Molecular regulation and ecological consequences of chemodiversity in Solanum dulcamara

龙葵植物产生大量的甾体糖生物碱(SGAs)，它们可能对草食动物和病原体具有抗性。在第一阶段，我们重点研究了两种叶片SGA化学类型：在C5，6键(U)不饱和的SGAs的植株和产生也饱和的(S)SGAs的植株。我们的目的是在这些SGA化学类型中确定更多的化学多样性水平，并研究其生态后果。利用LC-QTOF-MS分析发现，U和S两个化学型的根代谢谱比它们的叶更相似。初生根和不定根含有不同的SGAs亚群，并且像花一样，也产生含氧糖类固醇。使用合成的类固醇化合物，我们现在正在测试这些微小的结构差异如何在生物检测中影响食草动物。本研究设计了一个普通园艺实验，分别为1年级、5年级和7年级。控制U和S化型频率的结果表明，个体化型和小区化学多样性都影响果实和种子产量。这些数据将与P9共享，用于对进化轨迹进行建模。我们与P8一起组装并注释了一个S化学型的基因组。结合食草动物和茉莉酸诱导实验，我们确定了参与调节、生物合成和运输SGAs以及萜类合成酶的基因。在第二阶段，我们的目标是了解根化学多样性如何影响地下相互作用，以及个体内化学多样性如何受到分子调控。我们将通过增加来自P3的田间采集的个体来扩大我们对叶、根和花的代谢物谱的比较分析。使用P10开发的R包，我们将分析根是否像在P1、P3和P5中一样，总体上具有低于叶或花的种内化学多样性水平。我们建议将从一篇概念性文件中获得的知识与研究组的其他项目相结合，以探索“如何定义个人化学型？”这一基本问题。使用一个代表不同根代谢物图谱的子集，我们将测试根化学多样性如何影响与根草食动物、线虫和有益微生物的相互作用(与P7)。此外，我们将评估这些不同的地下相互作用将如何影响叶片代谢物分布和地上草食动物。植物和食草动物的性能数据将与P9共享以进行建模。最后，对于P8，我们将使用第一阶段产生的基因组数据来分析植物内部器官中SGAs和萜类化合物个体内变异的分子调控。我们将通过提供元素(C，N，P)分析来参与COR化学多样性-可塑性实验。

Solanum dulcamara plants produce a large variety of steroidal glycoalkaloids (SGAs), which may provide resistance to herbivores and pathogens. In the first phase, we focused on two leaf SGA chemotypes: plants with SGAs that are unsaturated at the C5,6 bond (U) and those producing also saturated (S) SGAs. Our aim was to identify additional levels of chemodiversity in these SGA chemotypes as well as to study the ecological consequences. Using LC-qTOF-MS analysis, we found that root metabolic profiles of U and S chemotypes are more similar than those of their leaves. Primary and adventitious roots contain different subsets of SGAs, and, like flowers, also produce oxygenated glycosteroids. Using synthetic steroidal compounds, we are now testing how these small structural differences affect herbivores in bioassays. A common garden experiment was designed with P1, P5 and P7. Manipulating U and S chemotype frequencies revealed that both individual chemotype and plot chemodiversity affected fruit and seed production. These data will be shared with P9 for modelling evolutionary trajectories. Together with P8 we assembled and annotated the genome of one S chemotype. Combined with herbivore and jasmonate induction experiments, we identified genes involved in the regulation, biosynthesis and transport of SGAs as well as terpene synthases. In a second phase, we aim to understand how root chemodiversity influences belowground interactions and how intra-individual chemodiversity is molecularly regulated. We will expand our comparative analyses of leaf, root and flower metabolite profiles by adding field-collected individuals from P3. Using the R-package developed by P10, we will analyse whether roots overall have lower levels of intraspecific chemodiversity than leaves or flowers as in P1, P3 and P5. We propose to synthesise the knowledge gained in a conceptual paper with the other projects in the Research Unit to explore the fundamental question of “how to define an individual chemotype?”. Using a sub-set representing contrasting root metabolite profiles, we will test how root chemodiversity impacts interactions with root herbivores, nematodes and beneficial microbes (with P7). In addition, we will assess how these different belowground interactions will impact leaf metabolite profiles and aboveground herbivores. The plant and herbivore performance data will be shared with P9 for modelling. Finally, with P8 we will use the genomic data generated in the first phase to analyse the molecular regulation of intra-individual variation in SGAs and terpenoids among organs within a plant. We will participate in the COR chemodiversity-plasticity experiment by providing elemental (C, N, P) analyses.