Gamma rays induce a p53-independent mitochondrial biogenesis that is counter-regulated by HIF1?.

Abstract

Mitochondrial biogenesis is an orchestrated process that presides to the regulation of the organelles homeostasis within a cell. We show that ?-rays, at doses commonly used in the radiation therapy for cancer treatment, induce an increase in mitochondrial mass and function, in response to a genotoxic stress that pushes cells into senescence, in the presence of a functional p53. Although the main effector of the response to ?-rays is the p53-p21 axis, we demonstrated that mitochondrial biogenesis is only indirectly regulated by p53, whose activation triggers a murine double minute 2 (MDM2)-mediated hypoxia-inducible factor 1? (HIF1?) degradation, leading to the release of peroxisome-proliferator activated receptor gamma co-activator 1? inhibition by HIF1?, thus promoting mitochondrial biogenesis. Mimicking hypoxia by HIF1? stabilization, in fact, blunts the mitochondrial response to ?-rays as well as the induction of p21-mediated cell senescence, indicating prevalence of the hypoxic over the genotoxic response. Finally, we also show in vivo that post-radiotherapy mitochondrial DNA copy number increase well correlates with lack of HIF1? increase in the tissue, concluding this may be a useful molecular tool to infer the trigger of a hypoxic response during radiotherapy, which may lead to failure of activation of cell senescence.


Tutti gli autori

  • Bartoletti-Stella A.; Mariani E.; Kurelac I.; Maresca A.; Caratozzolo M.F.; Iommarini L.; Carelli V.; Eusebi L.H.; Guido A.; Cenacchi G.; Fuccio L.; Rugolo M.; Tullo A.; Porcelli A.M.; Gasparre G.

Titolo volume/Rivista

Cell death and disease


Anno di pubblicazione

2013

ISSN

2041-4889

ISBN

Non Disponibile


Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

Non Disponibile


Numero di citazioni Scopus

Non Disponibile

Ultimo Aggiornamento Citazioni

Non Disponibile


Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile