Pearson C E, Zannis-Hadjopoulos M, Price G B, Zorbas H
McGill Cancer Centre, McGill University, Montreal, Quebec, Canada.
EMBO J. 1995 Apr 3;14(7):1571-80. doi: 10.1002/j.1460-2075.1995.tb07143.x.
We recently identified and enriched a protein (CBP) from HeLa cells with binding specificity for cruciform-containing DNA. We have now studied the interaction of CBP with stable cruciform DNA molecules containing the 27 bp palindrome of SV40 on one strand and an unrelated 26 bp palindrome on the other strand by hydroxyl radical footprinting. The CBP-DNA interaction is localized to the four-way junction at the base of the cruciforms. CBP appears to interact with the elbows of the junctions in an asymmetric fashion. Upon CBP binding, structural distortions were observed in the cruciform stems and in a DNA region adjacent to the junction. These features distinguish CBP from other cruciform binding proteins, which bind symmetrically and display exclusively either contacts with the DNA backbone or structural alterations in the DNA.
我们最近从HeLa细胞中鉴定并富集了一种对含十字形DNA具有结合特异性的蛋白质（CBP）。现在，我们通过羟基自由基足迹法研究了CBP与稳定的十字形DNA分子的相互作用，该分子一条链上含有SV40的27bp回文序列，另一条链上含有不相关的26bp回文序列。CBP与DNA的相互作用定位于十字形底部的四链交汇点。CBP似乎以不对称方式与交汇点的肘部相互作用。CBP结合后，在十字形茎部和与交汇点相邻的DNA区域观察到结构扭曲。这些特征将CBP与其他十字形结合蛋白区分开来，其他蛋白以对称方式结合，并且仅与DNA主链接触或导致DNA结构改变。
