Understanding organ identity in flowers at the level of single cells

在单细胞水平上了解花朵的器官特征

• 批准号: 438774542
• 负责人: Professorin Dr. Kerstin Kaufmann
• 金额: --
• 依托单位: Lehrstuhl für Pflanzliche Zell- und Molekularbiologie
• 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/438774542?language=en
• 关键词: Understanding; organ; identity; flowers; level

Cells in multicellular organisms typically contain the same genetic information, yet display an amazing variation in form and functions. In plants, most developmental processes occur post-embryonically, starting from pools of stem cells that are located in meristems. After floral transition, the Arabidopsis shoot apical meristem produces floral meristems that differentiate into four types of organ: sepals, petals, stamens and carpels. Past research has identified major transcription factors controlling organ specification and differentiation, yet their cell-type specific functions are still poorly understood. In this project, we will combine single cell and cell-type specific genomics techniques with targeted promoter analyses. The aim is to develop a molecular framework for cellular differentiation in flowers, including the characterization of major cell types, their developmental trajectories and the characterization of cell-type specific regulons. More specifically, we will measure mRNA expression at the level of single cells in wildtype and homeotic mutant flowers. To facilitate the classification of cell types, we will additionally employ mRNA-seq in specific GFP-labelled cell populations. The single cell RNA-seq data will allow the prediction of novel cell-type specific marker genes, which will be analyzed using dedicated reporter gene analyses in planta. In a complementary approach, we will analyze the activity of cis-regulatory regions using single cell ATAC-seq. We will generate scATAC-seq datasets for wildtype and homeotic mutant lines, and complement the data by ATAC-seq data from sorted cell populations. Thereby, we will obtain datasets that can be directly compared and integrated with the data from single cell RNA-seq, allowing the identification of combinations of regulatory elements that control cell-type specific gene expression patterns. These can then be validated in planta using reporter gene analysis in developing floral meristems and flowers. Together, the research plan proposed here will bring our understanding of organ specification in flowers to a new level, because we will be able to dissect cell- and organ-specific activities of homeotic transcription factors and predict the corresponding regulatory modules.

多细胞生物体中的细胞通常包含相同的遗传信息，但在形式和功能上却表现出惊人的差异。在植物中，大多数发育过程发生在胚胎后，从位于分生组织中的干细胞池开始。花过渡后，拟南芥顶端分生组织产生花分生组织，分化成四种类型的器官：萼片、花瓣、雄蕊和心皮。过去的研究已经确定了控制器官指定和分化的主要转录因子，但它们在细胞类型中的特定功能仍然知之甚少。在这个项目中，我们将结合单细胞和细胞类型的特定基因组学技术和有针对性的启动子分析。其目的是建立一个花卉细胞分化的分子框架，包括主要细胞类型的特征，它们的发育轨迹和细胞类型特定调节基因的特征。更具体地说，我们将在单细胞水平上测量野生型和同源异型突变花的mRNA表达。为了便于对细胞类型进行分类，我们还将在特定的绿色荧光蛋白标记的细胞群体中使用mRNA-seq。单细胞RNA-SEQ数据将允许预测新的细胞类型特定标记基因，这些基因将在Planta中使用专门的报告基因分析进行分析。在一种补充方法中，我们将使用单细胞ATAC-seq来分析顺式调节区的活性。我们将为野生型和同源异型突变系生成scATAC-seq数据集，并通过来自已排序细胞群体的atac-seq数据来补充数据。因此，我们将获得可以直接与来自单细胞RNA-SEQ的数据进行比较和整合的数据集，从而能够识别控制细胞类型特定基因表达模式的调控元件的组合。然后，这些可以在植物中验证，使用发育的花分生组织和花的报告基因分析。综上所述，本文提出的研究计划将把我们对花器官特性的理解带到一个新的水平，因为我们将能够剖析同源异型转录因子的细胞和器官特异性活动，并预测相应的调控模块。