Odorant-stimulated phosphoinositide signaling in mammalian olfactory receptor neurons
Odorant-stimulated phosphoinositide signaling in mammalian olfactory receptor neurons
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DOI：
10.1016/j.cellsig.2009.09.026
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发表时间：
2010-01-01
影响因子：
4.8
通讯作者：
Ache, B. W.
中科院分区：
文献类型：
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作者：
Klasen, K.;Corey, E. A.;Ache, B. W.
最近的证据重新激起了人们对磷酸肌醇 (PI) 可能在哺乳动物嗅觉受体神经元 (ORN) 信号转导中发挥作用的观点的兴趣。为了提供气味剂确实激活 ORN 中 PI 信号传导的直接证据，我们使用携带两种不同荧光标记探针（磷脂酶 C delta 1 (PLC delta 1) 的普莱克斯特林同源 (PH) 结构域和磷酸肌醇通用受体 (GRP1)）的腺病毒载体来监测体内 ORN 树突状突起中的 PI 活性。气味剂动员了 PI(4,5)P(2)/IP(3) 和 PI(3,4,5)P(3)，即 PLC 和 PI3K 的底物和产物。然后，我们使用磷脂覆盖测定和 ELISA 在体外测量了富含嗅纤毛膜中 PLC 和 PI3K 的气味激活。气味剂在气味刺激后 2 秒内激活嗅觉纤毛中的 PLC 和 PI3K。嗅觉上皮中 PLC 和 PI3K 的气味依赖性激活可以被酶特异性抑制剂阻断。气味剂激活 PLC 和 PI3K，具有部分重叠的特异性。这些结果提供了直接证据，表明气味剂确实激活哺乳动物 ORN 中的 PI 信号传导，其方式与 PI 信号传导在嗅觉转导中发挥作用的观点一致。 (C) 2009 Elsevier Inc. 保留所有权利。
Recent evidence has revived interest in the idea that phosphoinositides (PIs) may play a role in signal transduction in mammalian olfactory receptor neurons (ORNs). To provide direct evidence that odorants indeed activate PI signaling in ORNs, we used adenoviral vectors carrying two different fluorescently tagged probes, the pleckstrin homology (PH) domains of phospholipase C delta 1 (PLC delta 1) and the general receptor of phosphoinositides (GRP1), to monitor PI activity in the dendritic knobs of ORNs in vivo. Odorants mobilized PI(4,5)P(2)/IP(3) and PI(3,4,5)P(3), the substrates and products of PLC and PI3K. We then measured odorant activation of PLC and PI3K in olfactory ciliary-enriched membranes in vitro using a phospholipid overlay assay and ELISAs. Odorants activated both PLC and PI3K in the olfactory cilia within 2 s of odorant stimulation. Odorant-dependent activation of PLC and PI3K in the olfactory epithelium could be blocked by enzyme-specific inhibitors. Odorants activated PLC and PI3K with partially overlapping specificity. These results provide direct evidence that odorants indeed activate PI signaling in mammalian ORNs in a manner that is consistent with the idea that PI signaling plays a role in olfactory transduction. (C) 2009 Elsevier Inc. All rights reserved.