scholarly journals The unfolded protein response regulator GRP78/BiP is required for endoplasmic reticulum integrity and stress-induced autophagy in mammalian cells

2008 ◽  
Vol 15 (9) ◽  
pp. 1460-1471 ◽  
Author(s):  
J Li ◽  
M Ni ◽  
B Lee ◽  
E Barron ◽  
D R Hinton ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Unfolded Protein Response ◽  
Mammalian Cells ◽  
Response Regulator ◽  
Unfolded Protein ◽  
The Unfolded Protein Response ◽  
Protein Response

scholarly journals Intrinsic Capacities of Molecular Sensors of the Unfolded Protein Response to Sense Alternate Forms of Endoplasmic Reticulum Stress

2006 ◽  
Vol 17 (7) ◽  
pp. 3095-3107 ◽  
Author(s):  
Jenny B. DuRose ◽  
Arvin B. Tam ◽  
Maho Niwa
Keyword(s):  
Endoplasmic Reticulum ◽  
Er Stress ◽  
Unfolded Protein Response ◽  
Mammalian Cells ◽  
Atpase Inhibitor ◽  
Molecular Sensors ◽  
Unfolded Protein ◽  
Alternate Forms ◽  
The Unfolded Protein Response ◽  
Protein Response

The unfolded protein response (UPR) regulates the protein-folding capacity of the endoplasmic reticulum (ER) according to cellular demand. In mammalian cells, three ER transmembrane components, IRE1, PERK, and ATF6, initiate distinct UPR signaling branches. We show that these UPR components display distinct sensitivities toward different forms of ER stress. ER stress induced by ER Ca2+ release in particular revealed fundamental differences in the properties of UPR signaling branches. Compared with the rapid response of both IRE1 and PERK to ER stress induced by thapsigargin, an ER Ca2+ ATPase inhibitor, the response of ATF6 was markedly delayed. These studies are the first side-by-side comparisons of UPR signaling branch activation and reveal intrinsic features of UPR stress sensor activation in response to alternate forms of ER stress. As such, they provide initial groundwork toward understanding how ER stress sensors can confer different responses and how optimal UPR responses are achieved in physiological settings.

scholarly journals The unfolded protein response coordinates the production of endoplasmic reticulum protein and endoplasmic reticulum membrane.

1997 ◽  
Vol 8 (9) ◽  
pp. 1805-1814 ◽  
Author(s):  
J S Cox ◽  
R E Chapman ◽  
P Walter
Keyword(s):  
Endoplasmic Reticulum ◽  
Unfolded Protein Response ◽  
Secretory Pathway ◽  
Lipid Synthesis ◽  
Secretory Proteins ◽  
Endoplasmic Reticulum Membrane ◽  
Yeast Saccharomyces Cerevisiae ◽  
Unfolded Protein ◽  
The Unfolded Protein Response ◽  
Protein Response

The endoplasmic reticulum (ER) is a multifunctional organelle responsible for production of both lumenal and membrane components of secretory pathway compartments. Secretory proteins are folded, processed, and sorted in the ER lumen and lipid synthesis occurs on the ER membrane itself. In the yeast Saccharomyces cerevisiae, synthesis of ER components is highly regulated: the ER-resident proteins by the unfolded protein response and membrane lipid synthesis by the inositol response. We demonstrate that these two responses are intimately linked, forming different branches of the same pathway. Furthermore, we present evidence indicating that this coordinate regulation plays a role in ER biogenesis.

scholarly journals Class I histone deacetylases localize to the endoplasmic reticulum and modulate the unfolded protein response

2012 ◽  
Vol 26 (6) ◽  
pp. 2437-2445 ◽  
Author(s):  
Soumen Kahali ◽  
Bhaswati Sarcar ◽  
Antony Prabhu ◽  
Edward Seto ◽  
Prakash Chinnaiyan
Keyword(s):  
Endoplasmic Reticulum ◽  
Unfolded Protein Response ◽  
Histone Deacetylases ◽  
Class I ◽  
Unfolded Protein ◽  
The Unfolded Protein Response ◽  
Protein Response

scholarly journals A Role for the DnaJ Homologue Scj1p in Protein Folding in the Yeast Endoplasmic Reticulum

1998 ◽  
Vol 143 (4) ◽  
pp. 921-933 ◽  
Author(s):  
Susana Silberstein ◽  
Gabriel Schlenstedt ◽  
Pam A. Silver ◽  
Reid Gilmore
Keyword(s):  
Endoplasmic Reticulum ◽  
Unfolded Protein Response ◽  
Physiological Role ◽  
Carboxypeptidase Y ◽  
Reporter Protein ◽  
Unfolded Protein ◽  
A Cell ◽  
The Unfolded Protein Response ◽  
Protein Response

Members of the eukaryotic heat shock protein 70 family (Hsp70s) are regulated by protein cofactors that contain domains homologous to bacterial DnaJ. Of the three DnaJ homologues in the yeast rough endoplasmic reticulum (RER; Scj1p, Sec63p, and Jem1p), Scj1p is most closely related to DnaJ, hence it is a probable cofactor for Kar2p, the major Hsp70 in the yeast RER. However, the physiological role of Scj1p has remained obscure due to the lack of an obvious defect in Kar2p-mediated pathways in scj1 null mutants. Here, we show that the Δscj1 mutant is hypersensitive to tunicamycin or mutations that reduce N-linked glycosylation of proteins. Although maturation of glycosylated carboxypeptidase Y occurs with wild-type kinetics in Δscj1 cells, the transport rate for an unglycosylated mutant carboxypeptidase Y (CPY) is markedly reduced. Loss of Scj1p induces the unfolded protein response pathway, and results in a cell wall defect when combined with an oligosaccharyltransferase mutation. The combined loss of both Scj1p and Jem1p exaggerates the sensitivity to hypoglycosylation stress, leads to further induction of the unfolded protein response pathway, and drastically delays maturation of an unglycosylated reporter protein in the RER. We propose that the major role for Scj1p is to cooperate with Kar2p to mediate maturation of proteins in the RER lumen.

Sign in / Sign up

Export Citation Format

Share Document