Extreme cell growth in support of stem cell proliferation and niche exit

极端的细胞生长支持干细胞增殖和利基退出

• 批准号: 10501818
• 负责人: Kacy Lynn Gordon
• 金额: $ 38.22万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10501818
• 关键词: Address; Adhesions; Adult; Animals; Area; Behavior; Biological Models; Cadherins; Caenorhabditis elegans; Candidate Disease Gene; Cell Fate Control; Cell Proliferation; Cell division; Cells; Cellular Structures; Complex; Cues; Development; Embryo; Genes; Germ Cells; Germ Lines; Goals; Gonadal structure; Growth; Health; Human; Larva; Life; Maintenance; Mediating; Microscopic; Modeling; Molecular; Organism; Pathway interactions; Proliferating; RNA Interference; Regulation; Research; Somatic Cell; Structure; System; Time; Tissues; Undifferentiated; Work; cell growth; daughter cell; egg; follow-up; genetic analysis; genetic manipulation; germline stem cells; imaging study; in vivo imaging; insight; loss of function; neglect; next generation; pandemic disease; programs; self-renewal; sperm cell; stem cell division; stem cell fate; stem cell model; stem cell niche; stem cell population; stem cell proliferation; stem cells; success; transcriptome sequencing

K. Gordon, UNC R35 Abstract The specification and robust maintenance of the germ line stem cells and their differentiated descendants that form gametes are essential to the success of an organismal lineage. Stem cell niches are primary regulators of stem cell fate, which is characterized by continuous self-renewal with the capability of differentiation. Therefore the structure of stem cell niches—which often have extensive cellular contacts with their supported stem cell populations that must be broken by daughter cells that go on to differentiate—appear crucial for the regulation of the cell fate decision. Such contacts are shared in a variety of stem cell niches, but studies relating niche structure to function lag behind genetic analysis of stem cell regulation. Stem cell niches lie deep in tissues, making them difficult to observe, and stem cell divisions are stochastic. This proposal avoids these challenges by studying the germ line stem cell niche of C. elegans, an animal that is suited to multiplex in vivo imaging. The overall goal for the research program is to discover how undifferentiated germ stem cells receive cues from their micro-environment to stimulate proliferation and the cell fate switch to gamete differentiation, and how the dynamic cell structures supporting germ stem cells form. Conserved proliferation and cell growth pathways are relevant to human health. Pursuit of these questions will lead to insights that, like other findings made in this canonical stem cell niche model, may be broadly applicable to other stem cell systems. Overview of research and goals for the next five years: The Gordon Lab opened at UNC just before the pandemic began. It pursues key questions like: How do the stem cell niche and gonad sheath cells grow and internally partition themselves to interact appropriately with germ cells at different steps of the differentiation program? Both the niche cell and sheath undergo substantial growth and transformation during development. Both somatic cells will be genetically manipulated to determine if effects on germ cell proliferation are mediated by growth and partitioning of these regulatory cells. Cell-specific RNAi strains will be used to screen for genes resulting in diminished Sh1 growth and germ cell proliferation. What molecular mechanisms underlie oriented cell divisions at the niche boundary and asymmetrical cell fate acquisition? Spindle orientation has been studied in great detail in early C. elegans embryos, but it was not known that divisions in proliferating germ cells were oriented. Adhesion between the niche and germ cells was a neglected area of inquiry until recent findings implicated cadherin complexes—which orient spindles in the embryo—in the dramatic wrapping behavior of the niche around the stem cells. How does the stem cell niche mature from larvae to adults? RNA- seq of niche cells across the larva/adult transition will identify candidate genes that are correlated with the transition from a migratory niche during gonad growth to a stationary, mature adult niche. These and known genes will be investigated by tagging and loss of function analysis in live-imaging studies of the transition. Together this work will address arising and long-standing questions about a classical stem cell model system.

K.戈登，UNC R35 摘要 生殖系干细胞及其分化后代的规范和稳健维护 配子的形成对于有机体谱系的成功至关重要。干细胞生态位是主要调节因子 干细胞命运，其特点是不断自我更新并具有分化能力。所以 干细胞巢的结构——通常与其支持的干细胞有广泛的细胞接触 必须被继续分化的子细胞破坏的群体——对于调节似乎至关重要 细胞命运的决定。这种接触在各种干细胞生态位中共享，但与生态位相关的研究 结构到功能滞后于干细胞调控的遗传分析。干细胞巢位于组织深处， 这使得它们难以观察，而且干细胞分裂是随机的。该提案避免了这些挑战 通过研究秀丽隐杆线虫（一种适合多重体内成像的动物）的生殖系干细胞生态位。 该研究项目的总体目标是发现未分化的生殖干细胞如何接收线索 从微环境中刺激增殖和细胞命运转变为配子分化，以及 支持生殖干细胞的动态细胞结构如何形成。保守增殖和细胞生长 途径与人类健康相关。与其他发现一样，对这些问题的追求将带来一些见解 在这个典型的干细胞生态位模型中制作的，可能广泛适用于其他干细胞系统。 未来五年的研究概述和目标：戈登实验室在北卡罗来纳大学成立之前 大流行开始了。它追求以下关键问题：干细胞生态位和性腺鞘细胞如何生长和 内部划分自身以在分化的不同步骤与生殖细胞适当地相互作用 程序？在发育过程中，生态位细胞和鞘都经历大量的生长和转化。 两种体细胞都将被进行基因操作，以确定是否介导对生殖细胞增殖的影响 通过这些调节细胞的生长和分配。细胞特异性RNAi菌株将用于筛选基因 导致Sh1生长和生殖细胞增殖减少。定向的分子机制是什么 生态位边界处的细胞分裂和不对称的细胞命运获取？主轴方向已 在早期秀丽隐杆线虫胚胎中进行了详细研究，但人们不知道增殖细菌的分裂 细胞是定向的。直到最近，生态位和生殖细胞之间的粘附一直是一个被忽视的研究领域 研究结果表明钙粘蛋白复合物（它在胚胎中定向纺锤体）与戏剧性的包裹有关 干细胞周围生态位的行为。干细胞生态位如何从幼虫成熟到成虫？ RNA- 跨越幼虫/成虫过渡的利基细胞的序列将识别与 从性腺生长期间的迁移生态位转变为固定的、成熟的成体生态位。这些和已知的 在转变的实时成像研究中，将通过标记和功能丧失分析来研究基因。 这项工作将共同解决有关经典干细胞模型系统的新问题和长期存在的问题。