1
|
Casazza G, Macrì C, Dagnino D, Guerrina M, Juin M, Minuto L, Thompson JD, Baumel A, Médail F. When ecological marginality is not geographically peripheral: exploring genetic predictions of the centre-periphery hypothesis in the endemic plant Lilium pomponium. PeerJ 2021; 9:e11039. [PMID: 33854841 PMCID: PMC7955672 DOI: 10.7717/peerj.11039] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 02/09/2021] [Indexed: 01/14/2023] Open
Abstract
Background Quantifying variation of genetic traits over the geographical range of species is crucial for understanding the factors driving their range dynamics. The center-periphery hypothesis postulates, and many studies support, the idea that genetic diversity decreases and genetic differentiation increases toward the geographical periphery due to population isolation. The effects of environmental marginality on genetic variation has however received much less attention. Methods We tested the concordance between geographical and environmental gradients and the genetic predictions of center-periphery hypothesis for endemic Lilium pomponium in the southern Alps. Results We found little evidence for concordance between genetic variation and both geographical and environmental gradients. Although the prediction of increased differentiation at range limits is met, genetic diversity does not decrease towards the geographical periphery. Increased differentiation among peripheral populations, that are not ecologically marginal, may be explained by a decrease in habitat availability that reduces population connectivity. In contrast, a decrease of genetic diversity along environmental but not geographical gradients may be due to the presence of low quality habitats in the different parts of the range of a species that reduce effective population size or increase environmental constraints. As a result, environmental factors may affect population dynamics irrespective of distance from the geographical center of the range. In such situations of discordance between geographical and environmental gradients, the predictions of decreasing genetic diversity and increasing differentiation toward the geographical periphery may not be respected.
Collapse
Affiliation(s)
- Gabriele Casazza
- Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE), Aix Marseille Université, Avignon Université, CNRS, IRD. Technopôle de l'Arbois-Méditerranée, Aix en Provence, France
| | - Carmelo Macrì
- Department for the Earth, Environment and Life Sciences (DISTAV), University of Genoa, Genova, Italy
| | - Davide Dagnino
- Department for the Earth, Environment and Life Sciences (DISTAV), University of Genoa, Genova, Italy
| | - Maria Guerrina
- Department for the Earth, Environment and Life Sciences (DISTAV), University of Genoa, Genova, Italy
| | - Marianick Juin
- Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE), Aix Marseille Université, Avignon Université, CNRS, IRD. Technopôle de l'Arbois-Méditerranée, Aix en Provence, France
| | - Luigi Minuto
- Department for the Earth, Environment and Life Sciences (DISTAV), University of Genoa, Genova, Italy
| | - John D Thompson
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, Montpellier, France
| | - Alex Baumel
- Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE), Aix Marseille Université, Avignon Université, CNRS, IRD. Technopôle de l'Arbois-Méditerranée, Aix en Provence, France
| | - Frédéric Médail
- Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE), Aix Marseille Université, Avignon Université, CNRS, IRD. Technopôle de l'Arbois-Méditerranée, Aix en Provence, France
| |
Collapse
|
2
|
Viruel J, Haguenauer A, Juin M, Mirleau F, Bouteiller D, Boudagher‐Kharrat M, Ouahmane L, La Malfa S, Médail F, Sanguin H, Nieto Feliner G, Baumel A. Advances in genotyping microsatellite markers through sequencing and consequences of scoring methods for Ceratonia siliqua (Leguminosae). Appl Plant Sci 2018; 6:e01201. [PMID: 30598859 PMCID: PMC6303155 DOI: 10.1002/aps3.1201] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/28/2018] [Indexed: 05/25/2023]
Abstract
PREMISE OF THE STUDY Simple sequence repeat (SSR) or microsatellite markers have been used in a broad range of studies mostly scoring alleles on the basis of amplicon size as a proxy for the number of repeat units of an SSR motif. However, additional sources of variation within the SSR or in the flanking regions have largely remained undetected. METHODS In this study, we implemented a next-generation sequencing-based genotyping approach in a newly characterized set of 18 nuclear SSR markers for the carob tree, Ceratonia siliqua. Our aim was to evaluate the effect of three different methods of scoring molecular variation present within microsatellite markers on the genetic diversity and structure results. RESULTS The analysis of the sequences of 77 multilocus genotypes from four populations revealed SSR variation and additional sources of polymorphism in 87% of the loci analyzed (42 single-nucleotide polymorphisms and five insertion/deletion polymorphisms), as well as divergent paralog copies in two loci. Ignoring sequence variation under standard amplicon size genotyping resulted in incorrect identification of 69% of the alleles, with important effects on the genetic diversity and structure estimates. DISCUSSION Next-generation sequencing allows the detection and scoring of SSRs, single-nucleotide polymorphisms, and insertion/deletion polymorphisms to increase the resolution of population genetic studies.
