Excitatory interactions between olfactory processing channels in the Drosophila antennal lobe
Excitatory interactions between olfactory processing channels in the Drosophila antennal lobe
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DOI：
10.1016/j.neuron.2007.03.010
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发表时间：
2007-04-05
期刊：
影响因子：
16.2
通讯作者：
Wilson, Rachel I.
中科院分区：
文献类型：
--
作者：
Olsen, Shawn R.;Bhandawat, Vikas;Wilson, Rachel I.
每个气味受体基因定义了一种独特的嗅觉感受器神经元(ORN)和相应类型的二级神经元。因为每种气味可以激活多种ORN类型，所以信息最终必须跨这些处理渠道进行整合，以形成统一的感知。在这里，我们证明，在果蝇中，整合始于二级投射神经元(PNS)水平。我们从基因上沉默了所有正常表达特定气味受体的鸟巢，并发现与沉默的肾小球的突触后PNS从其他肾小球接收到大量的侧向兴奋性输入。从基因上将气味诱发的ORN输入限制在一个肾小球上，揭示了大多数突触后到其他肾小球的PNS接受来自活跃的单一ORN类型的间接兴奋性输入。已识别的肾小球之间的侧向连接强度不同，这种连接模式在果蝇中是刻板印象的。因此，一个密集的侧向连接网络在嗅觉处理流的第一个脑区的通道之间分配气味诱发的兴奋。
Each odorant receptor gene defines a unique type of olfactory receptor neuron (ORN) and a corresponding type of second-order neuron. Because each odor can activate multiple ORN types, information must ultimately be integrated across these processing channels to form a unified percept. Here, we show that, in Drosophila, integration begins at the level of second-order projection neurons (PNs). We genetically silence all the ORNs that normally express a particular odorant receptor and find that PNs postsynaptic to the silent glomerulus receive substantial lateral excitatory input from other glomeruli. Genetically confining odor-evoked ORN input to just one glomerulus reveals that most PNs postsynaptic to other glomeruli receive indirect excitatory input from the single ORN type that is active. Lateral connections between identified glomeruli vary in strength, and this pattern of connections is stereotyped across flies. Thus, a dense network of lateral connections distributes odor-evoked excitation between channels in the first brain region of the olfactory processing stream.