Avery L, Horvitz H R
Department of Biology, Massachusetts Institute of Technology, Cambridge. 02139.
Neuron. 1989 Oct;3(4):473-85. doi: 10.1016/0896-6273(89)90206-7.
Using a laser microbeam to kill specific subsets of the pharyngeal nervous system of C. elegans, we found that feeding was accomplished by two separately controlled muscle motions, isthmus peristalsis and pumping. The single neuron M4 was necessary and sufficient for isthmus peristalsis. The MC neurons were necessary for normal stimulation of pumping in response to food, but pumping continued and was functional in MC- worms. The remaining 12 neuron types were also unnecessary for functional pumping. No operation we did, including destruction of the entire pharyngeal nervous system, abolished pumping altogether. When we killed all pharyngeal neurons except M4, the worms were viable and fertile, although retarded and starved. Since feeding is one of the few known essential actions controlled by the nervous system, we suggest that most of the C. elegans nervous system is dispensable in hermaphrodites under laboratory conditions. This may explain the ease with which nervous system mutants are isolated and handled in C. elegans.
利用激光微束杀死秀丽隐杆线虫咽神经系统的特定亚群，我们发现摄食是由两种分别控制的肌肉运动完成的，即峡部蠕动和抽吸。单个神经元M4对峡部蠕动是必需且充分的。MC神经元对于正常情况下响应食物刺激进行抽吸是必需的，但在MC缺陷型线虫中，抽吸仍会继续且具有功能。其余12种神经元类型对于功能性抽吸也不是必需的。我们所做的任何操作，包括破坏整个咽神经系统，都没有完全消除抽吸。当我们杀死除M4之外的所有咽神经元时，线虫虽然发育迟缓且饥饿，但仍可存活并繁殖。由于摄食是已知的少数由神经系统控制的基本行为之一，我们认为在实验室条件下，秀丽隐杆线虫的大多数神经系统对于雌雄同体线虫来说是可有可无的。这可能解释了在秀丽隐杆线虫中分离和处理神经系统突变体为何如此容易。
