Department of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America.
PLoS One. 2010 Feb 8;5(2):e9105. doi: 10.1371/journal.pone.0009105.
Identification of receptor mediated signaling pathways in embryonic stem (ES) cells is needed to facilitate strategies for cell replacement using ES cells. One large receptor family, largely uninvestigated in ES cells, is G protein coupled receptors (GPCRs). An important role for these receptors in embryonic development has been described, but little is known about GPCR expression in ES cells.
METHODOLOGY/PRINCIPAL FINDINGS: We have examined the expression profile of 343 different GPCRs in mouse ES cells demonstrating for the first time that a large number of GPCRs are expressed in undifferentiated and differentiating ES cells, and in many cases at high levels. To begin to define a role for GPCR signaling in ES cells, the impact of activating Gs-alpha, one of the major alpha subunits that couples to GPCRs, was investigated. Gs-alpha activation resulted in larger embryoid bodies (EBs), due, in part, to increased cell proliferation and prevented the time-related decline in expression of transcription factors important for maintaining ES cell pluripotency.
SIGNIFICANCE/CONCLUSIONS: These studies suggest that Gs-alpha signaling contributes to ES cell proliferation and pluripotency and provide a framework for further investigation of GPCRs in ES cells.
为了促进利用胚胎干细胞进行细胞替代的策略,需要确定胚胎干细胞中受体介导的信号通路。G 蛋白偶联受体(GPCR)是一个很大的受体家族,在胚胎干细胞中尚未得到广泛研究。这些受体在胚胎发育中起着重要作用,但关于它们在胚胎干细胞中的表达知之甚少。
方法/主要发现:我们检测了 343 种不同的 GPCR 在小鼠胚胎干细胞中的表达谱,首次证明了大量 GPCR 在未分化和分化的胚胎干细胞中表达,而且在许多情况下表达水平很高。为了开始定义 GPCR 信号在胚胎干细胞中的作用,我们研究了激活 Gs-alpha 的影响,Gs-alpha 是与 GPCR 偶联的主要α亚基之一。Gs-alpha 的激活导致更大的类胚体(EBs),部分原因是细胞增殖增加,并防止了与时间相关的转录因子表达下降,这些转录因子对维持胚胎干细胞多能性很重要。
意义/结论:这些研究表明,Gs-alpha 信号通路有助于胚胎干细胞的增殖和多能性,并为进一步研究胚胎干细胞中的 GPCR 提供了框架。