Plant gammaH2AX foci are required for proper DNA DSB repair responses and colocalize with E2F factors.
Fiche publication
Date publication
avril 2012
Auteurs
Membres identifiés du Cancéropôle Est :
Pr SCHMIT Anne-Catherine
Tous les auteurs :
Lang J, Smetana O, Sanchez-Calderon L, Lincker F, Genestier J, Schmit AC, Houlne G, Chaboute ME
Lien Pubmed
Résumé
Cellular responses to DNA double-strand breaks (DSBs) are linked in mammals and yeasts to the phosphorylated histones H2AX (gammaH2AX) repair foci which are multiproteic nuclear complexes responsible for DSB sensing and signalling. However, neither the components of these foci nor their role are yet known in plants. In this paper, we describe the effects of gammaH2AX deficiency in Arabidopsis thaliana plants challenged with DSBs in terms of genotoxic sensitivity and E2F-mediated transcriptional responses. We further establish the existence, restrictive to the G1/S transition, of specific DSB-induced foci containing tobacco E2F transcription factors, in both A. thaliana roots and BY-2 tobacco cells. These E2F foci partially colocalize with gammaH2AX foci while their formation is ataxia telangiectasia mutated (ATM)-dependent, requires the E2F transactivation domain with its retinoblastoma-binding site and is optimal in the presence of functional H2AXs. Overall, our results unveil a new interplay between plant H2AX and E2F transcriptional activators during the DSB response.
Référence
New Phytol. 2012 Apr;194(2):353-63