The function of germ granules in maintaining pluripotency in the C. elegans germline

胚芽颗粒在维持线虫种系多能性中的功能

• 批准号: 10371247
• 负责人: Dustin Lynn Updike
• 金额: $ 33.2万
• 依托单位: MOUNT DESERT ISLAND BIOLOGICAL LAB
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10371247
• 关键词: 26S proteasome; Affinity; Alleles; Alpha Granule; Animals; Back; Biogenesis; CRISPR/Cas technology; Caenorhabditis elegans; Cataract; Cell Nucleus; Complex; Core Protein; Cytoplasm; Cytoplasmic Granules; DNA; Data; Development; Distributional Activity; Elements; Ensure; Environment; Epigenetic Process; Equilibrium; Fertility; Fertility Disorders; Gene Expression; Generations; Genes; Genetic Transcription; Germ; Germ Cells; Goals; Heritability; Homologous Gene; Human; Individual; Licensing; Malignant Neoplasms; Maps; Mediating; Messenger RNA; Modeling; Molecular; Mutation; Names; Natural regeneration; Nematoda; Nuclear; Nuclear Pore; Peptide Initiation Factors; Phase; Polyribosomes; Proteins; Proteomics; RNA; RNA Binding; RNA Helicase; Reporter; Reporting; Research; Ribonucleoproteins; Ribosomes; Role; Safety; Small RNA; Somatic Cell; Specificity; Spermatogenesis; Sterility; Tertiary Protein Structure; Testing; Time; Transcript; Translating; Translations; cancer testis antigen; cell type; developmental plasticity; healing; insight; male; multicatalytic endopeptidase complex; mutant; neuronal cell body; novel; pluripotency; prevent; protein degradation; protein expression; scaffold; sperm cell; synergism; therapeutic target; tissue regeneration; tumor; tumorigenesis

Project Summary Germ cells and somatic cells from an individual carry identical copies of DNA; yet, only germ cells have the potential to give rise to all the cell types of each subsequent generation. This suggests that epigenetic factors confer pluripotent and immortal potential to germ cells. Some of these epigenetic factors are exclusive to the germ cell cytoplasm, and in certain cases their presence is enough to reprogram somatic nuclei to restore pluripotency and immortal potential. A distinguishing feature of germ cell cytoplasm are germ granules. Germ granules are a phase-separated, heterogeneous mix of RNA and protein that have been observed in the germline of most animals. Because core germ-granule composition is conserved from nematodes to humans, the genetically tractable model C. elegans is used to study how germ granules function to regulate the pluripotent and immortal potential of germ cells. Germ granules extend the environment of the nuclear pore into the cytoplasm, where they serve as a safety next to ensure that nascent transcripts coming from the nucleus are licensed for germline expression. Depletion of germ granules in C. elegans causes sterility and germ-to-soma transformation. The long-term objectives of this research are to understand how germ granules regulate cellular pluripotency and their potential to be manipulated to induce pluripotency when it is needed (e.g. regeneration) or shut it off when it is not (e.g. cancer). A conserved core of germ-granule proteins act as multipotency factors, and are often repurposed in the soma during development, tissue regeneration, and tumorigenesis. This core consists of Vasa DEAD-box RNA helicases, small RNA binding Argonaute proteins, and LOTUS-Tudor domain proteins that interface and stimulate Vasa and Argonaute activity. The role of these multipotency factors during tumorigenesis, and whether they contribute to the phenomenon of cancer/testis (CT) antigen expression in various tumors has not been explored. Here, C. elegans is used to understand how these core proteins are expressed and distributed, what they interact with, and their role in fertility and developmental plasticity. The specific aims in this proposal look at 1) the role of germ granules in protein expression and turnover, primarily focusing on the novel interaction of GLH/Vasa with PCI scaffolding complexes, 2) how GLH promotes the differential translation of spermatogenic transcripts, and 3) how GLH and a new LOTUS-Tudor protein called LOTR-1 cooperates to maintain germline integrity. If successful, these findings will reveal novel ways to manipulate cellular pluripotency and expose the potential therapeutic targets that directly regulate the cytoplasm instead of nuclear gene expression networks.

项目摘要 来自个体的生殖细胞和体细胞携带相同的DNA拷贝；但是，只有生殖细胞具有 产生每种后期的所有细胞类型的潜力。这表明表观遗传因素 赋予生殖细胞多能和不朽的潜力。这些表观遗传因素中的一些是独有的 生殖细胞细胞质，在某些情况下，它们的存在足以重新编程体细胞核以恢复 多能性和不朽的潜力。生殖细胞细胞质的显着特征是生殖颗粒。胚芽 颗粒是在种系中观察到的RNA和蛋白质的相分开的异质混合物 大多数动物。由于核菌粒颗粒组成是从线虫到人类的保守的，所以 遗传上可牵引的模型C.秀丽隐杆线虫用于研究生殖颗粒如何调节多能 生殖细胞的不朽潜力。细菌颗粒将核孔的环境扩展到 细胞质，在该细胞质中作为安全性，以确保来自核的新生转录本为 获得种系表达的许可。秀丽隐杆线虫中的细菌颗粒的耗竭会导致不育和细菌至疾病 转型。这项研究的长期目标是了解细菌颗粒如何调节细胞 多能及其被操纵的潜力在需要时引起多能性（例如，再生） 或在没有时将其关闭（例如癌症）。 生殖颗粒蛋白的保守核心是多能量因素，通常在 在发育，组织再生和肿瘤发生过程中的躯体。该核心由VASA Dead-Box RNA组成 解旋酶，小的RNA结合Argonaute蛋白以及插头和接口的莲育域蛋白 刺激Vasa和Argonaute活动。这些多重因素在肿瘤发生过程中的作用，以及是否是否 它们有助于各种肿瘤中癌症/睾丸（CT）抗原表达的现象 探索。在这里，秀丽隐杆线虫用于了解这些核心蛋白如何表达和分发，什么 它们与生育和发育可塑性中的作用及其作用。此提案外观的具体目的 在1）生殖颗粒在蛋白质表达和周转中的作用，主要集中于新的相互作用 具有PCI脚手架配合物的GLH/VASA，2）GLH如何促进精子的差分翻译 成绩单，以及3）GLH和新的Lotus-Tudor蛋白如何称为Lotr-1来维持种系 正直。如果成功，这些发现将揭示操纵细胞多能性并暴露的新方法 直接调节细胞质而不是核基因表达网络的潜在治疗靶标。