The contribution of recombination to heterozygosity differs among plant evolutionary lineages and life-forms.
The contribution of recombination to heterozygosity differs among plant evolutionary lineages and life-forms.
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DOI：
10.1186/1471-2148-10-22
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发表时间：
2010-01-25
影响因子：
3.4
通讯作者：
González-Martínez SC
中科院分区：
文献类型：
--
作者：
Jaramillo-Correa JP;Verdú M;González-Martínez SC
尽管它作为单倍型变异的产生者发挥着作用，但我们对跨类群的重组率如何演变知之甚少。重组是一种非常不稳定的力量，容易受到进化和生命特征相关过程的影响，这些过程也与遗传多样性的一般水平相关。例如，在植物中，研究表明，长寿的异交类群（例如树木）在 SSR 和同种异型酶方面比自交或一年生物种具有更高的杂合度 (He)。然而，其中一些树类群在 DNA 序列水平上的核苷酸多样性水平低得惊人，这表明重组是这些生物体中遗传多样性的潜在产生者。在这项研究中，我们研究了植物类群中全基因组和基因内的重组率如何演变，确定这些比率是否受到物种采用的生命形式的影响，并评估较高的全基因组重组率是否会转化为较高的 He 值，尤其是在树木中。对 81 种高等植物的全基因组 (cM/Mb) 重组率的估计显示出显着的系统发育信号。使用不同的比较系统发育模型表明，重组率与He之间存在正相关（0.83±0.29），并且树木比短命草本和灌木具有更高的全基因组重组率。我们的模型进一步证明了一个重要的分类成分，因为针叶树的重组率低于被子植物。在基因内水平也发现了这种趋势。总而言之，我们的结果说明了如何必须考虑共同祖先和生活史特征，以了解植物物种遗传多样性和基因组重组率的进化，并强调物种生命形式的相关性以解释多样性和重组的一般水平。
Despite its role as a generator of haplotypic variation, little is known about how the rates of recombination evolve across taxa. Recombination is a very labile force, susceptible to evolutionary and life trait related processes, which have also been correlated with general levels of genetic diversity. For example, in plants, it has been shown that long-lived outcrossing taxa, such as trees, have higher heterozygosity (He) at SSRs and allozymes than selfing or annual species. However, some of these tree taxa have surprisingly low levels of nucleotide diversity at the DNA sequence level, which points to recombination as a potential generator of genetic diversity in these organisms. In this study, we examine how genome-wide and within-gene rates of recombination evolve across plant taxa, determine whether such rates are influenced by the life-form adopted by species, and evaluate if higher genome-wide rates of recombination translate into higher He values, especially in trees. Estimates of genome-wide (cM/Mb) recombination rates from 81 higher plants showed a significant phylogenetic signal. The use of different comparative phylogenetic models demonstrated that there is a positive correlation between recombination rate and He (0.83 ± 0.29), and that trees have higher rates of genome-wide recombination than short-lived herbs and shrubs. A significant taxonomic component was further made evident by our models, as conifers exhibited lower recombination rates than angiosperms. This trend was also found at the within-gene level. Altogether, our results illustrate how both common ancestry and life-history traits have to be taken into account for understanding the evolution of genetic diversity and genomic rates of recombination across plant species, and highlight the relevance of species life forms to explain general levels of diversity and recombination.
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影响因子：
7
作者：
Jensen-Seaman, MI;Furey, TS;Jacob, HJ
通讯作者：
Jacob, HJ
影响因子：
2.2
作者：
Hamrick, J. L.;Godt, Mary Jo W.;Sherman-Broyles, Susan L.
通讯作者：
Sherman-Broyles, Susan L.
DOI：
10.1073/pnas.0307937101
发表时间：
2004-06-29
影响因子：
11.1
作者：
Dirlewanger, E;Graziano, E;Arús, P
通讯作者：
Arús, P
影响因子：
3.3
作者：
LYNCH, M;HILL, WG
通讯作者：
HILL, WG
影响因子：
3
作者：
Bouillé, M;Bousquet, J
通讯作者：
Bousquet, J