Regulation of Flower Initiation and Development

在一年生植物中，包括大多数作物物种，花形成的开始触发了从叶和枝的生物量和资源生产到这些资源在花中形成的种子中分配给下一代的转变。花形成的开始时间和花的正常发育对植物的生存和农业都很重要。了解这些过程的调节将有助于优化生物燃料生产或食品生产的营养阶段的持续时间，并优化食品生产的生殖结构。尽管最近在理解这两个过程的调控方面取得了很大进展，但仍有许多未知之处。植物特异性转录因子LEAFY （LFY）是花形成和早期花发育的主要调控因子。本项目以LFY为切入点，拟南芥为植物模式物种，以解决两个关键问题，这两个问题代表了对花发育理解的主要空白：(1)LFY下游的调控因子是什么，以触发花形成的转换？LFY启动了导致第一朵花形成的一系列事件。尽管这种发育转换对植物的生殖适应性和人类的维持具有重要意义，但LFY诱导的这一转变的关键调节因子仍未确定。该项目将采用一种新颖的遗传方法来解决这个问题。(2) LFY和另一个重要的花发育调控因子MADS盒子转录因子APETALA1如何共同指导形成花分生组织所需的细胞命运变化？现在人们普遍认为LFY和AP1共同协调了花的早期发育。在这个目标中，从最近的基因组数据集中获得的见解将被利用来确定候选调节因子在花形态发生的早期事件中重要，然后阐明它们在植物中的作用。这些花形态发生的早期事件在所有植物系统中都知之甚少，因此这项研究应该产生具有广泛意义的新见解。

In annual plants, which include most crops species, onset of flower formation triggers a transition from biomass and resource production in the leaves and branches to allocation of these resources to the next generation in the seeds formed in the flowers. Both timing of the onset of flower formation and proper flower development are important for plant survival and for agriculture. Understanding the regulation of these processes will allow optimization of the duration of the vegetative phase for biofuel production or food production and optimal elaboration of the reproductive structures for food production. Despite much recent progress in the understanding of the regulation of both of these processes, much remains unknown. The plant specific transcription factor LEAFY (LFY) is a master regulator of the switch to flower formation and of early flower development. This project uses LFY as an entry point and Arabidopsis thaliana as the plant model species to address two key questions that represent major gaps in the understanding of flower development: (1) What are regulators that act downstream of LFY to trigger the switch to flower formation? LFY sets in motion the series of events that result in formation of the first flower. Despite the importance of this developmental switch for plant reproductive fitness and human sustenance, key regulators of this transition that are induced by LFY remain unidentified.The project will take a novel genetic approach to address this question. (2) How do LFY and another important regulator of flower development, the MADS box transcription factor APETALA1 together direct the cell fate changes required to form a floral meristem? It is now widely accepted that LFY and AP1 together orchestrate early flower development. In this aim, insight gained from recent genomic datasets will be harnessed to identify candidate regulators important for early events in flower morphogenesis followed by elucidation of their role in plants. These early events in flower morphogenesis are poorly understood in all plant systems so this investigation should generate novel insight of broad significance.