Dissecting the Signaling Mechanisms Underlying Recognition and Preference of Food Odors
Dissecting the Signaling Mechanisms Underlying Recognition and Preference of Food Odors
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DOI：
10.1523/jneurosci.0012-14.2014
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发表时间：
2014-07-09
影响因子：
5.3
通讯作者：
Zhang, Yun
中科院分区：
文献类型：
--
作者：
Harris, Gareth;Shen, Yu;Zhang, Yun
食物对于生存至关重要。许多动物，包括线虫秀丽隐杆线虫，使用感觉运动系统来检测和定位首选食物源。然而，人们对食物选择行为背后的信号机制知之甚少。在这里，我们描述了调节线虫不同食物气味之间的识别和偏好的分子信号传导。我们发现主要的嗅觉感觉神经元 AWB 和 AWC 在这种行为中发挥着重要作用。识别食物气味需要典型的 G α 蛋白以及鸟苷酸环化酶和 cGMP 门控通道。食物气味诱发的信号通过来自 AWC 的谷氨酸能神经传递以及 AMPA 和红藻氨酸样谷氨酸受体亚基进行传递。相比之下，需要肽能信号传导来产生不同食物气味之间的偏好，但对于气味识别来说却是可有可无的。我们证明这种调节是通过 AWB 中产生的神经肽 NLP-9 和 AWC 中产生的神经肽 NLP-1 实现的，神经肽 NLP-9 与其假定的受体 NPR-18 一起作用。此外，另一组感觉神经元抑制食物气味偏好。这些机械逻辑与之前绘制的食物气味偏好背后的神经回路一起，提供了一个连接感觉反应、转导和下游受体的功能网络，以处理复杂的嗅觉信息并生成生存所需的适当行为决策。
Food is critical for survival. Many animals, including the nematode Caenorhabditis elegans, use sensorimotor systems to detect and locate preferred food sources. However, the signaling mechanisms underlying food-choice behaviors are poorly understood. Here, we characterize the molecular signaling that regulates recognition and preference between different food odors in C. elegans. We show that the major olfactory sensory neurons, AWB and AWC, play essential roles in this behavior. A canonical G alpha-protein, together with guanylate cyclases and cGMP-gated channels, is needed for the recognition of food odors. The food-odor-evoked signal is transmitted via glutamatergic neurotransmission from AWC and through AMPA and kainate-like glutamate receptor subunits. In contrast, peptidergic signaling is required to generate preference between different food odors while being dispensable for the recognition of the odors. We show that this regulation is achieved by the neuropeptide NLP-9 produced in AWB, which acts with its putative receptor NPR-18, and by the neuropeptide NLP-1 produced in AWC. In addition, another set of sensory neurons inhibits food-odor preference. These mechanistic logics, together with a previously mapped neural circuit underlying food-odor preference, provide a functional network linking sensory response, transduction, and downstream receptors to process complex olfactory information and generate the appropriate behavioral decision essential for survival.