Specification of Dermal Papilla Cell Fate in the Hair Follicle Stem Cell Niche

毛囊干细胞微环境中真皮乳头细胞命运的规范

• 批准号: 8034288
• 负责人: Michael Rendl
• 金额: $ 36.32万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-01 至 2015-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8034288
• 关键词: Ablation; Biological Assay; Biological Models; Bone Marrow; Brain; Cells; Dermal; Development; Embryonic Development; Epithelial; Fibroblasts; Future; Gene Expression; Gene Targeting; Genes; Genetic; Goals; Growth; Hair; Hair follicle structure; Homeostasis; Hybrids; In Vitro; Intestines; Invertebrates; Knock-out; Knowledge; Lead; Mesenchymal; Methods; Modeling; Molecular; Molecular Profiling; Morphogenesis; Mus; Natural regeneration; Patients; Process; Proliferating; Regulation; Rest; Signal Transduction; Skin; Skin Tissue; Specific qualifier value; Stem cells; Supporting Cell; Sweat Glands; Testing; Therapeutic Uses; Tissues; Transcriptional Regulation; Transplantation; Ursidae Family; Work; burn therapy; genome-wide; improved; in vivo; in vivo regeneration; knockout gene; mouse model; novel; overexpression; programs; public health relevance; regenerative; regenerative therapy; self-renewal; skin disorder; stem cell fate; stem cell niche; tongue papilla; tool; transcription factor

DESCRIPTION (provided by applicant): Regulation of stem cell (SC) activation and self-renewal is necessary for successful tissue development and homeostasis. In many tissues this is orchestrated by signals from supporting cells within the microenvironment called the SC niche. A thorough understanding of how mammalian SC niche cells become programmed and function during development to regulate SCs is a crucial requirement for future tissue-specific regenerative therapies. While much knowledge has been gained from studies in invertebrates, a molecular understanding of how niche cells in mammalian SC niches, such as the bone marrow, brain, intestine and hair follicles, acquire their specialized status is unknown due to the complexity of the tissues and the lack of methods to isolate and characterize the cells. We have recently developed novel genetic tools to study dermal papilla (DP) cells in the hair follicle SC niche, which are thought to direct follicular SC fate. We have purified these cells, defined their molecular identity and established assays to study their fate specification. This establishes a much needed mammalian model where formation and function of the SC niche can be studied. Our long- term goal is to understand the molecular mechanisms that govern SC niche fate specification, using hair follicle morphogenesis and regeneration as a model system. Our work has identified the molecular signature of DP cells, including a battery of signaling and transcription factors (TFs). In this proposal, we will test the hypothesis that the DP signature TFs contains the activity necessary and sufficient to regulate the SC activating, hair inducing DP niche fate. We will systematically manipulate signature TF expression in DP cells in vitro and in vivo to define the transcriptional control mechanisms that specify the molecular identity and functional activity of DP niche cells. We will further establish a novel inducible DP-specific in vivo gene targeting mouse model that is currently missing in the field. Finally, we will test with available mice that are targeted for conditional gene ablation, the necessity of candidate DP signature TFs for DP niche fate specification, using this novel in vivo gene ablation model, and in parallel with our established in vitro/in vivo hybrid knockout assay. Our work will identify the core transcriptional regulation of the SC niche fate of hair follicle DP cells. Activating the transcriptional program in isolated DP cells and in regular fibroblasts bears the promise to expand fully functional cells for therapeutic use in skin reconstructive efforts. These findings will have global relevance for other regenerative tissues, where SC niches operate to maintain tissue homeostasis, and potentially will lead to development of 3D-tissue regenerative therapies. PUBLIC HEALTH RELEVANCE: A thorough understanding of the regulation of stem cell (SC) activation and self-renewal by supporting niche cells is a crucial requirement for future tissue-specific regenerative therapies. How the niche cells in mammalian SC niches acquire their specialized status is largely unknown. We will define the transcriptional control of niche fate specification of dermal papilla cells in the hair follicle SC niche, establishing a much needed mammalian model, where formation and function of the SC niche can be studied. Our work will improve our ability to create a more normal behaving skin tissue for future therapies and will also have global relevance for other regenerative tissues, where SC niches operate to maintain tissue homeostasis.

描述（由申请人提供）：干细胞（SC）活化和自我更新的调节对于成功的组织发育和体内平衡是必要的。在许多组织中，这是由来自称为SC小生境的微环境内的支持细胞的信号协调的。深入了解哺乳动物SC小生境细胞在发育过程中如何编程和发挥作用以调节SC是未来组织特异性再生疗法的关键要求。虽然已经从无脊椎动物的研究中获得了很多知识，但由于组织的复杂性以及缺乏分离和表征细胞的方法，因此对哺乳动物SC龛中的龛细胞（如骨髓，脑，肠和毛囊）如何获得其专门状态的分子理解是未知的。我们最近开发了新的遗传工具来研究毛囊SC龛中的毛乳头（DP）细胞，这些细胞被认为是指导毛囊SC命运的细胞。我们已经纯化了这些细胞，确定了它们的分子身份，并建立了检测方法来研究它们的命运规范。这建立了一个急需的哺乳动物模型，在那里可以研究SC生态位的形成和功能。我们的长期目标是以毛囊形态发生和再生为模型系统，了解支配SC生态位命运特化的分子机制。我们的工作已经确定了DP细胞的分子特征，包括一组信号和转录因子（TF）。在该提议中，我们将检验DP特征TF含有调节SC活化、毛发诱导DP生态位命运所必需和足够的活性的假设。我们将在体外和体内系统地操纵DP细胞中TF的表达，以确定指定DP小生境细胞的分子身份和功能活性的转录控制机制。我们将进一步建立一种新的诱导型DP特异性体内基因靶向小鼠模型，这是目前该领域缺乏的。最后，我们将使用这种新的体内基因消融模型，并与我们建立的体外/体内杂合敲除测定平行，用靶向条件性基因消融的可用小鼠测试候选DP特征TF用于DP小生境命运规范的必要性。我们的工作将确定毛囊DP细胞SC生态位命运的核心转录调控。激活分离的DP细胞和常规成纤维细胞中的转录程序有望扩增用于皮肤重建工作中的治疗用途的全功能细胞。这些发现将对其他再生组织具有全球相关性，其中SC壁龛用于维持组织稳态，并可能导致3D组织再生疗法的发展。 公共卫生关系：通过支持小生境细胞对干细胞（SC）激活和自我更新的调节的透彻理解是未来组织特异性再生疗法的关键要求。哺乳动物SC龛中的龛细胞如何获得其特化状态在很大程度上是未知的。我们将定义毛囊SC龛中毛乳头细胞的龛命运规范的转录控制，建立一个急需的哺乳动物模型，在那里可以研究SC龛的形成和功能。我们的工作将提高我们为未来治疗创造更正常行为皮肤组织的能力，并且还将对其他再生组织具有全球意义，其中SC壁龛用于维持组织稳态。