Biochemical Technologies, Science and Technology Division, Corning Inc., Corning, New York, USA.
Nat Chem Biol. 2011 Oct 23;7(12):909-15. doi: 10.1038/nchembio.690.
G protein-coupled receptors (GPCRs) transmit exogenous signals to the nucleus, promoting a myriad of biological responses via multiple signaling pathways in both healthy and cancerous cells. However, little is known about the response of cytosolic metabolic pathways to GPCR-mediated signaling. Here we applied fluorescent live-cell imaging and label-free dynamic mass redistribution assays to study whether purine metabolism is associated with GPCR signaling. Through a library screen of GPCR ligands in conjunction with live-cell imaging of a metabolic multienzyme complex for de novo purine biosynthesis, the purinosome, we demonstrated that the activation of endogenous Gα(i)-coupled receptors correlates with purinosome assembly and disassembly in native HeLa cells. Given the implications of GPCRs in mitogenic signaling and of the purinosome in controlling metabolic flux via de novo purine biosynthesis, we hypothesize that regulation of purinosome assembly and disassembly may be one of the downstream events of mitogenic GPCR signaling in human cancer cells.
G 蛋白偶联受体 (GPCRs) 将外源性信号传递到细胞核，通过健康细胞和癌细胞中的多种信号通路促进多种生物学反应。然而，对于细胞溶质代谢途径对 GPCR 介导的信号的反应知之甚少。在这里，我们应用荧光活细胞成像和无标记动态质量重分布测定来研究嘌呤代谢是否与 GPCR 信号有关。通过结合使用 GPCR 配体文库筛选和用于从头合成嘌呤生物合成的代谢多酶复合物荧光活细胞成像，即嘌呤体，我们证明了内源性 Gα(i)偶联受体的激活与天然 HeLa 细胞中嘌呤体的组装和拆卸相关。鉴于 GPCRs 在有丝分裂信号中的作用以及嘌呤体在通过从头合成嘌呤控制代谢通量方面的作用，我们假设嘌呤体组装和拆卸的调节可能是人类癌细胞中促有丝分裂 GPCR 信号的下游事件之一。
