Biology and Biotechnology Department, Worcester Polytechnic Institute, Worcester, MA, 01605, USA.
BioHelix Corporation, Beverly, MA, 01915, USA.
Nat Commun. 2019 Jul 18;10(1):3186. doi: 10.1038/s41467-019-11240-7.
Biogenic amine neurotransmitters play a central role in metazoan biology, and both their chemical structures and cognate receptors are evolutionarily conserved. Their primary roles are in cell-to-cell signaling, as biogenic amines are not normally recruited for communication between separate individuals. Here, we show that in the nematode C. elegans, a neurotransmitter-sensing G protein-coupled receptor, TYRA-2, is required for avoidance responses to osas#9, an ascaroside pheromone that incorporates the neurotransmitter, octopamine. Neuronal ablation, cell-specific genetic rescue, and calcium imaging show that tyra-2 expression in the nociceptive neuron, ASH, is necessary and sufficient to induce osas#9 avoidance. Ectopic expression in the AWA neuron, which is generally associated with attractive responses, reverses the response to osas#9, resulting in attraction instead of avoidance behavior, confirming that TYRA-2 partakes in the sensing of osas#9. The TYRA-2/osas#9 signaling system represents an inter-organismal communication channel that evolved via co-option of a neurotransmitter and its cognate receptor.
生物胺神经递质在后生动物生物学中起着核心作用，其化学结构和同源受体在进化上是保守的。它们的主要作用是在细胞间信号传递，因为生物胺通常不会被招募用于不同个体之间的通信。在这里，我们表明在秀丽隐杆线虫中，一种神经递质感应 G 蛋白偶联受体 TYRA-2，对于对 osas#9 的回避反应是必需的，osas#9 是一种包含神经递质章鱼胺的副激素。神经元消融、细胞特异性遗传拯救和钙成像表明，在伤害感受神经元 ASH 中表达的 tyra-2 对于诱导 osas#9 回避是必要且充分的。在外周神经元 AWA 中的异位表达，通常与吸引反应相关联，会使对 osas#9 的反应反转，导致吸引而不是回避行为，这证实了 TYRA-2 参与了对 osas#9 的感知。TYRA-2/osas#9 信号系统代表了一种通过共选择神经递质及其同源受体而进化的种间通信通道。
