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  1. Article: Allosteric functioning of dimeric class C G-protein-coupled receptors.

    Pin, J-P / Kniazeff, J / Liu, J / Binet, V / Goudet, C / Rondard, P / Prézeau, L

    The FEBS journal

    2005  Volume 272, Issue 12, Page(s) 2947–2955

    Abstract: Whereas most membrane receptors are oligomeric entities, G-protein-coupled receptors have long been thought to function as monomers. Within the last 15 years, accumulating data have indicated that G-protein-coupled receptors can form dimers or even ... ...

    Abstract Whereas most membrane receptors are oligomeric entities, G-protein-coupled receptors have long been thought to function as monomers. Within the last 15 years, accumulating data have indicated that G-protein-coupled receptors can form dimers or even higher ordered oligomers, but the general functional significance of this phenomena is not yet clear. Among the large G-protein-coupled receptor family, class C receptors represent a well-recognized example of constitutive dimers, both subunits being linked, in most cases, by a disulfide bridge. In this review article, we show that class C G-protein-coupled receptors are multidomain proteins and highlight the importance of their dimerization for activation. We illustrate several consequences of this in terms of specific functional properties and drug development.
    MeSH term(s) Animals ; Dimerization ; Humans ; Models, Molecular ; Protein Conformation ; Protein Structure, Tertiary ; Receptors, G-Protein-Coupled/chemistry ; Receptors, G-Protein-Coupled/metabolism
    Chemical Substances Receptors, G-Protein-Coupled
    Language English
    Publishing date 2005-06
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 2173655-8
    ISSN 1742-4658 ; 1742-464X
    ISSN (online) 1742-4658
    ISSN 1742-464X
    DOI 10.1111/j.1742-4658.2005.04728.x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Molecular mechanisms of GABA(B) receptor activation: new insights from the mechanism of action of CGP7930, a positive allosteric modulator.

    Binet, V / Goudet, C / Brajon, C / Le Corre, L / Acher, F / Pin, J-P / Prézeau, L

    Biochemical Society transactions

    2004  Volume 32, Issue Pt 5, Page(s) 871–872

    Abstract: The GABA(B) (gamma-aminobutyric acid-B) receptor is composed of two subunits, GABA(B1) and GABA(B2). Both subunits share structural homology with other class-III G-protein-coupled receptors. They contain two main domains, a heptahelical domain typical of ...

    Abstract The GABA(B) (gamma-aminobutyric acid-B) receptor is composed of two subunits, GABA(B1) and GABA(B2). Both subunits share structural homology with other class-III G-protein-coupled receptors. They contain two main domains, a heptahelical domain typical of all G-protein-coupled receptors and a large ECD (extracellular domain). It has not been demonstrated whether the association of these two subunits is always required for function. However, GABA(B2) plays a major role in coupling with G-proteins, and GABA(B1) has been shown to bind GABA. To date, only ligands interacting with GABA(B1)-ECD have been identified. In the present study, we explored the mechanism of action of CGP7930, a compound described as a positive allosteric regulator of the GABA(B) receptor. We have shown that it can weakly activate the wild-type GABA(B) receptor, but also the GABA(B2) expressed alone, thus being the first described agonist of GABA(B2). CGP7930 retains its weak agonist activity on a GABA(B2) subunit deleted of its ECD. Thus the heptahelical domain of GABA(B2) behaves similar to a rhodopsin-like receptor. These results open new strategies for studying the mechanism of activation of GABA(B) receptor and examine any possible role of GABA(B2).
    MeSH term(s) Allosteric Site ; Binding Sites ; Cell Line ; Humans ; Models, Biological ; Models, Molecular ; Phenols/chemistry ; Protein Binding ; Protein Structure, Tertiary ; Receptors, GABA-B/metabolism
    Chemical Substances 2,6-di-tert-butyl-4-(3-hydroxy-2,2-dimethylpropyl)phenol ; Phenols ; Receptors, GABA-B
    Language English
    Publishing date 2004-11
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 184237-7
    ISSN 1470-8752 ; 0300-5127
    ISSN (online) 1470-8752
    ISSN 0300-5127
    DOI 10.1042/BST0320871
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Common Structural Requirements for Heptahelical Domain Function in Class A and Class C G Protein-coupled Receptors

    Binet, Virginie / Duthey, Béatrice / Lecaillon, Jennifer / Vol, Claire / Quoyer, Julie / Labesse, Gilles / Pin, Jean-Philippe / Prézeau, Laurent

    Journal of biological chemistry. 2007 Apr. 20, v. 282, no. 16

    2007  

    Abstract: G protein-coupled receptors (GPCRs) are key players in cell communication. Several classes of such receptors have been identified. Although all GPCRs possess a heptahelical domain directly activating G proteins, important structural and sequence ... ...

