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Contribution À L'étude De La Régulation Transcriptionnelle Lors Du Cylce Érythrocytaire De Plasmodium Falciparum Par L'analyse Bioinformatique Des Acteurs De Cette Régulation

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Contribution À L'étude De La Régulation Transcriptionnelle Lors Du Cylce Érythrocytaire De Plasmodium Falciparum Par L'analyse Bioinformatique Des Acteurs De Cette Régulation Contribution à l’étude de la régulation transcriptionnelle lors du cylce érythrocytaire de Plasmodium falciparum par l’analyse bioinformatique des acteurs de cette régulation Charlotte Boschet To cite this version: Charlotte Boschet. Contribution à l’étude de la régulation transcriptionnelle lors du cylce érythrocy- taire de Plasmodium falciparum par l’analyse bioinformatique des acteurs de cette régulation. Autre [q-bio.OT]. Université Paris-Diderot - Paris VII, 2006. Français. tel-00082727 HAL Id: tel-00082727 https://tel.archives-ouvertes.fr/tel-00082727 Submitted on 28 Jun 2006 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. UFR de Biologie et Sciences de la Nature INSERM U511 Tour 54/53 – 4ème étage Immunobiologie cellulaire et moléculaire 2 place Jussieu des infections parasitaires 75005 PARIS 91 boulevard de l’Hôpital 75013 PARIS ECOLE DOCTORALE : BIOCHIMIE ET BIOLOGIE MOLECULAIRE THESE DE DOCTORAT pour l’obtention du grade de DOCTEUR DE L’UNIVERSITE DENIS DIDEROT - PARIS 7 Spécialité : ANALYSE DE GENOMES ET MODELISATION MOLECULAIRE présentée publiquement le 26 juin 2006 par Charlotte BOSCHET Contribution à lʹétude de la régulation transcriptionnelle lors du cycle érythrocytaire de Plasmodium falciparum par lʹanalyse bioinformatique des acteurs de cette régulation JURY Pr Catherine ETCHEBEST, Université Paris 7 Président Dr Isabelle CALLEBAUT, CNRS Rapporteur Pr Gilbert DELEAGE, Université Lyon 1 Rapporteur Pr Caroline LE VAN KIM, Université Paris 7 Examinateur Pr Anne-Claude CAMPROUX, Université Paris 7 Examinateur Dr Catherine VAQUERO, INSERM Directeur de thèse A Serge Hazout, qui devait faire partie de mon jury de thèse et que j’aurais aimé remercier pour tout ce qu’il a fait pour moi. Je tiens en tout premier lieu à remercier Isabelle Callebaut, Gilbert Deléage, Anne-Claude Camproux et Caroline Le Van Kim pour avoir accepté cette tâche laborieuse qu'est l'évaluation d'un travail de thèse, ainsi que Catherine Etchebest pour m’avoir si bien conseillé pour la composition de mon jury. Merci à Dominique Mazier pour m’avoir accueilli au sein de l’unité INSERM U511 mais aussi pour m’avoir permis de développer des talents autres que scientifiques. Je remercie Catherine Vaquero pour m’avoir donné l’opportunité de faire cette thèse et pour m’avoir laissé une grande liberté dans mon travail. Je tiens à adresser tous mes remerciements à Sylvie qui a très vite quitté le statut de collègue pour devenir une amie très sincère. Sylvie, merci pour ton soutien et tes paroles réconfortantes, pour ton amitié et ta confiance, pour tous les bons moments passés et à venir. à Delphine et Romain pour leur aide inestimable lors de la rédaction de ce manuscrit et leur réconfort. Delphine, j’ai beaucoup aimé enseigner avec toi et j’espère très sincèrement que cela se reproduira dans l’avenir. Romain, merci pour avoir toujours répondu si rapidement à tous les SOS que j’ai pu lancer et merci pour ton amitié sans faille. à Maryse pour sa bonne humeur, son efficacité, son amitié et toutes les batailles de frites que l’on a pu faire à la piscine et toute la sueur que nous avons évacuée lors des cours de gym. à Philippe, loin des yeux mais pas loin du cœur. à tous les membres de l’U511 avec qui j’ai passé de très bons moments sans oublier ceux qui sont partis vers d’autres horizons : Dorothée, Quentin, Nicolas, Stéphane et Ali. à tous les membres de l’EBGM qui m’ont toujours très bien accueillie et même réconfortée quelques fois. Un merci particulier à Anne qui m’a permis de découvrir une passion le jour où elle m’a demandé si je voulais bien enseigner. à mes amies les grues : Gud, Ludi et Marie, toujours unies malgré l’éloignement, mes amis les poulpes : Anne, France, Flore, Tiénou et Alexis, et mon californien préféré Alex, sans oublier Ninou qui a décoré mon bureau de ses dessins et coloriages dédicacés. Et enfin, mille mercis à mes parents pour m’avoir permis de faire de longues études dans les meilleures conditions possibles. Je n’en serais pas là aujourd’hui s’ils ne m’avaient pas constamment soutenue. TABLE DES MATIERES Table des matières AVANT-PROPOS................................................................................................................................... 10 INTRODUCTION LE PALUDISME ET PLASMODIUM FALCIPARUM................................................................................. 