Carotology: Are apocarotenoids conserved modulators of streptophyte physiology?

胡萝卜学：类胡萝卜素是链霉菌生理学的保守调节剂吗？

• 批准号: 440231723
• 负责人: Professor Dr. Jan de Vries
• 金额: --
• 依托单位: Abteilung Angewandte Bioinformatik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/440231723?language=en
• 关键词: Carotology; apocarotenoids; conserved; modulators; streptophyte

One major challenge for the earliest land plants was overcoming environmental stressors. The plastid of land plants is recognized as a hub for sensing environmental cues by emanating signals, linking plastid and cell physiology. A major class of these signals are the apocarotenoids that emerge from cleavage of carotenoids. In the first funding period of MAdLand, my team and I have garnered data that land plants and streptophyte algae share the production of a range of stress-relevant apocarotenoids known as signals in embryophytes. Now, we want to understand which physiological and molecular responses these molecules elicit. We will test the hypothesis that the apocarotenoids β-cyclocitral, β-ionone, and dihydroactinidiolide induce conserved response patterns tied with stress signaling; for all work, we will use the MAdLand systems Mesotaenium endlicherianum, Zygnema circumcarinatum, and Physcomitrium patens as a land plant reference. To dissect responses to apocarotenoids, we will pursue three synergistic objectives: (1) Measure the impact of apocarotenoids on zygnematophyte and land plant growth, photophysiology, and feedbacks on upstream isoprenoid metabolism; we will illuminate the physiological impact of apocarotenoids shared by land plants and algae. (2) Infer apocarotenoid-triggered global response patterns shared across 600 million years of streptophyte evolution; integrating RNAseq and phosphoproteomic data will pinpoint comprehensive response patterns—candidates for signal transduction to downstream responses—that we can compare to infer a shared homologous signaling network. (3) Probe the conservation of the signaling pathway; while a range of effects of apocarotenoids will be assessed in 1 and 2 in a top-down approach, we also have clear candidates: the phytohormone salicylic acid and (co-)orthologs of ELONGATED HYPOCOTYL 5 (HY5) and PHYTOCHROME INTERACTING FACTOR 3 (PIF3) in Mesotaenium, Zygnema, and Physcomitrium. We will test for the conservation of these routes via (i) inter-species complementation experiments with the algal genes in Physcomitrium patens hy5 and pif knock-out mutants that were already generated and (ii) salicylic acid quantification. In sum, we will obtain comprehensive data on the physiological impact of apocarotenoids; concomitantly, we will delve into signaling using a top-down and a targeted candidate-based approach. Our data will be projected onto the phylogeny of Phragmoplastophyta and compared to published data on land plants and co-expression data on streptophyte algae. Combined, we will address four defined core topics of MAdLand (i-iv): (i) testing that a molecular chassis for modulation of stress physiology through apocarotenoids evolved in streptophyte algae; (ii) inferring that these regulatory patterns occurred in the last common ancestor of land plants and Zygnematophyceae; (iii) probing their role as molecular adaptations in the response to (iv) abiotic terrestrial challenges.

最早的陆地植物面临的一个主要挑战是克服环境压力。陆地植物的质体被认为是通过发出信号，连接质体和细胞生理学来感知环境线索的枢纽。这些信号的主要类别是从类胡萝卜素裂解中出现的脱辅基类胡萝卜素。在MAdLand的第一个资助期，我和我的团队已经收集到的数据表明，陆地植物和链霉菌藻类共同产生一系列与胁迫相关的脱辅基类胡萝卜素，这些类胡萝卜素被称为胚胎植物中的信号。现在，我们想了解这些分子会引发哪些生理和分子反应。我们将测试的假设，脱辅基类胡萝卜素β-环柠檬醛，β-紫罗兰酮，和二氢猕猴桃诱导保守的响应模式与压力信号;对于所有的工作，我们将使用MAdLand系统Mesotaenium endlicherianum，Zygnema circumcarinatum，和立碗藓作为陆地植物参考。为了剖析对脱辅基类胡萝卜素的反应，我们将追求三个协同目标：（1）测量脱辅基类胡萝卜素对合子植物和陆地植物生长、植物生理学的影响，以及对上游类异戊二烯代谢的反馈;我们将阐明陆地植物和藻类共享的脱辅基类胡萝卜素的生理影响。(2)推断脱辅基类胡萝卜素引发的全球响应模式在6亿年的链球菌进化中共享;整合RNAseq和磷酸蛋白质组学数据将精确定位全面的响应模式-信号转导到下游响应的候选者-我们可以比较以推断共享的同源信号网络。(3)探测信号通路的保守性;虽然脱辅基类胡萝卜素的一系列影响将在1和2中以自上而下的方法进行评估，但我们也有明确的候选者：植物激素水杨酸和Mesotaenium，Zygnema和Physcomitrium中的伸长下胚轴5（HY 5）和光敏色素相互作用因子3（PIF 3）的（co-）直系同源物。我们将通过（i）与已经产生的立碗藓hy 5和pif敲除突变体中的藻类基因的种间互补实验和（ii）水杨酸定量来测试这些途径的保守性。总之，我们将获得关于脱辅基类胡萝卜素生理影响的全面数据;同时，我们将使用自上而下和基于目标候选人的方法深入研究信号传导。我们的数据将被投射到Phragmoplastophyta的生殖系统，并与陆地植物的已发表数据和链藻藻类的共表达数据进行比较。结合起来，我们将解决四个定义的核心主题的MAdLand（一至四）：（一）测试，通过apocarotroids进化链藻的应激生理调节的分子底盘;（二）推断，这些监管模式发生在陆地植物和Zygnematophyceae的最后共同祖先;（三）探测它们的作用作为分子适应（四）非生物陆地挑战。