    Abstract G protein-coupled receptors (GPCRs) are key players in cell communication. Several classes of such receptors have been identified. Although all GPCRs possess a heptahelical domain directly activating G proteins, important structural and sequence differences within receptors from different classes suggested distinct activation mechanisms. Here we show that highly conserved charged residues likely involved in an interaction network between transmembrane domains (TM) 3 and 6 at the cytoplasmic side of class C GPCRs are critical for activation of the γ-aminobutyric acid type B receptor. Indeed, the loss of function resulting from the mutation of the conserved lysine residue into aspartate or glutamate in the TM3 of γ-aminobutyric acid type B₂ can be partly rescued by mutating the conserved acidic residue of TM6 into either lysine or arginine. In addition, mutation of the conserved lysine into an acidic residue leads to a nonfunctional receptor that displays a high agonist affinity. This is reminiscent of a similar ionic network that constitutes a lock stabilizing the inactive state of many class A rhodopsin-like GPCRs. These data reveal that despite their original structure, class C GPCRs share with class A receptors at least some common structural feature controlling G protein activation.
    Language English
    Dates of publication 2007-0420
    Size p. 12154-12163.
    Publishing place American Society for Biochemistry and Molecular Biology
    Document type Article
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: The heptahelical domain of GABA(B2) is activated directly by CGP7930, a positive allosteric modulator of the GABA(B) receptor.

    Binet, Virginie / Brajon, Carole / Le Corre, Laurent / Acher, Francine / Pin, Jean-Philippe / Prézeau, Laurent

    The Journal of biological chemistry

    2004  Volume 279, Issue 28, Page(s) 29085–29091

    Abstract: The gamma-aminobutyric acid, type B (GABA(B)) receptor is well recognized as being composed of two subunits, GABA(B1) and GABA(B2). Both subunits share structural homology with other class-III G-protein-coupled receptors. They are composed of two main ... ...

    Abstract The gamma-aminobutyric acid, type B (GABA(B)) receptor is well recognized as being composed of two subunits, GABA(B1) and GABA(B2). Both subunits share structural homology with other class-III G-protein-coupled receptors. They are composed of two main domains: a heptahelical domain (HD) typical of all G-protein-coupled receptors and a large extracellular domain (ECD). Although GABA(B1) binds GABA, GABA(B2) is required for GABA(B1) to reach the cell surface. However, it is still not demonstrated whether the association of these two subunits is always required for function in the brain. Indeed, GABA(B2) plays a major role in the coupling of the heteromer to G-proteins, such that it is possible that GABA(B2) can transmit a signal in the absence of GABA(B1). Today only ligands interacting with GABA(B1) ECD have been identified. Thus, the compounds acting exclusively on the GABA(B2) subunit will be helpful in analyzing the specific role of this subunit in the brain. Here, we explored the mechanism of action of CGP7930, a compound described as a positive allosteric regulator of the GABA(B) receptor. We showed that it activates the wild type GABA(B) receptor but with a low efficacy. The GABA(B2) HD is necessary for this effect, although one cannot exclude that CGP7930 could also bind to GABA(B1). Of interest, CGP7930 could activate GABA(B2) expressed alone and is the first described agonist of GABA(B2). Finally, we show that CGP7930 retains its agonist activity on a GABA(B2) subunit deleted of its ECD. This demonstrates that the HD of GABA(B2) behaves similar to a rhodopsin-like receptor, because it can reach the cell surface alone, can couple to G-protein, and be activated by agonists. These data open new strategies for studying the mechanism of activation of GABA(B) receptor and examine any possible role of homomeric GABA(B2) receptors.
    MeSH term(s) Allosteric Regulation ; Animals ; Cell Line ; Dimerization ; Dose-Response Relationship, Drug ; GABA-B Receptor Agonists ; GTP-Binding Proteins/metabolism ; Humans ; Inositol Phosphates/metabolism ; Ligands ; Mutagenesis, Site-Directed ; Phenols/metabolism ; Protein Structure, Tertiary ; Protein Subunits/agonists ; Protein Subunits/chemistry ; Protein Subunits/genetics ; Protein Subunits/metabolism ; Receptors, GABA-B/chemistry ; Receptors, GABA-B/genetics ; Receptors, GABA-B/metabolism ; gamma-Aminobutyric Acid/metabolism
    Chemical Substances 2,6-di-tert-butyl-4-(3-hydroxy-2,2-dimethylpropyl)phenol ; GABA-B Receptor Agonists ; Inositol Phosphates ; Ligands ; Phenols ; Protein Subunits ; Receptors, GABA-B ; gamma-Aminobutyric Acid (56-12-2) ; GTP-Binding Proteins (EC 3.6.1.-)
    Language English
    Publishing date 2004-05-04
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1074/jbc.M400930200
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Common structural requirements for heptahelical domain function in class A and class C G protein-coupled receptors.

