Regulation of distinct attractive and aversive mechanisms mediating benzaldehyde chemotaxis in Caenorhabditis elegans
Regulation of distinct attractive and aversive mechanisms mediating benzaldehyde chemotaxis in Caenorhabditis elegans
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DOI：
10.1101/lm.36501
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发表时间：
2001-05-01
影响因子：
2
通讯作者：
van der Kooy, D
中科院分区：
文献类型：
--
作者：
Nuttley, WM;Harbinder, S;van der Kooy, D
线虫的嗅觉介导的趋化性为研究信息处理的生物学机制提供了一个相对简单的系统。对100%苯甲醛的趋化反应的动力学分析表明，最初的诱人反应之后是对气味的强烈厌恶。我们发现，这种行为是由两条基因上可分离的吸引和厌恶调节反应通路来调节的。最初，这种吸引主导了行为，但随着时间的延长，习惯导致了行为的改变，以至于气味变得令人厌恶。这种嗅觉习惯化很容易丧失习惯性，从而重新建立起对气味的诱人反应。对推测的嗅觉适应突变体ADP-1(Ky20)的重新检查表明，在该品系中观察到的表型是由于对去习服刺激的超敏感，而不是对气味本身的适应缺陷。建立了一种改良的苯甲醛趋化试验，并用于分离一种具有特定习化动力学缺陷的突变体，该缺陷表现为吸引反应的持久性。
Olfactory-mediated chemotaxis in nematodes provides a relatively simple system to study biological mechanisms of information processing. Analysis of the kinetics of chemotaxis in response to 100% benzaldehyde revealed an initial attractive response that is followed by a strong aversion to the odorant. We show that this behavior is mediated by two genetically separable attraction and aversion-mediating response pathways. The attraction initially dominates behavior but with prolonged exposure habituation leads to a behavioral change, such that the odorant becomes repulsive. This olfactory habituation is susceptible to dishabituation, thereby re-establishing the attractive response to the odorant. Re-examination of the putative olfactory adaptation mutant adp-1(ky20) revealed that the phenotype observed in this line is due to a supersensitivity to a dishabituating stimulus, rather than a defect in the adaptation to odorants per se. A modified benzaldehyde chemotaxis assay was developed and used for the isolation of a mutant with a specific defect in habituation kinetics, expressed as a persistence of the attractive response.