognitive decline, remain uncontrolled. It is possible that these latter symptoms that are often termed ''negative symptoms'' are the result of anatomical and neurochemical abnormalities, whereas those symptoms of the disease such as auditory hallucinations that are termed ''positive symptoms'' may be a result of only neurochemical disorders. The drugs used to treat schizophrenia are designated neuroleptics. The term neuroleptic was chosen to emphasize the similarity of pharmacological profiles of drugs with entirely different chemical structures. Especially prominent features of the effects of neuroleptics include the following: a state of affective indifference; a decrease in locomotor activity; a decrease in excitation, agitation, and aggressiveness; and an antipsychotic action in patients with acute as well as chronic psychoses.

  15. Acquired RhD mosaicism identifies fibrotic transformation of thrombopoietin receptor-mutated essential thrombocythemia.

    Science.gov (United States)

    Montemayor-Garcia, Celina; Coward, Rebecca; Albitar, Maher; Udani, Rupa; Jain, Prachi; Koklanaris, Eleftheria; Battiwalla, Minoo; Keel, Siobán; Klein, Harvey G; Barrett, A John; Ito, Sawa

    2017-09-01

    Acquired copy-neutral loss of heterozygosity has been described in myeloid malignant progression with an otherwise normal karyotype. A 65-year-old woman with MPL-mutated essential thrombocythemia and progression to myelofibrosis was noted upon routine pretransplant testing to have mixed field reactivity with anti-D and an historic discrepancy in RhD type. The patient had never received transfusions or transplantation. Gel immunoagglutination revealed group A red blood cells and a mixed-field reaction for the D phenotype, with a predominant D-negative population and a small subset of circulating red blood cells carrying the D antigen. Subsequent genomic microarray single nucleotide polymorphism profiling revealed copy-neutral loss of heterozygosity of chromosome 1 p36.33-p34.2, a known molecular mechanism underlying fibrotic progression of MPL-mutated essential thrombocythemia. The chromosomal region affected by this copy-neutral loss of heterozygosity encompassed the RHD, RHCE, and MPL genes. We propose a model of chronological molecular events that is supported by RHD zygosity assays in peripheral lymphoid and myeloid-derived cells. Copy-neutral loss of heterozygosity events that lead to clonal selection and myeloid malignant progression may also affect the expression of adjacent unrelated genes, including those encoding for blood group antigens. Detection of mixed-field reactions and investigation of discrepant blood typing results are important for proper transfusion support of these patients and can provide useful surrogate markers of myeloproliferative disease progression. © 2017 AABB.

  16. BAF57 Modulation of Androgen Receptor Action and Prostate Cancer Progression

    National Research Council Canada - National Science Library

    Link, Kevin A

    2007-01-01

    Given the requirement of the androgen receptor (AR) activation pathway for prostate cancer growth and progression, it is necessary to identify alternative means of targeting this pathway for the treatment of prostate cancer...

  17. Distinct functional domains contribute to degradation of the low density lipoprotein receptor (LDLR) by the E3 ubiquitin ligase inducible Degrader of the LDLR (IDOL)

    NARCIS (Netherlands)

    Sorrentino, Vincenzo; Scheer, Lilith; Santos, Ana; Reits, Eric; Bleijlevens, Boris; Zelcer, Noam

    2011-01-01

    We recently identified the liver X receptor-regulated E3 ubiquitin ligase inducible degrader of the LDL receptor (IDOL) as a modulator of lipoprotein metabolism. Acting as an E3 ubiquitin ligase, IDOL triggers ubiquitination and subsequent degradation of the low density lipoprotein receptor (LDLR).

  18. P2X receptors in the cardiovascular system and their potential as therapeutic targets in disease.

    Science.gov (United States)

    Ralevic, Vera

    2015-01-01

    This review considers the expression and roles of P2X receptors in the cardiovascular system in health and disease and their potential as therapeutic targets. P2X receptors are ligand gated ion channels which are activated by the endogenous ligand ATP. They are formed from the assembly of three P2X subunit proteins from the complement of seven (P2X1-7), which can associate to form homomeric or heteromeric P2X receptors. The P2X1 receptor is widely expressed in the cardiovascular system, being located in the heart, in the smooth muscle of the majority of blood vessels and in platelets. P2X1 receptors expressed in blood vessels can be activated by ATP coreleased with noradrenaline as a sympathetic neurotransmitter, leading to smooth muscle depolarisation and contraction. There is evidence that the purinergic component of sympathetic neurotransmission is increased in hypertension, identifying P2X1 receptors as a possible therapeutic target in this disorder. P2X3 and P2X2/3 receptors are expressed on cardiac sympathetic neurones and may, through positive feedback of neuronal ATP at this prejunctional site, amplify sympathetic neurotransmission. Activation of P2X receptors expressed in the heart increases cardiac myocyte contractility, and an important role of the P2X4 receptor in this has been identified. Deletion of P2X4 receptors in the heart depresses contractile performance in models of heart failure, while overexpression of P2X4 receptors has been shown to be cardioprotective, thus P2X4 receptors may be therapeutic targets in the treatment of heart disease. P2X receptors have been identified on endothelial cells. Although immunoreactivity for all P2X1-7 receptor proteins has been shown on the endothelium, relatively little is known about their function, with the exception of the endothelial P2X4 receptor, which has been shown to mediate endothelium-dependent vasodilatation to ATP released during shear stress. The potential of P2X receptors as therapeutic targets

  19. In silico comparative genomic analysis of GABAA receptor transcriptional regulation

    Directory of Open Access Journals (Sweden)

    Joyce Christopher J

    2007-06-01

    Full Text Available Abstract Background Subtypes of the GABAA receptor subunit exhibit diverse temporal and spatial expression patterns. In silico comparative analysis was used to predict transcriptional regulatory features in individual mammalian GABAA receptor subunit genes, and to identify potential transcriptional regulatory components involved in the coordinate regulation of the GABAA receptor gene clusters. Results Previously unreported putative promoters were identified for the β2, γ1, γ3, ε, θ and π subunit genes. Putative core elements and proximal transcriptional factors were identified within these predicted promoters, and within the experimentally determined promoters of other subunit genes. Conserved intergenic regions of sequence in the mammalian GABAA receptor gene cluster comprising the α1, β2, γ2 and α6 subunits were identified as potential long range transcriptional regulatory components involved in the coordinate regulation of these genes. A region of predicted DNase I hypersensitive sites within the cluster may contain transcriptional regulatory features coordinating gene expression. A novel model is proposed for the coordinate control of the gene cluster and parallel expression of the α1 and β2 subunits, based upon the selective action of putative Scaffold/Matrix Attachment Regions (S/MARs. Conclusion The putative regulatory features identified by genomic analysis of GABAA receptor genes were substantiated by cross-species comparative analysis and now require experimental verification. The proposed model for the coordinate regulation of genes in the cluster accounts for the head-to-head orientation and parallel expression of the α1 and β2 subunit genes, and for the disruption of transcription caused by insertion of a neomycin gene in the close vicinity of the α6 gene, which is proximal to a putative critical S/MAR.

  20. Modulation of the constitutive activity of the ghrelin receptor by use of pharmacological tools and mutagenesis

    DEFF Research Database (Denmark)

    Mokrosinski, Jacek; Holst, Birgitte

    2010-01-01

    Ghrelin and its receptor are important regulators of metabolic functions, including appetite, energy expenditure, fat accumulation, and growth hormone (GH) secretion. The ghrelin receptor is characterized by an ability to signal even without any ligand present with approximately 50......% of the maximally ghrelin-induced efficacy-a feature that may have important physiological implications. The high basal signaling can be modulated either by administration of specific ligands or by engineering of mutations in the receptor structure. [D-Arg(1), D-Phe(5), D-Trp(7,9), Leu(11)]-substance P...... was the first inverse agonist to be identified for the ghrelin receptor, and this peptide has been used as a starting point for identification of the structural requirements for inverse agonist properties in the ligand. The receptor binding core motif was identified as D-Trp-Phe-D-Trp-Leu-Leu, and elongation...

  1. Morbillivirus receptors and tropism: multiple pathways for infection

    Directory of Open Access Journals (Sweden)

    Hiroki eSato

    2012-03-01

    Full Text Available Morbilliviruses, which include measles virus (MeV, canine distemper virus, and rinderpest virus, are among the most important pathogens in their respective hosts and cause severe syndromes. Morbilliviruses are enveloped viruses with 2 envelope proteins, one of which is hemagglutinin (H protein, which plays a role in binding to cellular receptors. During morbillivirus infection, the virus initially targets lymphoid cells and replicates efficiently in the lymph nodes. The principal cellular receptor for morbillivirus is signaling lymphocyte activation molecule (SLAM, also called CD150, which is exclusively expressed on immune cells. This feature reflects the strong lymphoid cell tropism and viral spread in the infected body. Morbillivirus infection, however, affects various tissues in the body, including the lung, kidney, gastrointestinal tract, vascular endothelium, and brain. Thus, other receptors for morbilliviruses in addition to SLAM might exist. Recently, nectin-4 has been identified as a novel epithelial cell receptor for MeV. The expression of nectin-4 is localized to polarized epithelial cells, and this localization supports the notion of cell tropism since MeV also grows well in the epithelial cells of the respiratory tract. Although 2 major receptors for lymphoid and epithelial cells in natural infection have been identified, morbillivirus can still infect many other types of cells with low infectivity, suggesting the existence of inefficient but ubiquitously expressed receptors. We have identified other molecules that are implicated in morbillivirus infection of SLAM-negative cells by alternative mechanisms. These findings indicate that morbillivirus utilizes multiple pathways for establishment of infection. These studies will advance our understanding of morbillivirus tropism and pathogenesis.

  2. The Evolution of the Scavenger Receptor Cysteine-Rich Domain of the Class A Scavenger Receptors

    Directory of Open Access Journals (Sweden)

    Nicholas eYap

    2015-07-01

    Full Text Available The class A Scavenger Receptor (cA-SR family is a group of five evolutionarily related innate immune receptors. The cA-SRs are known for their promiscuous ligand binding; as they have been shown to bind bacteria such as Streptococcus pneumoniae, and Escherichia coli, as well as different modified forms of low-density lipoprotein. Three of the five family members possess a Scavenger Receptor Cysteine Rich (SRCR domain while the remaining two receptors lack the domain. Previous work has suggested that the Macrophage Associated Receptor with COllagenous structure (MARCO shares a recent common ancestor with the non-SRCR-containing receptors; however the origin of the SRCR domain within the cA-SRs remains unknown. We hypothesize that the SRCR domains of the cA-SRs have a common origin that predates teleost fish. Using the newly available sequence data from sea lamprey and ghost shark genome projects, we have shown that MARCO shares a common ancestor with the SRCR-containing proteins. In addition, we explored the evolutionary relationships within the SRCR domain by reconstructing the ancestral SRCR domains of the cA-SRs. We identified a motif that is highly conserved between the cA-SR SRCR domains and the ancestral SRCR domain that consist of WGTVCDD. We also show that the GRAEVYY motif, a functionally important motif within MARCO, is poorly conserved in the other cA-SRs and in the reconstructed ancestral domain. Further, we identified three sites within MARCO’s SRCR domain which are under positive selection. Two of these sites lie adjacent to the conserved WGTVCDD motif, and may indicate a potential biological function for these sites. Together these findings indicate a common origin of the SRCR domain within the cA-SRs; however different selective pressures between the proteins may have caused MARCOs SRCR domain to evolve to contain different functional motifs when compared to the other SRCR-containing cA-SRs.

  3. Quantitative receptor radioautography in the study of receptor-receptor interactions in the nucleus tractus solitarii

    Directory of Open Access Journals (Sweden)

    Fior-Chadi D.R.

    1998-01-01

    Full Text Available The nucleus tractus solitarii (NTS in the dorsomedial medulla comprises a wide range of neuropeptides and biogenic amines. Several of them are related to mechanisms of central blood pressure control. Angiotensin II (Ang II, neuropeptide Y (NPY and noradrenaline (NA are found in the NTS cells, as well as their receptors. Based on this observation we have evaluated the modulatory effect of these peptide receptors on a2-adrenoceptors in the NTS. Using quantitative receptor radioautography, we observed that NPY and Ang II receptors decreased the affinity of a2-adrenoceptors for their agonists in the NTS of the rat. Cardiovascular experiments agreed with the in vitro data. Coinjection of a threshold dose of Ang II or of the NPY agonists together with an ED50 dose of adrenergic agonists such as NA, adrenaline and clonidine counteracted the depressor effect produced by the a2-agonist in the NTS. The results provide evidence for the existence of an antagonistic interaction between Ang II at1 receptors and NPY receptor subtypes with the a2-adrenoceptors in the NTS. This receptor interaction may reduce the transduction over the a2-adrenoceptors which can be important in central cardiovascular regulation and in the development of hypertension

  4. Olfactory receptors in non-chemosensory tissues

    Directory of Open Access Journals (Sweden)

    NaNa Kang & JaeHyung Koo*

    2012-11-01

    Full Text Available Olfactory receptors (ORs detect volatile chemicals that lead tothe initial perception of smell in the brain. The olfactory receptor(OR is the first protein that recognizes odorants in theolfactory signal pathway and it is present in over 1,000 genesin mice. It is also the largest member of the G protein-coupledreceptors (GPCRs. Most ORs are extensively expressed in thenasal olfactory epithelium where they perform the appropriatephysiological functions that fit their location. However, recentwhole-genome sequencing shows that ORs have been foundoutside of the olfactory system, suggesting that ORs may playan important role in the ectopic expression of non-chemosensorytissues. The ectopic expressions of ORs and their physiologicalfunctions have attracted more attention recently sinceMOR23 and testicular hOR17-4 have been found to be involvedin skeletal muscle development, regeneration, and humansperm chemotaxis, respectively. When identifying additionalexpression profiles and functions of ORs in non-olfactorytissues, there are limitations posed by the small number ofantibodies available for similar OR genes. This review presentsthe results of a research series that identifies ectopic expressionsand functions of ORs in non-chemosensory tissues toprovide insight into future research directions.

  5. The odorant receptor co-receptor from the bed bug, Cimex lectularius L.

    Directory of Open Access Journals (Sweden)

    Immo A Hansen

    Full Text Available Recently, the bed bug, Cimex lectularius L. has re-emerged as a serious and growing problem in many parts of the world. Presence of resistant bed bugs and the difficulty to eliminate them has renewed interest in alternative control tactics. Similar to other haematophagous arthropods, bed bugs rely on their olfactory system to detect semiochemicals in the environment. Previous studies have morphologically characterized olfactory organs of bed bugs' antenna and have physiologically evaluated the responses of olfactory receptor neurons (ORNs to host-derived chemicals. To date, odorant binding proteins (OBPs and odorant receptors (ORs associated with these olfaction processes have not been studied in bed bugs. Chemoreception in insects requires formation of heteromeric complexes of ORs and a universal OR coreceptor (Orco. Orco is the constant chain of every odorant receptor in insects and is critical for insect olfaction but does not directly bind to odorants. Orco agonists and antagonists have been suggested as high-value targets for the development of novel insect repellents. In this study, we have performed RNAseq of bed bug sensory organs and identified several odorant receptors as well as Orco. We characterized Orco expression and investigated the effect of chemicals targeting Orco on bed bug behavior and reproduction. We have identified partial cDNAs of six C. lectularius OBPs and 16 ORs. Full length bed bug Orco was cloned and sequenced. Orco is widely expressed in different parts of the bed bug including OR neurons and spermatozoa. Treatment of bed bugs with the agonist VUAA1 changed bed bug pheromone-induced aggregation behavior and inactivated spermatozoa. We have described and characterized for the first time OBPs, ORs and Orco in bed bugs. Given the importance of these molecules in chemoreception of this insect they are interesting targets for the development of novel insect behavior modifiers.

  6. Sparse Linear Identifiable Multivariate Modeling

    DEFF Research Database (Denmark)

    Henao, Ricardo; Winther, Ole

    2011-01-01

    and bench-marked on artificial and real biological data sets. SLIM is closest in spirit to LiNGAM (Shimizu et al., 2006), but differs substantially in inference, Bayesian network structure learning and model comparison. Experimentally, SLIM performs equally well or better than LiNGAM with comparable......In this paper we consider sparse and identifiable linear latent variable (factor) and linear Bayesian network models for parsimonious analysis of multivariate data. We propose a computationally efficient method for joint parameter and model inference, and model comparison. It consists of a fully...

  7. Identifying flares in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Bykerk, Vivian P; Bingham, Clifton O; Choy, Ernest H

    2016-01-01

    to flare, with escalation planned in 61%. CONCLUSIONS: Flares are common in rheumatoid arthritis (RA) and are often preceded by treatment reductions. Patient/MD/DAS agreement of flare status is highest in patients worsening from R/LDA. OMERACT RA flare questions can discriminate between patients with...... Set. METHODS: Candidate flare questions and legacy measures were administered at consecutive visits to Canadian Early Arthritis Cohort (CATCH) patients between November 2011 and November 2014. The American College of Rheumatology (ACR) core set indicators were recorded. Concordance to identify flares...

  8. Peripheral adrenergic receptors in hypertension

    NARCIS (Netherlands)

    Michel, M. C.; Brodde, O. E.; Insel, P. A.

    1990-01-01

    Increased sympathoadrenal activity appears to play an important role in the development or maintenance of elevated blood pressure in hypertensive patients and various animal models of hypertension. Alterations of adrenergic receptor number or responsiveness might contribute to this increased

  9. Are olfactory receptors really olfactive?

    DEFF Research Database (Denmark)

    Giorgi, Franco; Maggio, Roberto; Bruni, Luis Emilio

    2011-01-01

    environmental conditions. By adopting this standpoint, the functional attribution as olfactory or chemotactic sensors to these receptors should not be seen neither as a cause conditioning receptor gene expression, nor as a final effect resulting from genetically predetermined programs, but as a direct...... and odor-decoding processes. However, this type of explanation does not entirely justify the role olfactory receptors have played during evolution, since they are also expressed ectopically in different organs and/or tissues. Homologous olfactory genes have in fact been found in such diverse cells and....../or organs as spermatozoa, testis and kidney where they are assumed to act as chemotactic sensors or renin modulators. To justify their functional diversity, homologous olfactory receptors are assumed to share the same basic role: that of conferring a self-identity to cells or tissues under varying...

  10. Nuclear Receptor Signaling Atlas (NURSA)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Nuclear Receptor Signaling Atlas (NURSA) is designed to foster the development of a comprehensive understanding of the structure, function, and role in disease...

  11. Discovery of tertiary sulfonamides as potent liver X receptor antagonists.

    Science.gov (United States)

    Zuercher, William J; Buckholz, Richard G; Campobasso, Nino; Collins, Jon L; Galardi, Cristin M; Gampe, Robert T; Hyatt, Stephen M; Merrihew, Susan L; Moore, John T; Oplinger, Jeffrey A; Reid, Paul R; Spearing, Paul K; Stanley, Thomas B; Stewart, Eugene L; Willson, Timothy M

    2010-04-22

    Tertiary sulfonamides were identified in a HTS as dual liver X receptor (LXR, NR1H2, and NR1H3) ligands, and the binding affinity of the series was increased through iterative analogue synthesis. A ligand-bound cocrystal structure was determined which elucidated key interactions for high binding affinity. Further characterization of the tertiary sulfonamide series led to the identification of high affinity LXR antagonists. GSK2033 (17) is the first potent cell-active LXR antagonist described to date. 17 may be a useful chemical probe to explore the cell biology of this orphan nuclear receptor.

  12. L-glutamate Receptor In Paramecium

    Science.gov (United States)

    Bernal-Martínez, Juan; Ortega-Soto, Arturo

    2004-09-01

    Behavioral, electrophysiological and biochemical experiments were performed in order to establish the presence of a glutamate receptor in the ciliate Paramecium. It was found that an AMPA/KA receptor is functionally expressed in Paramecium and that this receptor is immunologically and fillogenetically related to the AMPA/KA receptor present in vertebrates.

  13. Receptor-targeted metalloradiopharmaceuticals. Final technical report

    International Nuclear Information System (INIS)

    Green, Mark A.

    2000-01-01

    Copper (II) and platinum (II) coordination complexes were prepared and characterized. These complexes were designed to afford structural homology with steroidal and non-steroidal estrogens for possible use as receptor-targeted radiopharmaceuticals. While weak affinity for the estrogen receptor was detectable, none would appear to have sufficient receptor-affinity for estrogen-receptor-targeted imaging or therapy

  14. [The receptor theory of atherosclerosis].

    Science.gov (United States)

    Likhoded, V G; Bondarenko, V M; Gintsburg, A L

    2010-01-01

    Lipopolysaccharides of Gram-negative bacteria can interact with Toll-like receptor 4 (TLR4) and induce atheroma formation. The risk of atherosclerosis is decreased in case of TLR4 mutation. Other bacterial ligands and endogenous ligands of TLRs can also be involved in induction of atherogenesis. The general concept of atherosclerosis pathogentsis is presented. According to this concept atherogenesis can be initiated by some reactions resulting from interaction of exogenous and endogenous microbial ligands with Toll-like receptors.

  15. Xenobiotics and the Glucocorticoid Receptor

    International Nuclear Information System (INIS)

    Gulliver, Linda S M

    2017-01-01

    Glucocorticoid Receptor (GR) is present in virtually every human cell type. Representing a nuclear receptor superfamily, GR has several different isoforms essentially acting as ligand-dependent transcription factors, regulating glucocorticoid-responsive gene expression in both a positive and a negative manner. Although the natural ligand of the Glucocorticoid Receptor, glucocorticoids (GC) represent only some of the multiple ligands for GR. Xenobiotics, ubiquitous in the environment, bind to GR and are also capable of activating or repressing GR gene expression, thereby modulating GR cell and tissue-specific downstream effects in a multitude of ways that include responses to inflammatory, allergic, metabolic, neoplastic and autoimmune processes. Many xenobiotics, if inadequately metabolized by xenobiotic metabolizing enzymes and not wholly eliminated, could have deleterious toxic effects with potentially lethal consequences. This review examines GR, the genomic and non-genomic actions of natural and synthetic GC and the body's handling of xenobiotic compounds, before reviewing what is presently known about GR's interactions with many of the more commonly encountered and some of the less well known GR-associated xenobiotics. GR promiscuity and crosstalk with other signaling pathways is discussed, alongside novel roles for GR that include mood disorder and addiction. A knowledge of GR interactions with xenobiotics is increasingly relevant when considering aging populations and the related prevalence of neoplastic disease, together with growing concerns around human exposure to mixtures of chemicals in the environment. Furthermore, escalating rates of obesity, Type 2 diabetes; autoimmune, allergy, addiction and mood disorder-related pathologies, require novel targeted interventions and GR appears a promising pharmacological candidate. - Highlights: • Biological impact of xenobiotics acting through Glucocorticoid Receptor. • Promiscuity of Glucocorticoid

  16. Xenobiotics and the Glucocorticoid Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Gulliver, Linda S M, E-mail: linda.gulliver@otago.ac.nz

    2017-03-15

    Glucocorticoid Receptor (GR) is present in virtually every human cell type. Representing a nuclear receptor superfamily, GR has several different isoforms essentially acting as ligand-dependent transcription factors, regulating glucocorticoid-responsive gene expression in both a positive and a negative manner. Although the natural ligand of the Glucocorticoid Receptor, glucocorticoids (GC) represent only some of the multiple ligands for GR. Xenobiotics, ubiquitous in the environment, bind to GR and are also capable of activating or repressing GR gene expression, thereby modulating GR cell and tissue-specific downstream effects in a multitude of ways that include responses to inflammatory, allergic, metabolic, neoplastic and autoimmune processes. Many xenobiotics, if inadequately metabolized by xenobiotic metabolizing enzymes and not wholly eliminated, could have deleterious toxic effects with potentially lethal consequences. This review examines GR, the genomic and non-genomic actions of natural and synthetic GC and the body's handling of xenobiotic compounds, before reviewing what is presently known about GR's interactions with many of the more commonly encountered and some of the less well known GR-associated xenobiotics. GR promiscuity and crosstalk with other signaling pathways is discussed, alongside novel roles for GR that include mood disorder and addiction. A knowledge of GR interactions with xenobiotics is increasingly relevant when considering aging populations and the related prevalence of neoplastic disease, together with growing concerns around human exposure to mixtures of chemicals in the environment. Furthermore, escalating rates of obesity, Type 2 diabetes; autoimmune, allergy, addiction and mood disorder-related pathologies, require novel targeted interventions and GR appears a promising pharmacological candidate. - Highlights: • Biological impact of xenobiotics acting through Glucocorticoid Receptor. • Promiscuity of Glucocorticoid

  17. Alternative splicing, gene localization, and binding of SH2-B to the insulin receptor kinase domain

    OpenAIRE

    Nelms, Keats; O'Neill, Thomas J.; Li, Shiqing; Hubbard, Stevan R.; Gustafson, Thomas A.; Paul, William E.

    1999-01-01

    . The SH2-B protein is an SH2-domain-containing molecule that interacts with a number of phosphorylated kinase and receptor molecules including the insulin receptor. Two isoforms of the SH2-B have been identified and have been proposed to arise through alternate splicing. Here we have identified a third isoform of the SH2-B protein, SH2-Bγ, that interacts specifically with the insulin receptor. This interaction required phosphorylation of residue Y1146 in the triple tyrosine motif within the ...

  18. Nuclear Receptors, RXR, and the Big Bang.

    Science.gov (United States)

    Evans, Ronald M; Mangelsdorf, David J

    2014-03-27

    Isolation of genes encoding the receptors for steroids, retinoids, vitamin D, and thyroid hormone and their structural and functional analysis revealed an evolutionarily conserved template for nuclear hormone receptors. This discovery sparked identification of numerous genes encoding related proteins, termed orphan receptors. Characterization of these orphan receptors and, in particular, of the retinoid X receptor (RXR) positioned nuclear receptors at the epicenter of the "Big Bang" of molecular endocrinology. This Review provides a personal perspective on nuclear receptors and explores their integrated and coordinated signaling networks that are essential for multicellular life, highlighting the RXR heterodimer and its associated ligands and transcriptional mechanism. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Prognostic Value of Estrogen Receptor alpha and Progesterone Receptor Conversion in Distant Breast Cancer Metastases

    NARCIS (Netherlands)

    Hoefnagel, Laurien D. C.; Moelans, Cathy B.; Meijer, S. L.; van Slooten, Henk-Jan; Wesseling, Pieter; Wesseling, Jelle; Westenend, Pieter J.; Bart, Joost; Seldenrijk, Cornelis A.; Nagtegaal, Iris D.; Oudejans, Joost; van der Valk, Paul; van Gils, Carla H.; van der Wall, Elsken; van Diest, Paul J.

