Polycystin activators as novel therapeutic approach for ADPKD

项目摘要 离子通道控制着受精、增殖、发育、学习和记忆等多种过程。 离子通道是多跨膜蛋白，每秒转运约106至107个离子穿过 膜。初级纤毛是从顶端质膜伸出的触角状突起， 富含一种叫做多囊蛋白的离子通道。多囊蛋白突变导致常染色体 显性多囊肾病（ADPKD），表现为肾脏和其他器官的囊肿形成， 例如肝脏和胰腺。多囊蛋白通道在空间上和 时间调节，从而有助于纤毛信号级联仍然知之甚少。的 该项目的中心目标是开发多囊蛋白通道的小分子激活剂作为新的工具， 在分子和细胞水平上研究多囊蛋白信号传导的基本机制。此类工具 目前研究界还无法获得，可能作为ADPKD的新疗法发挥作用。 近年来，离子通道激动剂作为一种新的治疗药物被开发出来，以恢复功能失调的离子通道 人类的活动。实例包括囊性纤维化跨膜传导调节因子的活化剂 本发明提供了用于治疗囊性纤维化的CFTR离子通道作为治疗剂的用途。该提案包含两个具体的 目的：第一个目的提出了基于成像的高通量筛选来鉴定多囊蛋白通道的激动剂。 使用我们最近开发的新的细胞测定来询问多囊蛋白离子通道活性。在 第二个目的是测试这些激动剂恢复具有错义的多囊蛋白通道活性的效力 PC1或PC2的突变。这种错义突变可能被特定的激动剂激活， 约35%的致病性ADPKD突变。

PROJECT SUMMARY Ion channels control such diverse processes as fertilization, proliferation, development, learning and memory. Ion channels are multispan transmembrane proteins that transport ~106 to 107 ions per second across membranes. The primary cilium is an antenna-shaped protrusion from the apical plasma membrane and are enriched in a specific subset of ion channels called polycystins. Mutations in polycystins cause Autosomal Dominant Polycystic Kidney Disease (ADPKD), which manifests in cyst formation in kidney and other organs, such as liver and pancreas. The molecular mechanisms by which polycystin channels are spatially and temporally regulated and thus contribute to ciliary signaling cascades still remains poorly understood. The central goal of this project is to develop small molecule activators of the polycystin channel as novel tools to study the fundamental mechanisms of polycystin signaling at the molecular and cellular level. Such tools are currently unavailable to the research community and are likely to function as novel therapeutics for ADPKD. Recently ion channel agonists have been developed as novel therapeutics to restore dysfunctional ion channel activity in humans. Examples include activators of cystic fibrosis transmembrane conductance regulator (CFTR) ion channels as therapeutics for the treatment of cystic fibrosis. This proposal contains two specific aims: the first aim proposes imaging-based high throughput screens to identify agonists of polycystin channels using novel cellular assays that we have recently developed to interrogate polycystin ion channel activity. In the second aim will test the potency of such agonists to restore activity of polycystin channels with missense mutations in PC1 or PC2. Such missense mutations can likely be revitalized by specific agonists and account for ~35% of all pathogenic ADPKD mutations.