英國劍橋大學21日發(fā)表新聞公報說,，該校研究人員確認一種名為“Nanog”的蛋白質(zhì)是干細胞具有發(fā)育成各種類型細胞能力的“總開關”。無論是在胚胎干細胞還是誘導多能干細胞中,，它都起著關鍵作用,。
人類胚胎細胞具有神奇的全能性，可以隨著胚胎成長而發(fā)育成人體不同器官的細胞,，如骨骼,、皮膚、內(nèi)臟,、神經(jīng)等各種細胞,。近年來，科學家又發(fā)現(xiàn)可通過基因改造使普通皮膚細胞等具有與胚胎干細胞類似的全能性,，稱為誘導多能干細胞,。但是,，科學界一直不清楚這兩種細胞具有全能性的深層機理。
劍橋大學的新聞公報說,，該校研究人員發(fā)現(xiàn)“Nanog”蛋白質(zhì)在細胞獲得全能性的一系列復雜過程中發(fā)揮著非常關鍵的作用,。如果沒有它，胚胎干細胞將不會發(fā)育,，而誘導產(chǎn)生多功能干細胞的過程也會失敗,。
研究人員解釋說,，“Nanog”并不是單獨起作用,，它更像一個“樂隊指揮”，協(xié)調(diào)著一系列基因和蛋白質(zhì),，讓它們在各自正確的位置上發(fā)揮作用,，最終為細胞帶來神奇的全能性。研究人員將進一步研究這種蛋白質(zhì)是如何“發(fā)號施令”的,。
相關研究報告發(fā)表在新一期美國《細胞》雜志上,。（生物谷Bioon.com）
生物谷推薦原始出處：
Cell, Volume 138, Issue 4, 722-737, 21 August 2009 doi:10.1016/j.cell.2009.07.039
Nanog Is the Gateway to the Pluripotent Ground State
Jose Silva1,2,6,,,Jennifer Nichols1,3,6,Thorold W. Theunissen1,2,Ge Guo1,2,Anouk L. van Oosten1,2,Ornella Barrandon1,2,Jason Wray1,2,Shinya Yamanaka4,Ian Chambers5andAustin Smith1,2,,
1 Wellcome Trust Centre for Stem Cell Research, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
2 Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
3 Department of Physiology, Development, and Neuroscience, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
4 Department of Stem Cell Biology, Institute for Frontier Medical Sciences, Kyoto University, Kyoto 606-8507, Japan
5 MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, King's Buildings, Edinburgh EH9 3JQ, UK
Pluripotency is generated naturally during mammalian development through formation of the epiblast, founder tissue of the embryo proper. Pluripotency can be recreated by somatic cell reprogramming. Here we present evidence that the homeodomain protein Nanog mediates acquisition of both embryonic and induced pluripotency. Production of pluripotent hybrids by cell fusion is promoted by and dependent on Nanog. In transcription factor-induced molecular reprogramming, Nanog is initially dispensable but becomes essential for dedifferentiated intermediates to transit to ground state pluripotency. In the embryo, Nanog specifically demarcates the nascent epiblast, coincident with the domain of X chromosome reprogramming. Without Nanog, pluripotency does not develop, and the inner cell mass is trapped in a pre-pluripotent, indeterminate state that is ultimately nonviable. These findings suggest that Nanog choreographs synthesis of the naive epiblast ground state in the embryo and that this function is recapitulated in the culmination of somatic cell reprogramming.
