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: 8421442
• 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 2017-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8421442
• 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; 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; public health relevance; 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）：了解干细胞群体的维持和分化机制是实现干细胞在治疗人类疾病中的全部治疗潜力的途径上的中心科学问题。表征维持和调节干细胞群体的细胞信号将导致对活生物体控制生长和发育的原理的新认识，并导致开发在健康应用中利用干细胞的新技术，包括组织和器官再生。拟议的研究，通过表征在模型系统中调节干细胞增殖，分化和规范的因素，将揭示干细胞生态位组织的新原则。这项研究旨在回答干细胞生物学中尚未回答的核心问题：细胞间通讯指导干细胞群体中细胞行为的机制是什么？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，开花植物拟南芥的茎顶端分生组织（SAM）将被用作模式系统。两个关键的信号通路，以及它们之间的相互作用，将被研究：CLAVATA-WUSCHEL肽信号通路和激素细胞分裂素信号通路。实现该提案目标的结果将是对干细胞小生境的新水平的理解，以及反馈，信号传导和局部细胞类型反应的原理，使它们能够作为永久和受调节的细胞库用于组织的创建。这些实验将使我们对植物的发育和干细胞调控的理解达到一个新的水平;因此，对植物和动物的干细胞调控原理有了更全面的理解和比较。每个目标都将使用非侵入性的活体成像技术，这些技术在植物中特别有效，因为它们的干细胞靠近表面，转基因报告基因，以及改变干细胞行为调节的大量突变。第一个目标的目标是充分表征的机制，通过该机制，激素细胞分裂素水平的改变影响SAM干细胞生态位的不同领域，既直接，通过调节肽信号传导途径，并通过激素信号传导系统自身的多重反馈。第二个目标是一个系统的方法来表征细胞分裂素信号通路从受体到反应调节转录。使用新型TRAP-seq和INTACT方法，将以细胞和分子分辨率对细胞分裂素靶基因进行表征。第三个目标是一个公正的酵母单杂交筛选，以确定细胞分裂素信号的转录调节因子，和细胞分裂素生物合成基因。第四个也是最后一个目标是使用通过这些方法生成的数据来参数化封装系统中复杂反馈的计算模型，以测试细胞间通信调节SAM干细胞生态位的机制的新假设。