{"id":49343,"date":"2021-03-25T12:49:08","date_gmt":"2021-03-25T09:49:08","guid":{"rendered":"https:\/\/bilimvegelecek.com.tr\/?p=49343"},"modified":"2021-03-25T12:49:08","modified_gmt":"2021-03-25T09:49:08","slug":"insan-beyni-kuyruksuz-maymunlarin-beyninden-daha-buyuk-hale-nasil-geldi","status":"publish","type":"post","link":"https:\/\/bilimvegelecek.com.tr\/index.php\/2021\/03\/25\/insan-beyni-kuyruksuz-maymunlarin-beyninden-daha-buyuk-hale-nasil-geldi","title":{"rendered":"\u0130nsan beyni, kuyruksuz maymunlar\u0131n beyninden daha b\u00fcy\u00fck hale nas\u0131l geldi?"},"content":{"rendered":"

\u0130nsan beyninin \u015fempanze ve goril beyninden nas\u0131l \u00e7ok daha b\u00fcy\u00fck oldu\u011funu ve \u00fc\u00e7 kat fazla n\u00f6ronla nas\u0131l \u00e7al\u0131\u015ft\u0131\u011f\u0131n\u0131 inceleyen bir ara\u015ft\u0131rma Cell<\/em> dergisinde yay\u0131nland\u0131. Cambridge’deki T\u0131bbi Ara\u015ft\u0131rma Konseyi (MRC) Molek\u00fcler Biyoloji Laboratuvar\u0131\u2019ndan biliminsanlar\u0131nca y\u00fcr\u00fct\u00fclen ara\u015ft\u0131rmada, kuyruksuz maymunlar\u0131n (ape) beyin organoidlerinin insan beyin organoidleri gibi b\u00fcy\u00fcmesini sa\u011flayan anahtar molek\u00fcler dizi tan\u0131mland\u0131.<\/p>\n

Ara\u015ft\u0131rmada insan, goril ve \u015fempanze k\u00f6k h\u00fccrelerinden \u00fcretilen \u201cbeyin organoidleri\u201d kar\u015f\u0131la\u015ft\u0131r\u0131ld\u0131. Beyin organoidleri erken beyin geli\u015fimini modelleyen ve k\u00f6k h\u00fccrelerden \u00fcretilen \u00fc\u00e7 boyutlu dokulard\u0131r. Ger\u00e7ek beyin boyutlar\u0131na benzer bir \u015fekilde, insan beyni organoidleri di\u011fer maymunlar\u0131n beyin organoidlerinden \u00e7ok daha b\u00fcy\u00fckt\u00fc.<\/p>\n

Dr. Madeline Lancaster, \u201cBizi ya\u015fayan en yak\u0131n akrabalar\u0131m\u0131zdan ay\u0131ran insan beyni hakk\u0131nda neyin farkl\u0131 oldu\u011funa dair i\u00e7g\u00f6r\u00fc sa\u011flayan bir ara\u015ft\u0131rma. Kuyruksuz maymunlarla aram\u0131zdaki en \u00e7arp\u0131c\u0131 fark, beyinlerimizin ne kadar inan\u0131lmaz bir b\u00fcy\u00fckl\u00fckte oldu\u011fudur\u201d a\u00e7\u0131klamalar\u0131nda bulundu. N\u00f6ronlar beyin geli\u015fiminin erken a\u015famalar\u0131nda, \u201cn\u00f6ral progenit\u00f6rler\u201d olarak adland\u0131r\u0131lan k\u00f6k h\u00fccreler taraf\u0131ndan olu\u015fturulur. Progenit\u00f6r h\u00fccreler ba\u015flang\u0131\u00e7ta silindirik bir \u015fekle sahiptir, b\u00f6ylece benzer \u015fekillerde, \u00f6zde\u015f yavru h\u00fccrelerin olu\u015fmas\u0131 kolayla\u015f\u0131r. Bu a\u015famada n\u00f6ral progenit\u00f6rler ne kadar \u00e7o\u011fal\u0131rsa, daha sonra o kadar \u00e7ok n\u00f6ron olu\u015facakt\u0131r.<\/p>\n