    Binet, Virginie / Duthey, Béatrice / Lecaillon, Jennifer / Vol, Claire / Quoyer, Julie / Labesse, Gilles / Pin, Jean-Philippe / Prézeau, Laurent

    The Journal of biological chemistry

    2007  Volume 282, Issue 16, Page(s) 12154–12163

    Abstract: G protein-coupled receptors (GPCRs) are key players in cell communication. Several classes of such receptors have been identified. Although all GPCRs possess a heptahelical domain directly activating G proteins, important structural and sequence ... ...

    Abstract G protein-coupled receptors (GPCRs) are key players in cell communication. Several classes of such receptors have been identified. Although all GPCRs possess a heptahelical domain directly activating G proteins, important structural and sequence differences within receptors from different classes suggested distinct activation mechanisms. Here we show that highly conserved charged residues likely involved in an interaction network between transmembrane domains (TM) 3 and 6 at the cytoplasmic side of class C GPCRs are critical for activation of the gamma-aminobutyric acid type B receptor. Indeed, the loss of function resulting from the mutation of the conserved lysine residue into aspartate or glutamate in the TM3 of gamma-aminobutyric acid type B(2) can be partly rescued by mutating the conserved acidic residue of TM6 into either lysine or arginine. In addition, mutation of the conserved lysine into an acidic residue leads to a nonfunctional receptor that displays a high agonist affinity. This is reminiscent of a similar ionic network that constitutes a lock stabilizing the inactive state of many class A rhodopsin-like GPCRs. These data reveal that despite their original structure, class C GPCRs share with class A receptors at least some common structural feature controlling G protein activation.
    MeSH term(s) Amino Acid Motifs ; Amino Acid Sequence ; Arginine/chemistry ; Cell Line ; Cell Membrane/metabolism ; Cytoplasm/metabolism ; Humans ; Inositol Phosphates/chemistry ; Lysine/chemistry ; Models, Molecular ; Molecular Sequence Data ; Protein Structure, Tertiary ; Receptors, G-Protein-Coupled/chemistry ; Receptors, G-Protein-Coupled/physiology ; Receptors, GABA-B/metabolism ; Rhodopsin/chemistry
    Chemical Substances Inositol Phosphates ; Receptors, G-Protein-Coupled ; Receptors, GABA-B ; Rhodopsin (9009-81-8) ; Arginine (94ZLA3W45F) ; Lysine (K3Z4F929H6)
    Language English
    Publishing date 2007-02-19
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1074/jbc.M611071200
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Real-time analysis of agonist-induced activation of protease-activated receptor 1/Galphai1 protein complex measured by bioluminescence resonance energy transfer in living cells.

    Ayoub, Mohammed A / Maurel, Damien / Binet, Virginie / Fink, Michel / Prézeau, Laurent / Ansanay, Hervé / Pin, Jean-Philippe

    Molecular pharmacology

    2007  Volume 71, Issue 5, Page(s) 1329–1340

    Abstract: G protein-coupled receptors transmit extracellular signals into the cells by activating heterotrimeric G proteins, a process that is often followed by receptor desensitization. Monitoring such a process in real time and in living cells will help better ... ...

    Abstract G protein-coupled receptors transmit extracellular signals into the cells by activating heterotrimeric G proteins, a process that is often followed by receptor desensitization. Monitoring such a process in real time and in living cells will help better understand how G protein activation occurs. Energy transfer-based approaches [fluorescence resonance energy transfer (FRET) and bioluminescence resonance energy transfer (BRET)] were recently shown to be powerful methods to monitor the G protein-coupled receptors (GPCRs)-G protein association in living cells. Here, we used a BRET technique to monitor the coupling between the protease-activated receptor 1 (PAR1) and Galpha(i1) protein. A specific constitutive BRET signal can be measured between nonactivated PAR1 and the Galpha(i1) protein expressed at a physiological level. This signal is insensitive to pertussis toxin (PTX) and probably reflects the preassembly of these two proteins. The BRET signal rapidly increases upon receptor activation in a PTX-sensitive manner. The BRET signal then returns to the basal level after few minutes. The desensitization of the BRET signal is concomitant with beta-arrestin-1 recruitment to the receptor, consistent with the known rapid desensitization of PARs. The agonist-induced BRET increase was dependent on the insertion site of fluorophores in proteins. Taken together, our results show that BRET between GPCRs and Galpha proteins can be used to monitor the receptor activation in real time and in living cells. Our data also revealed that PAR1 can be part of a preassembled complex with Galpha(i1) protein, resulting either from a direct interaction between these partners or from their colocalization in specific microdomains, and that receptor activation probably results in rearrangements within such complexes.
    MeSH term(s) Amino Acid Sequence ; Animals ; Arrestins/metabolism ; COS Cells ; Cattle ; Cell Survival/drug effects ; Cercopithecus aethiops ; GTP-Binding Protein alpha Subunits, Gi-Go/agonists ; GTP-Binding Protein alpha Subunits, Gi-Go/metabolism ; Humans ; Kinetics ; Luminescent Proteins/metabolism ; Molecular Sequence Data ; Pertussis Toxin/pharmacology ; Protein Structure, Secondary/drug effects ; Protein Transport/drug effects ; Receptor, PAR-1/agonists ; Receptor, PAR-1/chemistry ; Receptor, PAR-1/metabolism ; Recombinant Fusion Proteins/metabolism ; Spectrometry, Fluorescence ; Thrombin/pharmacology ; beta-Arrestin 1 ; beta-Arrestins
    Chemical Substances ARRB1 protein, human ; Arrestins ; Luminescent Proteins ; Receptor, PAR-1 ; Recombinant Fusion Proteins ; beta-Arrestin 1 ; beta-Arrestins ; Pertussis Toxin (EC 2.4.2.31) ; Thrombin (EC 3.4.21.5) ; GTP-Binding Protein alpha Subunits, Gi-Go (EC 3.6.5.1)
    Language English
    Publishing date 2007-05
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 124034-1
    ISSN 1521-0111 ; 0026-895X
    ISSN (online) 1521-0111
    ISSN 0026-895X
    DOI 10.1124/mol.106.030304
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Demonstrating Agreement between Radio and Fluorescence Measurements of the Depth of Maximum of Extensive Air Showers at the Pierre Auger Observatory.

