Wnt/Ca2+ Function in Development and Tumor Suppression

Wnt/Ca2 在发育和肿瘤抑制中的功能

• 批准号: 7229547
• 负责人: DIANE C SLUSARSKI
• 金额: $ 22.1万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7229547
• 关键词: Abdomen; Address; Adult; Affect; Binding; Binding Proteins; Biological; Calcium; Coupled; Development; Developmental Biology; Embryo; Event; Frequencies; Gene Expression; Genes; Genetic; Goals; Growth; Image; Image Analysis; Malignant Neoplasms; Mediating; Mediator of activation protein; Minor; Molecular Genetics; Neoplasms; Paper; Pathway interactions; Phenotype; Phosphoproteins; Ploidies; Protein Binding; Role; Signal Pathway; Signal Transduction; Signaling Protein; Testing; Tissues; Tumor Suppression; Tumor Suppressor Proteins; Whole Organism; Zebrafish; anticancer research; beta catenin; calmodulin-dependent protein kinase II; cell motility; fascinate; genetic analysis; genetic strain; in vivo; insight; loss of function; mutant; protein distribution; sensor; tumor

DESCRIPTION (provided by applicant): Beta-catenin activity has a profound impact in both development and cancer. Activation of the canonical Wnt path (Wnt/Beta-catenin) results in the accumulation of Beta-catenin. Non-canonical Wnts influence cell movement and modulate calcium release (Wnt/Ca2+). We have demonstrated that genetic depletion of Wnt-5 (pipetail, ppt), a non-canonical Wnt, results in reduced Ca2+ release and increased beta-catenin accumulation in zebrafish. How the different Wnt pathways interact is not well known. We hypothesize that non-canonical Wnts, through Ca2+ modulation, function as negative-regulators of Wnt/Beta-catenin signaling, raising the fascinating possibility that Wnt-5 is a potential tumor suppressor. Our goal is to use molecular-genetic analyses coupled with in vivo imaging to investigate the mechanisms of Wnt/Ca2+ activity in development and in tumor suppression. In Specific Aim 1, we determine if Beta-catenin stabilization in Wnt-5 mutant (ppt) embryos is a direct result of Wnt/Ca2+ function. We will determine whether the facilitated beta-catenin activity in ppt mutants can be suppressed by Wnt-5 misexpression, or by manipulating Ca2+ release. In Specific Aims 2 and 3, we explore several potential mechanisms by which Wnt/Ca2+ activity could be antagonizing Wnt/Beta-catenin activity. We will determine if Wnt-5-mediated phenotypes (gain- and loss-of-function) require the activity of Axin and/or GSK, both key players in canonical Wnt signaling. The antagonistic interactions could be mediated by competition for Dsh (Dishevelled), a protein that signals in both Wnt pathways. We will investigate the role of naked cuticle, a calcium sensor that binds Dsh, as a potential mediator of Dsh sequestration to a particular signaling pathway. And lastly, we have found that Wnt/Ca2+ mutants develop spontaneous tumors. In aim 4, we will characterize the affected tissues and investigate the biological role of Wnt/Ca2+ activity as a potential tumor suppressor. In this new initiative in the lab, we apply our developmental biology expertise with in vivo image analysis of the whole organism to generate new insights into the mechanisms of tumor formation and growth

描述（由申请人提供）：β-连环蛋白活性对发育和癌症都有深远的影响。经典 Wnt 路径（Wnt/Beta-catenin）的激活会导致 Beta-catenin 的积累。非典型 Wnt 影响细胞运动并调节钙释放 (Wnt/Ca2+)。我们已经证明，Wnt-5（pipetail，ppt）（一种非典型 Wnt）的基因缺失会导致斑马鱼 Ca2+ 释放减少和 β-连环蛋白积累增加。不同的 Wnt 通路如何相互作用尚不清楚。我们假设非经典 Wnt 通过 Ca2+ 调节，充当 Wnt/β-连环蛋白信号传导的负调节因子，从而提出了 Wnt-5 是潜在肿瘤抑制因子的令人着迷的可能性。 我们的目标是利用分子遗传学分析与体内成像相结合来研究 Wnt/Ca2+ 活性在发育和肿瘤抑制中的机制。在具体目标 1 中，我们确定 Wnt-5 突变体 (ppt) 胚胎中的 β-连环蛋白稳定是否是 Wnt/Ca2+ 功能的直接结果。我们将确定 ppt 突变体中促进的 β-连环蛋白活性是否可以通过 Wnt-5 错误表达或通过操纵 Ca2+ 释放来抑制。在具体目标 2 和 3 中，我们探索了 Wnt/Ca2+ 活性拮抗 Wnt/β-catenin 活性的几种潜在机制。我们将确定 Wnt-5 介导的表型（功能获得和丧失）是否需要 Axin 和/或 GSK 的活性，两者都是典型 Wnt 信号传导的关键参与者。拮抗相互作用可以通过 Dsh (Dishevelled) 的竞争来介导，Dsh 是一种在两条 Wnt 通路中发出信号的蛋白质。我们将研究裸角质层（一种结合 Dsh 的钙传感器）作为 Dsh 隔离到特定信号通路的潜在介质的作用。最后，我们发现 Wnt/Ca2+ 突变体会​​产生自发性肿瘤。在目标 4 中，我们将表征受影响的组织并研究 Wnt/Ca2+ 活性作为潜在肿瘤抑制因子的生物学作用。在实验室的这项新举措中，我们运用发育生物学专业知识对整个生物体进行体内图像分析，以产生对肿瘤形成和生长机制的新见解