Collapse
Affiliation(s)
- Juan Viruel
- Royal Botanic GardensKew, RichmondSurreyTW9 3DSUnited Kingdom
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE) [IMBE is sponsored by Aix Marseille University, Avignon University, Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)]Station marine d'Endoume, Chemin de la Batterie des LionsFR‐13007MarseilleFrance
| | - Anne Haguenauer
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE) [IMBE is sponsored by Aix Marseille University, Avignon University, Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)]Station marine d'Endoume, Chemin de la Batterie des LionsFR‐13007MarseilleFrance
| | - Marianick Juin
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE) [IMBE is sponsored by Aix Marseille University, Avignon University, Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)]Station marine d'Endoume, Chemin de la Batterie des LionsFR‐13007MarseilleFrance
| | - Fatma Mirleau
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE) [IMBE is sponsored by Aix Marseille University, Avignon University, Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)]Station marine d'Endoume, Chemin de la Batterie des LionsFR‐13007MarseilleFrance
| | - Delphine Bouteiller
- Institut du Cerveau et de la Moelle épinière (ICM)Hôpital Pitié Salpêtrière47 Boulevard de l'Hôpital75013ParisFrance
| | - Magda Boudagher‐Kharrat
- Laboratoire Caractérisation Génétique des PlantesFaculté des sciencesUniversité Saint‐JosephB.P. 11‐514 Riad El SolhBeirut1107 2050Lebanon
| | - Lahcen Ouahmane
- Laboratoire d'Ecologie et EnvironnementFaculté des Sciences SemlaliaUniversité Cadi AyyadMarrakeshMorocco
| | - Stefano La Malfa
- Dipartimento di Agricoltura, Alimentazione e Ambiente (Di3A)Università degli Studi di CataniaVia Valdisavoia 595123CataniaItaly
| | - Frédéric Médail
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE) [IMBE is sponsored by Aix Marseille University, Avignon University, Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)]Station marine d'Endoume, Chemin de la Batterie des LionsFR‐13007MarseilleFrance
| | - Hervé Sanguin
- Centre de coopération internationale en recherche agronomique pour le développement (CIRAD)Laboratoire des Symbioses Tropicales et Méditerranéennes (LSTM)MontpellierFrance
- LSTM [LSTM is sponsored by University of Montpellier, CIRAD, IRD, INRA, Montpellier SupAgro]TA A‐82/J Campus International de BaillarguetFR‐34398Montpellier CEDEX 5France
| | | | - Alex Baumel
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE) [IMBE is sponsored by Aix Marseille University, Avignon University, Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)]Station marine d'Endoume, Chemin de la Batterie des LionsFR‐13007MarseilleFrance
| |
Collapse
|
3
|
Pouget M, Youssef S, Migliore J, Juin M, Médail F, Baumel A. Phylogeography sheds light on the central-marginal hypothesis in a Mediterranean narrow endemic plant. Ann Bot 2013; 112:1409-1420. [PMID: 23962409 PMCID: PMC3806523 DOI: 10.1093/aob/mct183] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 07/03/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND AND AIMS Understanding the factors that shape variation in genetic diversity across the geographic ranges of species is an important challenge in the effort to conserve evolutionary processes sustaining biodiversity. The historical influences leading to a central-marginal organization of genetic diversity have been explored for species whose range is known to have expanded from refugia after glacial events. However, this question has rarely been addressed for Mediterranean endemic plants of azonal habitats such as rocky slopes or screes. In this context, this comprehensive study examined molecular and field data from Arenaria provincialis (Caryophyllaceae), a narrow endemic plant of south-eastern France. METHODS Across the whole geographic range, an investigation was made of whether high levels of abundance and genetic diversity (estimated from amplified fragment length polymorphism markers) are centrally distributed, to evaluate the relevance of the central-marginal hypothesis. Phylogeographic patterns inferred from chloroplast DNA (cpDNA) were used, applying Bayesian methods to test the influence of past biogeographic events. Multivariate analysis combining phylogeographic and ecological data was used to reveal