CONTROL OF MEMBRANE TRAFFIC IN REGULATED SECRETORY CELLS

调节分泌细胞中膜流量的控制

• 批准号: 2177807
• 负责人: HSIAO-PING H MOORE
• 金额: $ 18.14万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-07-01 至 1997-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2177807
• 关键词: Golgi apparatus; guanine nucleotide binding protein; hormone regulation /control mechanism; intracellular membranes; intracellular transport; laboratory mouse; laboratory rabbit; laboratory rat; membrane activity; molecular cloning; nucleic acid sequence; peptide hormone; polymerase chain reaction; protein transport; secretion; site directed mutagenesis; vesicle /vacuole

The long term goal of this proposal is to understand the molecular machinery involved in intracellular membrane transport and secretion in neural, endocrine, and exocrine cells. Most cells have the capacity to secrete proteins, but not all cells utilize the same machinery. In particular, secretion from mammalian cells can take many different forms. The different pathways enable the cells to externalize molecules in a timely and spatially regulated fashion. These pathways together control a variety of cellular processes, including plasma membrane growth, cell-cell communication, and regulation of cell surface transport activities. Currently, little is known about the molecular components controlling export from each pathway, and how the machinery differ from one another. Neuroendocrine cells will be used as a model system to study two secretory pathways: a constitutive pathway and a regulated pathway. Exocytotic vesicles involved in these two secretory pathways are formed from the same organelle, the trans-Golgi network. Thus, our studies will be aimed at understanding the mechanisms for transport between the trans-Golgi network and the cell surface along both paths. The specific goals of these studies are: (1) to elucidate the mechanism for the formation of constitutive and regulated vesicles from the trans-Golgi network; proteins that may participate in these processes will be identified and their roles in vesicle budding will be tested in an in vitro assay that reconstitutes transport; (2) to study the components involved in vesicle targeting and fusion. GTP binding proteins and their accessory proteins involved in these processes will be identified and studied. Whether these factors are unique to the individual pathway will be determined; (3) to study the mechanism for sorting of proteins between the constitutive and the regulated pathways. Structural determinants important for sorting will be defined by mutagenesis studies. The current model for sorting will be examined by an in vivo test to determine if sorting of hormones into the regulated secretory pathway is achieved by formation of molecular aggregates.

该提议的长期目标是了解分子 涉及细胞内膜运输和分泌的机械 神经，内分泌和外分泌细胞。大多数单元具有 分泌蛋白质，但并非所有细胞都使用相同的机械。在 特别是，哺乳动物细胞的分泌可以采取许多不同的形式。 不同的途径使细胞能够在A中外部化分子 及时和空间监管的时尚。这些途径共同控制 各种细胞过程，包括质膜生长，细胞细胞 通信和调节细胞表面运输活性。 目前，对控制的分子成分知之甚少 从每个路径出口，以及机械如何相互不同。 神经内分泌细胞将用作研究两个分泌的模型系统 途径：构成途径和一个受调节的途径。胞吐 这两个分泌途径涉及的囊泡是由相同的 Organelle，Trans-Golgi网络。因此，我们的研究将针对 了解反式高尔基网络之间运输的机制 沿这两个路径的细胞表面。这些研究的具体目标 为：（1）阐明形成本构的机制和 来自反式高尔基网络的囊泡；可能的蛋白质 参与这些过程将被确定及其在 囊泡发芽将在重组的体外测定中进行测试 运输; （2）研究与囊泡靶向和 融合。 GTP结合蛋白及其辅助蛋白参与 这些过程将被识别和研究。这些因素是否是 将确定各个途径的独特之处； （3）研究 在本构和 规范的途径。对于分类重要的结构决定因素将是 由诱变研究定义。当前的分类模型将是 通过体内测试检查，以确定将激素排序是否 通过形成分子来实现调节的分泌途径 聚合。