    2012-01-01

    BACKGROUND: Changes in the receptor profile of primary breast cancers to their metastases (receptor conversion) have been described for the estrogen receptor alpha (ER alpha) and progesterone receptor (PR). The purpose of this study was to evaluate the impact of receptor conversion for ER alpha and

  20. The PTK7-Related Transmembrane Proteins Off-track and Off-track 2 Are Co-receptors for Drosophila Wnt2 Required for Male Fertility

    OpenAIRE

    Linnemannstöns, Karen; Ripp, Caroline; Honemann-Capito, Mona; Brechtel-Curth, Katja; Hedderich, Marie; Wodarz, Andreas

    2014-01-01

    Wnt proteins regulate many developmental processes and are required for tissue homeostasis in adult animals. The cellular responses to Wnts are manifold and are determined by the respective Wnt ligand and its specific receptor complex in the plasma membrane. Wnt receptor complexes contain a member of the Frizzled family of serpentine receptors and a co-receptor, which commonly is a single-pass transmembrane protein. Vertebrate protein tyrosine kinase 7 (PTK7) was identified as a Wnt co-recept...

  1. Persistent Identifiers as Boundary Objects

    Science.gov (United States)

    Parsons, M. A.; Fox, P. A.

    2017-12-01

    In 1989, Leigh Star and Jim Griesemer defined the seminal concept of `boundary objects'. These `objects' are what Latour calls `immutable mobiles' that enable communication and collaboration across difference by helping meaning to be understood in different contexts. As Star notes, they are a sort of arrangement that allow different groups to work together without (a priori) consensus. Part of the idea is to recognize and allow for the `interpretive flexibility' that is central to much of the `constructivist' approach in the sociology of science. Persistent Identifiers (PIDs) can clearly act as boundary objects, but people do not usually assume that they enable interpretive flexibility. After all, they are meant to be unambiguous, machine-interpretable identifiers of defined artifacts. In this paper, we argue that PIDs can fill at least two roles: 1) That of the standardized form, where there is strong agreement on what is being represented and how and 2) that of the idealized type, a more conceptual concept that allows many different representations. We further argue that these seemingly abstract conceptions actually help us implement PIDs more effectively to link data, publications, various other artifacts, and especially people. Considering PIDs as boundary objects can help us address issues such as what level of granularity is necessary for PIDs, what metadata should be directly associated with PIDs, and what purpose is the PID serving (reference, provenance, credit, etc.). In short, sociological theory can improve data sharing standards and their implementation in a way that enables broad interdisciplinary data sharing and reuse. We will illustrate this with several specific examples of Earth science data.

  2. Prolactin receptor, growth hormone receptor, and putative somatolactin receptor in Mozambique tilapia: tissue specific expression and differential regulation by salinity and fasting.

    Science.gov (United States)

    Pierce, A L; Fox, B K; Davis, L K; Visitacion, N; Kitahashi, T; Hirano, T; Grau, E G

    2007-01-01

    In fish, pituitary growth hormone family peptide hormones (growth hormone, GH; prolactin, PRL; somatolactin, SL) regulate essential physiological functions including osmoregulation, growth, and metabolism. Teleost GH family hormones have both differential and overlapping effects, which are mediated by plasma membrane receptors. A PRL receptor (PRLR) and two putative GH receptors (GHR1 and GHR2) have been identified in several teleost species. Recent phylogenetic analyses and binding studies suggest that GHR1 is a receptor for SL. However, no studies have compared the tissue distribution and physiological regulation of all three receptors. We sequenced GHR2 from the liver of the Mozambique tilapia (Oreochromis mossambicus), developed quantitative real-time PCR assays for the three receptors, and assessed their tissue distribution and regulation by salinity and fasting. PRLR was highly expressed in the gill, kidney, and intestine, consistent with the osmoregulatory functions of PRL. PRLR expression was very low in the liver. GHR2 was most highly expressed in the muscle, followed by heart, testis, and liver, consistent with this being a GH receptor with functions in growth and metabolism. GHR1 was most highly expressed in fat, liver, and muscle, suggesting a metabolic function. GHR1 expression was also high in skin, consistent with a function of SL in chromatophore regulation. These findings support the hypothesis that GHR1 is a receptor for SL. In a comparison of freshwater (FW)- and seawater (SW)-adapted tilapia, plasma PRL was strongly elevated in FW, whereas plasma GH was slightly elevated in SW. PRLR expression was reduced in the gill in SW, consistent with PRL's function in freshwater adaptation. GHR2 was elevated in the kidney in FW, and correlated negatively with plasma GH, whereas GHR1 was elevated in the gill in SW. Plasma IGF-I, but not GH, was reduced by 4 weeks of fasting. Transcript levels of GHR1 and GHR2 were elevated by fasting in the muscle. However

  3. Toll-like receptors in neonatal sepsis.

    LENUS (Irish Health Repository)

    O'Hare, Fiona M

    2013-06-01

    Toll-like receptors are vital transmembrane receptors that initiate the innate immune response to many micro-organisms. The discovery of these receptors has improved our understanding of host-pathogen interactions, and these receptors play an important role in the pathogenesis of multiple neonatal conditions such as sepsis and brain injury. Toll-like receptors, especially TLRs 2 and 4, are associated with necrotizing enterocolitis, periventricular leukomalacia and sepsis.

  4. Nuclear receptor 4a3 (nr4a3 regulates murine mast cell responses and granule content.

    Directory of Open Access Journals (Sweden)

    Gianni Garcia-Faroldi

    Full Text Available Nuclear receptor 4a3 (Nr4a3 is a transcription factor implicated in various settings such as vascular biology and inflammation. We have recently shown that mast cells dramatically upregulate Nuclear receptor 4a3 upon activation, and here we investigated the functional impact of Nuclear receptor 4a3 on mast cell responses. We show that Nuclear receptor 4a3 is involved in the regulation of cytokine/chemokine secretion in mast cells following activation via the high affinity IgE receptor. Moreover, Nuclear receptor 4a3 negatively affects the transcript and protein levels of mast cell tryptase as well as the mast cell's responsiveness to allergen. Together, these findings identify Nuclear receptor 4a3 as a novel regulator of mast cell function.

  5. Principles of agonist recognition in Cys-loop receptors

    Directory of Open Access Journals (Sweden)

    Timothy eLynagh

    2014-04-01

    Full Text Available Cys-loop receptors are ligand-gated ion channels that are activated by a structurally diverse array of neurotransmitters, including acetylcholine, serotonin, glycine and GABA. After the term chemoreceptor emerged over 100 years ago, there was some wait until affinity labeling, molecular cloning, functional studies and X-ray crystallography experiments identified the extracellular interface of adjacent subunits as the principal site of agonist binding. The question of how subtle differences at and around agonist-binding sites of different Cys-loop receptors can accommodate transmitters as chemically diverse as glycine and serotonin has been subject to intense research over the last three decades. This review outlines the functional diversity and current structural understanding of agonist-binding sites, including those of invertebrate Cys-loop receptors. Together, this provides a framework to understand the atomic determinants involved in how these valuable therapeutic targets recognize and bind their ligands.

  6. Chemokine receptor expression by inflammatory T cells in EAE

    DEFF Research Database (Denmark)

    Mony, Jyothi Thyagabhavan; Khorooshi, Reza; Owens, Trevor

    2014-01-01

    Chemokines direct cellular infiltration to tissues, and their receptors and signaling pathways represent targets for therapy in diseases such as multiple sclerosis (MS). The chemokine CCL20 is expressed in choroid plexus, a site of entry of T cells to the central nervous system (CNS). The CCL20...... receptor CCR6 has been reported to be selectively expressed by CD4(+) T cells that produce the cytokine IL-17 (Th17 cells). Th17 cells and interferon-gamma (IFNγ)-producing Th1 cells are implicated in induction of MS and its animal model experimental autoimmune encephalomyelitis (EAE). We have assessed...... whether CCR6 identifies specific inflammatory T cell subsets in EAE. Our approach was to induce EAE, and then examine chemokine receptor expression by cytokine-producing T cells sorted from CNS at peak disease. About 7% of CNS-infiltrating CD4(+) T cells produced IFNγ in flow cytometric cytokine assays...

  7. CD147 is a signaling receptor for cyclophilin B.

    Science.gov (United States)

    Yurchenko, V; O'Connor, M; Dai, W W; Guo, H; Toole, B; Sherry, B; Bukrinsky, M

    2001-11-09

    Cyclophilins A and B (CyPA and CyPB) are cyclosporin A binding proteins that can be secreted in response to inflammatory stimuli. We recently identified CD147 as a cell-surface receptor for CyPA and demonstrated that CD147 is an essential component in the CyPA-initiated signaling cascade that culminates in ERK activation and chemotaxis. Here we demonstrate that CD147 also serves as a receptor for CyPB. CyPB induced Ca(2+) flux and chemotaxis of CD147-transfected, but not control, CHO cells, and the chemotactic response of primary human neutrophils to CyPB was blocked by antibodies to CD147. These results suggest that CD147 serves as a receptor for extracellular cyclophilins. Copyright 2001 Academic Press.

  8. Scavenger Receptor Structure and Function in Health and Disease

    Directory of Open Access Journals (Sweden)

    Izma Abdul Zani

    2015-05-01

    Full Text Available Scavenger receptors (SRs are a ‘superfamily’ of membrane-bound receptors that were initially thought to bind and internalize modified low-density lipoprotein (LDL, though it is currently known to bind to a variety of ligands including endogenous proteins and pathogens. New family of SRs and their properties have been identified in recent years, and have now been classified into 10 eukaryote families, defined as Classes A-J. These receptors are classified according to their sequences, although in each class they are further classified based in the variations of the sequence. Their ability to bind a range of ligands is reflected on the biological functions such as clearance of modified lipoproteins and pathogens. SR members regulate pathophysiological states including atherosclerosis, pathogen infections, immune surveillance, and cancer. Here, we review our current understanding of SR structure and function implicated in health and disease.

  9. Purinergic Receptors: Key Mediators of HIV-1 infection and inflammation

    Directory of Open Access Journals (Sweden)

    Talia H Swartz

    2015-11-01

    Full Text Available Human immunodeficiency virus (HIV-1 causes a chronic infection that afflicts more than 38 million individuals worldwide. While the infection can be suppressed with potent anti-retroviral therapies, individuals infected with HIV have elevated levels of inflammation as indicated by increased T cell activation, soluble biomarkers, and associated morbidity and mortality. A single mechanism linking HIV pathogenesis to this inflammation has yet to be identified. Purinergic receptors are known to mediate inflammation and have been shown to be required for HIV-1 infection at the level of HIV-1 membrane fusion. Here we review the literature on the role of purinergic receptors in HIV-1 infection and associated inflammation and describe a role for these receptors as potential therapeutic targets.

  10. The Janus face of death receptor signalling during tumour immunoediting.

    Directory of Open Access Journals (Sweden)

    Eimear O' Reilly

    2016-10-01

    Full Text Available Cancer immune-surveillance is essential for the inhibition of carcinogenesis. Malignantly transformed cells can be recognised by both the innate and adaptive immune systems through different mechanisms. Immune effector cells induce extrinsic cell death in the identified tumour cells by expressing death ligand cytokines of the tumour necrosis factor ligand family. However, some tumour cells can escape immune elimination and progress. Acquisition of resistance to the death-ligand induced apoptotic pathway can be obtained through cleavage of effector-cell expressed death-ligands into a poorly active form, mutations or silencing of the death receptors or overexpression of decoy receptors and pro-survival proteins. Although the immune system is highly effective in the elimination of malignantly transformed cells, abnormal/ dysfunctional death-ligand signalling curbs its cytotoxicity. Moreover, death receptors can also transmit pro-survival and pro-migratory signals. Consequently, dysfunctional death receptor-mediated apoptosis/necroptosis signalling does not only give a passive resistance against cell death, but actively drives tumour cell motility, invasion and contributes to consequent metastasis. This dual contribution of the death ligand-death receptor signalling in both the early, elimination phase and then in the late, escape phase of the tumour immunoediting process is discussed in this review. Death receptor agonists still hold potential for cancer therapy since they can execute the tumour-eliminating immune-effector function even in the absence of activation of the immune system against the tumour. The opportunities and challenges of developing death receptor agonists into effective cancer therapeutics are also discussed.

  11. Machine learning approaches to decipher hormone and HER2 receptor status phenotypes in breast cancer.

    Science.gov (United States)

    Adabor, Emmanuel S; Acquaah-Mensah, George K

    2017-10-16

    Breast cancer prognosis and administration of therapies are aided by knowledge of hormonal and HER2 receptor status. Breast cancer lacking estrogen receptors, progesterone receptors and HER2 receptors are difficult to treat. Regarding large data repositories such as The Cancer Genome Atlas, available wet-lab methods for establishing the presence of these receptors do not always conclusively cover all available samples. To this end, we introduce median-supplement methods to identify hormonal and HER2 receptor status phenotypes of breast cancer patients using gene expression profiles. In these approaches, supplementary instances based on median patient gene expression are introduced to balance a training set from which we build simple models to identify the receptor expression status of patients. In addition, for the purpose of benchmarking, we examine major machine learning approaches that are also applicable to the problem of finding receptor status in breast cancer. We show that our methods are robust and have high sensitivity with extremely low false-positive rates compared with the well-established methods. A successful application of these methods will permit the simultaneous study of large collections of samples of breast cancer patients as well as save time and cost while standardizing interpretation of outcomes of such studies. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Studies on insulin receptor, 2

    International Nuclear Information System (INIS)

    Sakai, Yukio

    1979-01-01

    The present study is to investigate an influence of starvation and high fat diet on insulin receptor of the plasma membrane by means of radioreceptor assay using 125 I-labelled insulin. Male guinea pigs of Hartley strain were employed for the starvation study, and 125 I-insulin binding capacity on the plasma membrane of the liver and kidney was determined at 24, 48 and 72 hours of the fast after the last meal. Male rats of Wistar strain were employed for the high fat study where the diet containing 35% of butter was fed ad libitum for 38 or 68 days. The animals were killed at the fast of 12 hours, and 125 I-insulin binding capacity on the plasma membrane of the liver was determined. The results obtained are summarized as follows: 1) An increase in 125 I-insulin binding capacity on the plasma membrane of the liver and kidney was observed by the starvation for 24 to 72 hours. 2) The mechanism of the increase by starvation was considered to be different by the organs; it was due to an increase in number of insulin receptor in the liver, and due to an increase in affinity of insulin receptor in the kidney. 3) In non-obese rats fed with high fat diet, the number of insulin receptor on the liver plasma membrane showed a decrease, and this observation clearly indicated that the decrease in number of the receptor did not depend on the obesity. 4) Obese rats also fed with high fat diet presented a decrease in number of insulin receptor without an elevation of insulin levels in the circulating blood. This indicated that at least in the obese rats fed with high fat diet, the decrease in number of the receptor was not due to hyperinsulinemia. (author)

  13. RECOVIR Software for Identifying Viruses

    Science.gov (United States)

    Chakravarty, Sugoto; Fox, George E.; Zhu, Dianhui

    2013-01-01

    Most single-stranded RNA (ssRNA) viruses mutate rapidly to generate a large number of strains with highly divergent capsid sequences. Determining the capsid residues or nucleotides that uniquely characterize these strains is critical in understanding the strain diversity of these viruses. RECOVIR (an acronym for "recognize viruses") software predicts the strains of some ssRNA viruses from their limited sequence data. Novel phylogenetic-tree-based databases of protein or nucleic acid residues that uniquely characterize these virus strains are created. Strains of input virus sequences (partial or complete) are predicted through residue-wise comparisons with the databases. RECOVIR uses unique characterizing residues to identify automatically strains of partial or complete capsid sequences of picorna and caliciviruses, two of the most highly diverse ssRNA virus families. Partition-wise comparisons of the database residues with the corresponding residues of more than 300 complete and partial sequences of these viruses resulted in correct strain identification for all of these sequences. This study shows the feasibility of creating databases of hitherto unknown residues uniquely characterizing the capsid sequences of two of the most highly divergent ssRNA virus families. These databases enable automated strain identification from partial or complete capsid sequences of these human and animal pathogens.

  14. Key Questions for Translation of FFA Receptors: From Pharmacology to Medicines.

    Science.gov (United States)

    Suckow, Arthur T; Briscoe, Celia P

    2017-01-01

    The identification of fatty acids as ligands for the G-protein coupled free fatty acid (FFA) receptor family over 10 years ago led to intensive chemistry efforts to find small-molecule ligands for this class of receptors. Identification of potent, selective modulators of the FFA receptors and their utility in medicine has proven challenging, in part due to their complex pharmacology. Nevertheless, ligands have been identified that are sufficient for exploring the therapeutic potential of this class of receptors in rodents and, in the case of FFA1, FFA2, FFA4, and GPR84, also in humans. Expression profiling, the phenotyping of FFA receptor knockout mice, and the results of studies exploring the effects of these ligands in rodents have uncovered a number of indications where engagement of one or a combination of FFA receptors might provide some clinical benefit in areas including diabetes, inflammatory bowel syndrome, Alzheimer's, pain, and cancer. In this chapter, we will review the clinical potential of modulating FFA receptors based on preclinical and in some cases clinical studies with synthetic ligands. In particular, key aspects and challenges associated with small-molecule ligand identification and FFA receptor pharmacology will be addressed with a view of the hurdles that need to be overcome to fully understand the potential of the receptors as therapeutic targets.

  15. Arctigenin induced gallbladder cancer senescence through modulating epidermal growth factor receptor pathway.

    Science.gov (United States)

    Zhang, Mingdi; Cai, Shizhong; Zuo, Bin; Gong, Wei; Tang, Zhaohui; Zhou, Di; Weng, Mingzhe; Qin, Yiyu; Wang, Shouhua; Liu, Jun; Ma, Fei; Quan, Zhiwei

    2017-05-01

    Gallbladder cancer has poor prognosis and limited therapeutic options. Arctigenin, a representative dibenzylbutyrolactone lignan, occurs in a variety of plants. However, the molecular mechanisms involved in the antitumor effect of arctigenin on gallbladder cancer have not been fully elucidated. The expression levels of epidermal growth factor receptor were examined in 100 matched pairs of gallbladder cancer tissues. A positive correlation between high epidermal growth factor receptor expression levels and poor prognosis was observed in gallbladder cancer tissues. Pharmacological inhibition or inhibition via RNA interference of epidermal growth factor receptor induced cellular senescence in gallbladder cancer cells. The antitumor effect of arctigenin on gallbladder cancer cells was primarily achieved by inducing cellular senescence. In gallbladder cancer cells treated with arctigenin, the expression level of epidermal growth factor receptor significantly decreased. The analysis of the activity of the kinases downstream of epidermal growth factor receptor revealed that the RAF-MEK-ERK signaling pathway was significantly inhibited. Furthermore, the cellular senescence induced by arctigenin could be reverted by pcDNA-epidermal growth factor receptor. Arctigenin also potently inhibited the growth of tumor xenografts, which was accompanied by the downregulation of epidermal growth factor receptor and induction of senescence. This study demonstrates arctigenin could induce cellular senescence in gallbladder cancer through the modulation of epidermal growth factor receptor pathway. These data identify epidermal growth factor receptor as a key regulator in arctigenin-induced gallbladder cancer senescence.

  16. Modulation of receptors and adenylate cyclase activity during sucrose feeding, food deprivation, and cold exposure

    International Nuclear Information System (INIS)

    Scarpace, P.J.; Baresi, L.A.; Morley, J.E.

    1987-01-01

    Thermogenesis in brown adipose tissue (BAT) serves as a regulator of body temperature and weight maintenance. Thermogenesis can be stimulated by catecholamine activation of adenylate cyclase through the β-adrenergic receptor. To investigate the effects of sucrose feeding, food deprivation, and cold exposure on the β-adrenergic pathway, adenylate cyclase activity and β-adrenergic receptors were assessed in rat BAT after 2 wk of sucrose feeding, 2 days of food deprivation, or 2 days of cold exposure. β-Adrenergic receptors were identified in BAT using [ 125 I]iodocyanopindolol. Binding sites had the characteristics of mixed β 1 - and β 2 -type adrenergic receptors at a ratio of 60/40. After sucrose feeding or cold exposure, there was the expected increase in BAT mitochondrial mass as measured by total cytochrome-c oxidase activity but a decrease in β-adrenergic receptor density due to a loss of the β 1 -adrenergic subtype. This BAT β-adrenergic receptor downregulation was tissue specific, since myocardial β-adrenergic receptors were unchanged with either sucrose feeding or cold exposure. Forskolin-stimulated adenylate cyclase activity increased in BAT after sucrose feeding or cold exposure but not after food deprivation. These data suggest that in BAT, sucrose feeding or cold exposure result in downregulation of β-adrenergic receptors and that isoproterenol-stimulated adenylate cyclase activity was limited by receptor availability

  17. Adenosine A2B and A3 receptor location at the mouse neuromuscular junction.

    Science.gov (United States)

    Garcia, Neus; Priego, Mercedes; Hurtado, Erica; Obis, Teresa; Santafe, Manel M; Tomàs, Marta; Lanuza, Maria Angel; Tomàs, Josep

    2014-07-01

    To date, four subtypes of adenosine receptors have been cloned (A(1)R, A(2A)R, A(2B)R, and A(3)R). In a previous study we used confocal immunocytochemistry to identify A(1)R and A(2A)R receptors at mouse neuromuscular junctions (NMJs). The data shows that these receptors are localized differently in the three cells (muscle, nerve and glia) that configure the NMJs. A(1)R localizes in the terminal teloglial Schwann cell and nerve terminal, whereas A(2A)R localizes in the postsynaptic muscle and in the axon and nerve terminal. Here, we use Western blotting to investigate the presence of A(2B)R and A(3)R receptors in striated muscle and immunohistochemistry to localize them in the three cells of the adult neuromuscular synapse. The data show that A(2B)R and A(3)R receptors are present in the nerve terminal and muscle cells at the NMJs. Neither A(2B)R nor A(3)R receptors are localized in the Schwann cells. Thus, the four subtypes of adenosine receptors are present in the motor endings. The presence of these receptors in the neuromuscular synapse allows the receptors to be involved in the modulation of transmitter release. © 2014 Anatomical Society.

  18. Physiology and Emerging Biochemistry of the Glucagon-Like Peptide-1 Receptor

    Directory of Open Access Journals (Sweden)

    Francis S. Willard

    2012-01-01

    Full Text Available The glucagon-like peptide-1 (GLP-1 receptor is one of the best validated therapeutic targets for the treatment of type 2 diabetes mellitus (T2DM. Over several years, the accumulation of basic, translational, and clinical research helped define the physiologic roles of GLP-1 and its receptor in regulating glucose homeostasis and energy metabolism. These efforts provided much of the foundation for pharmaceutical development of the GLP-1 receptor peptide agonists, exenatide and liraglutide, as novel medicines for patients suffering from T2DM. Now, much attention is focused on better understanding the molecular mechanisms involved in ligand induced signaling of the GLP-1 receptor. For example, advancements in biophysical and structural biology techniques are being applied in attempts to more precisely determine ligand binding and receptor occupancy characteristics at the atomic level. These efforts should better inform three-dimensional modeling of the GLP-1 receptor that will help inspire more rational approaches to identify and optimize small molecule agonists or allosteric modulators targeting the GLP-1 receptor. This article reviews GLP-1 receptor physiology with an emphasis on GLP-1 induced signaling mechanisms in order to highlight new molecular strategies that help determine desired pharmacologic characteristics for guiding development of future nonpeptide GLP-1 receptor activators.

  19. Mechanoreceptor afferent activity compared with receptor field dimensions and pressure changes in feline urinary bladder.

    Science.gov (United States)

    Downie, J W; Armour, J A

    1992-11-01

    The relationship between vesical mechanoreceptor field dimensions and afferent nerve activity recorded in pelvic plexus nerve filaments was examined in chloralose-anesthetized cats. Orthogonal receptor field dimensions were monitored with piezoelectric ultrasonic crystals. Reflexly generated bladder contractile activity made measurements difficult, therefore data were collected from cats subjected to actual sacral rhizotomy. Afferent activity was episodic and was initiated at different pressure and receptor field dimension thresholds. Maximum afferent activity did not correlate with maximum volume or pressure. Furthermore, activity was not linearly related to intravesical pressure, receptor field dimensions, or calculated wall tension. Pressure-length hysteresis of the receptor fields occurred. The responses of identified afferent units and their associated receptor field dimensions to brief contractions elicited by the ganglion stimulant 1,1-dimethyl-4-phenylpiperazinium iodide (2.5-20 micrograms i.a.), studied under constant volume or constant pressure conditions, are compatible with bladder mechanoreceptors behaving as tension receptors. Because activity generated by bladder mechanoreceptors did not correlate in a simple fashion with intravesical pressure or receptor field dimensions, it is concluded that such receptors are influenced by the viscoelastic properties of the bladder wall. Furthermore, as a result of the heterogeneity of the bladder wall, receptor field tension appears to offer a more precise relationship with the activity of bladder wall mechanoreceptors than does intravesical pressure.

  20. Herpes simplex virus infection is sensed by both Toll-like receptors and retinoic acid-inducible gene- like receptors, which synergize to induce type I interferon production

    DEFF Research Database (Denmark)

    Rasmussen, Simon B; Jensen, Søren B; Nielsen, Christoffer

    2009-01-01

    The innate antiviral response is initiated by pattern recognition receptors, which recognize viral pathogen-associated molecular patterns. Here we show that retinoic acid-inducible gene (RIG)-I-like receptors (RLRs) in cooperation with Toll-like receptor (TLR) 9 is required for expression of type I...... interferons (IFNs) after infection with herpes simplex virus (HSV). Our work also identified RNase L as a critical component in IFN induction. Moreover, we found that TLR9 and RLRs activate distinct, as well as overlapping, intracellular signalling pathways. Thus, RLRs are important for recognition of HSV...

