Pathogenesis of PKD in Mice Lacking Renal Cilia

缺乏肾纤毛的小鼠多囊肾的发病机制

• 批准号: 7373619
• 负责人: Peter Igarashi
• 金额: $ 34.06万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-03-01 至 2009-09-15
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7373619
• 关键词: Address; Adult; Animal Model; Apical; Apoptosis; Birth; CDKN1A gene; Calcium; Cell Differentiation process; Cell Line; Cell Nucleus; Cell Proliferation; Cells; Cilia; Cultured Cells; Cyst; Cystic kidney; Cytosol; Decompression Sickness; Disease; Epidermal Growth Factor Receptor; Epithelial; Epithelial Cells; Epithelial cyst; Exhibits; Exons; Family; Genes; Genetic; Genetic Recombination; Goals; Hair; Human; In Vitro; KRP protein; Kidney; Kidney Failure; Kinesin; Liquid substance; Localized; Measures; Molecular; Morphology; Motor; Mus; Mutant Strains Mice; Mutation; Organ; Organelles; PKD2 protein; Pathogenesis; Pathway interactions; Phenotype; Polycystic Kidney Diseases; Proteins; Regulation; Renal function; Renal tubule structure; Research Personnel; Role; Severities; Signal Pathway; Signal Transduction; Surface; Testing; Transgenic Mice; beta catenin; cell growth; cell growth regulation; day; fluid flow; in vivo; mouse model; mutant; oncoprotein p21; polycystic kidney disease 1 protein; postnatal; programs; response; shear stress

DESCRIPTION (provided by applicant): Polycystic kidney disease (PKD), the most common genetic cause of renal failure in humans, is characterized by the accumulation of fluid-filled cysts in the kidneys and other epithelial organs. Although the genes that cause PKD have been identified, the mechanism of cyst formation remains unclear. Recent studies suggest that PKD may arise from abnormalities of the primary cilium, an immotile, hair-like organelle that project from the apical surface of most renal epithelial cells. To test this hypothesis, Cre/loxP recombination was used to delete the Kif3a gene in the kidneys of transgenic mice. Kif3a (Kinesin family 3a) encodes the 80/85-kda subunit of the kinesin-II motor protein that is essential for cilia formation. Kidney-specific deletion of Kif3a results in viable offspring with normal-appearing kidneys at birth. Renal cysts begin to appear at postnatal day (P)5, and renal failure develops by P21. The cyst epithelial cells lack primary cilia and have abnormalities in cell proliferation, apoptosis, polarity, and (-catenin localization. The overall goal of this project is to understand how the loss of renal cilia leads to cyst formation. Inducible Cre/loxP recombination will be used to delete Kif3a in adult mice to test whether the loss of primary cilia in mature renal tubules produces PKD. Cyst epithelial cell lines established from Kif3a mutant mice will be examined for abnormalities in cilia formation, proliferation, and differentiation. The mechanism of increased proliferation will be elucidated, focusing on activation of the beta-catenin signaling pathway. The expression and subcellular localization of polycystin-1 and polycystin-2 will be examined, and the phenotype of mice with combined mutations of Kif3a and either Pkd1 or Pkd2 will be studied to determine whether Kif3a is in the same pathway of cyst formation as Pkd1 and Pkd2. Kif3a mutant cells that lack primary cilia will be exposed to fluid shear stress to elucidate the role of renal cilia in the flow-dependent regulation of intracellular calcium. Taken together, the characterization of a new mouse model of PKD promises to advance our understanding of the molecular pathogenesis of human cystic diseases and the essential role of primary cilia in regulating cell growth and differentiation.

描述（由申请人提供）：多囊性肾脏疾病（PKD）是人类肾衰竭的最常见遗传原因，其特征在于肾脏和其他上皮器官中充满液体的囊肿的积累。尽管已经确定了引起PKD的基因，但囊肿形成的机理尚不清楚。最近的研究表明，PKD可能来自原发性纤毛的异常，这是一种来自大多数肾上皮细胞的顶部表面的immotile，头发样细胞器。为了检验该假设，使用CRE/LOXP重组来删除转基因小鼠肾脏中的KIF3A基因。 KIF3A（动力蛋白家族3A）编码对纤毛形成至关重要的驱动蛋白II运动蛋白的80/85-kDa亚基。 KIF3A的肾脏特定缺失导致出生时正常肾脏的可行后代。肾脏囊肿开始在产后（P）5开始出现，肾衰竭由P21发展。囊肿上皮细胞缺乏原发性纤毛，并且在细胞增殖，细胞凋亡，极性和（ - 卡替宁定位。用于删除成年小鼠中的KIF3A，以测试成熟的肾小管中的原代纤毛是否会产生PKD。将阐明增殖，重点是β-catenin信号传导途径的激活。研究以确定KIF3A是否与PKD1和PKD2的囊肿形成相同的途径。综上所述，新的PKD小鼠模型的表征有望促进我们对人囊性疾病的分子发病机理的理解，以及原代纤毛在调节细胞生长和分化中的重要作用。