西亚试剂：An alternative pluripotent state confers interspecies chima

Pluripotency, the ability to generate any cell type of the body, is an evanescent attribute of embryonic cells. Transitory pluripotent cells can be captured at different time points during embryogenesis and maintained as embryonic stem cells or epiblast stem cells in culture. Since ontogenesis is a dynamic process in both space and time, it seems counterintuitive that these two temporal states represent the full spectrum of organismal pluripotency. Here we show that by modulating culture parameters, a stem-cell type with unique spatial characteristics and distinct molecular and functional features, designated as region-selecive pluripotent stem cells (rsPSCs), can be efficiently obtained from mouse embryos and primate pluripotent stem cells, including humans. The ease of culturing and editing the genome of human rsPSCs offers advantages for regenerative medicine applications. The unique ability of human rsPSCs to generate post-implantation interspecies chimaeric embryos may facilitate our understanding of early human development and evolution.胚胎干细胞和外胚层干细胞代表着两个被普遍接受的多能状态，它们来自小鼠胚胎发生过程的不同时间点。通过调制用于从小鼠外胚层提取多能干细胞的培养基中的信号传导成分，Izpisua Belmonte及同事识别出了具有与这两类干细胞截然不同特点的另一个干细胞状态。这些细胞能被植入小鼠外胚层的特定区域，因而被称为 “区域选择性多能干细胞”(rsPSCs)。具有相似特性的细胞也从小鼠和灵长类多能干细胞系的培养中获得了。对rsPSCs进行研究将使我们对哺乳动物发育有进一步的认识。