  1. Identification of an estrogenic hormone receptor in Caenorhabditis elegans

    International Nuclear Information System (INIS)

    Mimoto, Ai; Fujii, Madoka; Usami, Makoto; Shimamura, Maki; Hirabayashi, Naoko; Kaneko, Takako; Sasagawa, Noboru; Ishiura, Shoichi

    2007-01-01

    Changes in both behavior and gene expression occur in Caenorhabditis elegans following exposure to sex hormones such as estrogen and progesterone, and to bisphenol A (BPA), an estrogenic endocrine-disrupting compound. However, only one steroid hormone receptor has been identified. Of the 284 known nuclear hormone receptors (NHRs) in C. elegans, we selected nhr-14, nhr-69, and nhr-121 for analysis as potential estrogenic hormone receptors, because they share sequence similarity with the human estrogen receptor. First, the genes were cloned and expressed in Escherichia coli, and then the affinity of each protein for estrogen was determined using a surface plasmon resonance (SPR) biosensor. All three NHRs bound estrogen in a dose-dependent fashion. To evaluate the specificity of the binding, we performed a solution competition assay using an SPR biosensor. According to our results, only NHR-14 was able to interact with estrogen. Therefore, we next examined whether nhr-14 regulates estrogen signaling in vivo. To investigate whether these interactions actually control the response of C. elegans to hormones, we investigated the expression of vitellogenin, an estrogen responsive gene, in an nhr-14 mutant. Semi-quantitative RT-PCR showed that vitellogenin expression was significantly reduced in the mutant. This suggests that NHR-14 is a C. elegans estrogenic hormone receptor and that it controls gene expression in response to estrogen

  2. Evolution of ligand specificity in vertebrate corticosteroid receptors

    Directory of Open Access Journals (Sweden)

    Deitcher David L

    2011-01-01

    Full Text Available Abstract Background Corticosteroid receptors include mineralocorticoid (MR and glucocorticoid (GR receptors. Teleost fishes have a single MR and duplicate GRs that show variable sensitivities to mineralocorticoids and glucocorticoids. How these receptors compare functionally to tetrapod MR and GR, and the evolutionary significance of maintaining two GRs, remains unclear. Results We used up to seven steroids (including aldosterone, cortisol and 11-deoxycorticosterone [DOC] to compare the ligand specificity of the ligand binding domains of corticosteroid receptors between a mammal (Mus musculus and the midshipman fish (Porichthys notatus, a teleost model for steroid regulation of neural and behavioral plasticity. Variation in mineralocorticoid sensitivity was considered in a broader phylogenetic context by examining the aldosterone sensitivity of MR and GRs from the distantly related daffodil cichlid (Neolamprologus pulcher, another teleost model for neurobehavioral plasticity. Both teleost species had a single MR and duplicate GRs. All MRs were sensitive to DOC, consistent with the hypothesis that DOC was the initial ligand of the ancestral MR. Variation in GR steroid-specificity corresponds to nine identified amino acid residue substitutions rather than phylogenetic relationships based on receptor sequences. Conclusion The mineralocorticoid sensitivity of duplicate GRs in teleosts is highly labile in the context of their evolutionary phylogeny, a property that likely led to neo-functionalization and maintenance of two GRs.

  3. Revisiting available knowledge on teleostean thyroid hormone receptors.

    Science.gov (United States)

    Lazcano, Iván; Orozco, Aurea

    2018-03-21

    Teleosts are the most numerous class of living vertebrates. They exhibit great diversity in terms of morphology, developmental strategies, ecology and adaptation. In spite of this diversity, teleosts conserve similarities at molecular, cellular and endocrine levels. In the context of thyroidal systems, and as in the rest of vertebrates, thyroid hormones in fish regulate development, growth and metabolism by actively entering the nucleus and interacting with thyroid hormone receptors, the final sensors of this endocrine signal, to regulate gene expression. In general terms, vertebrates express the functional thyroid hormone receptors alpha and beta, encoded by two distinct genes (thra and thrb, respectively). However, different species of teleosts express thyroid hormone receptor isoforms with particular structural characteristics that confer singular functional traits to these receptors. For example, teleosts contain two thra genes and in some species also two thrb; some of the expressed isoforms can bind alternative ligands. Also, some identified isoforms contain deletions or large insertions that have not been described in other vertebrates and that have not yet been functionally characterized. As in amphibians, the regulation of some of these teleost isoforms coincides with the climax of metamorphosis and/or life transitions during development and growth. In this review, we aimed to gain further insights into thyroid signaling from a comparative perspective by proposing a systematic nomenclature for teleost thyroid hormone receptor isoforms and summarize their particular functional features when the information was available. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Medium-chain fatty acid-sensing receptor, GPR84, is a proinflammatory receptor.

    Science.gov (United States)

    Suzuki, Masakatsu; Takaishi, Sachiko; Nagasaki, Miyuki; Onozawa, Yoshiko; Iino, Ikue; Maeda, Hiroaki; Komai, Tomoaki; Oda, Tomiichiro

    2013-04-12

    G protein-coupled receptor 84 (GPR84) is a putative receptor for medium-chain fatty acids (MCFAs), whose pathophysiological roles have not yet been clarified. Here, we show that GPR84 was activated by MCFAs with the hydroxyl group at the 2- or 3-position more effectively than nonhydroxylated MCFAs. We also identified a surrogate agonist, 6-n-octylaminouracil (6-OAU), for GPR84. These potential ligands and the surrogate agonist, 6-OAU, stimulated [(35)S]GTP binding and accumulated phosphoinositides in a GPR84-dependent manner. The surrogate agonist, 6-OAU, internalized GPR84-EGFP from the cell surface. Both the potential ligands and 6-OAU elicited chemotaxis of human polymorphonuclear leukocytes (PMNs) and macrophages and amplified LPS-stimulated production of the proinflammatory cytokine IL-8 from PMNs and TNFα from macrophages. Furthermore, the intravenous injection of 6-OAU raised the blood CXCL1 level in rats, and the inoculation of 6-OAU into the rat air pouch accumulated PMNs and macrophages in the site. Our results indicate a proinflammatory role of GPR84, suggesting that the receptor may be a novel target to treat chronic low grade inflammation associated-disease.

  5. Tyrosine 769 of the keratinocyte growth factor receptor is required for receptor signaling but not endocytosis

    International Nuclear Information System (INIS)

    Ceridono, Mara; Belleudi, Francesca; Ceccarelli, Simona; Torrisi, Maria Rosaria

    2005-01-01

    Keratinocyte growth factor receptor (KGFR) is a receptor tyrosine kinase expressed on epithelial cells which belongs to the family of fibroblast growth factor receptors (FGFRs). Following ligand binding, KGFR is rapidly autophosphorylated on specific tyrosine residues in the intracellular domain, recruits substrate proteins, and is rapidly internalized by clathrin-mediated endocytosis. The role of different autophosphorylation sites in FGFRs, and in particular the role of the tyrosine 766 in FGFR1, first identified as PLCγ binding site, has been extensively studied. We analyzed here the possible role of the tyrosine 769 in KGFR, corresponding to tyrosine 766 in FGFR1, in the regulation of KGFR signal transduction and MAPK activation as well as in the control of the endocytic process of KGFR. A mutant KGFR in which tyrosine 769 was substituted by phenylalanine was generated and transfected in NIH3T3 and HeLa cells. Our results indicate that tyrosine 769 is required for the binding to KGFR and tyrosine phosphorylation of PLCγ as well as for the full activation of MAPKs and for cell proliferation through the regulation of FRS2 tyrosine phosphorylation, suggesting that this residue represents a key regulator of KGFR signal transduction. Our data also show that tyrosine 769 is not involved in the regulation of the endocytic process of KGFR

  6. Reading the viral signature by Toll-like receptors and other pattern recognition receptors.

    Science.gov (United States)

    Mogensen, Trine H; Paludan, Søren R

    2005-03-01

    Successful host defense against viral infections relies on early production of type I interferon (IFN) and subsequent activation of a cellular cytotoxic response. The acute IFN and inflammatory response against virus infections is mediated by cellular pattern-recognition receptors (PRRs) that recognize specific molecular structures on viral particles or products of viral replication. Toll-like receptors (TLRs) constitute a class of membrane-bound PRRs capable of detecting microbial infections. While TLR2 and TLR4, which were first identified to recognize Gram-positive and Gram-negative bacteria, respectively, sense specific viral proteins on the cell surface, TLRs 3, 7, 8, and 9 serve as receptors for viral nucleic acids in endosomic compartments. In addition to TLRs, cells express cytoplasmic PRRs such as the RNA helicase retinoic acid inducible gene I and the kinase double-stranded RNA-activated protein kinase R, both of which sense dsRNA, a characteristic signature of viral replication, and initiate a protective cellular response. Here we review the recent progress in our understanding of PRRs and viral infections and discuss the molecular and cellular responses evoked by virus-activated PRRs. Finally, we look into what is currently known about the role of PRRs in viral infections in vivo.

  7. Testin, a novel binding partner of the calcium-sensing receptor, enhances receptor-mediated Rho-kinase signalling

    International Nuclear Information System (INIS)

    Magno, Aaron L.; Ingley, Evan; Brown, Suzanne J.; Conigrave, Arthur D.; Ratajczak, Thomas; Ward, Bryan K.

    2011-01-01

    Highlights: → A yeast two-hybrid screen revealed testin bound to the calcium-sensing receptor. → The second zinc finger of LIM domain 1 of testin is critical for interaction. → Testin bound to a region of the receptor tail important for cell signalling. → Testin and receptor interaction was confirmed in mammalian (HEK293) cells. → Overexpression of testin enhanced receptor-mediated Rho signalling in HEK293 cells. -- Abstract: The calcium-sensing receptor (CaR) plays an integral role in calcium homeostasis and the regulation of other cellular functions including cell proliferation and cytoskeletal organisation. The multifunctional nature of the CaR is manifested through ligand-dependent stimulation of different signalling pathways that are also regulated by partner binding proteins. Following a yeast two-hybrid library screen using the intracellular tail of the CaR as bait, we identified several novel binding partners including the focal adhesion protein, testin. Testin has not previously been shown to interact with cell surface receptors. The sites of interaction between the CaR and testin were mapped to the membrane proximal region of the receptor tail and the second zinc-finger of LIM domain 1 of testin, the integrity of which was found to be critical for the CaR-testin interaction. The CaR-testin association was confirmed in HEK293 cells by coimmunoprecipitation and confocal microscopy studies. Ectopic expression of testin in HEK293 cells stably expressing the CaR enhanced CaR-stimulated Rho activity but had no effect on CaR-stimulated ERK signalling. These results suggest an interplay between the CaR and testin in the regulation of CaR-mediated Rho signalling with possible effects on the cytoskeleton.

  8. α1b-Adrenergic Receptor Localization and Relationship to the D1-Dopamine Receptor in the Rat Nucleus Accumbens.

    Science.gov (United States)

    Mitrano, Darlene A; Jackson, Kelsey; Finley, Samantha; Seeley, Allison

    2018-02-10

    The α1-adrenergic receptors (α1ARs) have been implicated in numerous actions of the brain, including attention and wakefulness. Additionally, they have been identified as contributing to disorders of the brain, such as drug addiction, and recent work has shown a role of these receptors in relapse to psychostimulants. While some functionality is known, the actual subcellular localization of the subtypes of the α1ARs remains to be elucidated. Further, their anatomical relationship to receptors for other neurotransmitters, such as dopamine (DA), remains unclear. Therefore, using immunohistochemistry and electron microscopy techniques, this study describes the subcellular localization of the α1b-adrenergic receptor (α1bAR), the subtype most tied to relapse behaviors, as well as its relationship to the D1-dopamine receptor (D1R) in both the shell and core of the rat nucleus accumbens (NAc). Overall, α1bARs were found in unmyelinated axons and axon terminals with some labeling in dendrites. In accordance with other studies of the striatum, the D1R was found mainly in dendrites and spines; therefore, colocalization of the D1R with the α1bAR was rare postsynaptically. However, in the NAc shell, when the receptors were co-expressed in the same neuronal elements there was a trend for both receptors to be found on the plasma membrane, as opposed to the intracellular compartment. This study provides valuable anatomical information about the α1bAR and its relationship to the D1R and the regulation of DA and norepinephrine (NE) neurotransmission in the brain which have been examined previously. Published by Elsevier Ltd.

  9. Regulated internalization of NMDA receptors drives PKD1-mediated suppression of the activity of residual cell-surface NMDA receptors.

    Science.gov (United States)

    Fang, Xiao-Qian; Qiao, Haifa; Groveman, Bradley R; Feng, Shuang; Pflueger, Melissa; Xin, Wen-Kuan; Ali, Mohammad K; Lin, Shuang-Xiu; Xu, Jindong; Duclot, Florian; Kabbaj, Mohamed; Wang, Wei; Ding, Xin-Sheng; Santiago-Sim, Teresa; Jiang, Xing-Hong; Salter, Michael W; Yu, Xian-Min

    2015-11-19

    Constitutive and regulated internalization of cell surface proteins has been extensively investigated. The regulated internalization has been characterized as a principal mechanism for removing cell-surface receptors from the plasma membrane, and signaling to downstream targets of receptors. However, so far it is still not known whether the functional properties of remaining (non-internalized) receptor/channels may be regulated by internalization of the same class of receptor/channels. The N-methyl-D-aspartate receptor (NMDAR) is a principal subtype of glutamate-gated ion channel and plays key roles in neuronal plasticity and memory functions. NMDARs are well-known to undergo two types of regulated internalization - homologous and heterologous, which can be induced by high NMDA/glycine and DHPG, respectively. In the present work, we investigated effects of regulated NMDAR internalization on the activity of residual cell-surface NMDARs and neuronal functions. In electrophysiological experiments we discovered that the regulated internalization of NMDARs not only reduced the number of cell surface NMDARs but also caused an inhibition of the activity of remaining (non-internalized) surface NMDARs. In biochemical experiments we identified that this functional inhibition of remaining surface NMDARs was mediated by increased serine phosphorylation of surface NMDARs, resulting from the activation of protein kinase D1 (PKD1). Knockdown of PKD1 did not affect NMDAR internalization but prevented the phosphorylation and inhibition of remaining surface NMDARs and NMDAR-mediated synaptic functions. These data demonstrate a novel concept that regulated internalization of cell surface NMDARs not only reduces the number of NMDARs on the cell surface but also causes an inhibition of the activity of remaining surface NMDARs through intracellular signaling pathway(s). Furthermore, modulating the activity of remaining surface receptors may be an effective approach for treating receptor

  10. Large-scale production and study of a synthetic G protein-coupled receptor: Human olfactory receptor 17-4

    Science.gov (United States)

    Cook, Brian L.; Steuerwald, Dirk; Kaiser, Liselotte; Graveland-Bikker, Johanna; Vanberghem, Melanie; Berke, Allison P.; Herlihy, Kara; Pick, Horst; Vogel, Horst; Zhang, Shuguang

    2009-01-01

    Although understanding of the olfactory system has progressed at the level of downstream receptor signaling and the wiring of olfactory neurons, the system remains poorly understood at the molecular level of the receptors and their interaction with and recognition of odorant ligands. The structure and functional mechanisms of these receptors still remain a tantalizing enigma, because numerous previous attempts at the large-scale production of functional olfactory receptors (ORs) have not been successful to date. To investigate the elusive biochemistry and molecular mechanisms of olfaction, we have developed a mammalian expression system for the large-scale production and purification of a functional OR protein in milligram quantities. Here, we report the study of human OR17-4 (hOR17-4) purified from a HEK293S tetracycline-inducible system. Scale-up of production yield was achieved through suspension culture in a bioreactor, which enabled the preparation of >10 mg of monomeric hOR17-4 receptor after immunoaffinity and size exclusion chromatography, with expression yields reaching 3 mg/L of culture medium. Several key post-translational modifications were identified using MS, and CD spectroscopy showed the receptor to be ≈50% α-helix, similar to other recently determined G protein-coupled receptor structures. Detergent-solubilized hOR17-4 specifically bound its known activating odorants lilial and floralozone in vitro, as measured by surface plasmon resonance. The hOR17-4 also recognized specific odorants in heterologous cells as determined by calcium ion mobilization. Our system is feasible for the production of large quantities of OR necessary for structural and functional analyses and research into OR biosensor devices. PMID:19581598

  11. Photoaffinity labeling of the follitropin receptor

    International Nuclear Information System (INIS)

    Shin, J.; Ji, T.H.

    1985-01-01

    A photoactivatable derivative of human follitropin was used to identify the follitropin receptor on porcine granulosa cells. The hormone was condensed with a heterobifunctional reagent, the N-hydroxysuccinimide ester of 4-azidobenzoylglycine, and radioiodinated. The 125 I-labeled hormone derivative associated with the same number of receptors as 125 I-hormone itself, but with a slightly lower Ka, 1.12 X 10(10) M-1 compared with 1.4 X 10(10) M-1 for the 125 I-hormone. The binding could be blocked with untreated hormone. Its alpha and beta subunits could be cross-linked to produce alpha beta dimer by photolysis. When the 125 I-hormone derivative bound to the cells was photolyzed for crosslinking and the products resolved by electrophoresis on sodium dodecyl sulfate-polyacrylamide gels under reducing conditions, two new bands (106 and 61 kDa) of lower electrophoretic mobility appeared in addition to the alpha, beta, and alpha beta bands. Formation of these crosslinked complexes required photolysis, and the 125 I-hormone derivative specifically bound to cells bearing the receptor. Binding could be blocked by excess untreated follitropin but not with human choriogonadotropin and thyrotropin. Under nonreducing conditions, one major band (104 kDa) of cross-linked complexes appeared. Upon reduction with dithiothreitol and second-dimensional electrophoresis, the 104-kDa band produced two smaller complexes of 75 and 61 kDa, indicating the loss of two components and the existence of intercomponent disulfides. Successful production of the 104-kDa complex requires blocking of free sulfhydryl groups with N-ethylmaleimide. It is, however, independent of various protease inhibitors or the temperature and the time period of hormone incubation with cells or the plasma membrane fraction. The mass estimates and the interaction with the hormone of the photoaffinity-labeled components are discussed

  12. Photoaffinity labeling of the follitropin receptor

    Energy Technology Data Exchange (ETDEWEB)

    Shin, J.; Ji, T.H.

    1985-11-15

    A photoactivatable derivative of human follitropin was used to identify the follitropin receptor on porcine granulosa cells. The hormone was condensed with a heterobifunctional reagent, the N-hydroxysuccinimide ester of 4-azidobenzoylglycine, and radioiodinated. The SVI-labeled hormone derivative associated with the same number of receptors as SVI-hormone itself, but with a slightly lower Ka, 1.12 X 10(10) M-1 compared with 1.4 X 10(10) M-1 for the SVI-hormone. The binding could be blocked with untreated hormone. Its alpha and beta subunits could be cross-linked to produce alpha beta dimer by photolysis. When the SVI-hormone derivative bound to the cells was photolyzed for crosslinking and the products resolved by electrophoresis on sodium dodecyl sulfate-polyacrylamide gels under reducing conditions, two new bands (106 and 61 kDa) of lower electrophoretic mobility appeared in addition to the alpha, beta, and alpha beta bands. Formation of these crosslinked complexes required photolysis, and the SVI-hormone derivative specifically bound to cells bearing the receptor. Binding could be blocked by excess untreated follitropin but not with human choriogonadotropin and thyrotropin. Under nonreducing conditions, one major band (104 kDa) of cross-linked complexes appeared. Upon reduction with dithiothreitol and second-dimensional electrophoresis, the 104-kDa band produced two smaller complexes of 75 and 61 kDa, indicating the loss of two components and the existence of intercomponent disulfides. Successful production of the 104-kDa complex requires blocking of free sulfhydryl groups with N-ethylmaleimide. It is, however, independent of various protease inhibitors or the temperature and the time period of hormone incubation with cells or the plasma membrane fraction. The mass estimates and the interaction with the hormone of the photoaffinity-labeled components are discussed.

  13. Taking two to tango: a role for ghrelin receptor heterodimerization in stress and reward.

    Science.gov (United States)

    Schellekens, Harriët; Dinan, Timothy G; Cryan, John F

    2013-08-30

    The gut hormone, ghrelin, is the only known peripherally derived orexigenic signal. It activates its centrally expressed receptor, the growth hormone secretagogue receptor (GHS-R1a), to stimulate food intake. The ghrelin signaling system has recently been suggested to play a key role at the interface of homeostatic control of appetite and the hedonic aspects of food intake, as a critical role for ghrelin in dopaminergic mesolimbic circuits involved in reward signaling has emerged. Moreover, enhanced plasma ghrelin levels are associated with conditions of physiological stress, which may underline the drive to eat calorie-dense "comfort-foods" and signifies a role for ghrelin in stress-induced food reward behaviors. These complex and diverse functionalities of the ghrelinergic system are not yet fully elucidated and likely involve crosstalk with additional signaling systems. Interestingly, accumulating data over the last few years has shown the GHS-R1a receptor to dimerize with several additional G-protein coupled receptors (GPCRs) involved in appetite signaling and reward, including the GHS-R1b receptor, the melanocortin 3 receptor (MC3), dopamine receptors (D1 and D2), and more recently, the serotonin 2C receptor (5-HT2C). GHS-R1a dimerization was shown to affect downstream signaling and receptor trafficking suggesting a potential novel mechanism for fine-tuning GHS-R1a receptor mediated activity. This review summarizes ghrelin's role in food reward and stress and outlines the GHS-R1a dimer pairs identified to date. In addition, the downstream signaling and potential functional consequences of dimerization of the GHS-R1a receptor in appetite and stress-induced food reward behavior are discussed. The existence of multiple GHS-R1a heterodimers has important consequences for future pharmacotherapies as it significantly increases the pharmacological diversity of the GHS-R1a receptor and has the potential to enhance specificity of novel ghrelin-targeted drugs.

  14. β1-adrenergic receptors activate two distinct signaling pathways in striatal neurons

    Science.gov (United States)

    Meitzen, John; Luoma, Jessie I.; Stern, Christopher M.; Mermelstein, Paul G.

    2010-01-01

    Monoamine action in the dorsal striatum and nucleus accumbens plays essential roles in striatal physiology. Although research often focuses on dopamine and its receptors, norepinephrine and adrenergic receptors are also crucial in regulating striatal function. While noradrenergic neurotransmission has been identified in the striatum, little is known regarding the signaling pathways activated by β-adrenergic receptors in this brain region. Using cultured striatal neurons, we characterized a novel signaling pathway by which activation of β1-adrenergic receptors leads to the rapid phosphorylation of cAMP Response Element Binding Protein (CREB), a transcription-factor implicated as a molecular switch underlying long-term changes in brain function. Norepinephrine-mediated CREB phosphorylation requires β1-adrenergic receptor stimulation of a receptor tyrosine kinase, ultimately leading to the activation of a Ras/Raf/MEK/MAPK/MSK signaling pathway. Activation of β1-adrenergic receptors also induces CRE-dependent transcription and increased c-fos expression. In addition, stimulation of β1-adrenergic receptors produces cAMP production, but surprisingly, β1-adrenergic receptor activation of adenylyl cyclase was not functionally linked to rapid CREB phosphorylation. These findings demonstrate that activation of β1-adrenergic receptors on striatal neurons can stimulate two distinct signaling pathways. These adrenergic actions can produce long-term changes in gene expression, as well as rapidly modulate cellular physiology. By elucidating the mechanisms by which norepinephrine and β1-adrenergic receptor activation affects striatal physiology, we provide the means to more fully understand the role of monoamines in modulating striatal function, specifically how norepinephrine and β1-adrenergic receptors may affect striatal physiology. PMID:21143600

  15. The nuclear receptor gene family in the Pacific oyster, Crassostrea gigas, contains a novel subfamily group.

    Science.gov (United States)

    Vogeler, Susanne; Galloway, Tamara S; Lyons, Brett P; Bean, Tim P

    2014-05-15

    Nuclear receptors are a superfamily of transcription factors important in key biological, developmental and reproductive processes. Several of these receptors are ligand- activated and through their ability to bind endogenous and exogenous ligands, are potentially vulnerable to xenobiotics. Molluscs are key ecological species in defining aquatic and terrestrial habitats and are sensitive to xenobiotic compounds in the environment. However, the understanding of nuclear receptor presence, function and xenobiotic disruption in the phylum Mollusca is limited. Here, forty-three nuclear receptor sequences were mined from the genome of the Pacific oyster, Crassostrea gigas. They include members of NR0-NR5 subfamilies, notably lacking any NR6 members. Phylogenetic analyses of the oyster nuclear receptors have been conducted showing the presence of a large novel subfamily group not previously reported, which is named NR1P. Homologues to all previous identified nuclear receptors in other mollusc species have also been determined including the putative heterodimer partner retinoid X receptor, estrogen receptor and estrogen related receptor. C. gigas contains a highly diverse set of nuclear receptors including a novel NR1 group, which provides important information on presence and evolution of this transcription factor superfamily in invertebrates. The Pacific oyster possesses two members of NR3, the sex steroid hormone receptor analogues, of which there are 9 in humans. This provides increasing evidence that steroid ligand specific expansion of this family is deuterostome specific. This new knowledge on divergence and emergence of nuclear receptors in C. gigas provides essential information for studying regulation of molluscan gene expression and the potential effects of xenobiotics.

  16. Identifying ELIXIR Core Data Resources.

    Science.gov (United States)

    Durinx, Christine; McEntyre, Jo; Appel, Ron; Apweiler, Rolf; Barlow, Mary; Blomberg, Niklas; Cook, Chuck; Gasteiger, Elisabeth; Kim, Jee-Hyub; Lopez, Rodrigo; Redaschi, Nicole; Stockinger, Heinz; Teixeira, Daniel; Valencia, Alfonso

    2016-01-01

    The core mission of ELIXIR is to build a stable and sustainable infrastructure for biological information across Europe. At the heart of this are the data resources, tools and services that ELIXIR offers to the life-sciences community, providing stable and sustainable access to biological data. ELIXIR aims to ensure that these resources are available long-term and that the life-cycles of these resources are managed such that they support the scientific needs of the life-sciences, including biological research. ELIXIR Core Data Resources are defined as a set of European data resources that are of fundamental importance to the wider life-science community and the long-term preservation of biological data. They are complete collections of generic value to life-science, are considered an authority in their field with respect to one or more characteristics, and show high levels of scientific quality and service. Thus, ELIXIR Core Data Resources are of wide applicability and usage. This paper describes the structures, governance and processes that support the identification and evaluation of ELIXIR Core Data Resources. It identifies key indicators which reflect the essence of the definition of an ELIXIR Core Data Resource and support the promotion of excellence in resource development and operation. It describes the specific indicators in more detail and explains their application within ELIXIR's sustainability strategy and science policy actions, and in capacity building, life-cycle management and technical actions. The identification process is currently being implemented and tested for the first time. The findings and outcome will be evaluated by the ELIXIR Scientific Advisory Board in March 2017. Establishing the portfolio of ELIXIR Core Data Resources and ELIXIR Services is a key priority for ELIXIR and publicly marks the transition towards a cohesive infrastructure.

  17. DIA-datasnooping and identifiability

    Science.gov (United States)

    Zaminpardaz, S.; Teunissen, P. J. G.

