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Iron-Sulfur Clusters in DNA Polymerases and Primases of Eukaryotes.

ABSTRACT: Research during the past decade witnessed the discovery of [4Fe-4S] clusters in several members of the eukaryotic DNA replication machinery. The presence of clusters was confirmed by UV-visible absorption, electron paramagnetic resonance spectroscopy, and metal analysis for primase and the B-family DNA polymerases ? and ?. The crystal structure of primase revealed that the [4Fe-4S] cluster is buried inside the protein and fulfills a structural role. Although [4Fe-4S] clusters are firmly established in the C-terminal domains of catalytic subunits of DNA polymerases ? and ?, no structures are currently available and their precise roles have not been ascertained. The [4Fe-4S] clusters in the polymerases and primase play a structural role ensuring proper protein folding and stability. In DNA polymerases ? and ?, they can potentially play regulatory role by sensing hurdles during DNA replication and assisting with DNA polymerase switches by oscillation between oxidized-reduced states.

SUBMITTER: Baranovskiy AG

PROVIDER: S-EPMC5947875 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Iron-Sulfur Clusters in DNA Polymerases and Primases of Eukaryotes.

Baranovskiy Andrey G AG Siebler Hollie M HM Pavlov Youri I YI Tahirov Tahir H TH

Methods in enzymology 20171206

Research during the past decade witnessed the discovery of [4Fe-4S] clusters in several members of the eukaryotic DNA replication machinery. The presence of clusters was confirmed by UV-visible absorption, electron paramagnetic resonance spectroscopy, and metal analysis for primase and the B-family DNA polymerases δ and ζ. The crystal structure of primase revealed that the [4Fe-4S] cluster is buried inside the protein and fulfills a structural role. Although [4Fe-4S] clusters are firmly establis ...[more]

PMID: 29746236

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