H\u00fccreler olgunla\u015ft\u0131k\u00e7a, \u00e7o\u011falmalar\u0131 da yava\u015flad\u0131k\u00e7a uzarlar ve koni benzeri bir \u015fekle d\u00f6n\u00fc\u015f\u00fcrler. \u0130nsan n\u00f6ral progenit\u00f6r h\u00fccreleri silindir \u015feklini di\u011fer maymunlardan daha uzun s\u00fcre korumaktayd\u0131 ve daha s\u0131k b\u00f6l\u00fcnerek daha fazla h\u00fccre \u00fcretiyorlard\u0131. N\u00f6ral progenit\u00f6rlerden n\u00f6ronlara ge\u00e7i\u015f h\u0131z\u0131ndaki fark, insanlardaki h\u00fccrelerin \u00e7o\u011falmak i\u00e7in daha fazla zamana sahip oldu\u011funu g\u00f6sterir. Bu durum, insan beyninin goril veya \u015fempanze beyinlerine k\u0131yasla daha fazla say\u0131da n\u00f6rona sahip olmas\u0131n\u0131 a\u00e7\u0131klayabilir.<\/p>\n

Ara\u015ft\u0131rmac\u0131lar ayr\u0131ca bu farklar\u0131n genetik k\u00f6kenini de inceledi, insan beyin organoidlerindeki gen anlat\u0131m d\u00fczeyini di\u011fer maymunlardakiyle kar\u015f\u0131la\u015ft\u0131rd\u0131. Goril beyin organoidlerinde insan beyin organoidlerine g\u00f6re daha erken d\u00f6nemde devreye giren \u201cZEB2\u201d genini tespit ettiler. ZEB2’nin etkisini geciktiren ara\u015ft\u0131rmac\u0131lar, progenit\u00f6r h\u00fccrelerin daha yava\u015f olgunla\u015ft\u0131\u011f\u0131n\u0131 ve goril beyin organoidlerinin insandakilere benzer \u015fekilde geli\u015fti\u011fini g\u00f6rd\u00fc. Bu durum tam tersi i\u00e7in de ge\u00e7erliydi. \u0130nsan progenit\u00f6r h\u00fccrelerinde ZEB2 genini daha erken bir d\u00f6nemde anlat\u0131m yapmaya te\u015fvik etmek, insan organoidlerinde erken ge\u00e7i\u015fi sa\u011flad\u0131, geli\u015fim maymun organoidlerindeki gibiydi.<\/p>\n

Biliminsanlar\u0131 organoidlerin sadece bir model oldu\u011funu ve t\u00fcm modeller gibi ger\u00e7ek beyinleri tam olarak yans\u0131tmad\u0131\u011f\u0131n\u0131 belirtiyorlar. Fakat yine de evrimimiz hakk\u0131ndaki temel sorular\u0131 daha iyi anlamam\u0131z i\u00e7in bir basamak g\u00f6revi g\u00f6rebilirler.<\/p>\n

Kaynak:<\/strong> SCIENCE DAILY<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

\u0130nsan beyninin \u015fempanze ve goril beyninden nas\u0131l \u00e7ok daha b\u00fcy\u00fck oldu\u011funu ve \u00fc\u00e7 kat fazla n\u00f6ronla nas\u0131l \u00e7al\u0131\u015ft\u0131\u011f\u0131n\u0131 inceleyen bir ara\u015ft\u0131rma Cell dergisinde yay\u0131nland\u0131. Cambridge’deki T\u0131bbi Ara\u015ft\u0131rma Konseyi (MRC) Molek\u00fcler Biyoloji Laboratuvar\u0131\u2019ndan biliminsanlar\u0131nca y\u00fcr\u00fct\u00fclen ara\u015ft\u0131rmada, kuyruksuz maymunlar\u0131n (ape) beyin organoidlerinin insan beyin organoidleri gibi b\u00fcy\u00fcmesini sa\u011flayan anahtar molek\u00fcler dizi tan\u0131mland\u0131. Ara\u015ft\u0131rmada insan, goril ve \u015fempanze […]<\/p>\n","protected":false},"author":1390,"featured_media":39714,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[19,32],"tags":[254,200,292,7473],"class_list":["post-49343","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bilim-gundemi","category-evrim","tag-beyin","tag-evrim","tag-genetik","tag-kuyruksuz-maymun"],"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\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t