Unveiling the evolution of neural differentiation mechanisms in animals: a study of the structure and function of the POU-IV/Brn-3 gene regulatory network in Cnidaria.

了解神经系统如何在进化过程中出现和多样化是生物学中的一个基本问题。该研究项目将使用海葵，其祖先在6亿多年前从所有其他动物谱系中分离出来，以重建动物神经发育的深层进化历史。由此产生的知识将有助于从两个方面理解神经系统的进化：（1）它将提供对6亿年前神经系统起源至关重要的发育机制的基本见解，以及（2）它将提供有关这些机制如何在干预时间段内多样化的新信息。该项目还将通过积极参与阿肯色州INBRE（IDEA生物医学研究卓越网络）的本科生导师计划，让少数民族本科生直接参与研究，从而扩大代表性不足的少数民族在STEM中的参与。此外，该研究将通过使用独特的非传统动物模型系统来加强阿肯色州大学的研究和教育环境，使学生能够轻松获得CRISPR-Cas9基因组编辑，下一代测序和共聚焦显微镜等尖端生物技术的第一手经验。这项研究将推进有关神经系统起源和进化的基础知识，并通过基础科学研究和教育造福社会。在双侧性动物（例如小鼠、蠕虫和苍蝇）中，IV类POU同源结构域转录因子（POU-IV或Brn-3）在调节神经亚型分化和维持中发挥进化保守的作用。然而，目前尚不清楚POU-IV功能的保护是否超出了Bilateria，或者是否存在分歧，新的调节机制存在于具有神经系统的非bilateria动物群体中，如刺胞动物（例如水母，珊瑚和海葵）-Bilateria的姐妹群。为了解决这个问题，本研究将剖析刺胞动物海葵Nematostella vectensis中POU-IV基因调控网络的结构和功能。具体而言，该项目将专注于1）通过CRISPR-Cas9介导的基因组编辑将深入的基因表达分析与基因功能分析相结合，定义POU-IV指定的神经亚型，以及2）通过结合基因功能扰动，ChIP-seq，和转录组分析。该项目由神经系统集群组织计划联合资助，激励竞争研究计划（EPSCoR）该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Understanding how nervous systems emerged and diversified over evolutionary time is a fundamental problem in biology. This research project will use sea anemones, whose ancestors split off from all other animal lineages over 600 million years ago, to reconstruct the deep evolutionary history of neural development in animals. The resultant knowledge will contribute to the understanding of nervous system evolution in two ways: (1) it will provide fundamental insights into developmental mechanisms that were critical for the origin of nervous systems over 600 million years ago, and 2) it will provide new information about how these mechanisms have diversified in the intervening time period. This project will additionally broaden participation of underrepresented minorities in STEM by actively involving minority undergraduate students directly in research through participation in the Undergraduate Student Mentoring Program of Arkansas INBRE (IDeA Network of Biomedical Research Excellence). Furthermore, the research will strengthen both the research and educational environments at the University of Arkansas by using a unique, non-traditional animal model system that makes it easy give students first-hand experience with cutting-edge biological technologies such as CRISPR-Cas9 genome editing, Next Generation Sequencing, and confocal microscopy. The research will advance fundamental knowledge about the origin and evolution of nervous systems, as well as benefit society through basic science research and education. In bilaterian animals (e.g. mice, worms and flies), the class IV POU homeodomain transcription factor (POU-IV or Brn-3) plays an evolutionarily conserved role in regulating neural subtype differentiation and maintenance. However, it is unclear whether the conservation of POU-IV function extends beyond Bilateria, or whether divergent, novel regulatory mechanisms exist in non-bilaterian animal groups with nervous systems such as Cnidaria (e.g. jellyfish, corals and sea anemones) – the sister group of Bilateria. To address this problem, the research will dissect the structure and function of the POU-IV gene regulatory network in the cnidarian sea anemone Nematostella vectensis. Specifically, this project will focus on 1) defining neural subtypes specified by POU-IV by combining in-depth gene expression analyses with gene function analyses via CRISPR-Cas9-mediated genome editing, and 2) dissecting the structure of the POU-IV gene regulatory network underpinning neural fate specification by combining gene function perturbation, ChIP-seq, and transcriptome analyses.This project is jointly funded by the Organization Program of the Neural Systems Cluster, and the Established Program to Stimulate Competitive Research (EPSCoR).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.