STRUCTURE OF THE EXOCYTOTIC FUSION PORE IN MAST CELLS

肥大细胞胞吐融合孔的结构

• 批准号: 2184179
• 负责人: Julio M Fernandez
• 金额: $ 23.03万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-02-01 至 1996-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2184179
• 关键词: anesthetics; biological signal transduction; calcium; cell membrane; cellular polarity; chemical structure function; conformation; electrical conductance; endocytosis; exocytosis; fatty acids; fluidity; fluorescence microscopy; fluorescent dye /probe; gene mutation; guanine nucleotide binding protein; guanine nucleotides; laboratory mouse; mast cell; membrane fusion; membrane lipids; membrane permeability; membrane potentials; membrane structure; pigments; pore forming protein; single cell analysis; temperature; time resolved data; vesicle /vacuole; voltage /patch clamp

The long-term goal of this proposal is to elucidate the molecular structure of the exocytotic fusion pore, the water-filled connection that forms between the lumen of a secretory granule and the extracellular space, upon exocytosis. Understanding the structure and regulation of the exocytotic fusion pore is one of the most outstanding questions on the mechanisms of exocytotic secretion. Towards this aim we will measure the time course of the conductance of single fusion pores. Pore conductance will be measured from the changes in the admittance of single patch-clamped mast cells caused by the formation of individual fusion pores as the cell undergoes exocytosis. We will study exocytotic fusion pores that form transiently and fusion pores that, after formation, expand irreversibly, completing exocytosis. We will also study the pores that form in the final stages of membrane retrieval events. We will classify and characterize the stages of development and the properties of the three types of pores. We will attempt to perturb each stage gain knowledge about the participating molecular structures. We will perturb pore structure by changing the physical properties of the mast cell membrane through changes in temperature, addition of anesthetics or fatty acid supplements; by chemical regulators like GTPgammaS and Ca++; and by genetic mutations like those of the pigment mutant Ruby. The result of these manipulations will be the basis for proposing models of the structure of the fusion pore as it evolves to complete the exocytotic event.

该提议的长期目标是阐明分子结构 胞吐融合孔的形成的水连接 在分泌颗粒的管腔和细胞外空间之间 胞吞作用。 了解胞吐的结构和调节 融合孔是关于机制的最杰出问题之一 胞吐分泌。 为了实现这一目标，我们将衡量的时间过程 单融合孔的电导。 孔电导将测量 从单个斑块夹桅杆细胞的入学的变化中 由单个融合孔的形成引起 胞吞作用。 我们将研究瞬时形成的胞吐融合孔 融合孔，在编队后，不可逆地扩展，完成 胞吞作用。 我们还将研究在最后阶段的毛孔 膜检索事件。 我们将分类并表征 开发和三种孔的特性。 我们将 试图扰动每个阶段获得有关参与的知识 分子结构。 我们将通过更改孔结构 肥大细胞膜的物理特性通过变化 温度，加入麻醉或脂肪酸补充剂；通过化学 诸如GTPGAMMAS和CA ++等调节剂；以及像遗传突变一样 颜料突变的红宝石。 这些操纵的结果将是 提出融合孔结构模型的基础 进化以完成胞吐事件。