mag-1, a homolog of Drosophila mago nashi regulates hermaphrodite germ-line sex determination in Caenorhabditis elegans
mag-1, a homolog of Drosophila mago nashi regulates hermaphrodite germ-line sex determination in Caenorhabditis elegans
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DOI：
10.1006/dbio.1999.9593
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发表时间：
2000-02-15
影响因子：
2.7
通讯作者：
Wood, WB
中科院分区：
文献类型：
--
作者：
Li, WQ;Boswell, R;Wood, WB
秀丽隐杆线虫基因mag-1可以在功能上替代其在果蝇中的同源物Mago nashi，并且预测其编码的蛋白质与Mago nashi具有80%的同一性和88%的相似性（P.A. Newmark等人，1997，Development 120，3197-3207）。我们已经使用RNA介导的干扰（RNAi）来分析在C.优美的我们在这里表明，mag-1（RNAi）导致雄性化的生殖系（MOG表型）在RNA注射雌雄同体，这表明mag-1参与雌雄同体生殖系性别决定。上位性分析表明，由mag-1（RNAi）引起的异位精子产生被fog-2、gld-1、fem-1、fem-2、fem-3和fog-1中的功能丧失（lf）突变阻止，所有这些突变都导致XX雌雄同体的生殖系女性化，但不被仅导致XO雄性生殖系女性化的her-1（lf）突变阻止。这些结果表明mag-1与fog，fem和gld基因相互作用，并且独立于her-1发挥作用。我们认为mag-1通常通过抑制一个或多个这些雄性化基因的功能来允许卵子发生，这些基因在第四幼虫阶段起作用，以促进两性生殖系中的瞬时精子产生。当Mog表型被fog-2（if）突变抑制时，mag-1（RNAi）也会导致注射RNA的交配雌雄同体后代胚胎的致死性，这表明mag-1在胚胎发生过程中起着重要作用。有缺陷的胚胎在形态发生过程中停滞，具有明显的伸长缺陷。JAM-1：：GFP报告基因定位于下皮细胞的边界，其分布模式显示在这些胚胎中下皮是无序的。mag-1基因在形态发生之前和期间的时间表达模式似乎与mag-1在胚胎皮下组织和伸长中的重要作用一致，（C）2000学术出版社。
The Caenorhabditis elegans gene mag-1 can substitute functionally for its homolog mago nashi in Drosophila and is predicted to encode a protein that exhibits 80% identity and 88% similarity to Mago nashi (P. A. Newmark et al., 1997, Development 120, 3197-3207). We have used RNA-mediated interference (RNAi) to analyze the phenotypic consequences of impairing mag-1 function in C. elegans. We show here that mag-1(RNAi) causes masculinization of the germ line (Mog phenotype) in RNA-injected hermaphrodites, suggesting that mag-1 is involved in hermaphrodite germ-line sex determination. Epistasis analysis shows that ectopic sperm production caused by mag-1(RNAi) is prevented by loss-of-function (lf) mutations in fog-2, gld-1, fem-1, fem-2 fem-3, and fog-1, all of which cause germ-line feminization in XX hermaphrodites, but not by a her-1(lf) mutation which causes germ-line feminization only in XO males. These results suggest that mag-1 interacts with the fog, fem, and gld genes and acts independently of her-1. We propose that mag-1 normally allows oogenesis by inhibiting function of one or more of these masculinizing genes, which act during the fourth larval stage to promote transient sperm production in the hermaphrodite germ line. When the Mog phenotype is suppressed by a fog-2(if) mutation, mag-1(RNAi) also causes lethality in the progeny embryos of RNA-injected, mated hermaphrodites, suggesting an essential role for mag-1 during embryogenesis. The defective embryos arrest during morphogenesis with an apparent elongation defect. The distribution pattern of a JAM-1::GFP reporter, which is localized to boundaries of hypodermal cells, shows that hypodermis is disorganized in these embryos. The temporal expression pattern of the mag-1 gene prior to and during morphogenesis appears to be consistent with an essential role of mag-1 in embryonic hypodermal organization and elongation, (C) 2000 Academic Press.