    Abdul Halim, A / Abreu, P / Aglietta, M / Allekotte, I / Cheminant, K Almeida / Almela, A / Aloisio, R / Alvarez-Muñiz, J / Yebra, J Ammerman / Anastasi, G A / Anchordoqui, L / Andrada, B / Andringa, S / Anukriti / Apollonio, L / Aramo, C / Ferreira, P R Araújo / Arnone, E / Velázquez, J C Arteaga /
    Assis, P / Avila, G / Avocone, E / Bakalova, A / Barbato, F / Mocellin, A Bartz / Bellido, J A / Berat, C / Bertaina, M E / Bhatta, G / Bianciotto, M / Biermann, P L / Binet, V / Bismark, K / Bister, T / Biteau, J / Blazek, J / Bleve, C / Blümer, J / Boháčová, M / Boncioli, D / Bonifazi, C / Arbeletche, L Bonneau / Borodai, N / Brack, J / Orchera, P G Brichetto / Briechle, F L / Bueno, A / Buitink, S / Buscemi, M / Büsken, M / Bwembya, A / Caballero-Mora, K S / Cabana-Freire, S / Caccianiga, L / Caruso, R / Castellina, A / Catalani, F / Cataldi, G / Cazon, L / Cerda, M / Cermenati, A / Chinellato, J A / Chudoba, J / Chytka, L / Clay, R W / Cerutti, A C Cobos / Colalillo, R / Coleman, A / Coluccia, M R / Conceição, R / Condorelli, A / Consolati, G / Conte, M / Convenga, F / Dos Santos, D Correia / Costa, P J / Covault, C E / Cristinziani, M / Sanchez, C S Cruz / Dasso, S / Daumiller, K / Dawson, B R / de Almeida, R M / de Jesús, J / de Jong, S J / Neto, J R T de Mello / De Mitri, I / de Oliveira, J / Franco, D de Oliveira / de Palma, F / de Souza, V / de Errico, B P de Souza / De Vito, E / Del Popolo, A / Deligny, O / Denner, N / Deval, L / di Matteo, A / Dobre, M / Dobrigkeit, C / D'Olivo, J C / Mendes, L M Domingues / Dorosti, Q / Dos Anjos, J C / Dos Anjos, R C / Ebr, J / Ellwanger, F / Emam, M / Engel, R / Epicoco, I / Erdmann, M / Etchegoyen, A / Evoli, C / Falcke, H / Farmer, J / Farrar, G / Fauth, A C / Fazzini, N / Feldbusch, F / Fenu, F / Fernandes, A / Fick, B / Figueira, J M / Filipčič, A / Fitoussi, T / Flaggs, B / Fodran, T / Fujii, T / Fuster, A / Galea, C / Galelli, C / García, B / Gaudu, C / Gemmeke, H / Gesualdi, F / Gherghel-Lascu, A / Ghia, P L / Giaccari, U / Glombitza, J / Gobbi, F / Gollan, F / Golup, G / Berisso, M Gómez / Vitale, P F Gómez / Gongora, J P / González, J M / González, N / Goos, I / Góra, D / Gorgi, A / Gottowik, M / Grubb, T D / Guarino, F / Guedes, G P / Guido, E / Gülzow, L / Hahn, S / Hamal, P / Hampel, M R / Hansen, P / Harari, D / Harvey, V M / Haungs, A / Hebbeker, T / Hojvat, C / Hörandel, J R / Horvath, P / Hrabovský, M / Huege, T / Insolia, A / Isar, P G / Janecek, P / Jilek, V / Johnsen, J A / Jurysek, J / Kampert, K-H / Keilhauer, B / Khakurdikar, A / Covilakam, V V Kizakke / Klages, H O / Kleifges, M / Knapp, F / Köhler, J / Kunka, N / Lago, B L / Langner, N / de Oliveira, M A Leigui / Lema-Capeans, Y / Letessier-Selvon, A / Lhenry-Yvon, I / Lopes, L / Lu, L / Luce, Q / Lundquist, J P / Payeras, A Machado / Majercakova, M / Mandat, D / Manning, B C / Mantsch, P / Marafico, S / Mariani, F M / Mariazzi, A G / Mariş, I C / Marsella, G / Martello, D / Martinelli, S / Bravo, O Martínez / Martins, M A / Mathes, H-J / Matthews, J / Matthiae, G / Mayotte, E / Mayotte, S / Mazur, P O / Medina-Tanco, G / Meinert, J / Melo, D / Menshikov, A / Merx, C / Michal, S / Micheletti, M I / Miramonti, L / Mollerach, S / Montanet, F / Morejon, L / Morello, C / Mulrey, K / Mussa, R / Namasaka, W M / Negi, S / Nellen, L / Nguyen, K / Nicora, G / Niechciol, M / Nitz, D / Nosek, D / Novotny, V / Nožka, L / Nucita, A / Núñez, L A / Oliveira, C / Palatka, M / Pallotta, J / Panja, S / Parente, G / Paulsen, T / Pawlowsky, J / Pech, M / Pękala, J / Pelayo, R / Pereira, L A S / Martins, E E Pereira / Armand, J Perez / Bertolli, C Pérez / Perrone, L / Petrera, S / Petrucci, C / Pierog, T / Pimenta, M / Platino, M / Pont, B / Pothast, M / Shahvar, M Pourmohammad / Privitera, P / Prouza, M / Puyleart, A / Querchfeld, S / Rautenberg, J / Ravignani, D / Akim, J V Reginatto / Reininghaus, M / Ridky, J / Riehn, F / Risse, M / Rizi, V / de Carvalho, W Rodrigues / Rodriguez, E / Rojo, J Rodriguez / Roncoroni, M J / Rossoni, S / Roth, M / Roulet, E / Rovero, A C / Ruehl, P / Saftoiu, A / Saharan, M / Salamida, F / Salazar, H / Salina, G / Gomez, J D Sanabria / Sánchez, F / Santos, E M / Santos, E / Sarazin, F / Sarmento, R / Sato, R / Savina, P / Schäfer, C M / Scherini, V / Schieler, H / Schimassek, M / Schimp, M / Schmidt, D / Scholten, O / Schoorlemmer, H / Schovánek, P / Schröder, F G / Schulte, J / Schulz, T / Sciutto, S J / Scornavacche, M / Segreto, A / Sehgal, S / Shivashankara, S U / Sigl, G / Silli, G / Sima, O / Simkova, K / Simon, F / Smau, R / Šmída, R / Sommers, P / Soriano, J F / Squartini, R / Stadelmaier, M / Stanič, S / Stasielak, J / Stassi, P / Strähnz, S / Straub, M / Suomijärvi, T / Supanitsky, A D / Svozilikova, Z / Szadkowski, Z / Tairli, F / Tapia, A / Taricco, C / Timmermans, C / Tkachenko, O / Tobiska, P / Peixoto, C J Todero / Tomé, B / Torrès, Z / Travaini, A / Travnicek, P / Trimarelli, C / Tueros, M / Unger, M / Vaclavek, L / Vacula, M / Galicia, J F Valdés / Valore, L / Varela, E / Vásquez-Ramírez, A / Veberič, D / Ventura, C / Quispe, I D Vergara / Verzi, V / Vicha, J / Vink, J / Vorobiov, S / Watanabe, C / Watson, A A / Weindl, A / Wiencke, L / Wilczyński, H / Wittkowski, D / Wundheiler, B / Yue, B / Yushkov, A / Zapparrata, O / Zas, E / Zavrtanik, D / Zavrtanik, M

