Abstract |
The protein-disulfide isomerase (PDI) family member anterior gradient 2 (AGR2) is reportedly overexpressed in numerous cancers and plays a role in cancer development. However, to date the molecular functions of AGR2 remain to be characterized. Herein we have identified AGR2 as bound to newly synthesized cargo proteins using a proteomics analysis of endoplasmic reticulum (ER) membrane-bound ribosomes. Nascent protein chains that translocate into the ER associate with specific ER luminal proteins, which in turn ensures proper folding and posttranslational modifications. Using both imaging and biochemical approaches, we confirmed that AGR2 localizes to the lumen of the ER and indirectly associates with ER membrane-bound ribosomes through nascent protein chains. We showed that AGR2 expression is controlled by the unfolded protein response and is in turn is involved in the maintenance of ER homeostasis. Remarkably, we have demonstrated that siRNA-mediated knockdown of AGR2 significantly alters the expression of components of the ER-associated degradation machinery and reduces the ability of cells to cope with acute ER stress, properties that might be relevant to the role of AGR2 in cancer development.
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Authors | Arisa Higa, Audrey Mulot, Frédéric Delom, Marion Bouchecareilh, Duc Thang Nguyên, Daniel Boismenu, Michael J Wise, Eric Chevet |
Journal | The Journal of biological chemistry
(J Biol Chem)
Vol. 286
Issue 52
Pg. 44855-68
(Dec 30 2011)
ISSN: 1083-351X [Electronic] United States |
PMID | 22025610
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- AGR2 protein, human
- Mucoproteins
- Oncogene Proteins
- Proteins
- Proto-Oncogene Proteins
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Topics |
- Animals
- COS Cells
- Chlorocebus aethiops
- Dogs
- Endoplasmic Reticulum
(enzymology, genetics)
- Endoplasmic Reticulum Stress
(physiology)
- Gene Expression Regulation
(physiology)
- HEK293 Cells
- Homeostasis
(physiology)
- Humans
- Mice
- Mucoproteins
- Oncogene Proteins
- Proteins
(genetics, metabolism)
- Proto-Oncogene Proteins
(genetics, metabolism)
- Unfolded Protein Response
(physiology)
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