Novel neuronal network underlying Drosophila olfactory learning and memory

果蝇嗅觉厌恶条件反射是研究记忆形成的分子和神经元机制的有力模型系统。我设计了一种简单、低成本的半自动调节装置，它可以通过计算控制气味和震动的传递。该系统适用于研究嗅觉记忆的形成和检查条件参数的细节水平，这是手工设备无法实现的。为了确定果蝇嗅觉记忆的新神经网络，我进行了Gal4增强陷阱筛选，并确定了一对神经支配于嗅觉记忆编码的蘑菇体（MB）上的神经元。经鉴定的神经元（我们称之为PMO神经元）的突触传递瞬间沉默，shibiire ^<ts>表明这些神经元特异性参与（3小时）嗅觉厌恶记忆后期的形成。嗅觉记忆的早期阶段（1小时）不需要它们。这些数据表明，在MB的下游存在一个用于记忆巩固的神经元回路。

Drosophila olfactory aversive conditioning has served as a powerful model system with which to elucidate the molecular and neuronal mechanisms underlying memory formation. I have devised a simple, low-cost semi-automated conditioning apparatus that computationally controls the delivery of odor and shock. The system is applicable to the study of olfactory memory formation and to the examination of conditioning parameters at a level of detail not practical with a manual apparatus.To identify a novel neuronal network underlying Drosophila olfactory memory, I conducted a Gal4 enhancer-trap screening and identified a pair of neurons innervating onto the mushroom body (MB) in which olfactory memory is encoded. Transient silencing of synaptic transmissions from identified neurons, we call them PMO neurons, with Shibire^<ts> showed that these neurons are specifically involved in the formation of the late stage of (3 hr) olfactory aversive memory. They were not required for the early stage (1 hr) of olfactory memory. These data imply the presence of a neuronal circuit for memory consolidation that function downstream of the MB.