The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao 266237, China.
College of Pharmacy, Liaocheng University, Liaocheng 252000, China.
Int J Mol Sci. 2020 Sep 30;21(19):7239. doi: 10.3390/ijms21197239.
UDP-glycosyltransferases (UGTs) play key roles in modulating plant development and responses to environmental challenges. Previous research reported that the Arabidopsis UDP-glucosyltransferase 74E2 (), which transfers glucose to indole-3-butyric acid (IBA), is involved in regulating plant architecture and stress responses. Here, we show novel and distinct roles of in rice. We found that overexpression of in rice could enhance seed germination. This effect was also observed in the presence of IBA and abscisic acid (ABA), as well as salt and drought stresses. Further investigation indicated that the overexpression lines had lower levels of free IBA and ABA compared to wild-type plants. Auxin signaling pathway gene expression such as for and genes, as well as ABA signaling pathway genes and was substantially downregulated in germinating seeds of overexpression lines. Consistently, due to reduced IBA and ABA levels, the established seedlings were less tolerant to drought and salt stresses. The regulation of rice seed germination and stress tolerance could be attributed to IBA and ABA level alterations, as well as modulation of the auxin/ABA signaling pathways by . The distinct roles of in rice implied that complex and different molecular regulation networks exist between Arabidopsis and rice.
UDP-糖基转移酶（UGTs）在调节植物发育和应对环境挑战方面发挥着关键作用。先前的研究报道，拟南芥 UDP-葡萄糖基转移酶 74E2（），它将葡萄糖转移到吲哚-3-丁酸（IBA）中，参与调节植物的结构和应激反应。在这里，我们展示了在水稻中的新的和独特的作用。我们发现，在水稻中超表达可以增强种子萌发。这种效应也在存在 IBA 和脱落酸（ABA）以及盐和干旱胁迫时观察到。进一步的研究表明，与野生型植物相比，过表达系的游离 IBA 和 ABA 水平较低。在萌发种子中，生长素信号通路基因如和基因以及 ABA 信号通路基因和基因的表达被显著下调。一致地，由于 IBA 和 ABA 水平降低，已建立的幼苗对干旱和盐胁迫的耐受性降低。水稻种子萌发和应激耐受性的调节可以归因于 IBA 和 ABA 水平的改变，以及通过对生长素/ABA 信号通路的调节。在水稻中，的独特作用表明，拟南芥和水稻之间存在复杂和不同的分子调控网络。