    Physical review letters

    2024  Volume 132, Issue 2, Page(s) 21001

    Abstract: We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre ...

    Abstract We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.
    Language English
    Publishing date 2024-01-26
    Publishing country United States
    Document type Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.132.021001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Oct-1 potentiates CREB-driven cyclin D1 promoter activation via a phospho-CREB- and CREB binding protein-independent mechanism.

    Boulon, Séverine / Dantonel, Jean-Christophe / Binet, Virginie / Vié, Annick / Blanchard, Jean-Marie / Hipskind, Robert A / Philips, Alexandre

    Molecular and cellular biology

    2001  Volume 22, Issue 22, Page(s) 7769–7779

    Abstract: Cyclin D1, the regulatory subunit for mid-G(1) cyclin-dependent kinases, controls the expression of numerous cell cycle genes. A cyclic AMP-responsive element (CRE), located upstream of the cyclin D1 mRNA start site, integrates mitogenic signals that ... ...

    Abstract Cyclin D1, the regulatory subunit for mid-G(1) cyclin-dependent kinases, controls the expression of numerous cell cycle genes. A cyclic AMP-responsive element (CRE), located upstream of the cyclin D1 mRNA start site, integrates mitogenic signals that target the CRE-binding factor CREB, which can recruit the transcriptional coactivator CREB-binding protein (CBP). We describe an alternative mechanism for CREB-driven cyclin D1 induction that involves the ubiquitous POU domain protein Oct-1. In the breast cancer cell line MCF-7, overexpression of Oct-1 or its POU domain strongly increases transcriptional activation of cyclin D1 and GAL4 reporter genes that is specifically dependent upon CREB but independent of Oct-1 DNA binding. Gel retardation and chromatin immunoprecipitation assays confirm that POU forms a complex with CREB bound to the cyclin D1 CRE. In solution, CREB interaction with POU requires the CREB Q2 domain and, notably, occurs with CREB that is not phosphorylated on Ser 133. Accordingly, Oct-1 also potently enhances transcriptional activation mediated by a Ser133Ala CREB mutant. Oct-1/CREB synergy is not diminished by the adenovirus E1A 12S protein, a repressor of CBP coactivator function. In contrast, E1A strongly represses CBP-enhanced transactivation by CREB phosphorylated on Ser 133. Our observation that Oct-1 potentiates CREB-dependent cyclin D1 transcriptional activity independently of Ser 133 phosphorylation and E1A-sensitive coactivator function offers a new paradigm for the regulation of cyclin D1 induction by proliferative signals.
    MeSH term(s) Breast Neoplasms ; CREB-Binding Protein ; Cyclic AMP Response Element-Binding Protein/metabolism ; Cyclin D1/genetics ; Cyclin D1/metabolism ; DNA-Binding Proteins/metabolism ; Genes, Reporter ; Host Cell Factor C1 ; Humans ; Nuclear Proteins/metabolism ; Octamer Transcription Factor-1 ; Phosphoproteins/metabolism ; Promoter Regions, Genetic ; Protein Binding ; Protein Structure, Tertiary ; Recombinant Fusion Proteins/genetics ; Recombinant Fusion Proteins/metabolism ; Trans-Activators/metabolism ; Transcription Factors/metabolism ; Transcription, Genetic ; Tumor Cells, Cultured
    Chemical Substances Cyclic AMP Response Element-Binding Protein ; DNA-Binding Proteins ; HCFC1 protein, human ; Host Cell Factor C1 ; Nuclear Proteins ; Octamer Transcription Factor-1 ; POU2F1 protein, human ; Phosphoproteins ; Recombinant Fusion Proteins ; Trans-Activators ; Transcription Factors ; Cyclin D1 (136601-57-5) ; CREB-Binding Protein (EC 2.3.1.48) ; CREBBP protein, human (EC 2.3.1.48)
    Language English
    Publishing date 2001-10-13
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 779397-2
    ISSN 1098-5549 ; 0270-7306
    ISSN (online) 1098-5549
    ISSN 0270-7306
    DOI 10.1128/MCB.22.22.7769-7779.2002
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Limits to Gauge Coupling in the Dark Sector Set by the Nonobservation of Instanton-Induced Decay of Super-Heavy Dark Matter in the Pierre Auger Observatory Data.

