Neural mechanism of spatio-chromatic opponency in the Drosophila amacrine neurons.
Neural mechanism of spatio-chromatic opponency in the Drosophila amacrine neurons.
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果蝇无长突神经元空间色彩对抗的神经机制。
DOI：
10.1016/j.cub.2021.04.068
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
Lee,Chi-Hon
中科院分区：
文献类型：
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作者：
Li,Yan;Chen,Pei-Ju;Lin,Tzu-Yang;Ting,Chun-Yuan;Muthuirulan,Pushpanathan;Pursley,Randall;Ilić,Marko;Pirih,Primož;Drews,MichaelS;Menon,KaushikiP;Zinn,KaiG;Pohida,Thomas;Borst,Alexander;Lee,Chi-Hon
视觉动物探测光强度和波长组成的空间变化。对手编码是减少信息冗余的常用策略。在脊椎动物中已经发现了同时具有空间和光谱对抗性的神经元，但在昆虫中还没有发现。果蝇无长突神经元Dm8最近被报道具有颜色对抗性。在这里，我们证明了Dm8表现出空间-色度对抗性。来自紫外线感应R7的直接输入和来自宽带受体R1-R6通过TM3和MI1的间接输入的拮抗汇聚足以赋予Dm8‘S UV/VIS(紫外线/可见光)对抗能力。使用高分辨率单色刺激，我们显示淡色和黄色的Dm8亚型继承了视网膜马赛克特征，具有明显的光谱调谐特性。利用二维白噪声刺激和反向相关分析，我们发现Dm8的UV感受场(RF)具有中心抑制/环绕激发结构。在没有UV感受器R7输入的情况下，由于来自宽带光感受器R1-R6的兴奋性输入，RF的极性反转。利用一种基于内源性神经递质受体的新的SynGRASP方法，我们发现相邻的Dm8形成了由谷氨酸门控氯通道GluClα介导的相互抑制连接，这对Dm8的S空间对抗和动物的趋光行为都是必不可少的。我们的研究表明，空间-色度对抗性可能出现在视觉的早期阶段，这表明无脊椎动物和脊椎动物都存在一种共同的信息处理策略。
Visual animals detect spatial variations of light intensity and wavelength composition. Opponent coding is a common strategy for reducing information redundancy. Neurons equipped with both spatial and spectral opponency have been identified in vertebrates but not yet in insects. TheDrosophilaamacrine neuron Dm8 was recently reported to show color opponency. Here, we demonstrate Dm8 exhibits spatio-chromatic opponency. Antagonistic convergence of the direct input from the UV-sensing R7s and indirect input from the broadband receptors R1–R6 through Tm3 and Mi1 is sufficient to confer Dm8's UV/Vis (ultraviolet/visible light) opponency. Using high resolution monochromatic stimuli, we show the pale and yellow subtypes of Dm8s, inheriting retinal mosaic characteristics, have distinct spectral tuning properties. Using 2D white-noise stimulus and reverse correlation analysis, we found that the UV receptive field (RF) of Dm8 has a center-inhibition/surround-excitation structure. In the absence of UV-sensing R7 inputs, the polarity of the RF is inverted owing to the excitatory input from the broadband photoreceptors R1–R6. Using a new synGRASP method based on endogenous neurotransmitter receptors, we show that neighboring Dm8s form mutual inhibitory connections mediated by the glutamate-gated chloride channel GluClα, which is essential for both Dm8's spatial opponency and animals' phototactic behavior. Our study shows spatio-chromatic opponency could arise in the early visual stage, suggesting a common information processing strategy in both invertebrates and vertebrates.