Format

Send to

Choose Destination
See comment in PubMed Commons below
Cell. 2006 Aug 25;126(4):727-39.

Cotranslocational degradation protects the stressed endoplasmic reticulum from protein overload.

Author information

1
Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY 10016, USA.

Erratum in

  • Cell. 2006 Dec 16;127(6):1284.

Abstract

The ER's capacity to process proteins is limited, and stress caused by accumulation of unfolded and misfolded proteins (ER stress) contributes to human disease. ER stress elicits the unfolded protein response (UPR), whose components attenuate protein synthesis, increase folding capacity, and enhance misfolded protein degradation. Here, we report that P58(IPK)/DNAJC3, a UPR-responsive gene previously implicated in translational control, encodes a cytosolic cochaperone that associates with the ER protein translocation channel Sec61. P58(IPK) recruits HSP70 chaperones to the cytosolic face of Sec61 and can be crosslinked to proteins entering the ER that are delayed at the translocon. Proteasome-mediated cytosolic degradation of translocating proteins delayed at Sec61 is cochaperone dependent. In P58(IPK-/-) mice, cells with a high secretory burden are markedly compromised in their ability to cope with ER stress. Thus, P58(IPK) is a key mediator of cotranslocational ER protein degradation, and this process likely contributes to ER homeostasis in stressed cells.

PMID:
16923392
DOI:
10.1016/j.cell.2006.06.051
[Indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center