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.

这项提案的长期目标是了解分子 参与细胞内膜运输和分泌的机制， 神经、内分泌和外分泌细胞。大多数细胞都有能力 分泌蛋白质，但并非所有细胞都使用相同的机制。在 特别地，来自哺乳动物细胞的分泌物可以采取许多不同的形式。 不同的途径使细胞能够将分子外化， 时间和空间的调节方式。这些通路共同控制着 多种细胞过程，包括质膜生长、细胞-细胞 通信和调节细胞表面转运活动。 目前，人们对控制这些蛋白质的分子组成知之甚少， 每个人都有自己的特点，每个人都有自己的特点，每个人都有自己的特点。 神经内分泌细胞将被用作研究两种分泌的模型系统。 途径：组成性途径和调节性途径。胞吐 参与这两种分泌途径的囊泡由相同的 细胞器，高尔基体网络。因此，我们的研究将针对 了解高尔基体网络之间的运输机制 并且细胞表面沿着两条路径沿着移动。这些研究的具体目标 主要有：（1）阐明了组成型和 来自trans-Golgi网络的受调节的囊泡;可能 将确定参与这些进程的人员， 将在体外试验中测试囊泡出芽， 运输;（2）研究参与囊泡靶向的组分， 核聚变GTP结合蛋白及其辅助蛋白 将确定和研究这些进程。这些因素是否 将确定个体途径的独特性;（3）研究 在组成型和非组成型之间分选蛋白质的机制 调控途径。对排序很重要的结构决定因素是 通过诱变研究确定。目前的排序模型将是 通过体内试验检查，以确定是否将激素分选到 调节分泌途径是通过形成分子 集料.