NOVEL ONCOGENES IN VIRUS INDUCED MYELOID TUMORS

BXH-2小鼠发生髓系白血病的高发原因是 与一种生态型小鼠白血病病毒的表达有关 (MULV)。MuLV作为插入突变剂在 导致白血病的细胞原癌基因的表达。自.以来 髓系白血病在小鼠中很罕见，100%的BXH-2小鼠会患上这种病 对于白血病，BXH-2小鼠代表了一种独特而强大的模型系统 髓系白血病发生相关基因的鉴定。我们有 证明了对病毒整合部位的分析发现 与人类疾病和小鼠疾病有关的新基因座(Evi2)。然而，我们 已经表明，集成到Evi2中的比例仅为10% 肿瘤分析表明，还有其他几个基因座是 病毒整合和参与髓系肿瘤发生的靶点。 我们最近发现了一个整合的NW公共部位，Meis1(髓样 亲生性病毒整合位点1)，在BXH-2髓系肿瘤中。我们有 发现15%的肿瘤在Meis1内有病毒整合，并且 Meis1的染色体位置表明它代表了一个新的基因座。一个 基因被鉴定为位于病毒整合和测序的两侧 分析表明该基因是一个与PBX相关的新的同源框基因 同源结构域家族(与前B细胞淋巴瘤有关的一个成员)。 我们在这项提案中的目标是描述MEIS1在 发育和白血病。此外，我们计划确定其他 BXH-2肿瘤中常见的病毒整合部位以及开始 确定宿主BXH-2小鼠在发展髓系白血病中的作用。 这些结果将不仅提供关于基因类型的信息 不仅与白血病有关，还与正常基因有关 造血术。 这个项目的具体目标是完成克隆和 Meis1基因座及其编码基因的特征。至 Meis-1蛋白在细菌表达载体中的表达及表达 抗Meis1蛋白的多克隆抗血清。抗血清将会是 用于确认MEIS-1的核定位以及研究 发育性表达。细菌产生的融合蛋白将是 用来开始鉴定Meis1的结合部位。Meis1基因在人类免疫系统中的作用 髓系细胞发育和白血病将由 正义和反义转录子在髓系细胞系和 小鼠骨髓。这三个目标的结果将加强我们的 一种新的同源异型盒的功能和表达的理解 吉恩。此外，我们计划分离出更多常见的病毒部位 一体化，目的是确定以下方面的补充小组 整合站点。最后，我们将探索 BXH-2小鼠的髓系细胞室以确定宿主的作用 在赋予疾病特异性的过程中。在这方面所取得的结果 该项目将建立在现有的小鼠相关基因数据库的基础上 髓系白血病的发生及其在人类中的潜在作用 肿瘤。最后，这些研究将提供有关TOT角色的信息 宿主在赋予疾病特异性方面发挥了作用。

BXH-2 mice develop a high incidence of myeloid leukemia that is causally associated with the expression of an ecotropic murine leukemia virus (MuLV). The MuLVs are acting as insertional mutagens to alter at the expression of cellular protooncogenes that contribute to leukemia. Since myeloid leukemia is rare in mice and 100% of BXH-2 mice develop this leukemia, BXH-2 mice represent a unique and powerful model system for the identification of genes involved in myeloid leukemogenesis. We have demonstrated that the analysis of the viral integration sites identifies new loci (Evi2) involved in human as well as murine disease. However, we have shown that integrations into Evi2 are present in only 10% of the tumors analyzed, indicating that there exists several other loci that are targets from viral integration and participation in myeloid tumorigenesis. We have recently identified a nw common site of integration, Meis1 (Myeloid ecotropic viral integration site 1), in the BXH-2 myeloid tumors. We have found that 15% of the tumors have viral integrations within Meis1 and that the chromosomal location of Meis1 suggests it represents a novel locus. A gene was identified that is flanked by the viral integrations and sequence analysis reveals the gene to be a novel homeobox gene related to the PBX homeodomain family (one member which is involved in pre-B cell lymphomas). Our goals in this proposal are to characterize the role of Meis1 in development and leukemia. In addition, we plan to identify additional common sites of viral integration in the BXH-2 tumors as well as begin to identify the role of the host BXH-2 mice in developing myeloid leukemia. These results will provide information not only as to types of genes that contribute to leukemia, but also to the genes that are involved in normal hematopoiesis. The specific goals of this project are to complete the cloning and characterization of the Meis1 genomic locus and its encoded gene. To express the Meis 1 protein in a bacterial expression vector and generate polyclonal antisera against at the Meis1 protein. The antisera will be used to confirm the nuclear localization of Meis 1 as well as study the developmental expression. The bacterially generated fusion protein will be used to begin to identify the binding site of Meis1. The role of Meis1 in myeloid cell development and leukemia will be explored by the overexpression of sense and antisense transcripts in myeloid cell lines and murine bone marrow. The results of these three aims will enhance our understanding of the function and expression of a novel homeobox containing gene. In addition, we plan to isolate additional common site of viral integration, with the aim of identifying complementation groups of integration sites. Finally, we are going to explore the mechanics of the myeloid cell compartment in BXH-2 mice to determine what role the host has in conferring the disease specificity. The results obtained in this project will build on the existing database of genes involved in murine myeloid leukemogenesis and the potential role of these genes in human neoplasia. Finally, these studies will provide information as tot the role the host plays in conferring disease specificity.