the historical and ecological distinctiveness of populations. KEY RESULTS Despite the narrow distribution of A. provincialis, a high level of nucleotide variation is found within cpDNA loci, supporting its persistence throughout the Pleistocene period. The area characterized by the highest genetic diversity is centrally located. Structured phylogeography and Bayesian factor analysis supported the hypothesis that the central area of the distribution was the source of both westward and eastward migrations, probably during arid periods of the Pleistocene, and more recently was a crossroads of backward migrations. By contrast, the two areas located today at the range limits are younger, have reduced genetic diversity and are marginal in the ecological gradients. CONCLUSIONS This study highlights a case of strong population distinctiveness within a narrow range. Phylogeography sheds light on the historical role of the areas centrally situated in the distribution. The current range size and abundance patterns are not sufficient to predict the organization of genetic diversity.
Collapse
Affiliation(s)
- Marine Pouget
- Aix-Marseille Université, Institut Méditerranéen de Biodiversité et d'Ecologie (IMBE, UMR CNRS 7263), Technopôle de l'Environnement Arbois-Méditerranée, BP 80, 13545 Aix-en-Provence cedex 04, France
| | - Sami Youssef
- Faculty of Agriculture and Forestry, University of Duhok, Kurdistan Region, Iraq
| | - Jérémy Migliore
- Aix-Marseille Université, Institut Méditerranéen de Biodiversité et d'Ecologie (IMBE, UMR CNRS 7263), Technopôle de l'Environnement Arbois-Méditerranée, BP 80, 13545 Aix-en-Provence cedex 04, France
| | - Marianick Juin
- Aix-Marseille Université, Institut Méditerranéen de Biodiversité et d'Ecologie (IMBE, UMR CNRS 7263), Technopôle de l'Environnement Arbois-Méditerranée, BP 80, 13545 Aix-en-Provence cedex 04, France
| | - Frédéric Médail
- Aix-Marseille Université, Institut Méditerranéen de Biodiversité et d'Ecologie (IMBE, UMR CNRS 7263), Technopôle de l'Environnement Arbois-Méditerranée, BP 80, 13545 Aix-en-Provence cedex 04, France
| | - Alex Baumel
- Aix-Marseille Université, Institut Méditerranéen de Biodiversité et d'Ecologie (IMBE, UMR CNRS 7263), Technopôle de l'Environnement Arbois-Méditerranée, BP 80, 13545 Aix-en-Provence cedex 04, France
| |
Collapse
|
4
|
Migliore J, Baumel A, Juin M, Fady B, Roig A, Duong N, Médail F. Surviving in mountain climate refugia: new insights from the genetic diversity and structure of the relict shrub Myrtus nivellei (Myrtaceae) in the Sahara Desert. PLoS One 2013; 8:e73795. [PMID: 24058489 PMCID: PMC3776782 DOI: 10.1371/journal.pone.0073795] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 07/23/2013] [Indexed: 11/27/2022] Open
Abstract
The identification of past glacial refugia has become a key topic for conservation under environmental change, since they contribute importantly to shaping current patterns of biodiversity. However, little attention has been paid so far to interglacial refugia despite their key role for the survival of relict species currently occurring in climate refugia. Here, we focus on the genetic consequences of range contraction on the relict populations of the evergreen shrub Myrtus nivellei, endemic in the Saharan mountains since at least the end of the last Green Sahara period, around 5.5 ka B.P. Multilocus genotypes (nuclear microsatellites and AFLP) were obtained from 215 individuals collected from 23 wadis (temporary rivers) in the three main mountain ranges in southern Algeria (the Hoggar, Tassili n'Ajjer and Tassili n'Immidir ranges). Identical genotypes were found in several plants growing far apart within the same wadis, a pattern taken as evidence of clonality. Multivariate analyses and Bayesian clustering revealed that genetic diversity was mainly structured among the mountain ranges, while low isolation by distance was observed within each mountain range. The range contraction induced by the last episode of aridification has likely increased the genetic isolation of the populations of M. nivellei, without greatly affecting the genetic diversity of the species as a whole. The pattern of genetic diversity observed here suggests that high connectivity may have prevailed during humid periods, which is consistent with recent paleoenvironmental reconstructions.
