Elucidating the Roles of the Membrane-Binding Proteins ciBAR1 and ciBAR2 in Ciliogenesis

项目摘要 气道运动纤毛在粘液纤毛清除中起重要作用，粘液纤毛清除是呼吸道的主要先天防御机制。 通过将吸入的病原体困在粘液中向上并排出呼吸道，纤毛受损 慢性肺部疾病患者中常见的功能，以及导致 异常纤毛形成和功能丧失通常导致遗传异质性的发展， 多系统紊乱叫做纤毛病目前的文献表明， 和包封纤毛的纤毛膜的形态参与维持纤毛功能， 体内平衡然而，分子球员和机制的形成和维持， 对睫状膜的了解仍然很少。本提案的总体目标是确定 膜结合蛋白ciBAR 1和2（以前称为FAM 92 A和B）的生理作用， 纤毛发生和气道纤毛细胞分化。两种ciBAR蛋白 具有单个Bin/Amphiphysin/Rvs（BAR）结构域，这允许它们二聚化并形成新月形- 形状的结构来优先感知和雕刻弯曲的膜。以前的研究已经表明 ciBAR 1和2与睫状蛋白Chibby 1（Cby 1）结合，Cby 1在纤毛前囊泡募集和基底膜形成中起作用。 纤毛细胞分化早期的体对接。cIBAR 1和2与Cby 1共定位于睫状体 在纤毛发生中起关键作用，但其体内功能目前尚不清楚。中央 这一提议的假设是，ciBAR 1和2在纤毛发生和分化中起关键作用， 气道纤毛细胞通过其膜结合和成形活性。为了解决这个问题，我将 使用我们实验室开发的新的ciBAR 1-/-和ciBAR 2-/-敲除小鼠模型，并提出 遵循具体目标。在目标1中，我将研究小鼠中ciBAR 1或ciBAR 2的缺失是否会导致纤毛损伤。 气管有缺陷在目标2中，我将研究ciBAR蛋白在形成和维持细胞内的作用。 利用原代细胞培养、生物化学方法和细胞生物学方法， 接近。总的来说，我提出的项目将阐明ciBAR 1和2在体内的功能， 纤毛发生和气道纤毛细胞分化，并推进我们对纤毛如何发生的现有知识 膜的产生和维持贯穿纤毛发生的整个过程。

PROJECT SUMMARY Airway motile cilia play an important role in mucociliary clearance, the primary innate defense mechanism of the lung, by propelling inhaled pathogens trapped in mucus up and out of the respiratory tract. Impaired ciliary function is commonly found in patients with chronic pulmonary diseases, and genetic mutations that result in aberrant cilia formation and loss of function often lead to the development of genetically heterogenous, multisystem disorders called ciliopathies. The current body of literature suggests that the unique composition and morphology of the ciliary membrane that envelopes the cilium are involved in maintaining cilia function and homeostasis. However, the molecular players and mechanisms underlying the formation and maintenance of the ciliary membrane remain poorly understood. The overarching objective of this proposal is to define the physiological roles of the membrane-binding proteins ciBAR1 and 2 (formerly known as FAM92A and B) in ciliogenesis and airway ciliated cell differentiation by using novel knockout mouse models. Both ciBAR proteins possess a single Bin/Amphiphysin/Rvs (BAR) domain, which allows them to dimerize and form crescent- shaped structures to preferentially sense and sculpt curved membranes. Previous studies have shown that ciBAR1 and 2 bind to the ciliary protein Chibby1 (Cby1), which acts in preciliary vesicle recruitment and basal body docking during early stages of ciliated cell differentiation. ciBAR 1 and 2 colocalize with Cby1 at the ciliary base and play crucial roles in ciliogenesis, but their in vivo functions are currently unknown. The central hypothesis of this proposal is that ciBAR1 and 2 play key roles in ciliogenesis and differentiation of airway ciliated cells via their membrane-binding and shaping activity. To address this hypothesis, I will use novel ciBAR1-/- and ciBAR2-/- knockout mouse models developed by our laboratory and propose the following Specific Aims. In Aim 1, I will investigate if the loss of ciBAR1 or ciBAR2 in mice results in ciliary defects in the trachea. In Aim 2, I will examine the roles of ciBAR proteins in formation and maintenance of ciliary membranes during ciliogenesis using primary cell cultures, biochemical methods, and cell biological approaches. Collectively, my proposed project will shed light on the in vivo functions of ciBAR1 and 2 in ciliogenesis and airway ciliated cell differentiation and advance our existing knowledge of how the ciliary membrane is generated and maintained throughout the process of ciliogenesis.