Abstract
As the first step of protein transport along the biosynthetic (secretory/exocytotic) pathway, transport from the endoplasmic reticulum (ER) to the Golgi apparatus has received much attention over the past several decades. The general structural organization underlying this transport process is becoming more defined. The major protein components participating in the budding, pre-docking, and docking/fusion events have been identified and their mechanistic aspects investigated. Conceptually, it is now clear that protein export from the ER is a selective process. Although much remains to be defined or refined, the general picture of this transport step has now emerged.