, Volume 122, Issue 1–2, pp 47–53 | Cite as

Structure and evolutionary origins of the CMG complex

  • Silvia Onesti
  • Stuart A. MacNeillEmail author


The CMG (Cdc45–MCM–GINS) complex is the eukaryotic replicative helicase, the enzyme that unwinds double-stranded DNA at replication forks. All three components of the CMG complex are essential for its function, but only in the case of MCM, the molecular motor that harnesses the energy of ATP hydrolysis to catalyse strand separation, is that function clear. Here, we review current knowledge of the three-dimensional structure of the CMG complex and its components and highlight recent advances in our understanding of its evolutionary origins.


DNA replication DNA helicase CMG MCM GINS Cdc45 



We thank our colleagues in St Andrews, Trieste and elsewhere for their help in the preparation of this review. Work in our laboratories is funded by the Scottish Universities Life Sciences Alliance (SULSA) and by the Associazione Italiana per la Ricerca sul Cancro (AIRC IG10646).


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Structural Biology LaboratoryElettra-Sincrotrone TriesteTriesteItaly
  2. 2.Biomedical Sciences Research ComplexUniversity of St AndrewsSt AndrewsUK

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