Effects of Ionizing Radiation on Locomotory Behavior and Mechanosensation in Caenorhabditis elegans
Effects of Ionizing Radiation on Locomotory Behavior and Mechanosensation in Caenorhabditis elegans
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DOI：
10.1269/jrr.08087
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发表时间：
2009-03-01
影响因子：
2
通讯作者：
Kobayashi, Yasuhiko
中科院分区：
文献类型：
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作者：
Suzuki, Michiyo;Sakashita, Tetsuya;Kobayashi, Yasuhiko
动物的运动行为(运动)和机械感觉是至关重要的。我们研究了电离辐射(IR)对模式生物秀丽线虫的运动行为和机械感觉的影响。线虫中的细菌机械感觉诱导多巴胺介导的在细菌(食物)存在的情况下运动减慢，称为基本减慢反应。我们以前曾报道过，在缺乏食物的情况下，IR诱导的运动率降低。在目前的研究中，我们观察到类似的IR导致CAT-2突变体的运动速度降低，该突变体在细菌机械感觉方面存在缺陷。野生型动物在食物存在下的运动率的剂量反应模式相对平坦，但在CAT-2突变体中则不是。这表明，与线虫的细菌机械感觉有关的多巴胺系统可能对食物存在时的运动速度具有主导作用，从而掩盖了其他刺激的影响。此外，我们还发现，过氧化氢暴露的野生动物的行为反应与暴露于IR的动物相似。我们的发现表明，在没有食物的情况下，IR诱导的运动率下降是由一种不同于细菌机械感觉的途径介导的，至少部分是通过IR产生的过氧化氢。
Locomotory behavior (motility) and mechanosensation are of vital importance in animals. We examined the effects of ionizing radiation (IR) on locomotory behavior and mechanosensation using a model organism, the nematode Caenorhabditis elegans. Bacterial mechanosensation in C elegans induces the dopamine-mediated slowing of locomotion in the presence of bacteria (food), known as the basal slowing response. We previously reported an IR-induced reduction of locomotory rate in the absence of food. In the present study, we observed a similar IR-induced reduction of locomotory rate in the cat-2 mutant, which is defective in bacterial mechanosensation. The dose response pattern of the locomotory rate in the presence of food was relatively flat in wild-type animals, but not in cat-2 mutants. This suggests that the dopamine system, which is related to bacterial mechanosensation in C. elegans, might have a dominant effect on locomotory rate in the presence of food, which masks the effects of other stimuli. Moreover, we found that the behavioral responses of hydrogen peroxide-exposed wild-type animals are similar to those of IR-exposed animals. Our findings suggest that the IR-induced reduction of locomotory rate in the absence of food is mediated by a different pathway from that for bacterial mechanosensation, at least partially through IR-produced hydrogen peroxide.