PROTEIN TRANSLOCATION AND PROCESSING IN OVIDUCT

这是一项对母鸡输卵管信号肽进行研究的建议。 去除氨基端信号肽的膜结合蛋白水解酶 新生的分泌前体蛋白。该酶将被提纯并 以生化为特征的。这种蛋白水解酶代表一个数字 参与各种细胞加工的高度特异的酶 激素前体和发酵原的激活，切除 来自多功能前体的生物活性多肽及其转运 细胞质合成的蛋白质进入线粒体 叶绿体。一种改进的信号肽酶活性测定方法将是 这将有助于它的隔离和定性。特定的 将开发该酶的抑制剂来表征其作用机制 类，并探讨其在传输过程中的作用。母鸡输卵管信号 识别粒子，一种识别蛋白质和RNA的复合体 核糖体合成分泌蛋白并使它们附着于 内质网上的运输部位，将被识别，分离， 并用于研究卵清蛋白在其同系物中的分泌机制 组织。一种抗人胎盘前期信号肽的抗体 催乳素将被制备并用于探索信号的作用 蛋白质转运过程中的多肽。这项研究的长期目标 就是分离分泌蛋白质运输所需的成分 进入内质网，并将其重组为人工 脂质体以功能性的方式。这样一个重组的系统将导致 对细胞合成和合成的机制的详细了解 运输分泌蛋白质。

This is a proposal to undertake a study of hen oviduct signal peptidase, a membrane-bound proteinase that removes amino-terminal signal peptides from nascent secretory precursor proteins. The enzyme will be purified and characterized biochemically. This proteinase is representative of a number of highly-specific enzymes involved in a variety of cellular processing events such as activation of hormone precursors and zymogens, excision of biologically-active peptides from multifunctional precursors, and transport of cytoplasmically-synthesized proteins into mitochondria and chloroplasts. An improved assay for signal peptidase activity will be developed that will aid its isolation and characterization. Specific inhibitors of the enzyme will be developed to characterize its mechanistic class and to probe its role in the transport process. Hen oviduct signal recognition particle, a complex of protein and RNA that recognizes ribosomes synthesizing secretory proteins and causes them to attach to transport sites on the endoplasmic reticulum, will be identified, isolated, and used to study the mechanism of secretion of ovalbumin in its homologous tissue. An antibody specific for the signal peptide of human pre-placental lactogen will be prepared and used to explore the role of the signal peptide in the protein transport process. A long-term goal of this study is to separate the components required for transport of secretory proteins into the endoplasmic reticulum and reconstitute them into artificial liposomes in a functional manner. Such a reconstituted system will lead to a detailed understanding of the mechanism by which cells synthesize and transport secretory proteins.