Titre
Holliday junction resolution in human cells: two junction endonucleases with distinct substrate specificities
Type
article
Institution
UNIL/CHUV/Unisanté + institutions partenaires
Périodique
Auteur(s)
Constantinou, A.
Auteure/Auteur
Chen, X. B.
Auteure/Auteur
McGowan, C. H.
Auteure/Auteur
West, S. C.
Auteure/Auteur
Liens vers les personnes
Liens vers les unités
ISSN
0261-4189
Statut éditorial
Publié
Date de publication
2002-10
Volume
21
Numéro
20
Première page
5577
Dernière page/numéro d’article
85
Notes
In Vitro
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Oct 15
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Oct 15
Résumé
Enzymatic activities that cleave Holliday junctions are required for the resolution of recombination intermediates and for the restart of stalled replication forks. Here we show that human cell-free extracts possess two distinct endonucleases that can cleave Holliday junctions. The first cleaves Holliday junctions in a structure- and sequence-specific manner, and associates with an ATP-dependent branch migration activity. Together, these activities promote branch migration/resolution reactions similar to those catalysed by the Escherichia coli RuvABC resolvasome. Like RuvC-mediated resolution, the products can be religated. The second, containing Mus81 protein, cuts Holliday junctions but the products are mostly non-ligatable. Each nuclease has a defined substrate specificity: the branch migration-associated resolvase is highly specific for Holliday junctions, whereas the Mus81-associated endonuclease is one order of magnitude more active upon replication fork and 3'-flap structures. Thus, both nucleases are capable of cutting Holliday junctions formed during recombination or through the regression of stalled replication forks. However, the Mus81-associated endonuclease may play a more direct role in replication fork collapse by catalysing the cleavage of stalled fork structures.
Sujets
PID Serval
serval:BIB_CE9088615EC2
PMID
Open Access
Oui
Date de création
2008-01-24T13:50:55.238Z
Date de création dans IRIS
2025-05-21T00:21:10Z