Role of miR156-targeted SQUAMOSA PROMOTER BINDING PROTEIN-LIKE transcription factors in floral transition

miR156靶向SQUAMOSA启动子结合蛋白样转录因子在花转变中的作用

• 批准号: 1947274
• 负责人: Mingli Xu
• 金额: $ 71.02万
• 依托单位: University of South Carolina at Columbia
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1947274&HistoricalAwards=false
• 关键词: Role; miR156; targeted; SQUAMOSA; PROMOTER

Flowering is one of the major decisions in a plant’s life cycle and is required for producing the seeds and fruits that support life on earth. It is important to understand the mechanism of this process so that ways can be found to respond to the challenges of climate change and to the pressures on agriculture from an ever-increasing population. In many species, plants make a unique type of leaf before making flowers. This phase is the initial stage of reproductive development, and may be quite short in an annual plant, but is extended in long-lived perennial plants, many of which are of considerable ecological and economic importance. This project will investigate how a group of proteins, known as SPB box transcription factors, specify this initial stage of reproductive development in the model genetic system, Arabidopsis thaliana. Discoveries in model systems can provide key information that can be translated to crop plants in the future. In addition to providing new insights into the mechanism of flowering, this project will provide training opportunities for a postdoctoral researcher, a graduate student, and undergraduate students. Some of the mutants studied in this project have visible phenotypes and could be used to study genetics and plant development in K-12 classrooms. One to two K-12 schoolteachers from South Carolina will be engaged in this project each summer, with guidance on how to apply some materials from the project in their classrooms. As a plant grows, the shoot apical meristem produces lateral organs (leaves and axillary buds) with different developmental identities—juvenile leaves, adult leaves, cauline leaves and flowers. In Arabidopsis, the transition between the juvenile vegetative (V1) and adult vegetative (V2) phase is regulated by miR156 and its targets, SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors, whereas the transition between the cauline leaf (V3) and floral (R) phase is regulated by the floral meristem identity genes, LEAFY and APETALA1. Flowering-time genes regulate the V2 to V3 transition (floral induction), but genes that specify the identity of V3 organs (cauline leaves, secondary inflorescences) are still largely unknown. Mutations in SPL2/SPL9/SPL13/SPL15 produce rosette-like cauline leaves, suggesting that these miR156-targeted SPLs play a key role in promoting the V2 to V3 transition by specifying the V3 organ identity. This project will use a combination of molecular, genetic and biochemical approaches to identify the upstream regulators and downstream targets of these SPLs involved in specifying V3 organ identity. This project is jointly funded by the Plant, Fungal and Microbial Developmental Mechanisms Program and the Established Program to Stimulate Competitive Research (EPSCoR).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

开花是植物生命周期中的主要决定之一，是生产支持地球生命的种子和水果所必需的。重要的是要了解这一过程的机制，以便可以发现如何应对气候变化的挑战以及对人口不断增加的农业压力的挑战。在许多物种中，植物在制作鲜花之前会形成独特的叶子。该阶段是生殖发展的初始阶段，在一年中可能很短，但在长期寿命的多年生植物中扩展，其中许多是生态和经济重要性的考虑。该项目将研究一组称为SPB盒转录因子的蛋白质如何指定模型遗传系统拟南芥中生殖发育的初始阶段。模型系统中的发现可以提供关键信息，这些信息将来可以转化为作物植物。除了提供有关开花机制的新见解外，该项目还将为博士后研究员，研究生和本科生提供培训机会。该项目中研究的一些突变体具有可见的表型，可用于研究K-12教室中的遗传学和植物发育。每年夏天，来自南卡罗来纳州的一到两名K-12学校老师将参与该项目，并提供有关如何在其教室中应用该项目的一些材料的指导。随着植物的生长，芽顶分生组织会产生带有不同发育认同的外侧器官（叶子和腋芽） - 叶片叶子，成年叶子，仙女叶和花朵。在拟南芥中，青少年营养（V1）与成人营养（V2）相之间的过渡受miR156及其靶标，Squamosa启动子结合蛋白（SPL）转录因子的转换，而花卉叶片（V3）和Floral（R）相之间的过渡受Floolal Meristity Meristity senterity sentery septa和APET，apty和APET的过渡。开花时间基因调节V2至V3跃迁（花卉诱导），但是指定V3器官（Cauline叶子，次生花序）的身份的基因仍然在很大程度上未知。 SPL2/SPL9/SPL13/SPL15中的突变产生了玫瑰花结状的泡沫叶，表明这些靶向的miR156靶向的SPL通过指定V3器官标识在促进V2至V3转变方面起着关键作用。该项目将结合分子，遗传和生化方法来识别与指定V3器官身份相关的这些SPL的上游调节剂和下游靶标。该项目由工厂，真菌和微生物发育机制计划和启发竞争性研究的既定计划共同资助（EPSCOR）。该奖项反映了NSF的法定任务，并通过基金会的知识分子优点和更广泛的影响标准通过评估来诚实地诚实地支持支持。