Molecular Mechanisms of Leydig Cell Regeneration

间质细胞再生的分子机制

• 批准号: 10454800
• 负责人: Jasmin LaKia Jeffery
• 金额: $ 4.68万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10454800
• 关键词: Ablation; Adult; Age; Aging; Alkanesulfonates; Androgens; Automobile Driving; Biology; Candidate Disease Gene; Cell Cycle; Cell Death; Cell Proliferation; Cells; Characteristics; Chemicals; Cre driver; Cytotoxic agent; Data; Development; Ethane; Gene Expression Profile; Gene Expression Profiling; Genes; Genetic; Germ Cells; Goals; In Vitro; Injury; Interphase Cell; Male Infertility; Malignant Neoplasms; Modeling; Molecular; Monitor; Mus; Natural regeneration; Organ; Organism; Pathway interactions; Personal Satisfaction; Pharmacology; Physiological; Population; Process; Rattus; Regenerative research; Role; Signal Pathway; Signal Transduction; Somatic Cell; Source; Supporting Cell; System; Testing; Testis; Tissue Model; Tissues; Work; candidate marker; cell regeneration; cell type; differential expression; extracellular; improved; in vivo regeneration; inhibitor; injured; interest; leydig interstitial cell; male; male fertility; male health; men; mouse genetics; novel; precursor cell; progenitor; regeneration model; regenerative; regenerative cell; repaired; response; response to injury; self-renewal; single-cell RNA sequencing; small molecule; sperm cell; stem cells; tissue regeneration; tool; transcriptome; transcriptome sequencing; transcriptomics

Cells lost to normal wear and tear in many adult tissues are replaced with the activity of stem cells. In response to injury, however, cells can use entirely different strategies to repair and regenerate tissues. Injured tissues can be regenerated through the activation of stem cells or from progenitor cells that, unlike stem cells, are incapable of asymmetric division and self-renewal. The dramatic cellular changes that occur during regeneration are thought to arise from altered signaling in the tissue microenvironment, or niche, but the mechanisms regulating regeneration are largely unknown. A classical model of regeneration after injury is the adult rat testis. In the testis, somatic cells create a microenvironment that contributes to the germ cell niche. Critical somatic support cells include Leydig cells, the major androgen producing cells in males, which are required for male health and fertility. Although Leydig cells are a quiescent cell type, and not thought to divide under normal conditions, they are chemically ablated by ethane dimethane sulfonate (EDS). Several weeks after chemical ablation, new Leydig cells repopulate the testis. The mechanism of Leydig cell regeneration and the progenitors from which they arise remain poorly understood, partially due to the lack of genetic tools available in rats. In vitro work has hinted at candidate markers that may identify progenitors of Leydig cell regeneration. The goal of this project is to determine the cellular mechanism and molecular mechanism of Leydig cell regeneration. Mouse genetics make it possible to interrogate the cellular mechanism of regeneration by use of an inducible genetic lineage tracing system. In preliminary data, a subset of somatic testis interstitial cells trace into new Leydig cells after ablation in mice. We will continue using this model to determine the both identity of the progenitor cells and whether this cell type is self-renewing. We will also determine the molecular mechanisms driving regeneration with the use of sc-RNA sequencing before, during, and after regeneration. Candidate genes implicated in signaling and Leydig cell development that are differentially expressed in regenerating cells will be tested for functional roles during regeneration using small molecule pathway inhibitors and available genetic tools. While small molecules are an accessible way to gain crude information about whether a signaling pathway is involved, sc-RNA sequencing will illuminate exactly which cells produce signals that initiate the progenitor response. Determining the cellular and molecular mechanisms of Leydig cell regeneration will significantly contribute to the understanding of adult tissue regeneration in vivo with broader implications for male fertility and health.

许多成体组织中因正常磨损而丢失的细胞被具有活性的干细胞所取代。作为回应 然而，对于损伤，细胞可以使用完全不同的策略来修复和再生组织。受伤的组织 可以通过干细胞或祖细胞的激活来再生，与干细胞不同，祖细胞是 不能不对称分裂和自我更新。期间发生的剧烈细胞变化 再生被认为是由组织微环境或生态位中的信号改变引起的，但 调节再生的机制在很大程度上是未知的。损伤后再生的经典模型是 成年大鼠睾丸。在睾丸中，体细胞创造了一个有助于生殖细胞生态位的微环境。 关键的体细胞支持细胞包括 Leydig 细胞，它是男性中主要产生雄激素的细胞， 男性健康和生育能力所必需的。尽管间质细胞是一种静止细胞类型，并且不被认为可以分裂 在正常情况下，它们会被二甲磺酸乙烷（EDS）化学消融。几周 化学消融后，新的间质细胞重新填充睾丸。 Leydig细胞再生机制及 它们产生的祖先仍然知之甚少，部分原因是缺乏遗传工具 可用于大鼠。体外工作暗示了可能识别间质细胞祖细胞的候选标记 再生。该项目的目标是确定细胞机制和分子机制 间质细胞再生。小鼠遗传学使得探究细胞机制成为可能 通过使用诱导遗传谱系追踪系统进行再生。在初步数据中，体细胞的一个子集 小鼠睾丸间质细胞消融后可追踪到新的 Leydig 细胞。我们将继续使用这个模型 确定祖细胞的身份以及该细胞类型是否具有自我更新能力。我们还将 在之前、期间、期间使用 sc-RNA 测序确定驱动再生的分子机制 以及再生后。与信号传导和间质细胞发育有关的候选基因 再生细胞中差异表达的细胞将使用小样本测试再生过程中的功能作用。 分子途径抑制剂和可用的遗传工具。虽然小分子是一种容易获得的方法 有关信号通路是否参与的粗略信息，sc-RNA 测序将准确阐明 哪些细胞产生启动祖细胞反应的信号。确定细胞和分子 间质细胞再生机制将极大地有助于理解成体组织 体内再生对男性生育能力和健康具有更广泛的影响。