Identification of new Wnt signaling components

新 Wnt 信号传导成分的鉴定

• 批准号: 6890016
• 负责人: KENNETH M CADIGAN
• 金额: $ 29.94万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-05-15 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6890016
• 关键词: DNA binding protein; Drosophilidae; arthropod genetics; biological signal transduction; cell differentiation; cell line; cell proliferation; complementary DNA; double stranded RNA; gene expression; gene mutation; gene targeting; genetic transcription; glycoproteins; messenger RNA; molecular cloning; protein protein interaction; protein signal sequence; protein structure function; tissue /cell culture

DESCRIPTION (provided by applicant): Cells receive and interpret signals from their extracellular environment through biochemical cascades known as signal transduction pathways. These pathways control many aspects of cell growth and differentiation. Mutations activating these processes are often found in human cancers. An important example of this is found in the Wnt signaling pathway. Wnts are secreted glycoproteins commonly used during invertebrate and vertebrate development that function through a highly conserved signaling apparatus. Recessive mutations in negative regulators of the pathway and gain-of-function mutations in positive effecters play a causal role in several cancers. Our goal is to identify new Wnt signaling components, by studying Wingless (Wg), a well characterized Drosophila Wnt. In one approach, a genetic screen was performed which identified a gene, gammy legs (gam), which blocks Wg signaling when over expressed. Removal of gam activity also leads to loss of Wg signaling. gam encodes a protein with a putative nuclear localization sequence and a PHD finger. The molecular mechanism of Gam action in Wg signaling will be persued using genetic epistasis in flies and fly cell culture, identification of possible binding partners for the Gam protein and a systematic structure/function mutational analysis. Two predicted human genes that have signficant sequence similarity to gam have also been identified in the database. These genes will be cloned and analyzed to determine if they play an important role in Wnt signaling in human cell lines. The second approach takes advantage of the recent finding that incubating Drosophila cells with dsRNA corresponding to a particular gene specify targets that gene's mRNA for degradation. This technology will be used to screen potential fly homologs of several factors recently implicated in vertebrate Wnt signaling through protein-protein interaction screens. If reduction of a gene's expression causes Wg signaling to be effected in cell culture, then fly mutants lacking these genes will be isolated and analyzed for Wg signaling defects. Obtaining genetic confirmation of the importance of these putative Wnt signaling components will provide the confidence to pursue their study in the context of cancer biology and as targets for drug discovery.

描述（由申请人提供）： 细胞从其细胞外环境接收和解释信号 通过称为信号转导途径的生化级联反应。这些 途径控制细胞生长和分化的许多方面。突变 激活这些过程通常在人类癌症中发现。一个重要的 示例在Wnt信号通路中找到。 Wnt是分泌的 在无脊椎动物和脊椎动物发育期间常用的糖蛋白 该功能通过高度保守的信号设备。隐性 途径的负调节因子的突变和功能收益突变 在积极效应中，在几种癌症中起因果作用。我们的目标是 通过研究无翼（WG）来识别新的Wnt信号传导组件， 果蝇Wnt的特征。 在一种方法中，进行了鉴定基因的遗传筛选， Gammy腿（GAM），它在表达过度时会阻止WG信号。去除 GAM活动还导致WG信号的损失。游戏编码一种蛋白质 推定的核定位序列和PhD手指。分子 GAM动作在WG信号中的机制将使用遗传来实现 苍蝇和蝇培养中的上毒，鉴定可能的结合 GAM蛋白的合作伙伴和系统的结构/功能突变 分析。两个具有引人注目序列相似性的预测的人类基因 GAM在数据库中也已确定。这些基因将被克隆 并分析以确定它们是否在Wnt信号中起重要作用 人类细胞系。 第二种方法利用了最近孵化的发现 与特定基因相对应的dsRNA的果蝇细胞指定靶标 该基因的mRNA降解。该技术将用于筛选 最近与脊椎动物有关的几个因素的潜在飞行同源物 Wnt信号通过蛋白质 - 蛋白质相互作用筛选。如果减少 基因的表达会导致WG信号在细胞培养中产生，然后飞行 缺乏这些基因的突变体将被隔离并分析WG信号传导 缺陷。获得对这些推定的重要性的遗传确认 Wnt信号传导组件将提供信心，以便在 癌症生物学的背景和作为药物发现的靶标。