Dermal Papilla Regulation and Function for Stem Cell Activation in the Hair Cycle

毛乳头对毛发周期中干细胞激活的调节和功能

• 批准号: 10132732
• 负责人: Michael Rendl
• 金额: $ 47.38万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10132732
• 关键词: Ablation; Adipocytes; Adult; Biological Models; Biological Process; Cell Separation; Cells; Cre driver; Data; Dermal; Dermis; Development; Embryo; Event; Fibroblasts; Future; Gene Expression; Gene Expression Profiling; Gene Expression Regulation; Gene Targeting; Genes; Genetic; Germ; Goals; Hair; Hair follicle structure; Injections; Instruction; Investigation; Knowledge; Label; Ligands; Link; Mediating; Mesenchymal; Mesenchyme; Methods; Molecular; Molecular Analysis; Molecular Profiling; Mus; Natural regeneration; Periodicity; Physiologic pulse; Platelet-Derived Growth Factor; Platelet-Derived Growth Factor alpha Receptor; Play; Publishing; Regulation; Resolution; Rest; Role; Signal Pathway; Signal Transduction; Skin; Study models; Technology; Testing; Tissue Engineering; Work; adult stem cell; cell type; cytokine; experimental study; gene function; genetic signature; germline stem cells; hair regeneration; improved; insight; novel; regenerative therapy; stem cell function; stem cells; therapy development; tongue papilla; tool

Project Summary The hair follicle (HF) cycle is an excellent model for studying adult stem cell (SC) regulation by the microenvironment or niche, as it involves cyclical bouts of destruction (catagen), rest (telogen) and regrowth (anagen). Signals from the dermal papilla (DP) – a cluster of mesenchymal HF cells – are thought to induce a switch from a resting to an activated state in bulge/germ SCs during the telogen-to-anagen transition of the hair cycle. However, due to the lack of direct genetic tools for robust, inducible targeting of the telogen DP for gene ablation, the functional evidence for a role of the DP in SC activation is largely indirect. We also know little about the long-term fate and potential of the adult DP and its lineage relationships to the dermal sheath and fibroblasts. Finally, the precise molecular repertoire of the adult DP during the hair cycle has remained poorly defined, due to the limitations of DP isolation and gene expression analysis in previous studies. We recently established genetic labeling strategies for the specific isolation and molecular characterization of embryonic DP precursors and the DP from growing HFs, making it possible to identify their molecular signatures. We then developed embryonic DP-specific gene targeting tools and explored the role of DP signature genes during HF formation. We have now further established the conditions for the robust and inducible genetic targeting of the telogen DP, thus enabling exploration of the cellular turnover and clonal lineage relationships in the DP along with investigation into the molecular mechanisms underlying DP instruction of HF activation during the telogen- to-anagen transition. In these studies, we will rigorously test the hypothesis that the telogen DP serves as a SC-activating niche during the hair cycle. We will establish Crabp1 as the first robust, inducible genetic driver for Cre-mediated targeting of the telogen DP. We will then use Crabp1iCreER mice to determine, with spatial and temporal precision, the cellular turnover of the DP and its lineage relationship to the neighboring dermal sheath and the skin mesenchyme, through genetic fate mapping and pulse-chase label retention experiments, gaining insight into DP identity and lineage potential. We will use our novel driver to ablate PDGFRα and PDGFRβ in the telogen DP, assess SC activation status in the bulge/germ, the impact of the loss of PDGF signaling on hair regeneration, and decipher the molecular mechanisms underlying the PDGF signaling-driven DP functions regulating SC activation. We will isolate pure DP, bulge/germ SCs and related cell types at key hair cycle stages, and systematically define their molecular signatures throughout the hair cycle, with unprecedented cellular resolution and sensitivity of gene expression discovery. We will then investigate the functional role of Nr3c1 and other newly identified DP signature genes, by gene ablation with Crabp1iCreER in the telogen DP. With this work, we will greatly expand our knowledge of SC regulation by these niche cells, which will be essential for the development of treatments involving the regeneration of functional skin, including HFs.

项目摘要 毛囊（HF）周期是研究成人干细胞（SC）调节的绝佳模型 微环境或利基市场，因为它涉及破坏（Catagen），休息（Telogen）和改革 （Anagen）。来自真皮乳头（DP）的信号 - 间充质HF细胞簇 - 被认为会诱导A 在链球菌对 - 远离头发过渡期间，从静止状态转到激活状态 循环。但是，由于缺乏可鲁棒的直接遗传工具，因此诱导型基因的链托型靶向 消融，DP在SC激活中作用的功能证据在很大程度上是间接的。我们也不知道 关于成人DP的长期命运和潜力及其与皮肤护套的谱系关系 成纤维细胞。最后，在头发周期中，成年DP的精确分子曲目仍然很差 在先前的研究中，由于DP隔离和基因表达分析的局限性而定义。我们最近 建立的遗传标记策略，用于胚胎的特定分离和分子表征 DP前体和DP生长的HFS，使其可以识别其分子特征。然后我们 开发的胚胎DP特异性基因靶向工具，并探索了DP签名基因在HF中的作用 形成。现在，我们已经进一步确定了鲁棒和诱导的遗传靶向的条件 Telogen DP，因此可以探索DP沿DP中的细胞更新和克隆谱系关系 通过投资对端基期间HF激活的DP教学的分子机制 to-anagen过渡。在这些研究中，我们将严格检验端基DP作为一个的假设 在头发周期中激活SC激活利基市场。我们将建立CrabP1作为第一个强大的，可诱导的遗传驱动器 用于CRE介导的端机DP的靶向。然后，我们将使用crabp1icreer小鼠通过空间和 暂时的精度，DP的细胞周转及其与相邻皮肤鞘的谱系关系 以及通过遗传脂肪图和脉搏练习标签保留实验的皮肤间充质，获得 深入了解DP身份和谱系潜力。我们将使用新型驱动器在pdgfrα和pDGFRβ中使用 Telogen DP，评估凸起/胚芽中的SC激活状态，PDGF信号丢失对 头发再生，并破译PDGF信号驱动的DP功能的分子机制 调节SC激活。我们将在关键头发周期中隔离纯DP，凸起/细菌SC和相关细胞类型 阶段，并在整个头发周期中系统地定义其分子特征 基因表达发现的细胞分辨率和灵敏度。然后，我们将研究 NR3C1和其他新鉴定的DP签名基因，通过基因在Telogen DP中与Crabp1icreer消融。 通过这项工作，我们将通过这些利基细胞大大扩展我们对SC调节的了解，这将是 涉及功能性皮肤的再生至关重要的，包括HFS。