Netz DJA, Stith CM, Stümpfig M, Köpf G, Vogel D, Genau HM, Stodola JL, Lill R, Burgers PMJ, Pierik AJ. Eukaryotic DNA polymerases require an iron-sulfur cluster for the formation of active complexes.
Nat Chem Biol 2011;
8:125-32. [PMID:
22119860 PMCID:
PMC3241888 DOI:
10.1038/nchembio.721]
[Citation(s) in RCA: 292] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 10/03/2011] [Indexed: 11/09/2022]
Abstract
The eukaryotic replicative DNA polymerases (Pol α, δ and ɛ) and the major DNA mutagenesis enzyme Pol ζ contain two conserved cysteine-rich metal-binding motifs (CysA and CysB) in the C-terminal domain (CTD) of their catalytic subunits. Here we demonstrate by in vivo and in vitro approaches the presence of an essential [4Fe-4S] cluster in the CysB motif of all four yeast B-family DNA polymerases. Loss of the [4Fe-4S] cofactor by cysteine ligand mutagenesis in Pol3 destabilized the CTD and abrogated interaction with the Pol31 and Pol32 subunits. Reciprocally, overexpression of accessory subunits increased the amount of the CTD-bound Fe-S cluster. This implies an important physiological role of the Fe-S cluster in polymerase complex stabilization. Further, we demonstrate that the Zn-binding CysA motif is required for PCNA-mediated Pol δ processivity. Together, our findings show that the function of eukaryotic replicative DNA polymerases crucially depends on different metallocenters for accessory subunit recruitment and replisome stability.
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