ER proteins of widely differing abundance are retrieved from the Golgi by KDEL-receptor. Abundant tend to have KDEL rather than HDEL signals, whereas ADEL and DDEL not used in most organisms. Here, we explore mechanism selective retrieval signal capture KDEL-receptor how binds with 10-fold higher affinity KDEL. Our results show carboxyl-terminus moves along a ladder arginine residues as it ente...

Interleukin-24 (IL-24) is a cytokine belonging to the IL-10 gene family. This cytokine selectively induces apoptosis in cancer cells, without harming normal cells, through a mechanism involving endoplasmic reticulum (ER) stress response. TAT-IL-24-KDEL is a fusion protein that efficiently enters the tumor cells and locates in the ER. Here we report that TAT-IL-24-KDEL induced apoptosis in human...

To investigate the role of the KDEL receptor in the retrieval of protein toxins to the mammalian cell endoplasmic reticulum (ER), lysozyme variants containing AARL or KDEL C-terminal tags, or the human KDEL receptor, have been expressed in toxin-treated COS 7 and HeLa cells. Expression of the lysozyme variants and the KDEL receptor was confirmed by immunofluorescence. When such cells were chall...

Membrane trafficking via the Golgi-localised KDEL receptor activates signalling cascades that coordinate both trafficking and other cellular functions, including autophagy and extracellular matrix degradation. In this study, we provide evidence that membrane trafficking activates KDEL receptor and the Src family kinases at focal adhesions of HeLa cells, where this phosphorylates ADP-ribosylatio...

AC-terminal KDEL-like motif prevents secretion of soluble endoplasmic reticulum (ER)-resident proteins. This motif interacts with KDEL receptors localized in the intermediate compartment and Golgi apparatus. Such binding triggers retrieval back to the ER via a coat protein I-dependent pathway. To date, two human KDEL receptors have been reported. Here, we report the Golgi localization of a thir...

The tetrapeptide KDEL is commonly found at the C terminus of soluble proteins of the endoplasmic reticulum (ER), and it contributes to their localization by interacting with a receptor that recycles between the Golgi complex and the ER. We investigated the effects of the addition of KDEL to phaseolin, a protein normally delivered from the ER to storage vacuoles via the Golgi complex. We show th...

Most endoplasmic reticulum (ER)-retained proteins contain a carboxy-terminal signal sequence called the ER retention signal motif such as the Lys-Asp-Glu-Leu (KDEL) motif. Using this molecular mechanism, we developed a new dominant-negative assay, designated the KDEL-tag trap assay, to negatively regulate secretion of disulfide bond-dependent protein dimers, as typified by TGF-beta superfamily ...

The KDEL receptor is a Golgi/intermediate compartment-located integral membrane protein that carries out the retrieval of escaped ER proteins bearing a C-terminal KDEL sequence. This occurs throughout retrograde traffic mediated by COPI-coated transport carriers. The role of the C-terminal cytoplasmic domain of the KDEL receptor in this process has been investigated. Deletion of this domain did...