{"id":1028,"date":"2026-06-16T13:55:57","date_gmt":"2026-06-16T13:55:57","guid":{"rendered":"https:\/\/www.lifescienceart.com\/?p=1028"},"modified":"2026-06-16T13:55:57","modified_gmt":"2026-06-16T13:55:57","slug":"tibetan-mastiffs-high-altitude-adaptation-adaptive-introgression","status":"publish","type":"post","link":"https:\/\/www.lifescienceart.com\/ro\/science\/zoology\/tibetan-mastiffs-high-altitude-adaptation-adaptive-introgression\/","title":{"rendered":"Mastifii tibetani: Secretele genetice ale supravie\u021buirii la \u00een\u0103l\u021bime"},"content":{"rendered":"<h2 class=\"wp-block-heading\">Cum au devenit Mastifii tibetani campioni de \u00een\u0103l\u021bime<\/h2>\n\n<h2 class=\"wp-block-heading\">Introgressie adaptiv\u0103: o scurt\u0103tur\u0103 genetic\u0103<\/h2>\n\n<p>Mastiful tibetan, cu p\u0103rul s\u0103u aspru \u0219i silueta impun\u0103toare, prosper\u0103 \u00een aerul sub\u021bire de oxigen de pe Platoul Tibetan, un mediu care reprezint\u0103 provoc\u0103ri pentru majoritatea animalelor. Dar cum au dob\u00e2ndit ace\u0219ti c\u00e2ini adapt\u0103rile necesare pentru a cuceri condi\u021bii at\u00e2t de extreme?<\/p>\n\n<p>Intr\u0103 \u00een scen\u0103 introgressia adaptiv\u0103, un fenomen \u00een care o specie ob\u021bine tr\u0103s\u0103turi avantajoase prin \u00eemperecherea cu o alt\u0103 specie, mai bine adaptat\u0103. Geneticianul Zhen Wang de la Institutele de \u0218tiin\u021be Biologice din Shanghai a suspectat c\u0103 mastifii tibetani au folosit aceast\u0103 scurt\u0103tur\u0103 evolutiv\u0103 prin \u00eemperecherea cu lupii gri, animale deja adaptate la altitudini mari.<\/p>\n\n<h2 class=\"wp-block-heading\">Dezv\u0103luirea secretelor genetice<\/h2>\n\n<p>Pentru a-\u0219i testa teoria, Wang a analizat genele mastifilor tibetani, c\u0103ut\u00e2nd variante genetice unice asociate cu succesul la \u00een\u0103l\u021bime. A examinat, de asemenea, genomurile a 49 de specii de canide care tr\u0103iesc \u00een apropierea Platoului Tibetan, inclusiv lupi, c\u00e2ini \u0219i \u0219acali.<\/p>\n\n<p>Echipa sa a descoperit dou\u0103 variante genice speciale \u00eemp\u0103rt\u0103\u0219ite exclusiv de mastifii tibetani \u0219i lupii gri: genele HBB \u0219i EPAS1. Aceste variante lucreaz\u0103 \u00een tandem pentru a spori eficien\u021ba oxigenului \u0219i pentru a preveni coagularea s\u00e2ngelui la altitudini mari.<\/p>\n\n<h2 class=\"wp-block-heading\">Rolul genelor HBB \u0219i EPAS1<\/h2>\n\n<p>Varianta genei HBB cre\u0219te capacitatea de transport a oxigenului a hemoglobinei, proteina din celulele ro\u0219ii care transport\u0103 oxigenul \u00een tot corpul. Aceast\u0103 adaptare permite mastifilor tibetani s\u0103 extrag\u0103 mai mult oxigen din aerul sub\u021bire de la altitudini \u00eenalte.<\/p>\n\n<p>Varianta genei EPAS1, pe de alt\u0103 parte, favorizeaz\u0103 cre\u0219terea vaselor de s\u00e2nge \u00een timp ce suprim\u0103 produc\u021bia general\u0103 de hemoglobin\u0103. Astfel, se evit\u0103 supra-producerea de hemoglobin\u0103 ca r\u0103spuns la nivelurile sc\u0103zute de oxigen, reduc\u00e2nd riscul de cheaguri de s\u00e2nge \u0219i accident vascular cerebral.