【摘要】 减数分裂过程中同源染色体配对并进行遗传物质的交换与重组,这是形成遗传多样性的来源和进化的原动力,也是育种的遗传基础。重组起始于程序性DNA双链断裂(DSB),其修复过程可导致染色体交换(CO)。DSB和CO在基因组中并非随机分布,存在重组的热点。植物重组热点分布及其产生机制研究较少,但对育种有很大价值。在植物减数分裂重组途径的不同阶段可对重组热点进行作图,一类方法是通过重组后代分析CO位置,另一类方法是对重组发生时的DNA断点序列进行直接检测。本文结合酵母与动物中的工作对这些技术方法的原理、其对植物重组热点研究的贡献及其局限性进行综述。新的技术路线可提高重组热点的作图效率,对认识和利用植物重组现象具有重要意义。更多还原

【Abstract】 Homologous chromosome pairing,synapsis and genetic recombination are achieved in meiosis. Meiotic recombination is the main source of genetic variation in sexually reproducing organisms because the recombination speeds up adaptation,and lay the foundation for traditional plant breeding. The recombination is initiated by the programmed DNA double-stranded breaks( DSBs) that are processed to form chromosome crossovers( COs).DSBs and COs predominantly occur at discrete genomic loci called recombination hotspots. The knowledge about the distribution of recombination hotspots in plant genome as well as the features associated with these areas is invaluable to breeding,yet still largely unknown. Here,methodologies to profile hotspots at different steps of the meiotic recombination pathway,their contributions to understanding of hotspots and their limitations were reviewed. Novel and high-efficiency approaches will not only facilitate the mapping of plant recombination hotspots,but also provide insights about the formation and the control of these hotspots.更多还原