Identification of an intermediate compartment involved in protein transport from endoplasmic reticulum to Golgi apparatus.
We have studied the role of a previously described tubulovesicular compartment near the cis-Golgi apparatus in endoplasmic reticulum (ER)-to-Golgi protein transport by light and immunoelectron microscopy in Vero cells. The compartment is defined by a 53-kDa transmembrane protein designated p53. When transport of the vesicular stomatitis virus strain ts045 G protein was arrested at 39.5 degrees C, the G protein accumulated in the ER but had access to the p53 compartment. At 15 degrees C, the G protein was exported from the ER into the p53 compartment which formed a compact structure composed of vesicular and tubular profiles in close proximity to the Golgi. Upon raising the temperature to 32 degrees C, the G protein migrated through the Golgi apparatus while the p53 compartment resumed its normal structure again. These results establish the p53 compartment as the 15 degrees C intermediate of the ER-to-Golgi protein transport pathway.
Schweizer
A
A
Department of Pharmacology, University of Basel, Switzerland.
Fransen
J A
JA
Matter
K
K
Kreis
T E
TE
Ginsel
L
L
Hauri
H P
HP
D000818:Animals; D001692:Biological Transport; D004721:Endoplasmic Reticulum / Q000378:metabolism* / Q000648:ultrastructure; D005455:Fluorescent Antibody Technique; D006023:Glycoproteins / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism* / Q000648:ultrastructure; D008562:Membrane Glycoproteins; D008565:Membrane Proteins / Q000378:metabolism; D016253:Microscopy, Immunoelectron; D008954:Models, Biological; D015388:Organelles / Q000378:metabolism / Q000648:ultrastructure; D013696:Temperature; D014709:Vero Cells; D014721:Vesicular stomatitis Indiana virus / Q000378:metabolism*; D014759:Viral Envelope Proteins / Q000378:metabolism*
C028391:G protein, vesicular stomatitis virus; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D014759:Viral Envelope Proteins