Role of primary cilium-generated signaling in polycystic kidney disease

原代纤毛产生的信号在多囊肾病中的作用

基本信息

批准号：
10365417
负责人：
Saikat Mukhopadhyay
金额：
$ 62.67万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-01-15 至 2025-11-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10365417
关键词：
Address Adenylate Cyclase Adolescent Adult Affect Age Ankyrin Repeat Automobile Driving Autosomal Dominant Polycystic Kidney Biological Biosensor Cell Culture Techniques Cells Cilia Collaborations Complex Coupling Cultured Cells Cyclic AMP Cyclic AMP-Dependent Protein Kinases Cyst Data Defect Development Dilatation - action Disease Disease Progression Disease model Embryo Epithelial Exhibits GTP-Binding Proteins Genes Genetic Epistasis Growth Guanosine Triphosphate Phosphohydrolases Human Kidney Knock-out Liquid substance Membrane Membrane Proteins Modeling Molecular Molecular Conformation Molecular Target Mus Mutation Nature Output PKD1 gene PKD2 gene PKD2 protein Pathogenesis Pathway interactions Polycystic Kidney Diseases Protein Family Protein Subunits Proteins Renal function Renal tubule structure Reporting Research Personnel Role Signal Pathway Signal Transduction Testing Tubular formation base conditional knockout extracellular in vivo inhibitor insight mouse model mutant nephrogenesis new therapeutic target novel polycystic kidney disease 1 protein predictive modeling prevent promoter protein transport public health relevance renal epithelium response trafficking

项目摘要

Abstract Autosomal dominant polycystic kidney disease (ADPKD) is characterized by the development of fluid-filled sacs called cysts in both kidneys, but key signals that cause cyst formation are unknown. Multiple downstream cellular pathways are dysregulated during cystogenesis. However, targeting these pathways has limited effects on ADPKD treatment. ADPKD is caused by mutations in genes encoding for polycystin-1 (PC1) and polycystin-2 (PC2). Both polycystins localize to primary cilia. The primary cilium instructs cellular decisions in response to extracellular inputs by compartmentalizing subcellular signaling. However, the role of primary cilium in kidney cystogenesis is inherently complex. Loss of polycystins causes severe cystogenesis, which is mostly cilia- dependent, while loss of cilia by itself causes smaller cysts. These results suggest that a complex interplay between counter-regulatory positive and negative signals in cilia inhibit cyst formation in normal renal tubules and promote cyst growth in ADPKD, respectively. Identifying these signals could have profound impacts on novel therapeutic targets and strategies for ADPKD. However, uncoupling ciliary signals causing cystogenesis from downstream signaling pathways affected during cystogenesis and the difficulty in identification of ciliary signals in absence of cilia have prevented their identification. Here, by studying the ciliary trafficking adapter, tubby family protein Tulp3, we aim to identify and target the key upstream ciliary signals that regulate cystogenesis. We previously showed that Tulp3 functions in ciliary trafficking of membrane proteins without affecting respective protein levels or disrupting cilia by coupling to the intraflagellar transport complex A (IFT-A). We recently showed that embryonic kidney-specific conditional knockouts of Tulp3 developed renal cystogenesis that was less severe than from polycystin loss. Concomitant Tulp3 loss did not inhibit cystogenesis upon PC1 loss, unlike ciliary disruption, but caused early lethality, suggesting accelerated loss of renal function. These results further reinforce the polycystin independent inhibitory role of ciliary proteins in cystogenesis. Other groups have reported suppression of cystogenesis in adult mouse models of PKD from Tulp3 or IFT-A loss. Thus, we hypothesize that Tulp3-regulated ciliary cargoes determine cilia-dependent cyst inhibition during development and PC1/2- inhibited cilia-dependent cyst activation in adults. Here by leveraging our expertise in ciliary trafficking and signaling and using novel mouse models to block trafficking of potential cargo subtypes, we propose to identify ciliary regulators of cystogenesis. In Aim 1, we will determine novel Tulp3 trafficked ciliary cargoes and signaling outputs in cilia relevant to cystogenesis. In Aim 2, we will determine Tulp3 regulated cyst inhibitory ciliary cargo subtypes that genetically synergize with PC1 during murine kidney development. In Aim 3, we will test Tulp3 cargo subtypes as promoters of cystogenesis in adult mouse models of PKD in vivo using genetic epistasis. Our approach will determine dual ciliary drivers impacting cystogenesis in vivo during adult-onset ADPKD and embryonic-onset cystic disease unraveling the molecular nature of cilium-generated signaling in either setting.

抽象的常染色体显性多囊性肾脏疾病（ADPKD）的特征是液体填充囊的发展在两个肾脏中称为囊肿，但引起囊肿形成的主要信号尚不清楚。多个下游细胞囊肿发生过程中途径失调。但是，针对这些途径对 ADPKD处理。 ADPKD是由编码polycystin-1（PC1）和Polycystin-2的基因突变引起的（PC2）。两种多囊菌都定位于原发性纤毛。主要的纤毛响应于细胞外输入通过分隔亚细胞信号传导。但是，原发性纤毛在肾脏中的作用膀胱遗传学本质上是复杂的。多囊菌素的丧失会导致严重的囊肿发生，这主要是纤毛依赖，而纤毛的损失本身会导致较小的囊肿。这些结果表明复杂的相互作用纤毛中的反调节正和负信号之间抑制正常肾小管的囊肿形成分别促进ADPKD的囊肿生长。识别这些信号可能会对小说产生深远的影响 ADPKD的治疗目标和策略。但是，解开睫状信号，导致囊肿发生在囊肿发生过程中影响的下游信号通路和识别睫状信号的难度在缺乏纤毛的情况下，已经阻止了他们的识别。在这里，通过研究睫毛贩运适配器，Tubby 我们旨在识别和靶向调节囊肿发生的关键上游睫状信号的家族蛋白质tulp3。我们先前表明Tulp3在膜蛋白的睫状运输中起作用而不影响各自蛋白质水平或通过耦合到flagellar运输复合物A（IFT-A）来破坏纤毛。我们最近显示 Tulp3的胚胎肾脏特异性有条件敲除肾脏囊肿发生，这不那么严重而不是来自多囊丢失。与睫状相比破坏，但引起早期致死性，表明肾功能的丧失加速。这些结果进一步增强纤毛蛋白在囊肿发生中的多囊蛋白独立抑制作用。其他小组报告了从TULP3或IFT-A损失中抑制PKD的成年小鼠模型中的囊肿发生。因此，我们假设 Tulp3调节的睫状货物确定开发过程中纤毛依赖性囊肿的抑制作用和PC1/2-- 抑制成人纤毛依赖性囊肿活化。在这里利用我们在睫毛贩运方面的专业知识和信号传导和使用新型的小鼠模型阻止了潜在货物亚型的运输，我们建议识别囊肿发生的睫状调节剂。在AIM 1中，我们将确定新颖的Tulp3被运输的纤毛货物和信号传导纤毛的输出与囊肿发生有关。在AIM 2中，我们将确定TULP3调节的囊肿抑制性睫状货物在鼠肾脏发育过程中，基因与PC1协同作用的亚型。在AIM 3中，我们将测试Tulp3 货物亚型用遗传性遗传学在体内的成年小鼠模型中作为囊肿发生的启动子。我们的方法将确定成人发作ADPKD和胚胎发作的囊性疾病在任何一种情况下都会揭示纤毛生成信号的分子性质。