Drosophila menthol sensitivity and the Precambrian origins of transient receptor potential-dependent chemosensation
Drosophila menthol sensitivity and the Precambrian origins of transient receptor potential-dependent chemosensation
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DOI：
10.1098/rstb.2019.0369
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发表时间：
2019-09-23
影响因子：
6.3
通讯作者：
Cox, Daniel N.
中科院分区：
文献类型：
--
作者：
Himmel, Nathaniel J.;Letcher, Jamin M.;Cox, Daniel N.
瞬时受体电位（TRP）阳离子通道是一种高度保守的多模态传感器，对各种刺激都有反应。也许最值得注意的是，TRP通道在伤害感受和疼痛中发挥关键作用。越来越多的证据表明，瞬时受体电位melastatin（TRPM）和瞬时受体电位锚蛋白（TRPA）的热和亲电敏感性早于原口类-后口类分裂（大于550 Ma）。然而，TRPM和TRPA通道也被认为可以检测修饰的萜烯（例如薄荷醇）。虽然萜类化合物如薄荷醇被认为是令人厌恶的和/或有害的昆虫，机械敏感性研究已在很大程度上限于脊索动物。此外，还不知道TRP-薄荷醇感测是否与热和/或亲电敏感性一样古老。结合遗传，光学，电生理，行为和系统发育的方法，我们测试的假设，昆虫TRP通道在薄荷醇传感中发挥保守的作用。我们发现，局部应用薄荷醇的果蝇幼虫elimina的Trpm和TrpA 1依赖的伤害性滚动行为，这需要激活IV类伤害感受器神经元。此外，在表征的TRP通道的演变，我们提出的假设，三个以前未描述的TRPM通道分支（基础，α TRPM和β TRPM），以及TRP与薄荷醇sensing关键的残基，存在于祖先bilaterians.This文章的一部分，Theo墨菲会议的问题“进化的机制和行为的重要疼痛”。
Transient receptor potential (TRP) cation channels are highly conserved, polymodal sensors which respond to a wide variety of stimuli. Perhaps most notably, TRP channels serve critical functions in nociception and pain. A growing body of evidence suggests that transient receptor potential melastatin (TRPM) and transient receptor potential ankyrin (TRPA) thermal and electrophile sensitivities predate the protostome-deuterostome split (greater than 550 Ma). However, TRPM and TRPA channels are also thought to detect modified terpenes (e.g. menthol). Although terpenoids like menthol are thought to be aversive and/or harmful to insects, mechanistic sensitivity studies have been largely restricted to chordates. Furthermore, it is unknown if TRP-menthol sensing is as ancient as thermal and/or electrophile sensitivity. Combining genetic, optical, electrophysiological, behavioural and phylogenetic approaches, we tested the hypothesis that insect TRP channels play a conserved role in menthol sensing. We found that topical application of menthol to Drosophila melanogaster larvae elicits a Trpm- and TrpA1-dependent nocifensive rolling behaviour, which requires activation of Class IV nociceptor neurons. Further, in characterizing the evolution of TRP channels, we put forth the hypotheses that three previously undescribed TRPM channel clades (basal, alpha TRPM and beta TRPM), as well as TRPs with residues critical for menthol sensing, were present in ancestral bilaterians.This article is part of the Theo Murphy meeting issue 'Evolution of mechanisms and behaviour important for pain'.