Local Role for Steroids in Regenerative Growth in Drosophila

类固醇在果蝇再生生长中的局部作用

• 批准号: 9911636
• 负责人: Douglas Emmons Terry
• 金额: $ 4.55万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9911636
• 关键词: Adult; Alleles; Anabolism; Androgens; Animals; Apoptotic; Back; Binding; Biological Models; Biology; Cells; Characteristics; Complex; Crustacea; Data; Development; Drosophila genus; Drosophila melanogaster; Ecdysone; Ecdysterone; Epithelial; Epithelium; Estrogens; Gene Expression; Gene Proteins; Genes; Genetic Transcription; Goals; Growth; Homologous Gene; Hormones; Human; Immunofluorescence Immunologic; Impairment; In Situ Hybridization; Injury; Laboratories; Ligand Binding Domain; Ligands; Light; Link; Malignant Neoplasms; Malignant neoplasm of prostate; Measures; Methods; Modeling; Molecular; NCOA3 gene; Natural regeneration; Nuclear Hormone Receptors; Oncoproteins; Orthologous Gene; Output; Pathologic; Pathway interactions; Pattern; Peripheral; Physiologic pulse; Porifera; Production; Proliferating; Proteins; Publishing; RNA; RNA Interference; Receptor Activation; Receptor Signaling; Reporter; Role; Signal Pathway; Signal Transduction; Site; Skin wound healing; Stanolone; Stem Cell Development; Stem Cell Factor; Steroid Receptors; Steroids; Surgical wound; System; Temperature; Testing; Therapeutic; Tissues; Transcription Coactivator; Transgenes; Tumor Suppressor Genes; Wing; Work; blastema; clinically significant; coactivator-associated arginine methyltransferase 1; cofactor; disc regeneration; ecdysone receptor; epithelial stem cell; epithelial wound; epithelium regeneration; experimental study; fly; genetic manipulation; germline stem cells; hormonal signals; insight; limb regeneration; malignant breast neoplasm; nano; notch protein; programs; promoter; receptor binding; recruit; regenerative; stem; steroid hormone; success; tissue regeneration; tissue repair; tumor; wound; wound healing

PROJECT SUMMARY The fruit fly, Drosophila melanogaster, is a well-established model system to define conserved mechanisms that control proliferation, survival, invasiveness, and stem-like qualities of developing epithelia. A number of clinically significant oncogenes and tumor suppressors have been discovered and defined in flies (e.g. Yki/Yap1, Notch and archipelago/Fbw7), and multiple Drosophila tumor models are currently being used as discovery platforms to identify potential therapeutic compounds and cocktails. The Drosophila Taiman (Tai) and Yorkie (Yki) transcriptional co-activator proteins are the sole fly orthologs of the well-established human oncoproteins SRC-3 and Yap1. Tai is the prime coactivator for the ecdysone receptor (EcR), a functional homolog of nuclear hormone receptors, that controls many aspects of epithelial and stem cell development. Yki is the main transcriptional effector of the Hippo pathway. Our laboratory discovered that Yki and Tai physically associate on target gene promoters and that this Tai-Yki complex enables crosstalk between the Hippo and steroid hormone pathways during developmental and pathologic growth in Drosophila. The current project is focused on a role for the Tai-Yki axis in homeostatic regrowth of wing epithelium following wounding, and thus lies at the intersection of wound healing and cancer noted by Harold Dvorak’s prescient description of cancer as “wounds that do not heal”. I have found preliminary evidence that transient and local reduction in the ability of cells surrounding epithelial wounds to synthesize 20-hydroxyecdysone (20HE), the steroid ligand of EcR, inhibits wound repair and regeneration. In parallel, I have found that EcR transcriptional activity is also significantly induced within cells surrounding the wound. These data, in light of the Tai-Yki complex, could link 20HE/EcR steroid signaling to Yki/Yap1-driven growth at the site of the wound. Indeed, Tai supports expression of certain Yki pro-growth targets in uninjured discs that are upregulated during regeneration (e.g. dIlp8). Thus, I will test the hypothesis that the steroid hormone 20HE is required for imaginal wing disc regeneration through promoting transcriptional activity of Tai-dependent Yki targets. The Specific Aims of this project are: 1) test the requirement for 20HE biosynthesis in wing disc regeneration; 2) define the pattern of EcR activity in regenerating wing discs; 3) test the local requirement for the Tai-Yki axis in regenerative growth. In Aim 1, I will compare the extent of regeneration of wing discs depleted of 20HE biosynthesis genes to control discs, and determine the pattern of 20HE biosynthesis gene expression in regenerating imaginal wing discs. In Aim 2, I will place EcR activation into the context with other pathways activated during regeneration. In Aim 3, I will determine the effect of disrupting Tai-Yki association on the extent of regeneration and Tai-dependent Yki target expression in wing discs. Success in these studies will provide insight into how local hormone synthesis regulates homeostatic wound repair and, potentially, pathologic cancer growth.

