CELLULAR BIOLOGY OF RENAL FUNCTION AND DISEASE

本计划项目的目的是研究细胞 肾上皮细胞膜功能和功能障碍的生物学 和肾小球细胞。 战略将是使用聚合， 先进的超微结构免疫化学技术，冷冻- 骨折，分子生物学，生物物理学和生物化学， 探索不同细胞类型中相互关联的问题。 具体来说，膜回收和微丝的影响 将检查对加压素诱导的水流的调节。 我们将研究网格蛋白包被的小凹和小泡在 膜水通道的再循环，并试图 分离、纯化和表征水通道蛋白。 的 跨上皮水流中微丝相互作用 将在完整细胞中进行研究，并与体外 系统将评估纯化的肌动蛋白和肌动蛋白相关的 蛋白质相互作用及其经历凝胶-溶胶的能力 在存在和不存在渗透梯度的情况下转化。 特定蛋白质（H+ ATP酶）的膜再循环将被 在质子分泌细胞中检查，利用 H+ ATP酶单克隆抗体。 的关系 H+ ATP酶分子与其他膜特征， 包括通过独特的非网格蛋白包被的囊泡转运， 考察 这些研究将得到以下研究的补充： 肾细胞功能障碍。 的细胞和分子 Heymann发病机制中涉及的抗原生物学 将检查肾炎，以确定如何脱落与 致肾炎抗原gp 330的内吞作用在 肾小球上皮细胞 肾小球系膜细胞功能 将通过确定炎症介质是否 激活系膜细胞的钙反应， 促进收缩、增殖和前列腺素类产生 这可能与糖尿病肾病中的类似现象有关。 通过探测一些一般的细胞生物学过程 与细胞膜的动态调节密切相关 功能，我们希望相互作用可以定义在分子 水平 本研究提案中涉及的所有项目均 这个共同的主题。 很可能细胞中的一些问题 生物学是正常和异常细胞功能的关键， 回答，提高我们对肾功能的理解， 疾病

The aim of this Program Project is to investigate the cellular biology of membrane function and dysfunction in renal epithelial and glomerular cells. The strategy will be to use convergent, advanced techniques in ultrastructural immunochemistry, freeze- fracture, molecular biology, biophysics and biochemistry to explore interrelated problems in different cell types. Specifically, membrane recycling and the effect of microfilament modulation on vasopressin-induced water flow will be examined. We will investigate the role of clathrin coated pits and vesicles in the recycling of membrane water channels, and attempt to isolate, purify and characterize the water channel protein(s). The interactive role of microfilaments in transepithelial water flow will be studied in intact cells and correlations made with in vitro systems which will evaluate purified actin and actin-associated protein interactions and their ability to undergo gel-sol transformation in the presence and absence of osmotic gradients. Membrane recycling of a defined protein, the H+ATPase, will be examined in proton secreting cells, taking advantage of a monoclonal antibody against H+ATPase. The relationship of H+ATPase molecules to other characteristic membrane features, including transport by unique nonclathrin coated vesicles, will be examined. These studies will be complemented by studies on cellular dysfunction of renal cells. The cellular and molecular biology of antigens involved in the pathogenesis of Heymann nephritis will be examined to determined how shedding versus endocytosis of a nephritogenic antigen, gp330, is achieved in glomerular epithelial cells. Glomerular mesangial cell function will be probed by determining if mediators of inflammation activate a calcium response in the mesangial cell, which in turn promotes contraction, proliferation, and prostanoid production that can be related to similar phenomona in diabetic nephropathy. By probing a number of general cell biological processes intimately involved with the dynamic regulation of membrane function, we hope to interactions can be defined at the molecular level. All of the projects involved in this research proposal share this common theme. It is likely that a number of problems in cell biology which are key to normal and abnormal cell function will be answered, enhancing our understanding of renal function and disease.