Skip to Main content Skip to Navigation
Journal articles

Interactome Screening Identifies the ER Luminal Chaperone Hsp47 as a Regulator of the Unfolded Protein Response Transducer IRE1 alpha

Abstract : Maintenance of endoplasmic reticulum (ER) proteostasis is controlled by a dynamic signaling network known as the unfolded protein response (UPR). IRE1α is a major UPR transducer, determining cell fate under ER stress. We used an interactome screening to unveil several regulators of the UPR, highlighting the ER chaperone Hsp47 as the major hit. Cellular and biochemical analysis indicated that Hsp47 instigates IRE1α signaling through a physical interaction. Hsp47 directly binds to the ER luminal domain of IRE1α with high affinity, displacing the negative regulator BiP from the complex to facilitate IRE1α oligomerization. The regulation of IRE1α signaling by Hsp47 is evolutionarily conserved as validated using fly and mouse models of ER stress. Hsp47 deficiency sensitized cells and animals to experimental ER stress, revealing the significance of Hsp47 to global proteostasis maintenance. We conclude that Hsp47 adjusts IRE1α signaling by fine-tuning the threshold to engage an adaptive UPR.
Document type :
Journal articles
Complete list of metadatas

https://hal-univ-rennes1.archives-ouvertes.fr/hal-01710048
Contributor : Laurent Jonchère <>
Submitted on : Thursday, February 15, 2018 - 3:25:01 PM
Last modification on : Monday, October 12, 2020 - 10:28:18 AM

Links full text

Identifiers

Citation

Denisse Sepulveda, Diego Rojas-Rivera, Diego A. Rodriguez, Jody Groenendyk, Andres Kohler, et al.. Interactome Screening Identifies the ER Luminal Chaperone Hsp47 as a Regulator of the Unfolded Protein Response Transducer IRE1 alpha. Molecular Cell, Elsevier, 2018, 69 (2), pp.238-252.e7. ⟨10.1016/j.molcel.2017.12.028⟩. ⟨hal-01710048⟩

Share

Metrics

Record views

512