Endocytosis and Recycling in C. elegans and Mammals

线虫和哺乳动物的内吞作用和回收

基本信息

批准号：
8295591
负责人：
Barth Demian Grant
金额：
$ 34.26万
依托单位：
RUTGERS, THE STATE UNIV OF N.J.
依托单位国家：
美国
项目类别：
财政年份：
2003
资助国家：
美国
起止时间：
2003-05-05 至 2016-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8295591
关键词：
Adipocytes Affect Architecture Area Binding Biological Models Biological Process Blood Glucose Caenorhabditis elegans Caenorhabditis elegans Proteins Cell Polarity Cell membrane Cell surface Cells Cellular biology Complex Cytokinesis Cytoskeleton Data Defect Disease Early Endosome Elements Endocytosis Endosomes Epithelial Cells Epithelium Etiology Event Feedback Gap Junctions Genetic Glucose Transporter Grant Growth Factor Receptors Guanine Nucleotide Exchange Factors Guanosine Triphosphate Guanosine Triphosphate Phosphohydrolases Homologous Gene Human Immune response In Vitro Insulin Intervention Intestines Link Lipids MDCK cell Maintenance Malignant Neoplasms Mammalian Cell Mammals Mediating Membrane Membrane Protein Traffic Microbe Microscopy Modeling Molecular Monomeric GTP-Binding Proteins Motor Movement Nematoda Nervous system structure Non-Insulin-Dependent Diabetes Mellitus Nutrient Pathway interactions Phylogenetic Analysis Play Process Protein Family Proteins Publishing Recycling Regulation Research Role Sorting - Cell Movement Synaptic plasticity System Techniques Testing Time Tissues Transmembrane Transport Work Yeasts amphiphysin base cancer type cell motility combat countercurrent chromatography design in vivo insight macromolecule man mutant new therapeutic target novel protein function protein transport rab GTP-Binding Proteins receptor recycling research study synaptogenesis therapeutic target trafficking uptake

项目摘要

DESCRIPTION (provided by applicant): Cells and tissues establish and maintain their unique architectures in large part through the tight regulation of protein and membrane transport. One key aspect of this process is endocytic recycling, the selective return of internalized macromolecules to the cell surface from endosomes. Understanding endocytic recycling is of fundamental importance to cell biology and has broad relevance to many areas of biomedicine including cancer and type II diabetes. Our general approach has been to exploit powerful features of C. elegans genetics to characterize proteins that are required for the recycling process in vivo. We then extend these findings to mammalian cells and to in vitro analysis of the relevant C. elegans proteins and their mammalian homologs. For many of these studies we focused on a system that we pioneered, the C. elegans intestine, a very simple model that allows facile analysis of endocytic membrane transport pathways within intact polarized epithelia. During the previous granting period we gained new understanding of how RME-1/EHD family proteins, identified in our previous screens, function in endosomal membrane tubulation and fission, and identified new proteins that function with RME-1 in this process. We also identified and characterized several new effectors for the small GTPase RAB-10/Rab10, a protein that we previously showed is a master regulator of basolateral recycling in the worm intestine and polarized mammalian MDCK cells. We propose three new aims to further elucidate the molecular mechanisms underlying endocytic recycling. We plan to decipher a novel inhibitory cascade regulating early endosome GTPase RAB-5 during receptor recycling. New data indicates regulation by recycling endosome proteins RAB-10, CED-10/Rac, and AMPH-1/Amphiphysin. We will also elucidate the molecular links of newly identified RAB-10 effector EHBP-1 to membranes, the cytoskeleton, and apparent feedback regulation of RAB-10. Finally, we focus on understanding the molecular basis of endosomal regulation by a new player in the RAB-10 pathway, putative ARF6 effector UNC-16/ JIP3. We connect UNC-16 to an ARF-GAP in this pathway and to a new Rab-GTPase regulator. The experiments proposed here should provide significant new insights into how endocytic recycling works. Given the high level of phylogenetic conservation of such pathways from worms to mammals, and our parallel analysis in human cells, we expect that our work will provide extensive insight into key conserved elements relevant across species. This work is important for understanding disease etiology and in identifying therapeutic targets for disease intervention. PUBLIC HEALTH RELEVANCE: Our research focuses on the return of internalized macromolecules to the cell surface from endosomes (endocytic recycling), a basic cell biological process that is of fundamental importance to many areas of biomedicine. For instance, endocytic recycling is a key control point in the insulin-stimulated movement of glucose transporters (Glut4) from endosomes to the plasma membrane, a process that goes awry in type II diabetes. A better understanding of how endocytic recycling functions will be profoundly important in identifying therapeutic targets to combat this and other diseases.

描述（由申请人提供）：细胞和组织通过严格的蛋白质和膜转运来建立和维护其独特的建筑。该过程的一个关键方面是内吞回收，这是内部大分子从内体中从内体表面的选择性返回。了解内吞回收对细胞生物学至关重要，并且与包括癌症和II型糖尿病在内的许多生物医学领域具有广泛的相关性。我们的一般方法是利用秀丽隐杆线虫遗传学的强大特征来表征体内回收过程所需的蛋白质。然后，我们将这些发现扩展到哺乳动物细胞，并对相关的秀丽隐杆线虫蛋白及其哺乳动物同源物进行体外分析。对于许多研究，我们集中在我们开创的秀丽隐杆线虫肠道上的系统上，这是一个非常简单的模型，可轻松分析完整偏振上皮的内吞膜传输途径。在上一个授予期间，我们对RME-1/EHD家族蛋白（在我们先前的筛选中识别，在内体膜管中的功能和裂变中的功能）有了新的了解，并在此过程中鉴定了与RME-1一起起作用的新蛋白质。我们还确定并表征了小型GTPase RAB-10/RAB10的几个新效应子，这是我们先前显示的蛋白质是蠕虫肠和偏振哺乳动物MDCK细胞中基底外侧回收的主要调节剂。我们提出了三个新的目标，以进一步阐明内吞回收基础的分子机制。我们计划破译一种新型的抑制性级联反应，以调节受体回收过程中早期内体GTPase RAB-5。新数据表明通过回收内体蛋白RAB-10，CED-10/RAC和AMPH-1/Amphiphysin进行调节。我们还将阐明新鉴定的RAB-10效应子EHBP-1与膜，细胞骨架以及RAB-10的明显反馈调节的分子联系。最后，我们专注于理解RAB-10途径，推定的ARF6效应器UNC-16/ JIP3的新玩家内体调节的分子基础。我们将UNC-16连接到该途径中的ARF-GAP和新的RAB-GTPase调节器。这里提出的实验应提供有关内吞回收如何工作的重要新见解。鉴于从蠕虫到哺乳动物的这种途径的系统发育量很高，并且我们在人类细胞中的平行分析，我们希望我们的工作将为各种物种相关的关键保守元素提供广泛的见解。这项工作对于理解疾病的病因和确定疾病干预的治疗靶点很重要。公共卫生相关性：我们的研究重点是内部大分子从内体（内吞回收）回归细胞表面，这是一种基本的细胞生物学过程，对许多生物医学领域至关重要。例如，内吞回收是葡萄糖转运蛋白（GLUT4）从内体到质膜的胰岛素刺激运动中的一个关键控制点，这一过程在II型糖尿病中会了。更好地理解内吞回收功能如何在识别与这种疾病和其他疾病作斗争的治疗靶标方面非常重要。