Systematic Search for the Genes that Program Sex Behavior in Caenorhabditis elegans

我们已经着手分离线虫性行为缺陷的突变体。线虫的him-5突变体在其后代中产生高频率的雄性。plg-1突变体雄性在精子移植后在雌雄同体的外阴周围沉积存款凝胶状物质（称为塞子）。用诱变剂处理双突变体him-5 plg-1，并分离出交配缺陷突变体，即那些不能存款塞子的突变体。我们分离出39个这样的突变体。秀丽隐杆线虫雄性的交配行为包括四个步骤：“接触反应”、“转向”、“外阴定位”和“刺入”。在分离的突变体中，14个有缺陷的接触，23个有缺陷的转向，和5个缺陷的外阴位置。其中一些在多个步骤中存在缺陷。其中20个突变体的尾部有形态异常，这对雄性交配行为很重要。雄性的尾巴有9对感觉器官，称为鳍条。在突变体中观察到的异常包括射线融合和射线缺失。六个突变体似乎有缺陷的延伸和/或收缩的骨针，这是重要的精子转移。在11个没有明显形态学缺陷的突变体中，用荧光染料DiO染色显示感觉神经元的缺失。本研究中分离的突变体将有助于阐明雄性特异性结构和功能发育的遗传控制。

We have undertaken to isolate mutants defective in sex behavior in the nematode C.elegans. The him-5 mutant of C.elegans gives rise to high frequency of males in its offsprings. The plg-1 mutant males deposit gelatinous material (called plug) around the vulva of hermaphrodites after sperm transfer. Double mutant him-5 plg-1 was treated with mutagen and mating-deficient mutants were isolated as those that fail to deposit plug. We isolated 39 such mutants. The mating behavior of C.elegans males consists of four steps : "response to contact", "turning", "vulva location" and "spicule insertion". Among the mutants isolated, 14 had defect in response to contact, 23 had defect in turning, and 5 had defect in vulva location. Some of them had defects in multiple steps. Twenty of the mutants had morphological abnormalities in the tail, which is important for the male mating behavior. Male tail has 9 pairs of sensory organs called rays. The abnormalities observed in the mutants include fusion of rays and deletion of rays. Six mutants seemed to have defects in extension and/or retraction of their spicules, which are important for sperm transfer. Abnormalities in the sensory neurons were revealed by staining with fluorescent dye DiO in 11 of the mutants without gross morphological defects. The mutants isolated in this study will be useful in elucidating the genetic control of the development of male-specific structure and function.