Molinier Jean, Ries Gerhard, Bonhoeffer Sebastian, Hohn Barbara
Friedrich Miescher Institute, CH-4058 Basel, Switzerland.
Plant Cell. 2004 Feb;16(2):342-52. doi: 10.1105/tpc.019042. Epub 2004 Jan 16.
Intermolecular recombination events were monitored in Arabidopsis thaliana lines using specially designed recombination traps consisting of tandem disrupted beta-glucuronidase or luciferase reporter genes in direct repeat orientation. Recombination frequencies (RFs) varied between the different lines, indicating possible position effects influencing intermolecular recombination processes. The RFs between sister chromatids and between homologous chromosomes were measured in plants either hemizygous or homozygous for a transgene locus. The RFs in homozygous plants exceeded those of hemizygous plants by a factor of >2, implying that in somatic plant cells both sister chromatid recombination and recombination between homologous chromosomes exist for recombinational DNA repair. In addition, different DNA-damaging agents stimulated recombination in homozygous and hemizygous plants to different extents in a manner dependent on the type of DNA damage and on the genomic region. The genetic and molecular analysis of recombination events showed that most of the somatic recombination events result from gene conversion, although a pop-out event has also been characterized.
利用特别设计的重组陷阱监测拟南芥品系中的分子间重组事件，该陷阱由以直接重复方向排列的串联破坏的β-葡萄糖醛酸酶或荧光素酶报告基因组成。不同品系间的重组频率（RFs）有所不同，表明可能存在影响分子间重组过程的位置效应。在转基因位点半合子或纯合子的植物中测量姐妹染色单体之间以及同源染色体之间的RFs。纯合植物中的RFs比半合子植物高出>2倍，这意味着在体细胞植物细胞中，姐妹染色单体重组和同源染色体之间的重组都存在于重组性DNA修复中。此外，不同的DNA损伤剂以依赖于DNA损伤类型和基因组区域的方式，在不同程度上刺激纯合和半合子植物中的重组。重组事件的遗传和分子分析表明，大多数体细胞重组事件是由基因转换引起的，尽管也鉴定出了一个弹出事件。
