期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1998
卷号：95
期号：20
页码：11649-11654
DOI：10.1073/pnas.95.20.11649
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Coatomer, the major component of the coat of COPI transport vesicles, binds both to the dilysine motif of resident membrane proteins of the endoplasmic reticulum and to the cytoplasmic domain of p23, a major type I membrane protein of COPI vesicles. Using a photocrosslinking approach, we find that under native conditions a peptide analogous to the cytoplasmic domain of p23 interacts with coatomer exclusively through its {gamma} subunit and shares its binding site with a KKXX retrieval motif. However, upon dissociation of coatomer, interaction with various subunits, including an -, {beta}'-, {varepsilon}-COP subcomplex, of the photoreactive peptide is observed. We suggest that, under physiological conditions, interaction of coatomer with both endoplasmic reticulum retrieval motifs and the cytoplasmic domain of p23 is mediated by {gamma}-COP.
