Functoinal compartmentalization of hedgehog signal transduction in primary cilia

Hedgehog信号转导的功能区划 初生纤毛 摘要 初级纤毛是小的，触角状的细胞器，对脊椎动物的发育和 生理学。纤毛缺陷会导致人类疾病，称为纤毛病，其特征是广泛的 表型谱，突出了它们在多种细胞类型和器官中的重要作用。 纤毛虽然没有完全被膜包围，但形成了一个独特的隔室， 接收和发送细胞外信号。它们的功能关键取决于动态 蛋白质组成和定位的变化。刺猬(HH)信号转导， 对胚胎发育、成人组织再生和癌症至关重要，主要发生在 在初级纤毛上。HH转导蛋白Smoothed(Smo)、Patched1(Ptch1)、 融合抑制因子(SuFU)和Gli2在细胞接受HH时穿梭于纤毛内外 信号和定位的改变与通路的激活相关。基因的分子基础 这些步骤中的大多数都不清楚。在这份提案中，我们将在HH之前的工作基础上再接再厉 在纤毛和中心体的细胞生物学中，对信号转导的回答尚未解决 纤毛和HH信号转导中的蛋白质区划问题。我们会申请 高分辨率光学显微镜、分子遗传学和新的生化方法 确定与纤毛蛋白复合体的特定相互作用如何控制HH-转导 纤毛的动力学，以及更广泛地说，纤毛反应性是如何建立的；调查如何 纤毛内的ptch1相互作用调节Smo的激活；最后，我们将阐明如何 从纤毛中去除HH转导受到控制，扩展了我们最近发现的类RILP 蛋白质作为这一过程的调节器。 综上所述，我们建议建立高分辨率、空间和时间分辨率的 刺猬初级纤毛发出信号的图片。我们相信只有有这样一个人- 深入分析将有可能理解Hedgehog信号的分子基础。 好了！

Functional Compartmentalization of Hedgehog Signal Transduction in Primary Cilia Abstract Primary cilia are small, antenna-like organelles critical for vertebrate development and physiology. Defects in cilia result in human diseases called ciliopathies, characterized by a wide spectrum of phenotypes, highlighting their important role in multiple cell types and organs. Although not completely surrounded by a membrane, cilia form a distinct compartment that receives and transmits extracellular signals. Their function critically depends on the dynamic changes in protein composition and localization. The Hedgehog (Hh) signaling transduction, essential for embryonic development, adult tissue regeneration and cancer, largely takes place at primary cilia. The Hh-transduction proteins Smoothened (Smo), Patched1 (Ptch1), Suppressor of Fused (SuFu) and Gli2 shuttle into and out of cilia when cells receive the Hh signal, and changes in localization correlate with pathway activation. The molecular basis for most of these steps is not clear. In this proposal, we will build upon our previous work in Hh signal transduction and in the cell biology of cilia and centrosomes, to answer unresolved questions about protein compartmentalization in cilia and Hh signal transduction. We will apply high-resolution optical microscopy, molecular genetics and novel biochemical methods to determine how specific interactions with ciliary protein complexes control Hh-transducer dynamics in cilia, and, more broadly, how ciliary responsiveness is established; investigate how Ptch1 interactions within the cilium regulate Smo activation; finally, we will elucidate how removal of Hh-transducers from cilia is controlled, extending our recent discovery of Rilp-like proteins as regulators of this process. In summary, we propose to establish a high-resolution, spatially and temporally resolved picture of Hedgehog signaling in the primary cilium. We believe that only by having such an in- depth analysis will it be possible to understand the molecular basis of Hedgehog signaling. !