{"id":10926,"date":"2010-04-01T15:39:18","date_gmt":"2010-04-01T12:39:18","guid":{"rendered":"http:\/\/109.232.216.219\/~bilimvegelecek\/?p=10926"},"modified":"2017-05-31T15:42:23","modified_gmt":"2017-05-31T12:42:23","slug":"seni-benden-farkli-yapan-ne","status":"publish","type":"post","link":"https:\/\/bilimvegelecek.com.tr\/index.php\/2010\/04\/01\/seni-benden-farkli-yapan-ne","title":{"rendered":"Seni benden farkl\u0131 yapan ne?"},"content":{"rendered":"

Ara\u015ft\u0131rmac\u0131lar uzun bir s\u00fcredir bir insan\u0131n di\u011ferinden fark\u0131n\u0131n sadece genlerden kaynakland\u0131\u011f\u0131n\u0131 d\u00fc\u015f\u00fcn\u00fcyorlard\u0131. Genler, h\u00fccrenin i\u015flerini yapabilmesi i\u00e7in gerekli olan proteinlerin yap\u0131m\u0131 i\u00e7in gerekli komutlar\u0131 ta\u015f\u0131rlar. T\u00fcm insanlar aras\u0131ndaki gen \u00e7e\u015fitlili\u011fi yakla\u015f\u0131k y\u00fczde 0,025\u2019dir. Bilim insanlar\u0131 uzun y\u0131llard\u0131r bu ufak farkl\u0131l\u0131\u011fa bakarak kim ve ne oldu\u011fumuzu anlamaya \u00e7al\u0131\u015f\u0131yorlar. Di\u011fer taraftan genomumuzda her hangi bir protein sentezi yapmayan gen b\u00f6lgeleri DNA\u2019m\u0131z\u0131n y\u00fczde 98\u2019ini kaplar ve y\u00fczde 1-4 aras\u0131nda \u00e7e\u015fitlilik g\u00f6sterir. Fakat bug\u00fcne kadar, bu b\u00f6lgelerin beni ben, seni de sen yapan \u00f6zel kar\u0131\u015f\u0131ma nas\u0131l bir katk\u0131da bulundu\u011fu hakk\u0131nda bilim insanlar\u0131 \u00e7ok az bilgiye sahipti.\"\"<\/p>\n

Standford \u00dcniversitesi\u2019nde yap\u0131lan bir ara\u015ft\u0131rmada bireyler aras\u0131nda DNA dizisindeki tek ve \u00f6zel de\u011fi\u015fikli\u011fin, gen ifadesinin kontrol\u00fcn\u00fc yapan ve \u201ctranskripsiyon fakt\u00f6r\u201d olarak isimlendirilen kontrol proteinini etkiledi\u011fi bulunmu\u015f. Transkrisyon fakt\u00f6r\u00fcn\u00fcn farkl\u0131 ba\u011flanma etkisi gen ifadesinde de\u011fi\u015fikli\u011fe sebep olur ve bu durum bireyler aras\u0131ndaki bir\u00e7ok farkl\u0131l\u0131\u011f\u0131 a\u00e7\u0131klar. Transkripsiyon fakt\u00f6r\u00fc DNA\u2019ya ba\u011flan\u0131r ve RNA polimeraz II\u2019nin ve DNA\u2019n\u0131n RNA\u2019ya ifadesini etkileyerek gen ifadesinde azalma veya art\u0131\u015f sa\u011flayan bir hareket sergiler.<\/p>\n

Yap\u0131lan \u00e7al\u0131\u015fmada 10 ki\u015fide ve 1 \u015fempanzede iki farkl\u0131 transkripsiyon fakt\u00f6r\u00fcn\u00fcn ba\u011flanma paternleri kar\u015f\u0131la\u015ft\u0131r\u0131lm\u0131\u015f. 10 ki\u015fi i\u00e7inden herhangi 2 ki\u015fi aras\u0131nda y\u00fczde 25 RNA polimeraz II, y\u00fczde 7,5 NF-kappa B ba\u011flanma b\u00f6lgelerinde farkl\u0131l\u0131k g\u00f6sterilmi\u015f. RNA polimeraz II t\u00fcm h\u00fccrelerde aktif olan DNA dizisinin RNA\u2019ya ifadesini sa\u011flayan bir proteindir ve aktivitesi DNA b\u00f6lgesine ba\u011flanan transkripsiyon fakt\u00f6r\u00fcne ba\u011fl\u0131d\u0131r. NF-kappa B ise bir transkripsiyon fakt\u00f6r\u00fcd\u00fcr ve stresli ko\u015fullarda aktifle\u015fir. \u00d6zellikle enfeksiyon durumunda ba\u011f\u0131\u015f\u0131kl\u0131k sisteminin cevap olu\u015fturmas\u0131nda \u00f6nemli bir rol oynar. \u00c7al\u0131\u015fmada yakla\u015f\u0131k 19.000 RNA polimeraz II ve 15.000 NF-kappa B ba\u011flanma b\u00f6lgesi bulunmu\u015f. Ayr\u0131ca ara\u015ft\u0131rmada, bu farkl\u0131 ba\u011flanma b\u00f6lgelerinin \u00fc\u00e7te birinin tek n\u00fckleotid farkl\u0131l\u0131klar\u0131n\u0131n (SNPs) ve genomik yap\u0131sal \u00e7e\u015fitlili\u011fin (SVs) oldu\u011fu b\u00f6lgelerden kaynakland\u0131\u011f\u0131 bulunmu\u015f. \u0130lk defa bu \u00e7al\u0131\u015fmayla, gen ifadesinin kontrol\u00fcn\u00fc sa\u011flayan bir\u00e7ok d\u00fczenleyici elementin SNP\u2019lerden ve yap\u0131sal \u00e7e\u015fitlilikten etkilendi\u011fi g\u00f6sterilmi\u015f.<\/p>\n

