Crystal structure of an antiparallel DNA fragment with Hoogsteen base pairing
Crystal structure of an antiparallel DNA fragment with Hoogsteen base pairing
复制标题
DOI：
10.1073/pnas.052675499
复制
发表时间：
2002-03-05
影响因子：
11.1
通讯作者：
Subirana, JA
中科院分区：
文献类型：
--
作者：
Abrescia, NGA;Thompson, A;Subirana, JA
我们在这里报告的DNA分子的另一种双螺旋结构。通过单晶X射线晶体学在d（ATA（Br）UAT）和d（ATATAT）序列中发现了它。该序列不仅存在于TATA盒中，而且存在于DNA的其他调控区域中。两条反平行链的碱基形成Hoogsteen对，其中腺嘌呤处于顺式构象。这种结构既不与三螺旋中的结构相关，也不与平行的DNA双链体相关。其构象参数与B型双链DNA的构象参数非常相似。这两种形式在生理条件下可以共存，尽管Hoogsteen配对极大地影响了DNA上的识别位点。我们的研究结果表明，一种替代经典的B-DNA双螺旋是可能的。
We report here an alternative double-helical structure of the DNA molecule. It has been found in the d(ATA(Br)UAT) and d(ATATAT) sequences by single-crystal x-ray crystallography. This sequence is found not only in TATA boxes, but also in other regulatory regions of DNA. Bases of the two antiparallel strands form Hoogsteen pairs, with adenines in the syn conformation. The structure is related neither to those found in triple helices nor to parallel DNA duplexes. Its conformational parameters are very similar to those of duplex DNA in the B form. Both forms may coexist under physiological conditions, although the Hoogsteen pairing greatly influences the recognition sites on DNA. Our results demonstrate that an alternative to the classical B-DNA double helix is possible.