Genetic proteomic and functional analysis of junctional complexes in Drosophila

我们的身体依赖于我们的屏障上皮的完整性;细胞片（如皮肤，肠道，肺）将我们与外部世界分开，或将我们身体的不同区域分开。这种上皮中的数千个细胞具有高度专门化的连接，将它们拉在一起，以防止泄漏（“紧密”上皮）或仅允许特定溶质的流动（“泄漏”上皮）。这种完整性的问题可能是严重的或致命的（例如腹膜炎，多发性硬化症，肾脏疾病）。是什么使连接紧密或泄漏？在连接中发现的许多蛋白质是已知的。然而，除了一些人类遗传疾病和少数“敲除”小鼠品系之外，很难区分每种蛋白质的贡献。我们建议研究的模式昆虫，果蝇的肾脏中的隔膜连接（同源的脊椎动物的“紧密”连接）。这是一个理想的系统，因为我们可以便宜而快速地干预我们选择的细胞中的基因功能。我们将使用蛋白质组学来识别连接中的主要蛋白质，然后突变蛋白质组学结果所涉及的基因，并研究连接是否保持紧密或变得泄漏。这将允许对构成连接的蛋白质的相对作用进行全面研究。

Our bodies rely on the integrity of our barrier epithelia; the sheets of cells (like skin, gut, lung) that separate us from the outside world, or keep different regions of our bodies apart. The thousands of cells in such epithelia have highly specialised junctions that zip them together, in order to prevent leakage (a 'tight' epithelium) or to permit flux of only specific solutes (a 'leaky' epithelium). Problems with this integrity can be serious or fatal (e.g. peritonitis, multiple sclerosis, kidney disease). What makes a junction either tight or leaky? Many of the proteins that are found in junctions are already known. However, with the exceptions of some human genetic diseases and a few 'knockout' mouse lines, it is hard to tease apart the contributions of each protein. We propose to study the septate junction (the homologue of the vertebrate 'tight' junction) in the kidney of the model insect, Drosophila melanogaster. This is an ideal system, because we can cheaply and quickly intervene in gene function in cells of our choice. We will use proteomics to identify the major proteins in the junction, then mutate the genes implicated by the proteomics results, and study whether the junctions remain tight, or become leaky. This will allow a comprehensive study of the relative roles of the proteins that make up the junction.