<\/p>\n\n<h2 class=\"wp-block-heading\">O \u00eentors\u0103tur\u0103 surprinz\u0103toare \u00een istoria evolutiv\u0103<\/h2>\n\n<p>Studiul lui Wang sugereaz\u0103 c\u0103 remarcabilele adapt\u0103ri la \u00een\u0103l\u021bime ale mastifilor tibetani au fost dob\u00e2ndite relativ recent, \u00een urm\u0103 cu aproximativ 24\u202f000 de ani. Aceast\u0103 descoperire contrazice no\u021biunile tradi\u021bionale darwiniene despre \u201esupravie\u021buirea celui mai apt\u201d, demonstr\u00e2nd c\u0103 speciile pot beneficia uneori de \u00eemprumutarea genelor avantajoase de la alte specii.<\/p>\n\n<h2 class=\"wp-block-heading\">Implica\u021bii pentru alte specii<\/h2>\n\n<p>Studiul mastifilor tibetani \u0219i al introgressiei adaptive are implica\u021bii pentru \u00een\u021belegerea modului \u00een care alte specii se adapteaz\u0103 la medii extreme. Eviden\u021biaz\u0103 rolul schimbului genetic \u00een facilitarea schimb\u0103rilor evolutive rapide \u0219i sugereaz\u0103 c\u0103 \u00eemperecherea interspecii ar putea fi un factor cheie \u00een supravie\u021buirea \u0219i diversificarea vie\u021bii pe P\u0103m\u00e2nt.<\/p>\n\n<h2 class=\"wp-block-heading\">Informa\u021bii suplimentare<\/h2>\n\n<ul class=\"wp-block-list\">\n<li>Adapt\u0103rile mastifilor tibetani la \u00een\u0103l\u021bime includ eficien\u021b\u0103 sporit\u0103 a oxigenului, reducerea riscului de coagulare a s\u00e2ngelui \u0219i capacitatea de a rezista nivelurilor sc\u0103zute de oxigen.<\/li>\n<li>Introgressia adaptiv\u0103 a permis mastifilor tibetani s\u0103 dob\u00e2ndeasc\u0103 aceste adapt\u0103ri prin \u00eemperecherea cu lupii gri, deja bine adapta\u021bi la condi\u021biile dure ale Platoului Tibetan.<\/li>\n<li>Genele HBB \u0219i EPAS1 joac\u0103 roluri cruciale \u00een succesul mastifilor tibetani la \u00een\u0103l\u021bime, prin cre\u0219terea capacit\u0103\u021bii de transport a oxigenului \u0219i reglarea cre\u0219terii vaselor de s\u00e2nge.<\/li>\n<li>Studiul ofer\u0103 dovezi c\u0103 speciile pot beneficia de \u00eemperecherea interspecii, provoc\u00e2nd viziuni tradi\u021bionale despre competi\u021bia evolu\u021bionist\u0103.<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>Cum au devenit Mastifii tibetani campioni de \u00een\u0103l\u021bime Introgressie adaptiv\u0103: o scurt\u0103tur\u0103 genetic\u0103 Mastiful tibetan, cu p\u0103rul s\u0103u aspru \u0219i silueta impun\u0103toare, prosper\u0103 \u00een aerul sub\u021bire de oxigen de pe&hellip;<\/p>\n","protected":false},"author":1,"featured_media":25492,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[280],"tags":[2398,2399,136,188,2397,2396],"class_list":["post-1028","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-zoology","tag-adaptive-introgression","tag-canine-biology","tag-evolution","tag-genetics","tag-high-altitude-adaptation","tag-tibetan-mastiff"],"_links":{"self":[{"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/posts\/1028","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/comments?post=1028"}],"version-history":[{"count":2,"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/posts\/1028\/revisions"}],"predecessor-version":[{"id":25493,"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/posts\/1028\/revisions\/25493"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/media\/25492"}],"wp:attachment":[{"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/media?parent=1028"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/categories?post=1028"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lifescienceart.com\/ro\/wp-json\/wp\/v2\/tags?post=1028"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}