    2018-04-01

    In this contribution, we present and analyze datasnooping in the context of the DIA method. As the DIA method for the detection, identification and adaptation of mismodelling errors is concerned with estimation and testing, it is the combination of both that needs to be considered. This combination is rigorously captured by the DIA estimator. We discuss and analyze the DIA-datasnooping decision probabilities and the construction of the corresponding partitioning of misclosure space. We also investigate the circumstances under which two or more hypotheses are nonseparable in the identification step. By means of a theorem on the equivalence between the nonseparability of hypotheses and the inestimability of parameters, we demonstrate that one can forget about adapting the parameter vector for hypotheses that are nonseparable. However, as this concerns the complete vector and not necessarily functions of it, we also show that parameter functions may exist for which adaptation is still possible. It is shown how this adaptation looks like and how it changes the structure of the DIA estimator. To demonstrate the performance of the various elements of DIA-datasnooping, we apply the theory to some selected examples. We analyze how geometry changes in the measurement setup affect the testing procedure, by studying their partitioning of misclosure space, the decision probabilities and the minimal detectable and identifiable biases. The difference between these two minimal biases is highlighted by showing the difference between their corresponding contributing factors. We also show that if two alternative hypotheses, say Hi and Hj , are nonseparable, the testing procedure may have different levels of sensitivity to Hi -biases compared to the same Hj -biases.

  18. Purinergic Receptors in Ocular Inflammation

    Directory of Open Access Journals (Sweden)

    Ana Guzman-Aranguez

    2014-01-01

    Full Text Available Inflammation is a complex process that implies the interaction between cells and molecular mediators, which, when not properly “tuned,” can lead to disease. When inflammation affects the eye, it can produce severe disorders affecting the superficial and internal parts of the visual organ. The nucleoside adenosine and nucleotides including adenine mononucleotides like ADP and ATP and dinucleotides such as P1,P4-diadenosine tetraphosphate (Ap4A, and P1,P5-diadenosine pentaphosphate (Ap5A are present in different ocular locations and therefore they may contribute/modulate inflammatory processes. Adenosine receptors, in particular A2A adenosine receptors, present anti-inflammatory action in acute and chronic retinal inflammation. Regarding the A3 receptor, selective agonists like N6-(3-iodobenzyl-5′-N-methylcarboxamidoadenosine (CF101 have been used for the treatment of inflammatory ophthalmic diseases such as dry eye and uveoretinitis. Sideways, diverse stimuli (sensory stimulation, large intraocular pressure increases can produce a release of ATP from ocular sensory innervation or after injury to ocular tissues. Then, ATP will activate purinergic P2 receptors present in sensory nerve endings, the iris, the ciliary body, or other tissues surrounding the anterior chamber of the eye to produce uveitis/endophthalmitis. In summary, adenosine and nucleotides can activate receptors in ocular structures susceptible to suffer from inflammatory processes. This involvement suggests the possible use of purinergic agonists and antagonists as therapeutic targets for ocular inflammation.

  19. Fine-mapping identifies two additional breast cancer susceptibility loci at 9q31.2

    DEFF Research Database (Denmark)

    Orr, Nick; Dudbridge, Frank; Dryden, Nicola

    2015-01-01

    We recently identified a novel susceptibility variant, rs865686, for estrogen-receptor positive breast cancer at 9q31.2. Here, we report a fine-mapping analysis of the 9q31.2 susceptibility locus using 43 160 cases and 42 600 controls of European ancestry ascertained from 52 studies and a further...

  20. Fine-mapping identifies two additional breast cancer susceptibility loci at 9q31.2

    NARCIS (Netherlands)

    N. Orr (Nick); F. Dudbridge (Frank); N. Dryden (Nicola); S. Maguire (Sarah); D. Novo (Daniela); E. Perrakis (Eleni); N. Johnson (Nichola); M. Ghoussaini (Maya); J. Hopper (John); M.C. Southey (Melissa); C. Apicella (Carmel); J. Stone (Jennifer); M.K. Schmidt (Marjanka); A. Broeks (Annegien); L.J. van 't Veer (Laura); F.B.L. Hogervorst (Frans); P.A. Fasching (Peter); L. Haeberle (Lothar); A.B. Ekici (Arif); M.W. Beckmann (Matthias); L.J. Gibson (Lorna); A. Aitken; H. Warren (Helen); E.J. Sawyer (Elinor); I.P. Tomlinson (Ian); M. Kerin (Michael); N. Miller (Nicola); B. Burwinkel (Barbara); F. Marme (Federick); A. Schneeweiss (Andreas); C. Sohn (Chistof); P. Guénel (Pascal); T. Truong (Thérèse); E. Cordina-Duverger (Emilie); M. Sanchez (Marie); S.E. Bojesen (Stig); B.G. Nordestgaard (Børge); S.F. Nielsen (Sune); H. Flyger (Henrik); J. Benítez (Javier); M.P. Zamora (Pilar); J.I.A. Perez (Jose Ignacio Arias); P. Menéndez (Primitiva); H. Anton-Culver (Hoda); S.L. Neuhausen (Susan); H. Brenner (Hermann); A.K. Dieffenbach (Aida Karina); V. Arndt (Volker); C. Stegmaier (Christa); U. Hamann (Ute); H. Brauch (Hiltrud); C. Justenhoven (Christina); T. Brüning (Thomas); Y.-D. Ko (Yon-Dschun); H. Nevanlinna (Heli); K. Aittomäki (Kristiina); C. Blomqvist (Carl); S. Khan (Sofia); N.V. Bogdanova (Natalia); T. Dörk (Thilo); A. Lindblom (Annika); S. Margolin (Sara); A. Mannermaa (Arto); V. Kataja (Vesa); V-M. Kosma (Veli-Matti); J.M. Hartikainen (J.); G. Chenevix-Trench (Georgia); J. Beesley (Jonathan); D. Lambrechts (Diether); M. Moisse (Matthieu); O.A.M. Floris; B. Beuselinck (B.); J. Chang-Claude (Jenny); A. Rudolph (Anja); P. Seibold (Petra); D. Flesch-Janys (Dieter); P. Radice (Paolo); P. Peterlongo (Paolo); B. Peissel (Bernard); V. Pensotti (Valeria); F.J. Couch (Fergus); J.E. Olson (Janet); S. Slettedahl (Seth); C. Vachon (Celine); G.G. Giles (Graham G.); R.L. Milne (Roger L.); C.A. McLean (Catriona Ann); C.A. Haiman (Christopher); B.E. Henderson (Brian); F.R. Schumacher (Fredrick); L. Le Marchand (Loic); J. Simard (Jacques); M.S. Goldberg (Mark); F. Labrèche (France); M. Dumont (Martine); V. Kristensen (Vessela); G.G. Alnæs (Grethe); S. Nord (Silje); A.-L. Borresen-Dale (Anne-Lise); W. Zheng (Wei); S.L. Deming-Halverson (Sandra); M. Shrubsole (Martha); J. Long (Jirong); R. Winqvist (Robert); K. Pykäs (Katri); A. Jukkola-Vuorinen (Arja); M. Grip (Mervi); I.L. Andrulis (Irene); J.A. Knight (Julia); G. Glendon (Gord); S. Tchatchou (Sandrine); P. Devilee (Peter); R.A.E.M. Tollenaar (Robertus A. E. M.); C.M. Seynaeve (Caroline); C.J. van Asperen (Christi); M. García-Closas (Montserrat); J.D. Figueroa (Jonine); S.J. Chanock (Stephen); J. Lissowska (Jolanta); K. Czene (Kamila); H. Darabi (Hatef); M. Eriksson (Mikael); D. Klevebring (Daniel); M.J. Hooning (Maartje); A. Hollestelle (Antoinette); C.H.M. van Deurzen (Carolien); M. Kriege (Mieke); P. Hall (Per); J. Li (Jingmei); J. Liu (Jianjun); M.K. Humphreys (Manjeet); A. Cox (Angela); S.S. Cross (Simon); M.W.R. Reed (Malcolm); P.D.P. Pharoah (Paul); A.M. Dunning (Alison); M. Shah (Mitul); B. Perkins (Barbara); A. Jakubowska (Anna); J. Lubinski (Jan); K. Jaworska-Bieniek (Katarzyna); K. Durda (Katarzyna); A. Ashworth (Alan); A.J. Swerdlow (Anthony ); M. Jones (Michael); M. Schoemaker (Minouk); A. Meindl (Alfons); R.K. Schmutzler (Rita); C. Olswold (Curtis); S. Slager (Susan); A.E. Toland (Amanda); D. Yannoukakos (Drakoulis); K.R. Muir (K.); A. Lophatananon (Artitaya); S. Stewart-Brown (Sarah); P. Siriwanarangsan (Pornthep); K. Matsuo (Keitaro); H. Ito (Hidema); H. Iwata (Hisato); J. Ishiguro (Junko); A.H. Wu (Anna H.); C.-C. Tseng (Chiu-chen); D. Van Den Berg (David); D.O. Stram (Daniel O.); S.-H. Teo (Soo-Hwang); C.H. Yip (Cheng Har); P. Kang (Peter); M.K. Ikram (Kamran); X.-O. Shu (Xiao-Ou); W. Lu (Wei); Y. Gao; H. Cai (Hui); D. Kang (Daehee); J.-Y. Choi (J.); S.K. Park (Sue); D-Y. Noh (Dong-Young); J.M. Hartman (Joost); X. Miao; W.-Y. Lim (Wei-Yen); S.C. Lee (Soo Chin); S. Sangrajrang (Suleeporn); V. Gaborieau (Valerie); P. Brennan (Paul); J.D. McKay (James); P.-E. Wu (Pei-Ei); M.-F. Hou (Ming-Feng); J-C. Yu (Jyh-Cherng); C-Y. Shen (Chen-Yang); W.J. Blot (William); Q. Cai (Qiuyin); L.B. Signorello (Lisa B.); C. Luccarini (Craig); C. Bayes (Caroline); S. Ahmed (Shahana); M. Maranian (Melanie); S. Healey (Sue); A. González-Neira (Anna); G. Pita (Guillermo); M. Rosario Alonso; N. Álvarez (Nuria); D. Herrero (Daniel); D.C. Tessier (Daniel C.); D. Vincent (Daniel); F. Bacot (Francois); D. Hunter (David); S. Lindstrom (Stephen); J. Dennis (Joe); K. Michailidou (Kyriaki); M.K. Bolla (Manjeet); D.F. Easton (Douglas); I. dos Santos Silva (Isabel); O. Fletcher (Olivia); J. Peto (Julian)

    2015-01-01

    textabstractWe recently identified a novel susceptibility variant, rs865686, for estrogen-receptor positive breast cancer at 9q31.2. Here, we report a fine-mapping analysis of the 9q31.2 susceptibility locus using 43 160 cases and 42 600 controls of European ancestry ascertained from 52 studies and

  1. Photo-antagonism of the GABAA receptor.

    Science.gov (United States)

    Mortensen, Martin; Iqbal, Favaad; Pandurangan, Arun P; Hannan, Saad; Huckvale, Rosemary; Topf, Maya; Baker, James R; Smart, Trevor G

    2014-07-29

    Neurotransmitter receptor trafficking is fundamentally important for synaptic transmission and neural network activity. GABAA receptors and inhibitory synapses are vital components of brain function, yet much of our knowledge regarding receptor mobility and function at inhibitory synapses is derived indirectly from using recombinant receptors, antibody-tagged native receptors and pharmacological treatments. Here we describe the use of a set of research tools that can irreversibly bind to and affect the function of recombinant and neuronal GABAA receptors following ultraviolet photoactivation. These compounds are based on the competitive antagonist gabazine and incorporate a variety of photoactive groups. By using site-directed mutagenesis and ligand-docking studies, they reveal new areas of the GABA binding site at the interface between receptor β and α subunits. These compounds enable the selected inactivation of native GABAA receptor populations providing new insight into the function of inhibitory synapses and extrasynaptic receptors in controlling neuronal excitation.

  2. Localization of the fourth membrane spanning domain as a ligand binding site in the human platelet α2-adrenergic receptor

    International Nuclear Information System (INIS)

    Matsui, Hiroaki; Lefkowitz, R.J.; Caron, M.G.; Regan, J.W.

    1989-01-01

    The human platelet α 2 -adrenergic receptor is an integral membrane protein which binds epinephrine. The gene for this receptor has been cloned, and the primary structure is thus known. A model of its secondary structure predicts that the receptor has seven transmembrane spanning domains. By covalent labeling and peptide mapping, the authors have identified a region of the receptor that is directly involved with ligand binding. Partially purified preparations of the receptor were covalently radiolabeled with either of two specific photoaffinity ligands: [ 3 H]SKF 102229 (an antagonist) or p-azido[ 3 H]clonidine (an agonist). The radiolabeled receptors were then digested with specific endopeptidases, and peptides containing the covalently bound radioligands were identified. Lysylendopeptidase treatment of [ 3 H]SKF 102229 labeled receptor yielded one peptide of M r 2400 as the product of a complete digest. Endopeptidase Arg-C gave a labeled peptide of M r 4000, which was further digested to the M r 2400 peptide by additional treatment with lysylendopeptidase. Using p-azido[ 3 H]clonidine-labeled receptor, a similar M r 2400 peptide was obtained by lysylendopeptidase cleavage. This M r 2400 peptide corresponds to the fourth transmembrane spanning domain of the receptor. These data suggest that this region forms part of the ligand binding domain of the human platelet α 2 -adrenergic receptor

  3. Ric-8A, a Gα protein guanine nucleotide exchange factor potentiates taste receptor signaling

    Directory of Open Access Journals (Sweden)

    Claire J Fenech

    2009-10-01

    Full Text Available Taste receptors for sweet, bitter and umami tastants are G-protein coupled receptors (GPCRs. While much effort has been devoted to understanding G-protein-receptor interactions and identifying the components of the signalling cascade downstream of these receptors, at the level of the G-protein the modulation of receptor signal transduction remains relatively unexplored. In this regard a taste-specific regulator of G-protein signaling (RGS, RGS21, has recently been identified. To study whether guanine nucleotide exchange factors (GEFs are involved in the transduction of the signal downstream of the taste GPCRs we investigated the expression of Ric-8A and Ric-8B in mouse taste cells and their interaction with G-protein subunits found in taste buds. Mammalian Ric-8 proteins were initially identified as potent GEFs for a range of Gα subunits and Ric-8B has recently been shown to amplify olfactory signal transduction. We find that both Ric-8A and Ric-8B are expressed in a large portion of taste bud cells and that most of these cells contain IP3R-3 a marker for sweet, umami and bitter taste receptor cells. Ric-8A interacts with Gα-gustducin and Gαi2 through which it amplifies the signal transduction of hTas2R16, a receptor for bitter compounds. Overall, these findings are consistent with a role for Ric-8 in mammalian taste signal transduction.

  4. Naturally occurring glucagon-like peptide-2 (GLP-2) receptors in human intestinal cell lines.

    Science.gov (United States)

    Sams, Anette; Hastrup, Sven; Andersen, Marie; Thim, Lars

    2006-02-17

    Although clinical trials with GLP-2 receptor agonists are currently ongoing, the mechanisms behind GLP-2-induced intestinal epithelial growth remain to be understood. To approach the GLP-2 mechanism of action this study aimed to identify intestinal cell lines endogenously expressing the GLP-2 receptor. Here we report the first identification of a cell line endogenously expressing functional GLP-2 receptors. The human intestinal epithelial cell line, FHC, expressed GLP-2 receptor encoding mRNA (RT-PCR) and GLP-2 receptor protein (Western blot). In cultured FHC cells, GLP-2 induced concentration dependent cAMP accumulation (pEC(50)=9.7+/-0.04 (mean+/-S.E.M., n=4)). In addition, a naturally occurring human intestinal fibroblast cell line, 18Co, endogenously expressing GLP-2 receptor encoding mRNA (RT-PCR) and protein (Western blot) was identified. No receptor functionality (binding or G-protein signalling) could be demonstrated in 18Co cells. The identified gut-relevant cell lines provide tools for future clarification of the mechanisms underlying GLP-2-induced epithelial growth.

  5. Functional characterization of bursicon receptor and genome-wide analysis for identification of genes affected by bursicon receptor RNAi

    Science.gov (United States)

    Bai, Hua; Palli, Subba R.

    2010-01-01

    Bursicon is an insect neuropeptide hormone that is secreted from the central nervous system into the hemolymph and initiates cuticle tanning. The receptor for bursicon is encoded by the rickets (rk) gene and belongs to the G protein-coupled receptor (GPCR) superfamily. The bursicon and its receptor regulate cuticle tanning as well as wing expansion after adult eclosion. However, the molecular action of bursicon signaling remains unclear. We utilized RNA interference (RNAi) and microarray to study the function of the bursicon receptor (Tcrk) in the model insect, Tribolium castaneum. The data included here showed that in addition to cuticle tanning and wing expansion reported previously, Tcrk is also required for development and expansion of integumentary structures and adult eclosion. Using custom microarrays, we identified 24 genes that are differentially expressed between Tcrk RNAi and control insects. Knockdown in the expression of one of these genes, TC004091, resulted in the arrest of adult eclosion. Identification of genes that are involved in bursicon receptor mediated biological processes will provide tools for future studies on mechanisms of bursicon action. PMID:20457145

  6. Purification of the active C5a receptor from human polymorphonuclear leukocytes as a receptor - G sub i complex

    Energy Technology Data Exchange (ETDEWEB)

    Rollins, T.E.; Siciliano, S.; Kobayashi, S.; Cianciarulo, D.N.; Bonilla-Argudo, V.; Collier, K.; Springer, M.S. (Merck Sharp and Dohme Research Lab., Rahway, NJ (United States))

    1991-02-01

    The authors have isolated, in an active state, the C5a receptor from human polymorphonuclear leukocytes. The purification was achieved in a single step using a C5a affinity column in which the C5a molecule was coupled to the resin through its N terminus. The purified receptor, like the crude solubilized molecule, exhibited a single class of high-affinity binding sites with a K{sub d} of 30 pM. Further, the binding of C5a retained its sensitivity to guanine nucleotides, implying that the purified receptor contained a guanine nucleotide-binding protein (G protein). SDS/PAGE revealed the presence of three polypeptides with molecular masses of 42, 40, and 36 kDa, which were determined to be the C5a-binding subunit and the {alpha} and {beta} subunits of G{sub i}, respectively. The 36- and 40-kDa polypeptides were identified by immunoblotting and by the ability of pertussis toxin to ADP-ribosylate the 40-kDa molecule. These results confirm their earlier hypothesis that the receptor exists as a complex with a G protein in the presence or absence of C5a. The tight coupling between the receptor and G protein should make possible the identification of the G protein(s) involved in the transduction pathways used by C5a to produce its many biological effects.

  7. Purification of the active C5a receptor from human polymorphonuclear leukocytes as a receptor - Gi complex

    International Nuclear Information System (INIS)

    Rollins, T.E.; Siciliano, S.; Kobayashi, S.; Cianciarulo, D.N.; Bonilla-Argudo, V.; Collier, K.; Springer, M.S.

    1991-01-01

    The authors have isolated, in an active state, the C5a receptor from human polymorphonuclear leukocytes. The purification was achieved in a single step using a C5a affinity column in which the C5a molecule was coupled to the resin through its N terminus. The purified receptor, like the crude solubilized molecule, exhibited a single class of high-affinity binding sites with a K d of 30 pM. Further, the binding of C5a retained its sensitivity to guanine nucleotides, implying that the purified receptor contained a guanine nucleotide-binding protein (G protein). SDS/PAGE revealed the presence of three polypeptides with molecular masses of 42, 40, and 36 kDa, which were determined to be the C5a-binding subunit and the α and β subunits of G i , respectively. The 36- and 40-kDa polypeptides were identified by immunoblotting and by the ability of pertussis toxin to ADP-ribosylate the 40-kDa molecule. These results confirm their earlier hypothesis that the receptor exists as a complex with a G protein in the presence or absence of C5a. The tight coupling between the receptor and G protein should make possible the identification of the G protein(s) involved in the transduction pathways used by C5a to produce its many biological effects

  8. Functional labeling of insulin receptor subunits in live cells. Alpha 2 beta 2 species is the major autophosphorylated form

    International Nuclear Information System (INIS)

    Le Marchand-Brustel, Y.; Ballotti, R.; Gremeaux, T.; Tanti, J.F.; Brandenburg, D.; Van Obberghen, E.

    1989-01-01

    Both receptor subunits were functionally labeled in order to provide methods allowing, in live cells and in broken cell systems, concomitant evaluation of the insulin receptor dual function, hormone binding, and kinase activity. In cell-free systems, insulin receptors were labeled on their alpha-subunit with 125I-photoreactive insulin, and on their beta-subunit by autophosphorylation. Thereafter, phosphorylated receptors were separated from the complete set of receptors by means of anti-phosphotyrosine antibodies. Using this approach, a subpopulation of receptors was found which had bound insulin, but which were not phosphorylated. Under nonreducing conditions, receptors appeared in three oligomeric species identified as alpha 2 beta 2, alpha 2 beta, and alpha 2. Mainly the alpha 2 beta 2 receptor species was found to be phosphorylated while insulin was bound to alpha 2 beta 2, alpha 2 beta, and alpha 2 forms. In live cells, biosynthetic labeling of insulin receptors was used. Receptors were first labeled with [35S]methionine. Subsequently, the addition of insulin led to receptor autophosphorylation by virtue of the endogenous ATP pool. The total amount of [35S]methionine-labeled receptors was precipitated with antireceptor antibodies, whereas with anti-phosphotyrosine antibodies, only the phosphorylated receptors were isolated. Using this approach we made the two following key findings: (1) Both receptor species, alpha 2 beta 2 and alpha 2 beta, are present in live cells and in comparable amounts. This indicates that the alpha 2 beta form is not a degradation product of the alpha 2 beta 2 form artificially generated during receptor preparation. (2) The alpha 2 beta 2 species is the prevalently autophosphorylated form

  9. Human pregnane X receptor is activated by dibenzazepine carbamate-based inhibitors of constitutive androstane receptor.

    Science.gov (United States)

    Jeske, Judith; Windshügel, Björn; Thasler, Wolfgang E; Schwab, Matthias; Burk, Oliver

    2017-06-01

    Unintentional activation of xenosensing nuclear receptors pregnane X receptor (PXR) and/or constitutive androstane receptor (CAR) by clinical drug use is known to produce severe side effects in patients, which may be overcome by co-administering antagonists. However, especially antagonizing CAR is hampered by the lack of specific inhibitors, which do not activate PXR. Recently, compounds based on a dibenzazepine carbamate scaffold were identified as potent CAR inhibitors. However, their potential to activate PXR was not thoroughly investigated, even if the lead compound was named "CAR inhibitor not PXR activator 1" (CINPA1). Thus, we performed a comprehensive analysis of the interaction of CINPA1 and four analogs with PXR. Cellular assays were used to investigate intra- and intermolecular interactions and transactivation activity of PXR as a function of the compounds. Modulation of PXR target gene expression was analyzed in primary human hepatocytes. Ligand binding to PXR was investigated by molecular docking and limited proteolytic digestion. We show here that CINPA1 induced the assembly of the PXR ligand-binding domain, released co-repressors from and recruited co-activators to the receptor. CINPA1 and its analogs induced the PXR-dependent activation of a CYP3A4 reporter gene and CINPA1 induced the expression of endogenous cytochrome P450 genes in primary hepatocytes, while not consistently inhibiting CAR-mediated induction. Molecular docking revealed favorable binding of CINPA1 and analogs to the PXR ligand-binding pocket, which was confirmed in vitro. Altogether, our data provide consistent evidence that compounds with a dibenzazepine carbamate scaffold, such as CINPA1 and its four analogs, bind to and activate PXR.

  10. CINPA1 Is an Inhibitor of Constitutive Androstane Receptor That Does Not Activate Pregnane X Receptor

    Science.gov (United States)

    Cherian, Milu T; Lin, Wenwei; Wu, Jing

    2015-01-01

    Constitutive androstane receptor (CAR) and pregnane X receptor (PXR) are xenobiotic sensors that enhance the detoxification and elimination of xenobiotics and endobiotics by modulating the expression of genes encoding drug-metabolizing enzymes and transporters. Elevated levels of drug-metabolizing enzymes and efflux transporters, resulting from CAR activation in various cancers, promote the elimination of chemotherapeutic agents, leading to reduced therapeutic effectiveness and acquired drug resistance. CAR inhibitors, in combination with existing chemotherapeutics, could therefore be used to attenuate multidrug resistance in cancers. Interestingly, all previously reported CAR inverse-agonists are also activators of PXR, rendering them mechanistically counterproductive in tissues where both these xenobiotic receptors are present and active. We used a directed high-throughput screening approach, followed by subsequent mechanistic studies, to identify novel, potent, and specific small-molecule CAR inhibitors that do not activate PXR. We describe here one such inhibitor, CINPA1 (CAR inhibitor not PXR activator 1), capable of reducing CAR-mediated transcription with an IC50 of ∼70 nM. CINPA1 1) is a specific xenobiotic receptor inhibitor and has no cytotoxic effects up to 30 µM; 2) inhibits CAR-mediated gene expression in primary human hepatocytes, where CAR is endogenously expressed; 3) does not alter the protein levels or subcellular localization of CAR; 4) increases corepressor and reduces coactivator interaction with the CAR ligand-binding domain in mammalian two-hybrid assays; and 5) disrupts CAR binding to the promoter regions of target genes in chromatin immunoprecipitation assays. CINPA1 could be used as a novel molecular tool for understanding CAR function. PMID:25762023

  11. CINPA1 is an inhibitor of constitutive androstane receptor that does not activate pregnane X receptor.

    Science.gov (United States)

    Cherian, Milu T; Lin, Wenwei; Wu, Jing; Chen, Taosheng

    2015-05-01

    Constitutive androstane receptor (CAR) and pregnane X receptor (PXR) are xenobiotic sensors that enhance the detoxification and elimination of xenobiotics and endobiotics by modulating the expression of genes encoding drug-metabolizing enzymes and transporters. Elevated levels of drug-metabolizing enzymes and efflux transporters, resulting from CAR activation in various cancers, promote the elimination of chemotherapeutic agents, leading to reduced therapeutic effectiveness and acquired drug resistance. CAR inhibitors, in combination with existing chemotherapeutics, could therefore be used to attenuate multidrug resistance in cancers. Interestingly, all previously reported CAR inverse-agonists are also activators of PXR, rendering them mechanistically counterproductive in tissues where both these xenobiotic receptors are present and active. We used a directed high-throughput screening approach, followed by subsequent mechanistic studies, to identify novel, potent, and specific small-molecule CAR inhibitors that do not activate PXR. We describe here one such inhibitor, CINPA1 (CAR inhibitor not PXR activator 1), capable of reducing CAR-mediated transcription with an IC50 of ∼70 nM. CINPA1 1) is a specific xenobiotic receptor inhibitor and has no cytotoxic effects up to 30 µM; 2) inhibits CAR-mediated gene expression in primary human hepatocytes, where CAR is endogenously expressed; 3) does not alter the protein levels or subcellular localization of CAR; 4) increases corepressor and reduces coactivator interaction with the CAR ligand-binding domain in mammalian two-hybrid assays; and 5) disrupts CAR binding to the promoter regions of target genes in chromatin immunoprecipitation assays. CINPA1 could be used as a novel molecular tool for understanding CAR function. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

  12. Transmembrane α-Helix 2 and 7 Are Important for Small Molecule-Mediated Activation of the GLP-1 Receptor

    DEFF Research Database (Denmark)

    Underwood, Christina Rye; Møller Knudsen, Sanne; Schjellerup Wulff, Birgitte

    2011-01-01

    Glucagon-like peptide-1 (GLP-1) activates the GLP-1 receptor (GLP-1R), which belongs to family B of the G-protein-coupled receptors. We previously identified a selective small molecule ligand, compound 2, that acted as a full agonist and allosteric modulator of GLP-1R. In this study, the structur......Glucagon-like peptide-1 (GLP-1) activates the GLP-1 receptor (GLP-1R), which belongs to family B of the G-protein-coupled receptors. We previously identified a selective small molecule ligand, compound 2, that acted as a full agonist and allosteric modulator of GLP-1R. In this study......, the structurally related small molecule, compound 3, stimulated cAMP production from GLP-1R, but not from the homologous glucagon receptor (GluR). The receptor selectivity encouraged a chimeric receptor approach to identify domains important for compound 3-mediated activation of GLP-1R. A subsegment of the GLP-1R...... transmembrane domain containing TM2 to TM5 was sufficient to transfer compound 3 responsiveness to GluR. Therefore, divergent residues in this subsegment of GLP-1R and GluR are responsible for the receptor selectivity of compound 3. Functional analyses of other chimeric receptors suggested that the existence...

