Natural variation for seed dormancy in Arabidopsis is regulated by additive genetic and molecular pathways
Natural variation for seed dormancy in Arabidopsis is regulated by additive genetic and molecular pathways
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DOI：
10.1073/pnas.1000410107
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发表时间：
2010-03-02
影响因子：
11.1
通讯作者：
Koornneef, Maarten
中科院分区：
文献类型：
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作者：
Bentsink, Leonie;Hanson, Johannes;Koornneef, Maarten
萌发的时间大概是在强烈的自然选择下，因为它决定了植物萌发和启动其胚后生活周期的环境条件。为了探讨种子休眠是如何控制的，数量性状基因座（QTL）分析已进行了6个拟南芥重组自交系群体，同时分析它们使用混合模型QTL的方法。重组近交系群体来源于参考种质兰茨贝格直立（Ler）和来自世界不同地区的种质之间的杂交。目前已鉴定出11个发芽延迟（DOG）QTL，其中9个已被近等基因系（NIL）证实。不同DOG基因座之间没有强上位性相互作用，表明它们主要通过不同的遗传途径影响休眠。这一点通过分析五种不同DOG NIL的新收获干种子的转录组得到了证实。所有5个DOG近等基因系与其遗传背景Ler的表达相比显示出可辨别的和不同的表达模式。在不同的DOG近等离子体中鉴定的基因代表了很大程度上不同的基因本体谱。这表明拟南芥种子休眠的自然变异主要是由不同的加性遗传和分子途径控制的，而不是上位性互作，表明有几条独立的途径参与其中。
Timing of germination is presumably under strong natural selection as it determines the environmental conditions in which a plant germinates and initiates its postembryonic life cycle. To investigate how seed dormancy is controlled, quantitative trait loci (QTL) analyses has been performed in six Arabidopsis thaliana recombinant inbred line populations by analyzing them simultaneously using a mixed model QTL approach. The recombinant inbred line populations were derived from crosses between the reference accession Landsberg erecta (Ler) and accessions from different world regions. In total, 11 delay of germination (DOG) QTL have been identified, and nine of them have been confirmed by near isogenic lines (NILs). The absence of strong epistatic interactions between the different DOG loci suggests that they affect dormancy mainly by distinct genetic pathways. This was confirmed by analyzing the transcriptome of freshly harvested dry seeds of five different DOG NILs. All five DOG NILs showed discernible and different expression patterns compared with the expression of their genetic background Ler. The genes identified in the different DOG NILs represent largely different gene ontology profiles. It is proposed that natural variation for seed dormancy in Arabidopsis is mainly controlled by different additive genetic and molecular pathways rather than epistatic interactions, indicating the involvement of several independent pathways.