{"id":7736,"date":"2017-11-21T00:00:00","date_gmt":"2017-11-20T23:00:00","guid":{"rendered":"https:\/\/idibell.cat\/blog\/2017\/11\/21\/les-isoformes-de-la-proteina-hp1-regulen-diferencialment-lorganitzacio-i-estructura-de-lheterocromatina\/"},"modified":"2020-05-13T19:46:39","modified_gmt":"2020-05-13T17:46:39","slug":"les-isoformes-de-la-proteina-hp1-regulen-diferencialment-lorganitzacio-i-estructura-de-lheterocromatina","status":"publish","type":"post","link":"https:\/\/idibell.cat\/2017\/11\/les-isoformes-de-la-proteina-hp1-regulen-diferencialment-lorganitzacio-i-estructura-de-lheterocromatina\/","title":{"rendered":"Les isoformes de la prote\u00efna HP1 regulen diferencialment l\u2019organitzaci\u00f3 i estructura de l\u2019heterocromatina"},"content":{"rendered":"<p>Investigadors del Programa d\u2019Epigen\u00e8tica i Biologia del c\u00e0ncer de l\u2019Institut d\u2019Investigaci\u00f3 Biom\u00e8dica de Bellvitge (IDIBELL), liderats pel Dr. \u00c0lex Vaquero, han aprofundit en el rol de les prote\u00efnes HP1 en relaci\u00f3 a l\u2019estructura de la cromatina i l\u2019estabilitat del genoma, distingint efectes diferenciats en base a la pres\u00e8ncia de les diferents variants d\u2019aquesta prote\u00efna. El treball, publicat a <em>Cell Reports<\/em>, compta amb la col\u00b7laboraci\u00f3 d\u2019altres grups de recerca d\u2019Europa i Estats Units.<\/p>\n<p> El nostre material gen\u00e8tic s\u2019organitza dins del nucli cel\u00b7lular en forma de cromatina, una estructura constitu\u00efda principalment per mol\u00e8cules d&#8217;ADN associades a histones i altres prote\u00efnes. La cromatina es troba en dues formes clarament diferenciables quan la c\u00e8l\u00b7lula no s\u2019est\u00e0 dividint: l&#8217;eucromatina (menys condensada) i l&#8217;heterocromatina (m\u00e9s condensada). La prote\u00efna de l\u2019heterocromatina 1 (HP1) \u00e9s un component estructural de l\u2019heterocromatina que existeix en tres variants o isoformes diferents: HP1\u03b1, HP1\u03b2 i HP1\u03b3. Gran part de l\u2019activitat d\u2019aquestes isoformes sembla ser redundant, \u00e9s a dir, equivalent independentment de la variant. <\/p>\n<p> En un treball anterior publicat a principis d\u2019any per la revista <em>Epigenetics<\/em>, l\u2019equip del Dr. Vaquero va demostrar que a difer\u00e8ncia del que es pensava, sota condicions d\u2019estr\u00e8s oxidatiu (involucrat en moltes malalties, com c\u00e0ncer, el Parkinson i l&#8217;Alzheimer, aix\u00ed com en l&#8217;envelliment), les tres variants d\u2019HP1 juguen papers diferents al manteniment de l\u2019estabilitat i l\u2019establiment dels diferents nivells de compactaci\u00f3 de la cromatina. Espec\u00edficament, les tres variants estableixen relacions funcionals diferencials amb la metiltransferasa Suv39h1, enzim clau al control epigen\u00e8tic del genoma. <\/p>\n<p> En aquest nou estudi publicat a <em>Cell Reports<\/em>, s\u2019aprofundeix en el paper regulatori d\u2019HP1\u03b1, HP1\u03b2 i HP1\u03b3 en relaci\u00f3 a l\u2019heterocromatina peric\u00e8ntrica, \u00e9s a dir, la que delimita la zona del centr\u00f2mer o punt d\u2019uni\u00f3 entre les crom\u00e0tides germanes en un cromosoma. Aquestes regions juguen un paper estructural clau al genoma, i la seva alteraci\u00f3 est\u00e0 associada a inestabilitat gen\u00f2mica, aberracions cromos\u00f2miques i malalties humanes com el c\u00e0ncer. En una s\u00e8rie d\u2019experiments amb fibroblasts embrionaris de ratol\u00ed (MEFs), els investigadors demostren