  13. Intracellular recording from a spider vibration receptor.

    Science.gov (United States)

    Gingl, Ewald; Burger, Anna-M; Barth, Friedrich G

    2006-05-01

    The present study introduces a new preparation of a spider vibration receptor that allows intracellular recording of responses to natural mechanical or electrical stimulation of the associated mechanoreceptor cells. The spider vibration receptor is a lyriform slit sense organ made up of 21 cuticular slits located on the distal end of the metatarsus of each walking leg. The organ is stimulated when the tarsus receives substrate vibrations, which it transmits to the organ's cuticular structures, reducing the displacement to about one tenth due to geometrical reasons. Current clamp recording was used to record action potentials generated by electrical or mechanical stimuli. Square pulse stimulation identified two groups of sensory cells, the first being single-spike cells which generated only one or two action potentials and the second being multi-spike cells which produced bursts of action potentials. When the more natural mechanical sinusoidal stimulation was applied, differences in adaptation rate between the two cell types remained. In agreement with prior extracellular recordings, both cell types showed a decrease in the threshold tarsus deflection with increasing stimulus frequency. Off-responses to mechanical stimuli have also been seen in the metatarsal organ for the first time.

  14. TAM receptor signaling in development.

    Science.gov (United States)

    Burstyn-Cohen, Tal

    2017-01-01

    TYRO3, AXL and MERTK comprise the TAM family of receptor protein tyrosine kinases. Activated by their ligands, protein S (PROS1) and growth-arrest-specific 6 (GAS6), they mediate numerous cellular functions throughout development and adulthood. Expressed by a myriad of cell types and tissues, they have been implicated in homeostatic regulation of the immune, nervous, vascular, bone and reproductive systems. The loss-of-function of TAM signaling in adult tissues culminates in the destruction of tissue homeostasis and diseased states, while TAM gain-of-function in various tumors promotes cancer phenotypes. Combinatorial ligand-receptor interactions may elicit different molecular and cellular responses. Many of the TAM regulatory functions are essentially developmental, taking place both during embryogenesis and postnatally. This review highlights current knowledge on the role of TAM receptors and their ligands during these developmental processes in the immune, nervous, vascular and reproductive systems.

  15. How calcium makes endocytic receptors attractive

    DEFF Research Database (Denmark)

    Andersen, Christian B F; Moestrup, Søren K

    2014-01-01

    of the receptor. Endosomal acidification and calcium efflux lead to the essential ligand-receptor affinity switch and separation. Recent data, including crystal structures of receptor-ligand complexes, now reveal how calcium, in different types of domain scaffolds, functions in a common way as a removable...... 'lynchpin' that stabilizes favorable positioning of ligand-attractive receptor residues. In addition to explaining how calcium depletion can cause ligand-receptor dissociation, the new data add further insight into how acidification contributes to dissociation through structural changes that affect...... the receptor calcium sites....

  16. Lessons from crystal structures of kainate receptors

    DEFF Research Database (Denmark)

    Møllerud, Stine; Frydenvang, Karla Andrea; Pickering, Darryl S

    2017-01-01

    Kainate receptors belong to the family of ionotropic glutamate receptors. These receptors assemble from five subunits (GluK1-5) into tetrameric ion channels. Kainate receptors are located at both pre- and postsynaptic membranes in the central nervous system where they contribute to excitatory...... synaptic transmission and modulate network excitability by regulating neurotransmitter release. Dysfunction of kainate receptors has been implicated in several neurological disorders such as epilepsy, schizophrenia and depression. Here we provide a review on the current understanding of kainate receptor...

  17. Distinct phosphotyrosines on a growth factor receptor bind to specific molecules that mediate different signaling pathways.

    Science.gov (United States)

    Fantl, W J; Escobedo, J A; Martin, G A; Turck, C W; del Rosario, M; McCormick, F; Williams, L T

    1992-05-01

    The receptor for platelet-derived growth factor (PDGF) binds two proteins containing SH2 domains, GTPase activating protein (GAP) and phosphatidylinositol 3-kinase (PI3-kinase). The sites on the receptor that mediate this interaction were identified by using phosphotyrosine-containing peptides representing receptor sequences to block specifically binding of either PI3-kinase or GAP. These results suggested that PI3-kinase binds two phosphotyrosine residues, each located in a 5 aa motif with an essential methionine at the fourth position C-terminal to the tyrosine. Point mutations at these sites caused a selective elimination of PI3-kinase binding and loss of PDGF-stimulated DNA synthesis. Mutation of the binding site for GAP prevented the receptor from associating with or phosphorylating GAP, but had no effect on PI3-kinase binding and little effect on DNA synthesis. Therefore, GAP and PI3-kinase interact with the receptor by binding to different phosphotyrosine-containing sequence motifs.

  18. The GPRC6A Receptor displays Constitutive Internalization and Sorting to the Slow Recycling Pathway

    DEFF Research Database (Denmark)

    Jacobsen, Stine Engesgaard; Ammendrup-Johnsen, Ina; Jansen, Anna Mai

    2017-01-01

    The class C G protein-coupled receptor GPRC6A is a putative nutrient sensing receptor and represents a possible new drug target in metabolic disorders. However, the specific physiological role of this receptor has yet to be identified, and the mechanisms regulating its activity and cell surface...... availability also remain enigmatic. In the present study, we investigated the trafficking properties of GPRC6A by use of both a classical antibody feeding internalization assay in which cells were visualized using confocal microscopy and a novel internalization assay that is based on real-time measurements...... slow recycling pathway, which may be responsible for ensuring a persistent pool of GPRC6A receptors at the cell surface despite chronic agonist exposure. Distinct trafficking pathways have been reported for several of the class C receptors, and our results thus substantiate that non...

  19. A meta-analysis of genome-wide association studies of breast cancer identifies two novel susceptibility loci at 6q14 and 20q11

    NARCIS (Netherlands)

    Siddiq, Afshan; Couch, Fergus J.; Chen, Gary K.; Lindström, Sara; Eccles, Diana; Millikan, Robert C.; Michailidou, Kyriaki; Stram, Daniel O.; Beckmann, Lars; Rhie, Suhn Kyong; Ambrosone, Christine B.; Aittomäki, Kristiina; Amiano, Pilar; Apicella, Carmel; Baglietto, Laura; Bandera, Elisa V.; Beckmann, Matthias W.; Berg, Christine D.; Bernstein, Leslie; Blomqvist, Carl; Brauch, Hiltrud; Brinton, Louise; Bui, Quang M.; Buring, Julie E.; Buys, Saundra S.; Campa, Daniele; Carpenter, Jane E.; Chasman, Daniel I.; Chang-Claude, Jenny; Chen, Constance; Clavel-Chapelon, Françoise; Cox, Angela; Cross, Simon S.; Czene, Kamila; Deming, Sandra L.; Diasio, Robert B.; Diver, W. Ryan; Dunning, Alison M.; Durcan, Lorraine; Ekici, Arif B.; Fasching, Peter A.; Feigelson, Heather Spencer; Fejerman, Laura; Figueroa, Jonine D.; Fletcher, Olivia; Flesch-Janys, Dieter; Gaudet, Mia M.; Gerty, Susan M.; Rodriguez-Gil, Jorge L.; Giles, Graham G.; van Gils, Carla H.; Godwin, Andrew K.; Graham, Nikki; Greco, Dario; Hall, Per; Hankinson, Susan E.; Hartmann, Arndt; Hein, Rebecca; Heinz, Judith; Hoover, Robert N.; Hopper, John L.; Hu, Jennifer J.; Huntsman, Scott; Ingles, Sue A.; Irwanto, Astrid; Isaacs, Claudine; Jacobs, Kevin B.; John, Esther M.; Justenhoven, Christina; Kaaks, Rudolf; Kolonel, Laurence N.; Coetzee, Gerhard A.; Lathrop, Mark; Le Marchand, Loic; Lee, Adam M.; Lee, I.-Min; Lesnick, Timothy; Lichtner, Peter; Liu, Jianjun; Lund, Eiliv; Makalic, Enes; Martin, Nicholas G.; McLean, Catriona A.; Meijers-Heijboer, Hanne; Meindl, Alfons; Miron, Penelope; Monroe, Kristine R.; Montgomery, Grant W.; Müller-Myhsok, Bertram; Nickels, Stefan; Nyante, Sarah J.; Olswold, Curtis; Overvad, Kim; Palli, Domenico; Park, Daniel J.; Palmer, Julie R.; Pathak, Harsh; Peto, Julian; Pharoah, Paul; Rahman, Nazneen; Rivadeneira, Fernando; Schmidt, Daniel F.; Schmutzler, Rita K.; Slager, Susan; Southey, Melissa C.; Stevens, Kristen N.; Sinn, Hans-Peter; Press, Michael F.; Ross, Eric; Riboli, Elio; Ridker, Paul M.; Schumacher, Fredrick R.; Severi, Gianluca; dos Santos Silva, Isabel; Stone, Jennifer; Sund, Malin; Tapper, William J.; Thun, Michael J.; Travis, Ruth C.; Turnbull, Clare; Uitterlinden, Andre G.; Waisfisz, Quinten; Wang, Xianshu; Wang, Zhaoming; Weaver, Joellen; Schulz-Wendtland, Rüdiger; Wilkens, Lynne R.; van den Berg, David; Zheng, Wei; Ziegler, Regina G.; Ziv, Elad; Nevanlinna, Heli; Easton, Douglas F.; Hunter, David J.; Henderson, Brian E.; Chanock, Stephen J.; Garcia-Closas, Montserrat; Kraft, Peter; Haiman, Christopher A.; Vachon, Celine M.

    2012-01-01

    Genome-wide association studies (GWAS) of breast cancer defined by hormone receptor status have revealed loci contributing to susceptibility of estrogen receptor (ER)-negative subtypes. To identify additional genetic variants for ER-negative breast cancer, we conducted the largest meta-analysis of

  20. Increased renin production in mice with deletion of peroxisome proliferator-activated receptor-gamma in juxtaglomerular cells

    DEFF Research Database (Denmark)

    Desch, Michael; Schreiber, Andrea; Schweda, Frank

    2010-01-01

    We recently found that endogenous (free fatty acids) and pharmacological (thiazolidinediones) agonists of nuclear receptor Peroxisome proliferator-activated receptor (PPAR)gamma stimulate renin transcription. In addition, the renin gene was identified as a direct target of PPARgamma. The mouse re...

  1. A novel activating chicken IgY FcR is related to leukocyte receptor complex (LRC)

    NARCIS (Netherlands)

    Viertlboeck, B.C.; Schmitt, R.; Hanczaruk, M.A.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Gobel, T.W.

    2009-01-01

    FcRs have multifaceted roles in the immune system. Chicken FcRs were demonstrated on macrophages decades ago; however, only recently the chicken Ig-like receptor AB1, encoded in the leukocyte receptor complex, was molecularly identified as a high-affinity FcR. The present study was initiated to

  2. FGF receptor genes and breast cancer susceptibility

    DEFF Research Database (Denmark)

    Agarwal, D; Pineda, S; Michailidou, K

    2014-01-01

    Background:Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying...... genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium.Methods:Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry......, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression.Results:Little evidence of association with breast cancer risk...

  3. Structural determinants for antagonist pharmacology that distinguish the rho1 GABAC receptor from GABAA receptors.

    Science.gov (United States)

    Zhang, Jianliang; Xue, Fenqin; Chang, Yongchang

    2008-10-01

    GABA receptor (GABAR) types C (GABACR) and A (GABAAR) are both GABA-gated chloride channels that are distinguished by their distinct competitive antagonist properties. The structural mechanism underlying these distinct properties is not well understood. In this study, using previously identified binding residues as a guide, we made individual or combined mutations of nine binding residues in the rho1 GABACR subunit to their counterparts in the alpha1beta2gamma2 GABAAR or reverse mutations in alpha1 or beta2 subunits. The mutants were expressed in Xenopus laevis oocytes and tested for sensitivities of GABA-induced currents to the GABAA and GABAC receptor antagonists. The results revealed that bicuculline insensitivity of the rho1 GABACR was mainly determined by Tyr106, Phe138 and Phe240 residues. Gabazine insensitivity of the rho1 GABACR was highly dependent on Tyr102, Tyr106, and Phe138. The sensitivity of the rho1 GABACR to 3-aminopropyl-phosphonic acid and its analog 3-aminopropyl-(methyl)phosphinic acid mainly depended on residues Tyr102, Val140, FYS240-242, and Phe138. Thus, the residues Tyr102, Tyr106, Phe138, and Phe240 in the rho1 GABACR are major determinants for its antagonist properties distinct from those in the GABAAR. In addition, Val140 in the GABACR contributes to 3-APA binding. In conclusion, we have identified the key structural elements underlying distinct antagonist properties for the GABACR. The mechanistic insights were further extended and discussed in the context of antagonists docking to the homology models of GABAA or GABAC receptors.

  4. Identification of a receptor for extracellular renalase.

    Directory of Open Access Journals (Sweden)

    Ling Wang

    Full Text Available An increased risk for developing essential hypertension, stroke and diabetes is associated with single nucleotide gene polymorphisms in renalase, a newly described secreted flavoprotein with oxidoreductase activity. Gene deletion causes hypertension, and aggravates acute ischemic kidney (AKI and cardiac injury. Independent of its intrinsic enzymatic activities, extracellular renalase activates MAPK signaling and prevents acute kidney injury (AKI in wild type (WT mice. Therefore, we sought to identity the receptor for extracellular renalase.RP-220 is a previously identified, 20 amino acids long renalase peptide that is devoid of any intrinsic enzymatic activity, but it is equally effective as full-length recombinant renalase at protecting against toxic and ischemic injury. Using biotin transfer studies with RP-220 in the human proximal tubular cell line HK-2 and protein identification by mass spectrometry, we identified PMCA4b as a renalase binding protein. This previously characterized plasma membrane ATPase is involved in cell signaling and cardiac hypertrophy. Co-immunoprecipitation and co-immunolocalization confirmed protein-protein interaction between endogenous renalase and PMCA4b. Down-regulation of endogenous PMCA4b expression by siRNA transfection, or inhibition of its enzymatic activity by the specific peptide inhibitor caloxin1b each abrogated RP-220 dependent MAPK signaling and cytoprotection. In control studies, these maneuvers had no effect on epidermal growth factor mediated signaling, confirming specificity of the interaction between PMCA4b and renalase.PMCA4b functions as a renalase receptor, and a key mediator of renalase dependent MAPK signaling.

  5. Pharmacodynamics of selective androgen receptor modulators.

    Science.gov (United States)

    Yin, Donghua; Gao, Wenqing; Kearbey, Jeffrey D; Xu, Huiping; Chung, Kiwon; He, Yali; Marhefka, Craig A; Veverka, Karen A; Miller, Duane D; Dalton, James T

    2003-03-01

    The present study aimed to identify selective androgen receptor modulators (SARMs) with in vivo pharmacological activity. We examined the in vitro and in vivo pharmacological activity of four chiral, nonsteroidal SARMs synthesized in our laboratories. In the in vitro assays, these compounds demonstrated moderate to high androgen receptor (AR) binding affinity, with K(i) values ranging from 4 to 37 nM, and three of the compounds efficaciously stimulated AR-mediated reporter gene expression. The compounds were then administered subcutaneously to castrated rats to appraise their in vivo pharmacological activity. Androgenic activity was evaluated by the ability of these compounds to maintain the weights of prostate and seminal vesicle, whereas levator ani muscle weight was used as a measure of anabolic activity. The maximal response (E(max)) and dose for half-maximal effect (ED(50)) were determined for each compound and compared with that observed for testosterone propionate (TP). Compounds S-1 and S-4 demonstrated in vivo androgenic and anabolic activity, whereas compounds S-2 and S-3 did not. The activities of S-1 and S-4 were tissue-selective in that both compounds stimulated the anabolic organs more than the androgenic organs. These two compounds were less potent and efficacious than TP in androgenic activity, but their anabolic activity was similar to or greater than that of TP. Neither S-1 nor S-4 caused significant luteinizing hormone or follicle stimulating hormone suppression at doses near the ED(50) value. Thus, compounds S-1 and S-4 were identified as SARMs with potent and tissue-selective in vivo pharmacological activity, and represent the first members of a new class of SARMs with selective anabolic effects.

  6. Taste Receptor Signaling-- From Tongues to Lungs

    Science.gov (United States)

    Kinnamon, Sue C.

    2013-01-01

    Taste buds are the transducing endorgans of gustation. Each taste bud comprises 50–100 elongated cells, which extend from the basal lamina to the surface of the tongue, where their apical microvilli encounter taste stimuli in the oral cavity. Salts and acids utilize apically located ion channels for transduction, while bitter, sweet and umami (glutamate) stimuli utilize G protein coupled receptors (GPCRs) and second messenger signaling mechanisms. This review will focus on GPCR signaling mechanisms. Two classes of taste GPCRs have been identified, the T1Rs for sweet and umami (glutamate) stimuli, and the T2Rs for bitter stimuli. These low affinity GPCRs all couple to the same downstream signaling effectors that include Gβγ activation of PLCβ2, IP3-mediated release of Ca2+ from intracellular stores, and Ca2+-dependent activation of the monovalent selective cation channel, TrpM5. These events lead to membrane depolarization, action potentials, and release of ATP as a transmitter to activate gustatory afferents. The Gα subunit, α-gustducin, activates a phosphodiesterase to decrease intracellular cAMP levels, although the precise targets of cAMP have not been identified. With the molecular identification of the taste GPCRs, it has become clear that taste signaling is not limited to taste buds, but occurs in many cell types of the airways. These include solitary chemosensory cells, ciliated epithelial cells, and smooth muscle cells. Bitter receptors are most abundantly expressed in the airways, where they respond to irritating chemicals and promote protective airway reflexes, utilizing the same downstream signaling effectors as taste cells. PMID:21481196

  7. A nuclear-receptor-dependent phosphatidylcholine pathway with antidiabetic effects.

    Science.gov (United States)

    Lee, Jae Man; Lee, Yoon Kwang; Mamrosh, Jennifer L; Busby, Scott A; Griffin, Patrick R; Pathak, Manish C; Ortlund, Eric A; Moore, David D

    2011-05-25

    Nuclear hormone receptors regulate diverse metabolic pathways and the orphan nuclear receptor LRH-1 (also known as NR5A2) regulates bile acid biosynthesis. Structural studies have identified phospholipids as potential LRH-1 ligands, but their functional relevance is unclear. Here we show that an unusual phosphatidylcholine species with two saturated 12 carbon fatty acid acyl side chains (dilauroyl phosphatidylcholine (DLPC)) is an LRH-1 agonist ligand in vitro. DLPC treatment induces bile acid biosynthetic enzymes in mouse liver, increases bile acid levels, and lowers hepatic triglycerides and serum glucose. DLPC treatment also decreases hepatic steatosis and improves glucose homeostasis in two mouse models of insulin resistance. Both the antidiabetic and lipotropic effects are lost in liver-specific Lrh-1 knockouts. These findings identify an LRH-1 dependent phosphatidylcholine signalling pathway that regulates bile acid metabolism and glucose homeostasis.

  8. The lactate receptor, G-protein-coupled receptor 81/hydroxycarboxylic acid receptor 1

    DEFF Research Database (Denmark)

    Morland, Cecilie; Lauritzen, Knut Huso; Puchades, Maja

    2015-01-01

    We have proposed that lactate is a “volume transmitter” in the brain and underpinned this by showing that the lactate receptor, G-protein-coupled receptor 81 (GPR81, also known as HCA1 or HCAR1), which promotes lipid storage in adipocytes, is also active in the mammalian brain. This includes......, energy metabolism, and energy substrate availability, including a glucose- and glycogen-saving response. HCAR1 may contribute to optimizing the cAMP concentration. For instance, in the prefrontal cortex, excessively high cAMP levels are implicated in impaired cognition in old age, fatigue, stress...

  9. Trace amine-associated receptor 1-Family archetype or iconoclast?

    Science.gov (United States)

    Grandy, David K

    2007-12-01

    Interest has recently been rekindled in receptors that are activated by low molecular weight, noncatecholic, biogenic amines that are typically found as trace constituents of various vertebrate and invertebrate tissues and fluids. The timing of this resurgent focus on receptors activated by the "trace amines" (TA) beta-phenylethylamine (PEA), tyramine (TYR), octopamine (OCT), synephrine (SYN), and tryptamine (TRYP) is the direct result of 2 publications that appeared in 2001 describing the cloning of a novel G protein-coupled receptor (GPCR) referred to by their discoverers Borowsky et al. as TA1 and Bunzow et al. as TA receptor 1 (TAR1). When heterologously expressed in Xenopus laevis oocytes and various eukaryotic cell lines, recombinant rodent and human TAR dose-dependently couple to the stimulation of adenosine 3',5'-monophosphate (cAMP) production. Structure-activity profiling based on this functional response has revealed that in addition to the TA, other biologically active compounds containing a 2-carbon aliphatic side chain linking an amino group to at least 1 benzene ring are potent and efficacious TA receptor agonists with amphetamine (AMPH), methamphetamine, 3-iodothyronamine, thyronamine, and dopamine (DA) among the most notable. Almost 100 years after the search for TAR began, numerous TA1/TAR1-related sequences, now called TA-associated receptors (TAAR), have been identified in the genome of every species of vertebrate examined to date. Consequently, even though heterologously expressed TAAR1 fits the pharmacological criteria established for a bona fide TAR, a major challenge for those working in the field is to discern the in vivo pharmacology and physiology of each purported member of this extended family of GPCR. Only then will it be possible to establish whether TAAR1 is the family archetype or an iconoclast.

  10. Role of sex steroid receptors in pathobiology of hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Mamta Kalra; Jary Mayes; Senait Assefa; Anil K Kaul; Rashmi Kaul

    2008-01-01

    The striking gender disparity observed in the incidence of hepatocellular carcinoma (HCC) suggests an important role of sex hormones in HCC pathogenesis. Though the studies began as early as in 1980s, the precise role of sex hormones and the significance of their receptors in HCC still remain poorly understood and perhaps contribute to current controversies about the potential use of hormonal therapy in HCC. A comprehensive review of the existing literature revealed several shortcomings associated with the studies on estrogen receptor (ER) and androgen receptor (AR) in normal liver and HCC. These shortcomings include the use of less sensitive receptor ligand binding assays and immunohistochemistry studies for ERα alone until 1996 when ERβ isoform was identified. The animal models of HCC utilized for studies were primarily based on chemical-induced hepatocarcinogenesis with less similarity to virus-induced HCC pathogenesis. However, recent in vitro studies in hepatoma cells provide newer insights for hormonal regulation of key cellular processes including interaction of ER and AR with viral proteins. In light of the above facts, there is an urgent need for a detailed investigation of sex hormones and their receptors in normal liver and HCC. In this review, we systematically present the information currently available on androgens, estrogens and their receptors in normal liver and HCC obtained from in vitro, in vivo experimental models and clinical studies. This information will direct future basic and clinical research to bridge the gap in knowledge to explore the therapeutic potential of hormonal therapy in HCC. 2008 The WJG Press. All rights reserved.

  11. Role of a Ubiquitously Expressed Receptor in the Vertebrate Olfactory System

    Science.gov (United States)

    DeMaria, Shannon; Berke, Allison P.; Van Name, Eric; Heravian, Anisa; Ferreira, Todd

    2013-01-01

    Odorant cues are recognized by receptors expressed on olfactory sensory neurons, the primary sensory neurons of the olfactory epithelium. Odorant receptors typically obey the “one receptor, one neuron” rule, in which the receptive field of the olfactory neuron is determined by the singular odorant receptor that it expresses. Odor-evoked receptor activity across the population of olfactory neurons is then interpreted by the brain to identify the molecular nature of the odorant stimulus. In the present study, we characterized the properties of a C family G-protein-coupled receptor that, unlike most other odorant receptors, is expressed in a large population of microvillous sensory neurons in the zebrafish olfactory epithelium and the mouse vomeronasal organ. We found that this receptor, OlfCc1 in zebrafish and its murine ortholog Vmn2r1, is a calcium-dependent, low-sensitivity receptor specific for the hydrophobic amino acids isoleucine, leucine, and valine. Loss-of-function experiments in zebrafish embryos demonstrate that OlfCc1 is required for olfactory responses to a diverse mixture of polar, nonpolar, acidic, and basic amino acids. OlfCc1 was also found to promote localization of other OlfC receptor family members to the plasma membrane in heterologous cells. Together, these results suggest that the broadly expressed OlfCc1 is required for amino acid detection by the olfactory system and suggest that it plays a role in the function and/or intracellular trafficking of other olfactory and vomeronasal receptors with which it is coexpressed. PMID:24048853

  12. DESENSITIZATION PROPERTIES OF P2X3 RECEPTORS SHAPING PAIN SIGNALLING

    Directory of Open Access Journals (Sweden)

    Rashid eGiniatullin

    2013-12-01

    Full Text Available ATP-gated P2X3 receptors are mostly expressed by nociceptive sensory neurons and participate in transduction of pain signals. P2X3 receptors show a combination of fast desensitization onset and slow recovery. Moreover, even low nanomolar agonist concentrations unable to evoke a response, can induce desensitization via a phenomenon called ‘high affinity desensitization’. We have also observed that recovery from desensitization is agonist-specific and can range from seconds to minutes. The recovery process displays unusually high temperature dependence. Likewise, recycling of P2X3 receptors in peri-membrane regions shows unexpectedly large temperature sensitivity. By applying kinetic modeling, we have previously shown that desensitization characteristics of P2X3 receptor are best explained with a cyclic model of receptor operation involving three agonist molecules binding a single receptor and that desensitization is primarily developing from the open receptor state. Mutagenesis experiments suggested that desensitization depends on a certain conformation of the ATP binding pocket and on the structure of the transmembrane domains forming the ion pore. Further molecular determinants of desensitization have been identified by mutating the intracellular N- and C-termini of P2X3 receptor. Unlike other P2X receptors, the P2X3 subtype is facilitated by extracellular calcium that acts via specific sites in the ectodomain neighboring the ATP binding pocket. Thus, substitution of serine275 in this region (called ‘left flipper’ converts the natural facilitation induced by extracellular calcium to receptor inhibition. Given such their strategic location in nociceptive neurons and unique desensitization properties, P2X3 receptors represent an attractive target for development of new analgesic drugs via promotion of desensitization aimed at suppressing chronic pain.

