{"id":678122,"date":"2026-02-22T06:26:03","date_gmt":"2026-02-22T06:26:03","guid":{"rendered":"https:\/\/microscopemedia.com\/?p=678122"},"modified":"2026-02-22T06:26:03","modified_gmt":"2026-02-22T06:26:03","slug":"o-specie-noua-de-virus-gigant-ne-arata-cum-a-aparut-viata-avansata-pe-pamant","status":"publish","type":"post","link":"https:\/\/microscopemedia.com\/?p=678122","title":{"rendered":"O specie nou\u0103 de virus gigant ne arat\u0103 cum a ap\u0103rut via\u021ba avansat\u0103 pe P\u0103m\u00e2nt"},"content":{"rendered":"
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Spre deosebire de celulele vii, virusurile sunt alc\u0103tuite doar din material genetic \u0219i nu pot produce proteine pe cont propriu, potrivit ScienceDaily<\/a>.<\/p>\n

Deoarece proteinele sunt esen\u021biale pentru activitatea celular\u0103 \u0219i supravie\u021buire, virusurile depind \u00een totalitate de celulele gazd\u0103 pentru a func\u021biona.<\/p>\n

De zeci de ani, oamenii de \u0219tiin\u021b\u0103 au \u00eencercat s\u0103 \u00een\u021beleag\u0103 de unde provin virusurile, cum au evoluat \u0219i cum se \u00eencadreaz\u0103 \u00een arborele vie\u021bii.<\/p>\n

Profesorul Masaharu Takemura de la Facultatea de \u0218tiin\u021be a Universit\u0103\u021bii de \u0218tiin\u021be din Tokyo (TUS), Japonia, a fost o figur\u0103 de frunte \u00een acest efort.<\/p>\n

\u00cen 2001, el \u0219i dr. Philip Bell de la Departamentul de \u0218tiin\u021be Biologice al Universit\u0103\u021bii Macquarie din Sydney au propus \u00een mod independent teoria originii virusului nuclear celular, cunoscut\u0103 \u0219i sub numele de eucariogenez\u0103 viral\u0103 (termen inventat de dr. Bell).<\/p>\n

Aceast\u0103 ipotez\u0103 sugereaz\u0103 c\u0103 nucleul celulelor eucariote (celule al c\u0103ror nucleu este \u00eenconjurat de o membran\u0103) ar putea proveni dintr-un virus ADN mare, cum ar fi poxvirusul, care a infectat un str\u0103mo\u0219 arheu (microorganisme unicelulare). \u00cen loc s\u0103-\u0219i distrug\u0103 gazda, virusul ar fi putut s\u0103 se stabileasc\u0103 \u00een mod stabil \u00een citoplasm\u0103.<\/p>\n

De-a lungul timpului, este probabil c\u0103 a absorbit gene importante din celula gazd\u0103 \u0219i s-a transformat treptat \u00een ceea ce recunoa\u0219tem ast\u0103zi ca nucleul celulelor eucariote.<\/p>\n

Dac\u0103 este corect\u0103, aceast\u0103 teorie \u00eenseamn\u0103 c\u0103 virusurile ar fi putut juca un rol central \u00een apari\u021bia vie\u021bii complexe.<\/p>\n

Sus\u021binerea acestei idei a crescut \u00een 2003 odat\u0103 cu descoperirea viru\u0219ilor ADN gigantici.<\/p>\n

C\u00e2nd ace\u0219ti viru\u0219i infecteaz\u0103 celulele, ei creeaz\u0103 structuri cunoscute sub numele de fabrici de viru\u0219i \u00een interiorul gazdelor lor.<\/p>\n

\u00cen unele cazuri, aceste fabrici sunt \u00eenconjurate de membrane \u0219i servesc ca locuri pentru replicarea ADN-ului, asem\u0103n\u00e2ndu-se cu o versiune primitiv\u0103 a nucleului celular.<\/p>\n

Aceast\u0103 similitudine a \u00eent\u0103rit leg\u0103tura evolutiv\u0103 propus\u0103 \u00eentre viru\u0219i \u0219i celulele complexe.<\/p>\n

\u00cen ultimii ani, cercet\u0103torii au identificat al\u021bi viru\u0219i ADN gigantici. Printre ace\u0219tia se num\u0103r\u0103 membrii familiei Mamonoviridae, care infecteaz\u0103 acanthamoeba (un tip de amoeb\u0103, care este un microorganism unicelular), \u0219i clandestinovirus, un virus str\u00e2ns \u00eenrudit care infecteaz\u0103 vermamoeba (un alt tip de amoeb\u0103 dintr-o familie diferit\u0103).<\/p>\n

Descoperirea virusului Ushiku<\/h2>\n

\u00centr-un nou studiu publicat \u00een Journal of Virology, prof. Takemura \u0219i colaboratorii s\u0103i de la Institutul Na\u021bional de \u0218tiin\u021be Naturale (NINS) din Japonia descriu un alt virus ADN gigant care infecteaz\u0103 amoeba. Virusul, numit ushikuvirus dup\u0103 lacul Ushiku din prefectura Ibaraki, Japonia, unde a fost izolat, adaug\u0103 dovezi suplimentare care sus\u021bin ipoteza originii virusului nuclear.<\/p>\n

Echipa de cercetare a inclus studen\u021bi la masterat la Facultatea de \u0218tiin\u021be, TUS, \u00eempreun\u0103 cu dr. Raymond Burton-Smith \u0219i profesorul Kazuyoshi Murata de la NINS.<\/p>\n

