Mechanistic analysis of the transition from juvenility to maturity in perennial Arabis alpina and comparison with Brassica crop species

多年生高山南芥幼年向成熟转变的机理分析及与芸苔属作物的比较

• 批准号: 196894865
• 负责人: Professor Dr. George Coupland, Ph.D.
• 金额: --
• 依托单位: Abteilung Entwicklungsbiologie der Pflanzen
• 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 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/196894865?language=en
• 关键词: Mechanistic; analysis; transition; juvenility; maturity

Many perennial plants exhibit a clearly defined juvenile phase during which they will not flower even if exposed to inductive environmental cues. We developed Arabis alpina, a member of the Brassicaceae, as a herbaceaous perennial model. In this species juvenile plants do not flower in response to vernalization, and we found that the progressive decline of miRNA156 acts as a timer defining the duration of the juvenile phase. Here we propose to deepen our knowledge of juvenility in perennials. First we will identify targets of miRNA156 that underlie this trait. In A. alpina 10 mRNAs encoding different SQUAMOSA PROMOTER BINDING LIKE PROTEIN (SPL) transcription factors are targets of miRNA156. Five of these are expressed around floral induction and orthologues of A. thaliana genes implicated in flowering. We will generate mutations that prevent miRNA156 binding to each of these 5 mRNAs and test which of the mutations reduce the juvenile phase by enabling younger plants to respond to vernalization. Secondly, we will exploit existing populations made by crossing A. alpina and A. montbretiana, an annual sister of A. alpina with no detectable juvenile phase, to genetically map and isolate loci that confer the difference in juvenility between the two species. Thirdly, we will extend our characterization of the flowering responses of A. alpina accessions collected across its European range to test for intra-species natural-genetic variation for juvenility. Fourthly, we will pursue hybrid crosses carried out between annual and perennial species in the Brassica genus and explore whether allelic variation exists in these species at loci identified in Arabis as controlling the juvenile phase. These experiments build on our earlier work in the priority programme to elucidate a major flowering trait differing between annuals and perennials and to extend the results to crops.

许多多年生植物表现出明确定义的幼年期，在此期间，即使暴露于诱导环境线索，它们也不会开花。我们开发了高山南芥，一个成员，作为一个草本多年生模式。在这个物种中，幼年植物不会响应春化而开花，我们发现miRNA 156的逐渐下降充当了定义幼年期持续时间的计时器。在这里，我们建议加深我们对多年生植物幼年期的认识。首先，我们将确定miRNA156的靶点，这些靶点是该性状的基础。以. alpina 10编码不同的鳞状细胞启动子结合样蛋白（SPL）转录因子的mRNA是miRNA156的靶点。其中5个在成花诱导和A.与开花有关的拟南芥基因。我们将产生阻止miRNA156与这5种mRNA结合的突变，并测试哪些突变通过使较年轻的植物对春化反应来减少幼年期。第二，我们将利用现有的种群，通过交叉A。alpina和A. montbretiana是A.没有检测到的幼年期，遗传图谱和分离基因座，赋予两个物种之间的幼年差异。第三，我们将扩展我们的开花反应的A。在其欧洲范围内收集的高山品种，以测试种内的自然遗传变异的幼龄。第四，我们将继续进行杂交一年生和多年生物种之间进行芸苔属，并探讨是否存在等位基因变异，这些物种在基因座确定在南芥控制少年阶段。这些实验建立在我们在优先方案中的早期工作的基础上，以阐明一年生植物和多年生植物之间的一个主要开花特性，并将结果扩展到作物。