來自新加坡基因組研究所(GIS)和細胞和分子生物學研究所(IMCB)的科學家發(fā)現(xiàn)了人類干細胞“百變”的秘密,而且只要啟動這個被稱為PRDM14的基因,,任何普通細胞都有可能“變身”為干細胞,,成功率比現(xiàn)有技術(shù)高三倍。該研究發(fā)表于10月17日的Nature雜志上,。
擁有多能性(pluripotency)的胚胎干細胞(embryonic stem cell),,能變成人體里200多種細胞中的任何一種,自我“繁殖”能力也強,,因此一直被視為各種絕癥的希望,。不過,由于牽涉道德問題,,胚胎干細胞研究一再受阻,,科學家只好另覓良方。
科學人員近年就開始鉆研“培育”多能性干細胞的可能性,,通過重編程(re-programme)改變細胞基因,,讓普通細胞也具多能性,。由19名本地科學家組成的研究小組就花了三年,從2萬1000組基因中,,找到了干細胞“多能性”的重要鑰匙,。
據(jù)稱這是有史至今,最大規(guī)模的干細胞基因研究,。
干細胞專題
2010年干細胞技術(shù)與應用講座
干細胞發(fā)展編年史
全球五大干細胞治療中心
解讀干細胞臨床應用標準與規(guī)則
干細胞之春——生物谷盤點2009
華夏干細胞產(chǎn)業(yè)技術(shù)創(chuàng)新戰(zhàn)略聯(lián)盟正式成立
參與研究的新加坡基因組研究院高級研究小組組長黃學暉博士受訪時指出,,要讓普通細胞具多能性,需啟動的基因有好幾組,,PRDM14只是其中之一,,但它卻也扮演著重要角色。
小組發(fā)現(xiàn),,在改造細胞時如果為細胞“添置”PRDM14基因組,,那最終培育出具多能性的細胞,將比平日多出三倍,。
此外,,他們也發(fā)現(xiàn)PRDM14只在人類的干細胞中扮演重要角色,對老鼠干細胞則不重要,。這顯示了不同物種間干細胞的差異,,也再次彰顯了以人類細胞進行研究的重要性。
黃博士說:“在此之前,,研究員對人類胚胎干細胞的基因組合認識很少,,多數(shù)試驗室都專注用老鼠細胞進行研究。但了解人類干細胞其實很重要,,如果不了解,,我們又怎能研發(fā)新的科技。”
不過黃博士坦誠,,目前還不清楚這項發(fā)現(xiàn)能如何應用于醫(yī)藥治療,。“除了PRDM14,我們目前還在研究很多其他的基因組,。當中一些可能對個別病癥具重要功能,。”
“目前我們很難推算出一個時間表,正如很多重要的治療,,從發(fā)現(xiàn)到最終的臨床應用是需要時間的,。”
雖有人擔心,重新編排細胞基因可能會啟動不良副作用,,但黃博士認為,,隨著更多關(guān)鍵基因獲辨識,重新編排細胞基因的方式也將更完善,。
黃博士表示,,目前一些常見的干細胞療法用的都是他人捐贈的干細胞,,可是新的研究卻能直接用病人本身的細胞“培育”出干細胞,仿佛是為病人“量身”制定,,相信會更理想,。
接下來,研究小組將繼續(xù)探討如何更好地為普通細胞“添置”PRDM14基因,,以及如何利用基因?qū)W科技“指引”干細胞“變身”成為個別種類的細胞,。(生物谷Bioon.com)
生物谷推薦英文摘要:
Nature advance online publication 17 October 2010 | doi:10.1038/nature09531
A genome-wide RNAi screen reveals determinants of human embryonic stem cell identity
Na-Yu Chia1,2,10, Yun-Shen Chan1,3,10, Bo Feng1,10, Xinyi Lu1,4, Yuriy L. Orlov5, Dimitri Moreau6, Pankaj Kumar6, Lin Yang1, Jianming Jiang1, Mei-Sheng Lau1, Mikael Huss5, Boon-Seng Soh7, Petra Kraus7, Pin Li7, Thomas Lufkin7, Bing Lim7,8, Neil D. Clarke5,9, Frederic Bard6,9 & Huck-Hui Ng1,2,3,4,9
The derivation of human ES cells (hESCs) from human blastocysts represents one of the milestones in stem cell biology1. The full potential of hESCs in research and clinical applications requires a detailed understanding of the genetic network that governs the unique properties of hESCs. Here, we report a genome-wide RNA interference screen to identify genes which regulate self-renewal and pluripotency properties in hESCs. Interestingly, functionally distinct complexes involved in transcriptional regulation and chromatin remodelling are among the factors identified in the screen. To understand the roles of these potential regulators of hESCs, we studied transcription factor PRDM14 to gain new insights into its functional roles in the regulation of pluripotency. We showed that PRDM14 regulates directly the expression of key pluripotency gene POU5F1 through its proximal enhancer. Genome-wide location profiling experiments revealed that PRDM14 colocalized extensively with other key transcription factors such as OCT4, NANOG and SOX2, indicating that PRDM14 is integrated into the core transcriptional regulatory network. More importantly, in a gain-of-function assay, we showed that PRDM14 is able to enhance the efficiency of reprogramming of human fibroblasts in conjunction with OCT4, SOX2 and KLF4. Altogether, our study uncovers a wealth of novel hESC regulators wherein PRDM14 exemplifies a key transcription factor required for the maintenance of hESC identity and the reacquisition of pluripotency in human somatic cells.
1Gene Regulation Laboratory, Genome Institute of Singapore, 60 Biopolis Street, Singapore 138672
2School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
3Graduate School for Integrative Sciences & Engineering, National University of Singapore, 28 Medical Drive, Singapore 117456
4Dept of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543
5Computational and Systems Biology group, Genome Institute of Singapore, 60 Biopolis Street, Singapore 138672
6Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, Singapore 138673
7Stem Cell and Developmental Biology, Genome Institute of Singapore, 60 Biopolis Street, Singapore 138672
8Center for Life Sciences, Harvard Medical School, 330 Brookline Avenue, Boston, Massachusetts 02115, USA
9Department of Biochemistry, National University of Singapore, 8 Medical Drive, Yong Loo Lin School of Medicine, Singapore 117597
10These authors contributed equally to this work.