PROTEIN FOLDING IN THE ENDOPLASMIC RETICULUM

虽然蛋白质折叠在体外已经得到了广泛的研究，但很少有人研究 知道活细胞中的这一过程。我们的目标是阐明 糖蛋白在内质网(ER)的管腔内折叠，并且 折叠过程的结果如何决定它们在 手机。分泌蛋白、膜糖蛋白和空泡蛋白， 在这个隔间里折叠，在急诊室遇到一个环境，这是 在许多方面不同于细胞中的任何折叠隔间 蛋白质折叠就会发生。作为模型蛋白质，我们将主要依靠两种 特性良好的病毒膜糖蛋白；流感血凝素 (HA)和水疱性口炎病毒(VSV)G蛋白。 我们的主要目标是确定在何种程度上的动力学和 共平移和平移后折叠的效率取决于应力 蛋白质，折叠因子，伴侣蛋白，信号序列切割，N-连接 糖基化、氧化还原电位、转化率、钙浓度和 温度。由于折叠的很大一部分是共翻译的，我们 将决定翻译速率和核糖体停顿是否调节 这一过程。我们将分离和鉴定新的ER因素 用于蛋白质在内质网和内质网中的折叠、错误折叠和保留 伴生细胞器。我们将研究分子信号 防止错误折叠的蛋白质进入高尔基复合体，并诱导 他们的堕落。将对发生退化的细胞器进行分析 而且与世隔绝。为了更好地了解ER的结构，我们将 最后研究了不溶物基质的组成和功能 内质网膜和管腔中的蛋白质。这个矩阵很可能是 参与急诊室的质量控制流程。 通过重点研究联合和POST的细胞生物学方面 翻译折叠i活细胞，我们希望了解更多关于 分泌物的基本方面，细胞器的生物发生和后 翻译法规。希望结果也能抛出一些 可归类为“内质网”的若干病理状态 储藏病“。

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".