The mode of inhibitory action by aphidicolin on eukaryotic DNA polymerase alpha.
The mode of inhibitory action by aphidicolin on eukaryotic DNA polymerase alpha.
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阿菲迪霉素对真核 DNA 聚合酶 α 的抑制作用模式。
DOI：
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发表时间：
1979
期刊：
影响因子：
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通讯作者：
S. Ikegami
中科院分区：
文献类型：
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作者：
M. Oguro;C. Suzuki;H. Nagano;Y. Mano;S. Ikegami
研究了阿非迪霉素对海胆囊胚核组分DNA聚合酶α的作用方式。Aphidicolin对DNA聚合酶α的抑制作用与活化DNA无竞争性，而与以活化DNA为模板引物的四种脱氧核苷三磷酸有竞争性。对于只有三个脱氧核苷三磷酸的截短（残留或有限）的DNA合成，aphidicolin抑制残留的合成更强烈的dCTP的情况下，比在没有其他三个脱氧核苷三磷酸。过量的dCTP逆转了抑制作用，但其他三种脱氧核苷三磷酸没有逆转。也就是说，阿非迪霉素通过与Ki值为0.5 μ g/ml的dCTP竞争而不与其他三种脱氧核苷三磷酸竞争来抑制DNA聚合酶α。与活化的DNA掺入的dTMP比与poly（dC）掺入的dGMP或dTMP对阿非迪霉素更敏感。（dG）12-18或聚（dA）。（dT）12-18。对于来自小鼠骨髓瘤MOPC 104 E的DNA聚合酶α（B型）获得了类似的结果。
The mode of action by aphidicolin on DNA polymerase alpha from the nuclear fraction of sea-urchin blastulae was studied. The inhibition of DNA polymerase alpha by aphidicolin was uncompetive with activated DNA and competitive with the four deoxynucleoside triphosphates using activated DNA as a template-primer. For truncated (residual or limited) DNA synthesis with only three deoxynucleoside triphosphates, aphidicolin inhibited the residual synthesis more strongly in the absence of dCTP than in the absence of each of the other three deoxynucleoside triphosphates. The inhibition was reversed with excess dCTP but not with the other three deoxynucleoside triphosphates. That is, aphidicolin inhibited DNA polymerase alpha by competing with dCTP with a Ki value of 0.5 microgram/ml and by not competing with the other three deoxynucleoside triphosphates. dTMP incorporation with the activated DNA was more sensitive to aphidicolin than dGMP or dTMP incorporation with poly(dC). (dG)12-18 or poly(dA) . (dT)12-18. Similar results were obtained for DNA polymerase alpha (B form) from mouse myeloma MOPC 104E.