Molecular Mechanisms of Regeneration Termination

再生终止的分子机制

• 批准号: 10408258
• 负责人: Hiroshi Nakato
• 金额: $ 32.94万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-01 至 2026-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10408258
• 关键词: Actins; Activins; Address; Affect; Bacterial Infections; Biological Models; Cells; Complex; Data; Drosophila genus; Dystroglycan; Dystrophin; ECM receptor; Epithelial; Extracellular Matrix; Failure; Filopodia; Foundations; Future; Gene Silencing; Genes; Genetic; Glycoproteins; Heparan Sulfate Proteoglycan; High-Risk Cancer; Homeostasis; Integrins; Intestines; Knowledge; Link; Mediating; Membrane; Messenger RNA; MicroRNAs; Midgut; Mitotic Activity; Modeling; Molecular; Natural regeneration; Nature; Order Coleoptera; Organ Size; Papio; Pathway interactions; Phase; Process; Role; Septate; Signal Transduction; Stem Cell Development; Testing; Tissues; Type I Activin Receptors; design; gastrointestinal system; gliotactin; helicase; member; regenerative tissue; response; stem cell function; stem cell model; stem cell proliferation; stem cell therapy; stem cells; syndecan; targeted cancer therapy; tissue regeneration; tissue repair; tool; transcriptome sequencing; tumor

Project Summary The molecular mechanisms by which stem cell proliferation is precisely controlled during the course of regeneration are poorly understood. Namely, how a damaged tissue senses when to terminate the regeneration process, inactivates stem cell mitotic activity, and organizes ECM integrity remain fundamental unanswered questions. Uncontrolled proliferation of stem cells in regenerative tissues can result in tumor formation. The Drosophila midgut intestinal stem cell (ISC) has recently emerged as an attractive model system to study tissue homeostasis and regeneration. This is due to striking similarities in genetic control and cellular composition between the Drosophila and mammalian digestive systems, and powerful genetic tools available in this model. Importantly, Drosophila ISC proliferation is promoted in response to tissue damage to stimulate tissue repair. Using this model system, a number of studies have been conducted to reveal the pathways that activate ISC proliferation. Despite a wealth of knowledge on the activation of proliferative capacity of stem cells, it is largely unknown how the tissue properly down-regulates stem cell proliferation at the end of regeneration and how this process is linked to epithelial remodeling. We recently established the Drosophila ISCs as an excellent model to study the molecular basis for regeneration termination. Using RNA-seq, we identified sets of genes and pathways that are up/down-regulated at different phases of regeneration. Among these, we found that dMOV10, a component of the microRNA (miRNA) gene silencing complex, is required for the proper termination of the regeneration process. Further analyses identified direct target mRNAs of dMOV10-containing miRISC, including baboon (the Type I receptor of activin signaling) and two major non- integrin ECM receptors, Syndecan (a transmembrane heparan sulfate proteoglycan) and Dystroglycan (an integral membrane component of the dystrophin-glycoprotein complex). In addition to the identification of dMOV10 as a termination stage-specific gene, this same RNA-seq analysis showed that key components for septate junctions, and actin regulators are specifically upregulated during regeneration and return to normal level at a late stage. In this proposal, we will define these key molecules in stem cell inactivation and ECM remodeling at the termination stage of Drosophila midgut regeneration through the following Specific Aims. Aim 1. Determine the role of septate junction components in midgut regeneration. Aim 2. Define the role of Sdc and Dg in ECM remodeling. Aim 3. Define the global landscape of the miRNA-mediated network.

项目摘要 在过程中精确控制干细胞增殖的分子机制 再生知之甚少。也就是说，损坏的组织何时终止 再生过程，使干细胞有丝分裂活性失活，并组织ECM的完整性仍然是基本的 未解决的问题。再生组织中干细胞的不受控制的增殖会导致肿瘤 形成。果蝇中肠干干细胞（ISC）最近出现了作为有吸引力的模型 研究组织稳态和再生的系统。这是由于遗传控制中的相似之处 果蝇和哺乳动物消化系统之间的细胞组成以及强大的遗传 此模型中可用的工具。重要的是，果蝇ISC增殖是响应组织而促进的 损害刺激组织修复。使用此模型系统，已经进行了许多研究 揭示激活ISC增殖的途径。 尽管对干细胞增殖能力的激活有丰富的知识，但它在很大程度上是 未知组织如何在再生结束时正确下调干细胞增殖以及如何 此过程与上皮重塑有关。我们最近将果蝇ISC确定为出色 研究再生终止分子基础的模型。使用RNA-Seq，我们确定了 在再生的不同阶段上向上/下调的基因和途径。其中，我们 发现DMOV10是microRNA（miRNA）基因沉默复合物的成分，需要 适当终止再生过程。进一步分析确定了直接目标mRNA 含DMOV10的Mirisc，包括狒狒（激活素信号的I型受体）和两个主要的非 - 整联蛋白ECM受体，syndecan（跨膜硫酸盐蛋白聚糖）和dystroglycan（一个 肌营养不良蛋白糖蛋白复合物的整体膜成分）。除了识别 DMOV10作为终止阶段特异性基因，相同的RNA-seq分析表明，关键成分 对于分隔连接处，在再生期间特别上调了肌动蛋白调节剂 晚期正常水平。 在此提案中，我们将在干细胞灭活和ECM重塑中定义这些关键分子 果蝇中肠再生的终止阶段通过以下特定目的。目标1。 确定分隔连接组件在中肠再生中的作用。目标2。定义SDC的作用 和ECM重塑中的DG。目标3。定义miRNA介导的网络的全球景观。