Regulators of Dishevelled Function in the Wnt Signaling Pathway

Wnt 信号通路中紊乱功能的调节因子

• 批准号: 8525415
• 负责人: ATHULA H WIKRAMANAYAKE
• 金额: $ 7.12万
• 依托单位: UNIVERSITY OF MIAMI CORAL GABLES
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-08 至 2014-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8525415
• 关键词: Animals; Binding; Biochemical; Caenorhabditis elegans; Cells; Co-Immunoprecipitations; Code; Complex; Degenerative Disorder; Development; Disease; Disease Progression; Drosophila genus; Dsh protein; Egg Proteins; Embryo; Embryonic Development; Goals; Homeostasis; Homologous Gene; Human; Inherited; Intervention; Invertebrates; Knowledge; Laboratories; Lead; Ligands; Malignant Neoplasms; Mass Spectrum Analysis; Mediating; Messenger RNA; Mission; Molecular; Outcome; Ovum; Pathway interactions; Procedures; Process; Proteins; Public Health; Publishing; Reagent; Regulation; Research; Role; Sea Urchins; Signal Pathway; Signal Transduction; Staging; Structure; Study models; Syndrome; System; Testing; Therapeutic Intervention; Tissues; Translations; Work; base; egg; embryo stage 2; embryo tissue; human disease; in vivo; insight; novel; novel strategies; polypeptide; receptor; scaffold

DESCRIPTION (provided by applicant): The Wnt signaling pathway regulates an astounding array of processes during development and homeostasis in animals, and its misregulation leads to numerous syndromes and degenerative diseases in humans. How Wnt ligands can activate context-specific signals downstream of the Wnt receptor complex is not well understood. The long-term goal of this work is to understand the molecular mechanisms that mediate context- dependent Wnt signaling during development. The Dishevelled (Dvl) protein is a central hub of Wnt signal transduction that integrates and transduces upstream signals through distinct cytoplasmic cascades. The regulation of this enigmatic protein in the Wnt pathway remains one of the enduring unsolved problems in this field. Recent work has emphasized the critical importance of cytoplasmic Dvl puncta for Wnt signaling via the Wnt/?-catenin signaling pathway, but how these puncta influence ?-catenin nuclearization is poorly understood. In sea urchins, Dvl puncta accumulate in a specialized domain in the egg cortex at the vegetal pole, and these structures correlate with highly restricted activation of Wnt/??-catenin signaling in vegetal blastomeres. In addition, functional studies have shown that Dvl is only able to activate Wnt/??-catenin signaling in vegetal pole blastomeres. These observations suggest that molecules that co-localize with Dvl in puncta at the vegetal cortex may regulate Dvl activity during Wnt/??-catenin signaling. A procedure has been developed in the applicant's laboratory to isolate biochemical quantities of sea urchin egg cortices with attached endogenous Dvl puncta. Hence, the overall objective of this application is to identify Dvl partner proteins in puncta from isolated egg cortices that mediate localized activation of Dvl during embryogenesis. The central hypothesis is that Dvl puncta are scaffolds for localized activation of Wnt/??-catenin signaling in early embryos, and that Dvl-associated proteins in puncta regulate Dvl function in this pathway. The rationale that underlies this research is that Dvl-associated proteins in puncta are attractive candidate molecules for context-specific regulation of Dvl activity. Using excellent immuno-reagents to Dvl produced in the laboratory, several putative Dvl associated proteins from egg and cortex lysates have been identified using Dvl Co-Immunoprecipitation followed by mass spectrometry. In this application, two of these proteins will be functionally analyzed to determine their roles in regulating Dvl localization, stability, and activation during early embryogenesis. Te contribution of the proposed study is identification of critical Dvl partner proteins that may regulate its activity in Wnt signaling. The significance of this contribution is that it will provie novel insight into mechanisms of context-dependent Dvl regulation and Wnt signaling during embryonic development and tissue homeostasis. As Wnt signaling is highly conserved and broadly deployed, our results may be extrapolated to better understand aspects of development in other species as well as the molecular basis for many human diseases. These advances will identify novel targets for pharmacological interventions of these diseases.

描述（由申请人提供）：Wnt 信号通路在动物的发育和稳态过程中调节一系列令人震惊的过程，其失调会导致人类出现多种综合征和退行性疾病。 Wnt 配体如何激活 Wnt 受体复合物下游的上下文特异性信号尚不清楚。这项工作的长期目标是了解发育过程中介导背景依赖性 Wnt 信号传导的分子机制。 Disheveled (Dvl) 蛋白是 Wnt 信号转导的中心枢纽，通过不同的细胞质级联整合和转导上游信号。 Wnt 通路中这种神秘蛋白质的调控仍然是该领域长期未解决的问题之一。最近的工作强调了细胞质 Dvl 点对于通过 Wnt/β-连环蛋白信号通路的 Wnt 信号传导至关重要，但这些点如何影响 β-连环蛋白核化却知之甚少。在海胆中，Dvl puncta 积聚在植物极卵皮层的一个特殊结构域中，这些结构与植物卵裂球中 Wnt/β-catenin 信号传导的高度受限激活相关。此外，功能研究表明，Dvl 只能激活植物极卵裂球中的 Wnt/β-catenin 信号传导。这些观察结果表明，与植物皮层斑点中的 Dvl 共定位的分子可能在 Wnt/β-连环蛋白信号传导过程中调节 Dvl 活性。申请人的实验室已开发出一种程序来分离具有附着的内源性Dvl斑点的海胆卵皮层的生化量。因此，本申请的总体目标是从 Puncta 中鉴定 Dvl 伴侣蛋白 分离的卵皮质在胚胎发生过程中介导 Dvl 的局部激活。中心假设是 Dvl puncta 是 Wnt/β-catenin 信号传导局部激活的支架。 早期胚胎中，斑点中的 Dvl 相关蛋白调节该途径中的 Dvl 功能。这项研究的基本原理是，斑点中的 Dvl 相关蛋白很有吸引力 Dvl 活性的上下文特异性调节的候选分子。使用实验室生产的针对 Dvl 的优质免疫试剂，通过 Dvl 免疫共沉淀和质谱分析，鉴定了来自鸡蛋和皮质裂解物的几种假定的 Dvl 相关蛋白。在此应用中，将对其中两种蛋白质进行功能分析以确定 它们在早期胚胎发生过程中调节 Dvl 定位、稳定性和激活中的作用。拟议研究的贡献是鉴定了关键的 Dvl 伴侣蛋白，这些蛋白可能调节其在 Wnt 信号传导中的活性。这一贡献的意义在于，它将为胚胎发育和组织稳态过程中背景依赖性 Dvl 调节和 Wnt 信号传导机制提供新的见解。由于 Wnt 信号传导高度保守且广泛部署，我们的结果可以推断以更好地了解其他物种的发育方面以及许多人类疾病的分子基础。这些进展将为这些疾病的药物干预确定新的靶标。

项目成果

Strong and selective adsorption of lysozyme on graphene oxide.

溶菌酶在氧化石墨烯上的强选择性吸附。

• 发表时间: 2014-04-23
• 影响因子: 9.5
• 作者: Li, Shanghao;Mulloor, Jerome J;Wang, Lingyu;Ji, Yiwen;Mulloor, Catherine J;Micic, Miodrag;Orbulescu, Jhony;Leblanc, Roger M
• 通讯作者: Leblanc, Roger M