The checkpoint Saccharomyces cerevisiae Rad9 protein contains a tandem tudor domain that recognizes DNA.

Nathalie Lancelot (1) , Gaëlle Charier (1) , Joël Couprie (1) , Isabelle Duband-Goulet (2) , Béatrice Alpha-Bazin (3) , Eric Quémeneur (3) , Emilie Ma (1) , Marie-Claude Marsolier-Kergoat (1) , Virginie Ropars (4) , Jean-Baptiste Charbonnier (1, 5) , Simona Miron (6) , Constantin T. Craescu (6) , Isabelle Callebaut (7) , Bernard Gilquin (1) , Sophie Zinn-Justin (1)

1 Institut de Biologie et Technologies de Saclay
2 IJM (UMR_7592) - Institut Jacques Monod
3 BIAM - Institut de Biosciences et Biotechnologies d'Aix-Marseille (ex-IBEB)
4 CBS - Centre de Biochimie Structurale [Montpellier]
5 PMTE - Protéines membranaires transductrices d'énergie
6 Imagerie intégrative de la molécule à l'organisme
7 IMPMC - Institut de minéralogie et de physique des milieux condensés

DNA damage checkpoints are signal transduction pathways that are activated after genotoxic insults to protect genomic integrity. At the site of DNA damage, 'mediator' proteins are in charge of recruiting 'signal transducers' to molecules 'sensing' the damage. Budding yeast Rad9, fission yeast Crb2 and metazoan 53BP1 are presented as mediators involved in the activation of checkpoint kinases. Here we show that, despite low sequence conservation, Rad9 exhibits a tandem tudor domain structurally close to those found in human/mouse 53BP1 and fission yeast Crb2. Moreover, this region is important for the resistance of Saccharomyces cerevisiae to different genotoxic stresses. It does not mediate direct binding to a histone H3 peptide dimethylated on K79, nor to a histone H4 peptide dimethylated on lysine 20, as was demonstrated for 53BP1. However, the tandem tudor region of Rad9 directly interacts with single-stranded DNA and double-stranded DNAs of various lengths and sequences through a positively charged region absent from 53BP1 and Crb2 but present in several yeast Rad9 homologs. Our results argue that the tandem tudor domains of Rad9, Crb2 and 53BP1 mediate chromatin binding next to double-strand breaks. However, their modes of chromatin recognition are different, suggesting that the corresponding interactions are differently regulated.

Domaines: Biochimie, Biologie Moléculaire

Nathalie Lancelot, Gaëlle Charier, Joël Couprie, Isabelle Duband-Goulet, Béatrice Alpha-Bazin, et al.. The checkpoint Saccharomyces cerevisiae Rad9 protein contains a tandem tudor domain that recognizes DNA.. Nucleic Acids Research, 2007, 35 (17), pp.5898-912. ⟨10.1093/nar/gkm607⟩. ⟨hal-00180974⟩