Targeted in Vivo O-GlcNAc Sensors Reveal Discrete Compartment-specific Dynamics during Signal Transduction
Targeted in Vivo O-GlcNAc Sensors Reveal Discrete Compartment-specific Dynamics during Signal Transduction
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DOI：
10.1074/jbc.m110.191627
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发表时间：
2011-02-25
影响因子：
4.8
通讯作者：
Mahal, Lara K.
中科院分区：
文献类型：
--
作者：
Carrillo, Luz D.;Froemming, Joshua A.;Mahal, Lara K.
β-O-N-乙酰-D-氨基葡萄糖(O-GlcNAc)是一种翻译后修饰，涉及从细胞应激到胰岛素信号转导等多种生物系统。这种修饰与磷酸化有许多共同的特征，包括它动态地循环到一系列蛋白质上，如转录因子、激酶和磷酸酶，以及对细胞功能的调节，包括细胞信号。在这里，我们报道了一种改进的基于遗传的O-GlcNAc FRET传感器的发展和用于表征O-GlcNAc时空动力学的分区靶向变体。在血清刺激的信号转导过程中，O-GlcNAc活性在细胞膜和胞核均迅速升高，胞浆中也随之降低。这些发现表明O-GlcNAc对信号诱导刺激的反应存在隔室特异性动力学，表明这种修饰的复杂调控。此外，Wortmannin对PI3K途径的抑制取消了O-GlcNAc反应，表明观察到的活性是在PI3K途径下游调节的。综上所述，我们的数据认为O-GlcNAc是一种快速诱导的信号成分，O-GlcNAc与激酶信号之间的相互作用可能更类似于激酶通路之间的复杂关系。
beta-O-N-acetyl-D-glucosamine (O-GlcNAc) is a post-translational modification involved in a plethora of biological systems ranging from cellular stress to insulin signaling. This modification shares many hallmarks with phosphorylation, including its dynamic cycling onto a host of proteins such as transcription factors, kinases, and phosphatases, and regulation of cellular functions, including cell signaling. Herein, we report the development of an improved genetically based O-GlcNAc FRET sensor and compartmentalized targeted variants for the characterization of the spatiotemporal dynamics of O-GlcNAc. During serum-stimulated signal transduction, rapid increases in O-GlcNAc activity were observed at both the plasma membrane and the nucleus, with a concomitant decrease detected in the cytoplasm. These findings suggest the existence of compartment specific dynamics for O-GlcNAc in response to signal-inducing stimuli, pointing to complex regulation of this modification. In addition, inhibition of the PI3K pathway by wortmannin abolished the O-GlcNAc response, suggesting that the activity observed is modulated downstream of the PI3K pathway. Taken together, our data argues that O-GlcNAc is a rapidly induced component of signaling and that the interplay between O-GlcNAc and kinase signaling may be more akin to the complex relationship between kinase pathways.