\u00c7al\u0131\u015fmada ayr\u0131ca RNA polimeraz II ve NF-kappa B ba\u011flanma farkl\u0131l\u0131klar\u0131n\u0131n, tip 1 diyabet, l\u00f6semi, ast\u0131m, \u015fizofreni ve Crohn hastal\u0131\u011f\u0131 gibi bir\u00e7ok hastal\u0131\u011f\u0131n g\u00f6r\u00fcld\u00fc\u011f\u00fc gen b\u00f6lgelerine de yak\u0131n oldu\u011fu g\u00f6sterilmi\u015f. Gen d\u00fczenleyicilerindeki farkl\u0131l\u0131klar, pop\u00fclasyondaki hastal\u0131klar\u0131n \u00e7e\u015fitlilik \u015f\u00fcphelerini de ortaya koymaya yard\u0131mc\u0131 olabilir.\"\"<\/p>\n

Di\u011fer taraftan \u00e7al\u0131\u015fmada kullan\u0131lan \u015fempanze ve insan aras\u0131ndaki RNA polimeraz II ba\u011flanma b\u00f6lgelerinin y\u00fczde 32 farkl\u0131l\u0131k g\u00f6sterdi\u011fi belirtilmi\u015f. Ara\u015ft\u0131rmac\u0131lar, iki insan aras\u0131ndaki fark\u0131n y\u00fczde 25 oldu\u011fu g\u00f6z \u00f6n\u00fcnde tutulursa asl\u0131nda y\u00fczde 32 farkl\u0131l\u0131\u011f\u0131n \u00e7ok ciddi olmad\u0131\u011f\u0131n\u0131 belirtiyorlar.<\/p>\n

Bilim insanlar\u0131, yapm\u0131\u015f olduklar\u0131 \u00e7al\u0131\u015fmayla, bireyler ve t\u00fcrler aras\u0131ndaki bir\u00e7ok farkl\u0131l\u0131\u011f\u0131n transkripsiyon fakt\u00f6r\u00fcn\u00fcn ba\u011flanma seviyesinden kaynakland\u0131\u011f\u0131n\u0131 g\u00f6steriyorlar.<\/p>\n

Kaynaklar<\/strong><\/p>\n

(1) http:\/\/www.sciencedaily.com\/releases\/2010\/03\/100318141536.htm<\/p>\n

(2) http:\/\/www.bioquicknews.com\/node\/311<\/p>\n","protected":false},"excerpt":{"rendered":"

Ara\u015ft\u0131rmac\u0131lar uzun bir s\u00fcredir bir insan\u0131n di\u011ferinden fark\u0131n\u0131n sadece genlerden kaynakland\u0131\u011f\u0131n\u0131 d\u00fc\u015f\u00fcn\u00fcyorlard\u0131. Genler, h\u00fccrenin i\u015flerini yapabilmesi i\u00e7in gerekli olan proteinlerin yap\u0131m\u0131 i\u00e7in gerekli komutlar\u0131 ta\u015f\u0131rlar. T\u00fcm insanlar aras\u0131ndaki gen \u00e7e\u015fitlili\u011fi yakla\u015f\u0131k y\u00fczde 0,025\u2019dir. Bilim insanlar\u0131 uzun y\u0131llard\u0131r bu ufak farkl\u0131l\u0131\u011fa bakarak kim ve ne oldu\u011fumuzu anlamaya \u00e7al\u0131\u015f\u0131yorlar. Di\u011fer taraftan genomumuzda her hangi bir protein sentezi […]<\/p>\n","protected":false},"author":818,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[111,19,231],"tags":[272],"class_list":["post-10926","post","type-post","status-publish","format-standard","hentry","category-74-sayi","category-bilim-gundemi","category-molekuler-biyoloji-ve-genetik","tag-dna"],"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