{"id":10260,"date":"2010-02-01T09:53:30","date_gmt":"2010-02-01T07:53:30","guid":{"rendered":"http:\/\/109.232.216.219\/~bilimvegelecek\/?p=10260"},"modified":"2017-05-25T09:56:40","modified_gmt":"2017-05-25T06:56:40","slug":"40-milyon-yildir-viral-genom-tasiyoruz","status":"publish","type":"post","link":"https:\/\/bilimvegelecek.com.tr\/index.php\/2010\/02\/01\/40-milyon-yildir-viral-genom-tasiyoruz","title":{"rendered":"40 milyon y\u0131ld\u0131r viral genom ta\u015f\u0131yoruz!"},"content":{"rendered":"

\u0130nsan genomunun y\u00fczde 8 gibi b\u00fcy\u00fck bir k\u0131sm\u0131, evrimsel s\u00fcre\u00e7te omurgal\u0131 atalar\u0131ndan de\u011fil, viral canl\u0131lardan gelmektedir. Bu bilgi baz\u0131 insanlar\u0131 endi\u015felendirebilir; fakat bilinmelidir ki, belki de insan, d\u00fc\u015f\u00fcnd\u00fc\u011f\u00fc kadar \u201cinsan\u201d de\u011fildir!<\/p>\n

At ve koyun \u0131rklar\u0131nda \u00e7e\u015fitli hastal\u0131klara neden olan Borna vir\u00fcs\u00fc bir RNA vir\u00fcs\u00fcd\u00fcr ve en az 40 milyon y\u0131l \u00f6nce kendi genetik materyalini, insan atas\u0131n\u0131n genomuna yerle\u015ftirdi\u011fi bilinmektedir. Nature <\/em>dergisinin 7 Ocak 2010 say\u0131s\u0131nda yay\u0131nlanan makalede, retrovir\u00fcsler d\u0131\u015f\u0131nda di\u011fer RNA vir\u00fcslerinin de kendi genetik materyalini ba\u015fka bir canl\u0131n\u0131n genomuna yerle\u015ftirip, kararl\u0131 bir \u015fekilde aktar\u0131labildi\u011fi g\u00f6sterilmi\u015ftir.<\/p>\n

\u0130nsan genomu, evrim s\u00fcreci boyunca bir\u00e7ok bakteriyel, viral ya da di\u011fer organizmalar\u0131n genetik materyallerine maruz kalm\u0131\u015f, bu genetik materyaller, s\u00fcre\u00e7 i\u00e7erisinde insan genomuna eklenmi\u015f ve bu sayede bir\u00e7ok de\u011fi\u015fiklik ge\u00e7irerek bug\u00fcnk\u00fc halini alm\u0131\u015ft\u0131r. Hatta bir\u00e7ok temel fonksiyonlar (enfeksiyonlara kar\u015f\u0131 sava\u015f vb.) bu genetik entegrasyonlar ile kazan\u0131lm\u0131\u015ft\u0131r.\"\"<\/p>\n

Bu \u00e7al\u0131\u015fmada ara\u015ft\u0131rmac\u0131lar Borna vir\u00fcs\u00fcn\u00fcn N (nucleoprotein) geninin, insan genomuna en az 4 farkl\u0131 noktada eklendi\u011fini g\u00f6stermi\u015flerdir. Ayr\u0131ca di\u011fer memeli genomlar\u0131nda yap\u0131lan \u00e7al\u0131\u015fmalar ile de bu genin bir\u00e7ok kona\u011fa yerle\u015ferek vir\u00fcs\u00fcn hem kendisinin mutasyona u\u011frad\u0131\u011f\u0131, hem de kona\u011f\u0131 mutasyona u\u011fratt\u0131\u011f\u0131 ve bu sayede milyonlarca y\u0131ll\u0131k bir s\u00fcre\u00e7te bug\u00fcnk\u00fc formuna d\u00f6n\u00fc\u015ft\u00fc\u011f\u00fc g\u00f6sterilmi\u015ftir. \u00c7al\u0131\u015fmada g\u00f6sterilen Borna vir\u00fcs\u00fc fosil kay\u0131tlar\u0131, daha \u00f6nce retrovir\u00fcsler i\u00e7in g\u00f6sterilenlerle ayn\u0131 do\u011frultudad\u0131r ve bu da vir\u00fcslerin evriminin g\u00f6r\u00fcnd\u00fc\u011f\u00fcnden \u00e7ok daha farkl\u0131 oldu\u011funu d\u00fc\u015f\u00fcnd\u00fcrtmektedir.<\/p>\n

