Pearson C E, Zorbas H, Price G B, Zannis-Hadjopoulos M
McGill Cancer Centre, McGill University, Montréal, Quebec, Canada.
J Cell Biochem. 1996 Oct;63(1):1-22. doi: 10.1002/(SICI)1097-4644(199610)63:1%3C1::AID-JCB1%3E3.0.CO;2-3.
Inverted repeats occur nonrandomly in the DNA of most organisms. Stem-loops and cruciforms can form from inverted repeats. Such structures have been detected in pro- and eukaryotes. They may affect the supercoiling degree of the DNA, the positioning of nucleosomes, the formation of other secondary structures of DNA, or directly interact with proteins. Inverted repeats, stem-loops, and cruciforms are present at the replication origins of phage, plasmids, mitochondria, eukaryotic viruses, and mammalian cells. Experiments with anti-cruciform antibodies suggest that formation and stabilization of cruciforms at particular mammalian origins may be associated with initiation of DNA replication. Many proteins have been shown to interact with cruciforms, recognizing features like DNA crossovers, four-way junctions, and curved/bent DNA of specific angles. A human cruciform binding protein (CBP) displays a novel type of interaction with cruciforms and may be linked to initiation of DNA replication.
反向重复序列在大多数生物体的DNA中呈非随机出现。茎环结构和十字形结构可由反向重复序列形成。此类结构已在原核生物和真核生物中被检测到。它们可能会影响DNA的超螺旋程度、核小体的定位、DNA其他二级结构的形成，或直接与蛋白质相互作用。反向重复序列、茎环结构和十字形结构存在于噬菌体、质粒、线粒体、真核病毒及哺乳动物细胞的复制起点处。用抗十字形抗体进行的实验表明，特定哺乳动物复制起点处十字形结构的形成与稳定可能与DNA复制的起始有关。许多蛋白质已被证明可与十字形结构相互作用，识别诸如DNA交叉、四向连接以及特定角度的弯曲/弯折DNA等特征。一种人类十字形结合蛋白（CBP）与十字形结构表现出一种新型的相互作用，并且可能与DNA复制的起始相关联。
