Polypeptide‐binding proteins mediate completion of co‐translational protein translocation into the mammalian endoplasmic reticulum
Open Access
- 18 April 2003
- journal article
- Published by Springer Nature in EMBO Reports
- Vol. 4 (5) , 505-510
- https://doi.org/10.1038/sj.embor.embor826
Abstract
The first step in the secretion of most mammalian proteins is their transport into the lumen of the endoplasmic reticulum (ER). Transport of pre‐secretory proteins into the mammalian ER requires signal peptides in the precursor proteins and a protein translocase in the ER membrane. In addition, hitherto unidentified lumenal ER proteins have been shown to be required for vectorial protein translocation. This requirement was confirmed in this study by using proteoliposomes that were made from microsomal detergent extracts and contained either low or high concentrations of lumenal ER proteins. Furthermore, immunoglobulin‐heavy‐chain‐binding protein (BiP) was shown to be able to substitute for the full set of lumenal proteins and, in the case of biotinylated precursor proteins, avidin was found to be able to substitute for lumenal proteins. Thus, the polypeptide‐chain‐binding protein BiP was identified as one lumenal protein that is involved in efficient vectorial protein translocation into the mammalian ER.Keywords
This publication has 30 references indexed in Scilit:
- Sec63p and Kar2p are required for the translocation of SRP-dependent precursors into the yeast endoplasmic reticulum in vivoThe EMBO Journal, 2001
- Protein Disulphide Isomerase and a Lumenal Cyclophilin‐Type Peptidyl Prolyl Cis‐Trans Isomerase are in Transient Contact with Secretory Proteins During Late Stages of TranslocationEuropean Journal of Biochemistry, 1995
- Protein Disulphide Isomerase and a Lumenal Cyclophilin-Type Peptidyl Prolyl Cis-Trans Isomerase are in Transient Contact with Secretory Proteins During Late Stages of TranslocationEuropean Journal of Biochemistry, 1995
- Protein translocation into proteoliposomes reconstituted from purified components of the endoplasmic reticulum membraneCell, 1993
- Association of folding intermediates of glycoproteins with calnexin during protein maturationNature, 1993
- Lumenal proteins of the mammalian endoplasmic reticulum are required to complete protein translocationCell, 1993
- Bidirectional movement of a nascent polypeptide across microsomal membranes reveals requirements for vectorial translocation of proteinsCell, 1992
- Assembly of translocation-competent proteoliposomes from detergent-solubilized rough microsomesCell, 1990
- Immunoglobulin heavy chain binding proteinNature, 1983
- Transfer of proteins across membranes. I. Presence of proteolytically processed and unprocessed nascent immunoglobulin light chains on membrane-bound ribosomes of murine myeloma.The Journal of cell biology, 1975