Chibby and Wnt Signaling in Ciliated Cell Differentiation

纤毛细胞分化中的 Chibby 和 Wnt 信号转导

• 批准号: 8442395
• 负责人: KEN-ICHI TAKEMARU
• 金额: $ 42.8万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2016-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8442395
• 关键词: Address; Affinity Chromatography; Apical; Back; Binding; Biological Phenomena; Biological Process; Breathing; Cell Differentiation process; Cell Line; Cells; Chronic; Cilia; Clinical; Defect; Defense Mechanisms; Development; Disease; Epithelial Cells; Epithelium; Functional disorder; Genes; Goals; Hair; Human; Infection; Knockout Mice; Knowledge; Link; Lung; Mass Spectrum Analysis; Mediating; Molecular; Mucociliary Clearance; Mucous body substance; Mus; Nose; Outcome; Patients; Pharyngeal structure; Phenotype; Physiological; Play; Prevention; Prevention strategy; Primary Ciliary Dyskinesias; Proteins; Recurrence; Research; Resources; Respiratory Insufficiency; Respiratory System; Respiratory Tract Infections; Respiratory tract structure; Role; Signal Pathway; Signal Transduction; Structure of respiratory epithelium; Surface; Therapeutic; Transcriptional Activation; Transcriptional Regulation; Wnt proteins; Work; base; cilium biogenesis; clinically significant; experience; human disease; in vivo; microorganism; novel therapeutics; particle; pathogen; programs; protein complex; public health relevance; research study; transcription factor

DESCRIPTION (provided by applicant): Motile cilia are abundant in our respiratory tract, and beat synchronously in waves to propel inhaled debris and pathogens entrapped in mucus to the pharynx. This provides an important innate defense mechanism against respiratory infections. Motile cilia are usually found as clusters of 100 to 300 on the apical surface of a ciliated cell in the respiratory epithelium. Dysfunction of motile cilia has been linked to human diseases, especially primary ciliary dyskinesia (PCD). Despite their clinical importance, little is known about the key molecules and signaling pathways that govern motile ciliogenesis and ciliated cell differentiation. Therefore, understanding these fundamental biological phenomena is crucial for developing novel therapeutic strategies for the prevention and treatment of PCD and other cilia-related disorders. Chibby (Cby) was originally isolated as an evolutionarily conserved antagonist of the Wnt/¿-catenin signaling pathway. Cby physically interacts with the pivotal downstream coactivator ¿-catenin and inhibits ¿-catenin-mediated transcriptional activation. Intriguingly, Cby-knockout (Cby-/-) mice suffer from recurrent respiratory infections due to a complete absence of mucociliary transport activity, reminiscent of PCD. Our studies further revealed that ciliated cells in the nasal and lung epithelia of Cby-/- mice are poorly differentiated characterized by a markedly decreased number of motile cilia. Consistent with this phenotype, we found that endogenous Cby protein localizes to the base of cilia. Our findings therefore establish that Cby plays an essential role in proper formation/function of motile cilia in the respiratory tract. However, the cellular and molecular bases underlying the ciliary defects of Cby-/- mice remain largely unexplored. In addition, whether the ciliogenic function of Cby relates to Wnt/¿-catenin signaling is unclear. The goal of this proposal is to elucidate the roles of Cby, Cby-interacting proteins and Wnt/ ¿-catenin signaling in motile ciliogenesis and tracheal ciliated cell differentiation. In order to achieve this goal, we propose the following Specific Aims: Specific Aim 1. Investigate the role of Cby in tracheal ciliated cell differentiation; Specific Aim 2. Examine transcriptional regulation of the Cby gene during differentiation of tracheal ciliated cells; Specific Aim 3. Isolate Cby-binding partners and define their roles in ciliated cell differentiation. We expect that these experiments will contribute to a fundamental understanding of the molecular and cellular mechanisms of ciliogenesis and ciliated cell differentiation.

描述（由申请人提供）：我们的呼吸道中含有丰富的活动纤毛，它们以波浪形式同步跳动，将吸入的碎片和粘液中的病原体推入咽部。这提供了针对呼吸道感染的重要先天防御机制。通常在呼吸道上皮纤毛细胞的顶端表面上发现 100 至 300 个活动纤毛簇。运动纤毛的功能障碍与人类疾病有关，尤其是原发性纤毛运动障碍（PCD）。尽管它们具有临床重要性，但人们对控制运动纤毛发生和纤毛细胞分化的关键分子和信号通路知之甚少。因此，了解这些基本的生物学现象对于开发预防和治疗 PCD 和其他纤毛相关疾病的新治疗策略至关重要。 Chibby (Cby) 最初是作为 Wnt/¿-catenin 信号通路的进化保守拮抗剂被分离出来的。 Cby 与关键下游共激活因子 β-catenin 发生物理相互作用，并抑制 β-catenin 介导的转录激活。有趣的是，Cby 基因敲除 (Cby-/-) 小鼠由于完全缺乏粘液纤毛转运活性而遭受反复呼吸道感染，这让人想起 PCD。我们的研究进一步表明，Cby-/-小鼠鼻和肺上皮细胞中的纤毛细胞分化不良，其特征是运动纤毛数量显着减少。与这种表型一致，我们发现内源性 Cby 蛋白定位于纤毛基部。因此，我们的研究结果表明，Cby 在呼吸道运动纤毛的正常形成/功能中发挥着重要作用。然而，Cby-/- 小鼠纤毛缺陷背后的细胞和分子基础在很大程度上仍未被探索。此外，Cby 的纤毛形成功能是否与 Wnt/¿-连环蛋白信号传导有关尚不清楚。该提案的目标是阐明 Cby、Cby 相互作用蛋白和 Wnt/β-连环蛋白信号在运动纤毛发生和气管纤毛细胞分化中的作用。为了实现这一目标，我们提出以下具体目标： 具体目标1.研究Cby在气管纤毛细胞分化中的作用；具体目标2.检查气管纤毛细胞分化过程中Cby基因的转录调控；具体目标 3. 分离 Cby 结合伴侣并确定它们在纤毛细胞分化中的作用。我们期望这些实验将有助于对纤毛发生和纤毛细胞分化的分子和细胞机制的基本理解。