\u201eViru\u0219ii gigantici pot fi considera\u021bi o comoar\u0103 a c\u0103rei lume nu a fost \u00eenc\u0103 pe deplin \u00een\u021beleas\u0103. Una dintre posibilit\u0103\u021bile viitoare ale acestei cercet\u0103ri este de a oferi umanit\u0103\u021bii o nou\u0103 perspectiv\u0103 care leag\u0103 lumea organismelor vii de lumea viru\u0219ilor\u201d, spune prof. Takemura.<\/p>\n

Structur\u0103 unic\u0103 \u0219i strategie de infectare<\/h3>\n

Viru\u0219ii gigantici sunt r\u0103sp\u00e2ndi\u021bi \u00een natur\u0103, dar izolarea lor este dificil\u0103. De asemenea, sunt remarcabil de dive\u0219si, ceea ce face ca fiecare nou\u0103 descoperire s\u0103 fie semnificativ\u0103. Ushikuvirus infecteaz\u0103 vermamoeba, similar cu clandestinovirus, \u0219i are similitudini structurale cu familia Mamonoviridae, \u00een special cu Medusavirus. Medusavirus este cunoscut pentru forma sa icosaedric\u0103 \u0219i numeroasele spicule scurte care acoper\u0103 suprafa\u021ba capsidului.<\/p>\n

Cu toate acestea, ushikuvirus prezint\u0103 \u0219i diferen\u021be importante. Acesta declan\u0219eaz\u0103 un efect citopatic distinct, care determin\u0103 cre\u0219terea neobi\u0219nuit\u0103 a celulelor vermamoeba infectate. Suprafa\u021ba capsidei sale con\u021bine multiple structuri de proeminen\u021be acoperite cu capace unice, unele cu extensii filamentoase care nu se reg\u0103sesc la medusavirusuri.<\/p>\n

O alt\u0103 diferen\u021b\u0103 cheie const\u0103 \u00een modul \u00een care virusul se replic\u0103. Medusavirusurile \u0219i clandestinovirusul se reproduc \u00een interiorul unui nucleu gazd\u0103 intact. \u00cen schimb, ushikuvirusul descompune membrana nuclear\u0103 \u00een timpul replic\u0103rii pentru a produce noi particule virale. Acest comportament sugereaz\u0103 o posibil\u0103 leg\u0103tur\u0103 evolutiv\u0103 \u00eentre virusurile din familia Mamonoviridae, care utilizeaz\u0103 nucleul intact ca fabric\u0103 viral\u0103, \u0219i virusurile gigantice, precum pandoravirusul, care perturb\u0103 membrana nuclear\u0103. Oamenii de \u0219tiin\u021b\u0103 cred c\u0103 aceste diferen\u021be pot reflecta adapt\u0103ri la diferite gazde de-a lungul timpului.<\/p>\n

Indicii privind evolu\u021bia eucariotelor<\/h4>\n

Prin examinarea acestor varia\u021bii structurale \u0219i func\u021bionale, cercet\u0103torii ob\u021bin informa\u021bii despre modul \u00een care virusurile gigantice s-au diversificat \u0219i despre modul \u00een care interac\u021biunile lor cu celulele gazd\u0103 ar fi putut influen\u021ba evolu\u021bia vie\u021bii eucariote complexe.<\/p>\n

\u201eDescoperirea unui nou virus din familia Mamonoviridae, \u201eushikuvirus\u201d, care are o gazd\u0103 diferit\u0103, se a\u0219teapt\u0103 s\u0103 sporeasc\u0103 cuno\u0219tin\u021bele \u0219i s\u0103 stimuleze discu\u021biile privind evolu\u021bia \u0219i filogenia familiei Mamonoviridae. Ca urmare, se crede c\u0103 vom putea s\u0103 ne apropiem de misterele evolu\u021biei organismelor eucariote \u0219i de misterele virusurilor gigantice\u201d, spune prof. Takemura.<\/p>\n

Implica\u021bii poten\u021biale pentru s\u0103n\u0103tate<\/h5>\n

Descoperirea virusurilor gigantice care infecteaz\u0103 amoebele poate avea \u0219i o valoare practic\u0103. Anumite specii de Acanthamoeba pot provoca boli grave, inclusiv encefalita amoebic\u0103. O \u00een\u021belegere mai profund\u0103 a modului \u00een care virusurile gigantice infecteaz\u0103 \u0219i distrug amoebele ar putea ajuta \u00een cele din urm\u0103 cercet\u0103torii s\u0103 dezvolte noi abord\u0103ri pentru prevenirea sau tratarea acestor infec\u021bii.<\/p>\n","protected":false},"excerpt":{"rendered":"

Spre deosebire de celulele vii, virusurile sunt alc\u0103tuite doar din material genetic \u0219i nu pot produce proteine pe cont propriu, potrivit ScienceDaily. Deoarece proteinele sunt esen\u021biale pentru activitatea celular\u0103 \u0219i … Read More<\/a><\/p>\n","protected":false},"author":1,"featured_media":678123,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"Default","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/microscopemedia.com\/index.php?rest_route=\/wp\/v2\/posts\/678122"}],"collection":[{"href":"https:\/\/microscopemedia.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/microscopemedia.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/microscopemedia.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/microscopemedia.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=678122"}],"version-history":[{"count":0,"href":"https:\/\/microscopemedia.com\/index.php?rest_route=\/wp\/v2\/posts\/678122\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/microscopemedia.com\/index.php?rest_route=\/wp\/v2\/media\/678123"}],"wp:attachment":[{"href":"https:\/\/microscopemedia.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=678122"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/microscopemedia.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=678122"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/microscopemedia.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=678122"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}