que la p\u00e8rdua espec\u00edfica d\u2019HP1\u03b1 d\u00f3na lloc a una major pres\u00e8ncia de les marques epigen\u00e8tiques H4K20me3 i H3K27me3, <\/p>\n<p>directament vinculades a la hipercompactaci\u00f3 de la cromatina; per contra, la p\u00e8rdua d\u2019HP1\u03b2 d\u00f3na lloc a un augment de CTCF a la zona d\u2019estudi, un factor de transcripci\u00f3 clau en la regulaci\u00f3 de l\u2019arquitectura de la cromatina. <\/p>\n<p> Aix\u00ed doncs, en base a la interacci\u00f3 secund\u00e0ria que generen amb d\u2019altres prote\u00efnes i enzims, les diferents prote\u00efnes HP1 podrien jugar un paper diferencial en l\u2019organitzaci\u00f3 dels dominis cromat\u00ednics. En paraules del Dr. Vaquero, \u201cHP1\u03b1 mantindria, conjuntament amb CTCF, l\u2019estructura interna de l\u2019heterocromatina perif\u00e8rica mitjan\u00e7ant el control de la distribuci\u00f3 de H4K20me3 i H3K27me3. Aquesta troballa amplia el nostre coneixement actual de l\u2019organitzaci\u00f3 del genoma aportant una nova perspectiva pel que fa al paper de les isoformes d\u2019HP1 i la seva relaci\u00f3 funcional amb l\u2019estructura de l\u2019heterocromatina i la seva estabilitat\u201d. Tenint en compte que les alteracions en l\u2019heterocromatina peric\u00e8ntrica s\u2019han relacionat amb defectes en el cicle cel\u00b7lular, danys en l\u2019ADN, aberracions cromos\u00f2miques, mort cel\u00b7lular, c\u00e0ncer i envelliment, ambd\u00f3s estudis obren cam\u00ed des de la recerca b\u00e0sica cap a una millor comprensi\u00f3 d\u2019aquests processos vinculats a nombroses malalties.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Investigadors del Programa d\u2019Epigen\u00e8tica i Biologia del c\u00e0ncer de l\u2019Institut d\u2019Investigaci\u00f3 Biom\u00e8dica de Bellvitge (IDIBELL), liderats pel Dr. \u00c0lex Vaquero, han aprofundit en el rol de les prote\u00efnes HP1 en relaci\u00f3 a l\u2019estructura de la cromatina i l\u2019estabilitat del genoma, distingint efectes diferenciats en base a la pres\u00e8ncia de les diferents variants d\u2019aquesta prote\u00efna. El [&hellip;]<\/p>\n","protected":false},"author":6,"featured_media":7737,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"no-sidebar","site-content-layout":"page-builder","ast-site-content-layout":"","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":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"default","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":"","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":""}},"footnotes":""},"categories":[1],"tags":[],"class_list":["post-7736","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-sin-categorizar"],"publishpress_future_action":{"enabled":false,"date":"2024-12-30 06:40:28","action":"change-status","newStatus":"draft","terms":[],"taxonomy":"category"},"publishpress_future_workflow_manual_trigger":{"enabledWorkflows":[]},"_links":{"self":[{"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/posts\/7736","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/comments?post=7736"}],"version-history":[{"count":0,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/posts\/7736\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/media\/7737"}],"wp:attachment":[{"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/media?parent=7736"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/categories?post=7736"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/tags?post=7736"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}