Structure of the hexameric HerA ATPase reveals a mechanism of translocation-coupled DNA-end processing in archaea

DOI: 10.1038/ncomms6506
PMID: 25420454

Authors: Neil J. Rzechorzek (University of Cambridge) , John K. Blackwood (University of Cambridge) , Sian M. Bray (University of Cambridge) , Joseph D. Maman (University of Cambridge) , Luca Pellegrini (University of Cambridge) , Nicholas P. Robinson (University of Cambridge)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nature Communications , VOL 5

State: Published (Approved)
Published: November 2014

Abstract: The ​HerA ATPase cooperates with the ​NurA nuclease and the ​Mre11–​Rad50 complex for the repair of double-strand DNA breaks in thermophilic archaea. Here we extend our structural knowledge of this minimal end-resection apparatus by presenting the first crystal structure of hexameric ​HerA. The full-length structure visualizes at atomic resolution the N-terminal HerA-ATP synthase domain and a conserved C-terminal extension, which acts as a physical brace between adjacent protomers. The brace also interacts in trans with nucleotide-binding residues of the neighbouring subunit. Our observations support a model in which the coaxial interaction of the ​HerA ring with the toroidal ​NurA dimer generates a continuous channel traversing the complex. ​HerA-driven translocation would propel the DNA towards the narrow annulus of ​NurA, leading to duplex melting and nucleolytic digestion. This system differs substantially from the bacterial end-resection paradigms. Our findings suggest a novel mode of DNA-end processing by this integrated archaeal helicase–nuclease machine.

Diamond Keywords: Archaea

Subject Areas: Biology and Bio-materials


Instruments: I02-Macromolecular Crystallography

Added On: 18/11/2015 14:30

Discipline Tags:

Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)