Molecular Analysis of Meiotic Recombination in Maize

利用大量青铜（bz）基因缺陷突变体，将进一步研究玉米减数分裂重组过程。该基因影响种子的色素沉着，其重组性至少是玉米中普通DNA片段的100倍，因此可以产生许多基因内重组以供分析。对玉米减数分裂重组过程的研究将包括：1)确定在恒定遗传背景下bz区域转化束的连续性和平均长度；2)确定bz基因外的遗传距离和物理距离之间的关系，将其与侧翼DNA的重复性和独特性相关联，并将其与bz基因座内部已经确定的关系进行比较。3)细化bz内遗传距离和物理距离之间的关系；4)进一步分析插入对基因内和基因间重组的抑制作用，确定单碱基对异源对重组的影响程度；5)检验玉米重组过程的保真度。减数分裂重组是一种基本的遗传过程，可以在有性生殖的生物体中产生新的基因型。然而，尽管它的重要性，很少有工作已经做了阐明植物减数分裂重组的过程。这项工作将对这一领域的知识宝库作出重要贡献。＊＊＊

9630358 Dooner The meiotic recombination process in maize will be further investigated with the use of the large collection of mutants which have a defect in the bronze (bz) gene. That gene affects seed pigmentation and is at least 100 times more recombinogenic than the average DNA segment in maize, so that many intragenic recombinants can be generated for analysis. The meiotic recombination process in maize will be investigated by 1) determining the continuity and average length of conversion tracts for the bz region in a constant genetic background, 2) determining the relationship between genetic and physical distance outside of the bz gene, correlating it with the repetitive vs. the unique nature of the flanking DNA and comparing it with the relationship already determined inside of the bz locus, 3) refining the relationship between genetic and physical distance within bz, 4) further analyzing the suppressing effect of insertions on intragenic as well as intergenic, recombination and determine the extant to which single base pair heterologies affect recombination and 5) examining the fidelity of the recombination process in maize. %%% Meiotic recombination is a fundamental genetic process and can serve to create novel genotypes in sexually reproducing organisms. Yet, in spite of its importance, little work has been done to elucidate the process of meiotic recombination in plants. This work will make important contributions to that small storehouse of knowledge in this area. ***