Coatomer interaction with di-lysine endoplasmic reticulum retention motifs
1Basel Institute for Immunology, Switzerland.
Abstract:
Although signals for retention in the endoplasmic reticulum (ER) have been identified in the cytoplasmic domain of various ER-resident type I transmembrane proteins, the mechanisms responsible for ER retention are still unknown. Yeast and mammalian ER retention motifs interacted specifically in cell lysates with the coatomer, a polypeptide complex implicated in membrane traffic. Mutations that affect the ER retention capacity of the motifs also abolished binding of the coatomer. These results suggest a role for the coatomer in the retrieval of transmembrane proteins to the ER in both yeast and mammals.
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