Department of Biology, Faculty of Sciences, University of Chile, Santiago 1058, Chile, Department of Cell and Developmental Biology, Neuroscience Program, and Rocky Mountain Taste and Smell Center, Anschutz Medical Campus, University of Colorado, Aurora, Colorado 80045.
J Neurosci. 2014 Feb 26;34(9):3268-78. doi: 10.1523/JNEUROSCI.4903-13.2014.
Growing evidence suggests that the main olfactory epithelium contains a subset of olfactory sensory neurons (OSNs) responding to pheromones. One candidate subpopulation expresses the calcium activated cation channel TRPM5 (transient receptor potential channel M5). Using GFP driven by the TRPM5 promoter in mice, we show that this subpopulation responds to putative pheromones, urine, and major histocompatibility complex peptides, but not to regular odors or a pheromone detected by other species. In addition, this subpopulation of TRPM5-GFP+ OSNs uses novel transduction. In regular OSNs, odorants elicit activation of the cyclic nucleotide-gated (CNG) channel, leading to Ca2+ gating of Cl- channels; in TRPM5-GFP+ OSNs, the Ca2+ -activated Cl- ANO2 (anoctamin 2) channel is not expressed, and pheromones elicit activation of the CNG channel leading to Ca2+ gating of TRPM5. In conclusion, we show that OSNs expressing TRPM5 respond to pheromones, but not to regular odors through the opening of CNG channels leading to Ca2+ gating of TRPM5.
越来越多的证据表明，主要嗅觉上皮包含对信息素起反应的一小部分嗅觉感觉神经元（OSN）。候选的亚群表达钙激活阳离子通道 TRPM5（瞬时受体电位通道 M5）。使用由 TRPM5 启动子驱动 GFP 的小鼠，我们表明该亚群对假定的信息素、尿液和主要组织相容性复合物肽有反应，但对常规气味或其他物种检测到的信息素没有反应。此外，TRPM5-GFP+ OSN 的这个亚群使用新的转导。在常规 OSN 中，气味剂引发环核苷酸门控（CNG）通道的激活，导致 Cl-通道的 Ca2+门控；在 TRPM5-GFP+ OSN 中，不表达 Ca2+激活的 Cl-ANO2（anoctamin 2）通道，并且信息素引发 CNG 通道的激活，导致 Ca2+门控 TRPM5。总之，我们表明表达 TRPM5 的 OSN 通过开启 CNG 通道对信息素做出反应，但不通过开启 CNG 通道对常规气味做出反应，从而导致 Ca2+门控 TRPM5。