Osaka \u00dcniversitesi ara\u015ft\u0131rmac\u0131lar\u0131ndan Tomonaga Keizo ve arkada\u015flar\u0131n\u0131n yapt\u0131klar\u0131 bir ba\u015fka \u00e7al\u0131\u015fmada ise, insanda bulunan, EBLN-1 ve EBLN-2 olarak adland\u0131r\u0131lan iki genin, Borna vir\u00fcs\u00fc N genine \u00e7ok benzedi\u011fi ve bu genin endojen bir formu olup, vir\u00fcs\u00fcn atalar\u0131na ait molek\u00fcler fosilleri olabilece\u011fi g\u00f6sterilmi\u015ftir. Ayn\u0131 \u00e7al\u0131\u015fmada farkl\u0131 memeli gruplar\u0131 olarak, \u015fempanze, goril, orangutan, makak, fare, da\u011f tav\u015fan\u0131 ve sincaplar \u00fczerinde yap\u0131lan \u00e7al\u0131\u015fmalarda da bu iki genin \u00e7e\u015fitli formlar\u0131na rastlanm\u0131\u015ft\u0131r. Ayr\u0131ca bu genin genetik materyal olarak memeli genomuma eklenmesi olay\u0131n\u0131n en yak\u0131n\u0131 olarak, sincaplarda ve bundan yakla\u015f\u0131k 10 milyon y\u0131l \u00f6nce g\u00f6r\u00fcld\u00fc\u011f\u00fc rapor edilmi\u015ftir.<\/p>\n

Yap\u0131lan laboratuar \u00e7al\u0131\u015fmalar\u0131 ile de Borna vir\u00fcs\u00fcn genomunu yaln\u0131zca tarihte de\u011fil, halen insan, maymun s\u0131\u00e7an, k\u00f6pek ve farelerden al\u0131nan \u00e7e\u015fitli doku k\u00fclt\u00fcrlerinde, genoma kat\u0131lma g\u00f6sterdikleri g\u00f6zlemlenmi\u015ftir. G\u00fcn\u00fcm\u00fcz modern Borna vir\u00fcslerinin \u00f6zellikle \u00fcreme h\u00fccre hatlar\u0131nda genoma kat\u0131lma frekanslar\u0131n\u0131n y\u00fcksek oldu\u011fu ve bu sayede kal\u0131tsal entegrasyona neden oldu\u011fu g\u00f6sterilirken, bir di\u011fer h\u00fccre k\u00fclt\u00fcr\u00fc olan beyin h\u00fccrelerine de entegrasyon frekanslar\u0131n\u0131n y\u00fcksek olduklar\u0131 g\u00f6sterilmi\u015ftir. Bu sayede de \u00e7e\u015fitli n\u00f6rolojik hastal\u0131klar\u0131n ortaya \u00e7\u0131kmas\u0131na neden olduklar\u0131 d\u00fc\u015f\u00fcn\u00fclmektedir. Bu ba\u011flamda, \u015fizofreni gibi baz\u0131 psikiyatrik hastal\u0131klar ile bu vir\u00fcs ya da onun geninin entegrasyonu sonucu ortaya \u00e7\u0131kan N geni aras\u0131nda ba\u011flant\u0131lar ara\u015ft\u0131r\u0131lmaktad\u0131r.<\/p>\n

 <\/p>\n

KAYNAKLAR<\/strong><\/p>\n

1) Feschotte, C. 2010. Bornavirus enters the genome.<\/em> Nature 463(Jan. 7): 39-40<\/p>\n

2) http:\/\/www.sciencenews.org\/view\/generic\/id\/52925\/title\/Bornavirus_genes_found_in_human_DNA, 20 Ocak 2010.<\/p>\n

3) Tomonaga K ve ark, 2000, Isolation of borna vir\u00fcs from human brain tissue. <\/em>Journal of Virology, May 2000, p. 4601-4611, Vol. 74, No. 10<\/p>\n","protected":false},"excerpt":{"rendered":"

\u0130nsan genomunun y\u00fczde 8 gibi b\u00fcy\u00fck bir k\u0131sm\u0131, evrimsel s\u00fcre\u00e7te omurgal\u0131 atalar\u0131ndan de\u011fil, viral canl\u0131lardan gelmektedir. Bu bilgi baz\u0131 insanlar\u0131 endi\u015felendirebilir; fakat bilinmelidir ki, belki de insan, d\u00fc\u015f\u00fcnd\u00fc\u011f\u00fc kadar \u201cinsan\u201d de\u011fildir! At ve koyun \u0131rklar\u0131nda \u00e7e\u015fitli hastal\u0131klara neden olan Borna vir\u00fcs\u00fc bir RNA vir\u00fcs\u00fcd\u00fcr ve en az 40 milyon y\u0131l \u00f6nce kendi genetik materyalini, insan […]<\/p>\n","protected":false},"author":206,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[109,19,231],"tags":[],"class_list":["post-10260","post","type-post","status-publish","format-standard","hentry","category-72-sayi","category-bilim-gundemi","category-molekuler-biyoloji-ve-genetik"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t