Elucidating the regulators of ciliogenesis

初级纤毛是从大多数静止的哺乳动物细胞表面发出的触角状突起 细胞纤毛对于感知细胞外信号和生长因子是必不可少的。它们由中心体组成 并以细胞周期依赖性方式被再吸收。在这些机制方面仍存在许多问题， 引起纤毛的组装和拆卸。例如，细胞骨架蛋白的重组， 微管蛋白修饰和核锚定已经出现，但机械连接到纤毛组装 和拆卸都没有很好地理解。我们已经开始鉴定纤毛发生所需的关键蛋白质， 包括Talpid 3，一种已知在信号传导中起作用的蛋白质。使用全蛋白质组方法鉴定Talpid 3- 我们分离了两个以前未表征的蛋白质LRRC 49和C11 orf 49，它们在蛋白质相互作用中起作用。 在抑制不适当的纤毛组装和维持微管蛋白谷氨酰化和 核形态学 在将细胞生物学和生物化学方法与基因编辑和使用体内基因编辑技术相结合的联合收割机的两个目的中， 模型，我们将（1）研究LRRC 49和C11 orf 49在纤毛及时组装和拆卸中的作用，（2） 研究LRRC 49和C11 orf 49如何调节核形态以及细胞骨架组装和动力学， 以及（3）测试微管蛋白谷氨酰化酶的广泛生物学作用及其与纤毛发生、微管形成和微管形成的关系。 稳定性和核膜组装。通过研究调节纤毛的关键蛋白的功能， 组装和拆卸，以及控制细胞骨架组织和核形状在体外和体内， 体内，我们将解决有关哺乳动物细胞生长和细胞周期进程的基本问题。

Primary cilia are antenna-like projections that emanate from the cell surface of most quiescent mammalian cells. Cilia are essential for sensing extracellular cues and growth factors. They assemble from centrosomes and are resorbed in a cell cycle-dependent manner. Many questions remain regarding the mechanisms that provoke cilium assembly and disassembly. For example, links between reorganization of cytoskeletal proteins, tubulin modifications, and nuclear anchoring have emerged, but mechanistic connections to cilium assembly and disassembly are not well understood. We have begun characterizing key proteins required for ciliogenesis, including Talpid3, a protein known to play a role in signaling. Using proteome-wide methods to identify Talpid3- interaction partners, we isolated two previously uncharacterized proteins, LRRC49 and C11orf49, that play a potent role in suppressing inappropriate cilium assembly and maintaining both tubulin glutamylation and nuclear morphology. In two Aims that combine cell biological and biochemical approaches with gene-editing and use of an in vivo model, we will (1) investigate a role for LRRC49 and C11orf49 in timely cilium assembly and disassembly, (2) examine how LRRC49 and C11orf49 regulate nuclear morphology and cytoskeleton assembly and dynamics, and (3) test the broad biological roles of tubulin glutamylases and their connections to ciliogenesis, microtubule stability, and nuclear envelope assembly. By investigating the function of key proteins that regulate cilium assembly and disassembly, as well as control of cytoskeleton organization and nuclear shape in vitro and in vivo, we will address fundamental questions related to mammalian cell growth and cell cycle progression.