A circuit for navigation in Caenorhabditis elegans
A circuit for navigation in Caenorhabditis elegans
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DOI：
10.1073/pnas.0409009101
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发表时间：
2005-03-01
影响因子：
11.1
通讯作者：
Bargmann, CI
中科院分区：
文献类型：
--
作者：
Gray, JM;Hill, JJ;Bargmann, CI
秀丽隐杆线虫通过偶尔的转向和逆转来中断其向前运动，从而探索其环境。转向和反转以稳定的频率但不规则的间隔发生，产生概率探索行为。在这里，我们剖析了在不同条件下的探索行为中，单个感觉神经元，中间神经元和运动神经元的作用。动物从细菌食物中移除后，它们开始局部搜索行为，包括AWC嗅觉神经元、ASK味觉神经元和AIB中间神经元触发的反转和深Ω形转弯。在接下来的30分钟内，动物随着反转而分散，并且omega转向被ASI味觉神经元和AIY中间神经元抑制。AIB和AN下游的中间神经元和运动神经元编码反转和转动频率、振幅和方向性的特定方面。SMD运动神经元帮助编码ω转弯的陡峭幅度，RIV运动神经元指定反转后转弯的腹侧偏置，SMB运动神经元设置正弦运动的幅度。这些感觉神经元、中间神经元和运动神经元中的许多也涉及趋化性和趋热性。因此，该电路可以表示用于多个导航行为的公共基板。
Caenorhabditis elegans explores its environment by interrupting its forward movement with occasional turns and reversals. Turns and reversals occur at stable frequencies but irregular intervals, producing probabilistic exploratory behaviors. Here we dissect the roles of individual sensory neurons, interneurons, and motor neurons in exploratory behaviors under different conditions. After animals are removed from bacterial food, they initiate a local search behavior consisting of reversals and deep omega-shaped turns triggered by AWC olfactory neurons, ASK gustatory neurons, and AIB interneurons. Over the following 30 min, the animals disperse as reversals and omega turns are suppressed by ASI gustatory neurons and AIY interneurons. Interneurons and motor neurons downstream of AIB and AN encode specific aspects of reversal and turn frequency, amplitude, and directionality. SMD motor neurons help encode the steep amplitude of omega turns, RIV motor neurons specify the ventral bias of turns that follow a reversal, and SMB motor neurons set the amplitude of sinusoidal movement. Many of these sensory neurons, interneurons, and motor neurons are also implicated in chemotaxis and thermotaxis. Thus, this circuit may represent a common substrate for multiple navigation behaviors.