Dynamic partnership between TFIIH, PGC-1α and SIRT1 is impaired in trichothiodystrophy

PLoS Genet. 2014 Oct 23;10(10):e1004732. doi: 10.1371/journal.pgen.1004732. eCollection 2014 Oct.

Abstract

The expression of protein-coding genes requires the selective role of many transcription factors, whose coordinated actions remain poorly understood. To further grasp the molecular mechanisms that govern transcription, we focused our attention on the general transcription factor TFIIH, which gives rise, once mutated, to Trichothiodystrophy (TTD), a rare autosomal premature-ageing disease causing inter alia, metabolic dysfunctions. Since this syndrome could be connected to transcriptional defects, we investigated the ability of a TTD mouse model to cope with food deprivation, knowing that energy homeostasis during fasting involves an accurate regulation of the gluconeogenic genes in the liver. Abnormal amounts of gluconeogenic enzymes were thus observed in TTD hepatic parenchyma, which was related to the dysregulation of the corresponding genes. Strikingly, such gene expression defects resulted from the inability of PGC1-α to fulfill its role of coactivator. Indeed, extensive molecular analyses unveiled that wild-type TFIIH cooperated in an ATP-dependent manner with PGC1-α as well as with the deacetylase SIRT1, thereby contributing to the PGC1-α deacetylation by SIRT1. Such dynamic partnership was, however, impaired when TFIIH was mutated, having as a consequence the disruption of PGC1-α recruitment to the promoter of target genes. Therefore, besides a better understanding of the etiology of TFIIH-related disease, our results shed light on the synergistic relationship that exist between different types of transcription factors, which is necessary to properly regulate the expression of protein coding genes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • DNA Repair / genetics
  • Gene Expression Regulation
  • Hepatocytes / metabolism
  • Hepatocytes / pathology
  • Humans
  • Mice
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Sirtuin 1 / biosynthesis
  • Sirtuin 1 / genetics*
  • Transcription Factor TFIIH / biosynthesis
  • Transcription Factor TFIIH / genetics*
  • Transcription Factors / biosynthesis
  • Transcription Factors / genetics*
  • Transcription, Genetic*
  • Trichothiodystrophy Syndromes / genetics*
  • Trichothiodystrophy Syndromes / pathology

Substances

  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Ppargc1a protein, mouse
  • Transcription Factors
  • Transcription Factor TFIIH
  • Sirt1 protein, mouse
  • Sirtuin 1

Grants and funding

This study was supported by the Association Nationale des Membres de l'Ordre National du Mérite, the French National Research Agency (ANR-05-PCOD-032, ANR-10-BLANC-1231-02, ANR-12-BSV8-0017), the ARC French Foundation for Cancer Research and a European Research Council Advanced Grant. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.