Molecular Genetics of a New Tumor Suppressor Gene in Drosophila

果蝇新抑癌基因的分子遗传学

• 批准号: 9206096
• 负责人: Peter Bryant
• 金额: $ 39万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-08-01 至 1996-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9206096&HistoricalAwards=false
• 关键词: Molecular; Genetics; New; Tumor; Suppressor

We propose a molecular genetic analysis of a newly discovered tumor-suppressor gene (warts,abb.wts) in Drosophila. The gene is identified by the tumorous phenotype of mitotic-recombination clones that are homozygous for small chromosome deficiencies of the wts gene. Absence of the wts gene from imaginal disc cells causes excess cell proliferation, causes clone rounding presumably by interfering with control of oriented cell divisions, and allows cuticle to be secreted between cells as well as over their apical surfaces. The wts gene is known, from cytogenetic mapping, to be present in DNA that has already been cloned. We will isolate new mutations in wts and other unidentified tumor suppressor genes using a new method for revealing the homozygous phenotype of recessive mutations in mitotic recombination clones. We will identify the transcription unit corresponding to wts in the cloned DNA by mapping deficiency breakpoints and wts mutations at the DNA level. We will isolate cDNAs corresponding to wts and determine their nucleotide sequence in order to predict the amino acid sequence and possible function of the gene product. Antibodies will be raised against a fusion gene product made in bacteria, and the antibodies will be used to localize the gene product at both light and electron microscopic levels. We will mark wts clones in the undifferentiated imaginal disc in order to further examine the effects of the mutation on clone growth and on the distribution of cytoskeletal and cell-surface proteins. %%% The identification and characterization of novel tumor-suppressor genes in this simple model system of the fruit fly may lead to the identification of new tumor-suppressor genes in man.

我们提出了一个新发现的肿瘤抑制基因（疣，abb.wts）在果蝇的分子遗传学分析。该基因是通过有丝分裂重组克隆的肿瘤表型鉴定的，该克隆是纯合的，用于wts基因的小染色体缺陷。wts基因的缺失会导致细胞过度增殖，可能是由于干扰了细胞定向分裂的控制而导致克隆圆缩，并允许细胞间和细胞顶表面分泌角质层。从细胞遗传学定位来看，wts基因存在于已经克隆的DNA中。我们将利用一种揭示有丝分裂重组克隆中隐性突变纯合表型的新方法分离wts和其他未识别的肿瘤抑制基因的新突变。我们将通过在DNA水平上定位缺陷断点和wts突变来确定克隆DNA中与wts相对应的转录单元。我们将分离wts对应的cdna并确定其核苷酸序列，以预测基因产物的氨基酸序列和可能的功能。针对细菌中产生的融合基因产物产生抗体，抗体将用于在光和电子显微镜水平上定位基因产物。我们将在未分化的影像盘上标记wts克隆，以便进一步检查突变对克隆生长和细胞骨架和细胞表面蛋白分布的影响。在果蝇这个简单的模型系统中发现和鉴定新的肿瘤抑制基因可能会导致在人类中发现新的肿瘤抑制基因。