Olfactory receptor neurons use gain control and complementary kinetics to encode intermittent odorant stimuli
Olfactory receptor neurons use gain control and complementary kinetics to encode intermittent odorant stimuli
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DOI：
10.7554/elife.27670
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发表时间：
2017-06-28
期刊：
影响因子：
7.7
通讯作者：
Emonet, Thierry
中科院分区：
文献类型：
--
作者：
Gorur-Shandilya, Srinivas;Demir, Mahmut;Emonet, Thierry
昆虫通过导航气味羽流来寻找食物和配偶，这些气味羽流可能是高度间歇性的，其强度和持续时间在数量级上迅速变化。关于嗅觉对脉冲和脚步的反应，我们已经知道很多了，但是嗅觉受体神经元（ORN）如何检测自然刺激的强度和时间仍然不清楚，在这种情况下，信号中没有尺度使得检测成为一项艰巨的嗅觉任务。通过刺激果蝇ORN在体内与自然和高斯刺激，我们表明，ORN适应刺激的均值和方差，适应和饱和度有助于自然的感觉。均值依赖性增益控制遵循韦伯-费希纳关系，主要发生在气味转导，而方差依赖性增益控制发生在转导和尖峰。转导和穗代具有互补的动力学特性，共同保存的时间气味遇到ORN穗，无论强度。这种尺度不变性在气味羽流导航过程中可能是至关重要的。
Insects find food and mates by navigating odorant plumes that can be highly intermittent, with intensities and durations that vary rapidly over orders of magnitude. Much is known about olfactory responses to pulses and steps, but it remains unclear how olfactory receptor neurons (ORNs) detect the intensity and timing of natural stimuli, where the absence of scale in the signal makes detection a formidable olfactory task. By stimulating Drosophila ORNs in vivo with naturalistic and Gaussian stimuli, we show that ORNs adapt to stimulus mean and variance, and that adaptation and saturation contribute to naturalistic sensing. Mean-dependent gain control followed the Weber-Fechner relation and occurred primarily at odor transduction, while variance dependent gain control occurred at both transduction and spiking. Transduction and spike generation possessed complementary kinetic properties, that together preserved the timing of odorant encounters in ORN spiking, regardless of intensity. Such scale-invariance could be critical during odor plume navigation.