Flowering time, miRNA regulation and climatic adaptation: Variation in Brassica napus idiotypes under drought stress

开花时间、miRNA 调控和气候适应：干旱胁迫下甘蓝型油菜独特型的变异

• 批准号: 197251172
• 负责人: Professor Dr. Rod Snowdon
• 金额: --
• 依托单位: Lehrstuhl für Pflanzenzüchtung
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/197251172?language=en
• 关键词: Flowering; time; miRNA; regulation; climatic

The timing of flowering is an important adaptive trait. Because flowering time and duration have a profound influence on other adaptive traits, like resistance to pests and tolerance to abiotic stresses like high/low temperatures or drought, a crosstalk is assumed between the underlying regulatory networks. While the flowering network and stress signalling pathways are well-studied, links between the two pathways still leave open questions, although important links would serve as excellent markers for abiotic stress adaptation in marker-assisted breeding programs. Micro-RNAs (miRNA) are a class of small regulatory RNAs that have been found to play an important role in numerous regulatory pathways. Associations have been established linking miRNAs with germination, flowering and senescence as well as responses to abiotic stress. They are also promising candidates as crosstalk messengers. While miRNA research is established in model plants, only minor progress has been made in determining the scope and action of miRNA-mediated trait regulation in crops. By mining genomic and transcriptome datasets we revealed miRNA binding sites in an A-genome homologues of FRIGIDA (FRI), a key floral regulator also implicated in abiotic stress adaptation. We found the corresponding copy of FRI to be upregulated in a drought-resistant B. rapa genotype under osmotic stress, whereas down-regulation was observed in drought-sensitive genotypes and in the absence of stress. Based on this potential interaction of the central flowering regulator FRI, miRNA and drought stress responses, we aim to investigate this interaction within different tissues in B. napus genotypes that exhibit differential responses to drought stress under stressed and non-stressed conditions. For this purpose, we will extract and sequence miRNA from different time points during the plant lifecycle before and after stress application. At the same time, selected Bna.FRI homologues and other potential miRNA targets will be quantified by qRT-PCR. Expression patterns will be associated to physiological influences in terms of flowering and drought response, assessed by detailed phenotyping in a large-container system which allows exact control of drought stress under conditions resembling a field soil environment.

开花时间是一个重要的适应性特征。由于开花时间和持续时间对其他适应性特征有深远的影响，例如对害虫的抵抗力和对高/低温或干旱等非生物胁迫的耐受性，因此假设潜在的调控网络之间存在串扰。虽然开花网络和胁迫信号传导途径已得到充分研究，但这两种途径之间的联系仍然存在悬而未决的问题，尽管重要的联系可以作为标记辅助育种计划中非生物胁迫适应的极好标记。 Micro-RNA (miRNA) 是一类小调控 RNA，已被发现在许多调控途径中发挥重要作用。 miRNA 与发芽、开花和衰老以及对非生物胁迫的反应之间的关联已经建立。他们也是相声使者的有前途的候选人。虽然 miRNA 研究是在模型植物中建立的，但在确定 miRNA 介导的作物性状调控的范围和作用方面只取得了很小的进展。通过挖掘基因组和转录组数据集，我们揭示了 FRIGIDA (FRI) 的 A 基因组同源物中的 miRNA 结合位点，FRIGIDA 是一种关键的花调节因子，也与非生物胁迫适应有关。我们发现，在渗透胁迫下，抗旱白菜基因型中相应的 FRI 拷贝上调，而在干旱敏感基因型和无胁迫的情况下，FRI 的相应拷贝则下调。基于中央开花调节因子 FRI、miRNA 和干旱胁迫反应之间的这种潜在相互作用，我们旨在研究甘蓝型油菜基因型不同组织内的这种相互作用，这些基因型在胁迫和非胁迫条件下对干旱胁迫表现出不同的反应。为此，我们将提取植物生命周期中胁迫前后不同时间点的 miRNA 并进行测序。同时，选定的 Bna.FRI 同源物和其他潜在的 miRNA 靶标将通过 qRT-PCR 进行定量。表达模式将与开花和干旱反应方面的生理影响相关，通过大容器系统中的详细表型评估，该系统允许在类似于田间土壤环境的条件下精确控制干旱胁迫。