{"id":16987,"date":"2023-09-29T09:40:49","date_gmt":"2023-09-29T07:40:49","guid":{"rendered":"https:\/\/www.egce.universite-paris-saclay.fr\/?p=16987"},"modified":"2023-09-29T09:40:50","modified_gmt":"2023-09-29T07:40:50","slug":"sujet-de-stage-m1-2024-2","status":"publish","type":"post","link":"https:\/\/www.egce.universite-paris-saclay.fr\/?p=16987&lang=en","title":{"rendered":"Sujet de stage M1 2024"},"content":{"rendered":"\n<p>Caract\u00e9risation enzymologique des trois alpha-amylases de la Sesamie du ma\u00efs, <em>Sesamia nonagrioides<\/em><\/p>\n\n\n\n<p>La s\u00e9samie du ma\u00efs est un papillon de la familles des Noctuidae, originaire d\u2019Afrique subsaharienne. Dans sa r\u00e9gion d\u2019origine, la chenille vit et se nourrit sur des plantes sauvages de roseaux des familles Typhac\u00e9es et Cyp\u00e9rac\u00e9es. En Europe m\u00e9diterran\u00e9enne, l\u2019esp\u00e8ce est pr\u00e9sente depuis plus de 100 000 ans, mais s\u2019est adapt\u00e9e, depuis qu\u2019il est cultiv\u00e9 en Europe, au ma\u00efs, qui constitue sa plante h\u00f4te principale. Cette chenille est devenue un ravageur pr\u00e9occupant, et des recherches sont en cours afin de d\u00e9velopper des moyens de lutte biologique.<\/p>\n\n\n\n<p>Il a \u00e9t\u00e9 montr\u00e9 dans notre laboratoire qu\u2019une gu\u00eape parasito\u00efde sp\u00e9cifique de la s\u00e9samie du ma\u00efs reconna\u00eet son h\u00f4te \u00e0 courte distance via des stimulus gustatifs impliquant l\u2019alpha-amylase produite par la chenille, et r\u00e9gurgit\u00e9e lorsqu\u2019elle fore les tiges de ma\u00efs. Le g\u00e9nome de <em>Sesamia nonagrioides<\/em> a \u00e9t\u00e9 s\u00e9quenc\u00e9 au laboratoire (Muller et al 2021). On y trouve trois copies du g\u00e8ne de l\u2019alpha-amylase, dont deux sont tr\u00e8s proches en s\u00e9quence et la troisi\u00e8me nettement plus divergente.<\/p>\n\n\n\n<p>Depuis longtemps, on se pose la question de l\u2019int\u00e9r\u00eat adaptatif de poss\u00e9der plusieurs copies du g\u00e8ne <em>Amy<\/em>. Ce g\u00e8ne est en effet tr\u00e8s souvent sous forme de famille multig\u00e9nique dans la plupart des esp\u00e8ces d\u2019insectes, mais aussi d\u2019autres animaux, plantes, microbes\u2026<\/p>\n\n\n\n<p>Lors de notre \u00e9tude r\u00e9cente sur l\u2019attractivit\u00e9 de la gu\u00eape parasito\u00efde (stage de M2, 2023), nous avons pu produire <em>in vitro<\/em>, en syst\u00e8me levure,&nbsp; les trois amylases de la chenille.<\/p>\n\n\n\n<p>C\u2019est une occasion unique d\u2019\u00e9tudier les diff\u00e9rences enzymologiques qui peuvent exister entre elles, ce qui pourrait nous aider \u00e0 comprendre l\u2019int\u00e9r\u00eat adaptatif de leur existence et de leurs diff\u00e9rences&nbsp;: pH et temp\u00e9ratures optimum, affinit\u00e9 pour le substrat, activit\u00e9 sur diff\u00e9rents substrats, param\u00e8tres cin\u00e9tiques, sensibilit\u00e9 \u00e0 des inhibiteurs\u2026<\/p>\n\n\n\n<p>Le stage consistera \u00e0 \u00e9valuer ces caract\u00e9ristiques enzymatiques. Il sera sans doute aussi n\u00e9cessaire de produire et purifier l\u2019une ou l\u2019autre de ces amylase en levure.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Caract\u00e9risation enzymologique des trois alpha-amylases de la Sesamie du ma\u00efs, Sesamia nonagrioides La s\u00e9samie du ma\u00efs est un papillon de la familles des Noctuidae, originaire d\u2019Afrique subsaharienne. Dans sa r\u00e9gion d\u2019origine, la chenille vit et se nourrit sur des plantes sauvages de roseaux des familles Typhac\u00e9es et Cyp\u00e9rac\u00e9es. En Europe m\u00e9diterran\u00e9enne, l\u2019esp\u00e8ce est pr\u00e9sente depuis [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","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":[7],"tags":[],"class_list":["post-16987","post","type-post","status-publish","format-standard","hentry","category-non-classe-en"],"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\/16987","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=16987"}],"version-history":[{"count":1,"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=\/wp\/v2\/posts\/16987\/revisions"}],"predecessor-version":[{"id":16988,"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=\/wp\/v2\/posts\/16987\/revisions\/16988"}],"wp:attachment":[{"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=16987"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=16987"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.egce.universite-paris-saclay.fr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=16987"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}