Polyamine-induced Z-DNA conformation in plasmids containing (dA-dC)n.(dG-dT)n inserts and increased binding of lupus autoantibodies to the Z-DNA form of plasmids.
Polyamine-induced Z-DNA conformation in plasmids containing (dA-dC)n.(dG-dT)n inserts and increased binding of lupus autoantibodies to the Z-DNA form of plasmids.
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含有 (dA-dC)n.(dG-dT)n 插入片段的质粒中多胺诱导 Z-DNA 构象，并增加狼疮自身抗体与质粒 Z-DNA 形式的结合。
DOI：
10.1042/bj2980485
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
Thomas,T
中科院分区：
文献类型：
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作者：
Thomas,TJ;Thomas,T
潜在的z - dna形成（dA-dC）阻滞n。（dG-dT）n序列在真核生物基因组中普遍存在。我们检测了天然存在的多胺，腐胺，亚精胺和精胺，是否可以在pDHf2和pDHf14质粒中分别插入23和60 bp的（dA-dC）n，从而引起Z-DNA构象。亚精胺和精胺能激发这些质粒中的Z-DNA构象，但腐胺不起作用。对于pDHf2和pDHf14， B-DNA向Z-DNA过渡中点的亚精胺浓度为25微米，精胺浓度为16微米。亚精胺同源物诱导Z-DNA的能力具有明显的多胺结构特异性。无机阳离子Co(NH3)6（3+）和Ru(NH3)6（3+）无效。我们的实验还显示，在多胺存在的情况下，狼疮患者和自身免疫MRL-lpr/lpr小鼠的抗dna自身抗体与pDHf2和pDHf14的结合增加。这些数据表明（dA-dC）n的小块。（dG-dT）n序列在天然多胺存在下呈现Z-DNA构象。狼疮患者血清中多胺浓度的增加可能促进循环DNA和抗z -DNA抗体的免疫复合物的形成。
Blocks of potential Z-DNA-forming (dA-dC)n.(dG-dT)n sequences are ubiquitous in eukaryotic genomes. We examined whether naturally occurring polyamines, putrescine, spermidine and spermine, could provoke the Z-DNA conformation in plasmids pDHf2 and pDHf14 with 23 and 60 bp inserts respectively of (dA-dC)n.(dG-dT)n sequences using an e.l.i.s.a. Spermidine and spermine could provoke Z-DNA conformation in these plasmids, but putrescine was ineffective. For pDHf2 and pDHf14, the concentration of spermidine at the midpoint of B-DNA to Z-DNA transition was 25 microM, whereas that of spermine was 16 microM. Polyamine structural specificity was evident in the ability of spermidine homologues to induce Z-DNA. Inorganic cations, Co(NH3)6(3+) and Ru(NH3)6(3+), were ineffective. Our experiments also showed increased binding of anti-DNA autoantibodies from lupus patients as well as autoimmune MRL-lpr/lpr mice to pDHf2 and pDHf14 in the presence of polyamines. These data demonstrate that small blocks of (dA-dC)n.(dG-dT)n sequences could assume the Z-DNA conformation in the presence of natural polyamines. Increased concentrations of polyamines in the sera of lupus patients might facilitate immune complex-formation involving circulating DNA and anti-Z-DNA antibodies.