Collapse
Affiliation(s)
- Jérémy Migliore
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Aix-Marseille Université, UMR CNRS 7263/IRD 237/Avignon Université, Campus Aix - Technopôle de l’Environnement Arbois-Méditerranée, Aix-en-Provence, France
| | - Alex Baumel
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Aix-Marseille Université, UMR CNRS 7263/IRD 237/Avignon Université, Campus Aix - Technopôle de l’Environnement Arbois-Méditerranée, Aix-en-Provence, France
| | - Marianick Juin
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Aix-Marseille Université, UMR CNRS 7263/IRD 237/Avignon Université, Campus Aix - Technopôle de l’Environnement Arbois-Méditerranée, Aix-en-Provence, France
| | - Bruno Fady
- INRA, UR 629, Ecologie des Forêts Méditerranéennes (URFM), Site Agroparc - Domaine Saint Paul, Avignon, France
| | - Anne Roig
- INRA, UR 629, Ecologie des Forêts Méditerranéennes (URFM), Site Agroparc - Domaine Saint Paul, Avignon, France
| | - Nathalie Duong
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Aix-Marseille Université, UMR CNRS 7263/IRD 237/Avignon Université, Campus Aix - Technopôle de l’Environnement Arbois-Méditerranée, Aix-en-Provence, France
| | - Frédéric Médail
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Aix-Marseille Université, UMR CNRS 7263/IRD 237/Avignon Université, Campus Aix - Technopôle de l’Environnement Arbois-Méditerranée, Aix-en-Provence, France
| |
Collapse
|
5
|
Campagne P, Baumel A, Affre L, Juin M, Duong N, Roche P, Tatoni T. Genetic signs of connectivity in Primula vulgaris (Primulaceae) in a hedgerow network landscape. C R Biol 2009; 332:652-61. [DOI: 10.1016/j.crvi.2009.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Revised: 03/16/2009] [Accepted: 03/17/2009] [Indexed: 10/20/2022]
|
6
|
Renault L, Essono S, Juin M, Boquet D, Grassi J, Bourne Y, Marchot P. Structural insights into AChE inhibition by monoclonal antibodies. Chem Biol Interact 2006; 157-158:397-400. [PMID: 16429535 DOI: 10.1016/j.cbi.2005.10.073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The target sites of three inhibitory monoclonal antibodies, Elec403, 408 and 410, on eel AChE have been defined previously. Elec403 and 410 are directed toward distinct but overlapping epitopes at the enzyme peripheral site, while Elec408 binds to a distinct regulatory site on the enzyme surface, where the "back door" may be located. Elec410 also inhibits Bunganus fasciatus AChE. To investigate the molecular determinants for AChE inhibition by these antibodies, we have cloned and sequenced the IgGs, generated, purified, characterized the Fab molecules, and initiated crystallographic and theoretical modeling studies. Preliminary data are presented.
Collapse
Affiliation(s)
- Ludovic Renault
- Ingénierie des Protéines, CNRS, IFR Jean Roche, Université de la Méditerranée, Marseille, France
| | | | | | | | | | | | | |
Collapse
|
7
|
Bourne Y, Hasper AA, Chahinian H, Renault L, Juin M, de Graaff LH, Marchot P. (27) A. niger protein “EstA”, perhaps a new electrotactin, defines a new class of fungal esterases within the α/β hydrolase fold superfamily. Chem Biol Interact 2005; 157-158:395-6. [PMID: 16429533 DOI: 10.1016/j.cbi.2005.10.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Protein EstA from Aspergillus niger was characterized through a multifaced approach involving molecular biology, bioinformatics, biophysical, biochemical and enzymatical analyses. EstA was identified as the lead member, within the superfamily of proteins with an alpha/beta-hydrolase fold, of a new class of fungal esterases that also contains predicted homologs from other fungus species of known broad host-range pathogenicity.
Collapse
Affiliation(s)
- Yves Bourne
- Ingénierie des Protéines, IFR Jean Roche, Université de la Méditerranée, CNRS, Marseille, France
| | | | | | | | | | | | | |
Collapse
|
8
|
Bourne Y, Hasper AA, Chahinian H, Juin M, De Graaff LH, Marchot P. Aspergillus niger Protein EstA Defines a New Class of Fungal Esterases within the α/β Hydrolase Fold Superfamily of Proteins. Structure 2004; 12:677-87. [PMID: 15062090 DOI: 10.1016/j.str.2004.03.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2003] [Revised: 01/22/2004] [Accepted: 01/23/2004] [Indexed: 10/26/2022]
Abstract
From the fungus Aspergillus niger, we identified a new gene encoding protein EstA, a member of the alpha/beta-hydrolase fold superfamily but of unknown substrate specificity. EstA was overexpressed and its crystal structure was solved by molecular replacement using a lipase-acetylcholinesterase chimera template. The 2.1 A resolution structure of EstA reveals a canonical Ser/Glu/His catalytic triad located in a small pocket at the bottom of a large solvent-accessible, bowl-shaped cavity. Potential substrates selected by manual docking procedures were assayed for EstA activity. Consistent with the pocket geometry, preference for hydrolysis of short acyl/propyl chain substrates was found. Identification of close homologs from the genome of other fungi, of which some are broad host-range pathogens, defines EstA as the first member of a novel class of fungal esterases within the superfamily. Hence the structure of EstA constitutes a lead template in the design of new antifungal agents directed toward its pathogenic homologs.
Collapse
Affiliation(s)
- Yves Bourne
- Architecture et Fonction des Macromolécules Biologiques, CNRS UMR-6098, 31 Chemin Joseph Aiguier, F-13402 Marseille Cedex 20, France.
| | | | | | | | | | | |
Collapse
|
9
|
Clot-Faybesse O, Juin M, Rochat H, Devaux C. Monoclonal antibodies against the Androctonus australis hector scorpion neurotoxin I: characterisation and use for venom neutralisation. FEBS Lett 1999; 458:313-8. [PMID: 10570931 DOI: 10.1016/s0014-5793(99)01179-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of monoclonal antibodies (mAbs) specific for the alpha-neurotoxin I (Aah I) from the venom of the dangerous Androctonus australis hector scorpion were obtained using carrier protein-coupled toxin. Competitive RIA, receptor assays and mouse toxicity tests were performed to characterise mAbs in terms of affinity and neutralisation. Cross-reactivity studies and two-site ELISA results allowed some classification of mAbs into three groups. One mAb, 9C2, was particularly interesting since it recognised the parent toxin I with a K(D) of 0.15 nM and was also reactive with toxins of the same immunological group. Its ability to neutralise the toxic effect of the parent toxin and the venom fraction has been investigated. This anti-Aah I mAb 9C2, associated with anti-Aah II mAb 4C1, provides a valuable tool to neutralise the toxicity of the venom.
Collapse
Affiliation(s)
- O Clot-Faybesse
- CNRS UMR 6560, Ingénierie des Protéines, IFR Jean Roche, Université Méditerranée, Faculté de Médecine-Nord, BD P. Dramard, Marseille, France
| | | | | | | |
Collapse
|
10
|
Abstract
BACKGROUND Adenosine is a powerful natural vasodilator that participates in the control of cerebral and meningeal blood flow. In this context, it could be involved in the pathophysiology of migraine, since it was previously reported that intravenous adenosine can precipitate crises in migraine patients. METHODS We have investigated circulating adenosine levels in 12 patients suffering from migraine without aura, during crises and in crisis-free periods, and have compared the levels noted to those of a population of 10 controls. To determine if there are interactions between adenosine and serotonin, we examined the effect of adenosine and antagonists on the uptake and the release of (14C) serotonin by platelets. RESULTS AND CONCLUSION We have reached a dual conclusion: 1) during migraine headaches there is an increase (mean 68%) in circulating adenosine levels and this increase may participate in cephalalgia; 2) activation of A2 receptors by adenosine causes a dose-dependent serotonin uptake by platelets. This inhibition of uptake could participate in the rapid elimination of serotonin in migraine sufferers. As a result of this, the use of adenosine antagonists could be an effective complementary treatment for migraine.
Collapse
Affiliation(s)
- R Guieu
- UMR CNRS 6560, Faculté de Médecine Secteur Nord, Marseille, France
| | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Devaux C, Clot-Faybesse O, Juin M, Mabrouk K, Sabatier JM, El Ayeb M, Rochat H. Neutralizing polyclonal and monoclonal antibodies against scorpion toxin obtained by using a non-toxic analogue. Toxicon 1997. [DOI: 10.1016/s0041-0101(97)90093-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
12
|
Devaux C, Clot-Faybesse O, Juin M, Mabrouk K, Sabatier JM, Rochat H. Monoclonal antibodies neutralizing the toxin II from Androctonus australis hector scorpion venom: usefulness of a synthetic, non-toxic analog. FEBS Lett 1997; 412:456-60. [PMID: 9276446 DOI: 10.1016/s0014-5793(97)00826-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Scorpion venom contains toxins that act on ion channels. Some are responsible for the noxious effects observed when people are stung by scorpions. The study of the neutralization of these molecules and the production of monoclonal antibodies (mAbs) should prove valuable. Toxin II from Androctonus australis hector scorpion (AahII) is one of the most potent toxins and has been well-characterized and studied. Producing mAbs against such molecules is often difficult due to their toxicity. We used a synthetic, non-toxic analog, (Abu)8-AahII, to obtain mAbs which recognize and neutralize the native toxin AahII. Sets of peptides spanning the entire sequence of AahII were assayed to identify the binding sites of the mAbs. The various mAbs recognized only the largest peptides (12-17 residues). They recognized peptides corresponding to different parts of the AahII sequence, suggesting that several regions of the (Abu)8-AahII sequence mimic AahII epitopes and then elicit mAbs directed against toxin.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/biosynthesis
- Antibodies, Monoclonal/chemistry
- Binding Sites, Antibody
- Binding, Competitive/immunology
- Epitope Mapping
- Female
- Hybridomas/metabolism
- Injections, Intraperitoneal
- Injections, Intraventricular
- Injections, Subcutaneous
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Molecular Sequence Data
- Neurotoxins/chemical synthesis
- Neurotoxins/immunology
- Neurotoxins/toxicity
- Peptides/chemical synthesis
- Peptides/immunology
- Rats
- Reptilian Proteins
- Scorpion Venoms/chemical synthesis
- Scorpion Venoms/immunology
- Scorpion Venoms/toxicity
- Synaptosomes/immunology
- Synaptosomes/metabolism
Collapse
Affiliation(s)
- C Devaux
- CNRS UMR 6560, Laboratoire d'Ingénierie des Protéines, Faculté de Médecine-Nord, Marseille, France.
| | | | | | | | | | | |
Collapse
|
13
|
Abstract
BACKGROUND In animals and in humans, stress is known to be accompanied by increased beta-endorphin secretion. METHODS Blood samples from 47 patients in a state of stress induced by multiple trauma were assessed for beta-endorphin concentration by radioimmunoassays. RESULTS We show that there is a clearcut correlation (Spearman's R = 0.72, P = 2.1 x 10(-6) between the level of consciousness evaluated with the Glasgow score and levels of circulating beta-endorphin. In addition, beta-endorphin levels are higher than normal in patients with Glasgow coma with scores higher than seven, and lower than normal in those with Glasgow coma scores of seven or less. Finally, in the complete absence of stress (shown by the lack of brain activity in six irreversible coma patients), there is a severe drop in the level of circulating beta-endorphin. CONCLUSION beta-endorphin serum levels correlate with the state of consciousness of multiple trauma patients.
