Fiche Projet
Transcription
Fiche Projet
Ecole Doctorale COMPLEXITE DU VIVANT – Fiche Projet CONCOURS Nom et prénom du directeur de thèse (et si besoin du co-directeur) : Laurent Servais Le directeur de thèse et le co-directeur doivent impérativement être habilités à diriger les recherches (HDR) Laurent Servais Coordonnées Tel : 01 44 73 65 44 e-mail : [email protected] Nom et prénom du co-directeur: Piétri-Rouxel France Coordonnées Tel : 01 40 77 96 31 e-mail : [email protected] Nom et prénom du responsable de l’équipe : Denis Furling Nombre de chercheurs et enseignants-chercheurs statutaires de l’équipe titulaires d’une HDR : 4 Nom et prénom du responsable du laboratoire : Butler-Browne Gillian Intitulé du laboratoire et N° d’unité : Centre de Recherche en Myologie, UMRS974 UPMC - INSERM / FRE 3617 CNRS / AIM Spécialité : Génétique Titre du projet de thèse : Heterogeneity of the Becker disease severity: involvement of intronic rearrangements, polymorphism and modulator genes? Résumé du projet de thèse (1 page maximum, en anglais) Background Mutations in DMD disrupting the reading frame prevent dystrophin production and result in Duchenne muscular dystrophy (DMD); in-frame internal deletions allow production of partly functional internally deleted dystrophin and result in the reputed less severe Becker muscular dystrophy (BMD). BMD45-55 Becker patients display in frame deletion of exons 45 to 55 in the DMD gene. While they all express a normal level of shortened dystrophin (Dys), they exhibit a phenotypic status ranging from asymptomatic to severe The aim of the project is the understanding of the phenotypic heterogeneity of BMD45-55 patients. Among the consequences of the 44 to 55 exon deletion, one is the alteration of the binding site of the neuronal nitric oxide synthase (nNOS) to the dystrophin. Indeed, this site is partly deleted in the truncateddystrophin expressed by the BMD45-55 patients. Interestingly, a study carried out on these patients showed a wide spectrum of nNOS protein expression and localization and its mislocalization was found to be correlated with increased severity of the clinical and histopathological muscle features (Gentil et al., 2012). However, the question of the difference in nNOS expression and location between BMD45-55 patients is not elucidated. Another consequence of the 45 to 55 exon deletion in the DMD gene is the result of breaks in introns 44 and 55 that leads to the creation of a neo-intron composed of the remaining part of intron 44 flanked by the remaining part of intron 55. The resulting sequence of the neo-intron depends on the breakpoint positions and could be different for each patient. Knowing that this new sequence could lead to the loss and/or the creation of important regulated sequences, it is an important interest to precisely characterize the breaking point sequence for each patient. A third investigation will track the expression of modifier genes. The data collected from a whole genome sequencing (WGS) will provide the opportunity to evaluate the polymorphism of genes that could act as modifier factors of the severity of the phenotype, such as genes related to lipid metabolism; anabolic and catabolic pathways and hypoxia. Taking into account the knowledge described above, the assumptions made for the understanding of the heterogeneity of BMD45-55 patients phenotypes are: 1/The interactions of Dystrophin and its partner nNOS would be differentially affected regarding the single- 1 Ecole Doctorale COMPLEXITE DU VIVANT – Fiche Projet CONCOURS nucleotide non-synonymous polymorphism (SNP) of the DMD and NOS1 genes. 2/The resulting neo-sequence, caused by the deletion of the 44 and 55 exons, contains known (and may yet unknown) sequences of non-coding RNA (ncRNA) and/or target sequences of ncRNA which could be modified by the deletion and differently from patient to patient. 3/The variability of the phenotype would be attributed to the expression of modifier factors that could impact on the pathophysiological process in affected muscles. To investigate these assumptions, we will carry out a whole genome sequencing (WGS) that will allow (i) establishing a double cartography of the Dys/nNOS binding site taking into account the polymorphism in DMD and NOS1 genes (ii) identifying breakpoints in introns 44 and 55 that could impact on the non-coding RNA identified in this zone (iii) identifying modulator genes that could be link to the worsening (or the improvement) of the phenotype of BMD patients. Thèses actuellement en cours dans l’équipe Nom et Prénom du doctorant Nom du directeur de thèse Année de 1ere inscription Financement pendant la thèse Le-Moing Anne-Gaëlle Servais Laurent 2012 CHU Amiens Damily De Dea Diniz Magdalena Matloka Furling Furling 2014 2015 UPMC DIM-Biothérapie Pauline Roy Ferry 2016 AIM *Trois publications récentes du directeur de thèse (du co-directeur ou du co-encadrant s’il y a lieu). Mettre en gras le nom du directeur de thèse. Longitudinal functional and NMR assessment of upper limbs in Duchenne muscular dystrophy. Hogrel JY, Wary C, Moraux A, Azzabou N, Decostre V, Ollivier G, Canal A, Lilien C, Ledoux I, Annoussamy M, Reguiba N, Gidaro T, Le Moing AG, Cardas R, Voit T, Carlier PG, Servais L. Neurology. 2016 Feb 17. Upper limb strength and function changes during a one-year follow-up in non-ambulant patients with Duchenne Muscular Dystrophy: an observational multicenter trial. Seferian AM, Moraux A, Annoussamy M, Canal A, Decostre V, Diebate O, Le Moing AG, Gidaro T, Deconinck N, Van Parys F, Vereecke W, Wittevrongel S, Mayer M, Maincent K, Desguerre I, Thémar-Noël C, Cuisset JM, Tiffreau V, Denis S, Jousten V, Quijano-Roy S, Voit T, Hogrel JY, Servais L. PLoS One. 2015 Feb 2;10(2):e0113999 Forelimb treatment in a large cohort of dystrophic dogs supports delivery of a recombinant AAV for exon skipping in Duchenne patients. Le Guiner C, Montus M, Servais L, Cherel Y, Francois V, Thibaud JL, Wary C, Matot B, Larcher T, Guigand L, Dutilleul M, Domenger C, Allais M, Beuvin M, Moraux A, Le Duff J, Devaux M, Jaulin N, Guilbaud M, Latournerie V, Veron P, Boutin S, Leborgne C, Desgue D, Deschamps JY, Moullec S, Fromes Y, Vulin A, Smith RH, Laroudie N, Barnay-Toutain F, Rivière C, Bucher S, Le TH, Delaunay N, Gasmi M, Kotin RM, Bonne G, Adjali O, Masurier C, Hogrel JY, Carlier P, Moullier P, Voit T. Mol Ther. 2014 Nov;22(11):1923-35. Docteurs encadrés par le directeur de thèse ayant soutenu après septembre 2008 et publications relatives à leur sujet de thèse. Mettre en gras le nom du directeur de thèse et celui du docteur. 2