Feedback between multiple signaling modes in control of a plant stem cell niche

控制植物干细胞生态位的多种信号传导模式之间的反馈

• 批准号: 8894020
• 负责人: ELLIOT M MEYEROWITZ
• 金额: $ 31.3万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8894020
• 关键词: Address; Affect; Affinity Chromatography; Anabolism; Angiosperms; Animal Model; Animals; Apical; Arabidopsis; Attention; Behavior; Binding; Biological Models; Biology; Cell Communication; Cell Proliferation; Cell division; Cells; ChIP-seq; Chromatin; Collection; Communication; Complex; Computer Simulation; Coupled; Cytokinins; Data; Development; Differentiated Gene; Disease; Encapsulated; Epidermis; Experimental Models; Feedback; Gene Expression; Gene Expression Profile; Gene Targeting; Genes; Genetic; Genetic Transcription; Genome; Genomics; Goals; Growth and Development function; Health; Hormonal; Hormones; Hybrids; Image; Imaging Techniques; In Vitro; Laboratories; Lead; Libraries; Life; Location; Maintenance; Meristem; Metabolism; Methods; Microscopy; Modality; Modeling; Molecular; Molecular Profiling; Mouse-ear Cress; Mutation; Nuclear; OmpR protein; Organism; Pathway interactions; Peptide Signal Sequences; Peptides; Plant Shoots; Plant Stems; Plants; Proteins; Publishing; RNA; Regulation; Regulator Genes; Reporter; Research; Resolution; Ribosomes; Role; Series; Signal Pathway; Signal Transduction; Signaling Molecule; Stem Cell Development; Stem cells; Sum; Surface; System; Techniques; Technology; Testing; Therapeutic; Tissues; Transgenes; Transgenic Organisms; Translating; Yeasts; cell behavior; cell type; comparative; design; feeding; gain of function; health application; human disease; human stem cells; imaging modality; in vivo; intercellular communication; mutant; new technology; novel; novel strategies; novel therapeutics; organ regeneration; overexpression; receptor; regenerative; research study; response; screening; stem cell biology; stem cell niche; stem cell population; tissue regeneration; transcription factor; transcriptome sequencing; yeast two hybrid system

DESCRIPTION (provided by applicant): Understanding the mechanism of maintenance and differentiation of stem cell populations is a central scientific issue on the path to realizing thefull therapeutic potential of stem cells in the treatment of human disease. Characterizing the cellular signals that maintain and regulate stem cell populations will lead to a new appreciation of the principles by which living organisms control growth and development and to the development of new technologies to utilize stem cells in health applications including tissue and organ regeneration. The proposed study, by characterizing the factors that regulate stem cell proliferation, differentiation, and specification in a model system, will reveal new principles of stem cell niche organization. The research proposed is designed to answer the central unanswered question in stem cell biology: what is the mechanism by which cell-cell communication instructs cellular behavior in stem cell populations? Because of its amenability to the full spectrum of methods from modern systems and genomic biology, as well as the remarkable regenerative abilities of plants, the shoot apical meristem (SAM) of the flowering plant Arabidopsis thaliana will be used as a model system. Two key signaling pathways, and their interactions, will be studied: the CLAVATA-WUSCHEL peptide signaling pathway and the hormonal cytokinin signaling pathway. The result of accomplishing the aims of the proposal will be a new level of understanding of stem cell niches, and the principles of feedback, signaling, and local cell type response that allow them to serve as permanent and regulated reservoirs of cells for creation of tissues. The experiments will lead to a new level of sophistication in our understanding of development, and of stem cell regulation in plants; and therefore to a more complete understanding of, and comparative view of, the principles of stem cell regulation in both plants and animals. Each aim will use non-invasive live imaging techniques that are particularly effective in plants, because their stem cells are near the surface, and transgenic reporter transgenes, as well as an extensive array of mutations that change the regulation of stem cell behavior. The goal of the first aim is a full characterization of the mechanisms by which alterations in the levels of the hormone cytokinin affect the different domains of the SAM stem cell niche, both directly, via regulation of the peptide signaling pathway, and by the multiple feedbacks of the hormone signaling system on itself. The second aim is a systems approach to characterize the cytokinin signaling pathway from receptor to response regulator transcription. Using the novel TRAP-seq and INTACT methods, cytokinin target genes will be characterized at cellular and molecular resolution. The third aim is an unbiased yeast-one hybrid screen to identify transcriptional regulators of cytokinin signaling, and cytokinin biosynthetic genes. The fourth and final aim is to use the data generated through these approaches to parameterize computational models that encapsulate the complex feedbacks in the system, to test new hypotheses of the mechanism by which cell-cell communication regulates the SAM stem cell niche.

描述(由申请人提供)：了解干细胞群体维持和分化的机制是实现干细胞在人类疾病治疗中的全部治疗潜力的道路上的一个中心科学问题。确定维持和调节干细胞种群的细胞信号的特征将使人们重新认识生物控制生长和发育的原理，并开发新技术，在包括组织和器官再生在内的健康应用中利用干细胞。这项拟议的研究，通过在模型系统中表征调控干细胞增殖、分化和规范的因素，将揭示干细胞生态位组织的新原理。提出的这项研究旨在回答干细胞生物学中一个核心的悬而未决的问题：干细胞群体中细胞-细胞交流指导细胞行为的机制是什么？拟南芥的顶端分生组织(SAM)由于其对现代系统和基因组生物学方法的适应性，以及植物显著的再生能力，将被用作模式系统。将研究两条关键的信号通路及其相互作用：CLAVATA-WUSCHEL肽信号通路和激素细胞分裂素信号通路。实现该提案的目标的结果将是对干细胞生态位以及反馈、信号和局部细胞类型反应的原理的理解达到新的水平，使它们能够作为永久的和受调控的细胞储存库来创造组织。这些实验将使我们对植物的发育和干细胞调节的理解达到一个新的成熟水平；因此，我们对植物和动物的干细胞调节的原理有了更全面的理解和比较的看法。每个目标都将使用对植物特别有效的非侵入性实时成像技术，因为它们的干细胞接近表面，转基因报告基因，以及一系列改变干细胞行为规则的突变。第一个目标是全面描述激素细胞分裂素水平的变化通过调节多肽信号通路和激素信号系统本身的多重反馈直接影响SAM干细胞生态位不同区域的机制。第二个目标是用系统的方法来描述从受体到反应调节转录的细胞分裂素信号通路。使用新的TRAP-SEQ和完整的方法，细胞分裂素的靶基因将在细胞和分子分辨率上进行表征。第三个目标是无偏见的酵母-One杂交筛选，以确定细胞分裂素信号和细胞分裂素生物合成基因的转录调节因子。第四个也是最后一个目标是使用通过这些方法产生的数据来参数化计算模型，这些计算模型封装了系统中复杂的反馈，以测试细胞间通信调节SAM干细胞生态位的机制的新假设。