    Abreu, P / Aglietta, M / Albury, J M / Allekotte, I / Almeida Cheminant, K / Almela, A / Aloisio, R / Alvarez-Muñiz, J / Alves Batista, R / Ammerman Yebra, J / Anastasi, G A / Anchordoqui, L / Andrada, B / Andringa, S / Aramo, C / Araújo Ferreira, P R / Arnone, E / Arteaga Velázquez, J C / Asorey, H /
    Assis, P / Avila, G / Avocone, E / Badescu, A M / Bakalova, A / Balaceanu, A / Barbato, F / Bellido, J A / Berat, C / Bertaina, M E / Bhatta, G / Biermann, P L / Binet, V / Bismark, K / Bister, T / Biteau, J / Blazek, J / Bleve, C / Blümer, J / Boháčová, M / Boncioli, D / Bonifazi, C / Bonneau Arbeletche, L / Borodai, N / Botti, A M / Brack, J / Bretz, T / Brichetto Orchera, P G / Briechle, F L / Buchholz, P / Bueno, A / Buitink, S / Buscemi, M / Büsken, M / Caballero-Mora, K S / Caccianiga, L / Canfora, F / Caracas, I / Caruso, R / Castellina, A / Catalani, F / Cataldi, G / Cazon, L / Cerda, M / Chinellato, J A / Chudoba, J / Chytka, L / Clay, R W / Cobos Cerutti, A C / Colalillo, R / Coleman, A / Coluccia, M R / Conceição, R / Condorelli, A / Consolati, G / Contreras, F / Convenga, F / Correia Dos Santos, D / Covault, C E / Dasso, S / Daumiller, K / Dawson, B R / Day, J A / de Almeida, R M / de Jesús, J / de Jong, S J / de Mello Neto, J R T / De Mitri, I / de Oliveira, J / de Oliveira Franco, D / de Palma, F / de Souza, V / De Vito, E / Del Popolo, A / Del Río, M / Deligny, O / Deval, L / di Matteo, A / Dobre, M / Dobrigkeit, C / D'Olivo, J C / Domingues Mendes, L M / Dos Anjos, R C / Dova, M T / Ebr, J / Engel, R / Epicoco, I / Erdmann, M / Escobar, C O / Etchegoyen, A / Falcke, H / Farmer, J / Farrar, G / Fauth, A C / Fazzini, N / Feldbusch, F / Fenu, F / Fick, B / Figueira, J M / Filipčič, A / Fitoussi, T / Fodran, T / Fujii, T / Fuster, A / Galea, C / Galelli, C / García, B / Garcia Vegas, A L / Gemmeke, H / Gesualdi, F / Gherghel-Lascu, A / Ghia, P L / Giaccari, U / Giammarchi, M / Glombitza, J / Gobbi, F / Gollan, F / Golup, G / Gómez Berisso, M / Gómez Vitale, P F / Gongora, J P / González, J M / González, N / Goos, I / Góra, D / Gorgi, A / Gottowik, M / Grubb, T D / Guarino, F / Guedes, G P / Guido, E / Hahn, S / Hamal, P / Hampel, M R / Hansen, P / Harari, D / Harvey, V M / Haungs, A / Hebbeker, T / Heck, D / Hill, G C / Hojvat, C / Hörandel, J R / Horvath, P / Hrabovský, M / Huege, T / Insolia, A / Isar, P G / Janecek, P / Johnsen, J A / Jurysek, J / Kääpä, A / Kampert, K H / Keilhauer, B / Khakurdikar, A / Kizakke Covilakam, V V / Klages, H O / Kleifges, M / Kleinfeller, J / Knapp, F / Kunka, N / Lago, B L / Langner, N / Leigui de Oliveira, M A / Lenok, V / Letessier-Selvon, A / Lhenry-Yvon, I / Lo