Rapid redistribution of Golgi proteins into the ER in cells treated with brefeldin A: evidence for membrane cycling from Golgi to ER

J Lippincott-Schwartz, LC Yuan, JS Bonifacino… - Cell, 1989 - cell.com
J Lippincott-Schwartz, LC Yuan, JS Bonifacino, RD Klausner
Cell, 1989cell.com
In cells treated with brefeldin A (BFA), movement of newly synthesized membrane proteins
from the endoplasmic reticulum (ER) to the Golgi apparatus was blocked. Surprisingly, the
glycoproteins retained in the ER were rapidly processed by cislmedial Golgi enzymes but
not by frans Golgi enzymes. An explanation for these observations was provided from
morphological studies at both the light and electron microscopic levels using markers for the
cislmedial and trans Golgi. They revealed a rapid and dramatic redistribution to the ER of …
Summary
In cells treated with brefeldin A (BFA), movement of newly synthesized membrane proteins from the endoplasmic reticulum (ER) to the Golgi apparatus was blocked. Surprisingly, the glycoproteins retained in the ER were rapidly processed by cislmedial Golgi enzymes but not by frans Golgi enzymes. An explanation for these observations was provided from morphological studies at both the light and electron microscopic levels using markers for the cislmedial and trans Golgi. They revealed a rapid and dramatic redistribution to the ER of components of the cislmedial but not the tram Golgi in response to treatment with BFA. Upon removal of BFA, the morphology of the Golgi apparatus was rapidly reestablished and proteins normally transported out of the ER were efficiently and rapidly sorted to their final destinations. These results suggest that BFA disrupts a dynamic membranerecycling pathway between the ER and &/medial Golgi, effectively blocking membrane transport out of but not back to the ER.
cell.com