Regulation of Apical Specific Endocytosis in the C. elegans Intestine

描述（由申请方提供）：我们在该提案中的目标是鉴定和理解将内吞货物从顶端质膜内化和转运至肠上皮细胞（肠细胞）溶酶体的细胞组分。许多上皮细胞表面受体、离子通道和其他与人类疾病有关的膜整合蛋白特异性地定位于顶膜。它们在顶端表面上的稳态丰度在很大程度上受它们通过分泌和内吞作用从质膜插入和移除的相对速率控制。为了获得对驱动这一途径的机制的新见解，我们建议开创性地使用显微镜下的线虫C。Elegans为这些研究。我们将利用该系统独特的实验功能，为该研究领域创建一个新的，高度简化的，可遗传操作的范式。C语言的主要特点是：在现代生物学研究的几乎所有领域中，秀丽隐杆线虫是一种领先的模式生物，其高度先进的遗传学包括极其容易的基因敲除、敲除和转基因技术，加上透明的身体，该身体允许在完整的活生物体的生理学相关背景中可视化荧光标记的分子。我们的初步研究已经发现了一种新的调控途径，通过Rac 1/CED-10控制顶端内吞作用。进一步的分析将剖析该途径控制顶端内吞作用的机制。此外，我们计划应用C中可用的独特遗传工具。elegans以鉴定与哺乳动物保守的顶端内吞作用的另外的调节剂。作为最简单的具有真肠上皮的动物模型，C. elegans具有回答关于顶端肠功能机制的关键问题的潜力，并且可以提供催化未来对哺乳动物肠上皮中高度相关的通路的研究的关键框架。公共卫生相关性。我们的目标是在这个建议是确定和理解的细胞成分，内化和运输大分子从顶端质膜的溶酶体的肠上皮细胞（肠上皮细胞）。与人类疾病有关的许多重要蛋白质通过内吞作用从顶膜特异性摄取，内吞作用在肠上皮细胞中特化，并显示出与其他类型细胞中相关过程的重要差异。因此，这项研究将与营养摄取，液体稳态和痢疾，胎儿抗体转运。

DESCRIPTION (provided by applicant): Our goal in this proposal is to identify and understand the cellular components that internalize and transport endocytic cargo from the apical plasma membrane to the lysosomes of intestinal epithelial cells (enterocytes). Many epithelial cell surface receptors, ion channels, and other integral membrane proteins implicated in human disease are specifically localized to the apical membrane. Their steady-state abundance on the apical surface is largely controlled by their relative rates of insertion and removal from the plasma membrane by secretion and endocytosis. To gain new insight into the mechanisms that drive this pathway, we propose to pioneer the use of the microscopic nematode worm C. elegans for these studies. We will take advantage of the unique experimental features of this system, creating a new, highly simplified, and genetically manipulatable paradigm for this research area. Chief among the features that have made C. elegans a leading model organism in nearly all areas of modern biological research are its highly advanced genetics, including extremely facile gene knockdown, knockout, and transgenic technology, coupled with a transparent body that allows visualization of fluorescently tagged molecules in the physiologically relevant context of the intact living organism. Our preliminary studies have already uncovered a novel regulatory pathway controlling apical endocytosis through Rac1/CED-10. Further analysis will dissect the mechanisms by which this pathway controls apical endocytosis. In addition, we plan to apply the unique genetic tools available in C. elegans to identify additional regulators of apical endocytosis conserved with mammals. As the simplest animal model possessing a true intestinal epithelium, C. elegans has the potential to answer key questions regarding the mechanism of apical intestinal function, and can provide a key framework that catalyzes future investigation into the highly related pathways in mammalian intestinal epithelia. PUBLIC HEALTH RELEVANCE. Our goal in this proposal is to identify and understand the cellular components that internalize and transport macromolecules from the apical plasma membrane to the lysosomes of intestinal epithelial cells (enterocytes). Many important proteins implicated in human disease are specifically taken up from the apical membrane by endocytosis, which is specialized in enterocyte cells, and displays important differences from related processes in other types of cells. Thus this research will be relevant to nutrient uptake, fluid homeostasis and dysentery, and fetal antibody transport.