Biet E, Sun J, Dutreix M
Institut Curie, Section de Recherche UMR144-CNRS, 26 rue d'Ulm, F-75248-Paris Cedex 05, France.
Nucleic Acids Res. 1999 Jan 15;27(2):596-600. doi: 10.1093/nar/27.2.596.
Repetitive sequences have been proposed to be recombinogenic elements in eukaryotic chromosomes. We tested whether dinucleotide repeats sequences are preferential sites for recombination because of their high affinity for recombination enzymes. We compared the kinetics of the binding of the scRad51, hsRad51 and ecRecA proteins to oligonucleotides with repeats of dinucleotides GT, CA, CT, GA, GC or AT. Since secondary structures in single-stranded DNA (ssDNA) act as a barrier to complete binding we measured whether these oligonucleotides are able to form stable secondary structures. We show that the preferential binding of recombination proteins is conserved among the three proteins and is influenced mainly by secondary structures in ssDNA.
重复序列被认为是真核染色体中的重组元件。我们测试了二核苷酸重复序列是否因其对重组酶的高亲和力而成为重组的优先位点。我们比较了scRad51、hsRad51和ecRecA蛋白与含有二核苷酸GT、CA、CT、GA、GC或AT重复序列的寡核苷酸结合的动力学。由于单链DNA（ssDNA）中的二级结构会阻碍完全结合，我们测量了这些寡核苷酸是否能够形成稳定的二级结构。我们发现，这三种蛋白对重组蛋白的优先结合是保守的，并且主要受ssDNA中二级结构的影响。
