REGULATION OF NORMAL AND CYSTIC RENAL TUBULOGENESIS

正常和囊性肾管发生的调节

• 批准号: 3247050
• 负责人: W. James Nelson
• 金额: $ 20.04万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-30 至 1997-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3247050
• 关键词: MDCK cell; active sites; adenosinetriphosphatase; cell adhesion molecules; cell cell interaction; cell differentiation; cell growth regulation; confocal scanning microscopy; embryo /fetus tissue /cell culture; enzyme induction /repression; epithelium; gene expression; glycosphingolipids; growth factor; immunocytochemistry; in situ hybridization; laboratory mouse; mammalian embryology; membrane lipids; mesenchyme; mixed tissue /cell culture; ouabain; pathologic process; polycystic kidney; renal tubule

Developmental abnormalities in renal tubule morphogenesis and function are characteristic of polycystic kidney disease, a major genetic disorder in humans that affects over 500,000 people in the United Stats. The cause of the disease is unknown, but it has been postulated that increased cell proliferation and altered transtubular fluid transport are important. Our long term objectives are to understand the morphoregulatory mechanisms involved in the development of normal renal tubule epithelia organization, and to determine whether these mechanisms are altered during development of polycystic kidney disease. We have established in vitro methods to analyze renal epithelial cell development (Transfilter Cultures), and the role of candidate morphogenetic factors in tubulogenesis that will be extended to analyze cells from cystic tubule epithelia of cpk mice, a murine model of polycystic kidney disease. Our preliminary studies show that in early development Na/K-ATPase is transiently localized to the apical membrane domain of normal cells, but is continuously expressed on the apical membrane in cystic epithelial cells. Our previous results indicate that the normal distribution of Na/K-ATPase at the basal-lateral membrane is generated by cell-cell contact and interactions with the membrane- cytoskeleton and membrane lipids. We will test the hypothesize that abnormal regulation of soluble factors that induce tubulogenesis in development could lead to increased cell proliferation of tubular epithelia and, combined with the retention of active Na/K-ATPase on the apical membrane, the formation of cystic tubules: 1. Define the temporal and spatial regulation of Na/K-ATPase distribution following mesenchyme induction and conversion to epithelial cells during normal development. Patterns of expression and distribution of Na/K- ATPase, membrane-cytoskeleton, and membrane lipids will be determined. 2. Modulate the timing of E-cadherin-induced cell-cell interactions during mesenchyme conversion and epithelial cell differentiation. Effects of inhibiting cell-cell contacts on cell differentiation and tubulogenesis during metanephrogenic mesenchyme induction and conversion in culture will be analyzed. 3. Investigate mesenchyme induction and epithelial cell differentiation in transfilter cultures from metanephroi of CPK mice. Patterns of expression and distribution of Na/K-ATPase, membrane-cytoskeleton, and membrane lipids will be determined and compared temporally and spatially to those in normal development. 4. Analyze the expression and function of soluble factors, that regulate tubulogenesis in vitro, on normal and cystic epithelial cell differentiation and tubulogenesis. Expression and function of Scatter Factor/Hepatocyte Growth Factor (SC/HGF), a potent inducer of tubulogenesis in renal epithelial cells in vitro, will be examined in cultures of developing renal tubules from normal and cystic metanephroi, and in purified populations of normal and cystic epithelial cells induced to form branching tubular networks in vitro.

肾小管形态发生和功能的发育异常是 多囊性肾脏疾病的特征，这是一种主要的遗传疾病 在联合统计数据中影响超过500,000人的人类。 原因 该疾病尚不清楚，但已经假定细胞增加 增殖和改变的三叶液转运很重要。 我们的 长期目标是了解形态调节机制 参与正常肾小管上皮组织的发展， 并确定在开发过程中是否改变了这些机制 多囊肾。 我们已经建立了体外方法来分析 肾上皮细胞发育（转滤剂培养）和 候选的肾变发生中的形态发生因子将扩展到 分析来自CPK小鼠囊性小管上皮的细胞，这是一种鼠模型 多囊肾。 我们的初步研究表明，早期 开发Na/k-ATPase瞬时位于顶端膜 正常细胞的域，但在顶端连续表达 囊性上皮细胞中的膜。 我们先前的结果表明 基底膜上Na/k-ATPase的正态分布为 通过细胞 - 细胞接触以及与膜的相互作用产生 细胞骨架和膜脂质。 我们将测试假设的 异常调节可溶性因子，诱导微管发生 发育可能导致肾小管上皮的细胞增殖增加 并与在顶端保持活性Na/k-ATPase的保留率 膜，囊性小管的形成： 1。定义Na/k-ATPase分布的时间和空间调节 遵循间质诱导并转化为上皮细胞 正常发展。 Na/k-的表达和分布模式 将确定AT​​Pase，膜细胞骨架和膜脂质。 2。调节电子钙粘蛋白诱导的细胞 - 细胞相互作用的时间 间质转化和上皮细胞分化。 效果 抑制细胞细胞的接触细胞分化和微管发生 在养生过程中，间充质诱导和培养中的转化将 可以分析。 3。研究间质诱导和上皮细胞分化 来自CPK小鼠的元素的转卵器培养物。 表达模式 Na/k-ATPase，膜细胞骨架和膜脂质的分布 将确定并在时间和空间上与正常状态进行比较 发展。 4。分析调节可溶性因子的表达和功能 在正常和囊性上皮细胞上体外微管发生 分化和微管发生。 散布的表达和功能 因子/肝细胞生长因子（SC/HGF），是肾变发生的有效诱导剂 在体外肾上皮细胞中，将在 从正常和囊性元素开发肾小管，在 诱导形成的正常和囊性上皮细胞的纯化群体 体外分支管网。