{"id":350381,"date":"2025-07-09T18:13:20","date_gmt":"2025-07-09T17:13:20","guid":{"rendered":"https:\/\/zakrasnejsivimperk.cz\/?p=350381"},"modified":"2025-07-09T18:14:41","modified_gmt":"2025-07-09T17:14:41","slug":"ceska-republika-cesti-vedci-odhaluji-zahadne-ztraty-nastroju-protivirove-imunity-u-ptaku","status":"publish","type":"post","link":"https:\/\/zakrasnejsivimperk.cz\/?p=350381","title":{"rendered":"\u010cESK\u00c1 REPUBLIKA: V\u011bdci odhaluj\u00ed ztr\u00e1ty n\u00e1stroj\u016f protivirov\u00e9 imunity u pt\u00e1k\u016f"},"content":{"rendered":"
\"\"
Ilustra\u010dn\u00ed foto: pixabay<\/figcaption><\/figure>\n

 <\/p>\n

Mezin\u00e1rodn\u00ed t\u00fdm veden\u00fd experty a expertkami z \u00dastavu molekul\u00e1rn\u00ed genetiky AV \u010cR ve spolupr\u00e1ci s Univerzitou Ludv\u00edka Maxmili\u00e1na v Mnichov\u011b identifikoval dva kl\u00ed\u010dov\u00e9 regula\u010dn\u00ed geny pta\u010d\u00ed imunity \u2013 IRF3 a IRF9, kter\u00e9 byly a\u017e dosud pova\u017eov\u00e1ny za chyb\u011bj\u00edc\u00ed v pta\u010d\u00edch genomech. Tyto poznatky m\u011bn\u00ed pohled na evoluci pta\u010d\u00ed imunity a otev\u00edraj\u00ed nov\u00e9 mo\u017enosti ve studiu ochrany proti virov\u00fdm infekc\u00edm nejen hospod\u00e1\u0159sk\u00fdch zv\u00ed\u0159at, ale i lid\u00ed. Pt\u00e1ci jsou toti\u017e p\u0159irozen\u00fdm rezervo\u00e1rem \u0159ady patogen\u016f, kter\u00e9 se p\u0159en\u00e1\u0161ej\u00ed na \u010dlov\u011bka.<\/h6>\n

\"\"Interferony hraj\u00ed z\u00e1sadn\u00ed roli v protivirov\u00e9 imunit\u011b. Slou\u017e\u00ed jako poplachov\u00e9 sign\u00e1ly upozor\u0148uj\u00edc\u00ed na virovou infekci. Bu\u0148ky je za\u010dnou produkovat ihned po za\u010d\u00e1tku infekce a d\u00e1vaj\u00ed t\u00edm sv\u00e9mu okol\u00ed najevo, \u017ee je pot\u0159eba zastavit \u0161\u00ed\u0159en\u00ed viru. Interferon se na povrchu bu\u0148ky nav\u00e1\u017ee na specifick\u00fd receptor a uvnit\u0159 bu\u0148ky spust\u00ed tzv. sign\u00e1ln\u00ed kask\u00e1du. Na jej\u00edm konci je vytvo\u0159en\u00ed molekul\u00e1rn\u00edho komplexu, kter\u00fd obsahuje kl\u00ed\u010dov\u00fd gen IRF9 (interferonov\u00fd regula\u010dn\u00ed faktor 9). Ten pak \u0159\u00edd\u00ed produkci mnoha bun\u011b\u010dn\u00fdch protivirov\u00fdch gen\u016f. IRF3 je zodpov\u011bdn\u00fd za produkci samotn\u00fdch interferon\u016f.<\/p>\n

\u201eZat\u00edmco role sav\u010d\u00edch IRF3 a IRF9 v imunitn\u00ed reakci je dob\u0159e pops\u00e1na, jejich pta\u010d\u00ed ekvivalenty z\u016fst\u00e1valy po desetilet\u00ed z\u00e1hadou. N\u00e1m se te\u010f poda\u0159ilo pta\u010d\u00ed IRF9 identifikovat a potvrdit jeho zapojen\u00ed v protivirov\u00e9 obran\u011b,\u201c<\/em> \u0159\u00edk\u00e1 Lenka Ungrov\u00e1 z \u00dastavu molekul\u00e1rn\u00ed genetiky AV \u010cR, prvn\u00ed autorka \u010dl\u00e1nku o regula\u010dn\u00edch genech, kter\u00fd nyn\u00ed zve\u0159ejnil presti\u017en\u00ed odborn\u00fd \u010dasopis BMC Biology<\/strong><\/a>. Genetick\u00e9 sekvence pta\u010d\u00edch IRF gen\u016f vykazovaly podle Lenky Ungrov\u00e9 zaj\u00edmav\u00e9 anom\u00e1ln\u00ed vlastnosti, kter\u00e9 velmi zt\u011b\u017euj\u00ed jejich identifikaci a z\u00e1rove\u0148 mohou souviset s pravou evolu\u010dn\u00ed ztr\u00e1tou genu.<\/p>\n

