Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Agricultural College of Yangzhou University, Yangzhou 225009, China.
Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Agricultural College of Yangzhou University, Yangzhou 225009, China; Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China.
Plant Sci. 2019 Sep;286:17-27. doi: 10.1016/j.plantsci.2019.03.008. Epub 2019 Mar 26.
The plant-specific gibberellic acid (GA)-stimulated transcript gene family is critical for plant growth and development. There are 10 family members in rice (Oryza sativa), known as OsGASRs. However, few have been functionally characterized. Here, we investigated the function of OsGASR9 in rice. OsGASR9 transcripts were detected in various tissues, with the lowest and highest levels in leaves and panicles, respectively. Greater mRNA levels accumulated in young, compared with in old, panicles and spikelets. OsGASR9 localized to the plasma membrane, cytoplasm and nucleus. Transgenic RNA interference-derived lines in the Zhonghua 11 background exhibited reduced plant height, grain size and yield compared with the wild-type. The two osgasr9 mutants in the Nipponbare background showed similar phenotypes. Conversely, the overexpression of OsGASR9 in the two backgrounds increased plant height and grain size. A significantly increased grain yield per plant was also observed in the overexpression lines having a Nipponbare background. Furthermore, by measuring the GA-induced lengths of the second leaf sheaths and α-amylase activity levels of seeds, we concluded that OsGASR9 is a positive regulator of responses to GA in rice. Thus, OsGASR9 may regulate plant height, grain size and yield through the GA pathway and could have an application value in breeding.
植物特有的赤霉素（GA）刺激转录基因家族对于植物的生长和发育至关重要。在水稻（Oryza sativa）中有 10 个家族成员，被称为 OsGASRs。然而，它们的功能特征很少被研究。在这里，我们研究了水稻中 OsGASR9 的功能。OsGASR9 的转录本在各种组织中均有检测到，在叶片和穗中分别具有最低和最高的水平。在年轻的穗和小穗中，mRNA 水平积累得更多，而在老的穗和小穗中则更少。OsGASR9 定位于质膜、细胞质和细胞核。在 Zhonghua 11 背景下的转基因 RNA 干扰衍生系与野生型相比，表现出植株高度、粒型和产量降低。在 Nipponbare 背景下的两个 osgasr9 突变体表现出相似的表型。相反，在这两个背景下过表达 OsGASR9 增加了植株高度和粒型。在具有 Nipponbare 背景的过表达系中也观察到每株产量显著增加。此外，通过测量 GA 诱导的第二叶鞘长度和种子中α-淀粉酶活性水平，我们得出结论，OsGASR9 是水稻中对 GA 反应的正调节剂。因此，OsGASR9 可能通过 GA 途径调节株高、粒型和产量，并在育种中有应用价值。
