Freeze Hudson H, Kranz Christian
Burnham Institute for Medical Research, La Jolla, California.
Curr Protoc Immunol. 2008 Nov;Chapter 8:8.15.1-8.15.26. doi: 10.1002/0471142735.im0815s83.
Nearly all proteins entering the lumen of the endoplasmic reticulum (ER) become glycosylated en route to a cellular organelle, the plasma membrane, or the extracellular space. Many glycans can be attached to proteins, but the most common are the N-linked glycans (oligosaccharides). These chains are added very soon after a protein enters the ER, but they undergo extensive remodeling (processing), especially in the Golgi. Processing changes the sensitivity of the N-glycan to enzymes that cleave entire sugar chains or individual monosaccharides, which also changes the migration of the protein on SDS gels. These changes can be used to indicate when a protein has passed a particular subcellular location. This unit details some of the methods used to track a protein as it traffics from the ER to the Golgi toward its final location.
几乎所有进入内质网（ER）腔的蛋白质在前往细胞器、质膜或细胞外空间的途中都会发生糖基化。许多聚糖可以附着在蛋白质上，但最常见的是N-连接聚糖（寡糖）。这些糖链在蛋白质进入内质网后很快就会添加，但它们会经历广泛的重塑（加工），尤其是在高尔基体中。加工改变了N-聚糖对切割整个糖链或单个单糖的酶的敏感性，这也改变了蛋白质在SDS凝胶上的迁移。这些变化可用于指示蛋白质何时通过特定的亚细胞位置。本单元详细介绍了一些用于追踪蛋白质从内质网运输到高尔基体并最终到达其最终位置的方法。
