MEMBRANE TARGETING/FUSION DURING VESICULAR TRAFFIC

(摘自申请者的摘要)：提出的研究目标 是为了进一步了解膜的运输机制。这个 工作将集中在TAP(跨细胞相关蛋白)上 复合体，一种最近发现的融合所需的蛋白质复合体 特定的膜伙伴，但不是所有融合事件所必需的。 该复合体与跨细胞载体囊泡特异性结合。 (TCVs)，是它们与根尖质膜融合所必需的 (下午)。这些数据表明，该复合体参与了膜 表彰活动。目前已知的只有小分子GTP结合蛋白。 参与膜分类，并因此定义其他 影响这一过程的组件对于 阐明介导膜特异性的机制。 Sztul博士计划表征TAP复合体的亚单位结构 并定义不同亚基的功能。她将分析 功能性丝锥复合体的装配要求和研究 其在TCV膜上的特异性附着机制。她还会 分析复合体的形态和相关的不同功能 具有形态定义结构的结构域。的功能 复合体将在一种改进的试验中进行评估，在该试验中，靶向和 结合可以从融合的后期阶段分离出来。使用该系统， TAP复合体与其他已知影响分子的相互作用 将检查水泡流量。大多数功能分析将 利用生化和形态方法，而 对不同成分的表征将使用分子和基因 程序。

(Adapted from applicant's abstract): The goal of the research proposed is to further understanding of the mechanisms of membrane traffic. The work will concentrate on the TAP (transcytosis associated protein complex, a recently identified complex of proteins required for fusion of specific membrane partners, but not required for all fusion events. The complex is specifically associated with transcytotic carrier vesicles (TCVs) and is necessary for their fusion with the apical plasma membrane (PM). The data suggests that the complex is involved in membrane recognition events. Currently, only small GTP-binding proteins are known to participate in membrane sorting, and consequently, defining other components that influence this process is of great significance for the elucidation of the mechanisms mediating membrane specificity. Dr. Sztul plans to characterize the subunit structure of the TAP complex and to define the function of distinct subunits. She will analyze the requirements for assembly of functional TAP complex and study the mechanism of its specific attachment to the TCV membrane. She will also analyze the morphology of the complex and correlate distinct functional domains with morphologically defined structures. The function of the complex will be assessed in a modified assay in which targeting and binding can be separated from later stages of fusion. Using the system, interactions of the TAP complex with other molecules known to influence vesicular traffic will be examined. Most of the functional analyses will utilize biochemical and morphological approaches while the characterization of distinct components will use molecular and genetic procedures.