The qSD12 locus controls offspring tissue-imposed seed dormancy in rice
The qSD12 locus controls offspring tissue-imposed seed dormancy in rice
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DOI：
10.1534/genetics.108.092007
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发表时间：
2008-08-01
期刊：
影响因子：
3.3
通讯作者：
Foley, Michael E.
中科院分区：
文献类型：
--
作者：
Gu, Xing-You;Turnipseed, E. Brent;Foley, Michael E.
利用分子标记辅助遗传方法，将种子成分结构分为母体组织和子代组织(胚乳和胚乳)，以确定具有组织特异性功能的休眠数量性状基因座(QTL)。该方法是为了测试与QTL紧密连锁的标记在萌发和未终止的亚群中的基因/等位基因频率是否偏离孟德尔的预期，该亚群来自部分后熟种子的分离群体，并应用于水稻近等基因背景中的休眠QTL qSD12和qSD7-1。实验结果明确地证明了qSD12在子代组织中的功能(S)，并表明qSD7-1可能通过母体组织控制休眠。这些实验还提供了第一个确凿的证据，证明了后代组织施加的休眠基因导致了由部分后熟种子形成的作图群体的分离扭曲，并在一定程度上导致了杂交植物种子的发芽异质性。后代和母体组织施加的休眠基因分别在生命周期的非常早期和晚期表达，并相互作用，为物种提供互补的适应策略。为了便于克隆和分子标记辅助选择主要休眠基因，在高分辨率图谱上将qSD12基因座缩小到接近600kbp的范围。
Seed component structures were grouped into maternal and offspring (embryo and endosperm) tissues to characterize a dormancy quantitative trait locus (QTL) for tissue-specific function using a marker-assisted genetic approach. The approach was devised to test if genotypic/allelic frequencies of a marker tightly linked to the QTL deviate from Mendelian expectations in germinated and nongerminated subpopulations derived from a segregation population of partially after-ripened seeds and was applied to the dormancy QTL qSD12 and qSD7-1 in a nearly isogenic background of rice. Experimental results unambiguously demonstrated that qSD12 functions in the offspring tissue(s) and suggested that qSD7-1 may control dormancy through the maternal tissues. These experiments also provide the first solid evidence that an offspring tissue-imposed dormancy gene contributes to the segregation distortion in a mapping population developed from partially after-ripened seeds and, in part, to the germination heterogeneity of seeds from hybrid plants. Offspring and maternal tissue-imposed dormancy genes express in very early and late stages of the life cycle, respectively, and interact to provide the species with complementary adaptation strategies. The qSD12 locus was narrowed to the region of similar to 600 kbp on high-resolution map to facilitate cloning and marker-assisted selection of the major dormancy gene.