Regulation of dormancy in barley by blue light and after-ripening: Effects on abscisic acid and gibberellin metabolism
Regulation of dormancy in barley by blue light and after-ripening: Effects on abscisic acid and gibberellin metabolism
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DOI：
10.1104/pp.107.115469
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发表时间：
2008-06-01
期刊：
影响因子：
7.4
通讯作者：
Jacobsen, John
中科院分区：
文献类型：
--
作者：
Gubler, Frank;Hughes, Trijntje;Jacobsen, John
白色光强烈地促进新鲜收获的谷物的休眠，而黑暗和后熟具有相反的效果。研究了光照和后熟处理对大麦阿坝和GA代谢基因及休眠性的影响。对吸胀大麦籽粒中基因表达的分析表明，不同的阿坝代谢基因被白色光和后熟所靶向。在检测的基因中，白色光促进胚胎中阿坝生物合成基因HvNCED 1的表达。与此结果相一致，酶联免疫吸附测定表明，在白色光下吸胀的休眠谷物比在黑暗中吸胀的谷物具有更高的胚阿坝含量。后熟对阿坝生物合成基因的表达没有影响，但在吸胀后促进阿坝催化基因（HvABA 8 ′ OH 1）、GA生物合成基因（HvGA 3ox 2）和GA分解代谢基因（HvGA 2ox 3）的表达。蓝光模拟了白色光对发芽、阿坝水平以及GA和阿坝代谢基因表达的影响。红光和远红光对发芽、阿坝水平或HvNCED1没有影响。转基因大麦中的RNA干扰实验支持HvABA 8 'OH 1在休眠解除中的作用。与非转基因谷粒相比，转基因HvABA 8 ' OH1 RNAi谷粒中HvABA 8' OH1表达的减少导致阿坝水平更高和休眠增加。
White light strongly promotes dormancy in freshly harvested cereal grains, whereas dark and after-ripening have the opposite effect. We have analyzed the interaction of light and after-ripening on abscisic acid (ABA) and gibberellin (GA) metabolism genes and dormancy in barley ( Hordeum vulgare 'Betzes'). Analysis of gene expression in imbibed barley grains shows that different ABA metabolism genes are targeted by white light and after-ripening. Of the genes examined, white light promotes the expression of an ABA biosynthetic gene, HvNCED1, in embryos. Consistent with this result, enzyme-linked immunosorbent assays show that dormant grains imbibed under white light have higher embryo ABA content than grains imbibed in the dark. After-ripening has no effect on expression of ABA biosynthesis genes, but promotes expression of an ABA catabolism gene ( HvABA8' OH1), a GA biosynthetic gene ( HvGA3ox2), and a GA catabolic gene ( HvGA2ox3) following imbibition. Blue light mimics the effects of white light on germination, ABA levels, and expression of GA and ABA metabolism genes. Red and far-red light have no effect on germination, ABA levels, or HvNCED1. RNA interference experiments in transgenic barley plants support a role of HvABA8' OH1 in dormancy release. Reduced HvABA8' OH1 expression in transgenic HvABA8' OH1 RNAi grains results in higher levels of ABA and increased dormancy compared to nontransgenic grains.