Collapse
Affiliation(s)
- R Guieu
- Laboratoire de Biochimie, CNRS URA 1455, Faculté de Médecine Secteur Nord, Marseille, France
| | | | | | | | | | | |
Collapse
|
14
|
Devaux C, Juin M, Mansuelle P, Granier C. Fine molecular analysis of the antigenicity of the Androctonus australis hector scorpion neurotoxin II: a new antigenic epitope disclosed by the Pepscan method. Mol Immunol 1993; 30:1061-8. [PMID: 7690110 DOI: 10.1016/0161-5890(93)90152-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A set of 58 overlapping rod-bound peptides was used to map the antigenic reactivity pattern of a 64-residue neurotoxin (AaH II) from the venom of the scorpion Androctonus australis hector. Five anti-toxin rabbit antisera were assayed serially for their capacity to bind to each peptide in the set. Six regions of antigenic reactivity were thus identified (sequences: 1-8, 4-12, 27-35, 39-45, 52-58 and 55-61). When positioned on a 3-D model of the toxin, these regions appeared to correspond to either beta-turn or extended parts of the molecule. The antigenic regions revealed by this technique agree fairly well with those previously mapped on the same toxin by different methods. One discrepancy was, however, that the present study shows the N-terminus to be strongly reactive with anti-toxin antibodies. The antigenicity of this region was confirmed, since rabbit antibodies raised against a synthetic peptide mimicking the sequence 1-8 of the toxin were found to bind the toxin with high efficiency. A fine analysis of the recognition of this region was performed. Alanine-containing analogs of the sequence 1-7 and peptides mimicking the N-terminal of the four main toxins of AaH were probed with anti-toxin and anti-peptide antibodies. Lysine 2, aspartic acid 3 and glycine 4 were shown to be key residues in the recognition of the N-terminal region of the AaH II toxin by anti-toxin antibodies. In contrast, a loose specificity of recognition was shown by one anti-peptide serum which was, in addition, able to recognize the N-termini of all four AaH toxins.
Collapse
Affiliation(s)
- C Devaux
- Laboratoire de Biochimie, CNRS URA 1455, Faculté de Médecine Secteur Nord, Marseille, France
| | | | | | | |
Collapse
|
15
|
Méry J, Granier C, Juin M, Brugidou J. Disulfide linkage to polyacrylic resin for automated Fmoc peptide synthesis. Immunochemical applications of peptide resins and mercaptoamide peptides. Int J Pept Protein Res 1993; 42:44-52. [PMID: 8370643 DOI: 10.1111/j.1399-3011.1993.tb00348.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The use of disulfide bonds for peptide-resin linkage in solid-phase peptide synthesis was investigated using polyacrylic polymers (Expansin) and automated Fmoc methodology. The disulfide moiety was bound to the support either by coupling a protected bifunctional handle or by an original stepwise procedure. Among the three different disulfide handles that were investigated, only the aminoethyldithio-2-isobutyric acid (AEDI) handle was stable enough to achieve peptide synthesis. A series of peptides of up to 10-20 amino acids were prepared in this manner, in good yield and purity. Rapid and quantitative peptide release was obtained by reduction with equimolecular amounts of dithiothreitol at pH 9 or tris(2-carboxymethyl) phosphine at pH 4.5. This allowed direct and rapid coupling of the released cysteamide peptides to an activated protein carrier and the use of free or resin-bound forms of the antigen in immunoassays.
Collapse
Affiliation(s)
- J Méry
- Research Centre for Macromolecular Biochemistry, CNRS, Montpellier, France
| | | | | | | |
Collapse
|
16
|
Abstract
Apamin, a 18-amino acid bee venom toxic peptide specifically blocks a class of Ca(2+)-activated K+ channels. i) Mono 125I-iodoapamin binds to receptor sites in a human neuroglial cell line (C6 line) but not in human cell lines from pancreatic (RIN5F line) and colonic origin (HT29 line). ii) Receptor-bound apamin is still accessible to a large molecule since some anti-apamin monoclonal antibodies recognize apamin when bound to its receptor, both in intact cells of the human C6 glioma line and in rat brain synaptosomal membranes.
Collapse
Affiliation(s)
- M L Defendini
- Laboratoire de Biochimie, Centre National de la Recherche Scientifique, Faculté de Médecine, Marseille, France
| | | | | |
Collapse
|