苦参草（L.)Moq。,众所周知的沙米，是沙区重要的野生牧草，是有前途的食用和药用资源植物，具有很大的驯化潜力。以前的研究表明，黄酮类化合物是沙米中最丰富的药用成分之一，其中异鼠李素和异鼠李素-3-糖苷是具有多种健康益处的前两种黄酮醇。然而,沙米中黄酮类化合物的分子调控机制尚不清楚。基于一个普通的花园试验，在这项研究中，对六种沙米生态型的营养期和生殖期进行了综合转录组和类黄酮靶向代谢组学分析，其原始栖息地覆盖了各种环境因素梯度。多元线性逐步回归分析显示，沙米中黄酮的积累与温度和UVB呈正相关，而受降水和日照时间的负面影响。分别。加权共表达网络分析（WGCNA）表明bHLH和MYB转录因子（TF）家族可能在沙稻黄酮生物合成调控中起关键作用。在生态型DL和生态型AEX之间总共鉴定了22,778个差异表达基因（DEGs），大多数环境因素的两个极端，其中85DEGs可能与已知的类黄酮生物合成途径有关。构建了一个包含本研究中检测到的23种类黄酮的沙米类黄酮生物合成网络。基因家族植物类黄酮O-甲基转移酶（AsPFOMT）和UDP-葡糖醛酸基转移酶（AsUGT78D2）在转录水平上被鉴定和表征，被认为是沙米中异鼠李素和异鼠李素-3-糖苷的合成酶，分别。在DL生态型中发现了芦丁和异鼠李素的生物合成之间的权衡，这可能是由于面对环境变化时代谢通量的重定向。本研究为在分子水平上理解沙米类黄酮的生物合成提供了有价值的信息,为该功能性资源牧草的精准开发和利用奠定了基础。
Agriophyllum squarrosum (L.) Moq., well known as sandrice, is an important wild forage in sandy areas and a promising edible and medicinal resource plant with great domestication potential. Previous studies showed flavonoids are one of the most abundant medicinal ingredients in sandrice, whereby
isorhamnetin and
isorhamnetin-3-glycoside were the top two flavonols with multiple health benefits. However, the molecular regulatory mechanisms of flavonoids in sandrice remain largely unclear. Based on a common garden
trial, in this
study, an integrated transcriptomic and flavonoids-targeted metabolomic analysis was performed on the vegetative and reproductive periods of six sandrice ecotypes, whose original habitats covered a variety of environmental factor gradients. Multiple linear stepwise regression analysis unveiled that flavonoid accumulation in sandrice was positively correlated with temperature and UVB and negatively affected by precipitation and sunshine duration, respectively. Weighted co-expression network analysis (WGCNA) indicated the bHLH and MYB transcription factor (TF) families might play key roles in sandrice flavonoid biosynthesis regulation. A total of 22,778 differentially expressed genes (DEGs) were identified between ecotype DL and ecotype AEX, the two extremes in most environmental factors, whereby 85 DEGs could be related to known flavonoid biosynthesis pathway. A sandrice flavonoid biosynthesis network embracing the detected 23 flavonoids in this research was constructed. Gene families Plant flavonoid O-methyltransferase (AsPFOMT) and UDP-glucuronosyltransferase (AsUGT78D2) were identified and characterized on the transcriptional level and believed to be synthases of isorhamnetin and
isorhamnetin-3-glycoside in sandrice, respectively. A trade-off between biosynthesis of rutin and
isorhamnetin was found in the DL ecotype, which might be due to the metabolic flux redirection when facing environmental changes. This research provides valuable information for understanding flavonoid biosynthesis in sandrice at the molecular level and laid the foundation for precise development and utilization of this functional resource forage.
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