The DNA repair complex Ku70/86 modulates Apaf1 expression upon DNA damage

Abstract

Apaf1 is a key regulator of the mitochondrial intrinsic pathway of apoptosis, as it activates executioner caspases by forming the apoptotic machinery apoptosome. Its genetic regulation and its post-translational modification are crucial under the various conditions where apoptosis occurs. Here we describe Ku70/86, a mediator of non-homologous end-joining pathway of DNA repair, as a novel regulator of Apaf1 transcription. Through analysing different Apaf1 promoter mutants, we identified an element repressing the Apaf1 promoter. We demonstrated that Ku70/86 is a nuclear factor able to bind this repressing element and downregulating Apaf1 transcription. We also found that Ku70/86 interaction with Apaf1 promoter is dynamically modulated upon DNA damage. The effect of this binding is a downregulation of Apaf1 expression immediately following the damage to DNA; conversely, we observed Apaf1 upregulation and apoptosis activation when Ku70/86 unleashes the Apaf1-repressing element. Therefore, besides regulating DNA repair, our results suggest that Ku70/86 binds to the Apaf1 promoter and represses its activity. This may help to inhibit the apoptosome pathway of cell death and contribute to regulate cell survival.


Autore Pugliese

Tutti gli autori

  • De Zio D. , Bordi M. , Tino E. , Lanzuolo C. , Ferraro E. , Mora E. , Ciccosanti F. , Fimia G. M. , Orlando V. , Cecconi F.

Titolo volume/Rivista

CELL DEATH AND DIFFERENTIATION


Anno di pubblicazione

2011

ISSN

1476-5403

ISBN

Non Disponibile


Numero di citazioni Wos

13

Ultimo Aggiornamento Citazioni

25/04/2018


Numero di citazioni Scopus

13

Ultimo Aggiornamento Citazioni

26/04/2018


Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile