CAREER: Functional Analysis of microRNAs in Early Development

为了了解新受精的卵子是如何成为多细胞有机体的，关键是要研究早期胚胎内的细胞如何整合各种信号来驱动发育。这项研究的重点是了解细胞如何在穿过胚胎时采用特定的细胞命运。早期胚胎中的细胞启动特定的基因，部分是对它们从邻近细胞收到的化学信号的反应。这个项目将发现基因是如何由一组调控的RNA控制的。这些调控RNA控制着几种细胞类型中许多基因的表达水平，以确保正常的发育。因此，这项工作有助于从根本上理解动物的发育。该项目包括与拟议研究项目协同的教育活动。第一个教育活动涉及特拉华州儿童博物馆的一个外展项目，在那里，少年派和她的学生开发了一种移动显微镜，供幼儿进行动手探索活动。第二项教育活动是通过灌输对科学教学的信心和支持科学课程发展来增强未来幼儿教师的知识基础。廉价的智能手机显微镜平台被放在实习教师手中，以培养未来在他们自己的教室里使用。该项目被纳入本科生和研究生的研究培训以及在特拉华大学教授的课程。拟议的教育活动结合了PI在发展生物学、显微镜和正在进行的研究合作方面的专业知识。MicroRNAs(MiRNAs)是高度保守的调节RNA分子，控制着无数的生物过程，包括发育。在发育的早期，细胞的规格和模式的形成是由基因调控网络(GRN)和信号通路的交叉调节控制的。信号的形态原梯度是关键的调节，需要严格控制，以确保胚胎的精确组织。这个项目解决了miRNAs执行这一关键调控功能的首要假设。它的目标是了解miRNAs如何整合GRN和信号通路来推动发育。为了实现这一目标，这项研究使用海胆来研究广泛生物共有的复杂发育过程。海胆的GRN研究非常充分，它的大多数miRNA家族都由一个物种组成，这使得它易于进行独特的、强大的功能分析。为了确定miRNAs在胚胎发育早期控制细胞命运和指导细胞运动的机制，PI将确定骨骼发育的初级间充质细胞(PMC)谱系中高度保守的microRNA miR-31的调控机制。本项目研究miR-31如何协调抑制PMC GRN成分并交叉调节信号通路以驱动PMC发育，使用蛋白质组学、转录学、成像、胚胎移植和分子方法。总体而言，这项研究将推动miRNA研究领域的发展，并有助于从根本上理解早期发育过程。

To understand how a newly fertilized egg becomes a multicellular organism, it is critical to examine how cells within the early embryo integrate various signals to drive development. This research focuses on understanding how cells adopt a specific cell fate as they traverse through the embryo. The cells within the early embryo turn on specific genes, in part, in response to chemical cues they receive from their neighboring cells. This project will discover how genes are controlled by a group of regulatory RNAs. These regulatory RNAs control the level of gene expressions of many genes in several cell types to ensure proper development. Thus, this work contributes to the fundamental understanding of animal development. The project includes education activities that are synergistic to the proposed research project. The first educational activity involves an outreach program at the Delaware Children's Museum where the PI and her students develop a mobile microscope for young children to conduct hands-on, exploratory activities. The second educational activity is to enhance the knowledge base of future early childhood teachers by instilling confidence in science teaching, and by supporting science curriculum development. Inexpensive smartphone microscope platforms are placed in the hands of student teachers to foster future use in their own classrooms. This project is integrated into research training of undergraduate and graduate students and courses taught at the University of Delaware. The proposed educational activities incorporate the PI's expertise in development biology, microscopy, and ongoing research collaborations. MicroRNAs (miRNAs) are highly conserved regulatory RNA molecules that control a myriad of biological processes, including development. In early development, cell specification and pattern formation are controlled by cross-regulation of gene regulatory networks (GRN) and signaling pathways. Signaling morphogen gradients are critical regulators that need to be tightly controlled in order to ensure that the precise organization of the embryo is achieved. This project addresses the overarching hypothesis that miRNAs perform this critical regulatory function. Its goal is to understand how miRNAs integrate GRNs and signaling pathways to drive development. To accomplish this goal, this study uses the sea urchin to study complex developmental processes that are shared by a wide range of organisms. The sea urchin has an exceptionally well-studied GRN and most of its miRNA families consist of a single species, which makes it amenable to unique, powerful functional analysis. To determine the mechanisms by which miRNAs control cell fate specification and directed cell movement during early embryogenesis, the PI will determine regulatory mechanisms of a highly conserved microRNA, miR-31, in the skeletogenic primary mesenchyme cell (PMC) lineage. This project examines how miR-31 coordinately suppresses PMC GRN components and cross-regulates signaling pathways to drive PMC development, using proteomic, transcriptomic, imaging, embryo transplantation, and molecular approaches. Overall, this study will advance the field of miRNA research and contribute to the fundamental understanding of early developmental processes.