PROTEIN FOLDING IN THE ENDOPLASMIC RETICULUM

内质网中的蛋白质折叠

• 批准号: 2179302
• 负责人: ARI H HELENIUS
• 金额: $ 25.18万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1982
• 资助国家: 美国
• 起止时间: 1982-01-01 至 1995-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2179302
• 关键词: G protein; HeLa cells; Vesiculovirus; calcium flux; conformation; disulfide bond; electron microscopy; endoplasmic reticulum; genetic translation; glycoproteins; high performance liquid chromatography; human tissue; immunocytochemistry; immunoprecipitation; laboratory mouse; laboratory rabbit; membrane proteins; microorganism hemagglutinin; molecular chaperones; monoclonal antibody; nuclear matrix; posttranslational modifications; protein degradation; protein folding; protein sequence; protein signal sequence; radiotracer; stress proteins; tissue /cell culture; virus protein

While protein folding has been extensively studied in vitro, little is known about the process in living cells. Our goal is to elucidate how glycoproteins fold within the lumen of the endoplasmic reticulum(ER), and how the outcome of the folding process determines their fate within the cell. Secretory proteins, membrane glycoproteins and vacuolar proteins, which fold in this compartment, encounter in the ER an environment which is different in many ways from any folding compartment in the cell where protein folding takes place. As model proteins, we will rely mainly on two well-characterized viral membrane glycoproteins; influenza hemagglutinin (HA) and vesicular stomatitis virus (VSV) G protein. Our main objectives are to determine to which extent the kinetics and efficiency of co- and post-translational folding depend on stress proteins, folding factors, chaperonins, signal sequence cleavage, N-linked glycosylation, redox potential, translation rate, calcium concentration and temperature. Since a large part of the folding is co-translational, we will determine whether the translation rate and ribosome pausing regulate the process. We will isolate and characterize new ER factors responsible for folding, misfolding and retention of proteins in the ER and in associated organelles. We will investigate the molecular signals that prevent misfolded proteins from exiting to the Golgi complex, and induce their degradation. The organelle where degradation occurs will be analyzed and isolated. To better understand the structure of the ER, we will finally study the composition and function of the matrix of insoluble proteins in the ER membrane and lumen. This matrix is likely to be involved in the quality control processes of the ER. By focussing on the cell biological aspects of the co- and post translational folding i living cells, we hope to learn more about the fundamental aspect of secretion, organelle biogenesis and post- translational regulation. Hopefully, the results will also throw some light on a number of pathological states which can be categorized as "ER storage diseases".

虽然蛋白质折叠在体外进行了广泛研究，但几乎没有 知道活细胞的过程。 我们的目标是阐明如何 糖蛋白在内质网（ER）的腔内折叠，并且 折叠过程的结果如何确定其命运 细胞。 分泌蛋白，膜糖蛋白和液泡蛋白， 在此隔间中哪个折叠，在ER中遇到一个环境 在许多方面不同于单元格中的任何折叠室 蛋白质折叠发生。 作为模型蛋白，我们将主要依靠两个 特征良好的病毒膜糖蛋白；流感血凝素 （HA）和囊泡气孔病毒（VSV）G蛋白。 我们的主要目标是确定动力学和 共同和后翻译后的效率取决于压力 蛋白质，折叠因子，伴侣蛋白，信号序列裂解，N连接 糖基化，氧化还原电位，翻译率，钙浓度和 温度。 由于折叠的很大一部分是共同的，我们 将确定翻译率和核糖体暂停调节是否 过程。 我们将隔离并表征负责的新ER因素 用于折叠，错误折叠和保留蛋白质中的蛋白质 相关细胞器。 我们将研究分子信号 防止错误折叠的蛋白质退出到高尔基体配合物，并诱导 他们的退化。 将分析发生降解的细胞器 并孤立。 为了更好地了解急诊室的结构，我们将 最后研究不溶性矩阵的组成和功能 ER膜和管腔中的蛋白质。 这个矩阵可能是 参与ER的质量控制过程。 通过重点关注共同的细胞生物学方面 翻译折叠I活细胞，我们希望了解更多有关 分泌的基本方面，细胞器生物发生和后 翻译法规。 希望结果也会抛出一些 可以将许多可以归类为“ ER的病理状态 存储疾病”。