Melamed-Bessudo Cathy, Yehuda Elizabeth, Stuitje Antoine R, Levy Avraham A
Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel.
Plant J. 2005 Aug;43(3):458-66. doi: 10.1111/j.1365-313X.2005.02466.x.
Meiotic recombination is a fundamental biological process that plays a central role in the evolution and breeding of plants. We have developed a new seed-based assay for meiotic recombination in Arabidopsis. The assay is based on the transformation of green and red fluorescent markers expressed under a seed-specific promoter. A total of 74 T-DNA markers were isolated, sequenced and mapped both physically and genetically. Lines containing red and green markers that map 1-20 cM apart were crossed to produce tester lines with the two markers linked in cis yielding seeds that fluoresced both in red and green. We show that these lines can be used for efficient scoring of recombinant types (red only or green only fluorescing seeds) in a seed population derived from a test cross (backcross) or self-pollination. Two tester lines that were characterized during several generations of backcross and self-pollination, one in the background of ecotype Landsberg and one in the ecotype Columbia, are described. We discuss the number of plants and seeds to be scored in order to obtain reliable and reproducible crossing over rate values. This assay offers a relatively high-throughput method, with the benefit of seed markers (similar to the maize classical genetic markers) combined with the advantages of Arabidopsis. It advances the prospect to better understand the factors that affect the rate of meiotic crossover in plants and to stimulate this process for more efficient breeding and mapping.
减数分裂重组是一个基本的生物学过程，在植物的进化和育种中起着核心作用。我们开发了一种用于拟南芥减数分裂重组的基于种子的新检测方法。该检测方法基于在种子特异性启动子控制下表达的绿色和红色荧光标记的转化。总共分离、测序了74个T-DNA标记，并进行了物理和遗传定位。将含有相距1-20厘摩的红色和绿色标记的株系杂交，以产生两个标记顺式连锁的测试株系，从而产生红色和绿色都发荧光的种子。我们表明，这些株系可用于在测交（回交）或自花授粉产生的种子群体中对重组类型（仅红色或仅绿色发荧光的种子）进行有效评分。描述了在几代回交和自花授粉过程中表征的两个测试株系，一个是生态型兰茨贝格背景，另一个是生态型哥伦比亚背景。我们讨论了为获得可靠且可重复的交换率值而需要评分的植株和种子数量。该检测方法提供了一种相对高通量的方法，兼具种子标记（类似于玉米经典遗传标记）的优点和拟南芥的优势。它推进了更好地理解影响植物减数分裂交叉率的因素以及刺激这一过程以实现更高效育种和定位的前景。