  13. Mechanism of action of the insecticides, lindane and fipronil, on glycine receptor chloride channels.

    Science.gov (United States)

    Islam, Robiul; Lynch, Joseph W

    2012-04-01

    Docking studies predict that the insecticides, lindane and fipronil, block GABA(A) receptors by binding to 6' pore-lining residues. However, this has never been tested at any Cys-loop receptor. The neurotoxic effects of these insecticides are also thought to be mediated by GABA(A) receptors, although a recent morphological study suggested glycine receptors mediated fipronil toxicity in zebrafish. Here we investigated whether human α1, α1β, α2 and α3 glycine receptors were sufficiently sensitive to block by either compound as to represent possible neurotoxicity targets. We also investigated the mechanisms by which lindane and fipronil inhibit α1 glycine receptors. Glycine receptors were recombinantly expressed in HEK293 cells and insecticide effects were studied using patch-clamp electrophysiology. Both compounds completely inhibited all tested glycine receptor subtypes with IC(50) values ranging from 0.2-2 µM, similar to their potencies at vertebrate GABA(A) receptors. Consistent with molecular docking predictions, both lindane and fipronil interacted with 6' threonine residues via hydrophobic interactions and hydrogen bonds. In contrast with predictions, we found no evidence for lindane interacting at the 2' level. We present evidence for fipronil binding in a non-blocking mode in the anaesthetic binding pocket, and for lindane as an excellent pharmacological tool for identifying the presence of β subunits in αβ heteromeric glycine receptors. This study implicates glycine receptors as novel vertebrate toxicity targets for fipronil and lindane. Furthermore, lindane interacted with pore-lining 6' threonine residues, whereas fipronil may have both pore and non-pore binding sites. © 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.

  14. Stability of solubilized benzodiazepine receptors

    NARCIS (Netherlands)

    Janssen, M.J; Ensing, K; de Zeeuw, R.A

    1997-01-01

    According to the observations of other researchers, benzodiazepine receptors solubilized with sodium deoxycholate are unstable, but stability can be improved by exchanging deoxycholate for Triton X-100. In our experiments we conclude that the choice of detergent is not the restrictive factor for the

  15. Serum transferrin receptor in polycythemia.

    Science.gov (United States)

    Manteiga, R; Remacha, A F; Sardà, M P; Ubeda, J

    1998-10-01

    We measured serum transferrin receptor (sTfR) levels in 22 patients with polycythemia vera and in 26 cases of secondary polycythemia. In our study, raised sTfR levels in both polycythemia groups were related to iron deficiency.

  16. Pharmacological approach of the receptors

    International Nuclear Information System (INIS)

    Puech, A.J.

    1989-01-01

    This paper explains the three main goals for clinical positron emission tomography (PET) studies: detection of receptor abnormalities in groups of patients to propose therapeutic indication of new ligands; validation of current hypothesis of drug effect; rational clinical drug development specially for dose-finding studies. (H.W.)

  17. Uncompetitive antagonism of AMPA receptors

    DEFF Research Database (Denmark)

    Andersen, Trine F; Tikhonov, Denis B; Bølcho, Ulrik

    2006-01-01

    Philanthotoxins are uncompetitive antagonists of Ca2+-permeable AMPA receptors presumed to bind to the pore-forming region, but a detailed molecular mechanism for this interaction is missing. Here a small library of novel philanthotoxins was designed and synthesized using a solid-phase strategy. ...

  18. Identification of receptors of main sex-pheromone components of three Lepidopteran species.

    Science.gov (United States)

    Mitsuno, Hidefumi; Sakurai, Takeshi; Murai, Masatoshi; Yasuda, Tetsuya; Kugimiya, Soichi; Ozawa, Rika; Toyohara, Haruhiko; Takabayashi, Junji; Miyoshi, Hideto; Nishioka, Takaaki

    2008-09-01

    Male moths discriminate conspecific female-emitted sex pheromones. Although the chemical components of sex pheromones have been identified in more than 500 moth species, only three components in Bombyx mori and Heliothis virescens have had their receptors identified. Here we report the identification of receptors for the main sex-pheromone components in three moth species, Plutella xylostella, Mythimna separata and Diaphania indica. We cloned putative sex-pheromone receptor genes PxOR1, MsOR1 and DiOR1 from P. xylostella, M. separata and D. indica, respectively. Each of the three genes was exclusively expressed with an Or83b orthologous gene in male olfactory receptor neurons (ORNs) that are surrounded by supporting cells expressing pheromone-binding-protein (PBP) genes. By two-electrode voltage-clamp recording, we tested the ligand specificity of Xenopus oocytes co-expressing PxOR1, MsOR1 or DiOR1 with an OR83b family protein. Among the seven sex-pheromone components of the three moth species, the oocytes dose-dependently responded only to the main sex-pheromone component of the corresponding moth species. In our study, PBPs were not essential for ligand specificity of the receptors. On the phylogenetic tree of insect olfactory receptors, the six sex-pheromone receptors identified in the present and previous studies are grouped in the same subfamily but have no relation with the taxonomy of moths. It is most likely that sex-pheromone receptors have randomly evolved from ancestral sex-pheromone receptors before the speciation of moths and that their ligand specificity was modified by mutations of local amino acid sequences after speciation.

  19. NMDA receptors and memory encoding.

    Science.gov (United States)

    Morris, Richard G M

    2013-11-01

    It is humbling to think that 30 years have passed since the paper by Collingridge, Kehl and McLennan showing that one of Jeff Watkins most interesting compounds, R-2-amino-5-phosphonopentanoate (d-AP5), blocked the induction of long-term potentiation in vitro at synapses from area CA3 of the hippocampus to CA1 without apparent effect on baseline synaptic transmission (Collingridge et al., 1983). This dissociation was one of the key triggers for an explosion of interest in glutamate receptors, and much has been discovered since that collectively contributes to our contemporary understanding of glutamatergic synapses - their biophysics and subunit composition, of the agonists and antagonists acting on them, and their diverse functions in different networks of the brain and spinal cord. It can be fairly said that Collingridge et al.'s (1983) observation was the stimulus that has led, on the one hand, to structural biological work at the atomic scale describing the key features of NMDA receptors that enables their coincidence function to happen; and, on the other, to work with whole animals investigating the contributions that calcium signalling via this receptor can have on rhythmical activities controlled by spinal circuits, memory encoding in the hippocampus (the topic of this article), visual cortical plasticity, sensitization in pain, and other functions. In this article, I lay out how my then interest in long-term potentiation (LTP) as a model of memory enabled me to recognise the importance of Collingridge et al.'s discovery - and how I and my colleagues endeavoured to take things forward in the area of learning and memory. This is in some respects a personal story, and I tell it as such. The idea that NMDA receptor activation is essential for memory encoding, though not for storage, took time to develop and to be accepted. Along the way, there have been confusions, challenges, and surprises surrounding the idea that activation of NMDA receptors can

  20. Ror receptor tyrosine kinases: orphans no more

    OpenAIRE

    Green, Jennifer L.; Kuntz, Steven G.; Sternberg, Paul W.

    2008-01-01

    Receptor tyrosine kinase-like orphan receptor (Ror) proteins are a conserved family of tyrosine kinase receptors that function in developmental processes including skeletal and neuronal development, cell movement and cell polarity. Although Ror proteins were originally named because the associated ligand and signaling pathway were unknown, recent studies in multiple species have now established that Ror proteins are Wnt receptors. Depending on the cellular context, Ror proteins can either act...

  1. Benzodiazepine receptor antagonists for hepatic encephalopathy

    DEFF Research Database (Denmark)

    Als-Nielsen, B; Gluud, L L; Gluud, C

    2004-01-01

    Hepatic encephalopathy may be associated with accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition. Benzodiazepine receptor antagonists may have a beneficial effect on patients with hepatic encephalopathy.......Hepatic encephalopathy may be associated with accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition. Benzodiazepine receptor antagonists may have a beneficial effect on patients with hepatic encephalopathy....

  2. Identification of a murine cysteinyl leukotriene receptor by expression in Xenopus laevis oocytes

    DEFF Research Database (Denmark)

    Mollerup, Jens; Jørgensen, Sune T.; Hougaard, Charlotte

    2001-01-01

    We report the identification of an EST encoding a murine cysteinyl leukotriene (mCysLT) receptor. LTD4, LTC4 and LTE4 but not LTB4 or various nucleotides activated Ca2+-evoked Cl- currents in mCysLT1 expressing Xenopus laevis oocytes. The response to LTD4 was blocked by MK-571, reduced by pretrea...... by pretreatment with pertussis toxin (PTX), and was partly dependent on extracellular Ca2+. The identified murine CysLT1 receptor differs from the hCysLT1 receptor with regard to PTX sensitivity, receptor-mediated Ca2+ influx, and antagonist sensitivity....

  3. Melatonin receptors: Current status, facts, and hypothesis

    International Nuclear Information System (INIS)

    Stankov, B.; Reiter, R.J.

    1990-01-01

    Great progress has been made in the identification of melatonin binding sites, commonly identified as melatonin receptors by many authors, in recent years. The bulk of these studies have investigated the sites using either autoradiographic and biochemical techniques with the majority of the experiments being done on the rat, Djungarian and Syrian hamster, and sheep, although human tissue has also been employed. Many of the studies have identified melatonin binding in the central nervous system with either tritium- or iodine-labelled ligands. The latter ligand seems to provide the most reproducible and consistent data. Of the central neural tissues examined, the suprachiasmatic nuclei are most frequently mentioned as a location for melatonin binding sites although binding seems to be widespread in the brain. The other tissue that has been prominently mentioned as a site for melatonin binding is the pars tuberalis of the anterior pituitary gland. There may be time-dependent variations in melatonin binding densities in both neural and pituitary gland tissue. Very few attempts have been made to identify melatonin binding outside of the central nervous system despite the widespread actions of melatonin. Preliminary experiments have been carried out on the intracellular second messengers which mediate the actions of melatonin

  4. The urokinase receptor associated protein (uPARAP/endo180)

    DEFF Research Database (Denmark)

    Engelholm, L H; Nielsen, B S; Danø, K

    2001-01-01

    The urokinase-mediated plasminogen activation system plays a central role in the extracellular proteolytic degradation reactions in cancer invasion. In this review article we discuss a number of recent findings identifying a new cellular receptor protein, uPARAP, that interacts with components of...... and their substrate degradation products and thus may add to the complicated interplay between several cell types in governing restricted tissue degradation....

  5. Synaptic Bistability Due to Nucleation and Evaporation of Receptor Clusters

    KAUST Repository

    Burlakov, V. M.; Emptage, N.; Goriely, A.; Bressloff, P. C.

    2012-01-01

    interacting receptors and is stabilized against clustering by a high nucleation barrier. The other state contains a receptor gas in equilibrium with a large cluster of immobile receptors, which is stabilized by the turnover rate of receptors into and out

  6. Identification of a Novel Recycling Sequence in the C-tail of FPR2/ALX Receptor

    Science.gov (United States)

    Thompson, Dawn; McArthur, Simon; Hislop, James N.; Flower, Roderick J.; Perretti, Mauro

    2014-01-01

    Formyl-peptide receptor type 2 (FPR2; also called ALX because it is the receptor for lipoxin A4) sustains a variety of biological responses relevant to the development and control of inflammation, yet the cellular regulation of this G-protein-coupled receptor remains unexplored. Here we report that, in response to peptide agonist activation, FPR2/ALX undergoes β-arrestin-mediated endocytosis followed by rapid recycling to the plasma membrane. We identify a transplantable recycling sequence that is both necessary and sufficient for efficient receptor recycling. Furthermore, removal of this C-terminal recycling sequence alters the endocytic fate of FPR2/ALX and evokes pro-apoptotic effects in response to agonist activation. This study demonstrates the importance of endocytic recycling in the anti-apoptotic properties of FPR2/ALX and identifies the molecular determinant required for modulation of this process fundamental for the control of inflammation. PMID:25326384

  7. Repeated blockade of mineralocorticoid receptors, but not of glucocorticoid receptors impairs food rewarded spatial learning

    NARCIS (Netherlands)

    Douma, B. R.; Korte, S. M.; Buwalda, B.; La Fleur, S. E.; Bohus, B.; Luiten, P. G.

    1998-01-01

    Corticosteroids from the adrenal cortex influence a variety of behaviours including cognition, learning and memory. These hormones act via two intracellular receptors, the mineralo-corticoid receptor (MR) and the glucocorticoid receptor (GR). These two receptor types display a high concentration and

  8. Repeated blockade of mineralocorticoid receptors, but not of glucocorticoid receptors impairs food rewarded spatial learning

    NARCIS (Netherlands)

    Douma, BRK; Korte, SM; Buwalda, B; la Fleur, SE; Bohus, B; Luiten, PGM

    Corticosteroids from the adrenal cortex influence a variety of behaviours including cognition, learning and memory. These hormones act via two intracellular receptors, the mineralo-corticoid receptor (MR) and the glucocorticoid receptor (GR). These two receptor types display a high concentration and

  9. Melanocortin 1 receptor genotype: an important determinant of the damage response of melanocytes to ultraviolet radiation

    Science.gov (United States)

    Kadekaro, Ana Luisa; Leachman, Sancy; Kavanagh, Renny J.; Swope, Viki; Cassidy, Pamela; Supp, Dorothy; Sartor, Maureen; Schwemberger, Sandy; Babcock, George; Wakamatsu, Kazumasa; Ito, Shosuke; Koshoffer, Amy; Boissy, Raymond E.; Manga, Prashiela; Sturm, Richard A.; Abdel-Malek, Zalfa A.

    2010-01-01

    The melanocortin 1 receptor gene is a main determinant of human pigmentation, and a melanoma susceptibility gene, because its variants that are strongly associated with red hair color increase melanoma risk. To test experimentally the association between melanocortin 1 receptor genotype and melanoma susceptibility, we compared the responses of primary human melanocyte cultures naturally expressing different melanocortin 1 receptor variants to α-melanocortin and ultraviolet radiation. We found that expression of 2 red hair variants abolished the response to α-melanocortin and its photoprotective effects, evidenced by lack of functional coupling of the receptor, and absence of reduction in ultraviolet radiation-induced hydrogen peroxide generation or enhancement of repair of DNA photoproducts, respectively. These variants had different heterozygous effects on receptor function. Microarray data confirmed the observed differences in responses of melanocytes with functional vs. nonfunctional receptor to α-melanocortin and ultraviolet radiation, and identified DNA repair and antioxidant genes that are modulated by α-melanocortin. Our findings highlight the molecular mechanisms by which the melanocortin 1 receptor genotype controls genomic stability of and the mutagenic effect of ultraviolet radiation on human melanocytes.—Kadekaro, A. L., Leachman, S., Kavanagh, R. J., Swope, V., Cassidy, P., Supp, D., Sartor, M., Schwemberger, S., Babcock, G., Wakamatsu, K., Ito, S., Koshoffer, A., Boissy, R. E., Manga, P., Sturm, R. A., Abdel-Malek, Z. A. Melanocortin 1 receptor genotype: an important determinant of the damage response of melanocytes to ultraviolet radiation. PMID:20519635

  10. β2-Adrenergic Receptor Knockout Mice Exhibit A Diabetic Retinopathy Phenotype

    Science.gov (United States)

    Jiang, Youde; Zhang, Qiuhua; Liu, Li; Tang, Jie; Kern, Timothy S.; Steinle, Jena J.

    2013-01-01

    There is considerable evidence from our lab and others for a functional link between β-adrenergic receptor and insulin receptor signaling pathways in retina. Furthermore, we hypothesize that this link may contribute to lesions similar to diabetic retinopathy in that the loss of adrenergic input observed in diabetic retinopathy may disrupt normal anti-apoptotic insulin signaling, leading to retinal cell death. Our studies included assessment of neural retina function (ERG), vascular degeneration, and Müller glial cells (which express only β1 and β2-adrenergic receptor subtypes). In the current study, we produced β2-adrenergic receptor knockout mice to examine this deletion on retinal neurons and vasculature, and to identify specific pathways through which β2-adrenergic receptor modulates insulin signaling. As predicted from our hypothesis, β2-adrenergic receptor knockout mice display certain features similar to diabetic retinopathy. In addition, loss of β2-adrenergic input resulted in an increase in TNFα, a key inhibitor of insulin receptor signaling. Increased TNFα may be associated with insulin-dependent production of the anti-apoptotic factor, Akt. Since the effects occurred in vivo under normal glucose conditions, we postulate that aspects of the diabetic retinopathy phenotype might be triggered by loss of β2-adrenergic receptor signaling. PMID:23894672

  11. Peripheral-type benzodiazepine receptor: a protein of mitochondrial outer membranes utilizing porphyrins as endogenous ligands

    International Nuclear Information System (INIS)

    Snyder, S.H.; Verma, A.; Trifiletti, R.R.

    1987-01-01

    The peripheral-type benzodiazepine receptor is a site identified by its nanomolar affinity for [ 3 H]diazepam, similar to the affinity of diazepam for the central-type benzodiazepine receptor in the brain. The peripheral type benzodiazepine receptor occurs in many peripheral tissues but has discrete localizations as indicated by autoradiographic studies showing uniquely high densities of the receptors in the adrenal cortex and in Leydig cells of the testes. Subcellular localization studies reveal a selective association of the receptors with the outer membrane of mitochondria. Photoaffinity labeling of the mitochondrial receptor with [ 3 H]flunitrazepam reveals two discrete labeled protein bands of 30 and 35 kDa, respectively. The 35-kDa band appears to be identical with the voltage-dependent anion channel protein porin. Fractionation of numerous peripheral tissues reveals a single principal endogenous ligand for the receptor, consisting of porphyrins, which display nanomolar affinity. Interactions of porphyrins with the mitochondrial receptor may clarify its physiological role and account for many pharmacological actions of benzodiazepines

  12. Stimulation of Na+ -K+ -pump currents by epithelial nicotinic receptors in rat colon.

    Science.gov (United States)

    Bader, Sandra; Lottig, Lena; Diener, Martin

    2017-05-01

    Acetylcholine-induced epithelial Cl - secretion is generally thought to be mediated by epithelial muscarinic receptors and nicotinic receptors on secretomotor neurons. However, recent data have shown expression of nicotinic receptors by intestinal epithelium and the stimulation of Cl - secretion by nicotine, in the presence of the neurotoxin, tetrodotoxin. Here, we aimed to identify the transporters activated by epithelial nicotinic receptors and to clarify their role in cholinergic regulation of intestinal ion transport. Ussing chamber experiments were performed, using rat distal colon with intact epithelia. Epithelia were basolaterally depolarized to measure currents across the apical membrane. Apically permeabilized tissue was also used to measure currents across the basolateral membrane in the presence of tetrodotoxin. Nicotine had no effect on currents through Cl - channels in the apical membrane or on currents through K + channels in the apical or the basolateral membrane. Instead, nicotine stimulated the Na + -K + -pump as indicated by Na + -dependency and sensitivity of the nicotine-induced current across the basolateral membrane to cardiac steroids. Effects of nicotine were inhibited by nicotinic receptor antagonists such as hexamethonium and mimicked by dimethyl-4-phenylpiperazinium, a chemically different nicotinic agonist. Simultaneous stimulation of epithelial muscarinic and nicotinic receptors led to a strong potentiation of transepithelial Cl - secretion. These results suggest a novel concept for the cholinergic regulation of transepithelial ion transport by costimulation of muscarinic and nicotinic epithelial receptors and a unique role of nicotinic receptors controlling the activity of the Na + -K + -ATPase. © 2017 The British Pharmacological Society.

  13. Embryonic expression of the transforming growth factor beta ligand and receptor genes in chicken.

    Science.gov (United States)

    Cooley, James R; Yatskievych, Tatiana A; Antin, Parker B

    2014-03-01

    Transforming growth factor-beta (TGFβ) signaling regulates a myriad of biological processes during embryogenesis, in the adult, and during the manifestation of disease. TGFβ signaling is propagated through one of three TGFβ ligands interacting with Type I and Type II receptors, and Type III co-receptors. Although TGFβ signaling is regulated partly by the combinatorial expression patterns of TGFβ receptors and ligands, a comprehensive gene expression analysis has not been published. Here we report the embryonic mRNA expression patterns in chicken embryos of the canonical TGFβ ligands (TGFB1, TGFB2, and TGFB3) and receptors (TGFBR1, TGFBR2, TGFBR3), plus the Activin A receptor, type 1 (ACVR1) and co receptor Endoglin (ENG) that also transduce TGFβ signaling. TGFB ligands and receptors show dynamic and frequently overlapping expression patterns in numerous embryonic cell layers and structures. Integrating expression information identifies combinations of ligands and receptors that are involved in specific developmental processes including somitogenesis, cardiogenesis and vasculogenesis. Copyright © 2013 Wiley Periodicals, Inc.

  14. Intrapulmonary receptors in the Tegu lizard: II. Functional characteristics and localization;.

    Science.gov (United States)

    Scheid, P; Kuhlmann, W D; Fedde, M R

    1977-02-01

    Intrapulmonary receptors identified in the Tegu lizard by single-unit vagal recording (Fedde et al., 1977) were subjected to a number of stimuli and localized within the lung. Some carbon dioxide receptors could follow periodic changes in intrapulmonary CO2 concentrations as rapidly as 1.3 Hz; No oxygen sensitivity was observed with this receptor type, and halothane markedly depressed the discharge frequency. In response to intravenously injected acetazolamide they increased their discharge frequency and became almost totally insensitive to CO2, suggesting molecular per se is not the direct controller of receptor discharge; These receptors show many of the functional characteristics described for those in the avian lung. Afferent activity from both CO2 and mechanoreceptors could be elicited by electrically stimulating the lung surface. The CO2 receptors appeared to be organized in a receptive field covering more than 1 cm2 of lung surface, multiple receptors being innervated by a single afferent fiber. Activity in afferent fibers from mechanoreceptors could be evoked from only one distinct spot on the lung surface. Conduction velocities of afferent fibers from CO2 receptors ranged from 1 to 3 m-sec-1; from mechanoreceptors, from 1.9 to 5.2 m-sec-1.

  15. MT1 melatonin receptors and their role in the oncostatic action of melatonin

    Directory of Open Access Journals (Sweden)

    Karolina Danielczyk

    2009-09-01

    Full Text Available Melatonin, the main hormone produced by the pineal gland, strongly inhibits the growth of cancer cells [i]in vitro[/i] and [i]in vivo[/i]. Some publications indicate that the addition of melatonin to culture medium slows the proliferation of some cancer cell lines. It is also suggested that melatonin used as an adjuvant benefits the effectiveness and tolerance of chemotherapy. The mechanisms of this are not fully understood, but melatonin receptors might be one of the most important elements. Two distinct types of membrane-bound melatonin receptors have been identified in humans: MT1 (Mel1a and MT2 (Mel1b receptors. These subtypes are 60�0homologous at the amino-acid level. MT1 receptors are G-protein-coupled receptors. Through the α subunit of G protein, melatonin receptors stimulate an adenylate cyclase and decrease the level of cAMP. This has a significant influence on cell proliferation and has been confirmed in many tests on different cell lines, such as S-19, B-16 murine melanoma cells, and breast cancer cells. It seems that expression of the MT1 melatonin receptors benefits the efficacy of melatonin treatment. Melatonin and its receptors may provide a promising way to establish new alternative therapeutic approaches in human cancer prevention.

  16. Receptores de progesterona en meningioma.

    Directory of Open Access Journals (Sweden)

    Herminio Ojeda Di Ninno

    1995-04-01

    Full Text Available Objetivo: Determinar la presencia de los receptores de progesterona en meningiomas y su frecuencia mediante la inmunohistoquímica. Material y Métodos: Se analizaron 24 muestras provenientes de pacientes intervenidos quirúrgicamente en el Instituto Nacional de Enfermedades Neoplásicas entre los años 1990 y 1992 con diagnóstico anatomopatológico de meningioma. La determinación de los receptores se hizo mediante una técnica de inmunohistoquímica rápida que permite el estudio de tejidos fijados previamente en parafina. Resultados: De los 24 casos estudiados, nueve resultaron ser positivos en la determinación de receptores de progesterona (37%. Se pudo observar un marcado predominio dentro del grupo femenino quienes constituyeron 8/9 casos positivos. Conclusiones: El empleo de esta reciente técnica de inmunohistoquímica aplicada a tejido de fijado en parafina, nos ha permitido confirmar la presencia de receptores de progesterona en meningiomas con una frecuencia elevada que creemos amerita un estudio más amplio de manera sistemática que incluya la intervención terapéutica mediante el uso de antiprogestágenos, como el Mifepristone o RU 486. De este estudio podrían beneficiarse no sólo pacientes operados recientemente sino aquellos que, intervenidos en el pasado sean detectados como portadores de receptores de progesterona mediante la aplicación de esta novedosa técnica (Rev Med Hered 1995; 6: 121-130.

  17. Imaging of receptors in clinical neurosciences

    NARCIS (Netherlands)

    Korf, J

    This article deals with the question why should one determine receptors in the brain with positron and single photon emission tomography (PET and SPECT, respectively). Radiopharmaceuticals for a wide variety of receptors are available now. Receptors studies with PET and SPECT have thus far focused

  18. Receptor conversion in distant breast cancer metastases

    NARCIS (Netherlands)

    Hoefnagel, L.D.C.

    2013-01-01

    The routine pathological work-up of breast cancer includes the evaluation of the estrogen receptor (ERα), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) which reveals biological information about the tumour as well as provides predictive biomarkers regarding hormonal

  19. Molecular pharmacology of human NMDA receptors

    DEFF Research Database (Denmark)

    Hedegaard, Maiken; Hansen, Kasper Bø; Andersen, Karen Toftegaard

    2012-01-01

    N-methyl-d-aspartate (NMDA) receptors are ionotropic glutamate receptors that mediate excitatory neurotransmission. NMDA receptors are also important drug targets that are implicated in a number of pathophysiological conditions. To facilitate the transition from lead compounds in pre-clinical ani...

