MECHANISM OF TRANSFORMATION BY THE V-MYB ONCOGENES

V-myb癌基因可引起鸡急性单核细胞白血病 诱导正常骨髓单核细胞发生白血病转化 文化。在上一个资助期内，我们证明了 V-Myb蛋白激活模型报告基因转录的能力 基因与其引起白血病转化的能力有很好的相关性。我们 也建立了一系列转录激活和 V-Myb的序列特异性DNA结合，并用它们定位了几个 V-Myb蛋白中的功能结构域通过生化组合 和基因分析。 C-myb是产生v-myb的正常细胞基因，对 脊椎动物的造血功能。与myb相关的基因也已被发现。 在昆虫、植物、细胞黏菌和酵母菌中。最近，它已经 已发现分裂酵母的细胞分裂周期基因cdc5 裂殖酵母编码的一种蛋白质与 C-Myb.这些结果表明，对转型有更好的理解 通过v-Myb可能对理解基本细胞有更广泛的意义 所有真核生物共有的循环机械。 我们对未来五年的研究有三个主要目标 项目。首先，我们想要更详细地了解分子 V-Myb蛋白的哪些特征对白血病是必要的 转型。第二，我们想要确定和描述 V-Myb与之相互作用的其他细胞成分。第三，我们有 建立了一个模型，说明在庞氏链霉菌中，cdc5蛋白的功能如何 与v-Myb的组织特异性转化有关，并希望测试 这是试验性的。因此，我们的具体目标是下一步的资金 时间段如下： 1)为了确定哪些v-Myb残基是DNA结合所必需的， 转录激活和白血病转化。 2.)鉴定相互作用的宿主细胞蛋白质和DNA序列 直接使用v-Myb。 3.)检测v-Myb对白血病细胞周期的调节作用 细胞和分裂酵母中。

The v-myb oncogene causes acute monoblastic leukemia in chickens and induces the leukemic transformation of normal myelomonocytic cells in culture. During the previous funding period, we demonstrated that the ability of the v-Myb protein to activate transcription of a model reporter gene correlated well with its ability to cause leukemic transformation. We also established a number of assays for transcriptional activation and sequence-specific DNA binding by v-Myb and used them to map several functional domains within the v-Myb protein by a combination of biochemical and genetic analyses. c- myb, the normal cellular gene from which v-myb arose, is essential for vertebrate hematopoiesis. Genes related to myb have also been identified in insects, plants, cellular slime molds, and yeasts. Recently, it has been shown that cdc5, a cell division cycle gene of the fission yeast Schizosaccharomyces pombe, encodes a protein with significant similarity to c-Myb. These results suggest that a better understanding of transformation by v-Myb may have broader implications in understanding the basic cell cycle machinery common to all eukaryotes. We have three major goals for the next five years of research on this project. First, we would like to understand in greater molecular detail which features of the v-Myb protein are essential for leukemic transformation. Second, we would like to identify and characterize the other cellular components with which v-Myb interacts. Third, we have developed a model of how the function of the Cdc5 protein in S. pombe relates to tissue-specific transformation by v-Myb and would like to test it experimentally. Therefore, our specific aims for the next funding period are as follows; 1.) To determine which residues of v-Myb are essential for DNA-binding, transcriptional activation, and leukemic transformation. 2.) To identify host cell proteins and DNA sequences which interact directly with v-Myb. 3.) To test the ability of v-Myb to regulate the cell cycle in leukemic cells and in fission yeast.