Characterization of the roles and regulation of Draxin in cranial neural crest

Draxin 在颅神经嵴中的作用和调节的表征

• 批准号: 10400365
• 负责人: Erica Hutchins
• 金额: $ 8.56万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10400365
• 关键词: 3' Untranslated Regions; Affect; Award; COVID-19; Cartilage; Cephalic; Cleft Palate; Craniofacial Abnormalities; Defect; Development; DiGeorge Syndrome; Disease; Down-Regulation; Embryo; Epithelial; Equilibrium; Face; Faculty; Fluorescence Resonance Energy Transfer; Funding; Genetic Transcription; Goals; Head; Knowledge; Lead; Mandibulofacial Dysostosis; Mediating; Mesenchymal; Microscopy; Molecular; Mutation; Names; Neural Crest; Neural Crest Cell; Neural tube; Neuraxis; Parents; Phase; Population; Positioning Attribute; Proteins; Publications; Publishing; RNA immunoprecipitation sequencing; RNA-Binding Proteins; Regulation; Research; Role; Secure; Signal Transduction; Skeleton; Techniques; Time; Translational Research; Universities; WNT Signaling Pathway; Work; career; craniofacial; craniofacial structure; epithelial to mesenchymal transition; experimental study; in vivo; malformation; migration; molecular imaging; neuroepithelium; post-doctoral training; programs; public health relevance; single molecule; skills; spatiotemporal; stem cell population; tenure track

PROJECT SUMMARY/ABSTRACT The neural crest (NC) is a stem cell population that originates within the forming central nervous system. NC cells delaminate from the neuroepithelium by undergoing a spatiotemporally regulated epithelial— mesenchymal transition (EMT) to exit from the neural tube. Cranial NC cells, which arise in the head region of the embryo and are the only NC population in vivo with the ability to differentiate into craniofacial skeleton and cartilage, are indispensable for the development of the face; mutations affecting NC development result in numerous diseases and malformations affecting the craniofacial structures. The focus of my postdoctoral work has been to study the mechanisms that control and facilitate cranial NC EMT. During the first phase of my postdoctoral training, I have shown that this developmental EMT program is controlled by temporally restricted expression of the Wnt antagonist, Draxin. A hallmark of Draxin's function during EMT is its transient expression and rapid downregulation; perdurance of Draxin has deleterious effects on cranial NC EMT through dysregulation of downstream targets of canonical Wnt signaling. Through the support of the K99, I discovered that the transience of Draxin expression in cranial NC is mediated post-transcriptionally via its 3'-untranslated region (UTR). Importantly, Draxin is stabilized by the RNA-binding protein Elavl1/HuR at the premigratory stage, then targeted to cytoplasmic processing bodies (P-bodies) for decay to drive proper cranial NC EMT. Collectively, these discoveries begin to unravel a new mechanism whereby cranial NC EMT is regulated through post-transcriptional regulatory mechanisms balancing stability and decay of a molecular rheostat, Draxin. COVID-19 research restrictions and university closures severely delayed my career plans and development. Through the support of the K99, I completed many of the goals proposed in Aims 1 and 3 of my original proposal, which sought to illuminate the interaction between Draxin and Wnt signaling, and the regulation Draxin expression, respectively. However, COVID-19 research restrictions severely delayed the completion of Aim 1 and progress of Aim 2, which sought to apply time-lapse and advanced microscopy techniques (e.g. FRET) to more fully explore Draxin function. Further, completion of Aim 3 and publication of these studies requires additional experiments in single-molecule imaging and RIP-seq. A funding extension would allow me to develop critical new skills in advanced microscopy and RIP-seq to gain a mechanistic understanding of Draxin activity during cranial NC EMT, and allow me to comple the revision experiments necessary to publish the work performed under the parent K99 award to help me secure a tenure-track faculty position, establish a vibrant independent research program in the developmental signaling field, and better equip me with the knowledge necessary to transition into the study of cranial NC development and migration.

项目总结/摘要 神经嵴（NC）是起源于形成中枢神经系统的干细胞群。 系统NC细胞通过经历时空调节的上皮细胞-神经细胞- 间充质转化（EMT）以从神经管退出。颅NC细胞，出现在头部区域， 胚胎和是唯一的NC群体在体内具有分化成颅面骨骼的能力， 软骨是面部发育不可缺少的;影响NC发育的突变导致 影响颅面结构的许多疾病和畸形。我博士后工作的重点 一直在研究控制和促进颅NC EMT的机制。在我的第一阶段 博士后培训，我已经表明，这种发展EMT计划是由时间限制控制， Wnt拮抗剂Draxin的表达。Draxin在EMT期间的功能的标志是其瞬时表达 和快速下调; Draxin的持久性通过以下途径对颅NC EMT产生有害影响： 典型Wnt信号传导的下游靶标的失调。通过K99的支持，我发现 Draxin在颅侧NC中表达的瞬时性是通过其3 '-非翻译区在转录后介导的， 区域（UTR）。重要的是，Draxin在迁移前由RNA结合蛋白Elavl 1/HuR稳定。 阶段，然后靶向细胞质加工体（P体）进行衰变，以驱动适当的颅NC EMT。 总的来说，这些发现开始解开一个新的机制，即颅NC EMT是受管制的 通过转录后调节机制平衡分子变阻器的稳定性和衰减， 德拉辛COVID-19研究限制和大学关闭严重推迟了我的职业计划， 发展通过K99的支持，我完成了我的目标1和3中提出的许多目标。 最初的提议，试图阐明Draxin和Wnt信号之间的相互作用， 调节Draxin表达。然而，COVID-19研究限制严重推迟了 目标1完成，目标2取得进展，旨在应用延时和先进显微镜 技术（例如FRET），以更充分地探索Draxin功能。此外，目标3的完成和 这些研究需要在单分子成像和RIP-seq中进行额外的实验。资金延期 这将使我能够在先进的显微镜和RIP-seq中发展关键的新技能，以获得一种机械的 了解Draxin在颅NC EMT期间的活动，并允许我完成修订实验 有必要发表在父母K99奖下完成的工作，以帮助我获得终身教职 立场，建立一个充满活力的独立研究计划，在发展信号领域，更好地 使我具备必要的知识，过渡到颅NC发展和迁移的研究。