REGULATION OF CELL GROWTH BY THE WILMS TUMOR GENE

描述：（改编自研究者摘要）肾母细胞瘤 抑制基因wt1编码锌指转录因子WT1。 一 wt1基因突变的数量已被确定在Wilms的子集 肿瘤、间皮瘤、卵巢肿瘤和急性髓性白血病，提示 WT1的功能障碍在许多肿瘤中可能是重要的。 然而，在这方面， 实际上对WT1调节的内源基因一无所知， 因此WT1触发的信号通路以及突变的WT1 影响这些通路导致肾母细胞瘤仍有待发现。 研究者研究的长期目标是描述 WT1在发育过程中的正常功能和 突变的WT1导致了肾母细胞瘤的发生。 调查人员 最近克隆了一个基因，它在细胞中的表达量是 表达WT1的细胞中的WT1水平高于检测不到WT1水平的细胞。 该基因 视网膜母细胞瘤（Rb）抑制相关蛋白（AP） （RbAp46），一种与Rb物理相互作用的核蛋白。的 研究人员最近克隆并表达了 RbAp46，并分析其对肿瘤细胞的作用。 值得注意的是， 外源RbAp46抑制四种肿瘤细胞系中的四种的生长， 提示RbAp46本身具有生长抑制活性。 的 研究人员现在计划建立 WT1和RbAp46在不同肿瘤细胞和小鼠中的表达水平 采用北方和原位方法， 杂交分析 他们计划分析RbAp46的启动子区域， 以确定WT1是否直接调节RbAp46的表达。 他们 计划探索RbAp46作为WT1功能介导剂的可能作用 通过表达外源性RbAp46或通过下调细胞中的RbAp46。 的 研究人员计划探索RbAp46发挥作用的机制， 生长抑制剂，分析其对细胞周期的影响， 在ras信号通路上。 调查人员计划进行结构 和功能分析，以确定其所需的RbAp46的结构域 功能 研究人员计划鉴定出这些蛋白质， 与RbAp46通过免疫共沉淀和体内GST捕获测定， 如果需要，通过酵母双杂交策略。 希望这些 研究将为Wilms'的治疗干预奠定基础。 肿瘤和其他肿瘤。

DESCRIPTION: (Adapted from investigator's abstract) The Wilms' tumor suppressor gene, wt1, encodes a zinc finger transcription factor, WT1. A number of mutations to the wt1 gene have been identified in subsets of Wilms tumor, mesothelioma, ovarian tumor and acute myeloid leukemia, suggesting that dysfunction of WT1 may be important in many tumors. However, effectively nothing is known about the endogenous genes regulated by WT1, and thus the signaling pathways triggered by WT1 and how mutated WT1 influences these pathways to result in Wilms' tumor remain to be discovered. The long-term objective of the investigator's research is to characterize the normal functions of WT1 during development and the dysfunctions of mutated WT1 that lead to the genesis of Wilms' tumor. The investigators recently cloned a gene whose expression is over tenfold greater in cells expressing WT1 than in cells with undetectable levels of WT1. The gene was identified as retinoblastoma (Rb) suppressor associated protein (AP) (RbAp46), a nuclear protein that physically interacts with Rb. The investigators have recently cloned and expressed the full-length cDNA of RbAp46, and analyzed its effect on tumor cells. Remarkably, expression of exogenous RbAp46 suppressed growth in four out of four tumor cell lines, suggesting that RbAp46 itself has growth inhibitory activity. The investigators now plan to establish the positive correlation between the levels of WT1 and RbAp46 expression in different tumor cells and in mouse tissues from different stages of development using Northern and in situ hybridization analysis. They plan to analyze the promoter region of RbAp46 to determine whether WT1 directly regulates the expression of RbAp46. They plan to explore the possible roles of RbAp46 as a mediator of WT1 function by expressing exogenous RbAp46 or by down-regulating RbAp46 in cells. The investigators plan to probe the mechanisms by which RbAp46 functions as a growth inhibitor by analyzing its impact on the cell cycle and its influence on the ras signaling pathway. The investigators plan to perform structure and function analysis to identify the domain(s) of RbAp46 required for its function. The investigators plan to identify the proteins which interact with RbAp46 by co-immunoprecipitation and an in vivo GST capture assay and, if necessary, by a yeast two-hybrid strategy. It is hoped that these studies will lay the foundation of therapeutic intervention for the Wilms' tumor and other tumors as well.