  20. Efficient Subgroup C Avian Sarcoma and Leukosis Virus Receptor Activity Requires the IgV Domain of the Tvc Receptor and Proper Display on the Cell Membrane▿

    Science.gov (United States)

    Munguia, Audelia; Federspiel, Mark J.

    2008-01-01

    We recently identified and cloned the receptor for subgroup C avian sarcoma and leukosis viruses [ASLV(C)], i.e., Tvc, a protein most closely related to mammalian butyrophilins, which are members of the immunoglobulin protein family. The extracellular domain of Tvc contains two immunoglobulin-like domains, IgV and IgC, which presumably each contain a disulfide bond important for native function of the protein. In this study, we have begun to identify the functional determinants of Tvc responsible for ASLV(C) receptor activity. We found that the IgV domain of the Tvc receptor is responsible for interacting with the glycoprotein of ASLV(C). Additional experiments demonstrated that a domain was necessary as a spacer between the IgV domain and the membrane-spanning domain for efficient Tvc receptor activity, most likely to orient the IgV domain a proper distance from the cell membrane. The effects on ASLV(C) glycoprotein binding and infection efficiency were also studied by site-directed mutagenesis of the cysteine residues of Tvc as well as conserved amino acid residues of the IgV Tvc domain compared to other IgV domains. In this initial analysis of Tvc determinants important for interacting with ASLV(C) glycoproteins, at least two aromatic amino acid residues in the IgV domain of Tvc, Trp-48 and Tyr-105, were identified as critical for efficient ASLV(C) infection. Interestingly, one or more aromatic amino acid residues have been identified as critical determinants in the other ASLV(A-E) receptors for a proper interaction with ASLV glycoproteins. This suggests that the ASLV glycoproteins may share a common mechanism of receptor interaction with an aromatic residue(s) on the receptor critical for triggering conformational changes in SU that initiate the fusion process required for efficient virus infection. PMID:18768966

  1. Efficient subgroup C avian sarcoma and leukosis virus receptor activity requires the IgV domain of the Tvc receptor and proper display on the cell membrane.

    Science.gov (United States)

    Munguia, Audelia; Federspiel, Mark J

    2008-11-01

    We recently identified and cloned the receptor for subgroup C avian sarcoma and leukosis viruses [ASLV(C)], i.e., Tvc, a protein most closely related to mammalian butyrophilins, which are members of the immunoglobulin protein family. The extracellular domain of Tvc contains two immunoglobulin-like domains, IgV and IgC, which presumably each contain a disulfide bond important for native function of the protein. In this study, we have begun to identify the functional determinants of Tvc responsible for ASLV(C) receptor activity. We found that the IgV domain of the Tvc receptor is responsible for interacting with the glycoprotein of ASLV(C). Additional experiments demonstrated that a domain was necessary as a spacer between the IgV domain and the membrane-spanning domain for efficient Tvc receptor activity, most likely to orient the IgV domain a proper distance from the cell membrane. The effects on ASLV(C) glycoprotein binding and infection efficiency were also studied by site-directed mutagenesis of the cysteine residues of Tvc as well as conserved amino acid residues of the IgV Tvc domain compared to other IgV domains. In this initial analysis of Tvc determinants important for interacting with ASLV(C) glycoproteins, at least two aromatic amino acid residues in the IgV domain of Tvc, Trp-48 and Tyr-105, were identified as critical for efficient ASLV(C) infection. Interestingly, one or more aromatic amino acid residues have been identified as critical determinants in the other ASLV(A-E) receptors for a proper interaction with ASLV glycoproteins. This suggests that the ASLV glycoproteins may share a common mechanism of receptor interaction with an aromatic residue(s) on the receptor critical for triggering conformational changes in SU that initiate the fusion process required for efficient virus infection.

  2. Identification of potent, nonabsorbable agonists of the calcium-sensing receptor for GI-specific administration.

    Science.gov (United States)

    Sparks, Steven M; Spearing, Paul K; Diaz, Caroline J; Cowan, David J; Jayawickreme, Channa; Chen, Grace; Rimele, Thomas J; Generaux, Claudia; Harston, Lindsey T; Roller, Shane G

    2017-10-15

    Modulation of gastrointestinal nutrient sensing pathways provides a promising a new approach for the treatment of metabolic diseases including diabetes and obesity. The calcium-sensing receptor has been identified as a key receptor involved in mineral and amino acid nutrient sensing and thus is an attractive target for modulation in the intestine. Herein we describe the optimization of gastrointestinally restricted calcium-sensing receptor agonists starting from a 3-aminopyrrolidine-containing template leading to the identification of GI-restricted agonist 19 (GSK3004774). Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Cognitive enhancers (Nootropics). Part 1: drugs interacting with receptors. Update 2014.

    Science.gov (United States)

    Froestl, Wolfgang; Muhs, Andreas; Pfeifer, Andrea

    2014-01-01

    Scientists working in the fields of Alzheimer's disease and, in particular, cognitive enhancers are very productive. The review "Cognitive enhancers (nootropics): drugs interacting with receptors" was accepted for publication in July 2012. Since then, new targets for the potential treatment of Alzheimer's disease were identified. This update describes drugs interacting with 42 receptors versus 32 receptors in the first paper. Some compounds progressed in their development, while many others were discontinued. The present review covers the evolution of research in this field through March 2014.

  4. Spatial biomarker of disease and detection of spatial organization of cellular receptors

    Science.gov (United States)

    Salaita, Khalid S.; Nair, Pradeep M.; Das, Debopriya; Gray, Joe W.; Groves, John T.

    2017-07-18

    A signature of a condition of a live cell is established in an assay that allows distribution of the receptors on the cell surface in response to binding a ligand. The receptors can be optically detected and quantified to provide a value for the condition, Test drugs can be screened for therapeutic potential in the assay: a potentially efficacious drug is identified by an ability to modulate an established signature. The receptor distribution signature can be corroborated with an mRNA expression profile of several genes, indicating, for example, metastasis.

  5. Discovery of a novel allosteric modulator of 5-HT3 receptor

    DEFF Research Database (Denmark)

    Trattnig, Sarah M; Harpsøe, Kasper; Thygesen, Sarah B

    2012-01-01

    The ligand-gated ion channels in the Cysloop receptor superfamily mediate the effects of neurotransmitters acetylcholine, serotonin, GABA and glycine. Cysloop receptor signaling is susceptible to modulation by ligands acting through numerous allosteric sites. Here we report the discovery of a novel...... receptor guided by a homology model, PU02 is demonstrated to act through a transmembrane intersubunit site situated in the upper three helical turns of TM2 and TM3 in the (+)subunit and TM1 and TM2 in the (minus)subunit. The Ser248, Leu288, Ile290, Thr294 and Gly306 residues are identified as important...

  6. Receptor Activity-modifying Protein-directed G Protein Signaling Specificity for the Calcitonin Gene-related Peptide Family of Receptors.

    Science.gov (United States)

    Weston, Cathryn; Winfield, Ian; Harris, Matthew; Hodgson, Rose; Shah, Archna; Dowell, Simon J; Mobarec, Juan Carlos; Woodlock, David A; Reynolds, Christopher A; Poyner, David R; Watkins, Harriet A; Ladds, Graham

    2016-10-14

    The calcitonin gene-related peptide (CGRP) family of G protein-coupled receptors (GPCRs) is formed through the association of the calcitonin receptor-like receptor (CLR) and one of three receptor activity-modifying proteins (RAMPs). Binding of one of the three peptide ligands, CGRP, adrenomedullin (AM), and intermedin/adrenomedullin 2 (AM2), is well known to result in a Gα s -mediated increase in cAMP. Here we used modified yeast strains that couple receptor activation to cell growth, via chimeric yeast/Gα subunits, and HEK-293 cells to characterize the effect of different RAMP and ligand combinations on this pathway. We not only demonstrate functional couplings to both Gα s and Gα q but also identify a Gα i component to CLR signaling in both yeast and HEK-293 cells, which is absent in HEK-293S cells. We show that the CGRP family of receptors displays both ligand- and RAMP-dependent signaling bias among the Gα s , Gα i , and Gα q/11 pathways. The results are discussed in the context of RAMP interactions probed through molecular modeling and molecular dynamics simulations of the RAMP-GPCR-G protein complexes. This study further highlights the importance of RAMPs to CLR pharmacology and to bias in general, as well as identifying the importance of choosing an appropriate model system for the study of GPCR pharmacology. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  7. Fc receptor gamma subunit polymorphisms and systemic lupus erythematosus

    International Nuclear Information System (INIS)

    Al-Ansari, Aliya; Ollier, W.E.; Gonzalez-Gay, Miguel A.; Gul, Ahmet; Inanac, Murat; Ordi, Jose; Teh, Lee-Suan; Hajeer, Ali H.

    2004-01-01

    To investigate the possible association between Fc receptor gamma polymorphisms and systemic lupus erythematosus (SLE). We have investigated the full FcR gamma gene for polymorphisms using polymerase chain reaction (PCR)-single strand confirmational polymorphisms and DNA sequencing .The polymorphisms identified were genotype using PCR-restriction fragment length polymorphism. Systemic lupus erythematosus cases and controls were available from 3 ethnic groups: Turkish, Spanish and Caucasian. The study was conducted in the year 2001 at the Arthritis Research Campaign, Epidemiology Unit, Manchester University Medical School, Manchester, United Kingdom. Five single nucleotide polymorphisms were identified, 2 in the promoter, one in intron 4 and, 2 in the 3'UTR. Four of the 5 single nucleotide polymorphisms (SNPs) were relatively common and investigated in the 3 populations. Allele and genotype frequencies of all 4 investigated SNPs were not statistically different cases and controls. fc receptor gamma gene does not appear to contribute to SLE susceptibility. The identified polymorphisms may be useful in investigating other diseases where receptors containing the FcR gamma subunit contribute to the pathology. (author)

  8. Progranulin and the receptor tyrosine kinase EphA2, partners in crime?

    Science.gov (United States)

    Chitramuthu, Babykumari; Bateman, Andrew

    2016-01-01

    Progranulin is a secreted protein with roles in tumorigenesis, inflammation, and neurobiology, but its signaling receptors have remained unclear. In this issue, Neill et al. (2016. J. Cell Biol. https://doi.org/10.1083/jcb.201603079) identify the tyrosine kinase EphA2 as a strong candidate for such a receptor, providing insight into progranulin and EphA2 signaling. PMID:27903608

  9. The G-protein-coupled receptor, GPR84, is important for eye development in Xenopus laevis

    OpenAIRE

    Perry, Kimberly J.; Johnson, Verity R.; Malloch, Erica L.; Fukui, Lisa; Wever, Jason; Thomas, Alvin G.; Hamilton, Paul W.; Henry, Jonathan J.

    2010-01-01

    G-protein-coupled receptors (GPCRs) represent diverse, multifamily groups of cell signaling receptors involved in many cellular processes. We identified Xenopus laevis GPR84 as a member of the A18 subfamily of GPCRs. During development, GPR84 is detected in the embryonic lens placode, differentiating lens fiber cells, retina and cornea. Anti-sense morpholino oligonucleotide-mediated knockdown and RNA rescue experiments demonstrate GPR84’s importance in lens, cornea and retinal development. Ex...

  10. Improved estimation of receptor density and binding rate constants using a single tracer injection and displacement

    International Nuclear Information System (INIS)

    Syrota, A.; Delforge, J.; Mazoyer, B.M.

    1988-01-01

    The possibility of improving receptor model parameter estimation using a displacement experiment in which an excess of an unlabeled ligand (J) is injected after a delay (t D ) following injection of trace amounts of the β + - labeled ligand (J*) is investigated. The effects of varying t D and J/J* on parameter uncertainties are studied in the case of 11 C-MQNB binding to myocardial acetycholine receptor using parameters identified in a dog experiment

  11. Molecular cloning, functional expression, and gene silencing of two Drosophila receptors for the Drosophila neuropeptide pyrokinin-2

    DEFF Research Database (Denmark)

    Rosenkilde, Carina; Cazzamali, Giuseppe; Williamson, Michael

    2003-01-01

    The database of the Drosophila Genome Project contains the sequences of two genes, CG8784 and CG8795, predicted to code for two structurally related G protein-coupled receptors. We have cloned these genes and expressed their coding parts in Chinese hamster ovary cells. We found that both receptors...... can be activated by low concentrations of the Drosophila neuropeptide pyrokinin-2 (CG8784, EC(50) for pyrokinin-2, 1x10(-9)M; CG8795, EC(50) for pyrokinin-2, 5 x 10(-10)M). The precise role of Drosophila pyrokinin-2 (SVPFKPRLamide) in Drosophila is unknown, but in other insects, pyrokinins have...... embryos and first instar larvae. In addition to the two Drosophila receptors, we also identified two probable pyrokinin receptors in the genomic database from the malaria mosquito Anopheles gambiae. The two Drosophila pyrokinin receptors are, to our knowledge, the first invertebrate pyrokinin receptors...

  12. Decreased alternative splicing of estrogen receptor-α mRNA in the Alzheimer's disease brain

    NARCIS (Netherlands)

    Ishunina, Tatjana A.; Swaab, Dick F.

    2012-01-01

    In this study we identified 62 estrogen receptor alpha (ERα) mRNA splice variants in different human brain areas of Alzheimer's disease (AD) and control cases and classified them into 12 groups. Forty-eight of these splice forms were identified for the first time. The distribution of alternatively

  13. Two signaling molecules share a phosphotyrosine-containing binding site in the platelet-derived growth factor receptor.

    Science.gov (United States)

    Nishimura, R; Li, W; Kashishian, A; Mondino, A; Zhou, M; Cooper, J; Schlessinger, J

    1993-11-01

    Autophosphorylation sites of growth factor receptors with tyrosine kinase activity function as specific binding sites for Src homology 2 (SH2) domains of signaling molecules. This interaction appears to be a crucial step in a mechanism by which receptor tyrosine kinases relay signals to downstream signaling pathways. Nck is a widely expressed protein consisting exclusively of SH2 and SH3 domains, the overexpression of which causes cell transformation. It has been shown that various growth factors stimulate the phosphorylation of Nck and its association with autophosphorylated growth factor receptors. A panel of platelet-derived growth factor (PDGF) receptor mutations at tyrosine residues has been used to identify the Nck binding site. Here we show that mutation at Tyr-751 of the PDGF beta-receptor eliminates Nck binding both in vitro and in living cells. Moreover, the Y751F PDGF receptor mutant failed to mediate PDGF-stimulated phosphorylation of Nck in intact cells. A phosphorylated Tyr-751 is also required for binding of phosphatidylinositol-3 kinase to the PDGF receptor. Hence, the SH2 domains of p85 and Nck share a binding site in the PDGF receptor. Competition experiments with different phosphopeptides derived from the PDGF receptor suggest that binding of Nck and p85 is influenced by different residues around Tyr-751. Thus, a single tyrosine autophosphorylation site is able to link the PDGF receptor to two distinct SH2 domain-containing signaling molecules.

  14. Lack of hormone binding in COS-7 cells expressing a mutated growth hormone receptor found in Laron dwarfism.

    Science.gov (United States)

    Edery, M; Rozakis-Adcock, M; Goujon, L; Finidori, J; Lévi-Meyrueis, C; Paly, J; Djiane, J; Postel-Vinay, M C; Kelly, P A

    1993-01-01

    A single point mutation in the growth hormone (GH) receptor gene generating a Phe-->Ser substitution in the extracellular binding domain of the receptor has been identified in one family with Laron type dwarfism. The mutation was introduced by site-directed mutagenesis into cDNAs encoding the full-length rabbit GH receptor and the extracellular domain or binding protein (BP) of the human and rabbit GH receptor, and also in cDNAs encoding the full length and the extracellular domain of the related rabbit prolactin (PRL) receptor. All constructs were transiently expressed in COS-7 cells. Both wild type and mutant full-length rabbit GH and PRL receptors, as well as GH and prolactin BPs (wild type and mutant), were detected by Western blot in cell membranes and concentrated culture media, respectively. Immunofluorescence studies showed that wild type and mutant full-length GH receptors had the same cell surface and intracellular distribution and were expressed with comparable intensities. In contrast, all mutant forms (full-length receptors or BPs), completely lost their modify the synthesis ligand. These results clearly demonstrate that this point mutation (patients with Laron syndrome) does not modify the synthesis or the intracellular pathway of receptor proteins, but rather abolishes ability of the receptor or BP to bind GH and is thus responsible for the extreme GH resistance in these patients. Images PMID:8450064

  15. Origin of secretin receptor precedes the advent of tetrapoda: evidence on the separated origins of secretin and orexin.

    Directory of Open Access Journals (Sweden)

    Janice K V Tam

    Full Text Available At present, secretin and its receptor have only been identified in mammals, and the origin of this ligand-receptor pair in early vertebrates is unclear. In addition, the elusive similarities of secretin and orexin in terms of both structures and functions suggest a common ancestral origin early in the vertebrate lineage. In this article, with the cloning and functional characterization of secretin receptors from lungfish and X. laevis as well as frog (X. laevis and Rana rugulosa secretins, we provide evidence that the secretin ligand-receptor pair has already diverged and become highly specific by the emergence of tetrapods. The secretin receptor-like sequence cloned from lungfish indicates that the secretin receptor was descended from a VPAC-like receptor prior the advent of sarcopterygians. To clarify the controversial relationship of secretin and orexin, orexin type-2 receptor was cloned from X. laevis. We demonstrated that, in frog, secretin and orexin could activate their mutual receptors, indicating their coordinated complementary role in mediating physiological processes in non-mammalian vertebrates. However, among the peptides in the secretin/glucagon superfamily, secretin was found to be the only peptide that could activate the orexin receptor. We therefore hypothesize that secretin and orexin are of different ancestral origins early in the vertebrate lineage.

  16. Some theoretical aspects of hormone receptor determination

    International Nuclear Information System (INIS)

    Sluiter, W.J.

    1981-01-01

    Suitable antisera for determination of hormone receptors are not available for the majority of hormone receptors. Therefore, the determination of hormone receptors is mostly performed in terms of binding capacity for the appropriate hormone, using radioactive hormone labels. Some theoretical aspects of such a receptor determination are discussed including the length of incubation (total or unoccupied receptor concentration), single point or multiple point (Scatchard) analysis (regarding the influence of other specific binders), the correction procedure for non-specific binding and the influence of the circulating hormone level. (Auth.)

  17. [3H]CGP 61594, the first photoaffinity ligand for the glycine site of NMDA receptors

    International Nuclear Information System (INIS)

    Benke, D.; Honer, M.; Mohler, H.; Heckendorn, R.; Pozza, M.F.; Allgeier, H.; Angst, C.

    1999-01-01

    Activation of NMDA receptors requires the presence of glycine as a coagonist which binds to a site that is allosterically linked to the glutamate binding site. To identify the protein constituents of the glycine binding site in situ the photoaffinity label [ 3 H]CGP 61594 was synthesized. In reversible binding assays using crude rat brain membranes, [ 3 H]CGP 61594 labeled with high affinity (K D =23 nM) the glycine site of the NMDA receptor. This was evident from the Scatchard analysis, the displacing potencies of various glycine site ligands and the allosteric modulation of [ 3 H]CGP 61594 binding by ligands of the glutamate and polyamine sites. Electrophysiological experiments in a neocortical slice preparation identified CGP 61594 as a glycine antagonist. Upon UV-irradiation, a protein band of 115 kDa was specifically photolabeled by [ 3 H]CGP 61594 in brain membrane preparations. The photolabeled protein was identified as the NR1 subunit of the NMDA receptor by NR1 subunit-specific immunoaffinity chromatography. Thus, [ 3 H]CGP 61594 is the first photoaffinity label for the glycine site of NMDA receptors. It will serve as a tool for the identification of structural elements that are involved in the formation of the glycine binding domain of NMDA receptors in situ and will thereby complement the mutational analysis of recombinant receptors. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  18. Glutamate metabotropic receptors as targets for drug therapy in epilepsy.

    Science.gov (United States)

    Moldrich, Randal X; Chapman, Astrid G; De Sarro, Giovambattista; Meldrum, Brian S

    2003-08-22

    Metabotropic glutamate (mGlu) receptors have multiple actions on neuronal excitability through G-protein-linked modifications of enzymes and ion channels. They act presynaptically to modify glutamatergic and gamma-aminobutyric acid (GABA)-ergic transmission and can contribute to long-term changes in synaptic function. The recent identification of subtype-selective agonists and antagonists has permitted evaluation of mGlu receptors as potential targets in the treatment of epilepsy. Agonists acting on group I mGlu receptors (mGlu1 and mGlu5) are convulsant. Antagonists acting on mGlu1 or mGlu5 receptors are anticonvulsant against 3,5-dihydroxyphenylglycine (DHPG)-induced seizures and in mouse models of generalized motor seizures and absence seizures. The competitive, phenylglycine mGlu1/5 receptor antagonists generally require intracerebroventricular administration for potent anticonvulsant efficacy but noncompetitive antagonists, e.g., (3aS,6aS)-6a-naphthalen-2-ylmethyl-5-methyliden-hexahydrocyclopenta[c]furan-1-on (BAY36-7620), 2-methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP), and 2-methyl-6-(2-phenylethenyl)pyridine (SIB-1893) block generalized seizures with systemic administration. Agonists acting on group II mGlu receptors (mGlu2, mGlu3) to reduce glutamate release are anticonvulsant, e.g., 2R,4R-aminopyrrolidine-2,4-dicarboxylate [(2R,4R)-APDC], (+)-2-aminobicyclo[3.1.0]hexane-2,6-dicarboxylic acid (LY354740), and (-)-2-oxa-4-aminobicyclo[3.1.0]hexane-4,6-dicarboxylate (LY379268). The classical agonists acting on group III mGlu receptors such as L-(+)-2-amino-4-phosphonobutyric acid, and L-serine-O-phosphate are acutely proconvulsant with some anticonvulsant activity. The more recently identified agonists (R,S)-4-phosphonophenylglycine [(R,S)-PPG] and (S)-3,4-dicarboxyphenylglycine [(S)-3,4-DCPG] and (1S,3R,4S)-1-aminocyclopentane-1,2,4-tricarboxylic acid [ACPT-1] are all anticonvulsant without proconvulsant effects. Studies in animal models of kindling

  19. GRK2 Constitutively Governs Peripheral Delta Opioid Receptor Activity

    Directory of Open Access Journals (Sweden)

    Allison Doyle Brackley

    2016-09-01

    Full Text Available Opioids remain the standard for analgesic care; however, adverse effects of systemic treatments contraindicate long-term administration. While most clinical opioids target mu opioid receptors (MOR, those that target the delta class (DOR also demonstrate analgesic efficacy. Furthermore, peripherally restrictive opioids represent an attractive direction for analgesia. However, opioid receptors including DOR are analgesically incompetent in the absence of inflammation. Here, we report that G protein-coupled receptor kinase 2 (GRK2 naively associates with plasma membrane DOR in peripheral sensory neurons to inhibit analgesic agonist efficacy. This interaction prevents optimal Gβ subunit association with the receptor, thereby reducing DOR activity. Importantly, bradykinin stimulates GRK2 movement away from DOR and onto Raf kinase inhibitory protein (RKIP. protein kinase C (PKC-dependent RKIP phosphorylation induces GRK2 sequestration, restoring DOR functionality in sensory neurons. Together, these results expand the known function of GRK2, identifying a non-internalizing role to maintain peripheral DOR in an analgesically incompetent state.

  20. Identification of agonists for a group of human odorant receptors

    Directory of Open Access Journals (Sweden)

    Daniela eGonzalez-Kristeller

    2015-03-01

    Full Text Available Olfaction plays a critical role in several aspects of the human life. Odorants are detected by hundreds of odorant receptors (ORs which belong to the superfamily of G protein-coupled receptors. These receptors are expressed in the olfactory sensory neurons of the nose. The information provided by the activation of different combinations of ORs in the nose is transmitted to the brain, leading to odorant perception and emotional and behavioral responses. There are ~400 intact human ORs, and to date only a small percentage of these receptors (~10% have known agonists. The determination of the specificity of the human ORs will contribute to a better understanding of how odorants are discriminated by the olfactory system. In this work, we aimed to identify human specific ORs, that is, ORs that are present in humans but absent from other species, and their corresponding agonists. To do this, we first selected 22 OR gene sequences from the human genome with no counterparts in the mouse, rat or dog genomes. Then we used a heterologous expression system to screen a subset of these human ORs against a panel of odorants of biological relevance, including foodborne aroma volatiles. We found that different types of odorants are able to activate some of these previously uncharacterized human ORs.

  1. Immune receptors involved in Streptococcus suis recognition by dendritic cells.

    Directory of Open Access Journals (Sweden)

    Marie-Pier Lecours

    Full Text Available Streptococcus suis is an important swine pathogen and an emerging zoonotic agent of septicemia and meningitis. Knowledge on host immune responses towards S. suis, and strategies used by this pathogen for subversion of these responses is scarce. The objective of this study was to identify the immune receptors involved in S. suis recognition by dendritic cells (DCs. Production of cytokines and expression of co-stimulatory molecules by DCs were shown to strongly rely on MyD88-dependent signaling pathways, suggesting that DCs recognize S. suis and become activated mostly through Toll-like receptor (TLR signaling. Supporting this fact, TLR2(-/- DCs were severely impaired in the release of several cytokines and the surface expression of CD86 and MHC-II. The release of IL-12p70 and CXC10, and the expression of CD40 were found to depend on signaling by both TLR2 and TLR9. The release of IL-23 and CXCL1 were partially dependent on NOD2. Finally, despite the fact that MyD88 signaling was crucial for DC activation and maturation, MyD88-dependent pathways were not implicated in S. suis internalization by DCs. This first study on receptors involved in DC activation by S. suis suggests a major involvement of MyD88 signaling pathways, mainly (but not exclusively through TLR2. A multimodal recognition involving a combination of different receptors seems essential for DC effective response to S. suis.

