Review Article

The ring-shaped hexameric helicases that function at DNA replication forks

  • Nature Structural & Molecular Biologyvolume 25pages122130 (2018)
  • doi:10.1038/s41594-018-0024-x
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DNA replication requires separation of genomic duplex DNA strands, an operation that is performed by a hexameric ring-shaped helicase in all domains of life. The structures and chemomechanical actions of these fascinating machines are coming into sharper focus. Although there is no evolutionary relationship between the hexameric helicases of bacteria and those of archaea and eukaryotes, they share many fundamental features. Here we review recent studies of these two groups of hexameric helicases and the unexpected distinctions they have also unveiled.

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We are grateful to N. Yao (Rockefeller University) and L. Bai (Van Andel Research Institute) for making some of the illustrations in this review. This work was supported by grants from the NIH (GM111472 and GM124170 (to H.L.) and GM115809 (to M.O’D.)), the Van Andel Research Institute (H.L.) and the Howard Hughes Medical Institute (M.O’D.). We thank members of the O’Donnell lab and the Li lab for their contribution to some of the studies described here.

Author information


  1. Department of DNA Replication, Rockefeller University and HHMI, New York, NY, USA

    • Michael E. O’Donnell
  2. Cryo-EM Structural Biology Laboratory, Van Andel Research Institute, Grand Rapids, MI, USA

    • Huilin Li


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The authors declare no competing financial interests.

Corresponding authors

Correspondence to Michael E. O’Donnell or Huilin Li.