Direct link between metabolic regulation and the heat-shock response through the transcriptional regulator PGC-1α

Proc Natl Acad Sci U S A. 2015 Oct 20;112(42):E5669-78. doi: 10.1073/pnas.1516219112. Epub 2015 Oct 5.

Abstract

In recent years an extensive effort has been made to elucidate the molecular pathways involved in metabolic signaling in health and disease. Here we show, surprisingly, that metabolic regulation and the heat-shock/stress response are directly linked. Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a critical transcriptional coactivator of metabolic genes, acts as a direct transcriptional repressor of heat-shock factor 1 (HSF1), a key regulator of the heat-shock/stress response. Our findings reveal that heat-shock protein (HSP) gene expression is suppressed during fasting in mouse liver and in primary hepatocytes dependent on PGC-1α. HSF1 and PGC-1α associate physically and are colocalized on several HSP promoters. These observations are extended to several cancer cell lines in which PGC-1α is shown to repress the ability of HSF1 to activate gene-expression programs necessary for cancer survival. Our study reveals a surprising direct link between two major cellular transcriptional networks, highlighting a previously unrecognized facet of the activity of the central metabolic regulator PGC-1α beyond its well-established ability to boost metabolic genes via its interactions with nuclear hormone receptors and nuclear respiratory factors. Our data point to PGC-1α as a critical repressor of HSF1-mediated transcriptional programs, a finding with possible implications both for our understanding of the full scope of metabolically regulated target genes in vivo and, conceivably, for therapeutics.

Keywords: metabolism; stress response; transcription.

Publication types

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

MeSH terms

  • Animals
  • Cell Line
  • DNA-Binding Proteins / physiology
  • Gene Expression / physiology
  • Heat Shock Transcription Factors
  • Heat-Shock Response*
  • Humans
  • Liver / cytology
  • Liver / metabolism
  • Mice
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Promoter Regions, Genetic
  • Transcription Factors / physiology*
  • Transcription, Genetic / physiology

Substances

  • DNA-Binding Proteins
  • Heat Shock Transcription Factors
  • Hsf1 protein, mouse
  • PPARGC1A protein, human
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Ppargc1a protein, mouse
  • Transcription Factors

Associated data

  • GEO/GSE51498