Mutations in Two Independent Pathways Are Sufficient to Create Hermaphroditic Nematodes
Mutations in Two Independent Pathways Are Sufficient to Create Hermaphroditic Nematodes
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DOI：
10.1126/science.1176013
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发表时间：
2009-11-13
期刊：
影响因子：
56.9
通讯作者：
Ellis, Ronald E.
中科院分区：
文献类型：
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作者：
Baldi, Chris;Cho, Soochin;Ellis, Ronald E.
尽管线虫秀丽隐杆线虫产生自体受精的雌雄同体，但它是雄性/雌性物种的后代，因此雌雄同体为新性状的起源提供了一个模型。在只有雄性和雌性的相关物种 C. remanei 中，通过 RNA 干扰降低 tra-2 的活性，产生了 XX 动物，它们既能产生精子也能产生卵母细胞，但如果不添加雄性精液，它们的精子细胞就无法激活。然而，通过降低 tra-2 和 swm-1（一种调节线虫精子激活的基因）的表达，我们生产了具有自体受精活性精子的 XX 动物。因此，秀丽隐杆线虫的雌雄同体进化可能需要两个步骤：导致XX精子发生的性别决定途径的突变和允许这些精子细胞自我激活的突变。
Although the nematode Caenorhabditis elegans produces self-fertile hermaphrodites, it descended from a male/female species, so hermaphroditism provides a model for the origin of novel traits. In the related species C. remanei, which has only male and female sexes, lowering the activity of tra-2 by RNA interference created XX animals that made spermatids as well as oocytes, but their spermatids could not activate without the addition of male seminal fluid. However, by lowering the expression of both tra-2 and swm-1, a gene that regulates sperm activation in C. elegans, we produced XX animals with active sperm that were self-fertile. Thus, the evolution of hermaphroditism in Caenorhabditis probably required two steps: a mutation in the sex-determination pathway that caused XX spermatogenesis and a mutation that allowed these spermatids to self-activate.