Nature：人类胚胎干细胞的新调控因子

细胞海洋

如果要使人类胚胎干细胞在研究和临床应用中的全部潜力都发挥出来，我们便需要对掌控它们独特性质的遗传网络有一个细致的了解。
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一项全基因组RNA干涉扫描，在人类胚胎干细胞中识别出自我更新和多能性的大量新调控因子。例如，PRDM14是维持人类胚胎身份及体细胞向多能性重新编程所需的一个关键转录因子
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" Y8 Q* T+ v! Q$ ENature  doi:10.1038/nature09531
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A genome-wide RNAi screen reveals determinants of human embryonic stem cell identity2 d  C! W* p0 K; ^! W
Na-Yu Chia,Yun-Shen Chan,Bo Feng,Xinyi Lu,Yuriy L. Orlov,Dimitri Moreau,Pankaj Kumar,Lin Yang,Jianming Jiang,Mei-Sheng Lau,Mikael Huss,Boon-Seng Soh,Petra Kraus,Pin Li,Thomas Lufkin,Bing Lim,Neil D. Clarke,Frederic Bardfbard@imcb.a-star.edu.sg& Huck-Hui Ng
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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.