Analysis of a gene regulatory network underlying trait divergence between annual and perennial plants

一年生和多年生植物性状差异背后的基因调控网络分析

• 批准号: 490751140
• 负责人: Professor Dr. George Coupland, Ph.D.
• 金额: --
• 依托单位: Architecture and Functioning of Fruit species (AFEF)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/490751140?language=en
• 关键词: Analysis; gene; regulatory; network; underlying

The timing of reproduction strongly contributes to fitness and yield in annual and perennial plants. Here, we aim to decipher molecular mechanisms and the regulatory logic that control the switch in meristem identity that occurs during floral transition, and its subsequent stabilization during inflorescence development. We use a comparative approach among annual and perennial species, including an economically important crop, to broaden the relevance of our findings and to determine the flexibility in the underlying mechanisms in different developmental contexts and in response to different environmental and endogenous signals. Floral transition is the first step in plant reproduction, it is controlled by environmental and endogenous cues, and its timing is critical to fitness in natural populations or to yield in agriculture. During floral transition the developmental identity of the shoot apical meristem and/or axillary meristems is altered causing them to switch from vegetative meristems that form leaf primordia to inflorescence meristems that produce floral primordia. This transition is a binary switch that is usually irreversible, so that after the switch the identity of the inflorescence meristem is stable and does not revert back to a vegetative meristem. We propose that a bistable-switch mechanism reinforced by feedback loops acts at the shoot meristem to control the transition, and that the switch mechanism is biased by environmental signals to allow the transition to occur. Our model proposes that APETALA2 (AP2) and APETALA2-LIKE (AP2-LIKE) transcription factors maintain the vegetative state, while the SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) and FRUITFULL (FUL) MADS box transcription factors together with the non-coding microRNA172 (miR172) maintain the reproductive state. These two sets of factors form a mutually repressive motif that is biased from the vegetative to reproductive state by environmental cues that induce SOC1, FUL and MIR172 transcription in the shoot meristem. We propose to test this model in annual and perennial crucifer species, Arabidopsis thaliana and Arabis alpina, respectively, as well as in apple trees using state of the art transcriptomics, transgenic and genetic approaches. These experiments will form a basis for quantitative modelling of the floral transition, a crucial stage in plant development. Furthermore, we propose to identify whether there is genetic variability in the switch mechanism in apple trees in relation to the undesired alternate bearing phenomenon. This will have practical significance in manipulating reproduction patterns and yield of crops.

繁殖时机对一年生和多年生植物的适合度和产量有很大贡献。在这里，我们的目标是破译分子机制和调控逻辑，控制开关分生组织身份发生在花的过渡，其随后的稳定在花序发育过程中。我们使用一年生和多年生物种之间的比较方法，包括经济上重要的作物，以扩大我们的研究结果的相关性，并确定在不同的发展背景下，并在不同的环境和内源性信号响应的潜在机制的灵活性。花型转变是植物繁殖的第一步，受环境和内源因素的控制，其发生的时间对自然种群的适应性和农业产量都至关重要。在花的转变过程中，茎顶端分生组织和/或腋生分生组织的发育特性发生改变，导致它们从形成叶原基的营养分生组织转变为产生花原基的花序分生组织。这种转变是一种二元转换，通常是不可逆的，因此在转换后，花序分生组织的身份是稳定的，不会恢复到营养分生组织。我们建议，一个双稳态开关机制加强反馈回路的行为在拍摄分生组织控制过渡，和开关机制偏置环境信号，允许过渡发生。我们的模型提出，APETALA 2（AP 2）和APETALA 2-LIKE（AP 2-LIKE）转录因子维持植物状态，而CONSTANS 1（SOC 1）和FRUITFULL（FUL）MADS盒转录因子与非编码microRNA 172（miR 172）一起维持生殖状态。这两组因子形成了一个相互抑制的基序，该基序通过诱导SOC 1、FUL和MIR 172在茎分生组织中转录的环境线索从营养状态偏向于生殖状态。我们建议在一年生和多年生十字花科植物，拟南芥和Arabis alpina，分别测试这个模型，以及在苹果树使用最先进的转录组学，转基因和遗传方法。这些实验将为植物发育的关键阶段--花的转变--的定量建模奠定基础。此外，我们建议，以确定是否有遗传变异的开关机制在苹果树有关的不希望的交替轴承现象。这对调控作物的繁殖模式和产量具有实际意义。