Distribution of genes, recombination, and repetitive elements in the maize genome
Distribution of genes, recombination, and repetitive elements in the maize genome
复制标题
DOI：
10.2135/cropsci2006.11.0748tpg
复制
发表时间：
2007-07-01
期刊：
影响因子：
2.3
通讯作者：
Rafalski, Antoni
中科院分区：
文献类型：
--
作者：
Fengler, Kevin;Allen, Stephen M.;Rafalski, Antoni
玉米（Zea mays U）的高密度遗传图谱与由两个自交系 B73 和 Mo17 编译的高分辨率细菌人工染色体 (BAC) 重叠群 mop 集成，用于确定沿染色体的基因密度和重组频率，并比较这些特征作为物理距离函数的分布。重组频率与每个染色体的基因密度密切相关 (r= 0.767-0.960），尽管在着丝粒区域，重组比与基因密度的严格相关性所表明的要低得多。此外，还检查了主要逆转录转座子类别以及 Mu 和 Helitron 插入位点的分布。尽管不同类别的反转录转座子显示，所有玉米染色体上的总体反转录转座子密度相同（r = 0.996） 优先插入不同的染色体区域。 Cinful、Zeon 和 Prem 在着丝粒附近更常见，而 Opie、A 和 Huck 优先位于染色体的亚端粒片段。格兰德并没有表现出相对于染色体上的物理位置的分布偏好。玉米自交系 B73 与普通玉米自交系基因 overgo 探针杂交阳性 BAC 的分布比较 近交 Mo17 表明非岸基因片段（其中许多对应于 Helitron 元件携带的假基因）在着丝粒区域中往往不太常见。正如之前报道的，Mu 转座子似乎优先插入基因附近，如它们在着丝粒区域中的缺乏以及与基因密度的中等相关性（r = 0.759）所示。
A high-density genetic map of maize (Zea mays U, integrated with a high-resolution bacterial artificial chromosome (BAC) contig mop compiled from two inbred lines, B73 and Mo17, was used to determine gene density and recombination frequency along chromosomes and to compare the distribution of these features as a function of physical distance. Recombination frequency is well correlated with gene density for each chromosome (r= 0.767-0.960), although in centromeric regions, recombination is more depressed than a strict correlation with gene density would indicate. In addition, the distribution of major retrotransposon classes and of Mu and Helitron insertion sites were examined . Overall retrotransposon density is equal at all maize chromosomes (r = 0.996), although different classes of retrotransposons display preferential insertion into different chromosome regions. Cinful, Zeon, and Prem are more common near the centromere, while Opie, A and Huck preferentially reside at the subtelomeric segments of chromosomes. Grande does not show preference in distribution relative to physical location on the chromosome. Comparison of the distribution of genic overgo probe hybridization-positive BACs from maize inbred line B73 to those of the inbred Mo17 indicates that nonshored genic segments, many of which correspond to pseudogenes carried by the Helitron elements, tend to be less common in the centromeric region. As previously reported, Mu transposons seem to preferentially insert in the vicinity of genes, as indicated by their paucity in centromeric regions, and moderate correlation (r= 0.759) with gene density.