Post-Transcriptional Regulators of Epidermal Homeostasis and Neoplasia

项目摘要/摘要 背景：调节表皮动态平衡的转录机制有 已经确立，但最近我们发现转录后 机制在维持表皮自我更新方面起着重要作用。我们有 研究表明，RNA解旋酶DDX6是维持表皮自我更新所必需的 通过信使核糖核酸的降解和翻译途径。通过关联特定的 翻译途径的成员DDX6结合并中介翻译 自我更新和增殖转录以维持自我更新。DDX6还 与信使核糖核酸降解蛋白结合诱导分化 转录促进它们的降解，以防止过早分化。 目标/假设：本提案旨在了解 表皮动态平衡与转录后机制的肿瘤启动。 我们之前发现了与DDX6相关的蛋白质，我们的目标是 描述每种蛋白质在调节表皮生长、分化、 以及向肿瘤的进展以及作用机制。此外，我们 寻求确定DDX6及其相关复合体的特定转录本 在动态平衡和肿瘤起始时结合。 具体目的：(1)确定DDX6相关蛋白在表皮中的作用 动态平衡与肿瘤启动；(2)鉴定和鉴定转录本 与DDX6复合体有关。 研究设计：在更具临床相关性的环境中研究表皮动态平衡， 我们创造了三维完好的人类皮肤，其中包含人类表皮细胞 (已因DDX6或其关联的 蛋白质)在人类真皮基质和基底膜的上下文中， 在免疫受损的小鼠身上再生。通过使用这个模型，我们可以执行 DDX6及其相关蛋白在再生过程中的功能丧失实验 人类皮肤表征其在表皮生长、分化和修复中的作用 进展为肿瘤。我们还将使用Clip-Seq来确定RNA DDX6复合体在从正常向肿瘤进展过程中的相关性 表皮。

Project Summary/Abstract Background: Transcriptional mechanisms that regulate epidermal homeostasis have been well established but recently we have discovered that post-transcriptional mechanisms play prominent roles in maintaining epidermal self-renewal. We have shown that the RNA helicase DDX6 is necessary to maintain epidermal self-renewal through the mRNA degradation and translation pathway. By associating with specific members of the translation pathway DDX6 binds to and mediates the translation of self- renewal and proliferation transcripts to maintain self-renewal. DDX6 also associates with mRNA degradation proteins to bind differentiation-inducing transcripts to promote their degradation to prevent premature differentiation. Objective/hypothesis: This proposal seeks to understand the regulation of epidermal homeostasis and tumor initiation through post-transcriptional mechanisms. We previously identified proteins associated with DDX6 and our objective is to characterize the role of each protein in regulating epidermal growth, differentiation, and progression to neoplasia as well as the mechanisms of action. Furthermore we seek to determine the specific transcripts that DDX6 and its associated complexes bind during homeostasis and tumor initiation. Specific Aims: (1) To determine the role of DDX6 associated proteins on epidermal homeostasis and tumor initiation and (2) to identify and characterize the transcripts associated with DDX6 complexes. Study Design: To study epidermal homeostasis in a more clinically relevant setting, we generate 3-dimensionally intact human skin, containing human epidermal cells (that have been permanently knocked down for either DDX6 or its associated proteins) in the context of human dermal stroma and basement membrane, regenerated on immune compromised mice. By using this model, we can perform loss of function experiments on DDX6 and its associated proteins in regenerated human skin to characterize their role in epidermal growth, differentiation, and progression to neoplasia. We will also use CLIP- Seq to determine the RNAs associated with DDX6 complexes during the progression from normal to neoplastic epidermis.