Institute of Physiology, University of Hohenheim, Garbenstr. 30, 70599, Stuttgart, Germany.
Cell Mol Life Sci. 2010 Jun;67(11):1859-69. doi: 10.1007/s00018-010-0296-8. Epub 2010 Feb 18.
Localized to the vestibule of the nasal cavity, neurons of the Grueneberg ganglion (GG) respond to cool ambient temperatures. The molecular mechanisms underlying this thermal response are still elusive. Recently, it has been suggested that cool temperatures may activate a cyclic guanosine monophosphate (cGMP) pathway in the GG, which would be reminiscent of thermosensory neurons in Caenorhabditis elegans. In search for other elements of such a cascade, we have found that the cyclic nucleotide-gated ion channel CNGA3 was strongly expressed in the GG and that expression of CNGA3 was confined to those cells that are responsive to coolness. Further experiments revealed that the response of GG neurons to cool temperatures was significantly reduced in CNGA3-deficient mice compared to wild-type conspecifics. The observation that a cGMP-activated non-selective cation channel significantly contributes to the coolness-evoked response in GG neurons strongly suggests that a cGMP cascade is part of the transduction process.
定位于鼻腔前庭的 Grüneberg 神经节 (GG) 神经元对环境低温有反应。这种热反应的分子机制仍不清楚。最近，有人提出，低温可能会激活 GG 中的环鸟苷酸单磷酸 (cGMP) 途径，这让人联想到秀丽隐杆线虫中的热敏神经元。为了寻找这种级联反应的其他因素，我们发现环状核苷酸门控离子通道 CNGA3 在 GG 中强烈表达，并且 CNGA3 的表达仅限于对凉爽有反应的细胞。进一步的实验表明，与野生型同窝仔相比，CNGA3 缺陷小鼠 GG 神经元对低温的反应明显降低。观察到 cGMP 激活的非选择性阳离子通道对 GG 神经元的冷刺激反应有显著贡献，这强烈表明 cGMP 级联反应是转导过程的一部分。
