EDGE CT: Enabling cell-specific functional genomics in a colonial animal

刺胞动物门是一组凝胶状的，主要是海洋动物，包括水母，珊瑚和海葵。大多数刺胞动物结构简单，呈放射状对称。刺胞动物重要的一个原因是它们是所有两侧对称动物的近亲，这一组包括昆虫，蠕虫和脊椎动物。正因为如此，研究刺胞动物生物特征的分子或细胞基础可以让生物学家推断这种特征在刺胞动物和两侧刺胞动物的祖先中是如何发挥作用的。反过来，这可以帮助科学家了解这种特征目前在更复杂的动物（包括人类）中的作用。在这个项目中，研究小组将开发工具来研究基因如何在一种名为Hydractinia的刺胞动物模式生物中发挥作用。水螅是一种理想的模式生物，因为它价格低廉，易于维护，并且不受伦理因素的限制。此外，Hydractinia是许多过程的模型，这些过程对研究更复杂生物的生物学家来说很有趣，包括再生，干细胞维持和移植组织的排斥。该项目的目标是让生物学家研究任何细胞类型中的任何Hydroactinia基因，在任何空间位置和动物生命中的任何时间点。该项目开发的工具将与快速传播工作相结合，包括与更广泛的科学界分享协议和材料。此外，主要研究人员和他们的团队共同致力于教育和推广活动，并计划创造性的方法来吸引人们，包括K-12学生和普通公众。技术摘要刺胞动物是形态简单的动物和bilaterians最近的亲戚。因此，它们是理解许多两侧对称特征进化起源的关键。尽管一些功能基因组学工具在一些刺胞动物的可用性，它是目前不可能控制基因表达的细胞类型或时间/空间位置的水平。这对于研究过度表达或敲低/敲除是胚胎致死的基因以及研究环境特异性基因功能尤其成问题。此外，由于刺胞动物特征的多样性，在现有的刺胞动物模式物种中研究许多刺胞动物特征，包括群体性、形态多态性、同种异体识别和干细胞多能性是困难或不可能的。本计画旨在发展共生水螅的细胞类型特异性功能基因组学。目标1的工作将集中在使用单细胞RNAseq数据生成所有成体Hydractinia细胞类型的基因表达图谱，然后识别和验证排他性细胞类型标记，并为尽可能多的细胞类型生成转基因报告动物。目标2的工作将开发一种基于重组酶的条件基因敲除系统，包括允许细胞类型特异性重组酶的菌株和Hydractinia中条件等位基因的菌株。已计划开展一系列多样化的活动，以将该项目产生的工具和技术迅速传播给更广泛的科学界。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知识价值进行评估，被认为值得支持影响审查标准。

Public Award AbstractThe phylum Cnidaria is a group of gelatinous, primarily marine animals that includes jellyfish, corals, and sea anemones. Most cnidarians are structurally simple and have radial symmetry. One reason that cnidarians are important is that they are the closest relatives of all bilaterally symmetrical animals, a group that includes insects, worms, and vertebrates. Because of this, studying the molecular or cellular basis of a biological trait in a cnidarian allows biologists to infer how that trait might have functioned in the ancestors of cnidarians and bilaterians. This, in turn, can help scientists understand how the trait currently functions in more complex animals, including humans. In this project, the research team will develop tools to study how genes function in a cnidarian model organism called Hydractinia. Hydractinia is an ideal model organism because it is inexpensive and easy to maintain, and not restricted by ethical considerations. In addition, Hydractinia is a model for many processes that are interesting to biologists studying more complex organisms, including regeneration, stem cell maintenance, and the rejection of transplanted tissues. The goal of this project is to allow biologists to study any Hydractinia gene in any cell type at any spatial location and at any timepoint during the animal's life. The tools developed in this project will be paired with rapid dissemination efforts, including the sharing of protocols and materials with the broader scientific community. In addition, the principal investigators and their teams share a strong commitment to education and outreach activities, and have planned creative methods to engage people, including K-12 students and the general public.Technical AbstractCnidarians are morphologically simple animals and the closest relatives of bilaterians. As such, they are key to understanding the evolutionary origin of many bilaterian features. Despite the availability of some functional genomics tools in a few cnidarians, it is not currently possible to control gene expression at the level of cell type or temporal/spatial location. This is particularly problematic for the study of genes for which overexpression or knockdown/knockout is embryonic lethal, and for studying context-specific gene function. Moreover, due to the diversity of cnidarian characters, it is either difficult or impossible to study many cnidarian traits, including coloniality, morphological polymorphism, allorecognition, and stem cell pluripotency in existing cnidarian model species that lack these features. This project aims to develop cell type-specific functional genomics in the hydrozoan Hydractinia symbiolongicarpus. Work in Aim 1 will focus on generating an atlas of gene expression for all adult Hydractinia cell types, using single-cell RNAseq data, followed by identifying and validating exclusive cell type markers and generating transgenic reporter animals for as many cell types as possible. Work in Aim 2 will develop a recombinase-based conditional gene knockout system including strains that permit cell type-specific recombinases and strains for conditional alleles in Hydractinia. A diverse set of activities have been planned to rapidly disseminate the tools and techniques resulting from this project to the broader scientific community.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.