Yang Weizong, Hu Jiayuan, Behera Jyoti R, Kilaru Aruna, Yuan Yanping, Zhai Yuhui, Xu Yanfeng, Xie Lihang, Zhang Yanlong, Zhang Qingyu, Niu Lixin
College of Landscape Architecture and Arts, Northwest A&F University, Yangling, China.
Oil Peony Engineering Technology Research Center of National Forestry Administration, Yangling, China.
Front Plant Sci. 2021 Dec 10;12:796181. doi: 10.3389/fpls.2021.796181. eCollection 2021.
In many higher plants, seed oil accumulation is governed by complex multilevel regulatory networks including transcriptional regulation, which primarily affects fatty acid biosynthesis. Tree peony (), a perennial deciduous shrub endemic to China is notable for its seed oil that is abundant in unsaturated fatty acids. We discovered that a tree peony trihelix transcription factor, PrASIL1, localized in the nucleus, is expressed predominantly in developing seeds during maturation. Ectopic overexpression of in leaf tissue and seeds significantly reduced total fatty acids and altered the fatty acid composition. These changes were in turn associated with the decreased expression of multitudinous genes involved in plastidial fatty acid synthesis and oil accumulation. Thus, we inferred that PrASIL1 is a critical transcription factor that represses oil accumulation by down-regulating numerous key genes during seed oil biosynthesis. In contrary, up-regulation of oil biosynthesis genes and a significant increase in total lipids and several major fatty acids were observed in silenced tree peony leaves. Together, these results provide insights into the role of trihelix transcription factor PrASIL1 in controlling seed oil accumulation. can be targeted potentially for oil enhancement in tree peony and other crops through gene manipulation.
在许多高等植物中，种子油的积累受包括转录调控在内的复杂多层次调控网络控制，转录调控主要影响脂肪酸的生物合成。牡丹是中国特有的多年生落叶灌木，其种子油富含不饱和脂肪酸，因而引人注目。我们发现，牡丹三螺旋转录因子PrASIL1定位于细胞核，在种子成熟过程中主要在发育中的种子中表达。在叶片组织和种子中异位过表达PrASIL1显著降低了总脂肪酸含量，并改变了脂肪酸组成。这些变化又与参与质体脂肪酸合成和油脂积累的众多基因表达降低有关。因此，我们推断PrASIL1是一个关键转录因子，在种子油生物合成过程中通过下调众多关键基因来抑制油脂积累。相反，在沉默的牡丹叶片中观察到油脂生物合成基因上调，总脂质和几种主要脂肪酸显著增加。这些结果共同为三螺旋转录因子PrASIL1在控制种子油积累中的作用提供了见解。通过基因操作，PrASIL1有可能成为提高牡丹和其他作物油脂含量的靶点。
