DROSOPHILA OVARIAN TUMOR GENE AND OOGENESIS

果蝇卵巢肿瘤基因和卵子发生

• 批准号: 2444865
• 负责人: Lillie L. SEARLES
• 金额: $ 14.85万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-07-01 至 1999-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2444865
• 关键词: Drosophilidae; RNA binding protein; alleles; cell differentiation; cell growth regulation; cytogenetics; gel electrophoresis; gene expression; gene interaction; gene mutation; genetic regulation; genetic translation; immunoprecipitation; messenger RNA; molecular cloning; molecular site; oogenesis; phenotype; sex determination; tumor suppressor genes

DESCRIPTION: Genetic and molecular studies have shown that the Drosophila ovarian tumor gene functions at several key points during oogenesis. Mutations in this gene can be roughly grouped into three classes on the basis of the severity of the phenotype. The most severe mutants fall into the quiescent class (QUI). The ovaries of these mutants appear to lack germ cells altogether, and consist of small empty sheaths of somatic tissue.The second phenotypic class, for which locus was originally named, are the tumorous ovary alleles (ONC). In these mutants germ line cells are present; however, oogenesis is arrested at an early step and the ovary becomes populated with many, often hundreds, of small undifferentiated germ cells. The third phenotypic class, DIF, is least severe. The early steps in egg chamber formation often proceed almost normally in this class of mutants; however some chambers are formed which lack the oocyte or have abnormal numbers of nurse cells. Other chambers appear almost wild type, but at late stages of oogenesis the nurse cells in these chambers fail to dump their contents into the oocyte. The range of phenotypic defects in the different classes is most easily explained by a model which postulates that increasing levels otu function are required as oogenesis proceeds. Other hints as to the possible function of the otu product come from the observation that several of the ONC alleles show defects in the expression of Sex-lethal protein and the processing of Sxl mRNAs. Consistent with the idea that otu is required for the proper expression of Sxl in the female germ line is the finding that ONC mutants can be partially rescued by a constitutive Sxl allele. However, facilitating Sxl expression is not only function of otu since the consitutive Sxl allele has no effect on the phenotypes of the QUI or DIF otu mutants.

描述：遗传和分子研究表明 果蝇卵巢肿瘤基因在几个关键点起作用 卵子发生。该基因中的突变可以大致分为三个 基于表型的严重性。最严重的 突变体落入静态类（qui）。这些的卵巢 突变体似乎完全缺乏生殖细胞，由小空组成 躯体组织的鞘。第二个表型类别 最初命名为肿瘤卵巢等位基因（ONC）。在这些 存在突变的种系细胞；但是，卵子发生在 早期的一步和卵巢被许多，通常数百个人口 小的未分化生殖细胞。第三个表型类，dif， 最不重要。卵室形成的早期步骤经常继续 几乎通常在这类突变体中；但是有些房间是 缺乏卵母细胞或具有异常数量的护士细胞的形成。 其他腔室几乎看起来几乎是野生型，但在卵子发生的后期 这些房间中的护士牢房未能将其内容物倒入 卵母细胞。不同类别中表型缺陷的范围最多 很容易解释一个模型，该模型假定otu水平增加了 随着卵子发生的进行，需要功能。其他提示 OTU产品的可能功能来自于观察到 几个ONC等位基因在性爱表达中显示出缺陷 蛋白质和SXL mRNA的加工。与这样的想法一致 OTU是在雌性种系中正确表达SXL所必需的 是否发现可以通过 本构SXL等位基因。但是，促进SXL表达不是 只有OTU的功能，因为固定的SXL等位基因对 qui或dif otu突变体的表型。