Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, Illinois 60607, USA.
Cold Spring Harb Perspect Biol. 2012 Sep 1;4(9):a007971. doi: 10.1101/cshperspect.a007971.
Embryonic stem cells (ESCs) can generate all of the cell types found in the adult organism. Remarkably, they retain this ability even after many cell divisions in vitro, as long as the culture conditions prevent differentiation of the cells. Wnt signaling and β-catenin have been shown to cause strong effects on ESCs both in terms of stimulating the expansion of stem cells and stimulating differentiation toward lineage committed cell types. The varied effects of Wnt signaling in ESCs, alongside the sometimes unconventional mechanisms underlying the effects, have generated a fair amount of controversy and intrigue regarding the role of Wnt signaling in pluripotent stem cells. Insights into the mechanisms of Wnt function in stem cells can be gained by examination of the causes for seemingly opposing effects of Wnt signaling on self-renewal versus differentiation.
胚胎干细胞 (ESCs) 可以生成成年生物体中所有的细胞类型。值得注意的是，只要培养条件阻止细胞分化，它们在体外经历多次细胞分裂后仍保留这种能力。Wnt 信号和 β-连环蛋白已被证明对 ESCs 具有强烈的影响，既可以刺激干细胞的扩增，又可以刺激向谱系定向细胞类型的分化。Wnt 信号在 ESCs 中的不同作用，以及其作用背后有时非常规的机制，引发了关于 Wnt 信号在多能干细胞中的作用的大量争议和兴趣。通过检查 Wnt 信号对自我更新与分化的看似相反作用的原因，可以深入了解 Wnt 功能在干细胞中的机制。
