COPII-cargo interactions direct protein sorting into ER-derived transport vesicles.

Journal Article

Vesicles coated with coat protein complex II (COPII) selectively transport molecules (cargo) and vesicle fusion proteins from the endoplasmic reticulum (ER) to the Golgi complex. We have investigated the role of coat proteins in cargo selection and recruitment. We isolated integral membrane and soluble cargo proteins destined for transport from the ER in complexes formed in the presence of Sar1 and Sec23/24, a subset of the COPII components, and GTP or GMP-PNP. Vesicle fusion proteins of the vSNARE family and Emp24, a member of a putative cargo carrier family, were also found in COPII complexes. The inclusion of amino-acid permease molecules into the complex depended on the presence of Shr3, a protein required for the permease to leave the ER. Resident ER proteins Sec61, BiP (Kar2) and Shr3 were not included in the complexes, indicating that the COPII components bound specifically to vesicle cargo. COPII-cargo complexes and putative cargo adaptor-cargo complexes were also isolated from COPII vesicles. Our results indicate that cargo packaging signals and soluble cargo adaptors are recognized by a recruitment complex comprising Sar1-GTP and Sec23/24.

Full Text

Duke Authors

Cited Authors

  • Kuehn, MJ; Herrmann, JM; Schekman, R

Published Date

  • January 8, 1998

Published In

Volume / Issue

  • 391 / 6663

Start / End Page

  • 187 - 190

PubMed ID

  • 9428766

International Standard Serial Number (ISSN)

  • 0028-0836

Digital Object Identifier (DOI)

  • 10.1038/34438

Language

  • eng

Conference Location

  • England