Presti, D / Lopes, L / López, R / Lu, L / Luce, Q / Lundquist, J P / Machado Payeras, A / Mancarella, G / Mandat, D / Manning, B C / Manshanden, J / Mantsch, P / Marafico, S / Mariani, F M / Mariazzi, A G / Mariş, I C / Marsella, G / Martello, D / Martinelli, S / Martínez Bravo, O / Mastrodicasa, M / Mathes, H J / Matthews, J / Matthiae, G / Mayotte, E / Mayotte, S / Mazur, P O / Medina-Tanco, G / Melo, D / Menshikov, A / Michal, S / Micheletti, M I / Miramonti, L / Mollerach, S / Montanet, F / Morejon, L / Morello, C / Mostafá, M / Müller, A L / Muller, M A / Mulrey, K / Mussa, R / Muzio, M / Namasaka, W M / Nasr-Esfahani, A / Nellen, L / Nicora, G / Niculescu-Oglinzanu, M / Niechciol, M / Nitz, D / Norwood, I / Nosek, D / Novotny, V / Nožka, L / Nucita, A / Núñez, L A / Oliveira, C / Palatka, M / Pallotta, J / Papenbreer, P / Parente, G / Parra, A / Pawlowsky, J / Pech, M / Pękala, J / Pelayo, R / Peña-Rodriguez, J / Pereira Martins, E E / Perez Armand, J / Pérez Bertolli, C / Perrone, L / Petrera, S / Petrucci, C / Pierog, T / Pimenta, M / Pirronello, V / Platino, M / Pont, B / Pothast, M / Privitera, P / Prouza, M / Puyleart, A / Querchfeld, S / Rautenberg, J / Ravignani, D / Reininghaus, M / Ridky, J / Riehn, F / Risse, M / Rizi, V / Rodrigues de Carvalho, W / Rodriguez Rojo, J / Roncoroni, M J / Rossoni, S / Roth, M / Roulet, E / Rovero, A C / Ruehl, P / Saftoiu, A / Saharan, M / Salamida, F / Salazar, H / Salina, G / Sanabria Gomez, J D / Sánchez, F / Santos, E M / Santos, E / Sarazin, F / Sarmento, R / Sarmiento-Cano, C / Sato, R / Savina, P / Schäfer, C M / Scherini, V / Schieler, H / Schimassek, M / Schimp, M / Schlüter, F / Schmidt, D / Scholten, O / Schoorlemmer, H / Schovánek, P / Schröder, F G / Schulte, J / Schulz, T / Sciutto, S J / Scornavacche, M / Segreto, A / Sehgal, S / Shellard, R C / Sigl, G / Silli, G / Sima, O / Smau, R / Šmída, R / Sommers, P / Soriano, J F / Squartini, R / Stadelmaier, M / Stanca, D / Stanič, S / Stasielak, J / Stassi, P / Streich, A / Suárez-Durán, M / Sudholz, T / Suomijärvi, T / Supanitsky, A D / Szadkowski, Z / Tapia, A / Taricco, C / Timmermans, C / Tkachenko, O / Tobiska, P / Todero Peixoto, C J / Tomé, B / Torrès, Z / Travaini, A / Travnicek, P / Trimarelli, C / Tueros, M / Ulrich, R / Unger, M / Vaclavek, L / Vacula, M / Valdés Galicia, J F / Valore, L / Varela, E / Vásquez-Ramírez, A / Veberič, D / Ventura, C / Vergara Quispe, I D / Verzi, V / Vicha, J / Vink, J / Vorobiov, S / Wahlberg, H / Watanabe, C / Watson, A A / Weindl, A / Wiencke, L / Wilczyński, H / Wittkowski, D / Wundheiler, B / Yushkov, A / Zapparrata, O / Zas, E / Zavrtanik, D / Zavrtanik, M / Zehrer, L

