A C-terminal signal prevents secretion of luminal ER proteins

doi:10.1016/0092-8674(87)90086-9

Cell

Volume 48, Issue 5, 13 March 1987, Pages 899-907

https://doi.org/10.1016/0092-8674(87)90086-9 Get rights and content

Abstract

Proteins that permanently reside in the lumen of the endoplasmic reticulum (ER) must somehow be distinguished from newly synthesized secretory proteins, which pass through this compartment on their way out of the cell. Three luminal ER proteins whose sequence is known, grp78 (“BiP”), grp94, and protein disulphide isomerase, share the carboxy-terminal sequence Lys-Asp-Glu-Leu (KDEL). We show that deletion (or extension) of the carboxyl terminus of grp78 results in secretion of this protein when it is expressed in COS cells. Conversely, a derivative of chicken lysozyme containing the last six amino acids of grp78 fails to be secreted and instead accumulates in the ER. We propose that the KDEL sequence marks proteins that are to be retained in the ER and discuss possible retention mechanisms.

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Cell

ArticleA C-terminal signal prevents secretion of luminal ER proteins

Abstract

J. Mol. Biol.

Trends Biochem. Sci.

Cell

Meth. Enzymol.

Cell

J. Mol. Biol.

J. Biol. Chem.

J. Biol. Chem.

J. Mol. Biol.

J. Biol. Chem.

Cell

Cell

Cell

J. Biol. Chem.

Posttranslational association of immunoglobulin heavy chain binding protein with nascent heavy chains in nonsecreting and secreting hybridomas

J. Cell Biol.

Sequence of protein disulphide isomerase and implications of its relationship to thioredoxin

Nature

Isolation of monoclonal-antibodies specific for human c-myc protooncogene product

Mol. Cell. Biol.

Article
A C-terminal signal prevents secretion of luminal ER proteins