Abstract
The core nonhomologous end-joining DNA repair pathway is composed of seven factors: Ku70, Ku80, DNA-PKcs, Artemis, XRCC4 (X4), DNA ligase IV (L4), and Cernunnos/XLF (Cernunnos). Although Cernunnos and X4 are structurally related and participate in the same complex together with L4, they have distinct functions during DNA repair. L4 relies on X4 but not on Cernunnos for its stability, and L4 is required for optimal interaction of Cernunnos with X4. We demonstrate here, using in vitro-generated Cernunnos mutants and a series of functional assays in vivo, that the C-terminal region of Cernunnos is dispensable for its activity during DNA repair.
SUPPLEMENTAL MATERIAL
Supplemental material for this article may be found at http://mcb.asm.org/ .
ACKNOWLEDGMENTS
This work was supported by institutional grants from INSERM as well as by grants from the Ligue National contre le Cancer (Equipe labelisée La Ligue), the INCa/Cancéropôle IdF, the Agence Nationale pour la Recherche (ANR'06), and the Commissariat à l'Energie Atomique (LRC-CEA 40V). L.M. is supported by MENRT and P.R.-M. by the Association pour la Recherche sur le Cancer. P.R. is a scientist from the Centre National de la Recherche Scientifique.