Regulation of embryonic patterning and adult stem cells of oral appendages

口腔附属器胚胎模式和成体干细胞的调节

• 批准号: 9304788
• 负责人: Sarah E. Millar
• 金额: $ 40万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9304788
• 关键词: Adolescent; Adult; Affect; Antineoplastic Agents; Basal Cell; Cell Fate Control; Cell Proliferation; Cell physiology; Cells; Chromatin; Data; Defect; Dental; Dental Enamel; Development; Developmental Process; Disease; Down-Regulation; Ectopic Expression; Embryo; Embryonic Development; Ensure; Enterobacteria phage P1 Cre recombinase; Epithelial; Epithelial Cells; Epithelium; Event; Excision; Exhibits; Family; Filiform Papilla; Fungiform Papilla; Gene Expression; Gene Targeting; Genetic; Genetic study; Goals; Human; Image; Imagery; Knockout Mice; Life; Ligands; Maps; Membrane; Molecular; Morphogenesis; Movement; Mus; Mutation; Natural regeneration; Odontogenesis; Oral; Oral cavity; Organ; Pathway interactions; Patients; Pattern; Phenotype; Play; Population; Positioning Attribute; Radiation therapy; Regulation; Reporter; Reporter Genes; Role; SHH gene; Signal Pathway; Signal Transduction; Site; Stem cells; Structure; Tamoxifen; Taste Buds; Taste Disorders; Taste Perception; Testing; Tissues; Tomatoes; Tongue; Tooth structure; Transgenes; Transgenic Organisms; WNT Signaling Pathway; WNT10A gene; adult stem cell; appendage; base; beta catenin; cell motility; design; experimental study; inhibitor/antagonist; malignant mouth neoplasm; member; migration; postnatal; progenitor; public health relevance; regenerative; self-renewal; small molecule; stem cell population; tongue papilla

DESCRIPTION (provided by applicant): Understanding the molecular and cellular mechanisms regulating the development, patterning and postnatal renewal of oral ectodermal appendages such as teeth, taste papillae and filiform papillae, and identifying stem and progenitor cell populations in these organs, is critical for developing regenerative strategies to replace missing teeth in cases of congenital absence or loss through disease; for understanding and treating disorders of taste, including those resulting from radiation therapy and small molecule anti-cancer drugs; and for delineating proliferation controls that may be dysregulated in oral cancers. The Wnt/ß-catenin signaling pathway is necessary for many developmental processes and plays critical roles in the proliferation and self- renewal of adult stem cell populations. Genetic studies in mice reveal key functions for Wnt/ß-catenin signaling at early stages of tooth and taste papilla morphogenesis. Signaling is activated broadly prior to the initiation of tooth and taste papilla development and gradually becomes restricted to sites of tooth and taste precursor development, ensuring correct positioning of tooth and taste organs. Based on our preliminary data, we hypothesize that proper localization of Wnt signaling requires competing activities of Wnt ligands and secreted Wnt inhibitors, and that these direct organ formation by spatially controlling the fates, movements and proliferation of oral epithelial cells. We will use live imaging of embryonic oral explants from mice that express chromatin-localized GFP specifically in Wnt-activated cells or in all basal epithelial cells, together with ubiquitous expression of membrane Tomato, to ask whether genetic deletion of Wnt inhibitors, or loss of a Wnt ligand important for tooth development, cause altered cell movements and/or patterns of proliferation. Filiform and taste papillae of the tongue are continuously renewed in adult life, an a subset of human patients with mutations in WNT10A presents with adolescent onset of oral ectodermal defects including "smooth tongues". We hypothesize that WNT10A/ß -catenin signaling controls proliferation and/or survival of adult stem and progenitor cells required for renewal of taste and filiform papillae. To test this we will ask whether loss of Wnt10a in mice affects ß-catenin signaling and the proliferation, survival, or differentiation of tongue papilla progenitor cells and will fate map Wnt responsive cells in the adult tongue to test whether they include self- renewing progenitors. To determine whether Wnt signaling is necessary for survival of functional progenitors, we will test whether inhibition of filiform and taste papilla proliferaton upon inducible transgenic expression of the Wnt inhibitor DKK1 is reversible after removal of the inducing agent. These experiments will delineate mechanisms controlling proliferation and organ renewal in the oral cavity and will provide important information for designing regenerative strategies.

描述（应用程序提供）：了解调节口腔外皮外围的发育，模式和产后更新的分子和细胞机制，例如牙齿，味道乳头和丝状乳头状，并确定这些器官中的茎和祖细胞种群，对于替代了通过疾病而造成的牙齿造成的牙齿疾病至关重要。为了理解和治疗味道障碍，包括放射疗法和小分子抗癌药物所产生的疾病；并用于描述口服癌症可能失调的增生控制。 Wnt/ß-catenin信号通路对于许多发育过程是必要的，并且在成年干细胞种群的增殖和自我更新中起着关键作用。小鼠的遗传研究揭示了在牙齿和味道乳头形态发生的早期阶段Wnt/ß-catenin信号传导的关键功能。信号传导在开始牙齿和口味乳头发育之前广泛激活，并逐渐仅限于牙齿和味道前体的发育部位，从而确保正确定位牙齿和味觉器官。根据我们的初步数据，我们假设Wnt信号的适当定位需要Wnt配体和分泌的Wnt抑制剂的竞争活动，并且这些直接器官形成是通过空间控制口服上皮细胞的命运，运动和增殖的。 我们将使用来自小鼠的胚胎口腔外植体的实时成像，这些成像表达了在WNT激活的细胞或所有基本的上皮细胞中专门表达染色质的GFP，以及膜番茄的普遍表达，以询问Wnt抑制剂的遗传缺失是Wnt抑制剂的遗传缺失，或者是对Wnt的生长量的损失，或者对牙齿的生长造成的损失，使牙齿发育不断变化。舌头的丝状和味道乳头在成人生活中不断更新，这是一部分在Wnt10a中突变的人类患者，其中包括青春期的口腔外皮缺陷，包括“光滑的舌头”。我们假设WNT10A/ß -catenin信号传导控制了更新味道和丝状乳头状所需的成年茎和祖细胞的增殖和/或存活。为了测试这一点，我们将询问小鼠中Wnt10a的损失是否影响β-catenin信号传导以及舌乳头细胞的增殖，存活或分化，并将命运成人舌头中的Wnt Wnt响应性细胞，以测试它们是否包括自我更新祖细胞。为了确定Wnt信号对于功能性祖细胞的存活是否必要，我们将测试在去除诱导剂后，抑制丝状和味道乳头乳头增生剂在Wnt抑制剂DKK1的诱导转基因表达中是否可逆。这些实验将描述控制口腔中扩散和器官更新的机制，并将为设计再生策略提供重要信息。