Abstract:
Aliphatic glucosinolates are an abundant group of plant secondary metabolites in Brassica vegetables, with some of their degradation products demonstrating significant anti-cancer effects. The transcription factors MYB28 and MYB29 play key roles in the transcriptional regulation of aliphatic glucosinolates biosynthesis, but little is known about whether BoMYB28 and BoMYB29 are also modulated by upstream regulators or how, nor their gene regulatory networks. In this study, we first explored the hierarchical transcriptional regulatory networks of MYB28 and MYB29 in a model plant, then systemically screened the regulators of the three BoMYB28 homologs in cabbage using a yeast one-hybrid. Furthermore, we selected a novel RNA binding protein, BoRHON1, to functionally validate its roles in modulating aliphatic glucosinolates biosynthesis. Importantly, BoRHON1 induced the accumulation of all detectable aliphatic and indolic glucosinolates, and the net photosynthetic rates of BoRHON1 overexpression lines were significantly increased. Interestingly, the growth and biomass of these overexpression lines of BoRHON1 remained the same as those of the control plants. BoRHON1 was shown to be a novel, potent, positive regulator of glucosinolates biosynthesis, as well as a novel regulator of normal plant growth and development, while significantly increasing plants\' defense costs.
摘要:
脂肪族芥子油苷是芸苔属蔬菜中丰富的一组植物次生代谢产物,它们的一些降解产物表现出显著的抗癌作用。转录因子MYB28和MYB29在脂肪族芥子油苷生物合成的转录调控中起关键作用,但很少有人知道BoMYB28和BoMYB29是否也被上游监管机构调节,也不是他们的基因调控网络。在这项研究中,我们首先在模型植物中探索了MYB28和MYB29的分级转录调控网络,然后使用酵母单杂种系统地筛选了白菜中三个BoMYB28同源物的调节因子。此外,我们选择了一种新的RNA结合蛋白,BoRHON1,在功能上验证其在调节脂肪族芥子油苷生物合成中的作用。重要的是,BoRHON1诱导所有可检测的脂肪族和吲哚芥子油苷的积累,BoRHON1过表达系的净光合速率显著提高。有趣的是,BoRHON1的这些过表达系的生长和生物量保持与对照植物相同。BoRHON1被证明是一部小说,强力,芥子油苷生物合成的正调节剂,以及植物正常生长和发育的新型调节剂,同时显著增加了工厂的国防成本。