PKB/Akt phosphorylation of ERRγ contributes to insulin-mediated inhibition of hepatic gluconeogenesis

Cited 33 time in scopus
Metadata Downloads
Title
PKB/Akt phosphorylation of ERRγ contributes to insulin-mediated inhibition of hepatic gluconeogenesis
Author(s)
D K Kim; Yong-Hoon Kim; D Hynx; Y Wang; K J Yang; D Ryu; K S Kim; E K Yoo; J S Kim; S H Koo; I K Lee; H Z Chae; J Park; Chul Ho Lee; S B Biddinger; B A Hemmings; H S Choi
Bibliographic Citation
Diabetologia, vol. 57, no. 12, pp. 2576-2585
Publication Year
2014
Abstract
AIMS/HYPOTHESIS: Insulin resistance, a major contributor to the pathogenesis of type 2 diabetes, leads to increased hepatic glucose production (HGP) owing to an impaired ability of insulin to suppress hepatic gluconeogenesis. Nuclear receptor oestrogen-related receptor γ (ERRγ) is a major transcriptional regulator of hepatic gluconeogenesis. In this study, we investigated insulin-dependent post-translational modifications (PTMs) altering the transcriptional activity of ERRγ for the regulation of hepatic gluconeogenesis. METHODS: We examined insulin-dependent phosphorylation and subcellular localisation of ERRγ in cultured cells and in the liver of C57/BL6, leptin receptor-deficient (db/db), liver-specific insulin receptor knockout (LIRKO) and protein kinase B (PKB) β-deficient (Pkbβ (-/-)) mice. To demonstrate the role of ERRγ in the inhibitory action of insulin on hepatic gluconeogenesis, we carried out an insulin tolerance test in C57/BL6 mice expressing wild-type or phosphorylation-deficient mutant ERRγ. RESULTS: We demonstrated that insulin suppressed the transcriptional activity of ERRγ by promoting PKB/Akt-mediated phosphorylation of ERRγ at S179 and by eliciting translocation of ERRγ from the nucleus to the cytoplasm through interaction with 14-3-3, impairing its ability to promote hepatic gluconeogenesis. In addition, db/db, LIRKO and Pkbβ (-/-) mice displayed enhanced ERRγ transcriptional activity due to a block in PKBβ-mediated ERRγ phosphorylation during refeeding. Finally, the phosphorylation-deficient mutant ERRγ S179A was resistant to the inhibitory action of insulin on HGP. CONCLUSIONS/INTERPRETATION: These results suggest that ERRγ is a major contributor to insulin action in maintaining hepatic glucose homeostasis.
Keyword
Akt/PKBHepatic gluconeogenesisInsulin receptor signallingNuclear hormone receptorPhosphorylation
ISSN
0012-186X
Publisher
Springer
DOI
http://dx.doi.org/10.1007/s00125-014-3366-x
Type
Article
Appears in Collections:
Ochang Branch Institute > Division of Bioinfrastructure > Laboratory Animal Resource Center > 1. Journal Articles
Files in This Item:
  • There are no files associated with this item.


Items in OpenAccess@KRIBB are protected by copyright, with all rights reserved, unless otherwise indicated.