期刊
NUCLEIC ACIDS RESEARCH
卷 47, 期 11, 页码 5712-5722出版社
OXFORD UNIV PRESS
DOI: 10.1093/nar/gkz248
关键词
-
资金
- Sven and Lilly Lawski Foundation
- Insamlingsstiftelsen for medicinsk forskning
- Carl Tryggers stiftelse
- Swedish Cancer Foundation
- Swedish Research Council
DNA polymerase epsilon (Pol epsilon), the major leading-strand DNA polymerase in eukaryotes, has a catalytic subunit (Pol2) and three non-catalytic subunits. The N-terminal half of Pol2 (Pol2(CORE)) exhibits both polymerase and exonuclease activity. It has been suggested that both the non-catalytic C-terminal domain of Pol2 (with the two cysteine motifs CysA and CysB) and Pol2(CORE) (with the CysX cysteine motif) are likely to coordinate an Fe-S cluster. Here, we present two new crystal structures of Pol2(CORE) with an Fe-S cluster bound to the CysX motif, supported by an anomalous signal at that position. Furthermore we show that purified four-subunit Pol epsilon, Pol epsilon CysA(MUT) (C2111S/C2133S), and Pol epsilon CysB(MUT) (C2167S/C2181S) all have an Fe-S cluster that is not present in Pol epsilon CysX(MUT) (C665S/C668S). Pol epsilon CysA(MUT) and Pol epsilon CysB(MUT) behave similarly to wildtype Pol epsilon in in vitro assays, but Pol epsilon CysX(MUT) has severely compromised DNA polymerase activity that is not the result of an excessive exonuclease activity. Tetrad analyses show that haploid yeast strains carrying CysX(MUT) are inviable. In conclusion, Pol epsilon has a single Fe-S cluster bound at the base of the P-domain, and this Fe-S cluster is essential for cell viability and polymerase activity.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据