Protodermal Stem Cells in the Brachypodium Leaf

短柄草叶中的原真皮干细胞

• 批准号: 467840486
• 负责人: Professor Dr. Michael Raissig
• 金额: --
• 依托单位: Institute of Plant Scienes
• 依托单位国家: 德国
• 项目类别: Research Units
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/467840486?language=en
• 关键词: Protodermal; Stem; Cells; Brachypodium; Leaf

Protodermal stem cells are meristematic cells in the epidermal L1 layer at the base of the developing grass leaf. These stem cells have the capacity to produce all epidermal cell types of a grass leaf like the sealing and stabilizing pavement cells, gas-exchanging stomatal complexes, leaf-rolling bulliform cells and the functionally enigmatic but probably herbivore-deterring prickle hair cells and silica cells. Many of these epidermal cell types do not exist in eudicot model systems like Arabidopsis (e.g. bulliform cells, prickle hair cells) or show grass-specific features (e.g. stomata). As the ultimate barrier shielding the “inner” leaf physiology from “outer” abiotic and biotic stressors, the leaf epidermis is absolutely essential to plant survival. Yet, little is known regarding how protodermal stem cells terminate their pluripotent state and commit to distinct developmental trajectories to make the manifold cell types of the grass leaf epidermis. Here, I propose to use the model grass Brachypodium distachyon—a wild grass that can be used as a model system for Pooid grasses like wheat and barley—to decipher how and where protodermal stem cells lose pluripotency and branch into distinct developmental trajectories. To this end, we will use single-cell transcriptomics, developmental genetics and microscopy. We will leverage my lab’s extensive collection of Brachypodium resources and our immediate access to a mutant Brachypodium collection, which is fully resequenced with all mutations exactly mapped to genomic locations (NaN population). Together, this project will produce an unprecedented resolution of protodermal stem cell trajectories in Brachypodium, test the role of key transcription factor families regulating epidermal lineage trajectory commitment and spatially map where exactly lineage commitment occurs in the meristematic zone of the grass leaf.

原胚层干细胞是位于发育中的草叶底部的表皮层L1层的分生组织细胞。这些干细胞有能力产生草叶的所有表皮细胞类型，如封闭和稳定的路面细胞、气体交换气孔复合体、卷叶的泡状细胞以及功能神秘但可能阻止食草动物的刺毛细胞和二氧化硅细胞。许多这样的表皮细胞类型在拟南芥等优生模型系统中并不存在(例如，泡状细胞、刺毛细胞)，或者表现出草特有的特征(例如，气孔)。作为保护叶片内部免受外部非生物和生物胁迫的终极屏障，叶表皮对植物的生存是绝对必要的。然而，关于原胚层干细胞如何终止其多能性状态并致力于不同的发育轨迹以形成草叶表皮的多种细胞类型，人们知之甚少。在这里，我建议使用模式草Brachypodium disachyon-一种可以用作小麦和大麦等杂草的模式系统的野草-来破译原胚层干细胞如何以及在哪里失去多能性并分支成不同的发育轨迹。为此，我们将使用单细胞转录学、发育遗传学和显微技术。我们将利用我的实验室广泛收集的Brachypodium资源，以及我们立即获得的突变Brachypodium集合，该集合与准确定位到基因组位置(NaN种群)的所有突变完全重新测序。综上所述，该项目将产生前所未有的原始胚层干细胞轨迹的分辨率，测试关键转录因子家族调节表皮谱系轨迹承诺的作用，并在空间上绘制草叶分生组织区发生谱系承诺的确切位置。