{"id":3692,"date":"2014-09-05T14:03:44","date_gmt":"2014-09-05T13:03:44","guid":{"rendered":"https:\/\/www.egce.universite-paris-saclay.fr\/?p=3692"},"modified":"2014-09-05T14:03:44","modified_gmt":"2014-09-05T13:03:44","slug":"stage-de-m1-detection-de-sucres-a-longue-chaine-chez-drosophila-melanogaster","status":"publish","type":"post","link":"https:\/\/www.egce.universite-paris-saclay.fr\/?p=3692","title":{"rendered":"Stage de M1: D\u00e9tection de sucres \u00e0 longue cha\u00eene chez Drosophila melanogaster"},"content":{"rendered":"

Responsable du stage\u00a0:\u00a0<\/strong> Fr\u00e9d\u00e9ric Marion-Poll (01 69 82 37 56)\u00a0 et Jean-Luc Da Lage (01 69 82 37 27)<\/p>\n

frederic.marion-poll@universite-paris-saclay.fr<\/p>\n

jean-luc.da-lage@universite-paris-saclay.fr<\/p>\n

 <\/p>\n

Descriptif:<\/strong><\/p>\n

Chez les insectes, la d\u00e9tection des sucres commence \u00e0 \u00eatre bien comprise. Chez Drosophila melanogaster<\/em>, on a identifi\u00e9 9 r\u00e9cepteurs gustatifs: Gr5a<\/em>, Gr64a-f<\/em>, Gr61<\/em> et Gr43a<\/em>(1-5<\/em><\/a>).<\/em> Chacun d’eux conf\u00e8re aux neurones qui les expriment la sensibilit\u00e9 \u00e0 diff\u00e9rents types de sucres (Gr64a<\/em> est impliqu\u00e9 dans la d\u00e9tection du maltose, Gr5a<\/em> pour le tr\u00e9halose et Gr61a<\/em> pour le glyc\u00e9rol). Cependant, les sucres trouv\u00e9s dans l’alimentation sont souvent des polysaccharides. Par exemple, l\u2019amidon qui est un \u00e9l\u00e9ment important de l\u2019alimentation des drosophiles, n\u2019est pas d\u00e9tect\u00e9 directement car les mol\u00e9cules sont trop grosses pour interagir avec ces r\u00e9cepteurs.<\/p>\n

Le pouvoir sucrant de ces mol\u00e9cules i.e.<\/em> la capacit\u00e9 \u00e0 exciter les neurones gustatifs sensibles aux sucres, implique deux processus ind\u00e9pendants\u00a0:<\/p>\n

–\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 L\u2019interaction de ces mol\u00e9cules avec des sites r\u00e9cepteurs port\u00e9s par des prot\u00e9ines r\u00e9ceptrices ins\u00e9r\u00e9es dans la membrane des neurones gustatifs\u00a0; la taille des polym\u00e8res et leur solubilit\u00e9 repr\u00e9sente un frein \u00e0 leur d\u00e9tection.<\/p>\n

–\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 la pr\u00e9sence d\u2019enzymes dans le liquide pr\u00e9sent autour des neurones gustatifs, qui d\u00e9composent les polym\u00e8res de sucres en petites unit\u00e9s qui pourront interagir alors avec les r\u00e9cepteurs gustatifs. L\u2019implication de ces enzymes dans la d\u00e9tection de mol\u00e9cules sapides a \u00e9t\u00e9 tr\u00e8s peu \u00e9tudi\u00e9e jusqu\u2019ici (6-8<\/em><\/a>).<\/p>\n

Nous proposons d\u2019\u00e9tudier l\u2019influence de la longueur de cha\u00eene sur la d\u00e9tection des sucres, et en particulier de d\u00e9terminer la longueur de cha\u00eene au-del\u00e0 de laquelle le sucre n’est plus d\u00e9tect\u00e9. Nous suspectons que deux facteurs interviennent: 1) les r\u00e9cepteurs cit\u00e9s ci-dessus, 2) des enzymes pr\u00e9sentes dans les organes sensoriels ou le tube digestif, capables d’hydrolyser les polysaccharides en sucres plus petits. L’objectif du stage sera de rechercher les capacit\u00e9s de d\u00e9tection des mouches en fonction de la longueur de cha\u00eene et les g\u00e8nes impliqu\u00e9s dans la d\u00e9tection et l’hydrolyse des sucres au niveau sensoriel, par \u00e9lectrophysiologie (9<\/em><\/a>, <\/em>10<\/em><\/a>), et au niveau comportemental, par des exp\u00e9riences de choix (11<\/em><\/a>) ou de r\u00e9flexe d\u2019extension du proboscis (12<\/em><\/a>).<\/p>\n

R\u00e9f\u00e9rences dans le domaine :<\/strong><\/p>\n

 <\/p>\n

    \n
  1. E. G. Freeman, Z. Wisotsky, A. Dahanukar, Detection of sweet tastants by a conserved group of insect gustatory receptors. PNAS<\/em> 111<\/strong>, 1598 (Jan, 2014).<\/li>\n
  2. D. Mishra et al.<\/em>, The Molecular Basis of Sugar Sensing in Drosophila <\/em>Larvae. Curr. Biol.<\/em> 23<\/strong>, 1466 (Aug 5, 2013).<\/li>\n
  3. Z. Wisotsky, A. Medina, E. Freeman, A. Dahanukar, Evolutionary differences in food preference rely on Gr64e<\/em>, a receptor for glycerol. Nat. Neurosci.<\/em> 14<\/strong>, 1534 (Dec, 2011).<\/li>\n
  4. L. B. Kent, H. M. Robertson, Evolution of the sugar receptors in insects. BMC Evolutionary Biology<\/em> 9<\/strong>, 41 (Feb, 2009).<\/li>\n
  5. J. Slone, J. Daniels, H. Amrein, Sugar receptors in Drosophila<\/em>. Curr. Biol.<\/em> 17<\/strong>, 1809 (2007).<\/li>\n
  6. H. Wieczorek, G. Wolff, The labellar sugar receptor of Drosophila<\/em>. J. Comp. Physiol. A-Sens. Neural Behav. Physiol.<\/em> 164<\/strong>, 825 (1989).<\/li>\n
  7. M. Hara, Competitions of polysaccharides with sugars for the pyranose and the furanose site in the labellar sugar receptor cell of the blowfly, Phormia regina<\/em>. J. Insect Physiol.<\/em> 29<\/strong>, 113 (1983).<\/li>\n
  8. H. Wieczorek, R. Koppl, Reaction spectra of sugar receptors in different taste hairs of the fly. J. Comp. Physiol. A<\/em> 149<\/strong>, 207 (1982).<\/li>\n
  9. N. Meunier, J. F. Ferveur, F. Marion-Poll, Sex-specific non-pheromonal taste receptors in Drosophila<\/em>. Curr. Biol.<\/em> 10<\/strong>, 1583 (Dec 14-28, 2000).<\/li>\n
  10. M. Hiroi, F. Marion-Poll, T. Tanimura, Differentiated response to sugars among labellar chemosensilla in Drosophila<\/em>. Zool. Sci.<\/em> 19<\/strong>, 1009 (Sep, 2002).<\/li>\n
  11. M.-J. Sellier, P. Reeb, F. Marion-Poll, Consumption of bitter alkaloids in Drosophila melanogaster<\/em> in multiple-choice test conditions. Chem. Senses<\/em> 36<\/strong>, 323 (May, 2011).<\/li>\n
  12. P. Masek, K. Scott, Limited taste discrimination in Drosophila<\/em>. PNAS<\/em> 107<\/strong>, 14833 (Aug, 2010).<\/li>\n<\/ol>\n

     <\/p>\n","protected":false},"excerpt":{"rendered":"

    Responsable du stage\u00a0:\u00a0 Fr\u00e9d\u00e9ric Marion-Poll (01 69 82 37 56)\u00a0 et Jean-Luc Da Lage (01 69 82 37 27) frederic.marion-poll@universite-paris-saclay.fr jean-luc.da-lage@universite-paris-saclay.fr   Descriptif: Chez les insectes, la d\u00e9tection des sucres commence \u00e0 \u00eatre bien comprise. Chez Drosophila melanogaster, on a identifi\u00e9 9 r\u00e9cepteurs gustatifs: Gr5a, Gr64a-f, Gr61 et Gr43a(1-5). Chacun d’eux conf\u00e8re aux neurones qui […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"_themeisle_gutenberg_block_has_review":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[29,28,17],"tags":[],"class_list":["post-3692","post","type-post","status-publish","format-standard","hentry","category-master-i","category-stages","category-offres-demplois"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=\/wp\/v2\/posts\/3692","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3692"}],"version-history":[{"count":0,"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=\/wp\/v2\/posts\/3692\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3692"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3692"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3692"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}