Ztraceno v evoluci<\/h6>\n

Pomoc\u00ed pokus\u016f na kachn\u00edch bu\u0148k\u00e1ch se uk\u00e1zalo, \u017ee bez genu IRF9 maj\u00ed po p\u0159id\u00e1n\u00ed interferonu velmi omezenou produkci protivirov\u00fdch gen\u016f. \u201eKdy\u017e jsme jim IRF9 znovu dodali, protivirov\u00e1 obrana se obnovila. To potvrzuje, \u017ee gen IRF9 je u pt\u00e1k\u016f funk\u010dn\u011b velmi d\u016fle\u017eit\u00fd \u2013 podobn\u011b jako u savc\u016f,\u201c<\/em> uv\u00e1d\u00ed v\u011bdkyn\u011b.<\/p>\n

Pomoc\u00ed modern\u00edch bioinformatick\u00fdch metod a anal\u00fdzy genetick\u00fdch datab\u00e1z\u00ed v\u011bdeck\u00e9 t\u00fdmy zjistily, \u017ee gen IRF3 se nach\u00e1z\u00ed pouze u pt\u00e1k\u016f ze skupiny b\u011b\u017ec\u016f, jako jsou p\u0161trosi, kivi nebo emu, gen IRF9 je p\u0159\u00edtomen u v\u011bt\u0161iny pt\u00e1k\u016f, ale chyb\u00ed t\u0159eba slepic\u00edm nebo ba\u017eant\u016fm.<\/p>\n

\u201eZ\u00e1hadou z\u016fst\u00e1v\u00e1, \u017ee u ku\u0159ete a dal\u0161\u00edch hrabav\u00fdch pt\u00e1k\u016f se n\u00e1m IRF9 identifikovat nepoda\u0159ilo a t\u00e9m\u011b\u0159 jist\u011b se v jejich evoluci ztratil. Nyn\u00ed se sna\u017e\u00edme zjistit, jak\u00fdm zp\u016fsobem byl tak d\u016fle\u017eit\u00fd protivirov\u00fd gen nahrazen,\u201c<\/em> zd\u016fraz\u0148uje Lenka Ungrov\u00e1.<\/p>\n

Mnoho vir\u016f, v\u010detn\u011b nap\u0159\u00edklad viru pta\u010d\u00ed ch\u0159ipky, r\u016fzn\u00fdmi mechanismy obrann\u00e9 interferonov\u00e9 dr\u00e1hy blokuje. D\u016fkladn\u011bj\u0161\u00ed pozn\u00e1n\u00ed a porovn\u00e1n\u00ed obrann\u00fdch siganalizac\u00ed mezi savci a pta\u010d\u00edmi druhy je nezbytn\u00fdm krokem ve v\u00fdvoji \u00fa\u010dinn\u00fdch antivirotik a vakc\u00edn.<\/p>\n

(tz-av\u010dr)<\/strong><\/p>\n

\n

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

  Mezin\u00e1rodn\u00ed <\/p>\n","protected":false},"author":2,"featured_media":350382,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"gallery","meta":{"footnotes":""},"categories":[19,174],"tags":[],"jetpack_featured_media_url":"https:\/\/zakrasnejsivimperk.cz\/wp-content\/uploads\/2025\/07\/03\/ptaci.jpg","_links":{"self":[{"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=\/wp\/v2\/posts\/350381"}],"collection":[{"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=350381"}],"version-history":[{"count":3,"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=\/wp\/v2\/posts\/350381\/revisions"}],"predecessor-version":[{"id":350923,"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=\/wp\/v2\/posts\/350381\/revisions\/350923"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=\/wp\/v2\/media\/350382"}],"wp:attachment":[{"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=350381"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=350381"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zakrasnejsivimperk.cz\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=350381"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}