We have previously shown that insect vanilloid-type transient receptor potential (TRPV) channels Nanchung (Nan) and Inactive (Iav) form complexes, which can be over-stimulated and eventually silenced by commercial insecticides, afidopyropen, pymetrozine and pyrifluquinazon. Silencing of the TRPV channels by the insecticides perturbs function of the mechano-sensory organs, chordotonal organs, disrupting sound perception, gravitaxis, and feeding. In addition to TRPV channels, chordotonal organs express an ankyrin-type transient receptor potential (TRPA) channel, Water witch (Wtrw). Genetic data implicate Wtrw in sound and humidity sensing, although the signaling pathway, which links Wtrw to these functions has not been clearly defined. Here we show that, in heterologous system, Nan and Wtrw form calcium channels, which can be activated by afidopyropen, pymetrozine and an endogenous agonist, nicotinamide. Analogous to Nan-Iav heteromers, Nan forms the main binding interface for afidopyropen, whereas co-expression of Wtrw dramatically increases its binding affinity. Pymetrozine competes with afidopyropen for binding to Nan-Wtrw complexes, suggesting that these compounds have overlapping binding sites. Analysis of Drosophila single-nucleus transcriptomic atlas revealed co-expression of nan and wtrw in audio- and mechanosensory neurons. The observation that Nan can form insecticide-sensitive heteromers with more than one type of TRP channels, raises a possibility that Nan may partner with some other TRP channel(s). In addition, we show that Wtrw can be activated by plant-derived reactive electrophiles, allyl isothiocyanate and cinnamaldehyde, defining new molecular target for these repellents.

我们之前已经表明，昆虫类香草素型瞬时受体电位(TRPV) 通道 Nanchung (Nan) 和非活性 (Iav) 形成复合物，这些复合物可以被商业杀虫剂 afidopyropen、pymetrozine 和 pyrifluquinazon 过度刺激并最终沉默。杀虫剂对 TRPV通道的沉默会扰乱机械感觉器官、腱索器官的功能，破坏声音感知、重力和进食。除了 TRPV 通道外，脊索器官还表达锚蛋白型瞬时受体电位 (TRPA) 通道，即水女巫 (Wtrw)。遗传数据表明 Wtrw 与声音和湿度感应有关，尽管将Wtrw 与这些功能联系起来的信号通路尚未明确定义。在这里，我们表明，在异源系统中，Nan 和 Wtrw 形式钙通道，可由 afidopyropen、pymetrozine 和内源性激动剂烟酰胺激活。与 Nan-Iav 异聚体类似，Nan 形成了 afidopyropen 的主要结合界面，而 Wtrw 的共表达显着增加了其结合亲和力。Pymetrozine 与 afidopyropen 竞争结合 Nan-Wtrw 复合物，表明这些化合物具有重叠的结合位点。果蝇单核转录组图谱的分析揭示了nan和wtrw在听觉和机械感觉神经元中。Nan 可以形成具有一种以上 TRP 通道的杀虫剂敏感异聚体的观察结果提出了 Nan 可能与其他一些 TRP 通道合作的可能性。此外，我们表明 Wtrw 可以被植物衍生的反应性亲电试剂、异硫氰酸烯丙酯和肉桂醛激活，从而为这些驱虫剂定义了新的分子靶标。