SIRT7 represses Myc activity to suppress ER stress and prevent fatty liver disease

Cell Rep. 2013 Nov 14;5(3):654-665. doi: 10.1016/j.celrep.2013.10.007. Epub 2013 Nov 7.

Abstract

Nonalcoholic fatty liver disease is the most common chronic liver disorder in developed countries. Its pathogenesis is poorly understood, and therapeutic options are limited. Here, we show that SIRT7, an NAD(+)-dependent H3K18Ac deacetylase, functions at chromatin to suppress ER stress and prevent the development of fatty liver disease. SIRT7 is induced upon ER stress and is stabilized at the promoters of ribosomal proteins through its interaction with the transcription factor Myc to silence gene expression and to relieve ER stress. SIRT7-deficient mice develop chronic hepatosteatosis resembling human fatty liver disease. Myc inactivation or pharmacological suppression of ER stress alleviates fatty liver caused by SIRT7 deficiency. Importantly, SIRT7 suppresses ER stress and reverts the fatty liver disease in diet-induced obese mice. Our study identifies SIRT7 as a cofactor of Myc for transcriptional repression and delineates a druggable regulatory branch of the ER stress response that prevents and reverts fatty liver disease.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Endoplasmic Reticulum Stress / physiology*
  • Fatty Liver / metabolism*
  • Female
  • Genes, myc
  • HEK293 Cells
  • Hep G2 Cells
  • Humans
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Non-alcoholic Fatty Liver Disease
  • Proto-Oncogene Proteins c-myc / antagonists & inhibitors
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism*
  • Sirtuins / deficiency
  • Sirtuins / genetics
  • Sirtuins / metabolism*
  • Transfection

Substances

  • Proto-Oncogene Proteins c-myc
  • SIRT7 protein, human
  • Sirt7 protein, mouse
  • Sirtuins