EFFECTS OF MINOR-GROOVE BINDING-DRUGS ON THE INTERACTION OF TATA BOX-BINDING PROTEIN AND TFIIA WITH DNA
EFFECTS OF MINOR-GROOVE BINDING-DRUGS ON THE INTERACTION OF TATA BOX-BINDING PROTEIN AND TFIIA WITH DNA
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DOI：
10.1021/bi00189a003
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发表时间：
1994-06-14
期刊：
影响因子：
2.9
通讯作者：
BEERMAN, TA
中科院分区：
文献类型：
--
作者：
CHIANG, SY;WELCH, J;BEERMAN, TA
TBP（TATA盒结合蛋白），一种通过RNA聚合酶II正确启动基因表达所需的通用转录因子，和小沟结合药物（MGB）都在AT位点与小沟内的DNA相互作用。本研究通过凝胶迁移率变动分析评估了MGBs作为DNA/TBP复合物形成的抑制剂。我们的研究结果表明，可逆的MGBs（DAPI，偏端霉素A，Hoechst 33258，和netropsin）的DNA/TBP复合物的形成是有效的抑制剂，偏端霉素A是最有效的（0.16 μ M抑制TBP复合物的形成50%）。CC-1065是一种与小沟中的DNA共价结合的药物，其活性甚至比偏端霉素A更强（0.00085 μ M抑制50%的TBP复合物形成）。与防止复合物形成所需的药物浓度相比，需要显著更多的CC-1065（0.009 μ M）来破坏预先形成的DNA/TBP复合物。相比之下，药物添加的顺序对可逆的MGBs破坏DNA/TBP复合物的能力几乎没有影响。在TFIIA（一种增强TBP与DNA结合的因子）存在下，需要更高的药物浓度（分别为偏端霉素A和CC-1065）来破坏DNA/TBP/TFIIA的预形成复合物。与MGB相比，能够通过嵌入与DNA结合的药物通常在阻断TBP复合物形成方面较弱，除了海达霉素，其可以嵌入并不可逆地结合DNA，并且与可逆MGB一样有效。
TBP (TATA box binding protein), a general transcription factor required for proper initiation of gene expression by RNA polymerase II, and minor groove binding drugs (MGBs) both interact with DNA within the minor groove at AT sites. This study has evaluated MGBs as inhibitors of DNA/TBP complex formation by gel mobility shift assays. Our results demonstrate that reversible MGBs (DAPI, distamycin A, Hoechst 33258, and netropsin) are effective inhibitors of the formation of DNA/TBP complex and that distamycin A is the most potent (0.16 mu M inhibits TBP complex formation by 50%). CC-1065, a drug that covalently binds to DNA in the minor groove, is even more active than distamycin A (0.00085 mu M inhibits TBP complex formation by 50%). Significantly more CC-1065 (0.009 mu M) is required to break up preformed DNA/TBP complex compared to the drug concentration needed to prevent complex formation. In comparison, the order of drug addition has little influence on the ability of reversible MGBs to disrupt DNA/TBP complex. In the presence of TFIIA, a factor that enhances TBP association with DNA, greater drug concentrations (distamycin A and CC-1065, respectively) are needed to disrupt a preformed complex of DNA/TBP/TFIIA. In comparison to MGBs, drugs capable of binding to DNA by intercalation are generally weaker at blocking TBP complex formation except for hedamycin, which can intercalate and irreversibly bind to DNA and is as effective as reversible MGBs.