The GINS Complex from Pyrococcus furiosus Stimulates the MCM Helicase Activity*
The GINS Complex from Pyrococcus furiosus Stimulates the MCM Helicase Activity*
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DOI：
10.1074/jbc.m707654200
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发表时间：
2008-01
影响因子：
4.8
通讯作者：
Takehiro Yoshimochi;R. Fujikane;M. kawanami;F. Matsunaga;Y. Ishino
中科院分区：
文献类型：
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作者：
Takehiro Yoshimochi;R. Fujikane;M. kawanami;F. Matsunaga;Y. Ishino
激烈火球菌是一种极端嗜热菌，具有真核MCM（微型染色体维持）解旋酶和GINS复合物的同源物。MCM和GINS蛋白都是启动真核细胞DNA复制的重要因子。许多复制相关蛋白的生物化学特征已被报道，但尚未证明每个蛋白的同源物也是古细菌细胞中复制所必需的。在这里，我们证明了P. furiosus GINS复合物与P. furiosus MCM相互作用。染色质免疫沉淀试验表明，GINS复合物的检测优先在oriC区域的热球菌染色体DNA在指数生长期，但不是在稳定期。此外，GINS复合物在体外刺激MCM的ATP酶和DNA解旋酶活性。这些结果有力地表明古菌GINS参与了在P. furiosus中DNA复制的起始和延伸过程，如在真核细胞中观察到的。
Pyrococcus furiosus, a hyperthermophilic Archaea, has homologs of the eukaryotic MCM (mini-chromosome maintenance) helicase and GINS complex. The MCM and GINS proteins are both essential factors to initiate DNA replication in eukaryotic cells. Many biochemical characterizations of the replication-related proteins have been reported, but it has not been proved that the homologs of each protein are also essential for replication in archaeal cells. Here, we demonstrated that the P. furiosus GINS complex interacts with P. furiosus MCM. A chromatin immunoprecipitation assay revealed that the GINS complex is detected preferentially at the oriC region on Pyrococcus chromosomal DNA during the exponential growth phase but not in the stationary phase. Furthermore, the GINS complex stimulates both the ATPase and DNA helicase activities of MCM in vitro. These results strongly suggest that the archaeal GINS is involved in both the initiation and elongation processes of DNA replication in P. furiosus, as observed in eukaryotic cells.