Specification, Molecular Control and Niche Functions of the Hair Follicle Mesenchyme

毛囊间充质的规格、分子控制和利基功能

• 批准号: 10677864
• 负责人: Michael Rendl
• 金额: $ 61.09万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-15 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10677864
• 关键词: Ablation; Biological Assay; Calcium; Calcium Signaling; Cell Communication; Cells; Cessation of life; Color; Contracts; Data; Dedications; Dermal; Development; Endothelin; Endothelin-1; Epithelium; Funding; Future; Genetic; Germ; Goals; Growth; Hair; Hair follicle structure; Hair shaft structure; Image; Immunofluorescence Immunologic; In Situ Hybridization; In Vitro; Knock-out; Knowledge; Ligands; Location; Maps; Mesenchymal; Mesenchyme; Methods; Molecular; Mus; Muscle Contraction; Natural regeneration; Pathway interactions; Peptides; Phase; Physiological; Population; Positioning Attribute; Process; Proliferating; Regulation; Regulatory Pathway; Reporter; Rest; Role; Sarcoplasmic Reticulum; Science; Signal Pathway; Signal Transduction; Skin; Smooth Muscle; Specific qualifier value; Study models; System; Testing; Vasoconstrictor Agents; Visualization; Work; base; epithelial stem cell; genetic signature; germline stem cells; hair regeneration; in vivo; inhibitor; intravital imaging; member; meter; molecular dynamics; novel; pharmacologic; progenitor; receptor; regenerative therapy; rho; small molecule inhibitor; stem cells; tongue papilla; transcriptome; two photon microscopy; vasoconstriction; voltage

Project Summary During the hair cycle, growing hair follicles (HF) regress in a phase marked by progenitor death and follicle remodeling (catagen), before a rest period (telogen) and new hair growth (anagen). Signals from the dermal papilla (DP) – a key signaling center – regulate progenitor proliferation and differentiation in the bulb of growing HFs, and induce bulge/germ stem cells (SC) to regenerate fully growing HFs. During catagen regression, the DP needs to relocate from the base of growing HFs to the SC reservoir in the upper HF, traversing the skin several hundred micrometers. How this is accomplished has been unknown for decades. In the first funding period, we have uncovered that the follicle-lining dermal sheath (DS) is a smooth muscle that contracts to physically relocate the DP to reach its essential SC-adjacent position. The dynamic molecular changes that occur in adjacent progenitors and the DS and whether epithelial-mesenchymal crosstalk between them regulates contraction is unknown. Exploring our DS and several other gene signatures suggested an intriguing role of endothelin signaling, a well-known vasoconstriction regulatory pathway, in controlling DS contraction. With several established and newly developed functional assays and novel genetic DS targeting, we have now established the conditions for exploring the dynamic expression of endothelin ligand, receptor and other pathway members in progenitors, DS and DP during both growth and regression; for investigating the functional role(s) of progenitor-derived endothelin in signaling and activating contraction; and for dissecting the downstream pathway mechanism(s). Overall, we will rigorously test the hypothesis that follicle progenitors and the DS engage in epithelial-mesenchymal crosstalk crucial for regulating DS contraction and hair cycle regression. We will precisely map expression localization and timing of key endothelin signaling pathway members through detailed in situ hybridization and immunofluorescence analyses. We will further purify DS and progenitors with novel multicolor isolation methods from growing and regressing follicles and analyze their transcriptomes to define potential signaling crosstalk in general and all components of the endothelin pathway system in particular. We will pharmacologically activate and block endothelin signaling activation in isolated DS cells and microdissected follicles, and determine functional DS contraction in our recently established in vitro and ex vivo live imaging assays. We will then explore the consequences of contraction inhibition in vivo and directly visualize contraction inhibition with intravital imaging. We will perform timed genetic receptor and ligand ablations and assess the impact on follicle regression. Finally, we will define the spatial and temporal calcium signaling dynamics downstream of endothelin pathway activation using calcium reporter mice and activators and inhibitors of Ca2+ channels as well as of the PLC/PKC activation to dissect the major endothelin signaling pathway branches that operate to activate DS contraction. With this work will define a key physiological function of progenitor-DS interaction, which may be useful for hair regeneration approaches, including manipulating follicle regression.

项目摘要 在头发周期中，生长毛囊（HF）在以祖细胞死亡和卵泡标记的相位回归 在休息时间（端基）和新头发生长（Anagen）之前，重塑（catagen）。皮肤的信号 乳头（DP） - 一个关键信号中心 - 调节祖细胞增殖和分化的范围 HFS，并诱导隆起/生殖干细胞（SC）再生全部生长的HF。在Catagen回归期间， DP需要从增长的HF的底部转移到上HF的SC储层，从而穿越皮肤 数百微米。几十年来，如何实现这一目标一直未知。在第一个资金中 时期，我们发现了叶叶衬皮肤鞘（DS）是一种平滑肌，收缩到 物理重新安置DP以达到其必不可少的SCADJACACEST位置。发生的动态分子变化 在相邻的祖细胞和DS中，以及它们之间的上皮 - 间质串扰是否在调节 收缩是未知的。探索我们的DS和其他几个基因特征表明 内皮素信号传导是一种众所周知的血管收缩调节途径，可控制DS收缩。和 几种已建立的，新开发的功能测定和新颖的遗传DS靶向，我​​们现在已经有了 建立了探索内皮素配体，接收器和其他途径的动态表达的条件 祖先，DS和DP的成员在生长和回归过程中；用于研究功能作用 祖细胞来源的内皮素在信号传导和激活合同中；并为下游解剖 途径机制。总体而言，我们将严格检验叶祖细胞和DS参与的假设 在上皮 - 间质串扰中，对于调节DS收缩和头发周期回归至关重要。我们将 精确映射表达式的定位和密钥内皮素信号通路成员的时间安排和时间通过详细 原位杂交和免疫荧光分析。我们将用新颖 通过生长和回归卵泡的多色隔离方法并分析其转录组以定义 通常，尤其是内皮素途径系统的所有组件，潜在的信号串扰。我们 将在孤立的DS细胞中物理激活并阻止内皮素信号传导激活并微解析 卵泡，并确定我们最近建立的体外和离体实时成像中功能性DS收缩 测定。然后，我们将探索体内收缩抑制的后果，并直接可视化收缩 用插入成像抑制。我们将执行定时的遗传接收器和配体消融，并评估 对植物回归的影响。最后，我们将定义空间和临时钙信号传导动力学 内皮素途径的下游使用钙报告小鼠和激活剂和Ca2+的抑制剂激活 通道以及PLC/PKC激活，以剖析主要的内皮素信号通路分支 运行以激活DS收缩。通过这项工作，将定义祖细胞DS的关键生理功能 相互作用，这对于头发再生方法可能有用，包括操纵叶片回归。