Genetically engineered ants to label and study neurons involved in social behavior

摘要 这项提议的目标是为调节社交网络的神经回路产生基因报告系 哈氏跳蚁的行为，并利用这些线来可视化成年工人的大脑重构 对自己进行重新编程以表现得像蚂蚁后。 群居昆虫是研究大脑功能和行为表观遗传调控的新兴模式系统 因为同一个基因组在不同的种姓中指定了不同的行为状态。大脑是否以及如何 工人和女王的不同连接，以实现不同的种姓特定行为集尚不清楚。 在Harpegnathos蚂蚁中，成年工蚁可以通过戏剧性的种姓转变成为女王 生殖、生理和行为的表型变化。Harpegnathos蚂蚁的这一特征允许 基因工程的等位基因很容易繁殖，因为任何个体都可以繁殖。 成年哈佩格纳托斯工人成为女王的能力为机械师提供了独特的机会 成人大脑可塑性的解剖。单细胞rna-seq分析揭示了细胞的主要变化。 同时影响神经元和神经胶质细胞的成分，表明伴随着大脑的结构性重构 种姓转变。指导这种大脑重塑的分子信号仍不清楚。 我们之前展示了神经肽Corazin刺激狩猎，这是一种工人特有的行为，并且 随着工人成为女王，他们受到的监管会降低。自那以后，我们获得了新的初步证据，表明蚂蚁 人类加压素的同系物以种属特异性的方式表达，并可能也调节着一个亚集 在哈佩格纳索蚂蚁中的社会行为。我们假设这些神经肽发出的信号引导大脑 在种姓转变期间支持社会行为转变的重塑事件。 在目标1中，我们将利用转基因方法标记产生科拉宁和加压素的神经元和 并观察它们在自然种姓转变过程中的重塑。 在目标2中，我们将利用CRISPR/Cas9生成敲入驱动程序和报告程序线来标记神经元，这些神经元 对柯拉西林或加压素作出反应，并在细胞和突触水平显示其可塑性。 神经肽。 这些实验将揭示关于Harpegnathos蚂蚁成年大脑可塑性的关键信息，并提供 复杂的遗传工具，用于进一步剖析这些人的社会行为的表观遗传调节 蚂蚁。考虑到考拉宁和加压素在哺乳动物中的对应关系，我们的研究结果有望产生 广泛影响我们对神经肽如何调节大脑可塑性和社会行为的理解。

ABSTRACT The goal of this proposal is to generate genetic reporter lines for neuronal circuits that regulate social behavior in Harpegnathos saltator ants and to utilize these lines to visualize brain remodeling as adult workers reprogram themselves to behave as ant queens. Social insects are an emerging model system to study the epigenetic regulation of brain function and behavior because the same genome specifies alternative behavioral states in different castes. Whether and how brains of workers and queens are differently wired to implement distinct sets of caste-specific behaviors is not known. In Harpegnathos ants, adult workers can become queens via a caste transition that involves dramatic phenotypic changes in reproduction, physiology, and behavior. This feature of Harpegnathos ants allows for easy propagation of engineered alleles, as any individual can become reproductive. The ability of adult Harpegnathos workers to become queens offers unique opportunities for the mechanistic dissection of adult brain plasticity. Single-cell RNA-seq analyses revealed major changes in cellular composition affecting both neurons and glia, indicating that a structural remodeling of the brain accompanies the caste transition. The molecular signals that direct this brain remodeling remain unknown. We previously showed that the neuropeptide corazonin stimulates hunting, a worker-specific behavior, and is downregulated as workers become queens. We have since obtained new preliminary evidence that the ant homolog of human vasopressin is expressed in a caste-specific manner and likely also regulates a subset of social behaviors in Harpegnathos ants. We hypothesize that signaling by these neuropeptides directs brain remodeling events that underpin the switch in social behaviors during the caste transitions. In Aim 1, we will utilize a transgenic approach to label corazonin- and vasopressin-producing neurons and their projection with membrane-bound GFP and to observe their remodeling during the natural caste transition. In Aim 2, we will utilize CRISPR/Cas9 to generate knock-in driver and reporter lines to label neurons that respond to corazonin or vasopressin and visualize their plasticity at the cellular and synaptic level in response to the neuropeptides. These experiments will reveal crucial information on adult brain plasticity in Harpegnathos ants and provide sophisticated genetic tools for the further dissection of the epigenetic regulation of social behavior in these ants. Given that corazonin and vasopressin have mammalian counterparts, our results are expected to have a broad impact on our understanding of how neuropeptides regulate brain plasticity and social behavior.