Oligomerization of a Cargo Receptor Directs Protein Sorting into COPII-coated Transport Vesicles
AUTOR(ES)
Sato, Ken
FONTE
The American Society for Cell Biology
RESUMO
Secretory proteins are transported from the endoplasmic reticulum (ER) to the Golgi complex in vesicles coated with coat protein complex II (COPII). The incorporation of certain transport molecules (cargo) into the COPII vesicles is thought to be mediated by cargo receptors. Here we show that Emp47p, a type-I membrane protein, is specifically required for the transport of an integral membrane protein, Emp46p, from the ER. Exit of Emp46p from the ER was saturable and dependent on the expression level of Emp47p. Emp46p binding to Emp47p occurs in the ER through the coiled-coil region in the luminal domains of both Emp47p and Emp46p, and dissociation occurs in the Golgi. Further, this coiled-coil region is also required for Emp47p to form an oligomeric complex of itself in the ER, which is essential for exit of Emp47p from the ER. Our results suggest that Emp47p is a receptor protein for Emp46p that allows for the selective transport of this protein, and this event involves receptor oligomerization.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=165697Documentos Relacionados
- Erv14p Directs a Transmembrane Secretory Protein into COPII-coated Transport Vesicles
- Surface structure of the COPII-coated vesicle
- Okadaic Acid Induces Selective Arrest of Protein Transport in the Rough Endoplasmic Reticulum and Prevents Export into COPII-Coated Structures
- The absence of Emp24p, a component of ER-derived COPII-coated vesicles, causes a defect in transport of selected proteins to the Golgi.
- Selective packaging of cargo molecules into endoplasmic reticulum-derived COPII vesicles