CaltechAUTHORS
  A Caltech Library Service

The protein kinase PERK/EIF2AK3 regulates proinsulin processing not via protein synthesis but by controlling endoplasmic reticulum chaperones

Sowers, Carrie R. and Wang, Rong and Bourne, Rebecca A. and McGrath, Barbara C. and Hu, Jingjie and Bevilacqua, Sarah C. and Paton, James C. and Paton, Adrienne W. and Collardeau-Frachon, Sophie and Nicolino, Marc and Cavener, Douglas R. (2018) The protein kinase PERK/EIF2AK3 regulates proinsulin processing not via protein synthesis but by controlling endoplasmic reticulum chaperones. Journal of Biological Chemistry, 293 (14). pp. 5134-5149. ISSN 0021-9258. http://resolver.caltech.edu/CaltechAUTHORS:20180220-110902998

[img] PDF - Supplemental Material
See Usage Policy.

1370Kb

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20180220-110902998

Abstract

Loss-of-function mutations of the protein kinase PERK (EIF2AK3) in humans and mice cause permanent neonatal diabetes and severe proinsulin aggregation in the endoplasmic reticulum (ER), highlighting the essential role of PERK in insulin production in pancreatic β cells. As PERK is generally known as a translational regulator of the unfolded protein response (UPR), the underlying cause of these β cell defects has often been attributed to derepression of proinsulin synthesis, resulting in proinsulin overload in the ER. Using high-resolution imaging and standard protein fractionation and immunological methods we have examined the PERK-dependent phenotype more closely. We found that whereas proinsulin aggregation requires new protein synthesis, global protein and proinsulin synthesis are down-regulated in PERK-inhibited cells, strongly arguing against proinsulin overproduction being the root cause of their aberrant ER phenotype. Furthermore, we show that PERK regulates proinsulin proteostasis by modulating ER chaperones, including BiP and ERp72. Transgenic overexpression of BiP and BiP knockdown (KD) both promoted proinsulin aggregation, whereas ERp72 overexpression and knockdown rescued it. These findings underscore the importance of ER chaperones working in concert to achieve control of insulin production and identify a role for PERK in maintaining a functional balance among these chaperones.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/ doi:10.1074/jbc.M117.813790DOIArticle
http://www.jbc.org/content/293/14/5134PublisherArticle
http://www.jbc.org/content/293/14/5134/suppl/DC1PublisherSupporting Information
ORCID:
AuthorORCID
Collardeau-Frachon, Sophie0000-0001-8604-1089
Nicolino, Marc0000-0001-5395-2249
Cavener, Douglas R.0000-0002-1558-7137
Additional Information:© 2018 American Society for Biochemistry and Molecular Biology. Received August 21, 2017. Accepted February 14, 2018. First Published on February 14, 2018. We thank Dr. Jeff Axten and Dr. Rakesh Kumar for providing the GSK2606414 PERK inhibitor and discussions about the effects of PERK inhibition. We thank Dr. Christopher Newgard, Dr. Scott Kimball, Dr. Jun-Ichi Miyazaki, Dr. Allen Volchuk, and Dr. Anne Bertolotti for providing experimental materials. This work was supported by National Institutes of Health Grant R01 DK88140 and a Huck Graduate Research Dissertation Award (to C. R. S.) from the Huck Institutes of the Life Sciences at Penn State University. The authors declare that they have no conflicts of interest with the contents of this article. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Author contributions: Conceptualization, C. R. S., R. W., J. H., B. C. M., D. R.C.; methodology, C. R. S., R. W., J. H., R. A. B., B. C. M., D. R. C.; validation, C. R. S., R. W., J. H., R. A. B., B. C. M., D. R. C.; formal analysis, C. R. S., R. W., J. H., R. A. B.; investigation, C. R. S., R. W., J. H., S. C. B., R. A. B., B. C. M.; resources, J. C. P., A. W. P., S. C-F., M. N.; writing/original draft, C. R. S., R. W.; writing/review and editing, C. R. S., B. C. M., R. A. B., D. R. C.; visualization? C. R. S.; funding acquisition, C. R. S., B. C. M., and D. R. C.
Funders:
Funding AgencyGrant Number
NIHR01 DK88140
Pennsylvania State UniversityUNSPECIFIED
Subject Keywords:chaperone; endoplasmic reticulum (ER); insulin secretion; intracellular trafficking; protein aggregation; BiP; PERK; beta cells
Record Number:CaltechAUTHORS:20180220-110902998
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20180220-110902998
Official Citation:Carrie R. Sowers, Rong Wang, Rebecca A. Bourne, Barbara C. McGrath, Jingjie Hu, Sarah C. Bevilacqua, James C. Paton, Adrienne W. Paton, Sophie Collardeau-Frachon, Marc Nicolino, and Douglas R. Cavener The protein kinase PERK/EIF2AK3 regulates proinsulin processing not via protein synthesis but by controlling endoplasmic reticulum chaperones J. Biol. Chem. 2018 293: 5134-. doi:10.1074/jbc.M117.813790
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:84892
Collection:CaltechAUTHORS
Deposited By: Ruth Sustaita
Deposited On:22 Feb 2018 05:02
Last Modified:25 Apr 2018 21:27

Repository Staff Only: item control page