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Structural insights into Cdc45 function: was there a nuclease at the heart of the ancestral replisome?

ABSTRACT: The role of Cdc45 in genomic duplication has remained unclear since its initial identification as an essential replication factor. Recent structural studies of Cdc45 and the evolutionarily-related archaeal GAN and bacterial RecJ nucleases have provided fresh insight into its function as co-activator of the MCM helicase. The CMG helicase of the last archaeal/eukaryotic ancestor might have harboured a single-stranded DNA nuclease activity, conserved in some modern archaea.

SUBMITTER: Pellegrini L

PROVIDER: S-EPMC5484177 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Structural insights into Cdc45 function: was there a nuclease at the heart of the ancestral replisome?

Pellegrini Luca L

Biophysical chemistry 20161127

The role of Cdc45 in genomic duplication has remained unclear since its initial identification as an essential replication factor. Recent structural studies of Cdc45 and the evolutionarily-related archaeal GAN and bacterial RecJ nucleases have provided fresh insight into its function as co-activator of the MCM helicase. The CMG helicase of the last archaeal/eukaryotic ancestor might have harboured a single-stranded DNA nuclease activity, conserved in some modern archaea. ...[more]

PMID: 27919598

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