Wnt5a and Planar Cell Polarity in Kidney Development and Cyst formation

Wnt5a 和平面细胞极性在肾脏发育和囊肿形成中的作用

• 批准号: 8694353
• 负责人: Liwei Huang
• 金额: $ 12.97万
• 依托单位: EASTERN VIRGINIA MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-15 至 2017-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8694353
• 关键词: Adult; Affect; American; Animal Model; Apical; Autosomal Dominant Polycystic Kidney; Autosomal Recessive Polycystic Kidney; Cell Polarity; Cell model; Cell physiology; Cells; Chromosome Mapping; Cilia; Complex; Cyst; Cystic Kidney Diseases; Cystic kidney; Development; Disease; Drosophila genus; Embryo; Epithelial; Epithelial Cells; Epithelium; Family; Gene Activation; Gene Expression; Gene Proteins; Genes; Glycoproteins; Goals; Hereditary Disease; Homeostasis; Human; In Vitro; Kidney; Knock-out; Link; Liquid substance; Locales; Location; MAPK8 gene; MDCK cell; Measures; Membrane Proteins; Mentors; Messenger RNA; Modeling; Molecular; Mus; Nuclear; Organ; Organelles; Pathogenesis; Pathway interactions; Pattern; Phenotype; Play; Proliferating; Proteins; Regulation; Renal tubule structure; Research Project Grants; Role; Secretory Component; Sensory; Signal Pathway; Signal Transduction; Signaling Molecule; Surface; Testing; Therapeutic Intervention; Time; Tissues; Tubular formation; Vesicle; Wnt proteins; Work; cilium biogenesis; design; functional group; in vivo; nephrogenesis; novel; overexpression; receptor; research study; rho GTP-Binding Proteins; trans-Golgi Network

DESCRIPTION (provided by applicant): Cysts are "building blocks" for epithelial organs, such as the kidney, and abnormal regulation of cystogenesis results in disorders such as autosomal dominant polycystic kidney disease (ADPKD). ADPKD, affecting 500,000 Americans, is the most common potentially lethal genetic disease. The primary cilium, an organelle projecting from the apical surface, has been strongly implicated in ADPKD pathogenesis and is thought to act as a sensory antenna that transmits information regarding flow dynamics to the cell. When primary cilia of renal tubule cells are disrupted, the cells, through a still unclear mechanism, misinterpret this as a signal to dedifferentiate and proliferate, resulting in the formation of lare cysts that destroy the kidney. The goal here is to understand the role of the highly conserved eight-protein exocyst complex in kidney development, especially how the exocyst interacts with Wnt proteins. The exocyst is a critical component of the secretory pathway, shuttling vesicles containing membrane proteins from the trans-Golgi network to targeted subcellular locales, including primary cilia. Sec10, in turn, is a critical component of the exocyst. The Lipschutz Lab (the mentor's lab) has shown through in vitro studies of renal tubule cells that Sec10 is critical for proper formation of both primary cilia and cysts. In addition, it was shown in human ADPKD cells that the exocyst is mislocalized intracellularly, thereby establishing a link between exocyst location and ADPKD. Wnt genes encode a large, highly conserved family of secreted glycoproteins that play essential roles in controlling tissue patterning, cell fate, and proliferaton from drosophila to humans. Vertebrate Wnts have been divided into two functional groups by reference to their downstream signaling pathways. The canonical Wnts signal through nuclear 2-catenin/TCF-LEF while the noncanonical Wnts function through alternate signaling cascades that include Ca2+/PKC and RhoA/JNK. The canonical Wnt pathway is necessary for adult kidney homeostasis, and abrogation of this signaling leads to cystic kidney disease. The Lipschutz Lab showed that Rho GTPases regulate the exocyst, and Preliminary Studies show Wnt and exocyst mRNA co-expression during kidney development, as well as differential Wnt expression following Sec10 knockdown in vitro. The hypothesis we propose testing is that Wnt genes work with the exocyst to regulate kidney development, especially ciliogenesis and cystogenesis. Accordingly, we will use embryonic mouse kidneys to examine spatial-temporal exocyst and Wnt expression patterns during development (Aim 1). We will then use in vitro renal epithelial cell models to characterize the molecular pathways by which the exocyst and Wnts interact (Aim 2). Finally, we will study the role of the exocyst in regulating kidney development and Wnt signaling in vivo utilizing kidney- specific Sec10-overexpressing, Sec10 knockout, and Pkd2WS25/WS183 mice, representing an outstanding animal model of ADPKD (Aim 3). Successful completion of these experiments will result in the identification of novel candidate targets for therapeutic intervention in ADPKD, a disease for which no approved treatments exist.

描述（由申请人提供）：囊肿是上皮器官（如肾脏）的“构建块”，囊肿发生的异常调节可导致常染色体显性多囊肾病（ADPKD）等疾病。影响50万美国人的ADPKD是最常见的潜在致命遗传疾病。初级纤毛是一种从根尖表面突出的细胞器，与ADPKD的发病密切相关，被认为是一种感觉天线，将有关血流动力学的信息传递给细胞。当肾小管细胞的初级纤毛被破坏时，细胞通过一种尚不清楚的机制将其误解为去分化和增殖的信号，从而形成破坏肾脏的大囊肿。本研究的目的是了解高度保守的8蛋白胞囊复合物在肾脏发育中的作用，特别是胞囊如何与Wnt蛋白相互作用。外囊是分泌途径的重要组成部分，将含有膜蛋白的囊泡从反式高尔基体网络运送到目标亚细胞部位，包括初级纤毛。Sec10，反过来，是囊泡的关键组成部分。Lipschutz实验室（导师的实验室）通过对肾小管细胞的体外研究表明，Sec10对于原发性纤毛和囊肿的正常形成至关重要。此外，在人ADPKD细胞中显示，胞囊在细胞内定位错误，从而建立了胞囊之间的联系