Two Types of Meiotic Crossovers Coexist in Maize
Two Types of Meiotic Crossovers Coexist in Maize
复制标题
DOI：
10.1105/tpc.109.071514
复制
发表时间：
2009-12-01
期刊：
影响因子：
11.6
通讯作者：
Martin, Olivier C.
中科院分区：
文献类型：
--
作者：
Falque, Matthieu;Anderson, Lorinda K.;Martin, Olivier C.
我们应用建模方法来研究玉米（Zea mays）中晚期重组结节的分布。这些结节表明联会复合体沿着的交叉位置。高质量的结核数据进行了分析，使用两种不同的干涉模型：“统计”伽马模型和“机械”束膜模型。对于每条染色体，我们排除了在98%的显着性水平的假设，一个单一的途径形成的所有交换，指出在玉米中共存的两种类型的交换，如以前在其他生物体中所证明的。我们估计来自非干扰途径的交叉比例范围为6%至23%，取决于染色体，细胞平均值为15%。每条染色体的非干扰性交换的平均数与联会复合体的长度显著相关。我们还量化了干扰的强度。最后，我们开发的推理工具，允许一个解决，没有太多的损失的权力，复杂的交叉干扰模型，如beamfilm。由于这种模型缺乏似然函数，因此无法用于参数估计。这一进展将允许更现实的交叉形成机制，在未来建模。
We apply modeling approaches to investigate the distribution of late recombination nodules in maize (Zea mays). Such nodules indicate crossover positions along the synaptonemal complex. High-quality nodule data were analyzed using two different interference models: the "statistical" gamma model and the "mechanical" beam film model. For each chromosome, we exclude at a 98% significance level the hypothesis that a single pathway underlies the formation of all crossovers, pointing to the coexistence of two types of crossing-over in maize, as was previously demonstrated in other organisms. We estimate the proportion of crossovers coming from the noninterfering pathway to range from 6 to 23% depending on the chromosome, with a cell average of similar to 15%. The mean number of noninterfering crossovers per chromosome is significantly correlated with the length of the synaptonemal complex. We also quantify the intensity of interference. Finally, we develop inference tools that allow one to tackle, without much loss of power, complex crossover interference models such as the beamfilm. The lack of a likelihood function in such models had prevented their use for parameter estimation. This advance will allow more realistic mechanisms of crossover formation to be modeled in the future.