Dehydroaltenusin, a mammalian DNA polymerase α inhibitor
Dehydroaltenusin, a mammalian DNA polymerase α inhibitor
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DOI：
10.1074/jbc.m006096200
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发表时间：
2000-10-27
影响因子：
4.8
通讯作者：
Sakaguchi, K
中科院分区：
文献类型：
--
作者：
Mizushina, Y;Kamisuki, S;Sakaguchi, K
发现脱氢阿替努辛在体外是哺乳动物DNA聚合酶α（pol α）的抑制剂。令人惊讶的是，在测试的聚合酶和DNA代谢酶中，脱氢Altenusin仅抑制哺乳动物pol α。脱氢阿替努辛不影响其他复制型DNA聚合酶的活性，如δ和β;它甚至对另一种脊椎动物（鱼）或植物物种的pol α活性也没有影响。脱氢Altenusin对哺乳动物pol α的抑制作用是剂量依赖性的，并且在0.5 μ M的浓度下观察到50%的抑制。脱氢阿替努辛诱导的哺乳动物pol α活性抑制与模板引物竞争，与dNTP底物非竞争。BIAcore分析表明，脱氢Altenusin结合到小鼠pol α的最大亚基p180的核心结构域，其具有催化活性，但不结合到小鼠pol α的最小亚基或DNA引发酶p46。这些结果表明，脱氢Altenusin分子与模板引物分子在其哺乳动物pol α的催化结构域的结合位点上竞争，结合到该位点，并同时干扰dNTP底物掺入到模板引物中。
Dehydroaltenusin was found to be an inhibitor of mammalian DNA polymerase alpha (pol alpha) in vitro. Surprisingly, among the polymerases and DNA metabolic enzymes tested, dehydroaltenusin inhibited only mammalian pol alpha. Dehydroaltenusin did not influence the activities of the other replicative DNA polymerases, such as delta and epsilon; it also showed no effect even on the pol alpha activity from another vertebrate (fish) or plant species. The inhibitory effect of dehydroaltenusin on mammalian pol alpha was dose-dependent, and 50% inhibition was observed at a concentration of 0.5 muM. Dehydroaltenusin-induced inhibition of mammalian pol alpha activity was competitive with the template-primer and non-competitive with the dNTP substrate. BIAcore analysis demonstrated that dehydroaltenusin bound to the core domain of the largest subunit, p180, of mouse pol alpha, which has catalytic activity, but did not bind to the smallest subunit or the DNA primase p46 of mouse pol alpha. These results suggest that the dehydroaltenusin molecule competes with the template primer molecule on its binding site of the catalytic domain of mammalian pol alpha, binds to the site, and simultaneously disturbs dNTP substrate incorporation into the template-primer.