Retention In Endoplasmic Reticulum 1 (RER1)

RER1 is a multi-pass membrane protein that is localized to the golgi apparatus. It is involved in the retention of endoplasmic reticulum (ER) membrane proteins in the ER and retrieval of ER membrane proteins from the early Golgi compartment to facilitate gamma-secretase complex assembly. Human Rer1 protein was expressed in HeLa cells and the subcellular distribution analyzed by double immunofluorescence and immunoelectron microscopy of thawed cryosections. The tagged protein was localized to the Golgi apparatus and peripheral elements of the ER-Golgi interface. High overexpression leads to relocation of human Rer1 to ER-like structures together with KDEL-receptor and affects the structural organization of the Golgi apparatus. Under conditions of brefeldin A treatment, human Rer1 distributes together with recycling Golgi proteins.