Temperature representation in the Drosophila brain.
Temperature representation in the Drosophila brain.
复制标题
果蝇大脑中的温度表示。
DOI：
10.1038/nature14284
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发表时间：
2015-03-19
期刊：
影响因子：
64.8
通讯作者：
Gallio M
中科院分区：
文献类型：
--
作者：
Frank DD;Jouandet GC;Kearney PJ;Macpherson LJ;Gallio M
在果蝇中，专用受体可以检测到周围温度的快速变化，从而在大脑中形成简单的冷热感觉图。然而，果蝇对温度表现出许多复杂的先天和后天反应，这表明它们能够从这个简单的输入中提取一系列信息。在这里，我们定义了果蝇大脑中温度表示的解剖学和生理学库。首先，我们使用光标记策略来追踪将外围热感觉信息传递到高级大脑中心的连接，并表明它们主要集中在三个目标区域：蘑菇体、侧角（众所周知的感觉处理中心）和后外侧原大脑，我们现在将其定义为热感觉表征的主要部位。然后，利用体内钙成像，我们描述了由热或冷刺激选择性激活的热感觉投射神经元。快速适应的神经元表现出短暂的“开”和“关”反应，并能很好地跟踪快速的温度变化，而慢适应的细胞反应可以更好地反映简单热变化的幅度。出乎意料的是，我们还发现了一群对加热和冷却都有反应的“广泛调整”的细胞，并表明它们是在简单的二选温度偏好测定中避免热和冷的正常行为所必需的。总而言之，我们的结果揭示了果蝇大脑中对温度的神经反应的协调集合，证明了广泛调节的热线有助于快速回避行为，并说明了如何从单个突触站的简单肾小球图中提取刺激质量、时间结构和强度。
In Drosophila, rapid temperature changes are detected at the periphery by dedicated receptors forming a simple sensory map for hot and cold in the brain. However, flies show a host of complex innate and learned responses to temperature, indicating that they are able to extract a range of information from this simple input. Here, we define the anatomical and physiological repertoire for temperature representation in the Drosophila brain. First, we use a photolabeling strategy to trace the connections that relay peripheral thermosensory information to higher brain centers, and show that they largely converge onto three target regions: the Mushroom Body, Lateral Horn (well-known centers for sensory processing) and the Posterior Lateral Protocerebrum, a region we now define as a major site of thermosensory representation. Then, using in vivo calcium imaging, we describe the thermosensory projection neurons selectively activated by hot or cold stimuli. Fast-adapting neurons display transient “ON” and “OFF” responses and track rapid temperature shifts remarkably well, while slow-adapting cell responses better reflect the magnitude of simple thermal changes. Unexpectedly, we also find a population of ‘broadly-tuned’ cells that respond to both heating and cooling, and show that they are required for normal behavioral avoidance of both hot and cold in a simple 2-choice temperature preference assay. Taken together, our results uncover a coordinated ensemble of neural responses to temperature in the fly brain, demonstrate that a broadly tuned thermal-line contributes to rapid avoidance behavior, and illustrate how stimulus quality, temporal structure, and intensity can be extracted from a simple glomerular map at a single synaptic station.