  2. Integrating TRPV1 Receptor Function with Capsaicin Psychophysics

    Directory of Open Access Journals (Sweden)

    Gregory Smutzer

    2016-01-01

    Full Text Available Capsaicin is a naturally occurring vanilloid that causes a hot, pungent sensation in the human oral cavity. This trigeminal stimulus activates TRPV1 receptors and stimulates an influx of cations into sensory cells. TRPV1 receptors function as homotetramers that also respond to heat, proinflammatory substances, lipoxygenase products, resiniferatoxin, endocannabinoids, protons, and peptide toxins. Kinase-mediated phosphorylation of TRPV1 leads to increased sensitivity to both chemical and thermal stimuli. In contrast, desensitization occurs via a calcium-dependent mechanism that results in receptor dephosphorylation. Human psychophysical studies have shown that capsaicin is detected at nanomole amounts and causes desensitization in the oral cavity. Psychophysical studies further indicate that desensitization can be temporarily reversed in the oral cavity if stimulation with capsaicin is resumed at short interstimulus intervals. Pretreatment of lingual epithelium with capsaicin modulates the perception of several primary taste qualities. Also, sweet taste stimuli may decrease the intensity of capsaicin perception in the oral cavity. In addition, capsaicin perception and hedonic responses may be modified by diet. Psychophysical studies with capsaicin are consistent with recent findings that have identified TRPV1 channel modulation by phosphorylation and interactions with membrane inositol phospholipids. Future studies will further clarify the importance of capsaicin and its receptor in human health and nutrition.

  3. Odin (ANKS1A modulates EGF receptor recycling and stability.

    Directory of Open Access Journals (Sweden)

    Jiefei Tong

    Full Text Available The ANKS1A gene product, also known as Odin, was first identified as a tyrosine-phosphorylated component of the epidermal growth factor receptor network. Here we show that Odin functions as an effector of EGFR recycling. In EGF-stimulated HEK293 cells tyrosine phosphorylation of Odin was induced prior to EGFR internalization and independent of EGFR-to-ERK signaling. Over-expression of Odin increased EGF-induced EGFR trafficking to recycling endosomes and recycling back to the cell surface, and decreased trafficking to lysosomes and degradation. Conversely, Odin knockdown in both HEK293 and the non-small cell lung carcinoma line RVH6849, which expresses roughly 10-fold more EGF receptors than HEK293, caused decreased EGFR recycling and accelerated trafficking to the lysosome and degradation. By governing the endocytic fate of internalized receptors, Odin may provide a layer of regulation that enables cells to contend with receptor cell densities and ligand concentration gradients that are physiologically and pathologically highly variable.

  4. Urolinin: The First Linear Peptidic Urotensin-II Receptor Agonist.

    Science.gov (United States)

    Bandholtz, Sebastian; Erdmann, Sarah; von Hacht, Jan Lennart; Exner, Samantha; Krause, Gerd; Kleinau, Gunnar; Grötzinger, Carsten

    2016-11-23

    This study investigated the role of individual U-II amino acid positions and side chain characteristics important for U-IIR activation. A complete permutation library of 209 U-II variants was studied in an activity screen that contained single substitution variants of each position with one of the other 19 proteinogenic amino acids. Receptor activation was measured using a cell-based high-throughput fluorescence calcium mobilization assay. We generated the first complete U-II substitution map for U-II receptor activation, resulting in a detailed view into the structural features required for receptor activation, accompanied by complementary information from receptor modeling and ligand docking studies. On the basis of the systematic SAR study of U-II, we created 33 further short and linear U-II variants from eight to three amino acids in length, including d- and other non-natural amino acids. We identified the first high-potency linear U-II analogues. Urolinin, a linear U-II agonist (nWWK-Tyr(3-NO 2 )-Abu), shows low nanomolar potency as well as improved metabolic stability.

  5. Oxytocin and Estrogen Receptor β in the Brain: An Overview

    Directory of Open Access Journals (Sweden)

    Alexandra eAcevedo-Rodriguez

    2015-10-01

    Full Text Available Oxytocin is a neuropeptide synthesized primarily by neurons of the paraventricular and supraoptic nuclei of the hypothalamus. These neurons have axons that project into the posterior pituitary and release oxytocin into the bloodstream to promote labor and lactation; however, oxytocin neurons also project to other brain areas where it plays a role in numerous brain functions. Oxytocin binds to the widely expressed oxytocin receptor, and, in doing so, it regulates homeostatic processes, social recognition and fear conditioning. In addition to these functions, oxytocin decreases neuroendocrine stress signaling and anxiety-related and depression-like behaviors. Steroid hormones differentially modulate stress responses and alter oxytocin receptor expression. In particular, estrogen receptor β activation has been found to both reduce anxiety-related behaviors and increase oxytocin peptide transcription, suggesting a role for oxytocin in this estrogen receptor β mediated anxiolytic effect. Further research is needed to identify modulators of oxytocin signaling and the pathways utilized and to elucidate molecular mechanisms controlling oxytocin expression to allow better therapeutic manipulations of this system in patient populations.

  6. Interaction between retinoid acid receptor-related orphan receptor alpha (RORA and neuropeptide S receptor 1 (NPSR1 in asthma.

    Directory of Open Access Journals (Sweden)

    Nathalie Acevedo

    Full Text Available Retinoid acid receptor-related Orphan Receptor Alpha (RORA was recently identified as a susceptibility gene for asthma in a genome-wide association study. To investigate the impact of RORA on asthma susceptibility, we performed a genetic association study between RORA single nucleotide polymorphisms (SNPs in the vicinity of the asthma-associated SNP (rs11071559 and asthma-related traits. Because the regulatory region of a previously implicated asthma susceptibility gene, Neuropeptide S receptor 1 (NPSR1, has predicted elements for RORA binding, we hypothesized that RORA may interact biologically and genetically with NPSR1. 37 RORA SNPs and eight NPSR1 SNPs were genotyped in the Swedish birth cohort BAMSE (2033 children and the European cross-sectional PARSIFAL study (1120 children. Seven RORA SNPs confined into a 49 kb region were significantly associated with physician-diagnosed childhood asthma. The most significant association with rs7164773 (T/C was driven by the CC genotype in asthma cases (OR = 2.0, 95%CI 1.36-2.93, p = 0.0003 in BAMSE; and 1.61, 1.18-2.19, p = 0.002 in the combined BAMSE-PARSIFAL datasets, respectively, and strikingly, the risk effect was dependent on the Gln344Arg mutation in NPSR1. In cell models, stimulation of NPSR1 activated a pathway including RORA and other circadian clock genes. Over-expression of RORA decreased NPSR1 promoter activity further suggesting a regulatory loop between these genes. In addition, Rora mRNA expression was lower in the lung tissue of Npsr1 deficient mice compared to wildtype littermates during the early hours of the light period. We conclude that RORA SNPs are associated with childhood asthma and show epistasis with NPSR1, and the interaction between RORA and NPSR1 may be of biological relevance. Combinations of common susceptibility alleles and less common functional polymorphisms may modify the joint risk effects on asthma susceptibility.

  7. Characterization of Odorant Receptors from a Non-ditrysian Moth, Eriocrania semipurpurella Sheds Light on the Origin of Sex Pheromone Receptors in Lepidoptera.

    Science.gov (United States)

    Yuvaraj, Jothi Kumar; Corcoran, Jacob A; Andersson, Martin N; Newcomb, Richard D; Anderbrant, Olle; Löfstedt, Christer

    2017-11-01

    Pheromone receptors (PRs) are essential in moths to detect sex pheromones for mate finding. However, it remains unknown from which ancestral proteins these specialized receptors arose. The oldest lineages of moths, so-called non-ditrysian moths, use short-chain pheromone components, secondary alcohols, or ketones, so called Type 0 pheromones that are similar to many common plant volatiles. It is, therefore, possible that receptors for these ancestral pheromones evolved from receptors detecting plant volatiles. Hence, we identified the odorant receptors (ORs) from a non-ditrysian moth, Eriocrania semipurpurella (Eriocraniidae, Lepidoptera), and performed functional characterization of ORs using HEK293 cells. We report the first receptors that respond to Type 0 pheromone compounds; EsemOR3 displayed highest sensitivity toward (2S, 6Z)-6-nonen-2-ol, whereas EsemOR5 was most sensitive to the behavioral antagonist (Z)-6-nonen-2-one. These receptors also respond to plant volatiles of similar chemical structures, but with lower sensitivity. Phylogenetically, EsemOR3 and EsemOR5 group with a plant volatile-responding receptor from the tortricid moth Epiphyas postvittana (EposOR3), which together reside outside the previously defined lepidopteran PR clade that contains the PRs from more derived lepidopteran families. In addition, one receptor (EsemOR1) that falls at the base of the lepidopteran PR clade, responded specifically to β-caryophyllene and not to any other additional plant or pheromone compounds. Our results suggest that PRs for Type 0 pheromones have evolved from ORs that detect structurally-related plant volatiles. They are unrelated to PRs detecting pheromones in more derived Lepidoptera, which, in turn, also independently may have evolved a novel function from ORs detecting plant volatiles. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  8. International Union of Pharmacology. LXXXIX. Update on the Extended Family of Chemokine Receptors and Introducing a New Nomenclature for Atypical Chemokine Receptors

    Science.gov (United States)

    Bachelerie, Francoise; Ben-Baruch, Adit; Burkhardt, Amanda M.; Combadiere, Christophe; Farber, Joshua M.; Graham, Gerard J.; Horuk, Richard; Sparre-Ulrich, Alexander Hovard; Locati, Massimo; Luster, Andrew D.; Mantovani, Alberto; Matsushima, Kouji; Nibbs, Robert; Nomiyama, Hisayuki; Power, Christine A.; Proudfoot, Amanda E. I.; Rosenkilde, Mette M.; Rot, Antal; Sozzani, Silvano; Thelen, Marcus; Yoshie, Osamu; Zlotnik, Albert

    2014-01-01

    Sixteen years ago, the Nomenclature Committee of the International Union of Pharmacology approved a system for naming human seven-transmembrane (7TM) G protein-coupled chemokine receptors, the large family of leukocyte chemoattractant receptors that regulates immune system development and function, in large part by mediating leukocyte trafficking. This was announced in Pharmacological Reviews in a major overview of the first decade of research in this field [Murphy PM, Baggiolini M, Charo IF, Hébert CA, Horuk R, Matsushima K, Miller LH, Oppenheim JJ, and Power CA (2000) Pharmacol Rev 52:145–176]. Since then, several new receptors have been discovered, and major advances have been made for the others in many areas, including structural biology, signal transduction mechanisms, biology, and pharmacology. New and diverse roles have been identified in infection, immunity, inflammation, development, cancer, and other areas. The first two drugs acting at chemokine receptors have been approved by the U.S. Food and Drug Administration (FDA), maraviroc targeting CCR5 in human immunodeficiency virus (HIV)/AIDS, and plerixafor targeting CXCR4 for stem cell mobilization for transplantation in cancer, and other candidates are now undergoing pivotal clinical trials for diverse disease indications. In addition, a subfamily of atypical chemokine receptors has emerged that may signal through arrestins instead of G proteins to act as chemokine scavengers, and many microbial and invertebrate G protein-coupled chemokine receptors and soluble chemokine-binding proteins have been described. Here, we review this extended family of chemokine receptors and chemokine-binding proteins at the basic, translational, and clinical levels, including an update on drug development. We also introduce a new nomenclature for atypical chemokine receptors with the stem ACKR (atypical chemokine receptor) approved by the Nomenclature Committee of the International Union of Pharmacology and the Human

  9. High throughput mutagenesis for identification of residues regulating human prostacyclin (hIP receptor expression and function.

    Directory of Open Access Journals (Sweden)

    Anke Bill

    Full Text Available The human prostacyclin receptor (hIP receptor is a seven-transmembrane G protein-coupled receptor (GPCR that plays a critical role in vascular smooth muscle relaxation and platelet aggregation. hIP receptor dysfunction has been implicated in numerous cardiovascular abnormalities, including myocardial infarction, hypertension, thrombosis and atherosclerosis. Genomic sequencing has discovered several genetic variations in the PTGIR gene coding for hIP receptor, however, its structure-function relationship has not been sufficiently explored. Here we set out to investigate the applicability of high throughput random mutagenesis to study the structure-function relationship of hIP receptor. While chemical mutagenesis was not suitable to generate a mutagenesis library with sufficient coverage, our data demonstrate error-prone PCR (epPCR mediated mutagenesis as a valuable method for the unbiased screening of residues regulating hIP receptor function and expression. Here we describe the generation and functional characterization of an epPCR derived mutagenesis library compromising >4000 mutants of the hIP receptor. We introduce next generation sequencing as a useful tool to validate the quality of mutagenesis libraries by providing information about the coverage, mutation rate and mutational bias. We identified 18 mutants of the hIP receptor that were expressed at the cell surface, but demonstrated impaired receptor function. A total of 38 non-synonymous mutations were identified within the coding region of the hIP receptor, mapping to 36 distinct residues, including several mutations previously reported to affect the signaling of the hIP receptor. Thus, our data demonstrates epPCR mediated random mutagenesis as a valuable and practical method to study the structure-function relationship of GPCRs.

  10. High throughput mutagenesis for identification of residues regulating human prostacyclin (hIP) receptor expression and function.

    Science.gov (United States)

    Bill, Anke; Rosethorne, Elizabeth M; Kent, Toby C; Fawcett, Lindsay; Burchell, Lynn; van Diepen, Michiel T; Marelli, Anthony; Batalov, Sergey; Miraglia, Loren; Orth, Anthony P; Renaud, Nicole A; Charlton, Steven J; Gosling, Martin; Gaither, L Alex; Groot-Kormelink, Paul J

    2014-01-01

    The human prostacyclin receptor (hIP receptor) is a seven-transmembrane G protein-coupled receptor (GPCR) that plays a critical role in vascular smooth muscle relaxation and platelet aggregation. hIP receptor dysfunction has been implicated in numerous cardiovascular abnormalities, including myocardial infarction, hypertension, thrombosis and atherosclerosis. Genomic sequencing has discovered several genetic variations in the PTGIR gene coding for hIP receptor, however, its structure-function relationship has not been sufficiently explored. Here we set out to investigate the applicability of high throughput random mutagenesis to study the structure-function relationship of hIP receptor. While chemical mutagenesis was not suitable to generate a mutagenesis library with sufficient coverage, our data demonstrate error-prone PCR (epPCR) mediated mutagenesis as a valuable method for the unbiased screening of residues regulating hIP receptor function and expression. Here we describe the generation and functional characterization of an epPCR derived mutagenesis library compromising >4000 mutants of the hIP receptor. We introduce next generation sequencing as a useful tool to validate the quality of mutagenesis libraries by providing information about the coverage, mutation rate and mutational bias. We identified 18 mutants of the hIP receptor that were expressed at the cell surface, but demonstrated impaired receptor function. A total of 38 non-synonymous mutations were identified within the coding region of the hIP receptor, mapping to 36 distinct residues, including several mutations previously reported to affect the signaling of the hIP receptor. Thus, our data demonstrates epPCR mediated random mutagenesis as a valuable and practical method to study the structure-function relationship of GPCRs.

  11. Human genetics as a tool to identify progranulin regulators.

    Science.gov (United States)

    Nicholson, Alexandra M; Finch, NiCole A; Rademakers, Rosa

    2011-11-01

    Frontotemporal lobar degeneration (FTLD) is a common neurodegenerative disorder that predominantly affects individuals under the age of 65. It is known that the most common pathological subtype is FTLD with TAR DNA-binding protein 43 inclusions (FTLD-TDP). FTLD has a strong genetic component with about 50% of cases having a positive family history. Mutations identified in the progranulin gene (GRN) have been shown to cause FTLD-TDP as a result of progranulin haploinsufficiency. These findings suggest a progranulin-dependent mechanism in this pathological FTLD subtype. Thus, identifying regulators of progranulin levels is essential for new therapies and treatments for FTLD and related disorders. In this review, we discuss the role of genetic studies in identifying progranulin regulators, beginning with the discovery of pathogenic GRN mutations and additional GRN risk variants. We also cover more recent genetic advances, including the detection of variants in the transmembrane protein 106 B gene that increase FTLD-TDP risk presumably by modulating progranulin levels and the identification of a potential progranulin receptor, sortilin. This review highlights the importance of genetic studies in the context of FTLD and further emphasizes the need for future genetic and cell biology research to continue the effort in finding a cure for progranulin-related diseases.

  12. Triclocarban mediates induction of xenobiotic metabolism through activation of the constitutive androstane receptor and the estrogen receptor alpha.

    Directory of Open Access Journals (Sweden)

    Mei-Fei Yueh

    Full Text Available Triclocarban (3,4,4'-trichlorocarbanilide, TCC is used as a broad-based antimicrobial agent that is commonly added to personal hygiene products. Because of its extensive use in the health care industry and resistance to degradation in sewage treatment processes, TCC has become a significant waste product that is found in numerous environmental compartments where humans and wildlife can be exposed. While TCC has been linked to a range of health and environmental effects, few studies have been conducted linking exposure to TCC and induction of xenobiotic metabolism through regulation by environmental sensors such as the nuclear xenobiotic receptors (XenoRs. To identify the ability of TCC to activate xenobiotic sensors, we monitored XenoR activities in response to TCC treatment using luciferase-based reporter assays. Among the XenoRs in the reporter screening assay, TCC promotes both constitutive androstane receptor (CAR and estrogen receptor alpha (ERα activities. TCC treatment to hUGT1 mice resulted in induction of the UGT1A genes in liver. This induction was dependent upon the constitutive active/androstane receptor (CAR because no induction occurred in hUGT1Car(-/- mice. Induction of the UGT1A genes by TCC corresponded with induction of Cyp2b10, another CAR target gene. TCC was demonstrated to be a phenobarbital-like activator of CAR in receptor-based assays. While it has been suggested that TCC be classified as an endocrine disruptor, it activates ERα leading to induction of Cyp1b1 in female ovaries as well as in promoter activity. Activation of ERα by TCC in receptor-based assays also promotes induction of human CYP2B6. These observations demonstrate that TCC activates nuclear xenobiotic receptors CAR and ERα both in vivo and in vitro and might have the potential to alter normal physiological homeostasis. Activation of these xenobiotic-sensing receptors amplifies gene expression profiles that might represent a mechanistic base for

  13. Dm5-HT2B: Pharmacological Characterization of the Fifth Serotonin Receptor Subtype of Drosophila melanogaster.

    Science.gov (United States)

    Blenau, Wolfgang; Daniel, Stöppler; Balfanz, Sabine; Thamm, Markus; Baumann, Arnd

    2017-01-01

    Serotonin (5-hydroxytryptamine, 5-HT) is an important regulator of physiological and behavioral processes in both protostomes (e.g., insects) and deuterostomes (e.g., mammals). In insects, serotonin has been found to modulate the heart rate and to control secretory processes, development, circadian rhythms, aggressive behavior, as well as to contribute to learning and memory. Serotonin exerts its activity by binding to and activating specific membrane receptors. The clear majority of these receptors belong to the superfamily of G-protein-coupled receptors. In Drosophila melanogaster , a total of five genes have been identified coding for 5-HT receptors. From this family of proteins, four have been pharmacologically examined in greater detail, so far. While Dm5-HT 1A , Dm5-HT 1B , and Dm5-HT 7 couple to cAMP signaling cascades, the Dm5-HT 2A receptor leads to Ca 2+ signaling in an inositol-1,4,5-trisphosphate-dependent manner. Based on sequence similarity to homologous genes in other insects, a fifth D. melanogaster gene was uncovered coding for a Dm5-HT 2B receptor. Knowledge about this receptor's pharmacological properties is very limited. This is quite surprising because Dm5-HT 2B has been attributed to distinct physiological functions based on genetic interference with its gene expression. Mutations were described reducing the response of the larval heart to 5-HT, and specific knockdown of Dm5-HT 2B mRNA in hemocytes resulted in a higher susceptibility of the flies to bacterial infection. To gain deeper understanding of Dm5-HT 2B 's pharmacology, we evaluated the receptor's response to a series of established 5-HT receptor agonists and antagonists in a functional cell-based assay. Metoclopramide and mianserin were identified as two potent antagonists that may allow pharmacological interference with Dm5-HT 2B signaling in vitro and in vivo .

  14. Cell-Type-Specific Regulation of the Retinoic Acid Receptor Mediated by the Orphan Nuclear Receptor TLX†

    Science.gov (United States)

    Kobayashi, Mime; Yu, Ruth T.; Yasuda, Kunio; Umesono, Kazuhiko

    2000-01-01

    Malformations in the eye can be caused by either an excess or deficiency of retinoids. An early target gene of the retinoid metabolite, retinoic acid (RA), is that encoding one of its own receptors, the retinoic acid receptor β (RARβ). To better understand the mechanisms underlying this autologous regulation, we characterized the chick RARβ2 promoter. The region surrounding the transcription start site of the avian RARβ2 promoter is over 90% conserved with the corresponding region in mammals and confers strong RA-dependent transactivation in primary cultured embryonic retina cells. This response is selective for RAR but not retinoid X receptor-specific agonists, demonstrating a principal role for RAR(s) in retina cells. Retina cells exhibit a far higher sensitivity to RA than do fibroblasts or osteoblasts, a property we found likely due to expression of the orphan nuclear receptor TLX. Ectopic expression of TLX in fibroblasts resulted in increased sensitivity to RA induction, an effect that is conserved between chick and mammals. We have identified a cis element, the silencing element relieved by TLX (SET), within the RARβ2 promoter region which confers TLX- and RA-dependent transactivation. These results indicate an important role for TLX in autologous regulation of the RARβ gene in the eye. PMID:11073974

  15. Cell-type-specific regulation of the retinoic acid receptor mediated by the orphan nuclear receptor TLX.

    Science.gov (United States)

    Kobayashi, M; Yu, R T; Yasuda, K; Umesono, K

    2000-12-01

    Malformations in the eye can be caused by either an excess or deficiency of retinoids. An early target gene of the retinoid metabolite, retinoic acid (RA), is that encoding one of its own receptors, the retinoic acid receptor beta (RARbeta). To better understand the mechanisms underlying this autologous regulation, we characterized the chick RARbeta2 promoter. The region surrounding the transcription start site of the avian RARbeta2 promoter is over 90% conserved with the corresponding region in mammals and confers strong RA-dependent transactivation in primary cultured embryonic retina cells. This response is selective for RAR but not retinoid X receptor-specific agonists, demonstrating a principal role for RAR(s) in retina cells. Retina cells exhibit a far higher sensitivity to RA than do fibroblasts or osteoblasts, a property we found likely due to expression of the orphan nuclear receptor TLX. Ectopic expression of TLX in fibroblasts resulted in increased sensitivity to RA induction, an effect that is conserved between chick and mammals. We have identified a cis element, the silencing element relieved by TLX (SET), within the RARbeta2 promoter region which confers TLX- and RA-dependent transactivation. These results indicate an important role for TLX in autologous regulation of the RARbeta gene in the eye.

  16. Alternative activation of macrophages and pulmonary fibrosis are modulated by scavenger receptor, macrophage receptor with collagenous structure.

    Science.gov (United States)

    Murthy, Shubha; Larson-Casey, Jennifer L; Ryan, Alan J; He, Chao; Kobzik, Lester; Carter, A Brent

    2015-08-01

    Alternative activation of alveolar macrophages is linked to fibrosis following exposure to asbestos. The scavenger receptor, macrophage receptor with collagenous structure (MARCO), provides innate immune defense against inhaled particles and pathogens; however, a receptor for asbestos has not been identified. We hypothesized that MARCO acts as an initial signaling receptor for asbestos, polarizes macrophages to a profibrotic M2 phenotype, and is required for the development of asbestos-induced fibrosis. Compared with normal subjects, alveolar macrophages isolated from patients with asbestosis express higher amounts of MARCO and have greater profibrotic polarization. Arginase 1 (40-fold) and IL-10 (265-fold) were higher in patients. In vivo, the genetic deletion of MARCO attenuated the profibrotic environment and pulmonary fibrosis in mice exposed to chrysotile. Moreover, alveolar macrophages from MARCO(-/-) mice polarize to an M1 phenotype, whereas wild-type mice have higher Ym1 (>3.0-fold) and nearly 7-fold more active TGF-β1 in bronchoalveolar lavage (BAL) fluid (BALF). Arg(432) and Arg(434) in domain V of MARCO are required for the polarization of macrophages to a profibrotic phenotype as mutation of these residues reduced FIZZ1 expression (17-fold) compared with cells expressing MARCO. These observations demonstrate that a macrophage membrane protein regulates the fibrotic response to lung injury and suggest a novel target for therapeutic intervention. © FASEB.

  17. PAF receptor structure: a hypothesis.

    Science.gov (United States)

    Godfroid, J J; Dive, G; Lamotte-Brasseur, J; Batt, J P; Heymans, F

    1991-12-01

    Different hypotheses of the structure of platelet-activating factor (PAF) receptor based on structure-activity relationships of agonists and antagonists are reviewed. For an agonistic effect, strong hydrophobic interactions and an ether function are required in position-1 of the glycerol backbone; chain length limitations and steric hindrance demand a small group in position-2. The unusual structural properties of non-PAF-like antagonists required 3-D electrostatic potential calculations. This method applied to seven potent antagonists suggests a strong "Cache-orielles" (ear-muff) effect, i.e., two strong electronegative wells (isocontour at -10 Kcal/mole) are located at 180 degrees to each other and at a relatively constant distance. Initial consideration of the "Cache-oreilles" effect implied the structure of a bipolarized cylinder of 10-12 A diameter for the receptor. However, very recent results on studies with agonists and antagonists structurally similar to PAF suggest that the receptor may in fact be a multi-polarized cylinder.

  18. β adrenergic receptor modulation of neurotransmission to cardiac vagal neurons in the nucleus ambiguus.

    Science.gov (United States)

    Bateman, R J; Boychuk, C R; Philbin, K E; Mendelowitz, D

    2012-05-17

    β-adrenergic receptors are a class of G protein-coupled receptors that have essential roles in regulating heart rate, blood pressure, and other cardiorespiratory functions. Although the role of β adrenergic receptors in the peripheral nervous system is well characterized, very little is known about their role in the central nervous system despite being localized in many brain regions involved in autonomic activity and regulation. Since parasympathetic activity to the heart is dominated by cardiac vagal neurons (CVNs) originating in the nucleus ambiguus (NA), β adrenergic receptors localized in the NA represent a potential target for modulating cardiac vagal activity and heart rate. This study tests the hypothesis that activation of β adrenergic receptors alters the membrane properties and synaptic neurotransmission to CVNs. CVNs were identified in brainstem slices, and membrane properties and synaptic events were recorded using the whole-cell voltage-clamp technique. The nonselective β agonist isoproterenol significantly decreased inhibitory GABAergic and glycinergic as well as excitatory glutamatergic neurotransmission to CVNs. In addition, the β(1)-selective receptor agonist dobutamine, but not β(2) or β(3) receptor agonists, significantly decreased inhibitory GABAergic and glycinergic and excitatory glutamatergic neurotransmission to CVNs. These decreases in neurotransmission to CVNs persisted in the presence of tetrodotoxin (TTX). These results provide a mechanism by which activation of adrenergic receptors in the brainstem can alter parasympathetic activity to the heart. Likely physiological roles for this adrenergic receptor activation are coordination of parasympathetic-sympathetic activity and β receptor-mediated increases in heart rate upon arousal. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. [Serum leptin levels and soluble leptin