文献类型： 外文期刊

作者： Li, Dongxiao ¹ ; Ye, Guangying ² ; Li, Jie ¹ ; Lai, Zhenqin ¹ ; Ruan, Siyou ¹ ; Qi, Qi ¹ ; Wang, Zaihua ² ; Duan, Sujuan ¹ ; Jin, Hong-Lei ¹ ; Wang, Hong-Bin ¹ ;

作者机构： 1.Guangzhou Univ Chinese Med, Inst Med Plant Physiol & Ecol, Sch Pharmaceut Sci, Guangzhou 510006, Peoples R China

2.Guangdong Acad Agr Sci, Environm Hort Res Inst, Guangdong Prov Key Lab Ornamental Plant Germplasm, Guangzhou 510640, Peoples R China

3.Guangzhou Univ Chinese Med, Guangzhou Key Lab Chinese Med Res Prevent & Treatm, Affiliated Hosp 3, Guangzhou 510375, Peoples R China

4.Guangzhou Univ Chinese Med, Key Lab Chinese Med Resource Lingnan, Minist Educ, Guangzhou 510006, Peoples R China

关键词： Dendrobium officinale; high light; flavonoid; polysaccharide; quality formation; metabolome; transcriptome

期刊名称：PLANT JOURNAL （ 影响因子：7.2； 五年影响因子：7.9 ）

ISSN： 0960-7412

年卷期： 2023 年 115 卷 4 期

页码：

收录情况： SCI

摘要： Dendrobium officinale is edible and has medicinal and ornamental functions. Polysaccharides and flavonoids, including anthocyanins, are important components of D. officinale that largely determine the nutritional quality and consumer appeal. There is a need to study the molecular mechanisms regulating anthocyanin and polysaccharide biosynthesis to enhance D. officinale quality and its market value. Here, we report that high light (HL) induced the accumulation of polysaccharides, particularly mannose, as well as anthocyanin accumulation, resulting in red stems. Metabolome and transcriptome analyses revealed that most of the flavonoids showed large changes in abundance, and flavonoid and polysaccharide biosynthesis was significantly activated under HL treatment. Interestingly, DoHY5 expression was also highly induced. Biochemical analyses demonstrated that DoHY5 directly binds to the promoters of DoF3H1 (involved in anthocyanin biosynthesis), DoGMPP2, and DoPMT28 (involved in polysaccharide biosynthesis) to activate their expression, thereby promoting anthocyanin and polysaccharide accumulation in D. officinale stems. DoHY5 silencing decreased flavonoid- and polysaccharide-related gene expression and reduced anthocyanin and polysaccharide accumulation, whereas DoHY5 overexpression had the opposite effects. Notably, naturally occurring red-stemmed D. officinale plants similarly have high levels of anthocyanin and polysaccharide accumulation and biosynthesis gene expression. Our results reveal a previously undiscovered role of DoHY5 in co-regulating anthocyanin and polysaccharide biosynthesis under HL conditions, improving our understanding of the mechanisms regulating stem color and determining nutritional quality in D. officinale. Collectively, our results propose a robust and simple strategy for significantly increasing anthocyanin and polysaccharide levels and subsequently improving the nutritional quality of D. officinale.