THE FMS ONCOGENE

逆转录病毒癌基因v-fms是通过基因重组获得的 丝状白血病病毒（FeLV）和原癌基因序列（c-fms）之间的关系 正常的猫细胞。 v-fms基因只在一种猫科动物中发现 肉瘤病毒（FeSV），编码一种未知的转化糖蛋白 功能 c-fms基因的产物还没有被鉴定出来， 它与病毒转化蛋白的关系已被阐明。 该提案描述了详细的特性的v-fms编码的 糖蛋白，定义了识别糖蛋白产物的第一步。 细胞原癌基因，并试图阐明这些蛋白质的作用， 恶性转化 使用最近确定的核苷酸 序列的生物活性克隆的FeSV DNA，我们建议放置 v-fms基因的定点突变 特别是，突变将 （i）v-fms基因的有限区域，其显示出乎意料的 与酪氨酸激酶基因家族的v-onc基因的同源性，以及与（ii） 信号序列被认为在亚细胞中起作用， 转化糖蛋白的定位。 转化活动 将通过DNA转染到培养的细胞上来测定改变的基因。 将使用显性选择标记共转染来分离 非转化变体，其编码产物将被生物化学地 与野生型转化基因相比。 感应 v-fms基因产物中的生化改变将与 蛋白质的拓扑结构及其转化活性。 并行 研究，c-fms基因的基因组和cDNA克隆将用于预测 其产品的主要结构，从而促进其 鉴定和表征。 之间的重组DNA分子 C-FMS和V-FMS将被准备好，以努力激活潜在的 细胞原癌基因的转化潜力。 预计 对v-fms编码的糖蛋白中的结构域的详细表征 在翻译后加工、细胞内转运和 转化将提供激活细胞的基础， 原癌基因并决定其功能。 后一项研究将 强调人c-fms原癌基因的结构和表达 及其在癌症中的潜在作用。

The retroviral oncogene, v-fms, was acquired by genetic recombination between a filine leukemia virus (FeLV) and proto-oncogene sequences (c-fms) of normal cat cells. The v-fms gene is found in only one strain of feline sarcoma virus (FeSV) and encodes a transforming glycoprotein of unknown function. The product of the c-fms gene has not been identified, nor has its relationship to the viral transforming protein been elucidated. This proposal describes the detailed characterization of the v-fms-coded glycoprotein, defines the first steps in identifying the product of the cellular proto-oncogene, and attempts to clarify the role of these proteins in malignant transformation. Using the recently determined nucleotide sequence of a biologically active clone of FeSV DNA, we propose to place site-directed mutations in the v-fms gene. In particular, mutations will be directed to (i) limited regions of the v-fms gene which show unexpected homology to v-onc genes of the tyrosine kinase gene family, and to (ii) signal sequences which are presumed to play a role in the subcellular localization of the transforming glycoprotein. The transforming activity of altered genes will be assayed by DNA transfection onto cultured cells. Cotransfection with dominant selectable markers will be used to isolate nontransforming variants whose encoded products will be biochemically compared to those of the wild type transforming gene. The induced biochemical alterations in the v-fms gene product will be correlated with the topology of the protein and its transforming activity. In parallel studies, genomic and cDNA clones of the c-fms gene will be used to predict the primary structure of its product, thereby facilitating its identification and characterization. Recombinant DNA molecules between c-fms and v-fms will be prepared in an effort to activate the latent transforming potential of the cellular proto-oncogene. It is anticipated that a detailed characterization of domains in the v-fms-coded glycoprotein important in post-translational processing, intracellular transport, and transformation will provide the basis for activating the cellular proto-oncogene and determining its function. The latter studies will emphasize the structure and expression of the human c-fms proto-oncogene and its potential role in cancer.