The dpy-30 gene encodes an essential component of the Caenorhabditis elegans dosage compensation machinery.
The dpy-30 gene encodes an essential component of the Caenorhabditis elegans dosage compensation machinery.
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DOI：
10.1093/genetics/137.4.999
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发表时间：
1994-08
期刊：
影响因子：
3.3
通讯作者：
D. Hsu;B. Meyer
中科院分区：
文献类型：
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作者：
D. Hsu;B. Meyer
调节秀丽隐杆线虫中X染色体表达的需要是由于主要的性别决定信号X/A比率（X染色体与常染色体组的比率），其指导1X@A动物发育为雄性和2X/2A动物发育为雌雄同体。C.线虫具有一种剂量补偿机制，尽管两性在X染色体剂量上存在差异，但该机制使两性之间的X染色体表达相等。先前的遗传分析导致四个常染色体基因，dpy-21，dpy-26，dpy-27和dpy-28的鉴定，其产物在XX动物中对于适当的剂量补偿是必需的，但不是性别决定。我们报告的识别和表征的dpy-30，剂量补偿机制的重要组成部分。dpy-30中假定的无效突变破坏剂量补偿，并导致严重的母体效应，XX特异性致死性。dpy-30致死性的罕见幸存者是矮胖的，并以高于野生型的水平表达其X连锁基因。这些dpy-30突变体表型表面上类似于dpy-26，dpy-27和dpy-28突变引起的表型;然而，详细的表型分析揭示了区分dpy-30与这些基因的重要差异。与由其他dpy基因突变引起的XX特异性致死性相反，由dpy-30突变引起的XX特异性致死性是完全渗透性和温度敏感性的。此外，与其他基因不同，dpy-30是XO动物正常发育所必需的。虽然dpy-30突变不会显著影响XO动物的生存能力，但它们确实会导致它们发育延迟并具有许多形态和行为异常。最后，dpy-30突变可以显着影响性别身份模糊的动物的性命运的选择，尽管对野生型动物的性表型没有明显的影响。巧合的是，根据遗传背景，dpy-30突变导致雄性化或雌性化，从而揭示了性别决定和剂量补偿过程之间复杂的调节关系。dpy-30突变引起的新表型表明，除了在剂量补偿过程中起作用外，dpy-30可能在XX和XO动物的发育中发挥更普遍的作用。
The need to regulate X chromosome expression in Caenorhabditis elegans arises as a consequence of the primary sex-determining signal, the X/A ratio (the ratio of X chromosomes to sets of autosomes), which directs 1X@A animals to develop as males and 2X/2A animals to develop as hermaphrodites. C. elegans possesses a dosage compensation mechanism that equalizes X chromosome expression between the two sexes despite their disparity in X chromosome dosage. Previous genetic analysis led to the identification of four autosomal genes, dpy-21, dpy-26, dpy-27 and dpy-28, whose products are essential in XX animals for proper dosage compensation, but not for sex determination. We report the identification and characterization of dpy-30, an essential component of the dosage compensation machinery. Putative null mutations in dpy-30 disrupt dosage compensation and cause a severe maternal-effect, XX-specific lethality. Rare survivors of the dpy-30 lethality are dumpy and express their X-linked genes at higher than wild-type levels. These dpy-30 mutant phenotypes superficially resemble those caused by mutations in dpy-26, dpy-27 and dpy-28; however, detailed phenotypic analysis reveals important differences that distinguish dpy-30 from these genes. In contrast to the XX-specific lethality caused by mutations in the other dpy genes, the XX-specific lethality caused by dpy-30 mutations is completely penetrant and temperature sensitive. In addition, unlike the other genes, dpy-30 is required for the normal development of XO animals. Although dpy-30 mutations do not significantly affect the viability of XO animals, they do cause them to be developmentally delayed and to possess numerous morphological and behavioral abnormalities. Finally, dpy-30 mutations can dramatically influence the choice of sexual fate in animals with an ambiguous sexual identity, despite having no apparent effect on the sexual phenotype of otherwise wild-type animals. Paradoxically, depending on the genetic background, dpy-30 mutations cause either masculinization or feminization, thus revealing the complex regulatory relationship between the sex determination and dosage compensation processes. The novel phenotypes caused by dpy-30 mutations suggest that in addition to acting in the dosage compensation process, dpy-30 may play a more general role in the development of both XX and XO animals.