Swanton Eileithyia, Bulleid Neil J
School of Biological Sciences, University of Manchester, UK.
Mol Membr Biol. 2003 Apr-Jun;20(2):99-104. doi: 10.1080/0968768031000069241.
Proteins destined for secretion are translocated across or inserted into the endoplasmic reticulum membrane whereupon they fold and assemble to their native state before their subsequent transport to the Golgi apparatus. Proteins that fail to fold correctly are translocated back across the endoplasmic reticulum membrane to the cytosol where they become substrates for the cytosolic degradative machinery. Central to translocation is a protein pore in the membrane called the translocon that allows passage of proteins in and out of the endoplasmic reticulum. It is clear that the conformation of the polypeptide chain influences the translocation process and that there is a temporal relationship between modification of the chain, translocation and folding. This review will consider when and how the polypeptide chain folds, and how this might influence translocation into and out of the ER; and discuss how protein folding might affect post-translational modification of the polypeptide chain following translocation into the ER lumen.
destined for secretion are translocated across or inserted into the endoplasmic reticulum membrane whereupon they fold and assemble to their native state before their subsequent transport to the Golgi apparatus. Proteins that fail to fold correctly are translocated back across the endoplasmic reticulum membrane to the cytosol where they become substrates for the cytosolic degradative machinery. Central to translocation is a protein pore in the membrane called the translocon that allows passage of proteins in and out of the endoplasmic reticulum. It is clear that the conformation of the polypeptide chain influences the translocation process and that there is a temporal relationship between modification of the chain, translocation and folding. This review will consider when and how the polypeptide chain folds, and how this might influence translocation into and out of the ER; and discuss how protein folding might affect post-translational modification of the polypeptide chain following translocation into the ER lumen.
分泌型蛋白质穿过或插入内质网膜,然后折叠并组装成天然状态,随后被转运到高尔基体。未能正确折叠的蛋白质会被重新转运回内质网膜进入细胞质溶胶,在那里它们成为细胞质降解机制的底物。转运的核心是膜上一个名为转位子的蛋白质孔道,它允许蛋白质进出内质网。很明显,多肽链的构象会影响转运过程,并且链的修饰、转运和折叠之间存在时间关系。本综述将探讨多肽链何时以及如何折叠,以及这可能如何影响进出内质网的转运;并讨论蛋白质折叠如何影响多肽链转运到内质网腔后其翻译后修饰。