Structural basis of DNA crossover capture by DNA gyrase.
Fiche publication
Date publication
avril 2024
Journal
Science (New York, N.Y.)
Auteurs
Membres identifiés du Cancéropôle Est :
Dr LAMOUR Valérie
Tous les auteurs :
Vayssières M, Marechal N, Yun L, Lopez Duran B, Murugasamy NK, Fogg JM, Zechiedrich L, Nadal M, Lamour V
Lien Pubmed
Résumé
DNA supercoiling must be precisely regulated by topoisomerases to prevent DNA entanglement. The interaction of type IIA DNA topoisomerases with two DNA molecules, enabling the transport of one duplex through the transient double-stranded break of the other, remains elusive owing to structures derived solely from single linear duplex DNAs lacking topological constraints. Using cryo-electron microscopy, we solved the structure of DNA gyrase bound to a negatively supercoiled minicircle DNA. We show how DNA gyrase captures a DNA crossover, revealing both conserved molecular grooves that accommodate the DNA helices. Together with molecular tweezer experiments, the structure shows that the DNA crossover is of positive chirality, reconciling the binding step of gyrase-mediated DNA relaxation and supercoiling in a single structure.
Référence
Science. 2024 04 12;384(6692):227-232