14 I - Historique .................................................................................................................................. 15 II - Le paludisme et les hommes.................................................................................................17 II.1 - Symptômes et complications........................................................................................................ 17 II.2 - Prévention....................................................................................................................................... 20 II.3 - Traitements ..................................................................................................................................... 20 II.4 - Le paludisme dans le monde........................................................................................................ 24 III - Plasmodium falciparum........................................................................................................ 27 III.1 - Le développement de Plasmodium falciparum ........................................................................... 29 III.2 - Le génome de Plasmodium falciparum......................................................................................... 31 LA TRANSCRIPTION ET LA REGULATION TRANSCRIPTIONNELLE CHEZ LES EUCARYOTES .......... 37 I - Structure du matériel génétique chez les eucaryotes......................................................... 38 I.1 - Structure de la chromatine............................................................................................................. 39 I.2 - Définitions d’un gène ..................................................................................................................... 44 I.3 - Structure du promoteur ................................................................................................................. 45 II - La transcription........................................................................................................................ 47 II.1 - L’expression des gènes codant des protéines............................................................................. 47 II.2 - Les ARN polymérases................................................................................................................... 49 II.3 - Le cycle de la transcription par l’ARN polymérase II............................................................... 50 II.4 - Maturation des transcrits.............................................................................................................. 52 III - La régulation de la transcription ........................................................................................ 55 III.1 - Influence de la structure chromatinienne : informations épigénétiques............................... 55 a. Modifications post-traductionnelles des histones : le « code histone »...................... 56 b. Méthylation de l’ADN...................................................................................................... 59 c. Remodelage ATP-dépendant........................................................................................... 59 III.2 - Les séquences cis-régulatrices..................................................................................................... 60 III.3 - Les facteurs de transcription....................................................................................................... 62 a. Protéines à domaine basique ........................................................................................... 64 b. Protéines à motif en doigt de zinc (Zn finger)............................................................... 66 c. Protéines à motif hélice-tour-hélice (HTH) .................................................................... 67 d. Les protéines à architecture β en contact avec le petit sillon....................................... 69 III.4 - Modèle de mécanisme d’activation de la transcription spécifique d’un gène ..................... 70 ETAT DE L’ART SUR PLASMODIUM FALCIPARUM.............................................................................. 73 MATERIELS ET METHODES I - Les différents outils utilisés ................................................................................................... 80 II - Les matériels et méthodes utilisées ..................................................................................... 82 II.1 - Sélection des régions intergéniques ............................................................................................ 82 II.2 - Construction d’une bibliothèque de séquences promotrices..................................................
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