    Physical review letters

    2023  Volume 130, Issue 6, Page(s) 61001

    Abstract: Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at ... ...

    Abstract Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α_{X}≲0.09, for 10^{9}≲M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}≳3×10^{13}  GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.
    Language English
    Publishing date 2023-02-20
    Publishing country United States
    Document type Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.130.061001
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  10. Article: Activation mechanism of the heterodimeric GABA(B) receptor.

    Pin, Jean-Philippe / Kniazeff, Julie / Binet, Virginie / Liu, Jianfeng / Maurel, Damien / Galvez, Thierry / Duthey, Béatrice / Havlickova, Michaela / Blahos, Jaroslav / Prézeau, Laurent / Rondard, Philippe

    Biochemical pharmacology

    2004  Volume 68, Issue 8, Page(s) 1565–1572

    Abstract: The GABA(B) receptor was the first heteromeric G-protein coupled receptor (GPCR) identified. Indeed, both GABA(B1) and GABA(B2) subunits appear necessary to get a functional GABA(B) receptor. Soon after the cloning of both subunits, it was demonstrated ... ...

    Abstract The GABA(B) receptor was the first heteromeric G-protein coupled receptor (GPCR) identified. Indeed, both GABA(B1) and GABA(B2) subunits appear necessary to get a functional GABA(B) receptor. Soon after the cloning of both subunits, it was demonstrated that GABA(B2) was required for GABA(B1) to reach the cell surface. However, even a mutated GABA(B1) able to reach the cell surface is not functional alone despite its ability to bind GABA(B) ligands. This clearly demonstrated that GABA(B2) is not only required for the correct trafficking of GABA(B1) but also for the correct functioning of the receptor. In the present review article, we will summarize our actual knowledge of the specific role of each subunit in ligand recognition, intramolecular transduction, G-protein activation and allosteric modulation. We will show that the GABA(B) receptor is an heterodimer (not an hetero-oligomer), that agonists bind in GABA(B1), whereas GABA(B2) controls agonist affinity and is responsible for G-protein coupling. Finally, we will show that the recently identified positive allosteric modulator CGP7930 acts as a direct activator of the heptahelical domain of GABA(B2), being therefore the first GABA(B2) ligand identified so far.
    MeSH term(s) Allosteric Regulation ; Animals ; Baclofen/pharmacology ; Dimerization ; GABA Agonists/pharmacology ; GTP-Binding Proteins/metabolism ; Humans ; Protein Binding ; Protein Structure, Tertiary ; Protein Subunits ; Receptors, G-Protein-Coupled/metabolism ; Receptors, GABA-B/drug effects ; Receptors, GABA-B/metabolism ; gamma-Aminobutyric Acid/metabolism
    Chemical Substances GABA Agonists ; Protein Subunits ; Receptors, G-Protein-Coupled ; Receptors, GABA-B ; gamma-Aminobutyric Acid (56-12-2) ; GTP-Binding Proteins (EC 3.6.1.-) ; Baclofen (H789N3FKE8)
    Language English
    Publishing date 2004-10-15
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 208787-x
    ISSN 1873-2968 ; 0006-2952
    ISSN (online) 1873-2968
    ISSN 0006-2952
    DOI 10.1016/j.bcp.2004.06.035
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