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; 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.

开花的时机是一个重要的自适应特征。因为开花时间和持续时间对其他自适应特征具有深远的影响，例如对害虫的抗性以及对高温或低温或干旱等非生物应力的耐受性，因此假设在基本的调节网络之间假设串扰。尽管开花网络和应力信号通路是经过充分研究的，但两条途径之间的联系仍然留下了悬而未决的问题，尽管重要的联系将是标记辅助育种计划中非生物应力适应的绝佳标志。微RNA（miRNA）是一类小的调节性RNA，在许多调节途径中都起着重要作用。已经建立了关联，将miRNA与发芽，开花和衰老以及对非生物压力的反应联系起来。他们也是作为串扰使者的有前途的候选人。虽然在模型植物中建立了miRNA研究，但在确定miRNA介导的性状调节范围和作用的范围和作用中，仅取得了较小的进步。通过挖掘基因组和转录组数据集，我们揭示了Frigida（FRI）A基因组同源物（FRI）中的miRNA结合位点，一个关键的花卉调节剂也与非生物应力适应有关。我们发现，在渗透应激下，在耐旱的B. rapA基因型中，周围的相应副本被上调，而在干旱敏感的基因型中观察到下调，并且在没有压力的情况下。基于中央开花调节剂周五，miRNA和干旱应力反应的这种潜在相互作用，我们旨在研究纳普斯B. napus基因型中不同组织中的这种相互作用，在压力和无压力条件下表现出对干旱应激的差异反应。为此，我们将在施加压力之前和之后从植物生命周期期间的不同时间点提取和序列miRNA。同时，选定的BNA.FRI同源物和其他潜在的miRNA靶标将通过QRT-PCR量化。表达模式将与生理影响有关开花和干旱反应的影响，并通过在大型范围系统中的详细表型来评估，该系统可以在类似于田间土壤环境的条件下精确控制干旱应力。