Fortilin binds IRE1α and prevents ER stress from signaling apoptotic cell death

Autor: Ken Fujise, Matthew D. King, Heather L. Stevenson, Decha Pinkaew, Patuma Sinthujaroen, Zhihe Liu, Owen M. McDougal, Abhijnan Chattopadhyay, Yanjie Chen, Preedakorn Chunhacha
Rok vydání: 2017
Předmět:
0301 basic medicine
Science
Endoribonuclease
General Physics and Astronomy
Apoptosis
Protein Serine-Threonine Kinases
Biology
Endoplasmic Reticulum
Article
General Biochemistry
Genetics and Molecular Biology

Mice
eIF-2 Kinase
03 medical and health sciences
Transduction
Genetic

Cell Line
Tumor

Endoribonucleases
Biomarkers
Tumor

Animals
Humans
Endoplasmic Reticulum Chaperone BiP
Heat-Shock Proteins
Osteoblasts
Multidisciplinary
ATF6
Kinase
Endoplasmic reticulum
Tumor Protein
Translationally-Controlled 1

Epithelial Cells
General Chemistry
Endoplasmic Reticulum Stress
Activating Transcription Factor 6
3. Good health
Cell biology
030104 developmental biology
Gene Expression Regulation
Cytoplasm
Unfolded Protein Response
Unfolded protein response
Apoptotic signaling pathway
Signal transduction
Signal Transduction
Zdroj: Nature Communications
Nature Communications, Vol 8, Iss 1, Pp 1-16 (2017)
ISSN: 2041-1723
Popis: The endoplasmic reticulum, the cytoplasmic organelle that matures a massive amount of nascent secretory polypeptides, is particularly sensitive to stress. Endoplasmic reticulum stress causes unfolded proteins to populate the organelle, eliciting the unfolded protein response. During the unfolded protein response, GRP78—an endoplasmic reticulum master stress regulator—detaches from three endoplasmic reticulum stress sensors (IRE1α, PERK, and ATF6) and allows them to activate the apoptotic signaling pathway. Fortilin, a pro-survival molecule, is known to inhibit apoptosis by binding and inhibiting p53, but its role in endoplasmic reticulum stress-induced apoptosis remains unknown. Here, we report that fortilin directly interacts with the cytoplasmic domain of IRE1α, inhibits both kinase and endoribonuclease (RNase) activities of the stress sensor, and protects cells against apoptotic cell death at both cellular and whole animal levels. Our data support a role of fortilin in the unfolded protein response and its potential participation in human diseases caused by unfolded protein response.
IRE1α is an ER stress sensor, whose activity induces apoptosis. Here, the authors report that fortilin, a pro-survival factor, with yet unknown roles in ER stress, interacts with active IRE1α, inhibits both its kinase end RNase activities, and protects cells from apoptosis both in vitro and in vivo.
Databáze: OpenAIRE