Signaling to Cell Intercalation in Arabidopsis

拟南芥中细胞嵌入的信号转导

基本信息

批准号：
7484089
负责人：
Zhenbiao Yang
金额：
$ 27.91万
依托单位：
UNIVERSITY OF CALIFORNIA RIVERSIDE
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-09-01 至 2011-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7484089
关键词：
Actins Animals Appearance Arabidopsis Auxins Award Biochemical Biochemical Genetics Biological Biological Assay Biological Models Candidate Disease Gene Cells Class Complex Cytoskeleton Data Development Embryo Embryonic Development Epidermis Event Failure Genetic Goals Grant Growth Guanine Nucleotide Exchange Factors Guanosine Triphosphate Phosphohydrolases Health Hormones Human Image Intention Investigation Knock-out Knowledge Left Link Lobe Localized Mass Spectrum Analysis Mediating Methods Microtubules Molecular Molecular Cloning Morphogenesis Neural Tube Defects Organism Organogenesis Pathway interactions Perception Phosphotransferases Plant Leaves Plant Model Plants Pregnancy Process Protein Kinase Proteins RIPK2 gene Receptor Signaling Regulation Research Research Personnel Role Shapes Signal Pathway Signal Transduction Signaling Molecule System Testing Time Tissues United States National Institutes of Health Work Yang base developmental disease insight intercalation mutant novel plant growth/development programs receptor rho rho GTP-Binding Proteins spatiotemporal

项目摘要

The long-term goal of this project is to understand the underlying signaling mechanisms of cell intercalation, in which neighboring cells change their shapes to become intercalated with each other. Cell intercalation is critical for the proper development and morphogenesis of multi-cellular organisms. Cell intercalation is required for the process of convergent extension during gastrulation, neurulation, axis elongation, and organogenesis of animal and human embryos. However, signals and pathways governing this fundamental process are poorly characterized, though some underlying signaling events (e.g., Rho GTPases and the cytoskeleton) are known to be conserved across animal and plant kingdoms. In the model plant Arabidopsis, cell intercalation is important for the development of the leaf epidermis, in which pavement cells develop intercalary lobes and indentations to form the jigsaw-puzzle appearance. The Pi's group has developed the pavement cell as a model system for cell intercalation, and has established the first framework of a Rho GTPase-dependent intracellualr signaling network that controls this process. It is composed of two counteracting pathways: a ROP2-RIC4-actin pathway activating lobe formation and a ROP6-RIC1- microtubule pathway promoting indentation. In this project, signals, receptors and new components will be determined and linked to this framework. In aim 1, signaling events activating the ROP2 GTPase, e.g., signaling by the SPK1 ROP guanine nucleotide exchange factor, will be investigated using biochemical, genetic, and cell biological methods. In aim 2, molecules upstream of the ROP6 GTPase will be determined using similar approaches, and the intercellular signaling between the ROP6 and the ROP2 pathways will be investigated to understand how lobing and indenting are coordinated between the neighboring cells. Aim 3 is to investigate how auxin gradients, acting as a developmental signal, induce intercalary growth. A combination of rop mutants and biochemical and cell biological assays will be used to determine whether auxin activates the ROP2 or ROP6 pathway. The TMK receptor-like kinases that are required for intercalary growth will be tested for their participation in auxin perception. From these aims, a comprehensive picture of the molecular and cellular mechanisms for intercalary growth will be revealed. Given the conservation of the signaling mechanisms underlying cell intercalation across plants and humans, the knowledge gained from this research may provide new insights into our understanding of convergent extension. Because failure in convergent extension causes neural tube defects (NTDs), a common developmental disorder (1 out of 1000 pregnancies), this research is relevant to human health improvements. ^_^^

该项目的长期目标是了解细胞嵌入的潜在信号机制，其中相邻细胞改变其形状以相互插入。细胞嵌入是对于多细胞生物的正常发育和形态发生至关重要。细胞嵌入是原肠胚形成、神经形成、轴伸长期间的会聚伸展过程所需动物和人类胚胎的器官发生。然而，控制这一基本原理的信号和途径尽管一些潜在的信号事件（例如，Rho GTPases 和众所周知，细胞骨架在动物和植物界中是保守的。在模式植物拟南芥中，细胞嵌入对于叶表皮的发育很重要，其中路面细胞发育嵌入的裂片和凹痕形成拼图外观。 Pi 的团队开发了路面细胞作为细胞插层的模型系统，并建立了第一个 Rho 框架 GTP 酶依赖性细胞内信号网络控制着这一过程。它由两个组成抵消途径：激活叶形成的 ROP2-RIC4-肌动蛋白途径和 ROP6-RIC1- 微管通路促进压痕。在这个项目中，信号、受体和新成分将被确定并与该框架相关联。在目标 1 中，信号事件激活 ROP2 GTPase，例如， SPK1 ROP 鸟嘌呤核苷酸交换因子的信号传导，将使用生化方法进行研究，遗传和细胞生物学方法。在目标 2 中，将确定 ROP6 GTPase 上游的分子使用类似的方法，ROP6 和 ROP2 通路之间的细胞间信号传导将是研究目的是了解相邻单元格之间如何协调分瓣和缩进。目标 3 的目的是研究生长素梯度如何作为发育信号诱导闰生长。一个 rop 突变体与生化和细胞生物学测定的组合将用于确定是否生长素激活 ROP2 或 ROP6 途径。闰所需的 TMK 受体样激酶将测试它们对生长素感知的参与。从这些目标出发，可以全面了解层间生长的分子和细胞机制将被揭示。鉴于植物和人类细胞嵌入背后信号机制的保守性，从这项研究中获得的知识可能会为我们对融合的理解提供新的见解扩大。由于会聚延伸失败会导致神经管缺陷 (NTD)，这是一种常见的疾病发育障碍（千分之一的怀孕），这项研究与人类健康相关改进。 ^_^^