RRC ID 28688
Author Sato K, Nakano A.
Title Reconstitution of coat protein complex II (COPII) vesicle formation from cargo-reconstituted proteoliposomes reveals the potential role of GTP hydrolysis by Sar1p in protein sorting.
Journal J Biol Chem
Abstract Secretory proteins are transported from the endoplasmic reticulum (ER) in vesicles coated with coat protein complex II (COPII). To investigate the molecular mechanism of protein sorting into COPII vesicles, we have developed an in vitro budding reaction comprising purified coat proteins and cargo reconstituted proteolipsomes. Emp47p, a type-I membrane protein, is specifically required for the transport of an integral membrane protein, Emp46p, from the ER. Recombinant Emp46/47p proteins and the ER resident protein Ufe1p were reconstituted into liposomes whose composition resembles yeast ER membranes. When the proteoliposomes were mixed with COPII proteins and GMP-PNP, Emp46/47p, but not Ufe1p, were concentrated into COPII vesicles. We also show here that reconstituted Emp47p accelerates the GTP hydrolysis by Sar1p as stimulated by its GTPase-activating protein, Sec23/24p, both of which are components of the COPII coat. Furthermore, this GTP hydrolysis decreases the error of cargo sorting. We suggest that GTP hydrolysis by Sar1p promotes exclusion of improper proteins from COPII vesicles.
Volume 279(2)
Pages 1330-5
Published 2004-1-9
DOI 10.1074/jbc.C300457200
PII S0021-9258(18)52746-0
PMID 14627716
MeSH COP-Coated Vesicles / chemistry* Electrophoresis, Polyacrylamide Gel Endoplasmic Reticulum / metabolism Escherichia coli / metabolism GTPase-Activating Proteins Guanosine Triphosphate / chemistry Guanosine Triphosphate / metabolism Hydrolysis Light Liposomes / metabolism Membrane Proteins / chemistry Membrane Proteins / metabolism Microscopy, Electron Plasmids / metabolism Proteins / chemistry Proteolipids / metabolism Qa-SNARE Proteins Recombinant Proteins / metabolism Saccharomyces cerevisiae Proteins / chemistry Saccharomyces cerevisiae Proteins / metabolism Scattering, Radiation Time Factors Tryptophan / chemistry Vesicular Transport Proteins
IF 4.238
Times Cited 37
WOS Category BIOCHEMISTRY & MOLECULAR BIOLOGY
Resource
DNA material pKSE131 (RDB08704) pKSE132 (RDB08705) pKSE133 (RDB08706) pKSE136 (RDB08707)