Small RNA-mediated repair of UV-induced DNA lesions by the DNA DAMAGE-BINDING PROTEIN 2 and ARGONAUTE 1.

Fiche publication

Date publication

avril 2017

Journal

Proceedings of the National Academy of Sciences of the United States of America

Auteurs

Membres identifiés du Cancéropôle Est :
Mme COGNAT Valérie

Tous les auteurs :
Schalk C, Cognat V, Graindorge S, Vincent T, Voinnet O, Molinier J

Lien Pubmed

https://www.ncbi.nlm.nih.gov/pubmed/28325872

Résumé

As photosynthetic organisms, plants need to prevent irreversible UV-induced DNA lesions. Through an unbiased, genome-wide approach, we have uncovered a previously unrecognized interplay between Global Genome Repair and small interfering RNAs (siRNAs) in the recognition of DNA photoproducts, prevalently in intergenic regions. Genetic and biochemical approaches indicate that, upon UV irradiation, the DNA DAMAGE-BINDING PROTEIN 2 (DDB2) and ARGONAUTE 1 (AGO1) of form a chromatin-bound complex together with 21-nt siRNAs, which likely facilitates recognition of DNA damages in an RNA/DNA complementary strand-specific manner. The biogenesis of photoproduct-associated siRNAs involves the noncanonical, concerted action of RNA POLYMERASE IV, RNA-DEPENDENT RNA POLYMERASE-2, and DICER-LIKE-4. Furthermore, the chromatin association/dissociation of the DDB2-AGO1 complex is under the control of siRNA abundance and DNA damage signaling. These findings reveal unexpected nuclear functions for DCL4 and AGO1, and shed light on the interplay between small RNAs and DNA repair recognition factors at damaged sites.