项目摘要 果蝇（Drosophila melanogaster）是定义保守机制的成熟模型系统 其控制发育中上皮细胞的增殖、存活、侵袭性和干细胞样性质。一些 临床上重要的致癌基因和肿瘤抑制基因已经在果蝇中发现和确定（例如， Yki/Yap 1、Notch和archipelago/Fbw 7），以及多种果蝇肿瘤模型目前被用作 发现平台，以确定潜在的治疗化合物和鸡尾酒。Drosophila Taiman（Tai） 和Yorkie（Yki）转录共激活蛋白是唯一的果蝇直系同源物， 癌蛋白SRC-3和Yap 1。Tai是蜕皮激素受体（EcR）的主要共激活剂， 核激素受体的同系物，控制上皮细胞和干细胞发育的许多方面。 Yki是Hippo途径的主要转录效应子。我们的实验室发现伊琪和泰 在靶基因启动子上物理缔合，并且这种Tai-Yki复合物能够在靶基因启动子之间产生串扰。 果蝇发育和病理生长过程中的海马和类固醇激素途径。 当前项目的重点是太极轴在翅膀上皮稳态再生长中的作用 受伤后，因此在伤口愈合和癌症的交叉点上，哈罗德·德沃夏克指出， 将癌症描述为“无法愈合的伤口”。我发现了初步证据 以及上皮伤口周围细胞合成20-羟基蜕皮激素的能力的局部降低 （20 HE）是EcR的类固醇配体，抑制创伤修复和再生。与此同时，我发现， 在伤口周围的细胞内也显著诱导转录活性。这些数据，根据 Tai-Yki复合物可以将20 HE/EcR类固醇信号传导与伤口部位Yki/Yap 1驱动的生长联系起来。 事实上，Tai支持在未受伤的椎间盘中表达某些Yki促生长靶点，这些靶点在治疗过程中上调。 再生（例如dIlp 8）。因此，我将测试类固醇激素20 HE是必需的假设， 通过促进Tai依赖性Yki靶的转录活性来再生成虫翅盘。的 本项目的具体目的是：1）测试翅盘再生过程中20 HE生物合成的需求; 2） 确定再生翅盘中EcR活性的模式; 3）测试当地对Tai-Yki轴的需求， 再生生长在目标1中，我将比较20 HE耗尽的翅盘再生的程度 20 HE生物合成基因控制光盘，并确定20 HE生物合成基因表达的模式， 再生成虫翅盘。在目标2中，我将把EcR激活与其他途径放在一起 在再生过程中激活。在目标3中，我将确定破坏Tai-Yki协会对 再生的程度和Tai依赖的Yki靶在翅盘中的表达。这些研究的成功将 提供了对局部激素合成如何调节稳态伤口修复的深入了解，并且可能， 病理性癌症生长。